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International Journal of Biological Sciences



International Journal of Biological Sciences RSS feed -- Volume 13



Published: Tue, 12 Sep 2017 04:00:00 GMT

Last Build Date: Tue, 12 Sep 2017 04:00:00 GMT

 



Identification and Analysis of P53-Mediated Competing Endogenous RNA Network in Human Hepatocellular Carcinoma

2017

Recent studies have indicated that long non-coding RNAs (lncRNAs) and mRNA function as competing endogenous RNAs (ceRNAs) that compete to bind to shared microRNA (miRNA) recognition elements (MREs) to perform specific biological functions during tumorigenesis. The tumor suppressor p53 is a master regulator of cancer-related biological processes by acting as a transcription factor to regulate target genes including miRNA and lncRNA. However, the mechanism in human hepatocellular carcinoma and whether p53-mediated RNA targets could form ceRNA network remain unclear. Here, we identified a series of differential expressed miRNAs, lncRNA and mRNA which were potentially regulated by p53 using RNA sequencing in HepG2. Genomic characteristics comparative analysis showed significant differences between mRNAs and lncRNAs. By integrating experimentally confirmed Ago2 and p53 binding sites, we constructed a highly reliable p53-mediated ceRNA network using hypergeometric test. The KEGG pathway enrichment analysis showed that the ceRNA network highly enriched in the cancer or p53-associated signaling pathways. Finally, using betweenness centrality analysis, we identified five master miRNAs (hsa-miR-3620-5p, hsa-miR-3613-3p, hsa-miR-6881-3p, hsa-miR-6087 and hsa-miR-18a-3p) that regulated most of the target RNAs, suggesting these miRNAs play central roles in the whole p53-mediated ceRNAs network. Taken together, our results provide a new regulatory mechanism of p53 networks for future studies in cancer therapeutics.




ATP2B1 gene Silencing Increases Insulin Sensitivity through Facilitating Akt Activation via the Ca2+/calmodulin Signaling Pathway and Ca2+-associated eNOS Activation in Endothelial Cells

2017

Endothelial cell insulin resistance may be partially responsible for the higher risk of atherosclerosis and cardiovascular disease in populations with insulin resistance and type 2 diabetes mellitus (T2DM). A genome-wide association study revealed a significant association between the ATPase plasma membrane Ca2+ transporting 1 (ATP2B1) gene and T2DM in two community-based cohorts from the Korea Association Resource Project. However, little is known about the implication of the ATP2B1 gene on T2DM. In the present study, we investigated the role of the ATP2B1 gene in endothelial cell insulin sensitivity. ATP2B1 gene silencing resulted in enhanced intracellular calcium concentrations and increased insulin-induced Akt activation compared to that in the negative siRNA-transfected HUVECs (Human Umbilical Vein Endothelial Cells). The elevated insulin sensitivity mediated by ATP2B1 gene silencing was Ca2+/calmodulin-dependent, as verified by administration of the calcium chelator BAPTA-AM or the calmodulin-specific antagonist W7. Moreover, higher levels of phosphorylation of eNOS (Ser1177) were observed in ATP2B1-silenced HUVECs. In addition to BAPTA-AM and W7, L-NAME, an eNOS antagonist, abolished insulin-induced Akt phosphorylation at Ser473 in both si-Neg and si-ATP2B1-transfected endothelial cells. These results indicate that the enhanced insulin sensitivity in ATP2B1-silenced endothelial cells is alternatively dependent on an increase in intracellular Ca2+ and the subsequent activation of the Ca2+/calmodulin/eNOS/Akt signaling pathway. In summary, ATP2B1 gene silencing increased insulin sensitivity in endothelial cells by directly modulating the Ca2+/calmodulin signaling pathway and via the Ca2+/calmodulin/eNOS/Akt signaling pathway alternatively.




Chronic Osteomyelitis Increases the Incidence of Type 2 Diabetes in Humans and Mice

2017

Background: To compare the risk of type 2 diabetes (T2DM) between patients with and without chronic osteomyelitis (COM), both in humans and in mice, and to explore risk factors in COM patients who developed T2DM.

Methods: One hundred seven patients with COM and 114 patients without COM were consecutively enrolled and retrospectively analysed. Clinical data concerning the time to develop diabetes, glucose metabolism, lipid metabolism, inflammatory factors, mental health and frequency of specialist visits were collected. A mouse model of osteomyelitis was used to verify the presence of impaired glucose metabolism and depression. All data were processed by SPSS.

Results: The incidence of T2DM was 2.37-fold higher in patients with COM than in those without. In COM patients, subjects with T2DM (DDM) had higher BMI, less exercise and more frequent visits to specialists than those without (Con). Glucose and lipid metabolism were worse in patients with DDM. Patients with DDM had higher levels of white blood cells (12.9±2.1×109/L vs. 11.7±2.2×109/L, p=0.027), CRP (28.4±4.5 mg/L vs. 22.0±4.8 mg/L, p<0.001), TNF-α (13.5±5.0 pg/mL vs. 9.4±2.6 pg/mL, p= 0.003) and IL-6 (12.9±3.2 pg/mL vs. 9.2±2.7 pg/mL, p<0.001). Significantly increased fasting blood glucose concentrations and impairment of oral glucose tolerance tests were also observed in mice modelling osteomyelitis, which were accompanied by elevated TNF-α and IL-6 levels. Furthermore, the proportion of depression (63.2% vs. 35.2%, p=0.003) and severe anxiety (31.6% vs. 9.1%, p=0.002) were significantly higher in the DDM group. Osteomyelitis mice showed obvious depressive-like behaviours. The levels of TNF-α, IL-6, CRP, BMI, and LDL; lack of exercise; SAS; HAQ; and SF36 assessment were risk factors for the development of T2DM in COM patients.

Conclusions: Chronic osteomyelitis increased the incidence of T2DM in both humans and mice. Inflammation, mental illness and lack of exercise were risk factors for the occurrence of T2DM in osteomyelitis. Comprehensive consideration of patient history, including metabolism and mental health, is needed in planning future treatment.




Antisense lncRNA FOXF1-AS1 Promotes Migration and Invasion of Osteosarcoma Cells Through the FOXF1/MMP-2/-9 Pathway

2017

Osteosarcoma (OS) is the most common primary malignant bone cancer in children and adolescents. Long non-coding RNAs (lncRNAs) have been shown to play significant role in various cancers, including OS. In a previous study, we have reported that a novel antisense lncRNA FOXF1-AS1, also known as FENDRR, could sensitize doxorubicin-resistance of OS cells through down-regulating ABCB1 and ABCC1. Here in, the critical role of FOXF1-AS1 in regulating OS progression was further investigated. Firstly, we found that FOXF1-AS1 and its antisense transcript FOXF1 expression were positively up-regulated in OS tissues and cell lines and correlated with poor prognosis of OS patients. Besides, FOXF1-AS1 as well as FOXF1 silencing significantly inhibited cell proliferation, migration, invasion of OS cells and tumor growth both in vitro and vivo through decreasing the expression of MMP2 and MMP9, whereas enhanced expression of FOXF1-AS1 had the opposite effects. In addition, mechanistically, both of FOXF1-AS1 and FOXF1 could regulate the expression of MMP2 and MMP9 at mRNA and protein levels, whereas FOXF1-AS1 could influence the FOXF1expression but FOXF1 did not have the same effect on FOXF1-AS1. Rescue assay further showed that FOXF1-AS1 overexpression efficiently reversed the knockdown of MMP2 and MMP9 expression induced by si-FOXF1. Thus, we concluded that FOXF1-AS1 may promote migration and invasion of OS cells through the FOXF1/MMP-2/-9 pathway. Taken together, these findings demonstrated the underlying mechanism of FOXF1-AS1 in the regulation of OS progression and provide a novel potential target in the OS therapy.




High PD-L1 Expression Is Closely Associated With Tumor-Infiltrating Lymphocytes and Leads to Good Clinical Outcomes in Chinese Triple Negative Breast Cancer Patients

2017

Background: To investigate the role of Programmed death ligand 1 (PD-L1) expression and tumor-infiltrating lymphocytes (TILs) in tumor recurrence and metastasis of Chinese patients suffering from triple negative breast cancer (TNBC).

Methods: PD-L1 immunohistochemistry was performed on 215 TNBCs. Also, the prevalence of TILs correlated the expression of PD-L1 and TILs with clinical outcomes. Kaplan-Meier and the model analyses of univariate Cox proportional hazards were utilized to compare the survival of patients with positive PD-L1 expression with those with negative PD-L1 expression.

Results: The median follow-up time was 67.7 months (range: 7-159 months). PD-L1-positive breast cancer patients had significantly longer disease-free survival (DFS) and Overall survival (OS) compared with PD-L1-negative patients (P=0.046; P=0.019) in TNBC. The presence of increased stromal lymphocytic infiltrates (STILs) was significantly associated with overall survival (P=0.026). The model analysis of univariate Cox proportional hazards showed that PD-L1 and STILs were independent prognostic factors for tumor prognosis.

Conclusions: Our study found that high levels of PD-L1 could be expressed in TNBC, which was correlated with the prevalence of TILs.




Fibroblast Growth Factor Receptor 2 Signaling in Breast Cancer

2017

Fibroblast growth factor receptor 2 (FGFR2) is a membrane-spanning tyrosine kinase that mediates signaling for FGFs. Recent studies detected various point mutations of FGFR2 in multiple types of cancers, including breast cancer, lung cancer, gastric cancer, uterine cancer and ovarian cancer, yet the casual relationship between these mutations and tumorigenesis is unclear. Here we will discuss possible interactions between FGFR2 signaling and several major pathways through which the aberrantly activated FGFR2 signaling may result in breast cancer development. We will also discuss some recent developments in the discovery and application of therapies and strategies for breast cancers by inhibiting FGFR2 activities.




Skeletal Muscle-Specific Overexpression of PGC-1α Induces Fiber-Type Conversion through Enhanced Mitochondrial Respiration and Fatty Acid Oxidation in Mice and Pigs

2017

Individual skeletal muscles in the animal body are heterogeneous, as each is comprised of different fiber types. Type I muscle fibers are rich with mitochondria, and have high oxidative metabolisms while type IIB fibers have few mitochondria and high glycolytic metabolic capacity. Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), a transcriptional co-activator that regulates mitochondrial biogenesis and respiratory function, is implicated in muscle fiber-type switching. Over-expression of PGC-1α in transgenic mice increased the proportion of red/oxidative type I fiber. During pig muscle growth, an increased number of type I fibers can give meat more red color. To explore the roles of PGC-1α in regulation of muscle fiber type conversion, we generated skeletal muscle-specific PGC-1α transgenic mice and pig. Ectopic over-expression of PGC-1α was detected in both fast and slow muscle fibers. The transgenic animals displayed a remarkable amount of red/oxidative muscle fibers in major skeletal muscle tissues. Skeletal muscles from transgenic mice and pigs have increased expression levels of oxidative fiber markers such as MHC1, MHC2x, myoglobin and Tnni1, and decreased expressions of glycolytic fiber genes (MHC2a, MHC2b, CASQ-1 and Tnni2). The genes responsible for the TCA cycle and oxidative phosphorylation, cytochrome coxidase 2 and 4, and citrate synthase were also increased in the transgenic mice and pigs. These results suggested that transgenic over-expressed PGC-1α significantly increased muscle mitochondrial biogenesis, resulting in qualitative changes from glycolytic to oxidative energy generation. The transgenic animals also had elevated levels of PDK4 and PPARγ proteins in muscle tissue, which can lead to increased glycogen deposition and fatty acid oxidation. Therefore, the results support a significant role of PGC-1α in conversion of fast glycolytic fibers to slow and oxidative fiber through enhanced mitochondrial respiration and fatty acid oxidation, and transgenic over-expression of PGC-1α in skeletal muscle leads to more red meat production in pigs.




Effect of Population Size and Mutation Rate on the Evolution of RNA Sequences on an Adaptive Landscape Determined by RNA Folding

2017

The dynamics of populations evolving on an adaptive landscape depends on multiple factors, including the structure of the landscape, the rate of mutations, and effective population size. Existing theoretical work often makes ad hoc and simplifying assumptions about landscape structure, whereas experimental work can vary important parameters only to a limited extent. We here overcome some of these limitations by simulating the adaptive evolution of RNA molecules, whose fitness is determined by the thermodynamics of RNA secondary structure folding. We study the influence of mutation rates and population sizes on final mean population fitness, on the substitution rates of mutations, and on population diversity. We show that evolutionary dynamics cannot be understood as a function of mutation rate µ, population size N, or population mutation rate alone. For example, at a given mutation rate, clonal interference prevents the fixation of beneficial mutations as population size increases, but larger populations still arrive at a higher mean fitness. In addition, at the highest population mutation rates we study, mean final fitness increases with population size, because small populations are driven to low fitness by the relatively higher incidence of mutations they experience. Our observations show that mutation rate and population size can interact in complex ways to influence the adaptive dynamics of a population on a biophysically motivated fitness landscape.




Host Cell Vimentin Restrains Toxoplasma gondii Invasion and Phosphorylation of Vimentin is Partially Regulated by Interaction with TgROP18

2017

The obligate intracellular parasite, Toxoplasma gondii, manipulates the cytoskeleton of its host cells to facilitate infection. A significant rearrangement of host cell vimentin around Toxoplasma parasitophorous vacuoles is observed during the course of infection. ROP18 (TgROP18) is a serine-threonine kinase secreted by T. gondii rhoptry and a major virulence factor; however, the mechanisms by which this kinase modulates host factors remain poorly understood. Different and dynamic patterns of vimentin solubility, phosphorylation, and expression levels were observed in host cells infected with T. gondii strain RH and RH Δrop18 strains, suggesting that TgROP18 contributes to the regulation of these dynamic patterns. Additionally, host cell vimentin was demonstrated to interact with and be phosphorylated by TgROP18. A significant increase in T. gondii infection rate was observed in vimentin knockout human brain microvessel endothelial cells (HBMEC), while vimentin knockout or knock down in host cells had no impact on parasite proliferation and egress. These results indicate that host cell vimentin can inhibit T. gondii invasion. Interestingly, western blotting of different mouse tissues indicated that the lowest vimentin expression level was present in the brain, which may explain the mechanism underlying the nervous system tropism of T. gondii, and the phenomenon of huge cyst burdens developing in the mouse brain during chronic infection.




The Emerging Roles of Microparticles in Diabetic Nephropathy

2017

Microparticles (MPs) are a type of extracellular vesicles (EVs) shed from the outward budding of plasma membranes during cell apoptosis and/or activation. These microsized particles then release specific contents (e.g., lipids, proteins, microRNAs) which are active participants in a wide range of both physiological and pathological processes at the molecular level, e.g., coagulation and angiogenesis, inflammation, immune responses. Research limitations, such as confusing nomenclature and overlapping classification, have impeded our comprehension of these tiny molecules. Diabetic nephropathy (DN) is currently the greatest contributor to end-stage renal diseases (ESRD) worldwide, and its public health impact will continue to grow due to the persistent increase in the prevalence of diabetes mellitus (DM). MPs have recently been considered as potentially involved in DN onset and progression, and this review juxtaposes some of the research updates about the possible mechanisms from several relevant aspects and insights into the therapeutic perspectives of MPs in clinical management and pharmacological treatment of DN patients.




Mesenchymal Stem Cell-Dependent Modulation of Liver Diseases

2017

Acute liver failure and cirrhosis display sequential and overlapping severe pathogenic processes that include inflammation, hepatocyte necrosis, and fibrosis, carrying a high mortality rate. Mesenchymal stem cells (MSCs) are a heterogeneous subset of stromal stem cells with immunonodulatory characteristics. MSCs are considered to act through multiple mechanisms to coordinate a dynamic, integrated response to liver inflammation and fibrosis, which prevents the progressive distortion of hepatic architecture. Accordingly, MSCs as well as their products have been investigated as a novel therapeutic approach for the treatment of inflammatory and fibrotic liver diseases.

In this review, we highlight the current findings on the MSC-based modulation of liver inflammation and fibrosis, and the possible use of MSCs in the therapy of immune-mediated liver pathology. We briefly describe the cellular and molecular mechanisms involved in MSC-dependent modulation of cytokine production, phenotype and function of liver infiltrated inflammatory cells and compare effects of engrafted MSCs versus MSC-generated conditioned medium (MSC-CM) in the therapy of acute liver injury. In order to elucidate therapeutic potential of MSCs and their products in modulation of chronic liver inflammation and fibrosis, we present the current findings regarding pathogenic role of immune cells in liver fibrosis and describe mechanisms involved in MSC-dependent modulation of chronic liver inflammation with the brief overview of on-going and already published clinical trials that used MSCs for the treatment of immune mediated chronic liver diseases. The accumulating evidence shows that MSCs had a significant beneficial effect in the treatment of immune-mediated liver diseases.




In Utero Alcohol Exposure and the Alteration of Histone Marks in the Developing Fetus: An Epigenetic Phenomenon of Maternal Drinking

2017

Ethanol is well known for its teratogenic effects during fetal development. Maternal alcohol consumption allows the developing fetus to experience the detrimental effects of alcohol exposure. Alcohol-mediated teratogenic effects can vary based on the dosage and the length of exposure. The specific mechanism of action behind this teratogenic effect is still unknown. Previous reports demonstrated that alcohol participates in epigenetic alterations, especially histone modifications during fetal development. Additional research is necessary to understand the correlation between major epigenetic events and alcohol-mediated teratogenesis such as that observed in fetal alcohol spectrum disorder (FASD). Here, we attempted to collect all the available information concerning alcohol-mediated histone modifications during gestational fetal development. We hope that this review will aid researchers to further examine the issues associated with ethanol exposure.




Structural Maintenance of Chromosomes protein 1: Role in Genome Stability and Tumorigenesis

2017

SMC1 (Structural Maintenance of Chromosomes protein 1), well known as one of the SMC superfamily members, has been explored to function in many activities including chromosome dynamics, cell cycle checkpoint, DNA damage repair and genome stability. Upon being properly assembled as part of cohesin, SMC1 can be phosphorylated by ATM and mediate downstream DNA damage repair after ionizing irradiation. Abnormal gene expression or mutation of SMC1 can cause defect in the DNA damage repair pathway, which has been strongly associated with tumorigenesis. Here we focus to discuss SMC1's role in genome stability maintenance and tumorigenesis. Deciphering the underlying molecular mechanism can provide insight into novel strategies for cancer treatment.




Spatiotemporal Expression of Wnt/β-catenin Signaling during Morphogenesis and Odontogenesis of Deciduous Molar in Miniature Pig

2017

The canonical Wnt/β-catenin signaling pathway has been shown to play essential roles in tooth initiation and early tooth development. However, the role of Wnt/β-catenin signaling in cusp patterning and crown calcification in large mammals are largely unknown. In our previous study, miniature pigs were used as the animal model due to the similarity of tooth anatomy and replacement pattern between miniature pig and human. Dynamic gene expression of third deciduous molar (DM3) in miniature pig at early stages was profiled using microarray method and expression of Wnt genes was significantly correlate with odontogenesis. In the present study, dynamic expression patterns of Wnt/β-catenin signaling genes of DM3 at cap, early bell and late bell (secretory) stage were identified. We found that Lef1 and Axin2 were expressed in the enamel knot and underlying mesenchyme regions. Meanwhile, Dkk1 was expressed in the peripheral and lower parts of dental papilla, thus forming the potential Wnt signaling gradient. We also found that β-Catenin, Axin2 and Lef1 were expressed strongly in undifferentiated cells of the inner enamel epithelium (IEE), but weakly in differentiated ameloblasts. Furthermore, we found that both Wnt signaling read-out gene Lef1 and the inhibitor Dkk1 were co-expressed in the pre-odontoblasts. In conclusion, the spatiotemporal distribution and potential gradient of Wnt signaling may contribute to cusp patterning and crown calcification. These data may yield insight into future study of precise control of crown morphogenesis and regeneration in large mammals.




Activation of Nrf2 Attenuates Pulmonary Vascular Remodeling via Inhibiting Endothelial-to-Mesenchymal Transition: an Insight from a Plant Polyphenol

2017

The endothelial-to-mesenchymal transition (EndMT) has been demonstrated to be involved in pulmonary vascular remodeling. It is partly attributed to oxidative and inflammatory stresses in endothelial cells. In current study, we conducted a series of experiments to clarify the effect of salvianolic acid A (SAA), a kind of polyphenol compound, in the process of EndMT in human pulmonary arterial endothelial cells and in vivo therapeutic efficacy on vascular remodeling in monocrotaline (MCT)-induced EndMT. EndMT was induced by TGFβ1 in human pulmonary arterial endothelial cells (HPAECs). SAA significantly attenuated EndMT, simultaneously inhibited cell migration and reactive oxygen species (ROS) formation. In MCT-induced pulmonary arterial hypertension (PAH) model, SAA improved vascular function, decreased TGFβ1 level and inhibited inflammation. Mechanistically, SAA stimulated Nrf2 translocation and subsequent heme oxygenase-1 (HO-1) up-regulation. The effect of SAA on EndMT in vitro was abolished by ZnPP, a HO-1 inhibitor. In conclusion, this study indicates a deleterious impact of oxidative stress on EndMT. Polyphenol antioxidant treatment may provide an adjunctive action to alleviate pulmonary vascular remodeling via inhibiting EndMT.




Alkbh4 and Atrn Act Maternally to Regulate Zebrafish Epiboly

2017

During embryonic gastrulation, coordinated cell movements occur to bring cells to their correct position. Among them, epiboly produces the first distinct morphological changes, which is essential for the early development of zebrafish. Despite its fundamental importance, little is known to understand the underlying molecular mechanisms. By generating maternal mutant lines with CRISPR/Cas9 technology and using morpholino knockdown strategy, we showed that maternal Alkbh4 depletion leads to severe epiboly defects in zebrafish. Immunofluorescence assays revealed that Alkbh4 promotes zebrafish embryonic epiboly through regulating actomyosin contractile ring formation, which is composed of Actin and non-muscular myosin II (NMII). To further investigate this process, yeast two hybridization assay was performed and Atrn was identified as a binding partner of Alkbh4. Combining with the functional results of Alkbh4, we found that maternal Atrn plays a similar role in zebrafish embryonic morphogenesis by regulating actomyosin formation. On the molecular level, our data revealed that Atrn prefers to interact with the active form of Alkbh4 and functions together with it to regulate the demethylation of Actin, the actomyosin formation, and subsequently the embryonic epiboly.




DNA Methylation Mediated Downregulation of miR-449c Controls Osteosarcoma Cell Cycle Progression by Directly Targeting Oncogene c-Myc

2017

MicroRNAs (miRNAs) are critical regulators of gene expression, and they have broad roles in the pathogenesis of different diseases including cancer. Limited studies and expression profiles of miRNAs are available in human osteosarcoma cells. By applying a miRNA microarray analysis, we observed a number of miRNAs with abnormal expression in cancerous tissues from osteosarcoma patients. Of particular interest in this study was miR-449c, which was significantly downregulated in osteosarcoma cells and patients, and its expression was negatively correlated with tumor size and tumor MSTS stages. Ectopic expression of miR-449c significantly inhibited osteosarcoma cell proliferation and colony formation ability, and caused cell cycle arrest at the G1 phase. Further analysis identified that miR-449c was able to directly target the oncogene c-Myc and negatively regulated its expression. Overexpression of c-Myc partially reversed miR-449c-mimic-inhibited cell proliferation and colony formation. Moreover, DNA hypermethylation was observed in two CpG islands adjacent to the genomic locus of miR-449c in osteosarcoma cells. Conversely, treatment with the DNA methylation inhibitor AZA caused induction of miR-449c. In conclusion, our results support a model that DNA methylation mediates downregulation of miR-449c, diminishing miR-449c mediated inhibition of c-Myc and thus leading to the activation of downstream targets, eventually contributing to osteosarcoma tumorigenesis.




FGFR3 deficient mice have accelerated fracture repair

2017

Bone fracture healing is processed through multiple biological stages that partly recapitulates the skeletal development process. FGFR3 is a negative regulator of chondrogenesis during embryonic stage and plays an important role in both chondrogenesis and osteogenesis. We have investigated the role of FGFR3 in fracture healing using unstabilized fracture model and found that gain-of-function mutation of FGFR3 inhibits the initiation of chondrogenesis during cartilage callus formation. Here, we created closed, stabilized proximal tibia fractures with an intramedullary pin in Fgfr3-/-mice and their littermate wild-type mice. Fracture healing was evaluated by radiography, micro-CT, histology, and real-time polymerase chain reaction (RT-PCR) analysis. The fractured Fgfr3-/- mice had increased formation of cartilaginous callus, more fracture callus, and more rapid endochondral ossification in fracture sites with up-regulated expressions of chondrogenesis related gene. The fractures of Fgfr3-/- mice healed faster with accelerated fracture callus mineralization and up-regulated expression of osteoblastogenic genes. The healing of fractures in Fgfr3-/- mice was accelerated in the stage of formation of cartilage and endochondral ossification. Downregulation of FGFR3 activity can be considered as a potential bio-therapeutic strategy for fracture treatment.




Functional Analysis of a Novel FOXL2 Indel Mutation in Chinese Families with Blepharophimosis-Ptosis-Epicanthus Inversus Syndrome Type I

2017

Background: Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is an autosomal dominant disease with a low incidence rate. Indel mutations in the forkhead box L2 (FOXL2) gene cause two types of BPES that are distinguished by the presence (type I) or absence (type II) of premature ovarian failure (POF). The purpose of this study was to identify a possible deletion in FOXL2 in Chinese families with BPES and to clarify its relationship with POF.

Methods: An autosomal dominant Chinese BPES family with four generations was enrolled in this study. Peripheral venous blood was collected from all affected patients, and genomic DNA was extracted from leukocytes. The whole coding sequence and nearby 5' untranslated region (UTR) and 3'UTR of the FOXL2 gene were amplified using polymerase chain reaction (PCR) with three sets of overlapping primers, followed by sequencing analyses. The sequencing results were analysed using SeqMan software. Based on the patients' clinical manifestations and analysis of the identified indel mutation, we found that the mutation disturbed interactions between FOXL2 and the StAR gene. Furthermore, through subcellular localisation and functional studies, we observed significant mislocalisation of the mutant protein; the mutant protein was found in the cytoplasm, while the wild-type protein was found in the nucleus. Loss of function was confirmed by transcriptional activity assays, quantitative real-time PCR, and electrophoretic mobility shift assays.

Results: All affected patients presented with clinical features of BPES type I, including small palpebral fissures, ptosis, telecanthus, and epicanthus inversus with POF. A novel FOXL2 heterozygous indel mutation, c.19_95del, a 77-bp deletion that disrupts FOXL2 protein structure, was identified in all affected members of the family. In addition, this indel mutation significantly increased StAR mRNA expression by disrupting the ability of the FOXL2 protein to bind to the StAR promoter and act as a repressor of this gene.

Conclusions: A novel FOXL2 indel mutation was identified in Chinese families with BPES. Our results expand the spectrum of known FOXL2 mutations and provide additional insight into the structure-function relationships of the FOXL2 protein. Furthermore, this novel mutation resulted in the dysfunction of FOXL2 as a transcription factor, blocking its ability to bind to the promoter region of the StAR gene, resulting in POF in the affected patient.




Linker Histone in Diseases

2017

The linker histone is a protein that binds with the nucleosome, which is generally considered to achieve chromatin condensation in the nucleus. Accumulating evidences suggest that the linker histone is essential in the pathogenesis of several diseases. In this review, we briefly introduce the current knowledge of the linker histone, including its structure, characteristics and functions. Also, we move forward to present the advances of the linker histone's association with certain diseases, such as cancer, Alzheimer's disease, infection, male infertility and aberrant immunity situations, focusing on the alteration of the linker histone under certain pathological conditions and its role in developing each disease.




Osthole Promotes Bone Fracture Healing through Activation of BMP Signaling in Chondrocytes

2017

Osthole is a bioactive coumarin derivative and has been reported to be able to enhance bone formation and improve fracture healing. However, the molecular mechanism of Osthole in bone fracture healing has not been fully defined. In this study we determined if Osthole enhances bone fracture healing through activation of BMP2 signaling in mice. We performed unilateral open transverse tibial fracture procedure in 10-week-old C57BL/6 mice which were treated with or without Osthole. Our previous studies demonstrated that chondrocyte BMP signaling is required for bone fracture healing, in this study we also performed tibial fracture procedure in Cre-negative and Col2-Cre;Bmp2flox/flox conditional knockout (KO) mice (Bmp2Col2Cre) to determine if Osthole enhances fracture healing in a BMP2-dependent manner. Fracture callus tissues were collected and analyzed by X-ray, micro-CT (μCT), histology, histomorphometry, immunohistochemistry (IHC), biomechanical testing and quantitative gene expression analysis. In addition, mouse chondrogenic ATDC5 cells were cultured with or without Osthole and the expression levels of chondrogenic marker genes were examined. The results demonstrated that Osthole promotes bone fracture healing in wild-type (WT) or Cre- control mice. In contrast, Osthole failed to promote bone fracture healing in Bmp2Col2Cre conditional KO mice. In the mice receiving Osthole treatment, expression of cartilage marker genes was significantly increased. We conclude that Osthole could promote bone strength and enhance fracture healing by activation of BMP2 signaling. Osthole may be used as an alternative approach in the orthopaedic clinic for the treatment of fracture healing.




Intracellular Insulin and Impaired Autophagy in a Zebrafish model and a Cell Model of Type 2 diabetes

2017

Type 2 diabetes mellitus is characterized by insulin resistance. However, the complete molecular mechanism remains unclear. In this study, zebrafish were fed a long-term high-fat diet to induce type 2 diabetes, which resulted in a higher body weight, body mass index, more lipid vacuoles in liver, increased insulin transcription level in liver, brain and muscle, and high fasting blood glucose in the high-fat diet zebrafish. Oppositely, the transcription levels of insulin substrate-2 and glucose transporter 2 were significantly decreased, indicating insulin signaling pathway and glucose transport impaired in the insulin-targeting tissues. Transcription of the autophagy-related genes, ATG3, ATG4B, ATG5, ATG7, ATG12, and FOXO3, were decreased but autophagy inhibitor gene m-TOR increased, and autophagy-flux was inhibited in liver of the high-fat diet zebrafish. Main of these changes were confirmed in palmitic acid-treated HepG2 cells. Further, in co-immunoprecipitation and subcellular co-localization experiments, the conjunction of preproinsulin with cargo-recognition protein p62 increased, but conjuncts of autophagosome with p62-cargo, lysosomes with p62-cargo, and autolysosomes decreased apparently. Interestingly, lysosomes, autolysosomes and conjuncts of p62-insulin localized at the periphery of palmitic acid-treated cells, the margination of lysosomes may mediate deactivation of proteases activity. These findings suggest that intracellular high-lipid may trigger defective autophagy, defective downstream signaling of insulin and accumulated intracellular preproinsulin, leading to dysregulation of cell homeostasis mechanism, which may be one of reasons involved in insulin-resistance in type 2 diabetes.




The Overexpression of CARM1 Promotes Human Osteosarcoma Cell Proliferation through the pGSK3β/β-Catenin/cyclinD1 Signaling Pathway

2017

Osteosarcoma (OS) is a kind of malignant bone tumor that occurs frequently in the region surrounding the knee joint and poses a threat to the health of teenagers. Since the application of chemotherapy to treat OS, 5-year survival rate in patients has improved from 10% to 70%, but patient survival has not changed over the past four decades. Coactivator-associated arginine methyltransferase 1 (CARM1) is a member of the PRMT protein family; it acts as an oncogene in many cancers, but its function in OS is still unknown. In this study, we found that CARM1 is overexpressed in OS and its expression is correlated with the Enneking stage. CCK-8 and colony forming assays showed that proliferation in OS cell lines was downregulated when siRNA was used to knockdown CARM1 expression. The cell cycle was inhibited in S phase after si-CARM1 transfection in OS cell lines. An antibody array indicated that Erk1/2 (Thr202/Tyr204), PARS40 (Thr246), and GSK3β (Ser9) expression are affected by CARM1, and western blotting verified that CARM1 promotes OS cell proliferation via pGSK3β/β-catenin/cyclinD1 signaling. Accordingly, CARM1 is a crucial gene in OS and is a potential new treatment target.




Vasopressin Mediates the Renal Damage Induced by Limited Fructose Rehydration in Recurrently Dehydrated Rats

2017

Recurrent dehydration and heat stress cause chronic kidney damage in experimental animals. The injury is exacerbated by rehydration with fructose-containing beverages. Fructose may amplify dehydration-induced injury by directly stimulating vasopressin release and also by acting as a substrate for the aldose reductase-fructokinase pathway, as both of these systems are active during dehydration. The role of vasopressin in heat stress associated injury has not to date been explored. Here we show that the amplification of renal damage mediated by fructose in thermal dehydration is mediated by vasopressin. Fructose rehydration markedly enhanced vasopressin (copeptin) levels and activation of the aldose reductase-fructokinase pathway in the kidney. Moreover, the amplification of the renal functional changes (decreased creatinine clearance and tubular injury with systemic inflammation, renal oxidative stress, and mitochondrial dysfunction) were prevented by the blockade of V1a and V2 vasopressin receptors with conivaptan. On the other hand, there are also other operative mechanisms when water is used as rehydration fluid that produce milder renal damage that is not fully corrected by vasopressin blockade. Therefore, we clearly showed evidence of the cross-talk between fructose, even at small doses, and vasopressin that interact to amplify the renal damage induced by dehydration. These data may be relevant for heat stress nephropathy as well as for other renal pathologies due to the current generalized consumption of fructose and deficient hydration habits.




Current Progresses of Single Cell DNA Sequencing in Breast Cancer Research

2017

Breast cancers display striking genetic and phenotypic diversities. To date, several hypotheses are raised to explain and understand the heterogeneity, including theories for cancer stem cell (CSC) and clonal evolution. According to the CSC theory, the most tumorigenic cells, while maintaining themselves through symmetric division, divide asymmetrically to generate non-CSCs with less tumorigenic and metastatic potential, although they can also dedifferentiate back to CSCs. Clonal evolution theory recapitulates that a tumor initially arises from a single cell, which then undergoes clonal expansion to a population of cancer cells. During tumorigenesis and evolution process, cancer cells undergo different degrees of genetic instability and consequently obtain varied genetic aberrations. Yet the heterogeneity in breast cancers is very complex, poorly understood and subjected to further investigation. In recent years, single cell sequencing (SCS) technology developed rapidly, providing a powerful new way to better understand the heterogeneity, which may lay foundations to some new strategies for breast cancer therapies. In this review, we will summarize development of SCS technologies and recent advances of SCS in breast cancer.




Structure elucidation and antitumor activity of a new polysaccharide from Maerkang Tricholoma matsutake

2017

A new heteropolysaccharide was isolated from the fruiting bodies of Tricholoma matsutake which had a molecular weight of 12078 Da. The results of structural features analysis showed that T. matsutake polysaccharide, here named TMP-B, was mainly composed of α - D - glucose and α - D - galactose which ratios were 7:2 and had a backbone of 1, 4 - linked α - D - glucose which branches were mainly composed of two 6 - linked α - D - galactose residue, and the α - D - galactose was 1, 6 - linked. Antitumor activity results showed that heteropolysaccharide TMP-B could inhibit the growth of S180 tumor in vivo and promote the apoptosis of L929 cells in vitro. Immunoregulatory activity results showed that TMP-B could promote the proliferation of macrophages by affecting G0/G1 phase, S phases and G2/M phases and promote cytokines release and gene expression. The result of this study introduced Maerkang T. matsutake as a possible valuable source which helped to exhibit unique antitumor and immunoregulatory properties.




Acetylation of hMOF Modulates H4K16ac to Regulate DNA Repair Genes in Response to Oxidative Stress

2017

Oxidative stress is considered to be a key risk state for a variety of human diseases. In response to oxidative stress, the regulation of transcriptional expression of DNA repair genes would be important to DNA repair and genomic stability. However, the overall pattern of transcriptional expression of DNA repair genes and the underlying molecular response mechanism to oxidative stress remain unclear. Here, by employing colorectal cancer cell lines following exposure to hydrogen peroxide, we generated expression profiles of DNA repair genes via RNA-seq and identified gene subsets that are induced or repressed following oxidative stress exposure. RRBS-seq analyses further indicated that transcriptional regulation of most of the DNA repair genes that were induced or repressed is independent of their DNA methylation status. Our analyses also indicate that hydrogen peroxide induces deacetylase SIRT1 which decreases chromatin affinity and the activity of histone acetyltransferase hMOF toward H4K16ac and results in decreased transcriptional expression of DNA repair genes. Taken together, our findings provide a potential mechanism by which oxidative stress suppresses DNA repair genes which is independent of the DNA methylation status of their promoters.




In Search for Pheromone Receptors: Certain Members of the Odorant Receptor Family in the Desert Locust Schistocerca gregaria (Orthoptera: Acrididae) Are Co-expressed with SNMP1

2017

Under given environmental conditions, the desert locust (Schistocera gregaria) forms destructive migratory swarms of billions of animals, leading to enormous crop losses in invaded regions. Swarm formation requires massive reproduction as well as aggregation of the animals. Pheromones that are detected via the olfactory system have been reported to control both reproductive and aggregation behavior. However, the molecular basis of pheromone detection in the antennae of Schistocerca gregaria is unknown. As an initial step to disclose pheromone receptors, we sequenced the antennal transcriptome of the desert locust. By subsequent bioinformatical approaches, 119 distinct nucleotide sequences encoding candidate odorant receptors (ORs) were identified. Phylogenetic analyses employing the identified ORs from Schistocerca gregaria (SgreORs) and OR sequences from the related species Locusta migratoria revealed a group of locust ORs positioned close to the root, i.e. at a basal site in a phylogenetic tree. Within this particular OR group (termed basal or b-OR group), the locust OR sequences were strictly orthologous, a trait reminiscent of pheromone receptors from lepidopteran species. In situ hybridization experiments with antennal tissue demonstrated expression of b-OR types from Schistocerca gregaria in olfactory sensory neurons (OSNs) of either sensilla trichodea or sensilla basiconica, both of which have been reported to respond to pheromonal substances. More importantly, two-color fluorescent in situ hybridization experiments showed that most b-OR types were expressed in cells co-expressing the “sensory neuron membrane protein 1” (SNMP1), a marker indicative of pheromone-sensitive OSNs in insects. Analyzing the expression of a larger number of SgreOR types outside the b-OR group revealed that only a few of them were co-expressed with SNMP1.

In summary, we have identified several candidate pheromone receptors from Schistocerca gregaria that could mediate responses to pheromones implicated in controlling reproduction and aggregation behavior.




Lycium Barbarum Polysaccharides Decrease Hyperglycemia-Aggravated Ischemic Brain Injury through Maintaining Mitochondrial Fission and Fusion Balance

2017

Although it has been reported that polysaccharides found in Lycium barbarum possess neuroprotective effects, little is known of their ability to ameliorate hyperglycemia-aggravated ischemia/reperfusion brain injury. In this study, normoglycemic (NG) and hyperglycemic (HG) rats were compared after 30 minutes of middle cerebral artery occlusion (MCAO), followed by 24 or 27 hours of reperfusion, with HG rats pretreated with lyceum barbarum polysaccharides (LBP) or insulin. In each group, the neurological deficit, infarct volume, pathohistology, and expression of proteins, Opa1 and Drp1, were assessed to determine the efficacy of LBP in alleviating hyperglycemia-aggravated ischemia/reperfusion brain injury. Our results show that, compared to the NG group, the HG group had increases in neurological deficits, infarct volume, and evidence of neuronal pyknosis at 24- and/or 72-h of reperfusion (P<0.05) and that pre-treatment with LBP decreased these effects (P<0.05). In addition, immunohistochemistry revealed an increase of Drp1 and a decrease of Opa1 positive neurons in the HG group after 24 and 72 hours of reperfusion when compared to the NG group. LBP treatment prevented the HG-induced alterations in Drp-1 and Opa1 expression. Western blots further confirmed these findings showing that HG caused an increase in phospho-Drp1 and a decrease in Opa1 which were subsequently reversed by LBP addition. These results suggest that hyperglycemia-aggravated ischemic brain damage is associated with an alteration of mitochondrial dynamics and that pre-treatment with LBP ameliorates the hyperglycemia-enhanced ischemic brain damage through maintaining mitochondrial dynamic balance.




Crosstalk between Mitochondrial Fission and Oxidative Stress in Paraquat-Induced Apoptosis in Mouse Alveolar Type II Cells

2017

Paraquat (PQ), as a highly effective and nonselective herbicide, induces cell apoptosis through generation of superoxide anions which forms reactive oxygen species (ROS). Mitochondria, as regulators for cellular redox signaling, have been proved to play an important role in PQ-induced cell apoptosis. This study aimed to evaluate whether and how mitochondrial fission interacts with oxidative stress in PQ-induced apoptosis in mouse alveolar type II (AT-II) cells. Firstly, we demonstrated that PQ promoted apoptosis and release of cytochrome-c (Cyt-c). Furthermore, we showed that PQ broke down mitochondrial network, enhanced the expression of fission-related proteins, increased Drp1 mitochondrial translocation while decreased the expression of fusion-related proteins in AT-II cells. Besides, inhibiting mitochondrial fission using mdivi-1, a selective inhibitor of Drp1, markedly attenuated PQ-induced apoptosis, release of Cyt-c and the generation of ROS. These results indicate that mitochondrial fission involves in PQ-induced apoptosis. Further study demonstrated that antioxidant ascorbic acid inhibited Drp1 mitochondrial translocation, mitochondrial fission and attenuated PQ-induced apoptosis. Overall, our findings suggest that mitochondrial fission interplays with ROS in PQ-induced apoptosis in mouse AT-II cells and mitochondrial fission could serve as a potential therapeutic target in PQ poisoning.




Inhibition of mTOR signaling Confers Protection against Cerebral Ischemic Injury in Acute Hyperglycemic Rats

2017

Hyperglycemia is known to exacerbate neuronal death resulted from cerebral ischemia. The mechanisms are not fully understood. The mammalian target of rapamycin (mTOR) pathway regulates cell growth, division and apoptosis. Recent studies suggest that activation of mTOR may mediate ischemic brain damage. The objective of the present experiment is to explore whether mTOR mediates ischemic brain damage in acute hyperglycemic animals. Rats were subjected to 10 min of forebrain ischemia under euglycemic, hyperglycemic and rapamycin-treated hyperglycemic conditions. The rat brain samples were collected from the cortex and hippocampi after 3h and 16h of reperfusion. The results showed that hyperglycemia significantly increased neuronal death in the cortex and hippocampus and the exacerbation effect of hyperglycemia was associated with further activation of mTOR under control and/or ischemic conditions. Inhibition of mTOR with rapamycin ameliorated the damage and suppressed hyperglycemia-elevated p-MTOR, p-P70S6K and p-S6. In addition, hyperglycemia per se increased the levels of cytosolic cytochrome c and autophagy marker LC3-II, while rapamycin alleviated these alterations. It is concluded that activation of mTOR signaling may play a detrimental role in mediating the aggravating effect of hyperglycemia on cerebral ischemia.




Exposure to Concentrated Ambient Fine Particulate Matter Induces Vascular Endothelial Dysfunction via miR-21

2017

Vascular endothelial permeability transition does not cause significant lesions, but enhanced permeability may contribute to the development of vascular and other diseases, including atherosclerosis, hypertension, heart failure and cancer. Therefore, elucidating the effect of Particulate Matter 2.5 (PM2.5) on vascular endothelial permeability could help prevent disease that might be caused by PM2.5. Our previous study and the present one revealed that PM2.5 significantly increased the permeability of vascular endothelial cells and disrupted the barrier function of the vascular endothelium in Sprague Dawley (SD) rats. We found that the effect occurred mainly through induction of signal transducer and activator of transcription 3 (STAT3) phosphorylation, further transcriptional regulation of microRNA21 (miR-21) and promotion of miR-21 expression. These changes post-transcriptionally repress tissue inhibitor of metalloproteinases 3 (TIMP3) and promote matrix metalloproteinases 9 (MMP9) expression. This work provides evidence that PM2.5 exerts direct inhibitory action on vascular endothelial barrier function and might give rise to a number of vascular diseases.




Emerging roles of SIRT1 in fatty liver diseases

2017

Fatty liver diseases, which are commonly associated with high-fat/calorie diet, heavy alcohol consumption and/or other metabolic disorder causes, lead to serious medical concerns worldwide in recent years. It has been demonstrated that metabolic homeostasis disruption is most likely to be responsible for this global epidemic. Sirtuins are a group of conserved nicotinamide adenine dinucleotide (NAD+) dependent histone and/or protein deacetylases belonging to the silent information regulator 2 (Sir2) family. Among seven mammalian sirtuins, sirtuin 1 (SIRT 1) is the most extensively studied one and is involved in both alcoholic and nonalcoholic fatty liver diseases. SIRT1 plays beneficial roles in regulating hepatic lipid metabolism, controlling hepatic oxidative stress and mediating hepatic inflammation through deacetylating some transcriptional regulators against the progression of fatty liver diseases. Here we summarize the latest advances of the biological roles of SIRT1 in regulating lipid metabolism, oxidative stress and inflammation in the liver, and discuss the potential of SIRT1 as a therapeutic target for treating alcoholic and nonalcoholic fatty liver diseases.




Down-regulation of aminopeptidase N and ABC transporter subfamily G transcripts in Cry1Ab and Cry1Ac resistant Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae)

2017

The Asian corn borer (ACB), Ostrinia furnacalis (Lepidoptera: Crambidae), is a highly destructive pest of cultivated maize throughout East Asia. Bacillus thuringiensis (Bt) crystalline protein (Cry) toxins cause mortality by a mechanism involving pore formation or signal transduction following toxin binding to receptors along the midgut lumen of susceptible insects, but this mechanism and mutations therein that lead to resistance are not fully understood. In the current study, quantitative comparisons were made among midgut expressed transcripts from O. furnacalis susceptible (ACB-BtS) and laboratory selected strains resistant to Cry1Ab (ACB-AbR) and Cry1Ac toxins (ACB-AcR) when feeding on non-Bt diet. From a combined de novo transcriptome assembly of 83,370 transcripts, ORFs of ≥ 100 amino acids were predicted and annotated for 28,940 unique isoforms derived from 12,288 transcripts. Transcriptome-wide expression estimated from RNA-seq read depths predicted significant down-regulation of transcripts for previously known Bt resistance genes, aminopeptidase N1 (apn1) and apn3, as well as a putative ATP binding cassette transporter group G (abcg) gene in both ACB-AbR and -AcR (log2[fold-change] ≥ 1.36; P < 0.0001). The transcripts that were most highly differentially regulated in both ACB-AbR and -AcR compared to ACB-BtS (log2[fold-change] ≥ 2.0; P < 0.0001) included up- and down-regulation of serine proteases, storage proteins and cytochrome P450 monooxygenases, as well as up-regulation of genes with predicted transport function. This study predicted the significant down-regulation of transcripts for previously known Bt resistance genes, aminopeptidase N1 (apn1) and apn3, as well as abccg gene in both ACB-AbR and -AcR. These data are important for the understanding of systemic differences between Bt resistant and susceptible genotypes.




Platelet-derived Extracellular Vesicles: An Emerging Therapeutic Approach

2017

Extracellular vesicles (EVs) are a newly-discovered way by which cells communicate with their neighbors, as well as transporting cargos which once were considered to be limited by membrane barriers, including membrane proteins, cytosolic proteins and RNA. The discovery of platelet-derived EVs (P-EVs), the most abundant EVs in human blood, has been a very tortuous process. At first, P-EVs were identified as nothing but 'platelet dust', and subsequent research did not progress smoothly because of the limited research techniques to study EVs. Following leaps and bounds of technical progress in studying EVs, more and more attractive features of P-EVs were revealed and they began to be further researched. The aim of this review is to present the latest knowledge about the role of P-EVs in tissue repair and tumor progression. The potential mechanism of P-EVs is emphasized. Then the limitations of the present study and future research directions are discussed.




FOXO Signaling Pathways as Therapeutic Targets in Cancer

2017

Many transcription factors play a key role in cellular differentiation and the delineation of cell phenotype. Transcription factors are regulated by phosphorylation, ubiquitination, acetylation/deacetylation and interactions between two or more proteins controlling multiple signaling pathways. These pathways regulate different physiological processes and pathological events, such as cancer and other diseases. The Forkhead box O (FOXO) is one subfamily of the fork head transcription factor family with important roles in cell fate decisions and this subfamily is also suggested to play a pivotal functional role as a tumor suppressor in a wide range of cancers. During apoptosis, FOXOs are involved in mitochondria-dependent and -independent processes triggering the expression of death receptor ligands like Fas ligand, TNF apoptosis ligand and Bcl‑XL, bNIP3, Bim from Bcl-2 family members. Different types of growth factors like insulin play a vital role in the regulation of FOXOs. The most important pathway interacting with FOXO in different types of cancers is the PI3K/AKT pathway. Some other important pathways such as the Ras-MEK-ERK, IKK and AMPK pathways are also associated with FOXOs in tumorigenesis. Therapeutically targeting the FOXO signaling pathway(s) could lead to the discovery and development of efficacious agents against some cancers, but this requires an enhanced understanding and knowledge of FOXO transcription factors and their regulation and functioning. This review focused on the current understanding of cell biology of FOXO transcription factors which relates to their potential role as targets for the treatment and prevention of human cancers. We also discuss drugs which are currently being used for cancer treatment along with their target pathways and also point out some potential drawbacks of those drugs, which further signifies the need for development of new drug strategies in the field of cancer treatment.




Stroma-derived Fibrinogen-like Protein 2 Activates Cancer-associated Fibroblasts to Promote Tumor Growth in Lung Cancer

2017

Fibrinogen-like protein 2 (Fgl2), a member of the fibrinogen super family, is a pleiotropic cytokine that impacts diverse cellular functions. Previous studies have shown that tumor cell-derived Fgl2 promotes tumorigenesis and metastasis in immune-deficient mice, and it also functions as an immune-suppressive modulator in glioblastoma multiform (GMB). This study aimed to evaluate whether and how tumor stroma-derived Fgl2 affects tumorigenesis and tumor progression. We established the syngeneic transplantable Lewis lung carcinoma (LLC) model in Fgl2-knock-out (Fgl2-KO) mice and we found that deficiency of host Fgl2 is associated with reduced growth of syngeneic LLC tumors. Furthermore, we confirmed that host Fgl2 deficiency significantly decreased the accumulation of myeloid-derived suppressor cells (MDSCs) through down-regulation of chemokine (C-X-C motif) ligand 12 (CXCL12) expression. More importantly, we demonstrated that Fgl2 induced an activated and pro-tumorigenic phenotype of cancer-associated fibroblasts (CAFs) which are the principal source of CXCL12 in the tumor microenvironment (TME). Our results present a novel role of stroma-derived Fgl2 in CAF activation and function, suggesting that Fgl2 is an effective therapeutic target for treating lung cancer.




Berberine Reverses Hypoxia-induced Chemoresistance in Breast Cancer through the Inhibition of AMPK- HIF-1α

2017

Breast cancer is the most common type of cancer and the second leading cause of cancer death in American women. Chemoresistance is common and inevitable after a variable period of time. Therefore, chemosensitization is a necessary strategy on drug-resistant breast cancer. In this study, MCF-7 breast cancer cell was cultured under hypoxia for a week to induce the resistance to doxorubincin (DOX). The effect of different doses of berberine, a traditional Chinese medicine, on DOX sensitivity to MFC-7/hypoxia cells was observed. We found that hypoxia increased DOX resistance on breast cancer cells with the AMPK activation. Low-dose berberine could resensitize DOX chemosensitivity in MCF-7/hypoxia cell, however, high-dose berberine directly induced apoptosis. The intriguing fact was that the protein expressions of AMPK and HIF-1α were down-regulated by berberine, either low dose or high dose. But the downstream of HIF-1α occurred the bifurcation dependent on the dosage of berberine: AMPK-HIF-1α-P-gp inactivation played a crucial role on the DOX chemosensitivity of low-dose berberine, while AMPK-HIF-1α downregulaton inducing p53 activation led to apoptosis in high-dose berberine. These results were consistent to the transplanted mice model bearing MCF-7 drug-resistance tumor treated by berberine combined with DOX or high-dose berberine alone. This work shed light on a potentially therapeutic attempt to overcome drug-resistant breast cancer.




Dioscin Induces Gallbladder Cancer Apoptosis by Inhibiting ROS-Mediated PI3K/AKT Signalling

2017

Gallbladder cancer (GBC), highly aggressive form of cancer with an extremely poor prognosis, is the most common malignancy of the biliary tract. In this study, we investigated the effects of dioscin (DSN) on human GBC and the potential mechanisms underlying these effects. The results showed that DSN significantly inhibited GBC cell proliferation and migration. Moreover, DSN induced GBC cell apoptosis via mitochondrial dependent apoptotic signalling. Reactive oxygen species (ROS) and glutathione (GSH) levels were measured, and ROS scavengers completely inhibited DSN-induced apoptosis and migration, indicating that ROS play an essential role in GBC progression. Western blot analysis showed that AKT activity was significantly downregulated after DSN treatment, and that inhibition/ectopic expression of AKT enhanced/abolished DSN-induced apoptosis but not migration. Furthermore, we confirmed the relationship between ROS and the PI3K/AKT pathway and found that DSN induced apoptosis by regulating ROS-mediated PI3K/AKT signaling. Taken together, these findings indicate that DSN induces GBC apoptosis through inhibiting ROS-mediated PI3K/AKT signalling.




Angiomotin Family Members: Oncogenes or Tumor Suppressors?

2017

Angiomotin (Amot) family contains three members: Amot (p80 and p130 isoforms), Amot-like protein 1 (Amotl1), and Amot-like protein 2 (Amotl2). Amot proteins play an important role in tube formation and migration of endothelial cells and the regulation of tight junctions, polarity, and epithelial-mesenchymal transition in epithelial cells. Moreover, these proteins regulate the proliferation and migration of cancer cells. In most cancers, Amot family members promote the proliferation and invasion of cancer cells, including breast cancer, osteosarcoma, colon cancer, prostate cancer, head and neck squamous cell carcinoma, cervical cancer, liver cancer, and renal cell cancer. However, in glioblastoma, ovarian cancer, and lung cancer, Amot inhibits the growth of cancer cells. In addition, there are controversies on the regulation of Yes-associated protein (YAP) by Amot. Amot promotes either the internalization of YAP into the nucleus or the retention of YAP in the cytoplasm of different cell types. Moreover, Amot regulates the AMPK, mTOR, Wnt, and MAPK signaling pathways. However, it is unclear whether Amot is an oncogene or a tumor suppressor gene in different cellular processes. This review focuses on the multifunctional roles of Amot in cancers.




Two Olfactory Pathways to Detect Aldehydes on Locust Mouthpart

2017

Sensing chemical cues is crucial for insects through their olfactory systems to adapt the environments. The receptors employed in insect olfactory system belong to the Odorant Receptor (ORs) and Ionotropic Receptor (IRs) families. In general, ORs and IRs are present in distinct olfactory sensory neurons and function independently. Here, we present evidence that in locust, the abundant host plant odor Hexanal is detected by both IR- and OR-expressing neurons. Use of the palp opening response (POR) as a simple behavioral paradigm in conjunction with RNA interference (RNAi) revealed that these two pathways are both needed for the detection of Hexanal. Two-color fluorescence in situ hybridization showed that OR2 and odorant-binding protein 1 (obp1) were co-localized in palps sensilla basiconica. Obp2a and IR8a were co-localized as well, but associated with sensilla chaetica on the palps. Furthermore, both OR2- and obp1-knockdowns showed reduced POR responses to Hexanal and E-2-Hexenal, and the same was true for Hexanal with IR8a- and obp2a-knockdowns. Detection to E-2-Hexenal was independent of IR8a-mediated gene silencing. Besides, Hexanal and E-2-Hexenal evoked dose-dependent responses in palp basiconica via extracellular recordings. Our results indicate that both OR and IR pathways are involved in the detection of one aldehyde.




Oncogenic Protein Kinase D3 Regulating Networks in Invasive Breast Cancer

2017

Protein Kinase D3 (PRKD3) functions as an important oncogenic driver in invasive breast cancer, which is the leading cause of women mortality. However, PRKD3 regulating network is largely unknown. In this study, we systematically explored PRKD3 regulating networks via investigating phosphoproteome, interactome and transcriptome to uncover the molecular mechanism of PRKD3 in invasive breast cancer. Using iTRAQ, 270 proteins were identified as PRKD3 regulated phosphoproteins from 4619 phosphosites matching 3666 phosphopeptides from 2016 phosphoproteins with p-value <0.005. Transcriptome analysis using affymetrix microarray identified 45 PRKD3 regulated genes, in which 20 genes were upregulated and 25 genes were downregulated with p-value <0.005 upon silencing PRKD3. Using Co-IP in combination of MS identification, 606 proteins were identified to be PRKD3 interacting proteins from 2659 peptides. Further network analysis of PRKD3 regulated phosphoproteins, interacting proteins and regulated genes, reveals 19 hub nodes, including ELAVL1, UBC and BRCA1. UBC was recognized as the most common hub node in PRKD3 regulating networks. The enriched pathway analysis reveals that PRKD3 regulates pathways contributing to multiple cancer related events, including cell cycle, migration and others. Enrichment of cell cycle and cell mobility related pathways across PRKD3 networks, explained the observations that depletion of oncogenic PRKD3 led to alternation of cell cycle and decrease of cell migration ability. Taken together, our current study provided valuable information on the roles as well as the molecular mechanisms of PRKD3 in invasive breast cancer.




Genome-wide Identification and Expression Analysis of Amino Acid Transporters in the Whitefly, Bemisia tabaci (Gennadius)

2017

The whitefly (Bemisia tabaci) is a cosmopolitan and devastating pest of agricultural crops and ornamentals. B. tabaci causes extensive damage by feeding on phloem and by transmitting plant viruses. Like many other organisms, insects depend on amino acid transporters (AATs) to transport amino acids into and out of its cells. We present a genome-wide and transcriptome-wide investigation of the following two families of AATs in B. tabaci biotype B: amino acid/auxin permease (AAAP) and amino acid/polyamine/organocation (APC). A total of 14 putative APCs and 25 putative AAAPs were identified, and a 10-paralog B. tabaci-specific expansion of AAAPs was found by maximum likelihood phylogeny. Detailed gene structure information revealed that 9 members of the B. tabaci-specific AAAP family expansion closely situated on a same scaffold. Expression profiling of the B. tabaci B APC and AAAP genes as affected by stage and plant host showed diverse expression patterns. The analysis of evolutionary rates indicated that purifying selection can explain the B. tabaci-specific AAAP expansion. RNA interference (RNAi)-mediated suppression of two AAAP genes (BtAAAP15 and BtAAAP21) significantly increased the mortality of B. tabaci B adults. The results provide a foundation for future functional analysis of APC and AAAP genes in B. tabaci.




Exosomes from Melatonin Treated Hepatocellularcarcinoma Cells Alter the Immunosupression Status through STAT3 Pathway in Macrophages

2017

Immunosuppression is a significant factor in the progression of tumor invasion and metastasis. Melatonin, a well-known hormone, has certain cytotoxic and immune regulatory effects to inhibit tumor function. Exosomes are small membrane vesicles released by many kinds of cells, which contain different macromolecules, such as mRNAs and microRNAs (miRNAs), and proteins that can mediate communications between cells. Tumor-derived exosomes may cause immunosuppression, however, it is unknown whether melatonin can attenuate an immunosuppressive status by altering the function of tumor-derived exosomes. In the present study, we evaluated the effects of hepatocellularcarcinoma-derived exosomes (Exo-con) and exosomes derived from hepatocellularcarcinoma cells treated with 0.1 mM melatonin (Exo-MT), on the expression of inflammatory factors and programmed death ligand 1(PD-L1) by co-culturing Exo-con and Exo-MT, respectively, with macrophages differentiated from THP-1 cells or RAW264.7 cells. Our in vitro results indicate that Exo-MT can downregulate the expression of PD-L1 on macrophages while Exo-con can upregulate the expression of PD-L1 through flow cytometry and immunofluorescence analysis. In addition, Exo-con upregulates the secretion of cytokines, such as IL-6, IL-10, IL-1β, and TNF-α in macrophages. Accordingly, Exo-MT could attenuate the high expression of these inflammatory cytokines. Furthermore, in vivo experiments confirmed the results found in vitro. PD-L1 expression and cytokine secretion were lower in the Exo-MT group compared with those in the Exo-con group. Working to identify a specific mechanism, our research shows that Exo-MT decreases STAT3 activation compared to the Exo-con group. In summary, we found exosomes from melatonin treated hepatocellularcarcinoma cells alters the immunosupression status through STAT3 pathway in macrophages. Our study may provide a new avenue to investigate the mechanisms of melatonin in regulating an immunosuppressive status.




Mechanism of ribosome translation through mRNA secondary structures

2017

A ribosome is a macromolecular machine that is responsible for translating the genetic codes in messenger RNA (mRNA) into polypeptide chains. It has been determined that besides translating through the single-stranded region, the ribosome can also translate through the duplex region of mRNA by unwinding the duplex. To understand the mechanism of ribosome translation through the duplex, several models have been proposed to study the dynamics of mRNA unwinding. Here, we present a comprehensive review of these models and also discuss other possible models. We evaluate each model and discuss the consistency and/or inconsistency between the theoretical results that are obtained based on each model and the available experimental data, thus determining which model is the most reasonable one to describe the mRNA unwinding mechanism and dynamics of the ribosome. Moreover, a framework for future studies in this subject is provided.




Eupafolin Exhibits Potent Anti-Angiogenic and Antitumor Activity in Hepatocellular Carcinoma

2017

Eupafolin is a flavonoid extracted from the common sage herb which has been used in China as traditional medicine. Previous studies had reported that eupafolin had antioxidative, anti-inflammatory and antitumor effects. However, the function and the mechanism of eupafolin to exert its antitumor activity, especially its effect on tumor angiogenesis, have not been elucidated. Herein, we showed that eupafolin significantly inhibited vascular endothelial growth factor (VEGF)-induced cell proliferation, migration and tube formation of human umbilical vascular endothelial cells (HUVECs) in a dose-dependent manner. Meanwhile, the new blood microvessels induced by VEGF in the matrigel plug were also substantially suppressed by eupafolin. The results of HCC xenograft experiments demonstrated eupafolin remarkably inhibited tumor growth and tumor angiogenesis in vivo, suggesting the antitumor activity exerted by eupafolin was closely correlated with its potency on tumor angiogenesis. Mechanism investigations revealed that eupafolin significantly blocked VEGF-induced activation of VEGFR2 in HUVEC cells as well as its downstream signaling pathway. In addition to the effect on endothelial cells, through inhibiting Akt activity in tumor cells, VEGF secretion in HepG2 was dramatically decreased after eupafolin treatment. Our study was the first to report the activity of eupafolin against tumor angiogenesis as well as the underlying mechanism by which eupafolin to exert its anti-angiogenic activity.




MicroRNA-142-3p and let-7g Negatively Regulates Augmented IL-6 Production in Neonatal Polymorphonuclear Leukocytes

2017

Neonatal PMN are qualitatively impaired in functions, yet they frequently reveal augmented inflammatory reactions during sepsis. Here, we hypothesized that PMN from newborns produce more IL-6 than those from adults under LPS stimulation, in which transcriptional or posttranscriptional regulation is involved in the altered expression. We found that neonatal PMN produced significantly higher IL-6 mRNA and protein than adult PMN. The higher IL-6 expression was not related to transcriptional but posttranscriptional regulation as the IL-6 expression was affected by the addition of cycloheximide but not actinomycin. To examine whether miRNA was involved in the IL-6 regulation of neonatal PMN, we surveyed differential displays of miRNAs that could potentially regulate IL-6 expression before and after LPS stimulation. Four miRNAs: hsa-miR-26a, hsa-miR-26b, hsa-miR-142-3p and hsa-let 7g decreased or increased after LPS treatment for 4 h. Further validation by qRT-PCR identified miR-26b, miR-142-3p and let-7g significantly changed in neonatal PMN after LPS stimulation. The functional verification by transfection of miR-142-3p and let-7g precursors into neonatal PMN significantly repressed the IL-6 mRNA and protein expression, suggesting that miR-142-3p and let-7g negatively regulate IL-6 expression in neonatal PMN. Modulation of miRNA expression may be used to regulate IL-6 production in newborns with altered inflammatory reactions.




Sleep Duration and Patterns in Chinese Older Adults: a Comprehensive Meta-analysis

2017

This meta-analysis examined the mean sleep duration and patterns in Chinese older adult population. A literature search was systematically conducted covering major English (PubMed, Embase and PsycINFO) and Chinese (Chinese National Knowledge Infrastructure (CNKI), WanFang and SinoMed) databases. Data in studies with the mean and standard deviation of sleep duration and/or the proportion of short and long sleep durations in Chinese older adults were extracted and pooled using random-effects models. Subgroup analyses were conducted according to gender, region, area, survey time and sample size. A total of 36 studies with 150,616 subjects were included for analyses. The pooled mean sleep duration of 21 studies with available data was 6.82 hours/day (95% CI: 6.59-7.05 hours/day). The estimated proportions of sleep duration <5 hours/day, <6 hours/day, <7 hours/day were 18.8% (95% CI: 1.7%-35.9%), 26.7% (95% CI: 19.7%-33.7%) and 42.3% (95% CI: 34.8%-49.8%), respectively. The pooled proportions for long sleepers were 22.6% (95% CI: 13.9%-31.4%) (>8 hours/day) and 17.6% (95% CI: 12.4%-22.9%) (>9 hours/day). Given the adverse effects of unhealthy sleep patterns, health professionals should pay more attention to sleep patterns in this population in China.




PPARD is an Inhibitor of Cartilage Growth in External Ears

2017

Peroxisome proliferator-activated receptor beta/delta (PPARD) is an important determinant of multiple biological processes. Our previous studies identified a missense mutation in the PPARD gene that significantly reduces its transcription activity, and consequently causes enlarged external ears in pigs. However, the mechanisms underlying the causality has remained largely unknown. Here, we show that PPARD retards the development of auricular cartilage by accelerating the apoptosis of cartilage stem/progenitor cells (CSPCs), the terminal differentiation of cartilage cells and the degradation of cartilage extracellular matrix in the auricle. At the transcription level, PPARD upregulates a set of genes that are associated with CSPCs apoptosis and chondrogenic differentiation, chondroblast differentiation and extracellular matrix degradation. ChIP-seq identified direct target genes of PPARD, including a well-documented gene for cartilage development: PPARG. We further show that compared to wild-type PPARD, the G32E mutant up-regulates the expression of PPARG and subsequently leads to the downregulation of critical genes that inhibit cartilage growth. These findings allow us to conclude that PPARD is an inhibitor of auricular cartilage growth in pigs. The causative mutation (G32E) in the PPARD gene attenuates the PPARD-mediated retardation of cartilage growth in the auricle, contributing to enlarged ears in pigs. The findings advance our understanding of the mechanisms underlying auricular development in mammals, and shed insight into the studies of innate pinna disorders and cartilage regeneration medicine in humans.




Andrographolide Inhibits Angiogenesis by Inhibiting the Mir-21-5p/TIMP3 Signaling Pathway

2017

Angiogenesis provides nutrients and oxygen to promote tumor growth and affords a channel that facilitates tumor cell entry into the circulation. Andrographolide (Andro) possess anti-tumor activity; however, its direct effect on angiogenesis still needs to be clarified. In this study, our experiments revealed that Andro significantly inhibited vascular growth in chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) models. Meanwhile, tumor angiogenesis was also suppressed by Andro. Additionally, we found that cell proliferation, migration and tube formation of vascular endothelial cells was inhibited by Andro treatment in vitro. The effect was primarily mediated through inhibition of miR-21-5p expression and further targeting of TIMP3. This work provides evidence that Andro directly inhibits angiogenesis and might be an effective anti-angiogenic therapeutic drug for cancer treatment.




Ezh2 Acts as a Tumor Suppressor in Kras-driven Lung Adenocarcinoma

2017

Previous studies have suggested that enhancer zeste homolog 2 (Ezh2), a histone methyltransferase subunit of polycomb repressive complex 2 (PRC2), acts as an oncogene in lung adenocarcinoma (ADC) development. However, we found that in human lung ADC samples, deletion and mutations of EZH2 were also frequently present, with 14% of patients harboring loss-of-function EZH2 alterations. To explore the effect of Ezh2 loss on lung tumor formation, lung epithelial Ezh2 gene was deleted in Kras-driven lung ADC mouse model. Unexpectedly, Ezh2 loss dramatically promoted Kras-driven ADC formation. KrasG12D/+;Ezh2fl/fl mice exhibited shorter lifespan, more tumor lesions and higher tumor burden than KrasG12D/+ mice, suggesting the tumor-suppressive role of Ezh2 in Kras-driven ADCs. Mechanistically, Ezh2 loss amplified Akt and ERK activation through de-repressing its target insulin-like growth factor 1 (Igf1). Additionally, Ezh2 loss cooperated with Kras mutation to exacerbate the inflammatory response, as shown by massive macrophage and neutrophil infiltrates, as well as a marked increase in tumor-associated cytokines such as IL-6 and TNF-α. Taken together, our findings revealed the tumor suppressive function of Ezh2 in Kras-driven ADCs, underlining the importance of revaluating the application of EZH2 inhibitors in a variety of cancers.




Dual Delivery of NGF and bFGF Coacervater Ameliorates Diabetic Peripheral Neuropathy via Inhibiting Schwann Cells Apoptosis

2017

Diabetic neuropathy is a kind of insidious complications that impairs neural and vascular function and ultimately leads to somatic and visceral denervation. Basic fibroblast growth factor (bFGF) and nerve growth factor (NGF) are important neurotrophic factors for stimulating angiogenesis and improving peripheral nerve function. Administrating a single factor has good therapeutic effect on diabetic peripheral neuropathy (DPN). However, the short half-life and rapid diffusion of growth factors under physiological conditions limits its clinical applications. Here, we used a biodegradable coacervate, composed of heparin and polycation, to dominate the combined release of bFGF and NGF in a steady fashion. We found this combined growth factors (GFs) coacervate, administered as a single injection, improved motor and sensory functions, restored morphometric structure and decreased apoptosis of Schwann cells in a rat model of prolonged DPN. Similarly the GFs coacervate, as compared with free bFGF and NGF combination, markedly reduced the apoptosis level of a rat Schwann cell line, RSC 96 cells in vitro. We also demonstrated that neuroprotective effects of the GFs coacervate in both rat DPN model and hyperglycemia-induced RSC 96 cell model is likely due to suppression of endocytoplasmic reticulum stress (ERS).




The Myosin II Inhibitor, Blebbistatin, Ameliorates FeCl3-induced Arterial Thrombosis via the GSK3β-NF-κB Pathway

2017

Arterial thrombosis and its related diseases are major healthcare problems worldwide. Blebbistatin is an inhibitor of myosin II, which plays an important role in thrombosis. The aim of our study is to explore the effect and potential mechanism of blebbistatin on arterial thrombosis. A ferric chloride (FeCl3) solution at a concentration of 5% was used to induce carotid artery thrombosis in mice. Immunohistochemistry and immunofluorescence staining were used to detect the expression or activation of non-muscle myosin heavy chain IIA (NMMHC IIA), tissue factor (TF), GSK3β and NF-κB. Blebbistatin (1 mg/kg, i.p.) significantly reduced carotid artery thrombosis induced by FeCl3 solution in mice, inhibited NMMHC IIA expression and impeded TF expression via the GSK3β-NF-κB signalling pathway in mouse arterial vascular tissues. The present study demonstrates that blebbistatin may impede TF expression partly via the Akt/GSK3β-NF-κB signalling pathways in the endothelium in a FeCl3 model, shedding new insights into the pathogenesis of arterial thrombosis and providing new clues for the development of antithrombotic drugs.




Complex Relationship between Obesity and the Fat Mass and Obesity Locus

2017

In the 21st century, obesity has become a serious problem because of increasing obese patients and numerous metabolic complications. The primary reasons for this situation are environmental and genetic factors. In 2007, FTO (fat mass and obesity associated) was the first gene identified through a genome-wide association study (GWAS) associated with obesity in humans. Subsequently, a cluster of single nucleotide polymorphisms (SNPs) in the first intron of the FTO gene was discovered to be associated with BMI and body composition. Various studies have explored the mechanistic basis behind this association. Thus, emerging evidence showed that FTO plays a key role regulating adipose tissue development and functions in body size and composition. Recent prevalent research topic concentrated in the three neighboring genes of FTO: RPGRIP1L, IRX3 and IRX5, as having a functional link between obesity-associated common variants within FTO and the observed human phenotypes. The purpose of this review is to present a comprehensive picture of the impact of FTO on obesity susceptibility and to illuminate these new studies of FTO function in adipose tissue.




SDF-1 in Mammary Fibroblasts of Bovine with Mastitis Induces EMT and Inflammatory Response of Epithelial Cells

2017

Fibroblasts constitute the majority of the stromal cells within bovine mammary gland, yet the functional contributions of these cells to mastitis and fibrosis and the mechanism are poorly understood. In this study, we demonstrate that inflammation-associated fibroblasts (INFs) extracted from bovine mammary glands with clinical mastitis had different expression pattern regarding to several extracellular matrix (ECM) proteins, chemokines and cytokines compared to normal fibroblasts (NFs) from dairy cows during lactation. The INFs induced epithelial-mesenchymal transition (EMT) and inflammatory responses of mammary epithelial cells in a vitro co-culture model. These functional contributions of INFs to normal epithelial cells were mediated through their ability to secrete stromal cell-derived factor 1 (SDF-1). SDF-1 was highly secreted/expressed by INFs, lipopolysaccharide (LPS) -treated NFs, lipoteichoic acid (LTA) -treated NFs, as well as mastitic tissue compared to their counterparts. Exogenous SDF-1 promoted EMT on epithelial cells through activating NF-κB pathway, induced inflammation response and inhibited proliferation of epithelial cells. In addition, SDF-1 was able to induce mastitis and slight fibrosis of mouse mammary gland, which was attenuated by a specific inhibitor of the receptor of SDF-1. Our findings indicate that stromal fibroblasts within mammary glands with mastitis contribute to EMT and inflammatory responses of epithelial cells through the secretion of SDF-1, which could result in the inflammation spread and fibrosis within mammary gland.




Recapitulating and Correcting Marfan Syndrome in a Cellular Model

2017

Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in FBN1 gene, which encodes a key extracellular matrix protein FIBRILLIN-1. The haplosufficiency of FBN1 has been implicated in pathogenesis of MFS with manifestations primarily in cardiovascular, muscular, and ocular tissues. Due to limitations in animal models to study the late-onset diseases, human pluripotent stem cells (PSCs) offer a homogeneic tool for dissection of cellular and molecular pathogenic mechanism for MFS in vitro. Here, we first derived induced PSCs (iPSCs) from a MFS patient with a FBN1 mutation and corrected the mutation, thereby generating an isogenic “gain-of-function” control cells for the parental MFS iPSCs. Reversely, we knocked out FBN1 in both alleles in a wild-type (WT) human embryonic stem cell (ESC) line, which served as a loss-of-function model for MFS with the WT cells as an isogenic control. Mesenchymal stem cells derived from both FBN1-mutant iPSCs and -ESCs demonstrated reduced osteogenic differentiation and microfibril formation. We further demonstrated that vascular smooth muscle cells derived from FBN1-mutant iPSCs showed less sensitivity to carbachol as demonstrated by contractility and Ca2+ influx assay, compared to the isogenic controls cells. These findings were further supported by transcriptomic anaylsis of the cells. Therefore, this study based on both gain- and loss-of-function approaches confirmed the pathogenetic role of FBN1 mutations in these MFS-related phenotypic changes.




Aldehyde Dehydrogenases 1A2 Expression and Distribution are Potentially Associated with Neuron Death in Spinal Cord of Tg(SOD1*G93A)1Gur Mice

2017

The pathogenesis of amyotrophic lateral sclerosis (ALS) has not been unclear yet, it might be associated with the abnormal expression and distribution of certain proteins. Aldehyde dehydrogenases 1A2 (ALDH1A2) was thought to be one of potential candidates. Therefore, in this study we observed and analyzed the alteration of the expression and distribution of ALDH1A2 in the spinal cord of wild-type (WT) and Tg(SOD1*G93A)1Gur mice. We compared the expression and distribution of ALDH1A2 in the different segments, anatomic regions and neural cells of spinal cord at the different stages of WT and Tg(SOD1*G93A)1Gur mice applied the methods of fluorescent immunohistochemistry and western blot. Results revealed that ALDH1A2 extensively expressed and distributed in the spinal cord of adult WT and Tg(SOD1*G93A)1Gur mice. The expression and distribution of ALDH1A2 in the white matter including the anterior, posterior and lateral funiculus were more than that in the gray matter including the central canal, the anterior and dorsal horn. ALDH1A2 majorly expressed and distributed in the astrocyte, microglial, oligodendrocyte and neuron cells. The ALDH1A2 expression significantly decreased and redistributed in some anatomic regions of spinal cord at the onset and progression stages of Tg(SOD1*G93A)1Gur mice. The expression decrease of ALDH1A2 followed with the increase of neuron cells death. This study suggested that the alteration of expression and distribution of ALDH1A2 was potentially associated with the pathogenesis of ALS.




DNA Methylation Mediated Down-Regulation of miR-370 Regulates Cell Growth through Activation of the Wnt/β-Catenin Signaling Pathway in Human Osteosarcoma Cells

2017

MicroRNA-370 (miR-370) has been observed to act as a tumor suppressor through the targeting of different proteins in a variety of tumors. Our previous study indicated that miR-370 was able to target forkhead box protein M1 (FOXM1) to inhibit cell growth and metastasis in human osteosarcoma cells. In this study, we reported that FOXM1 interacted with β-catenin in vitro and in vivo. Similar to FOXM1, critical components of the Wnt signaling pathway, including β-catenin, c-Myc, and Cyclin D1, were also highly expressed in different human osteosarcoma cells lines. Pharmacological inhibition of FOXM1 or β-catenin but not of c-Myc was associated with the increased expression of miR-370. Ectopic expression of miR-370 inhibited the downstream signaling of β-catenin. Moreover, osteosarcoma cells treated with 5-AZA-2'-deoxycytidine (AZA), a DNA methylation inhibitor, exhibited increased levels of miR-370 and decreased levels of β-catenin downstream targets, which resulted in inhibition of cell proliferation and colony formation ability. In conclusion, our results supported a model in which the DNA methylation-mediated down-regulation of miR-370 reduced its inhibitory effect on FOXM1, thereby promoting FOXM1-β-catenin interaction and activating the Wnt/β-Catenin signaling pathway in human osteosarcoma cells.




Multifaceted Regulation of Gene Expression by the Apoptosis- and Splicing-Associated Protein Complex and Its Components

2017

The differential deposition of RNA-binding proteins (RBPs) on pre-mRNA mediates the processes of gene expression. One of the complexes containing RBPs that play a crucial part in RNA metabolism is the apoptosis-and splicing-associated protein (ASAP) complex. In this review, we present a summary of the structure of ASAP complex and its localization. Also, we discuss the findings by different groups on various functions of the subunits of the ASAP complex in RNA metabolism. The subunits of the ASAP complex are RNPS1, Acinus and SAP18. Originally, the ASAP complex was thought to link RNA processing with apoptosis. Further studies have shown the role of these components in RNA metabolism of cells, including transcription, splicing, translation and nonsense-mediated mRNA decay (NMD). In transcription, RNPS1 is involved in preventing the formation of R-loop, while Acinus and SAP18 suppress transcription with the help of histone deacetylase. On the one hand, individual components of the ASAP complex, namely RNPS1 and Acinus act as splicing activators, whereas on the other hand, in-vitro assay shows that the ASAP complex behaves as splicing repressor. In addition, the individual members of the ASAP complex associates with the exon junction complex (EJC) to play roles in splicing and translation. RNPS1 increases the translation efficiency by participating in the 3'end processing and polysome association of mRNAs. Similarly, during NMD RNPS1 aids in the recruitment of decay factors by interacting with EJC.




Increased expression of thyroid hormone responsive protein (THRSP) is the result but not the cause of higher intramuscular fat content in cattle

2017

Thyroid hormone responsive protein (THRSP) is known to be involved in lipogenic processes in rodents. In cattle, THRSP could be a potential molecular marker for intramuscular fat (IMF) deposition since mRNA abundance was frequently found to be increased in skeletal muscle with high IMF content compared to those with low IMF. The aim of this study was to elucidate the background of this differential expression and to evaluate the role of THRSP as candidate for increased IMF content in cattle. By combination of mRNA and protein analyses, we could demonstrate that THRSP is present mainly in nuclei of adipose tissue, in intramuscular fat cells and associated cells, and in cells of the portal triad of liver, whereas muscle cells did not express THRSP. Cell culture analyses revealed furthermore that THRSP is expressed in mature adipocytes rather than in early stages of adipogenesis. Collectively, our data support the putative role of THRSP as transcriptional regulator and demonstrate that an increased expression of THRSP in M. longissimus is a consequence of but not the reason for a higher number of intramuscular adipocytes in cattle with enhanced IMF deposition.




Cold Inducible RNA Binding Protein Is Involved in Chronic Hypoxia Induced Neuron Apoptosis by Down-Regulating HIF-1α Expression and Regulated By microRNA-23a

2017

Background: Neuron apoptosis mediated by hypoxia inducible factor 1α (HIF-1α) in hippocampus is one of the most important factors accounting for the chronic hypobaric hypoxia induced cognitive impairment. As a neuroprotective molecule that is up-regulated in response to various environmental stress, CIRBP was reported to crosstalk with HIF-1α under cellular stress. However, its function under chronic hypobaric hypoxia remains unknown.Objective: In this study, we tried to identify the role of CIRBP in HIF-1α mediated neuron apoptosis under chronic hypobaric hypoxia and find a possible method to maintain its potential neuroprotective in long-term high altitude environmental exposure.Methods: We established a chronic hypobaric hypoxia rat model as well as a tissue culture model where SH-SY5Y cells were exposed to 1% hypoxia. Based on these models, we measured the expressions of HIF-1α and CIRBP under hypoxia exposure and examined the apoptosis of neurons by TUNEL immunofluorescence staining and western blot analysis of apoptosis related proteins. In addition, by establishing HIF-1α shRNA and pEGFP-CIRBP plasmid transfected cells, we confirmed the role of HIF-1α in chronic hypoxia induced neuron apoptosis and identified the influence of CIRBP over-expression upon HIF-1α and neuron apoptosis in the process of exposure. Furthermore, we measured the expression of the reported hypoxia related miRNAs in both models and the influence of miRNAs' over-expression/knock-down upon CIRBP in the process of HIF-1α mediated neuron apoptosis.Results: HIF-1α expression as well as neuron apoptosis was significantly elevated by chronic hypobaric hypoxia both in vivo and in vitro. CIRBP was induced in the early stage of exposure (3d/7d); however as the exposure was prolonged (21d), CIRBP level of the hypoxia group became significantly lower than that of control. In addition, HIF-1α knockdown significantly decreased neuron apoptosis under hypoxia, suggesting HIF-1α may be pro-apoptotic in the process of exposure. CIRBP over-expression significantly suppressed HIF-1α up-regulation in hypoxia and inhibited HIF-1α mediated neuron apoptosis. Interestingly, miR-23a was also induced by hypoxia exposure and showed the same changing tendency with CIRBP (increasing in 3d/7d, decreasing in 21d). In addition, over-expressing miR-23a up-regulated CIRBP, down-regulated HIF-1α [...]



Targeting HSP90-HDAC6 Regulating Network Implicates Precision Treatment of Breast Cancer

2017

Breast cancer is the leading cause of women death. Heat shock protein 90 (HSP90) and Histone deacetylase 6 (HDAC6) are promising anti-cancer drug targets. However, it's still unclear the applicability of anti-HSP90 and anti-HDAC6 strategies in precision treatment of breast cancer. In current study, we found that triple negative breast cancer (TNBC) cells, compared to T47D, an ERα+ breast cancer cell line, exhibited 7~40 times lower IC50 values, stronger cell cycle perturbation, increased cell apoptosis and stronger inhibition of cell migration upon 17-DMAG treatment, while T47D, compared to TNBC cells, expressed higher HDAC6 and showed stronger anti-cancer response upon treatment of Tubacin. Mechanically, 17-DMAG treatment inhibited a complex network consists at least ERK, AKT, and Hippo pathway in TNBC cells, and higher expression of HDAC6 inhibited HSP90 activity via deacetylating HSP90. Furthermore, we found higher HDAC6 expression level in tamoxifen-resistance T47D than that in T47D, and Tubacin treatment suppressed the growth of tamoxifen-resistant cells in vivo. Our data suggested that anti-HSP90 and anti-HDAC6 are promising strategies to treat TNBC and ERα+ breast cancers respectively, and anti-HDAC6 can be considered during treatment of tamoxifen-resistance breast cancers.




Deguelin Attenuates Allergic Airway Inflammation via Inhibition of NF-κb Pathway in Mice

2017

Asthma is a chronic respiratory disease characterized by airway inflammation and remodeling, resulting in a substantial economic burden on both patients and society. Deguelin, a constituent of the Leguminosae family, exhibits anti-proliferative and anti-inflammatory activities in cancer mice models via inhibiting phosphatidylinositol 3-kinases and the NF-κB pathway. We demonstrated that deguelin effectively reduced OVA-induced inflammatory cell recruitment, decreased lung tissue inflammation and mucus production, suppressed airway hyperresponsiveness, and inhibited serum immunoglobulin and Th2 cytokine levels in a dose-dependent manner in asthmatic mice. In addition, we found that deguelin reduced inflammatory gene expressions both in vivo and in vitro, which were closely associated with activation of the NF-κB signaling pathway. Thus, we further explored the underlying mechanisms of deguelin in normal human bronchial epithelial cells (BEAS-2B). Our results suggested that deguelin inhibited NF-κB binding activity by enhancing the ability of IκBα to maintain NF-κB in an inactive form in the cytoplasm and preventing the TNF-α induced translocation of p65 to the nucleus. In conclusion, our research indicates that deguelin attenuates allergic airway inflammation via inhibition of NF-κB pathway in mice model and may act as a potential therapeutic agent for patients with allergic airway inflammation.




Ethyl acetate fraction of Huogu formula inhibits adipogenic differentiation of bone marrow stromal cells via the BMP and Wnt signaling pathways

2017

Elevated adipogenesis of bone marrow stromal cells (BMSCs) is closely associated with non-traumatic osteonecrosis of femoral head (ONFH). Our previous studies have shown that Huogu (HG) formula was effective both in clinic experience and experimental ONFH. How HG impacts the differentiation of BMSCs and what is the underlying molecular mechanism remain largely unknown. Our results showed that ethyl acetate extract of HG (HGE) significantly decreased the adipocyte differentiation as determined by oil red staining, while slightly increased the ALP activity. Investigation of the molecular mechanism revealed that HGE could inhibit the mRNA and protein expression of peroxisome proliferators-activated receptor (PPAR)γ, lipoprotein lipase (LPL) and adipocyteprotein2 (AP2). Interestingly, the inhibition of adipogenic differentiation in BMSCs by HGE could be restored by DKK-1, an inhibitor of Wnts. However, Noggin (an inhibitor of BMPs) displayed an additive role with HGE in suppressing the expression of PPARγ, LPL, and AP2. Furthermore, the bone marrow fat formation, as well as the expression of Wnt3a and PPARγ, was effectively regulated by HGE in the steroid-induced ONFH rats. Our results demonstrated that HGE treatment significantly inhibited adipogenesis and slightly promoted osteogenesis of BMSCs through regulating the BMP and Wnt pathways. The findings shed lights on the molecular mechanism of HGE in the inhibition of adipogenesis and provide scientific rationale for its clinical application of HGE in the treatment of ONFH.




Dipalmitoylphosphatidic acid inhibits tumor growth in triple-negative breast cancer

2017

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with a poor prognosis, accounting for approximately 12-24% of breast cancer cases. Accumulating evidence has indicated that there is no effective targeted therapy available for TNBC. Dipalmitoylphosphatidic acid (DPPA) is a bioactive phospholipid. However, the function of DPPA in the growth of TNBC has not yet been studied. In this study, we employed TNBC cells and a subcutaneous tumor model to elucidate the possible effect of DPPA on tumor growth in TNBC. We showed that DPPA significantly inhibited tumor growth in the mouse subcutaneous tumor model and suppressed cell proliferation and angiogenesis in TNBC tumor tissues. This inhibition was mediated partly by suppressing the expression of cyclin B1 (CCNB1), which directly promoted the accumulation of cells in the G2 phase and arrested cell cycle progression in human TNBC. In addition, the inhibition of tumor growth by DPPA may also be mediated by the suppression of tumor angiogenesis in TNBC. This work provides initial evidence that DPPA might be vital as an anti-tumor drug to treat TNBC.




Characterization of Cytosine Methylation and the DNA Methyltransferases of Toxoplasma gondii

2017

DNA methylation is a key epigenetic modification which confers phenotypic plasticity and adaptation. Cyst-forming strains of Toxoplasma gondii undergo tachyzoite to bradyzoite conversion after initial acute infection of a host, and the reverse conversion may occur in immune-suppressed hosts. The formation of m5C is catalyzed by DNA methyltransferase (DNMT). We identified two functional DNA methyltransferases, TgDNMTa and TgDNMTb, in T. gondii that may mediate DNA methylation. The recombinant proteins showed intrinsic methyltransferase activity; both have higher transcription levels in bradyzoites than that in tachyzoites. We performed genome-wide analysis of DNA methylation in tachyzoites and bradyzoites. The results showed more methylation sites in bradyzoites than that in tachyzoites. The most significantly enriched GO-terms of genes with DNA methylation were associated with basal cellular processes such as energy metabolism and parasite resistance to host immunity. Tachyzoite proliferation in parasitophorous vacuoles (PV) can be inhibited by the DNA methyltransferase inhibitor 5-azacytidine, a chemical analogue of the nucleotide cytosine that can inactivate DNA methyltransferases. These findings provide the first confirmation of DNA methylation in T. gondii.




The role of germ cell loss during primordial follicle assembly: a review of current advances

2017

In most female mammals, early germline development begins with the appearance of primordial germ cells (PGCs), and develops to form mature oocytes following several vital processes. It remains well accepted that significant germ cell apoptosis and oocyte loss takes place around the time of birth. The transition of the ovarian environment from fetal to neonatal, coincides with the loss of germ cells and the timing of follicle formation. All told it is common to lose approximately two thirds of germ cells during this transition period. The current consensus is that germ cell loss can be attributed, at least in part, to programmed cell death (PCD). Recently, autophagy has been implicated as playing a part in germ cell loss during the time of parturition. In this review, we discuss the major opinions and mechanisms of mammalian ovarian PCD during the process of germ cell loss. We also pay close attention to the function of autophagy in germ cell loss, and speculate that autophagy may also serve as a critical and necessary process during the establishment of primordial follicle pool.




Estradiol Suppresses TLR4-triggered Apoptosis of Decidual Stromal Cells and Drives an Anti-inflammatory TH2 Shift by Activating SGK1

2017

A pro-inflammatory cytokine profile at the feto-maternal interface may predispose immune maladaptation notably in early miscarriages. We investigated the involvement of estradiol (E2)-activated serum-glucocorticoid regulated kinase 1 (SGK1) in preserving the tolerogenic and pro-survival intrauterine microenvironment beneficial to gestation maintenance. Decidual SGK1 was down-regulated in early miscarriage, consistent with the lower serum E2 concentration seen in pregnancy loss. Lipopolysaccharide (LPS)/Toll-like receptors 4 (TLR4) signaling induced apoptosis and the pro-inflammatory T helper type (TH) 1 response of decidual stromal cells (DSCs) were associated with miscarriage. SGK1 activation was suppressed by LPS/TLR4 signaling and would be rescued by E2 administration via the PI3K signaling pathway in DSCs. SGK1 activation attenuated TLR4-mediated cell apoptosis, while promoting cell viability of DSCs by up-regulating the pro-survival genes BCL2 and XIAP, and enhancing the phosphorylation of FOXO1. Furthermore, E2-induced SGK1 activation reduced the secretion of pro-inflammatory TH1 cytokines, and promoted the generation of TH2 cytokines and elevated IRF4 mRNA and protein levels in LPS-incubated DSCs. Pharmacologic inhibition of SGK1 or suppression by small interfering (si) RNA increased the phosphorylation and nuclear translocation of NF-κB to reverse the pro-TH2 and anti-inflammatory effects of E2 pretreatment, leading to compromised pregnancy. These findings suggest that the E2-mediated SGK1 activation suppressed LPS-mediated apoptosis and promoted the anti-inflammatory TH2 responses in DSCs, ultimately contributing to a successful pregnancy.




Role of Epigenetics in Uveal Melanoma

2017

Uveal melanoma (UM) is a severe human malignancy with a high mortality rate that demands continued research into new and alternative forms of prevention and treatment. The emerging field of epigenetics is beginning to unfold an era of contemporary approaches to reducing the risk and improving the clinical treatment of UM. Epigenetic changes have a high prevalence rate in cancer, are reversible in nature, and can lead to cancer characteristics even in mutation-free cells. The information contained in this review highlights and expands on the main mechanisms of epigenetic dysregulation in UM tumorigenesis, progression and metastasis, including microRNA expression, hypermethylation of genes and histone modification. Epigenetic drugs have been shown to enhance tumor suppressor gene expression and drug sensitivity in many other cancer cell lines and animal models. An increased understanding of epigenetic mechanisms in UM will be invaluable in the design of more potent epigenetic drugs, which when used in combination with traditional therapies, may permit improved therapeutic outcomes.




MiR-696 Regulates C2C12 Cell Proliferation and Differentiation by Targeting CNTFRα

2017

Micro-696 (miR-696) has been previously known as an exercise related miRNA, which has a profound role in fatty acid oxidation and mitochondrial biogenesis of skeletal muscle. However, its role in skeletal myoblast proliferation and differentiation is still unclear. In this study, we found that miR-696 expressed highly in skeletal muscle and reduced during C2C12 myoblasts differentiation. MiR-696 overexpression repressed C2C12 myoblast proliferation and myofiber formation, while knockdown of endogenous miR-696 expression showed opposite results. During myogenesis, we observed an inversed expression pattern between miR-696 and CNTFRα in vitro, and demonstrated that miR-696 could specifically target CNTFRα and repress the expression of CNTFRα. Additionally, we further found that knockdown of CNTFRα suppressed the proliferation and differentiation of C2C12 cells. Taking all things together, we propose a novel insight that miR-696 down-regulates C2C12 cell myogenesis by inhibiting CNTFRα expression.




Photoacoustic-Based Multimodal Nanoprobes: from Constructing to Biological Applications

2017

Multimodal nanoprobes have attracted intensive attentions since they can integrate various imaging modalities to obtain complementary merits of single modality. Meanwhile, recent interest in laser-induced photoacoustic imaging is rapidly growing due to its unique advantages in visualizing tissue structure and function with high spatial resolution and satisfactory imaging depth. In this review, we summarize multimodal nanoprobes involving photoacoustic imaging. In particular, we focus on the method to construct multimodal nanoprobes. We have divided the synthetic methods into two types. First, we call it “one for all” concept, which involves intrinsic properties of the element in a single particle. Second, “all in one” concept, which means integrating different functional blocks in one particle. Then, we simply introduce the applications of the multifunctional nanoprobes for in vivo imaging and imaging-guided tumor therapy. At last, we discuss the advantages and disadvantages of the present methods to construct the multimodal nanoprobes and share our viewpoints in this area.




Novel approaches to vitiligo treatment via modulation of mTOR and NF-κB pathways in human skin melanocytes

2017

Vitiligo is a skin depigmentation disorder with an increasing prevalence. Among recognized mechanisms is the oxidative stress that affects melanocytes which are responsible for skin pigmentation. Studies have shown that high concentration of hydrogen peroxide, or H2O2, induces apoptotic activities. Few studies have been done with lower doses of H2O2. Using human skin melanocytes, we investigated the effect of moderate concentration of H2O2 on melanocyte dendrites. Confocal data show that H2O2 at 250 µM induces loss of dendrites, as indicated by cytoskeletal proteins. α-melanocyte stimulating hormone or α-MSH pretreatment protects against H2O2-induced loss of dendrites, while α-MSH alone enhances dendrites. PI3K/AKT inhibitor LY294002 and mTORC1 inhibitor Rapamycin inhibit α-MSH-induced dendrites. In this study, we also investigated the effect of TNFα on cultured human skin melanocytes, since TNFα plays important roles in vitiligo. Confocal data demonstrate that TNFα induces NFκB activation. Western blot analysis shows that TNFα induces IκB phosphorylation and degradation. Interestingly, α-MSH does not have any effect of TNFα-induced IκB degradation and NF-κB activation. α-MSH, however, activates mTORC1 pathway. TNFα induces p38 but not AMPKα activation. Collectively, our data suggest that modulation of mTOR and NF-κB pathways may be a novel approach for better clinical management of vitiligo.




Inhibition of Proteasome Activity Induces Aggregation of IFIT2 in the Centrosome and Enhances IFIT2-Induced Cell Apoptosis

2017

IFN-induced protein with tetratricopeptide repeats 2 (IFIT2), one of the most highly responsive interferon-stimulated genes, inhibits the proliferation and migration of cancer cells and regulates viral replication. IFIT2 has been demonstrated to be a cytoskeleton-associated protein that becomes enriched in the mitotic spindle of cells. However, the molecular mechanisms by which IFIT2 executes biological functions are largely unclear. The findings of this study showed that inhibiting the activation of proteasome led to the enrichment of IFIT2 and induced the aggregation of IFIT2 protein in the centrosome. Microtubule inhibitor colchicine and dynein inhibitor ciliobrevin inhibited the proteasome inhibitor-induced aggregation of IFIT2 protein in the centrosome. Intriguingly, IFIT2 and proteasome inhibitor worked together to induce the apoptosis of cancer cells. The results of the present study revealed that the inhibition of proteasome activity blocked the degradation of IFIT2 and promoted the aggregation of IFIT2 in the centrosome, which in turn induced cell apoptosis. In short, IFIT2 may be a potential target for cancer therapeutics.




Comparative Mitogenomic Analyses of Praying Mantises (Dictyoptera, Mantodea): Origin and Evolution of Unusual Intergenic Gaps

2017

Praying mantises are a diverse group of predatory insects. Although some Mantodea mitogenomes have been reported, a comprehensive comparative and evolutionary genomic study is lacking for this group. In the present study, four new mitogenomes were sequenced, annotated, and compared to the previously published mitogenomes of other Mantodea species. Most Mantodea mitogenomes share a typical set of mitochondrial genes and a putative control region (CR). Additionally, and most intriguingly, another large non-coding region (LNC) was detected between trnM and ND2 in all six Paramantini mitogenomes examined. The main section in this common region of Paramantini may have initially originated from the corresponding control region for each species, whereas sequence differences between the LNCs and CRs and phylogenetic analyses indicate that LNC and CR are largely independently evolving. Namely, the LNC (the duplicated CR) may have subsequently degenerated during evolution. Furthermore, evidence suggests that special intergenic gaps have been introduced in some species through gene rearrangement and duplication. These gaps are actually the original abutting sequences of migrated or duplicated genes. Some gaps (G5 and G6) are homologous to the 5' and 3' surrounding regions of the duplicated gene in the original gene order, and another specific gap (G7) has tandem repeats. We analysed the phylogenetic relationships of fifteen Mantodea species using 37 concatenated mitochondrial genes and detected several synapomorphies unique to species in some clades.




PADI4 Epigenetically Suppresses p21 Transcription and Inhibits Cell Apoptosis in Fibroblast-like Synoviocytes from Rheumatoid Arthritis Patients

2017

Rheumatoid arthritis (RA) is characterized by synovial lining hyperplasia, which involves abnormal growth of fibroblast-like synoviocytes (FLSs). This study aimed to investigate the function and molecular mechanism of peptidylarginine deiminase type 4 (PADI4) in FLSs isolated from RA patients (RA-FLSs). FLSs were isolated from RA patients and transfected with small interfering RNAs (siRNAs) or PADI4 overexpression plasmid. FLSs were treated by Adriamycin (ADR) to induce apoptosis, and apoptotic cells were detected by flow cytometry. The expression of PADI4, p53 and p21 was detected by qRT-PCR and Western blot analysis. The recruitment of PADI4 and histone H3 arginine modifications to p21 promoter was measured by chromatin immunoprecipitation. The results showed that knockdown of PADI4 promoted the apoptosis of RA-FLSs and the expression of p53 and p21. Ectopic expression of PADI4 inhibited ADR-induced apoptosis of RA-FLSs, and down-regulated the expression of p53 and p21. In RA-FLSs, global H3 citrullination (CitH3) and H3 arginine 17 methylation levels were dynamically changed by PADI4 and ADR treatment. PADI4 and H3 could bind p21 promoter region to regulate p21 expression. In conclusion, PADI4 contributes to the pathogenesis of RA by protecting FLSs from apoptosis. PADI4 suppresses p21 transcription through altering histone H3 arginine modifications on p21 promoter region. Our study provides new insight into the anti-apoptotic role of PADI4 in RA development.




Identification of a novel human long non-coding RNA that regulates hepatic lipid metabolism by inhibiting SREBP-1c

2017

Sterol regulatory element binding proteins (SREBPs) are master regulators of hepatic lipid homeostasis. Aberrant expression of SREBPs frequently leads to lipid metabolism dysregulation. Long non-coding RNAs (lncRNAs) have been identified with diverse biological functions, but the effects of lncRNAs on lipid metabolism are rarely reported. Here, we identified a novel human specific lncRNA, lncHR1, as a negative regulator of SREBP-1c expression. Overexpression of lncHR1 inhibited expression of SREBP-1c and fatty acid synthase (FAS) and then repressed oleic acid-induced hepatic cell triglyceride (TG) and lipid droplet (LD) accumulation. In vivo, the data of established transgenic animals showed that mice with lncHR1 expression had less hepatic expression of SREBP-1c, FAS, Acetyl-CoA carboxylase α (ACCα), and less hepatic and plasma TG after being fed a high-fat diet. Therefore, we report a novel lncRNA which can decrease lipid metabolism by repressing SREBP-1c gene expression.




Small role with big impact: miRNAs as communicators in the cross-talk between cancer-associated fibroblasts and cancer cells

2017

Cancer microenvironment is composed of numerous components that can support cancer cell proliferation, promote cancer progression and contribute to cancer treatment resistance. The major components of caner microenvironment are fibroblasts, endothelial cells, immune cells as well as cytokines, chemokines, and extracellular matrix (ECM) all of which surround tumor cells as the core and cross talk with each other. Among them, cancer-associated fibroblasts (CAFs) play an important role in promoting cancer progression by secreting various pro-inflammatory factors. MicroRNAs (miRNAs) are small noncoding RNAs that negatively regulate protein expression both in cancer cell and normal stromal cells. Changes of miRNAs expression in cancer-associated fibroblasts can be induced both by cancer cells and other stromal cells. This change can arise through direct interaction or by secreted paracrine factors or even by secreted miRNAs. The desregulated miRNAs in cancer-associated fibroblasts then enhance the CAFs phenotype and assist their cancer promotion ability. Explore the regulatory function of miRNAs in the complex communication between cancer cells and cancer microenvironment is important to understand the process of tumor progression and may help to develop new therapeutic strategies. This review provides an updated content of latest research advances about the relevance of miRNAs in the interaction between cancer cells and the CAFs. We will describe miRNAs which are differential expressed by NFs and CAFs, their function in regulating fibroblasts activation as well as miRNAs expressed in CAFs as prognostic factors in cancer stroma in recent studies. We will also discuss miRNA as an important player in CAFs mediated regulation of cancer progression and metastasis, cancer metabolism, cancer stem cell property and chemoresistance.




Lyophilized Powder of Catalpol and Puerarin Protected Cerebral Vessels from Ischemia by Its Anti-apoptosis on Endothelial Cells

2017

Catalpol and puerarin are two monomers of Rehmannia glutinosa and Lobed Kudzuvine Root, which are two herbs commonly used together in ancient prescriptions of traditional Chinese medicine for cerebral ischemia. Our previous study shows that the lyophilized powder of the two monomers improved the outcome of cerebral ischemia excellently in rodents. However, if it protects vessels from ischemia is unknown. The present research studied the protection of lyophilized powder of catalpol and puerarin (CP) on endothelial cells and the relative mechanism in vivo and in vitro. Middle cerebral artery occlusion (MCAO) rats were used to study the improvement of CP on neurological deficiency, regional cerebral blood flow (rCBF), and infarct volume. The morphology of vessels and the apoptosis of brain vascular endothelial cells (BVECs) were observed and detected by immunohistochemistry approaches. To study how CP protected primary BVECs (pBVECs) from ischemic penumbra, oxygen glucose deprivation (OGD)-damaged pBVECs were cultured in the condition of insufficient nutrition and low oxygen which recapitulate the low perfusion of ischemic penumbra. Using the cell model, the mechanism by which CP protected pBVECs was studied by shRNA and pathway inhibitors. CP at the dose of 65.4 mg/kg increased regional cerebral blood flow (rCBF), reduced infarct volume, protected vessel integrity and inhibited endothelial cell apoptosis in vivo. But it only improved rCBF, vessel integrity and BVECs apoptosis at the dose of 32.7 mg/kg. In vitro, the protection of CP on pBVECs was proved to be ERK/HIF-1a- and PI3K/AKT/mTOR/HIF-1a-dependent. This study indicates a possibility of CP being a new drug for cerebral ischemia. Besides, this research provides an alternative cell model for penumbra ECs study.




Effects of Photodynamic Therapy Using Yellow LED-light with Concomitant Hypocrellin B on Apoptotic Signaling in Keloid Fibroblasts

2017

Keloid is a common and refractory disease characterized by abnormal fibroblast proliferation and excessive deposition of extracellular matrix components. Hypocrellin B (HB) is a natural perylene quinone photosensitizer. In this experiment, we studied the effects of photodynamic therapy (PDT) using yellow light from light-emitting diode (LED) combined with HB on keloid fibroblasts (KFB) in vitro. Our results showed that HB-LED PDT treatment induced significant KFB apoptosis and decreased KFB cell viability. HB-LED PDT treatment lead to significant BAX upregulation and BCL-2 downregulation in KFB cells, which led to elevation of intracellular free Ca2+ and activation of caspase-3. Our data provides preliminary evidence for the potential of HB-LED PDT as a therapeutic strategy for keloid.




High Production of 2,3-butanediol by a Mutant Strain of the Newly Isolated Klebsiella pneumoniae SRP2 with Increased Tolerance Towards Glycerol

2017

Biodiesel, a renewable fuel produced by transesterification of animal fats and vegetable oils, generates about 10% (v/v) of crude glycerol as a core byproduct. The high volume of this non bio-degradable glycerol is becoming of a great environmental and economical concern due to its worldwide ever-growing surplus. Herein we report a high production of 2,3-butanediol (2,3-BD) from pure and biodiesel derived crude glycerol using a mutant K. pneumoniae SRM2 obtained from a newly isolated strain Klebsiella pneumoniae SRP2. The mutant strain SRM2 with standing high glycerol concentration (220 g L-1 of medium) could rapidly convert glycerol aerobically to 2,3-BD, a versatile product extensively used in chemical, pharmaceutical and fuel industries Our study revealed that an increased GDH activity led to a substantially enhanced production of 2,3-BD. The mutant strain exhibited 1.3-fold higher activity of GDH than that of parent strain (500.08 vs. 638.6 µmol min -1 mg -1 protein), yielding of 32.3 g L-1 and 77.5 g L-1 2,3-BD with glycerol in batch and fed-batch process respectively. However, in batch culture with crude glycerol, cell growth and glycerol consumption were expressively boosted, and 2,3-BD production was 27.7 g L-1 from 75.0 g/L crude glycerol. In this report, the optimal conditions for high production of 2,3-BD were defined in a completely aerobic process, and 0.59 g g-1 product yield of 2,3-BD was attained by the mutated strain K. pneumoniae SRM2, which is the highest amount obtained from batch biotransformation process of glycerol metabolism till today. These results indicated that our newly developed mutant can tolerate high concentration of glycerol, have a high glycerol utilization rate, and high product yield of 2,3-BD. It is demonstrated that the mutant strain K. pneumoniae SRM2 has an ability to produce fewer co-products at trace concentrations at higher glycerol concentrations, and cou[...]



LncRNAs: From Basic Research to Medical Application

2017

This review aimed to summarize the current research contents about long noncoding RNAs (lncRNAs) and some related lncRNAs as molecular biomarkers or therapy strategies in human cancer and cardiovascular diseases. Following the development of various kinds of sequencing technologies, lncRNAs have become one of the most unknown areas that need to be explored. First, the definition and classification of lncRNAs were constantly amended and supplemented because of their complexity and diversity. Second, several methods and strategies have been developed to study the characteristic of lncRNAs, including new species identifications, subcellular localization, gain or loss of function, molecular interaction, and bioinformatics analysis. Third, based on the present results from basic researches, the working mechanisms of lncRNAs were proved to be different forms of interactions involving DNAs, RNAs, and proteins. Fourth, lncRNA can play different important roles during the embryogenesis and organ differentiations. Finally, because of the tissue-specific expression of lncRNAs, they could be used as biomarkers or therapy targets and effectively applied in different kinds of diseases, such as human cancer and cardiovascular diseases.




BEX2 promotes tumor proliferation in colorectal cancer

2017

BEX2 has been suggested to promote the tumor growth in breast cancer and glioblastoma, while inhibit the proliferation of glioma cells. Thus, the role of BEX2 in tumor was still in debate. Additionally, the biological functions of BEX2 in colorectal cancer (CRC) have not yet been clarified. Here, we reported that BEX2 was overexpressed in advanced CRC from both the GSE14333 database and fresh CRC tissue specimens, and positively correlated with clinical staging. Knockdown of BEX2 significantly decreased the in vitro proliferation of SW620 colorectal cancer cells, suppressed subcutaneous xenograft growth and enhanced the survival of mice with cecal tumors. These effects were mainly mediated by the JNK/c-Jun pathway. Knockdown of BEX2 inhibited JNK/c-Jun phosphorylation, while BEX2 overexpression activated JNK/c-Jun phosphorylation. Moreover, the administration of the JNK-specific inhibitor SP600125 to SW620 with BEX2 overexpression abolished the effect of BEX2 on SW620 cell proliferation. This study reveals that BEX2 promotes colorectal cancer cell proliferation via the JNK/c-Jun pathway, suggesting BEX2 as a potential candidate target for the treatment of CRC.




PKD knockdown inhibits pressure overload-induced cardiac hypertrophy by promoting autophagy via AKT/mTOR pathway

2017

Growing evidence shows that protein kinase D (PKD) plays an important role in the development of pressure overload-induced cardiac hypertrophy. However, the mechanisms involved are not clear. This study tested our hypothesis that PKD might mediate cardiac hypertrophy by negatively regulating autophagy using the technique of PKD knockdown by siRNA. Cardiac hypertrophy was induced in 8-week old male C57BL/6 mice by transverse aortic constriction (TAC). TAC mice were then divided into five groups receiving the treatments of vehicle (DMSO), an autophagy inducer rapamycin (1 mg/kg/day, i.p.), control siRNA, lentiviral PKD siRNA (2×108 transducing units/0.1 ml, i.v. injection in one day after surgery, and repeated in 2 weeks after surgery), and PKD siRNA plus 3-methyladenine (3-MA, an autophagy inhibitor, 20 mg/kg/day, i.p.), respectively. Four weeks after TAC surgery, echocardiographic study, hematoxylin and eosin (HE) staining, and Masson's staining showed mice with TAC had significantly hypertrophy and remodeling compared with sham animals. Treatments with PKD siRNA or rapamycin significantly ameliorated the cardiac hypertrophy and dysfunction. Moreover, PKD siRNA increased cardiac autophagic activity determined by electron micrographic study and the biomarkers by Western blot, accompanied with the downregulated AKT/mTOR/S6K signaling pathway. All the cardiac effects of PDK knockdown were inhibited by co-treatment with 3-MA. These results suggest that PKD is involved in the development of cardiac hypertrophy by inhibiting cardiac autophagy via AKT/mTOR pathway.




Disialyl GD2 ganglioside suppresses ICAM-1-mediated invasiveness in human breast cancer MDA-MB231 cells

2017

The disialoganglioside GD3 has been considered to be involved in tumor progression or suppression in various tumor cells. However, the significance of the biological functions of GD3 in breast cancer cells is still controversial. This prompted us to study the possible relationship(s) between GD3 expression and the metastatic potential of a breast cancer MDA-MB231 cells as an estrogen receptor negative (ER-) type. The human GD3 synthase cDNA was transfected into MDA-MB231 cells, and G-418 bulk selection was used to select cells stably overexpressing the GD3 synthase. In vitro invasion potentials of the GD3 synthase over-expressing cells (pc3-GD3s) were significantly suppressed when compared with control cells. Expression of intercellular adhesion molecule-1 (ICAM-1; CD54) was down-regulated in the pc3-GD3s cells and the decrease in ICAM-I expression is directly related to the decrease in invasiveness of the pc3-GD3s cells. Another type of ER negative SK-BR3 cells exhibited the similar level of ICAM-1 expression as MDA-MB231 cells, while the ER positive MCF-7 cells (ER+) showed the increased expression level of ICAM-1. Then, we investigated signaling pathways known to control ICAM-1 expression. No difference was observed in the phosphorylation of ERK and p38 between the pc3-GD3s and control cells (pc3), but the activation of AKT was inhibited in pc3-GD3s, and not in the control (pc3). In addition, the composition of total gangliosides was changed between control (pc3) and pc3-GD3s cells, as confirmed by HPTLC. The pc3-GD3s cells had an accumulation of the GD2 instead of the GD3. RT-PCR results showed that not only GD3 synthase, but also GM2/GD2 synthase (β4-GalNc T) expression was increased in pc3-GD3s cells. Overexpression of GD3 synthase suppresses the invasive potential of human breast cance[...]



Sirtuin 3 is required for osteogenic differentiation through maintenance of PGC-1ɑ-SOD2-mediated regulation of mitochondrial function

2017

Osteogenic differentiation is crucial for the maintenance of bone homeostasis. Sirtuin 3 (SIRT3), a member of sirtuins family, functions as a critical deacetylase that regulates many key proteins. In the current study, we aimed to clarify the role of SIRT3 in osteogenic differentiation and the possible mechanisms, using mouse pre-osteoblastic MC3T3-E1 cells. Expression of SIRT3 was substantially increased in differentiated MC3T3-E1 cells. Knock down of SIRT3 significantly decreased alkaline phosphatase (ALP) staining, and mRNA expression of runt-related transcription factor 2 (Runx2) and collagen type I ɑ 1 (Col1ɑ1), and osteocalcin in differentiated MC3T3-E1 cells. Overexpression of wild type but not mutant SIRT3 could reverse SIRT3 knockdown-resulted decrease of ALP staining. Complex I, II, III, IV, and V activities, oxygen consumption and mitochondrial membrane potential were significantly decreased by SIRT3 knockdown. Moreover, SIRT3 knockdown reduced mitochondrial density, increased mitochondrial size and decreased the expression of NRF1 and TFAM. Knock down of SIRT3 decreased mRNA and protein expression of SOD2 and increased ROS level. Overexpression of SOD2 significantly suppressed SIRT3 knockdown-induced decrease of mitochondrial function and osteogenic differentiation. SIRT3 knockdown resulted in a significant decrease of PGC-1ɑ protein expression but not mRNA expression. Overexpression of wild type but not mutant SIRT3 could reverse SIRT3 knockdown-resulted decrease of PGC-1ɑ protein expression. Moreover, we detected a direct interaction between SIRT3 and PGC-1ɑ and SIRT3 knockdown reduced SIRT3 and PGC-1ɑ interaction, resulting in a reduction of PGC-1ɑ protein stability and PGC-1ɑ-binding in the promoters of SOD2. Overex[...]



Melatonin Inhibits Glioblastoma Stem-like cells through Suppression of EZH2-NOTCH1 Signaling Axis

2017

Glioblastoma stem-like cells (GSCs) play essential roles in glioma growth, radio- and chemo-resistance, and recurrence. Elimination of GSCs has therefore become a key strategy and challenge in glioblastoma therapy. Here, we show that melatonin, an indolamine derived from I-tryptophan, significantly inhibited viability and self-renewal ability of GSCs accompanied by a decrease of stem cell markers. We have identified EZH2-NOTCH1 signaling as the key signal pathway that regulated the effects of melatonin in the GSCs. Instead of transcriptionally silencing gene expression by generating a methylated epigenetic mark at histone 3 at lysine 27 (H3K27), EZH2 regulates NOTCH1 expression by directly binding to the NOTCH1 promoter. Moreover, correlation between the expressions of EZH2 and NOTCH intracellular domain 1 (NICD1) was observed in the clinical tumor samples, evidently supporting the existence of EZH2-NOTCH1 interaction in the gliomas and GSCs. Collectively, we demonstrated that melatonin, a potential tumor inhibitor, performs its function partly by suppressing GSC properties through EZH2-NOTCH1 signaling axis.




Exosomes Secreted from Human-Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells Prevent Osteonecrosis of the Femoral Head by Promoting Angiogenesis

2017

Background: Local ischemia is the main pathological performance in osteonecrosis of the femoral head (ONFH). There is currently no effective therapy to promote angiogenesis in the femoral head. Recent studies revealed that exosomes secreted by induced pluripotent stem cell-derived mesenchymal stem cells (iPS-MSC-Exos) have great therapeutic potential in ischemic tissues, but whether they could promote angiogenesis in ONFH has not been reported, and little is known regarding the underlying mechanism.Methods: iPS-MSC-Exos were intravenously injected to a steroid-induced rat osteonecrosis model. Samples of the femoral head were obtained 3 weeks after all the injections. The effects were assessed by measuring local angiogenesis and bone loss through histological and immunohistochemical (IHC) staining, micro-CT and three-dimensional microangiography. The effects of exosomes on endothelial cells were studied through evaluations of proliferation, migration and tube-forming analyses. The expression levels of angiogenic related PI3K/Akt signaling pathway of endothelial cells were evaluated following stimulation of iPS-MSC-Exos. The promoting effects of exosomes were re-evaluated following blockade of PI3K/Akt.Results: The in vivo study revealed that administration of iPS-MSC-Exos significantly prevented bone loss, and increased microvessel density in the femoral head compared with control group. We found that iPS-MSC-Exos significantly enhanced the proliferation, migration and tube-forming capacities of endothelial cells in vitro. iPS-MSC-Exos could activate PI3K/Akt signaling pathway in endothelial cells. Moreover, the promoting effects of iPS-MSC-Exos were abolished after blockade of PI3K/Akt on endothelial cells.Conclusion[...]



Hyperhomocysteinemia Exacerbates Cisplatin-induced Acute Kidney Injury

2017

Hyperhomocysteinemia (HHcy) has been linked to several clinical manifestations including chronic kidney disease. However, it is not known whether HHcy has a role in the development of acute kidney injury (AKI). In the present study, we reported that HHcy mice developed more severe renal injury after cisplatin injection and ischemia-reperfusion injury shown as more severe renal tubular damage and higher serum creatinine. In response to cisplatin, HHcy mice showed more prevalent tubular cell apoptosis and decreased tubular cell proliferation. Mechanistically, a heightened ER stress and a reduced Akt activity were observed in kidney tissues of HHcy mice after cisplatin injection. Stimulating cultured NRK-52E cells with Hcy significantly increased the fraction of cells in G2/M phase and cell apoptosis together with decreased Akt kinase activity. Akt agonist IGF-1 rescued HHcy-induced cell cycle arrest and cell apoptosis. In conclusion, the present study provides evidence that HHcy increases the sensitivity and severity of AKI.




Increase in Peripheral Blood Intermediate Monocytes is Associated with the Development of Recent-Onset Type 1 Diabetes Mellitus in Children

2017

Monocytes play important roles in antigen presentation and cytokine production to achieve a proper immune response, and are therefore largely implicated in the development and progression of autoimmune diseases. The aim of this study was to analyze the change in the intermediate (CD14+CD16+) monocyte subset in children with recent-onset type 1 diabetes mellitus (T1DM) and its possible association with clinical parameters reflecting islet β-cell dysfunction. Compared with age- and sex-matched healthy controls, intermediate monocytes were expanded in children with T1DM, which was positively associated with hemoglobin A1C and negatively associated with serum insulin and C-peptide. Interestingly, the intermediate monocytes in T1DM patients expressed higher levels of human leukocyte antigen-DR and CD86, suggesting better antigen presentation capability. Further analysis revealed that the frequency of CD45RO+CD4+ memory T cells was increased in the T1DM patients, and the memory T cell content was well correlated with the increase in intermediate monocytes. These results suggest that expanded intermediate monocytes are a predictive factor for the poor residual islet β-cell function in children with recent-onset T1DM.




Reverse the Resistance to PARP Inhibitors

2017

One of the DNA repair machineries is activated by Poly (ADP-ribose) Polymerase (PARP) enzyme. Particularly, this enzyme is involved in repair of damages to single-strand DNA, thus decreasing the chances of generating double-strand breaks in the genome. Therefore, the concept to block PARP enzymes by PARP inhibitor (PARPi) was appreciated in cancer treatment. PARPi has been designed and tested for many years and became a potential supplement for the conventional chemotherapy. However, increasing evidence indicates the appearance of the resistance to this treatment. Specifically, cancer cells may acquire new mutations or events that overcome the positive effect of these drugs. This paper describes several molecular mechanisms of PARPi resistance which were reported most recently, and summarizes some strategies to reverse this type of drug resistance.




ssc-miR-7134-3p regulates fat accumulation in castrated male pigs by targeting MARK4 gene

2017

Castration of male pigs is a common practice used to reduce boar taint in commercial pork production, but it also significantly results in fat accumulation in carcass. Our previous study revealed a miRNA gene, ssc-miR-7134-3p that was implicated in adipogenesis. However, the relationship between ssc-miR-7134-3p and fat deposition due to castration is unknown. In the present study, we observed that ssc-miR-7134-3p targets the coding sequence (CDS) region of MARK4 based on bioinformatics analysis and dual-luciferase assays. Experiments using silent mutations and sub-cloning showed that ssc-miR-7134-3p binds independently to two adjacent sites in the MARK4 CDS. Subsequently, ssc-miR-7134-3p inhibits MARK4 protein expression in pig fibroblast cells, being consistent with the targeting demonstrated in vitro. We found higher MARK4 protein levels in the back fat of castrated pigs than in intact pigs, providing further evidence that MARK4 is involved in regulation of fat deposition. In addition, one SNP (g.2581A>G) in MARK4 was significantly associated with the back fat trait in Chinese and European pig populations. Taken together, we would conclude that ssc-miR-7134-3p targets the MARK4 gene for fat accumulation in the castrated male pigs.




Activated ClC-2 Inhibits p-Akt to Repress Myelination in GDM Newborn Rats

2017

This study aims to investigate the effect and mechanism of type 2 voltage-gated chloride channel (ClC-2) on myelin development of newborn rats' cerebral white matter with gestational diabetes mellitus (GDM). In this study, GDM model was induced in late pregnant rat model. The alteration of ClC-2 expression in various developmental stages of cerebral white matter with/without being exposed to high glucose was analyzed using RT-PCR, active oxygen detection, TUNEL staining, Western Blot as well as immuno-histochemical staining. Our results showed that ClC-2 mRNA and protein expressions in GDM group were significantly increased in white matter of fetal rats after E18 stage, and elevated the level of TNF-α and iNOS in white matter at P0 and P3 stage of newborn rats. Meanwhile, In GDM group, reactive oxygen species (ROS) levels of the white matter at E18, P0, and P3 stage were significantly higher than control group. Furthermore, the expression level of myelin transcription factor Olig2 at P0 stage and CNPase at P3 stage were strikingly lower than that of the control group. In GDM group, ClC-2 expression in the corpus callosum (CC) and cingulate gyrus (CG) regains, and TUNEL positive cell number were increased at P0 and P3 stage. However, PDGFα positive cell number at P0 stage and CNPase expression at P3 stage were significantly decreased. Caspase-3 was also increased in those white matter regions in GDM group, but p-Akt expression was inhibited. While DIDS (a chloride channel blocker) can reverse these changes. In conclusion, ClC-2 and caspase-3 were induced by GDM, which result[...]



Diallyl Trisulfide Inhibits Growth of NCI-H460 in Vitro and in Vivo, and Ameliorates Cisplatin-Induced Oxidative Injury in the Treatment of Lung Carcinoma in Xenograft Mice

2017

Diallyl trisulfide (DATS), an organosulfuric component of garlic oil, exhibits potential anticancer and chemopreventive effects. Cisplatin (DDP), a common chemotherapeutic agent, has provided great therapeutic contributions to treating solid tumors, but with serious side effects. Here, we verified the anti-tumor properties of DATS on lung cancer in vitro and in vivo, and evaluated synergistic effects of DATS combined with DDP on the NCI-H460 xenograft model. Significantly decreased cell viabilities, cell cycle G1 arrest, and apoptosis induction were observed in DATS treated NCI-H460 cells (p<0.05). And injection of DATS (30 or 40 mg/kg) to female Balb/c mice significantly inhibited the growth of human NCI-H460 cell tumor xenograft (p<0.001). Moreover, DATS in combination with DDP exhibited enhanced anti-tumor activity via induction of apoptosis. Apoptosis pathways were confirmed by modulation of p53, Bcl-2 family members; induction of active caspase-3/8/9 and activation of JNK- and p38-MAPK pathways. Interestedly, DATS+DDP administration exerted fewer side effects, such as suppressing the weight loss and ameliorating DDP-induced oxidative injury, especially in renal parenchyma. In addition, increased E-cadherin and decreased MMP-9 expression levels were observed in DATS-treated tumor tissues. These studies provide supports that DATS might be a potential candidate for combination with DDP in cancer treatment.




Regulatory Axis of miR-195/497 and HMGA1-Id3 Governs Muscle Cell Proliferation and Differentiation

2017

Myocytes withdraw from the cell cycle to differentiate during muscle development. Given the capacity of microRNAs (miRNAs) to regulate gene expression during development, we screened for miRNAs that were associated with muscle development. S-Poly(T) Plus analysis of 273 miRNAs in porcine longissimus dorsi muscles revealed 14 miRNAs that were strongly upregulated with age of postnatal muscle development in vivo, including miR-195 and miR-497. These two miRNAs were also strongly upregulated at late differentiation stages of mouse skeletal myoblast C2C12 cells, and demethylation treatment induced significant upregulation of miR-195/497. Manipulation of miR-195/497 expression resulted in dramatic changes in the proliferation and differentiation of C2C12 cells. We identified high-mobility group AT-hook 1 (Hmga1) mRNA as a highly conserved target of miR-195/497 in C2C12 myoblasts. Overexpression of miR-195/497 or Hmga1 silencing in C2C12 cells promoted myogenic differentiation. Moreover, we showed that miR-195/497 repressed Hmga1, which in turn downregulated one of the HMGA1 downstream targets Id3, whose inhibitory effect on myogenic differentiation is well established. Our study revealed a subset of potential development-associated miRNAs and suggests a novel regulatory axis for myogenesis in which miR-195/497 promote myogenic differentiation by repressing the HMGA1-Id3 pathway.




17beta-estradiol Attenuates TNF-α-Induced Premature Senescence of Nucleus Pulposus Cells through Regulating the ROS/NF-κB Pathway

2017

Background: Accelerated cellular senescence within the nucleus pulposus (NP) region is a common feature of disc degeneration. Our previous work indicated that TNF-α promoted NP cell senescence. Although the intervertebral disc has been reported to be an estrogen-sensitive tissue, it is unclear whether estrogen can inhibit premature senescence of NP cells.Objective: To investigate whether 17beta-estradiol (E2) can attenuate TNF-α-induced premature senescence of NP cells and the potential mechanism behind this regulatory process.Methods: Isolated NP cells and intact intervertebral discs from healthy rats were cultured with or without TNF-α, E2 or their combination. The pan estrogen receptor (ER) antagonist ICI 182780 was used to investigate the role of ER. Direct and indirect indicators including cell proliferation, SA-β-Gal activity, telomerase activity, cell cycle, and the expression of matrix macromolecules (aggrecan and collagen II) and senescence markers (p16 and p53) were used to evaluate the premature senescence of NP cells. Additionally, intracellular reactive oxygen species (ROS) and NF-κB/p65 activity were also detected in the NP cell cultures.Results: In the NP cell cultures, E2 significantly increased cell proliferation potency, telomerase activity and the expression of matrix macromolecules but attenuated SA-β-Gal activity, senescence marker (p53 and p16) expression and G1 cycle arrest in TNF-α-treated NP cells. Furthermore, E2 inhibited ROS generation and p[...]



Lipocalin-2 Promotes Endoplasmic Reticulum Stress and Proliferation by Augmenting Intracellular Iron in Human Pulmonary Arterial Smooth Muscle Cells

2017

Endoplasmic reticulum (ER) stress, a feature of many conditions associated with pulmonary hypertension (PH), is increasingly recognized as a common response to promote proliferation in the walls of pulmonary arteries. Increased expression of Lipocalin-2 in PH led us to test the hypothesis that Lipocalin-2, a protein known to sequester iron and regulate it intracellularly, might facilitate the ER stress and proliferation in pulmonary arterial smooth muscle cells (PASMCs). In this study, we observed greatly increased Lcn2 expression accompanied with increased ATF6 cleavage in a standard rat model of pulmonary hypertension induced by monocrotaline. In cultured human PASMCs, Lcn2 significantly promoted ER stress (determined by augmented cleavage and nuclear localization of ATF6, up-regulated transcription of GRP78 and NOGO, increased expression of SOD2, and mild augmented mitochondrial membrane potential) and proliferation (assessed by Ki67 staining and BrdU incorporation). Lcn2 promoted ER stress accompanied with augmented intracellular iron levels in human PASMCs. Treatment human PASMCs with FeSO4 induced the similar ER stress and proliferation response and iron chelator (deferoxamine) abrogated the ER stress and proliferation induced by Lcn2 in cultured human PASMCs. In conclusion, Lcn2 significantly promoted human PASMC ER stress and proliferation by augmenting intracellular iron. The up-regulation of Lcn2 probably involved in the pathogenesis and progression of PH.




miR-15a-3p and miR-16-1-3p Negatively Regulate Twist1 to Repress Gastric Cancer Cell Invasion and Metastasis

2017

MicroRNAs are a novel class of gene regulators that function as oncogenes or tumor suppressors. In our current study, we investigated the role of miR-15a-3p and miR-16-1-3p in the regulation of Twist1 expression and EMT process. Our bioinformatics analysis suggested that on the 3' UTR of Twist1, there are two conserved miRNA recognition sites for miR-15a-3p and miR-16-1-3p respectively. Interestingly, overexpression of miR-15a-3p and miR-16-1-3p significantly suppressed the activity of luciferase reporter containing Twist1-3' UTR, reduced mRNA and protein level of EMT related genes such as TWIST1, N-cadherin, α-SMA and Fibronectin, and repressed MMP9 and MMP2 activity, as well as cell migration and invasion. Conversely, inhibition of miR-15a-3p and miR-16-1-3p significantly increased TWIST1, N-cadherin, α-SMA and Fibronectin protein expression. In addition, Twist1 co-transfection significantly ameliorated the loss of cell migration and invasion. Moreover, overexpression of miR-15a-3p and miR-16-1-3p dramatically suppressed the ability of BGC823 cells to form colonies in vitro and develop tumors in vivo in nude mice. Finally, qPCR and Western blot analysis showed that miR-15a-3p and miR-16-1-3p were significantly reduced in clinical gastric cancer tissue, whereas Twist1 mRNA and protein were significantly up-regulated, suggesting that this aberrant down-regulation of miR-15a-3p and miR-16-1-3p might be associated with the abnormal regulatio[...]



Involvement of Rictor/mTORC2 in cardiomyocyte differentiation of mouse embryonic stem cells in vitro

2017

Rictor is a key regulatory/structural subunit of the mammalian target of rapamycin complex 2 (mTORC2) and is required for phosphorylation of Akt at serine 473. It plays an important role in cell survival, actin cytoskeleton organization and other processes in embryogenesis. However, the role of Rictor/mTORC2 in the embryonic cardiac differentiation has been uncovered. In the present study, we examined a possible link between Rictor expression and cardiomyocyte differentiation of the mouse embryonic stem (mES) cells. Knockdown of Rictor by shRNA significantly reduced the phosphorylation of Akt at serine 473 followed by a decrease in cardiomyocyte differentiation detected by beating embryoid bodies. The protein levels of brachyury (mesoderm protein), Nkx2.5 (cardiac progenitor cell protein) and α-Actinin (cardiomyocyte biomarker) decreased in Rictor knockdown group during cardiogenesis. Furthermore, knockdown of Rictor specifically inhibited the ventricular-like cells differentiation of mES cells with reduced level of ventricular-specific protein, MLC-2v. Meanwhile, patch-clamp analysis revealed that shRNA-Rictor significantly increased the number of cardiomyocytes with abnormal electrophysiology. In addition, the expressions and distribution patterns of cell-cell junction proteins (Cx43/Desmoplakin/N-cadherin) were also affected in shRNA-Rictor cardiomyocytes. Taken together, the results demonstrated that Rictor/mTORC2[...]



The Effect of Estradiol on the Growth Plate Chondrocytes of Limb and Spine from Postnatal Mice in vitro: The Role of Estrogen-Receptor and Estradiol Concentration

2017

Objectives: Skeletal development is a complex process. Little is known about the different response of limb or spine growth plate chondrocytes (LGP or SGP) to the estrogen level and the role of estrogen receptor (ER) during postnatal stage.Methods: LGP and SGP chondrocytes were isolated from 50 one-week mice and treated with different concentrations of 17β-estradiol. Cell viability was measured by cell counting kit-8 (CCK-8). The expression of collagen II and X were evaluated by real-time PCR and Western blotting. Then, the response of LGP or SGP chondrocyte after with or without estradiol and specific ER antagonists to block the effect of ERs were also measured by Western blotting and immunofluorescence.Results: Estradiol promoted the chondrogensis of the chondrocytes in vitro and achieved the maximal expression of type II collagen at the dose of 10-7 M. Additionally, the regulatory effect of estradiol on the chondrogenesis can be mainly relied on ERα. The LGP chondrocytes were more sensitive to the estradiol treatment than SGP in the expression of type II collagen.Conclusions: Estrogen at a pharmacological concentration (10-7 M) could stimulate the maximal production of type II collagen in the growth plate chondrocytes in vitro, which exerts its activity mainly through ERα in the chondrogenesis. Furthermore, the LGP chondrocytes were more sensitive to the estradiol treatment tha[...]



Metadata Analysis of Phanerochaete chrysosporium Gene Expression Data Identified Common CAZymes Encoding Gene Expression Profiles Involved in Cellulose and Hemicellulose Degradation

2017

In literature, extensive studies have been conducted on popular wood degrading white rot fungus, Phanerochaete chrysosporium about its lignin degrading mechanisms compared to the cellulose and hemicellulose degrading abilities. This study delineates cellulose and hemicellulose degrading mechanisms through large scale metadata analysis of P. chrysosporium gene expression data (retrieved from NCBI GEO) to understand the common expression patterns of differentially expressed genes when cultured on different growth substrates. Genes encoding glycoside hydrolase classes commonly expressed during breakdown of cellulose such as GH-5,6,7,9,44,45,48 and hemicellulose are GH-2,8,10,11,26,30,43,47 were found to be highly expressed among varied growth conditions including simple customized and complex natural plant biomass growth mediums. Genes encoding carbohydrate esterase class enzymes CE (1,4,8,9,15,16) polysaccharide lyase class enzymes PL-8 and PL-14, and glycosyl transferases classes GT (1,2,4,8,15,20,35,39,48) were differentially expressed in natural plant biomass growth mediums. Based on these results, P. chrysosporium, on natural plant biomass substrates was found to express lignin and hemicellulose degrading enzymes more than cellulolytic enzymes except GH-61 (LPMO) class enzymes, in early stages. It was observed that the fate of P. chrysosporium transcriptome is signif[...]