👤 Qiligeer Bao

Neuroplasticity and connectivity in the central nervous system (CNS) are easily damaged after hypoxia. Long-term exposure to an anoxic environment can lead to neuropsychiatric symptoms and increases the likelihood of depression. Demyelination is an important lesion of CNS injury that may occur in depression. Previous studies have found that the RhoA/ROCK pathway is upregulated in neuropsychiatric disorders such as multiple sclerosis, stroke, and neurodegenerative diseases. Therefore, the chief aim of this study is to explore the regulatory role of the RhoA/ROCK pathway in the development of depression after hypoxia by behavioral tests, Western blotting, immunostaining as well as electron microscopy. Results showed that HIF-1α, S100β, RhoA/ROCK, and immobility time in FST were increased, sucrose water preference ratio in SPT was decreased, and the aberrant activity of neurocyte and demyelination occurred after hypoxia. After the administration of Y-27632 and fluoxetine in hypoxia, these alterations were improved. Lingo1, a negative regulatory factor, was also overexpressed after hypoxia and its expression was decreased when the pathway blocked. However, fluoxetine had no effect on the expression of Lingo1. Then, we demonstrated that demyelination was associated with failures of oligodendrocyte precursor cell proliferation and differentiation and increased apoptosis of oligodendrocytes. Collectively, our data indicate that the RhoA/ROCK pathway plays a vital role in the initial depression during hypoxia. Blocking this pathway in the early stage of hypoxia can enhance the effectiveness of antidepressants, rescue myelin damage, and reduce the expression of the negative regulatory protein of myelination. The findings provide new insight into the prophylaxis and treatment of depression. Show less

This is a comprehensive review and analysis of 254 cases tested consecutively in the in-house College of American Pathologist-accredited molecular genetics laboratory within the New York City Office of Chief Medical Examiner between October 2015 and February 2018, using a multigene cardiac panel composed of 95 genes associated with cardiac channelopathy and cardiomyopathy. Demographics, autopsy findings, medical history, and postmortem genetic testing results were collected for each case. The majority of decedents were adults (>25 years old, 52.7%), followed by infants (<12 months, 25.6%), young adults (19-25 years old, 11.4%), and children (1-18 years old, 10.2%). There were more males (64.2%) than females (35.8%). The racial/ethnic composition of decedents was 40.2% Black, 29.9% Hispanic, 22.4% White, 5.1% Asian/Pacific Islander, and 2.8% mixed/unspecified. Overall, 45.7% of decedents had a negative autopsy, and the remaining had one to four cardiac findings (cardiac hypertrophy, dilation, atherosclerosis, and fatty change). Twenty-seven pathogenic/likely pathogenic variants (P/LP) and 99 variants of uncertain significance (VUS) were identified in 10.6% and 39% of decedents respectively. P/LP and VUS were found in 51 cardiac genes of the total 95 genes, where MYBPC3, TTN (predicted truncating variants), KCNH2, RYR2 and DSP genes had more than two P/LP variants identified. Among the 73 decedents who were suspected of having cardiac arrhythmia or cardiomyopathy, 20.3% had P/LP variants and 47.9% had VUS; among 23 decedents who had hypertensive cardiovascular diseases and 20 decedents with a history of substance use, 13% and 30% had P/LP variants, respectively. There were 26 referrals from medical examiners for genetic counseling and the outcomes are discussed. The study demonstrates characteristics of the diverse population typically seen by medical examiners in an urban center and our results support a broader implementation of molecular testing in sudden death. Show less

Long non-coding RNAs (lncRNAs) function as a class of significant mediators in prostate cancer (PCa), and this study mainly discussed the molecular mechanism of lncRNA growth arrest-specific 5 (GAS5) in PCa progression and radiosensitivity. GAS5 and microRNA-320a (miR-320a) levels were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and migration were severally examined through 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) and transwell assays. PCa cells were treated with X-ray irradiation. Cell survival and apoptosis rate were assayed using colony formation assay and flow cytometry, respectively. The apoptosis-related protein and Rab GTPase 21 ( GAS5 was down-regulated in PCa tissues and cells. GAS5 overexpression suppressed cell viability and migration while facilitated radiosensitivity of PCa cells. GAS5 was a molecular sponge of miR-320a. The effects of GAS5 up-regulation on PCa cells were accomplished by sponging miR-320a. MiR-320a targeted Collectively, GAS5 restrained tumor development and expedited the radiosensitivity in PCa by the miR-320a/ Show less

Diabetic nephropathy (DN) is one of the severe complications of diabetes. Nowadays, effective treatment for end-stage renal disease (ESRD) patients is still limited. HK-2 cells were stimulated with serum from phosphate-buffered saline (PBS) or Jiawei Shuilu Erxiandan (JSE)-treated DN mice, then long non-coding RNA (lncRNA) CLYBL-AS2 was discovered by RNA sequence, following the comparison of the serum from normal patients with DN patients to confirm the role of lncCLYBL-AS2. Next, we performed Show less

This study investigates the antifibrotic activities and potential mechanisms of costunolide (COS), a natural sesquiterpene compound. Rats subjected to bile duct ligation and mice challenged with CCl In animals, COS administration attenuated hepatic histopathological injury and collagen accumulation and reduced the expression of fibrogenic genes. COS time- and dose-dependently suppressed the levels of fibrotic markers in LX-2 cells and mouse pHSCs. Mechanistic studies showed COS destabilized Notch3 and subsequently inhibited the Notch3-HES1 pathway, thus inhibiting HSC activation. Furthermore, COS blocked the WW domain-containing protein 2 (WWP2)/protein phosphatase 1G (PPM1G) interaction and enhanced the effect of WWP2 on Notch3 degradation. COS exerted potent antifibrotic effects in vitro and in vivo by disrupting the WWP2/PPM1G complex, promoting Notch3 degradation and inhibiting the Notch3/HES1 pathway. This indicates that COS may be a potential therapeutic candidate for the treatment of liver fibrosis. Show less

Being a hydroxylated metabolite of aflatoxin B1 (AFB1) and the most threatening aspect of AFB1 contamination, aflatoxin M1 (AFM1) can lead to hepatotoxicity and hepato-carcinogenicity, and possess intestinal cytotoxicity. However, little is known about the potential mechanisms of the extrahepatic effect. The aim of this study was to investigate intestinal dysfunction induced by AFM1 via transcriptome analysis. Gene expression profiling was analyzed to comparatively characterize the differentially expressed genes (DEGs) after differentiated Caco-2 cells were exposed to different concentrations of AFM1 for 48 h. A total of 165 DEGs were significantly clustered into two down-regulated patterns. Protein-protein interaction (PPI) network analysis based on Search Tool for Retrieval of Interacting Genes (STRING)suggested that 23 key enzymes mainly participated in the regulation of the cell cycle. Q-PCR analysis was performed to validate that key 12 genes (BUB1, BUB1B, MAD2L1, CCNA2, RB1, CDK1, ANAPC4, ATM, KITLG, PRKAA2, SIRT1, and SOS1) were involved. This study firstly revealed that the toxicity of AFM1 to intestinal functions may be partly due to the occurrence of cell cycle arrest, which is linked to changes in CDK1, SOS1/Akt, and AMPK signaling molecules. Show less

The T-cell-inflamed phenotype correlates with efficacy of immune-checkpoint blockade, whereas non-T-cell-inflamed tumors infrequently benefit. Tumor-intrinsic WNT/β-catenin signaling mediates immune exclusion in melanoma, but association with the non-T-cell-inflamed tumor microenvironment in other tumor types is not well understood. Using The Cancer Genome Atlas (TCGA), a T-cell-inflamed gene expression signature segregated samples within tumor types. Activation of WNT/β-catenin signaling was inferred using three approaches: somatic mutations or somatic copy number alterations (SCNA) in β-catenin signaling elements including Across TCGA, 3,137/9,244 (33.9%) tumors were non-T-cell-inflamed, whereas 3,161/9,244 (34.2%) were T-cell-inflamed. Non-T-cell-inflamed tumors demonstrated significantly lower expression of T-cell inflammation genes relative to matched normal tissue, arguing for loss of a natural immune phenotype. Mutations of β-catenin signaling molecules in non-T-cell-inflamed tumors were enriched three-fold relative to T-cell-inflamed tumors. Across 31 tumors, 28 (90%) demonstrated activated β-catenin signaling in the non-T-cell-inflamed subset by at least one method. This included target molecule expression from somatic mutations and/or SCNAs of β-catenin signaling elements (19 tumors, 61%), pathway analysis (14 tumors, 45%), and increased β-catenin protein levels (20 tumors, 65%). Activation of tumor-intrinsic WNT/β-catenin signaling is enriched in non-T-cell-inflamed tumors. These data provide a strong rationale for development of pharmacologic inhibitors of this pathway with the aim of restoring immune cell infiltration and augmenting immunotherapy. Show less

Human bocavirus (HBoV) is a member of the genus Bocavirus, family Parvoviridae, and subfamily Parvovirus and was first identified in nasopharyngeal aspirates of Swedish children with acute respiratory tract infection (ARTI) in 2005. It is the causative agent of nasopharyngeal aspirate disease and death in children. The HboV genomic structure is a linear single-stranded DNA (ssDNA). Its clinical pathogenic characteristics have been extensively studied, however, at present the molecular mechanism underlying the pathogenesis of HBoV infection is not completely clear. In this study, a total of 293 differentially expressed proteins (DEPs) between ARTI cases and healthy plasma samples were characterized using isobaric tags for relative and absolute quantitation (iTRAQ)-coupled bioinformatics analysis, among which 148 were up-regulated and 135 were down-regulated. Gene Ontology (GO) and Cluster of Orthologous Groups of proteins (COG) annotated an enrichment of DEPs in complement activation and biological processes like immunity, inflammation, signal transduction, substance synthesis, and metabolism. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis enriched DEPs mainly in the Wnt signaling pathway (ko04310), PPAR signaling pathway (ko03320), intestinal immune network for IgA production (ko04672), complement and coagulation cascades (ko04610), Toll-like receptor signaling pathway (ko04620) and B cell receptor signaling pathway (ko04662). Further, expression levels of three candidate proteins (upregulated PPP2R1A and CUL1, and downregulated CETP) were validated using western blotting. Our investigation is the first analysis of the proteomic profile of HBoV-infected ARTI cases using the iTRAQ approach, providing a foundation for a better molecular understanding of the pathogenesis of ARTI in children. Show less

Notwithstanding the researches on biomarkers and targeted therapies in renal cell carcinomas (RCC) have made progress in the last decades, the application of the biomarkers and targeted therapy agents for RCC in clinic are restricted because of their limitation or side effects. Liver X receptors (LXRs) and the NLRP3 inflammasome have been the research hotspots in recent years. In our study, we integrated bioinformatics analysis, molecular biology experiments and biological function experiments to study the roles of LXRα and the NLRP3 inflammasome in RCC. The study demonstrated that the elevated LXRα expression is correlated with a poor prognosis in RCC. Furthermore, our study revealed the expression levels and roles of the NLRP3 inflammasome in RCC for the first time. This research demonstrated that LXRα could promote the metastasis of RCC cells by suppressing the expression of the NLRP3 inflammasome. In Brief, LXRα had the possibility to be a novel diagnostic and prognostic biomarker and therapeutic target in renal cell cancer and LXRα could regulate the metastasis of renal cell cancer via NLRP3 inflammamsome. Show less

Circular RNAs (circRNAs) comprise a class of noncoding RNA molecules that play an important role in several normal cellular functions, as well as tumorigenesis in humans. However, the expression patterns and biological functions of circRNAs in ovarian cancer (OC) remain unclear. Therefore, we investigated the expression profiles and biological functions of certain circRNAs in OC tumor tissues. The expression of three circRNAs (VPS13C-has-circ-001567, RAD50-has-circ-00718, and SPECC1-has-circ-000013) was detected by real-time polymerase chain reaction in OC cell lines, and also in tumor and pericarcinous tissues obtained from 20 patients with OC. The function of VPS13C-has-circ-001567 in SKOV3 and OV-1063 cells was investigated by knockdown of VPS13C-has-circ-001567 and then analyzing any resultant effects on the cell cycle, cell proliferation, apoptosis, and cell invasion ability. E-cadherin and N-cadherin expressions were analyzed by immunofluorescence and western blotting. Finally, the tumorigenicity of OC cells was assessed in nude mice. The results showed that VPS13C-has-circ-001567 was expressed at significantly higher levels in OC tumor tissues compared with pericarcinous tissues, and this overexpression was associated with tumor node metastasis stage and lymph node metastasis. We found that knockdown of VPS13C-has-circ-001567 significantly promoted apoptosis and inhibited the proliferation of SKOV3 and OV-1063 cells in vitro. Knockdown of VPS13C-has-circ-001567 led to cell cycle arrest at G1 phase and decreased the percentage of S1 phase cells. Additionally, knockdown of VPS13C-has-circ-001567 decreased the invasion ability of SKOV3 and OV-1063 cells, and also changed the levels of E-cadherin and N-cadherin expressions. Knockdown of VPS13C-has-circ-001567 significantly reduced the tumorigenicity of OC cells. Taken together, our results suggest that VPS13C-has-circ-001567 plays a role in the development of OC and might be a prognostic marker and therapeutic target for OC. Show less

A high level of APOC3 expression is an independent risk factor for some lipid metabolism-related diseases, such as cardiovascular disease (CVD), nonalcoholic fatty liver disease (NAFLD) and atherosclerosis (AS). This suggests that down-regulating APOC3 expression is a potential way of regulating lipid levels. In this study, we used luciferase reporter screening to identify a natural compound, alantolactone (ALA), that can inhibit the promoter activity of APOC3. ALA decreased APOC3 expression at both mRNA and protein levels. Then we pretreated L02 liver cells with oxLDL to investigate the function of ALA in lipid homeostasis. Intriguingly, ALA attenuated oxLDL-induced foam cell formation by reducing total cholesterol (TC) and triglyceride (TG) contents. Furthermore, these results could be reversed by overexpressing APOC3 protein. ALA inhibited tyrosine phosphorylation (Tyr705pho) of STAT3 to down-regulate APOC3 expression. Intriguingly, overexpression of a wild-type STAT3 or a constitutively active form of STAT3 (STAT3-C) up-regulated APOC3 expression and partly reversed the effect of ALA in oxLDL-induced L02 cells. Overexpression of wild-type STAT3 also increased TC but not TG contents in L02 cells. However, overexpression of STAT3-C significantly increased TC and TG contents, and the effect of ALA was partly attenuated by STAT3-C, although this was not statistically significant. These results suggest that ALA attenuates lipid accumulation through down-regulation of APOC3 expression, at least in part by inhibiting STAT3 signaling. Show less

Proprotein subtilisin kexin type 9 (PCSK9) and lipoprotein (a) [Lp(a)] levels are causative risk factors for coronary heart disease. The objective of the study was to determine the impact of lipid-lowering treatments on circulating PCSK9 and Lp(a). We measured PCSK9 and Lp(a) levels in plasma samples from Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events trial patients with coronary heart disease and/or type II diabetes (T2D) mellitus. Patients received atorvastatin, which was titrated (10, 20, 40, or 80 mg/d) to achieve low-density lipoprotein cholesterol levels <100 mg/dL (baseline) and were subsequently randomized either to atorvastatin + torcetrapib, a cholesterol ester transfer protein inhibitor, or to atorvastatin + placebo. At baseline, both plasma PCSK9 and Lp(a) were dose-dependently increased with increasing atorvastatin doses. Compared with patients without T2D, those with T2D had higher PCSK9 (357 ± 123 vs 338 ± 115 ng/mL, P = .0012) and lower Lp(a) levels (28 ± 32 vs 32 ± 33 mg/dL, P = .0005). Plasma PCSK9 levels significantly increased in patients treated with torcetrapib (+13.1 ± 125.3 ng/mL [+3.7%], P = .005), but not in patients treated with placebo (+2.6 ± 127.9 ng/mL [+0.7%], P = .39). Plasma Lp(a) levels significantly decreased in patients treated with torcetrapib (-3.4 ± 10.7 mg/dL [-11.1%], P < .0001), but not in patients treated with placebo (+0.3 ± 9.4 mg/dL [+0.1%], P = .92). In patients at high cardiovascular disease risk, PCSK9 and Lp(a) are positively and dose-dependently correlated with atorvastatin dosage, whereas the presence of T2D is associated with higher PCSK9 but lower Lp(a) levels. Cholesterol ester transfer protein inhibition with torcetrapib slightly increases PCSK9 levels and decreases Lp(a) levels. Show less

It has been announced in accumulative studies that non-coding (nc)RNAs are responsible for a varieties of biological behaviors during the progression of tumors. As two subgroups of ncRNAs family, micro (mi)RNAs can interact with long non-coding (lnc)RNAs, thereby forming ceRNA network. In this study, miR-448 was expressed higher in NSCLC tissues (P < 0.01) and NSCLC cell lines (P < 0.01). Moreover, low expression of miR-448 predicted poor prognosis for patients with NSCLC (P < 0.001). Functional assays revealed the anti-oncogenic function of miR-448 in NSCLC by inhibiting cell proliferation, invasion, migration and epithelial-mesenchymal transition (EMT). Mechanically, miR-448 was found to be negatively regulated by lncRNA PRNCR1 (prostate cancer non-coding RNA 1). Moreover, HEY2 (Hairy and enhancer of split-related with YRPW motif protein 2) was demonstrated to be the target mRNA of miR-448 in NSCLC cells. All mechanism experiments revealed that lncRNA PRNCR1 exerted ceRNA function in NSCLC by regulating miR-448 and HEY2. To validate the function of PRNCR1-miR-488-HEY2 network in NSCLC progression, rescue assays were conducted. Taken all together, we confirmed that lncRNA PRNCR1 upregulates HEY2 to promote tumor progression in NSCLC by competitively binding miR-448. Show less

A recent study analyzed 2053 multiple sclerosis (MS) cases and 799 healthy controls to investigate whether five genetic variants (rs11039149, rs12221497, rs2279238, rs7120118 and rs7114704) in NR1H3 are associated with MS risk. However this study reported negative results. It is very important that the appropriate samples and approach should be used in replication studies, which may provide the correct interpretation of the results. Here, we evaluated the above findings using large-scale MS genome-wide association studies with a total of 27,148 samples including 9772 MS cases and 17,376 controls, and multiple expression quantitative trait loci datasets. The results suggest that rs7120118 and rs2279238 variants are significantly associated with MS risk, and could significantly regulate NR1H3 expression in kinds of human tissues and cells. In summary, these findings provide important supplementary information about the association between NR1H3 variants and MS risk. Show less

We aim to validate the effects of glucose-dependent insulinotropic polypeptide (GIP) on fat distribution and glucose metabolism in Han Chinese populations. We genotyped six tag single-nucleotide polymorphisms (SNPs) of GIP and four tag SNPs of glucose-dependent insulinotropic polypeptide receptor (GIPR) among 2884 community-based individuals from Han Chinese populations. Linear analysis was applied to test the associations of these variants with visceral fat area (VFA) and subcutaneous fat area (SFA) quantified by magnetic resonance imaging as well as glucose-related traits. We found that the C allele of rs4794008 of GIP tended to increase the VFA and the VFA/SFA ratio in all subjects (P=0.050 and P=0.054, respectively), and rs4794008 was associated with the VFA/SFA ratio in males (P=0.041) after adjusting for the BMI. The VFA-increasing allele of rs4794008 was not related to any glucose metabolism traits. However, rs9904288 of GIP was associated with the SFA in males as well as glucose-related traits in all subjects (P range, 0.004-0.049), and the GIPR variants displayed associations with both fat- and glucose-related traits. The results could provide the evidence that GIP might modulate visceral fat accumulation via incretin function or independent of incretin. Show less

To evaluate the independent and joint effects of FADS1 polymorphism and fish oil intake on oral squamous cell carcinoma( OSCC). A case-control study was conducted with 259 newly diagnosed primary OSCC patients and538 controls frequency-matched by sex and age in Fujian from September 2010 to September 2014. Data on demographics and dietary habits such as marine fish oil intake were collected using a structure questionnaire. FADS1 rs174549 genotype was determined using Taq Man genotyping assays. Unconditional logistic regression was used to the oddsratios( ORs) and their 95% confidence intervals( CI) of FADS1 polymorphism and fish oil intake for OSCC. FADS1 rs174549 AA genotype was associated with decreased risk of OSCC( codominant model: OR = 0. 53, 95% CI 0. 33-0. 85; recessive model: OR = 0. 57, 95% CI 0. 38-0. 87). Compared with those who non-intake marine fish oil, regularly intake of marine fish oil decreased the risk of OSCC( OR = 0. 54, 95%CI: 0. 32-0. 91). Moreover, a multiplicative interaction between FADS1 rs174549 polymorphism and marine fish oil intake for oral cancer( OR₍multiplicative)= 0. 31, 95% CI0. 11-0. 87). FADS1 rs174549 polymorphism and marine fish oil intake may be independent protective factors for OSCC with a gene-diet multiplicative interaction. Show less

Excess ammonia is produced during fasting when amino acids are used for glucogenesis. Together with ureagenesis, glucogenesis occurs in periportal hepatocytes mediated mainly through the peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). In vivo experiments showed that fasting strongly stimulated mice glucagon secretion, hepatic PGC-1α, sirtuin 3 (SIRT3) and sirtuin 5 (SIRT5) expression and ureagenesis enzymatic activity such as carbamoyl phosphate synthetase 1 (CPS1) and ornithine transcarbamoylase (OTC). Interestingly, (15)N-labeled urea and (13)C-labeled glucose production in wild-type mice were significantly increased compared with PGC-1α null mice by [(15)N,(13)C]alanine perfused liver. Glucagon significantly stimulated ureagenesis, expression of SIRT3, SIRT5 and the activities of CPS1 and OCT but did not stimulate PGC-1α silencing hepatocytes in mice periportal hepatocytes. Contrarily, PGC-1α overexpression significantly increased the expression of SIRT3, SIRT5 and the activities of CPS1 and OTC, but induced no significant changes in CPS1 and OTC expression. Morever, SIRT3 directly deacetylates and upregulates the activity of OTC, while SIRT5 deacetylates and stimulates the activity of CPS1. During fasting, PGC-1α facilitates ureagenesis in mouse periportal hepatocytes by deacetylating CPS1 and OTC modulated by mitochondrial deacetylase, SIRT3 and SIRT5. This mechanism may be relevant to ammonia detoxification and metabolic homeostasis in liver during fasting. Show less

The role of ROS in stem cell biology has not been fully illustrated and understood. Here we compared the different responses and investigated the mechanism underlying oxidative stress induced by hydrogen peroxide (H Show less

Phenoxybenzamine hydrochloride (PHEN) is a selective antagonist of both α-adrenoceptor and calmodulin that exhibits anticancer properties. The aim of this study was to explore the anti-tumor function of PHEN in glioma. Cell proliferation assay was used to assess glioma cell growth. Migration and invasion capacity of glioma cells was monitored by wound-healing and transwell assay, respectively. Neurosphere formation test was adopted for the tumorigenesis of glioma cells, which was also confirmed by soft agar cloning formation test in vitro and a nude mouse model in vivo. Finally, we explored the potential pathway utilized by PHEN using Western blot and immunofluoresce staining. PHEN exhibited a significant inhibitory effect on the proliferation of both U251 and U87MG glioma cell lines in a positive dose-dependent manner. PHEN apparently attenuated the malignancy of glioma in terms of migration and invasion and also suppressed the tumorigenic capacity both in vitro and in vivo. Mechanism study showed that PHEN promoted tumor suppression by inhibiting the TrkB-Akt pathway. The results of the present study demonstrated that PHEN suppressed the proliferation, migration, invasion, and tumorigenesis of glioma cells, induced LINGO-1 expression, and inhibited the TrkB-Akt pathway, which may prove to be the mechanisms underlying the anti-tumor effect of PHEN on glioma cells. Show less

We examined the relationship between the liver X receptor α gene (LXRα) polymorphism and the susceptibility to stroke. We utilized the single fluorescent-labeled probe technique to detect the genotype of rs12221497 in the LXRα gene in 400 stroke patients and 400 healthy control subjects. The difference in genotype distribution between the 2 groups was analyzed using the chi-square test. Serum lipids and glucose levels between the different genotypes were also compared. We found that the risk of stroke in carriers with the AA + GA genotype was 2.02-fold higher than that in GG genotype carriers (odds ratio = 2.02, 95% confidence interval = 1.18-2.87, P < 0.05), and that the risk of stroke in carriers with the A allele increased by 0.606-fold compared to that in G allele carriers (odds ratio = 1.606, 95% confidence interval = 1.158-2.228). Logistic regression analysis showed that after adjusting for other confounding factors, the A allele was an independent risk for stroke. However, there were no differences in serum lipids and glucose levels between each genotype. We conclude that the rs12221497 polymorphism in the LXRα gene was associated with the susceptibility to stroke in a Han Chinese population. Show less

Polyubiquitination by E2 and E3 enzymes is a predominant mechanism regulating protein function. Some RING E3s, including anaphase-promoting complex/cyclosome (APC), catalyze polyubiquitination by sequential reactions with two different E2s. An initiating E2 ligates ubiquitin to an E3-bound substrate. Another E2 grows a polyubiquitin chain on the ubiquitin-primed substrate through poorly defined mechanisms. Here we show that human APC's RING domain is repurposed for dual functions in polyubiquitination. The canonical RING surface activates an initiating E2-ubiquitin intermediate for substrate modification. However, APC engages and activates its specialized ubiquitin chain-elongating E2 UBE2S in ways that differ from current paradigms. During chain assembly, a distinct APC11 RING surface helps deliver a substrate-linked ubiquitin to accept another ubiquitin from UBE2S. Our data define mechanisms of APC/UBE2S-mediated polyubiquitination, reveal diverse functions of RING E3s and E2s, and provide a framework for understanding distinctive RING E3 features specifying ubiquitin chain elongation. Show less

Identification of carbohydrate sequences that determine affinity to specific chemokines is a critical step for strategies to interfere with chemokine-mediated leukocyte trafficking. Here, we first characterized the development of allergic asthma in Tie2-dependent and inducible Ext1-knockout (Tie2-Ext1(iKO)) mice. We showed that heparan sulfate is essential for leukocyte recruitment in the peribronchial region and bronchoalveolar lavage fluid (BALF), and is crucial for induction of airway hyperresponsiveness. Our glycan microarray showed a unique affinity profile of chemokine CCL20 to substructures of heparin and heparin-like oligo/di/monosaccharides. Among them, we identified a synthetic and not naturally occurring monosaccharide, 2,4-O-di-sulfated iduronic acid (Di-S-IdoA), as a potential inhibitor for CCL20-heparan sulfate interaction. Mice injected with Di-S-IdoA via tail vain or nasal inhalation showed attenuated leukocyte recruitment into inflammatory sites and BALF. These results demonstrate a critical role of chemokine-heparan sulfate interaction in the asthma development and Di-S-IdoA as a potential drug for asthma treatment. Show less

Type 2 diabetes and its chronic complications have become a worldwide epidemic nowadays. However, its molecular mechanism is still unknown. We have previously identified a novel variant rs12742393 of NOS1AP for type 2 diabetes susceptibility in the Chinese population. In this study, we analyzed the total serum profiling among three genotypes of rs12742393 to discover potential crosstalk under the variant and the disease through proteomic analyses for the first time. We used OFFGEL peptide fractionation, LC-MS/MS analysis, and label-free quantification to profile the fasting human serum samples of the genotypes in rs12742393 (n = 4, for CC, AC, and AA, resp.). Four proteins were identified, including apoA4, alpha1-ACT, HABP2, and keratin 10, with blood levels changed significantly between CC and AA homozygotes of rs12742393. Compared with AA group, the levels of apoA4 increased (P = 0.000265), whereas the concentration of alpha1-ACT, HABP2, and keratin 10 decreased in CC group (P = 0.011116, 0.021175, and 0.015661, resp.). Then we selected additional fasting serum samples for ELISA and western blot validation. However, no significant differences were identified by neither ELISA nor western blot (P > 0.05). The protein profiling changes between the genotypes of rs12742393 indicated that this SNP might play a role in the development of type 2 diabetes. Show less

Prostate cancer is a heterogeneous genetic disease, and molecular methods for predicting prognosis in patients with aggressive form of the disease are urgently needed to better personalize treatment approaches. The objective was to identify host genetic variations in candidate steroidogenic genes affecting hormone levels and prostate cancer progression. The study examined two independent cohorts composed of 526 Caucasian men with organ-confined prostate cancer and 601 Taiwanese men on androgen-deprivation therapy. Caucasians were genotyped for 109 haplotype-tagging single-nucleotide polymorphisms (SNP) in CYP17A1, ESR1, CYP19A1, and HSD3B1, and their prognostic significance on disease progression was assessed using Kaplan-Meier survival curves and Cox regression models. Positive findings, including previously identified SRD5A1, SRD5A2, HSD17B2, HSD17B3, and HSD17B12 polymorphisms, were then explored in Taiwanese men (n = 32 SNPs). The influence of positive markers on the circulating hormonal levels was then appraised in Caucasians using specific and sensitive mass spectrometry-based methods. After adjusting for known risk factors, variants of CYP17A1 (rs6162), HSD17B2 (rs4243229 and rs7201637), and ESR1 (rs1062577) were associated with progressive disease in both cohorts. Indeed, the presence of these variations was significantly associated with progression in Caucasians (HR, 2.29-4.10; P = 0.0014-2 × 10(-7)) and survival in Taiwanese patients [HR = 3.74; 95% confidence interval (CI): 1.71-8.19, P = 0.009]. Remarkably, the CYP17A1 rs6162 polymorphism was linked to plasma dehydroepiandrosterone-sulfate (DHEA-S) levels (P = 0.03), HSD17B2 rs7201637 with levels of dihydrotestosterone (P = 0.03), and ESR1 rs1062577 with levels of estrone-S and androsterone-glucuronide (P ≤ 0.05). This study identifies, in different ethnic groups and at different disease stages, CYP17A1, HSD17B2, and ESR1 as attractive prognostic molecular markers of prostate cancer progression. Show less

Constitutive Wnt signalling is characterized by excessive levels of β-catenin protein and is a frequent occurrence in cancer. APC and Axin are key components of the β-catenin destruction complex that acts to promote β-catenin degradation. The levels of Axin are in turn controlled by tankyrases, members of the PARP-family of poly-ADP-ribosylation enzymes. In colorectal cancer cells, which typically harbor APC mutations, inhibition of tankyrase activity promotes Axin stabilization and attenuates Wnt signalling. Here, we examined the effect of inhibiting tankyrases in breast cancer cells with normal APC. We show that application of the small molecule tankyrase inhibitor, XAV939 or siRNA-mediated abrogation of tankyrase expression increases Axin1 and Axin2 protein levels and attenuates Wnt-induced transcriptional responses in several breast cancer lines. In MDA-MB-231 cells, inhibiton of tankyrase activity also attenuate Wnt3a induced cell migration. Moreover, in both MDA-MB-231 and colorectal cancer cells, XAV939 inhibits cell growth under conditions of serum-deprivation. However, the presence of serum prevents this growth inhibitory effect, although inhibition of Wnt-induced transcriptional and migratory responses was maintained. These results indicate that stabilization of Axin by inhibition of tankyrases alone, may not be an effective means to block tumor cell growth and that combinatorial therapeutic approaches should be considered. Show less

Hepatocyte spheroids have been proposed for drug metabolism studies and in bioartificial liver devices. However, the optimal conditions required to meet the aerobic demands of mitochondria-rich hepatocyte spheroids is not well studied. We hypothesized that an optimal concentration of oxygen could be identified and that the health of hepatocyte spheroids might be further improved by antioxidant therapy. Rat hepatocyte spheroids were maintained in suspension culture for 7 days under a mixture of 5% CO(2) plus O(2):N(2) to achieve fractional oxygen contents of 6%(C1), 21%(C2), 58%(C3), and 95%(C4). Spheroid health was assessed under each condition by vital staining, TEM, oxygen consumption, and mitochondrial counts. Hepatocyte differentiation was assessed by expression of 10 liver-related genes (HNF4a, HNF6, Cyp1A1, albumin, Nags, Cps1, Otc, Ass, Asl, Arg1). Functional markers (albumin and urea) were measured. The influence of oxygen tension and antioxidant treatment on the production of reactive oxygen species (ROS) was assessed by confocal microscopy. We observed that the hepatocyte spheroids were healthiest under normal atmospheric (C2) conditions with antioxidants ascorbic acid and L-carnitine. Cell death and reduced functionality of hepatocyte spheroids correlated with the formation of ROS. Normal atmospheric conditions provided the optimal oxygen tension for suspension culture of hepatocyte spheroids. The formation and deleterious effects of ROS were further reduced by adding antioxidants to the culture medium. These findings have direct application to development of the spheroid reservoir bioartificial liver and the use of hepatocyte spheroids in drug metabolism studies. Show less

The innate immune system detects viral infection predominantly by sensing viral nucleic acids. We report the identification of a viral sensor, consisting of RNA helicases DDX1, DDX21, and DHX36, and the adaptor molecule TRIF, by isolation and sequencing of poly I:C-binding proteins in myeloid dendritic cells (mDCs). Knockdown of each helicase or TRIF by shRNA blocked the ability of mDCs to mount type I interferon (IFN) and cytokine responses to poly I:C, influenza A virus, and reovirus. Although DDX1 bound poly I:C via its Helicase A domain, DHX36 and DDX21 bound the TIR domain of TRIF via their HA2-DUF and PRK domains, respectively. This sensor was localized within the cytosol, independent of the endosomes. Thus, the DDX1-DDX21-DHX36 complex represents a dsRNA sensor that uses the TRIF pathway to activate type I IFN responses in the cytosol of mDCs. Show less

Recent meta-analysis of genome-wide association studies in European descent samples identified novel loci influencing glucose and insulin related traits. In the current study, we aimed to evaluate the association between these loci and traits related to glucose metabolism in the Chinese. We genotyped seventeen single nucleotide polymorphisms (SNPs) from fifteen loci including GIPR, ADCY5, TCF7L2, VPS13C, DGKB, MADD, ADRA2A, FADS1, CRY2, SLC2A2, GLIS3, PROX1, C2CD4B, SLC30A8 and IGF1 in 6,822 Shanghai Chinese Hans comprising 3,410 type 2 diabetic patients and 3,412 normal glucose regulation subjects. MADD rs7944584 showed strong association to type 2 diabetes (p = 3.5×10(-6), empirical p = 0.0002) which was not observed in the European descent populations. SNPs from GIPR, TCF7L2, CRY2, GLIS3 and SLC30A8 were also associated with type 2 diabetes (p = 0.0487∼2.0×10(-8)). Further adjusting age, gender and BMI as confounders found PROX1 rs340874 was associated with type 2 diabetes (p = 0.0391). SNPs from DGKB, MADD and SLC30A8 were associated with fasting glucose while PROX1 rs340874 was significantly associated with OGTT 2-h glucose (p = 0.0392∼0.0014, adjusted for age, gender and BMI), the glucose-raising allele also showed association to lower insulin secretion. IGF1 rs35767 showed significant association to both fasting and 2-h insulin levels as well as insulin secretion and sensitivity indices (p = 0.0160∼0.0035, adjusted for age, gender and BMI). Our results indicated that SNPs from GIPR, TCF7L2, DGKB, MADD, CRY2, GLIS3, PROX1, SLC30A8 and IGF1 were associated with traits related to glucose metabolism in the Chinese population. Show less

Toll-like receptor 9 (TLR9) senses microbial DNA and triggers type I IFN responses in plasmacytoid dendritic cells (pDCs). Previous studies suggest the presence of myeloid differentiation primary response gene 88 (MyD88)-dependent DNA sensors other than TLR9 in pDCs. Using MS, we investigated C-phosphate-G (CpG)-binding proteins from human pDCs, pDC-cell lines, and interferon regulatory factor 7 (IRF7)-expressing B-cell lines. CpG-A selectively bound the aspartate-glutamate-any amino acid-aspartate/histidine (DExD/H)-box helicase 36 (DHX36), whereas CpG-B selectively bound DExD/H-box helicase 9 (DHX9). Although the aspartate-glutamate-alanine-histidine box motif (DEAH) domain of DHX36 was essential for CpG-A binding, the domain of unknown function 1605 (DUF1605 domain) of DHX9 was required for CpG-B binding. DHX36 is associated with IFN-alpha production and IRF7 nuclear translocation in response to CpG-A, but DHX9 is important for TNF-alpha and IL-6 production and NF-kappaB activation in response to CpG-B. Knocking down DHX9 or DHX36 significantly reduced the cytokine responses of pDCs to a DNA virus but had no effect on the cytokine responses to an RNA virus. We further showed that both DHX9 and DHX36 are localized within the cytosol and are directly bound to the Toll-interleukin receptor domain of MyD88 via their helicase-associated domain 2 and DUF domains. This study demonstrates that DHX9/DHX36 represent the MyD88-dependent DNA sensors in the cytosol of pDCs and suggests a much broader role for DHX helicases in viral sensing. Show less