Risk SNP-Mediated Enhancer-Promoter Interaction Drives Colorectal Cancer through Both FADS2 and AP002754.2.

Although genome-wide association studies (GWAS) have identified more than 100 colorectal cancer risk loci, most of the biological mechanisms associated with these loci remain unclear. Here we first performed a comprehensive expression quantitative trait loci analysis in colorectal cancer tissues adjusted for multiple confounders to test the determinants of germline variants in established GWAS susceptibility loci on mRNA and long noncoding RNA (lncRNA) expression. Combining integrative functional genomic/epigenomic analyses and a large-scale population study consisting of 6,024 cases and 10,022 controls, we then prioritized rs174575 with a C>G change as a potential causal candidate for colorectal cancer at 11q12.2, as its G allele was associated with an increased risk of colorectal cancer (OR = 1.26; 95% confidence interval = 1.17-1.36; P = 2.57 × 10-9). rs174575 acted as an allele-specific enhancer to distally facilitate expression of both FADS2 and lncRNA AP002754.2 via long-range enhancer-promoter interaction loops, which were mediated by E2F1. AP002754.2 further activated a transcriptional activator that upregulated FADS2 expression. FADS2, in turn, was overexpressed in colorectal cancer tumor tissues and functioned as a potential oncogene that facilitated colorectal cancer cell proliferation and xenograft growth in vitro and in vivo by increasing the metabolism of PGE2, an oncogenic molecule involved in colorectal cancer tumorigenesis. Our findings represent a novel mechanism by which a noncoding variant can facilitate long-range genome interactions to modulate the expression of multiple genes including not only mRNA, but also lncRNA, which provides new insights into the understanding of colorectal cancer etiology. SIGNIFICANCE: This study provides an oncogenic regulatory circuit among several oncogenes including E2F1, FADS2, and AP002754.2 underlying the association of rs174575 with colorectal cancer risk, which is driven by long-range enhancer-promoter interaction loops. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/9/1804/F1.large.jpg.

Systematic Functional Interrogation of Genes in GWAS Loci Identified ATF1 as a Key Driver in Colorectal Cancer Modulated by a Promoter-Enhancer Interaction.

Genome-wide association studies (GWASs) have identified approximately 100 colorectal cancer (CRC) risk loci. However, the causal genes in these loci have not been systematically interrogated. We conducted a high-throughput RNA-interference functional screen to identify the genes essential for proliferation in the CRC risk loci of Asian populations. We found that ATF1, located in the 12q13.12 region, functions as an oncogene that facilitates cell proliferation; ATF1 has the most significant effect of the identified genes and promotes CRC xenograft growth by affecting cell apoptosis. Next, by integrating a fine-mapping analysis, a two-stage affected-control study consisting of 6,213 affected individuals and 10,388 controls, and multipronged experiments, we elucidated that two risk variants, dbSNP: rs61926301 and dbSNP: rs7959129, that located in the ATF1 promoter and first intron, respectively, facilitate a promoter-enhancer interaction, mediated by the synergy of SP1 and GATA3, to upregulate ATF1 expression, thus synergistically predisposing to CRC risk (OR = 1.77, 95% CI = 1.42-2.21, p = 3.16 × 10-7; Pmultiplicative-interaction = 1.20 × 10-22; Padditive-interaction = 6.50 × 10-3). Finally, we performed RNA-seq and ChIP-seq assays in CRC cells treated with ATF1 overexpression in order to dissect the target programs of ATF1. Results showed that ATF1 activates a subset of genes, including BRAF, NRAS, MYC, BIRC2, DAAM1, MAML2, STAT1, ID1, and NKD2, related to apoptosis, Wnt, TGF-ß, and MAPK pathways, and these effects could cooperatively increase the risk of CRC. These findings reveal the clinical potential of ATF1 in CRC development and illuminate a promoter-enhancer interaction module between the ATF1 regulatory elements dbSNP: rs61926301 and dbSNP: rs7959129, and they bring us closer to understanding the molecular drivers of cancer.

A functional variant rs1537373 in 9p21.3 region is associated with pancreatic cancer risk.

9p21.3 has been identified as an unexpected hot point in multiple diseases GWAS including cancers, and we performed a two-stage case-control studies integrating functional assay strategy to find the potential functional variants modified susceptibility to pancreatic cancer (PC). An expanded Illumina HumanExome Beadchip of PC including 943 cases and 3908 controls was used to examine 39 tagSNPs in 9p21.3 and the promising single nucleotide polymorphism (SNP) was validated in stage 2 comprising 624 cases and 1048 controls. The strongest signal was rs6475609 (Odds ratio, OR = 0.81, 95% confidence interval, CI = 0.72-0.91) maps to the long non-coding RNA ANRIL. Bioinformatics analysis revealed rs1537373 lies in the linkage disequilibrium (LD) block which the rs6475609 tagged might have potential function and was also associated with a decreased risk of PC in both stages (OR = 0.82, 95% CI = 0.75-0.90 in combined analysis). Dual luciferase reporter assay and the electrophoretic mobility shift assay (EMSA) verified rs1537373 as the best candidate causative variant for influencing the activity of enhancer through differential binding to certain transcription factor. The expression quantitative trait loci (e-QTL) analysis indicated the genotypes of rs1537373 were associated with expression of CDKN2B gene (P dominant = 6.00 × 10-4 ). In conclusion, our study provided evidence that rs1537373 in ANRIL may influence transcription factor binding and regulate CDKN2B expression, thus confer the susceptibility to PC.

Exome-wide analysis identifies three low-frequency missense variants associated with pancreatic cancer risk in Chinese populations.

Germline coding variants have not been systematically investigated for pancreatic ductal adenocarcinoma (PDAC). Here we report an exome-wide investigation using the Illumina Human Exome Beadchip with 943 PDAC cases and 3908 controls in the Chinese population, followed by two independent replicate samples including 2142 cases and 4697 controls. We identify three low-frequency missense variants associated with the PDAC risk: rs34309238 in PKN1 (OR = 1.77, 95% CI: 1.48-2.12, P = 5.35 × 10-10), rs2242241 in DOK2 (OR = 1.85, 95% CI: 1.50-2.27, P = 4.34 × 10-9), and rs183117027 in APOB (OR = 2.34, 95% CI: 1.72-3.16, P = 4.21 × 10-8). Functional analyses show that the PKN1 rs34309238 variant significantly increases the level of phosphorylated PKN1 and thus enhances PDAC cells' proliferation by phosphorylating and activating the FAK/PI3K/AKT pathway. These findings highlight the significance of coding variants in the development of PDAC and provide more insights into the prevention of this disease.

Integrative functional genomics identifies regulatory genetic variant modulating RAB31 expression and altering susceptibility to breast cancer.

Despite the successes of genome-wide association study (GWAS) in identifying breast cancer (BC) risk-associated variants, only a small fraction of the heritability can be explained. The greatest challenge in the post-GWAS is to identify causal variants and underlying mechanisms responsible for BC susceptibility. In this study, we integrated functional genomic data from ENCODE ChIP-seq, ANNOVAR, and the TRANSFAC matrix to identify potentially regulatory variants with modulating FOXA1-binding affinity across the whole genome, and then conducted a two-stage case-control study including 2164 cases and 2382 controls to investigate the associations between candidate SNPs and BC susceptibility. We identified a BC susceptibility SNP, rs6506689 G>T, with an odds ratio (OR) of 1.23 (95% confidence interval = 1.07-1.40, P = 0.003) under a dominant model in the combined study. Biological assays indicated that the germline G>T variation at rs6506689 creates a FOXA1-binding site and up-regulates the expression of RAB31, thus playing an important role in the development of BC. Our results highlight the importance of regulatory genetic variants in the development of BC by influencing TF-DNA interaction and provide critical insights to pinpoint causal genetic variants.

A Rare Missense Variant in TCF7L2 Associates with Colorectal Cancer Risk by Interacting with a GWAS-Identified Regulatory Variant in the MYC Enhancer.

Genome-wide association studies (GWAS) of colorectal cancer have identified several common susceptible variants in gene regulatory regions. However, low-frequency or rare coding risk variants have not been systematically investigated in patients with colorectal cancer from Chinese populations. In this study, we performed an exome-wide association analysis with 1,062 patients with colorectal cancer and 2,184 controls from a Chinese population. Promising associations were further replicated in two replication sets: replication stage I with 2,478 cases and 3,880 controls, and replication stage II with 3,761 cases and 4,058 controls. We identified two variants significantly associated with colorectal cancer risk: a novel rare missense variant in TCF7L2 [rs138649767, OR = 2.08, 95% confidence interval (CI): 1.69-2.57, P = 5.66 × 10-12] and a previous European GWAS-identified 3'-UTR variant in ATF1 (rs11169571, OR = 1.18, 95% CI: 1.13-1.24, P = 1.65 × 10-12). We found a significant interaction between the TCF7L2 missense variant rs138649767 and a previous GWAS-identified regulatory variant rs6983267 in the MYC enhancer (Pinteraction = 0.0002). Functional analysis of this variant revealed that TCF7L2 with rs138649767-A allele harbored the ability to activate the MYC enhancer with rs6983267-G allele and enhance colorectal cancer cell proliferation. In addition, the ATF1 rs11169571 variant significantly correlated with ATF1 expression by affecting hsa-miR-1283 and hsa-miR-520d-5p binding. Further ChIP-seq and gene coexpression analyses showed that oncogenes NRAS and BRAF were activated by ATF1 in colorectal cancer. These results widen our understanding of the molecular basis of colorectal cancer risk and provide insight into pathways that might be targeted to prevent colorectal cancer.Significance: Exome-wide association analysis identifies a rare missense variant in TCF7L2 and a common regulatory variant in ATF1 as susceptibility factors of colorectal cancer.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/17/5164/F1.large.jpg Cancer Res; 78(17); 5164-72. ©2018 AACR.

Educational and Behavioral Counseling in a Methadone Maintenance Treatment Program in China: A Randomized Controlled Trial.

INTRODUCTION: Methadone maintenance treatment (MMT) programs have been rapidly scaled up nationwide in China in recent years, and psychosocial intervention measures, including counseling, were recommended for improving the outcomes of MMT. However, the effectiveness of counseling in MMT programs remains controversial. This study investigated the efficacy of educational and behavioral counseling (EBC) mode in an MMT program in China. METHODS: A total of 125 eligible participants were randomized to EBC or a control group. Patients in the EBC group received weekly, manual-guided, group educational counseling for 8 weeks and individual behavioral counseling for the next 8 weeks. Patients in the control group received standard methadone maintenance treatment as usual (TAU). RESULTS: During the 16-week trial, the EBC group showed better treatment attendance (P = 0.022) and a greater increase in knowledge regarding heroin addiction (P = 0.001) and MMT (P = 0.005) than did the TAU group. Between the two groups, there were no significant differences regarding drug abstinence and reduction of risky behaviors. CONCLUSION: EBC affiliated with MMT improved patients' cognition and adherence to treatment, facilitating their successful recovery. CLINICAL TRIAL REGISTRATION: ChiCTR-IOR-15006673: http://www.chictr.org.cn.

Integrative expression quantitative trait locus-based analysis of colorectal cancer identified a functional polymorphism regulating SLC22A5 expression.

Multiple single nucleotide polymorphisms (SNPs) have been found to be highly correlated with colorectal cancer (CRC) risk. However, the variants identified thus far only explain a small part of the cases, suggesting the existence of many uncharacterised genetic determinants. In this study, using the multilevel 'omics' data provided in The Cancer Genome Atlas, we systematically performed expression quantitative trait locus (eQTL) analysis for CRC and identified nine SNPs with significant effects on mRNA expression (correlation |r| > 0.3 and FDR < 0.01). Then we conducted a two-stage case-control study consisting of 1528 cases and 1528 controls to examine the associations between candidate SNPs and CRC risk. We found that rs27437 in SLC22A5 was significantly correlated with CRC risk in both stages and the combined study (additive model, OR = 1.31, 95%CI = 1.17-1.47, P = 1.97 × 10-6). eQTL analysis showed that rs27437 GG and GA genotypes were associated with lower expression of SLC22A5 compared with the AA genotype. Dual-luciferase reporter assays confirmed that the G risk allele could decrease the expression of luciferase. SLC22A5 was significantly decreased in CRC tumour tissues compared with adjacent normal tissues, indicating that SLC22A5 may play important roles in CRC, and rs27437 in SLC22A5 might serve as a novel biomarker for early detection and prevention of CRC.

Exome-wide analyses identify low-frequency variant in CYP26B1 and additional coding variants associated with esophageal squamous cell carcinoma.

Genome-wide association studies have identified common variants associated with risk of esophageal squamous cell carcinoma (ESCC). However, these common variants cannot explain all heritability of ESCC. Here we report an exome-wide interrogation of 3,714 individuals with ESCC and 3,880 controls for low-frequency susceptibility loci, with two independent replication samples comprising 7,002 cases and 8,757 controls. We found six new susceptibility loci in CCHCR1, TCN2, TNXB, LTA, CYP26B1 and FASN (P = 7.77 × 10-24 to P = 1.49 × 10-11), and three low-frequency variants had relatively high effect size (odds ratio > 1.5). Individuals with the rs138478634-GA genotype had significantly lower levels of serum all-trans retinoic acid, an anticancer nutrient, than those with the rs138478634-GG genotype (P = 0.0004), most likely due to an enhanced capacity of variant CYP26B1 to catabolize this agent. These findings emphasize the important role of rare coding variants in the development of ESCC.

A low-frequency variant in SMAD7 modulates TGF-ß signaling and confers risk for colorectal cancer in Chinese population.

The TGF-ß pathway plays an essential role in regulating cell proliferation and differentiation. GWASs and candidate approaches have identified a battery of genetic variants in the TGF-ß pathway contributing to colorectal cancer (CRC). However, most of the significant variants are common variants and their functions remain ambiguous. To identify causal variants with low-frequency in the TGF-ß pathway contributing to CRC susceptibility in Chinese population, we performed targeted sequencing of 12 key genes in TGF-ß signaling in CRC patients followed by a two-stage case-control study with a total of 5109 cases and 5169 controls. Bioinformatic annotations and biochemical experiments were applied to reveal the potential functions of significant variants. Seven low-frequency genetic variants were captured through targeted sequencing. The two stage association studies showed that missense variant rs3764482 (c. 83C>T; p. S28F) in the gene SMAD7 was consistently and significantly associated with CRC risk. Compared with the wild type, the ORs for variant allele were 1.37 (95%CI: 1.10-1.70, P = 0.005), 1.55 (95%CI: 1.30-1.86, P = 1.15 × 106 ), and 1.48 (1.29-1.70, P = 2.44 × 10;8 ) in stage 1, stage 2, and the combined analyses, respectively. Functional annotations revealed that the minor allele T of rs3764482 was more effective than the major allele C in blocking the TGF-ß signaling and inhibiting the phosphorylation of receptor-regulated SMADs (R-SMADs). In conclusion, low-frequency coding variant rs3764482 in SMAD7 is associated with CRC risk in Chinese population. The rs3764482 variant may block the TGF-ß signaling via impeding the activation of downstream genes, leading to cancer cell proliferation, thus contributing to CRC pathogenesis.

A functional polymorphism located at transcription factor binding sites, rs6695837 near LAMC1 gene, confers risk of colorectal cancer in Chinese populations.

Genome-wide association studies (GWASs) have identified multiple single nucleotide polymorphisms (SNPs) associated with colorectal cancer (CRC) susceptibility. However, the elucidation of causal SNPs and the biological mechanisms behind are still limited. In this study, we initially performed systematic bioinformatics analyses on CRC GWAS-identified loci to seek for potential functional SNPs located at transcription factor binding sites (TFBSs), and then a two-stage case-control study comprised of 1353 cases and 1448 controls of Chinese populations and functional analyses were conducted. As a result, only one SNP rs6695837 out of the nine candidate SNPs survived after two-stage analyses by Bonferroni correction. In combined analyses, rs6695837 exhibited significant associations with CRC risk (TT: CC, odds ratio (OR) = 1.31, 95% confidence interval (CI) = 1.06-1.63; dominant model, OR = 1.21, 95% CI = 1.03-1.43; additive model, OR = 1.15, 95% CI = 1.03-1.28). Functional annotations by RegulomeDB and rSNPBase indicated its biological role and dual-luciferase reporter assays revealed a significant increase in luciferase expression for the reconstructed plasmid with rs6695837T allele, compared with the one with C allele (PSW480 = 0.0002, PLovo = 0.0003). Further gene expression analyses demonstrated significantly higher expression of LAMC1 gene in CRC tumor tissues than that in adjacent non-cancerous tissues (P = 0.0004). These findings strongly suggest that the functional SNP located at TFBSs, rs6695837 might contribute to CRC susceptibility, and the exact biological mechanism awaits further research.

[Effect of Bushen Huoxue Recipe on Paracrine Gene Expression Profiling of Uterine Natural Killer Cells and Uterine Stromal Cells].

Objective To observe the effect of Bushen Huoxue Recipe (BHR) on paracrine gene expression profiling of uterine natural killer cells (uNK cells) and uterine stromal cells. Methods Human stromal cells were extracted from proliferative phase endometrium of child-bearing age females, which were then divided into the blank group, the control group, and the BHR group. DMEM/F12 was added in cells of the BHR group to dilute into final concentration of 2 mg/mL herbal liquor. Equal volume of DMEM/ F12 was added to cells in the normal group and the control group. Cells in the control group and the BHR group were cultured for 24 h, with 20% serum-free DMEM plus 80% uNK cell secretion extracting solution added. Then they were cultured in 5% CΟ2 at 37 °C for 6 h. Total RNAs were extracted after culture. The gene expression profile of stromal cells was detected using gene chip technology. At the same time mR- NA and protein expressions of chemokine (C-X-C motif) ligand 1 (CXCL1), intercellular cell adhesion molecule-1 (ICAM-1) , IL-8, and leukocyte inhibitor factor (LIF) were screened and detected using qRT- PCR and ELISA. Results Compared with the blank group, profiles of differentiated genes with 4-fold in- crease (a total of 63 genes) were basically agreeable in the control group and the BHR group. Compared with the control group, IL-15 receptor alpha (IL-15RA) was up-regulated by 1. 27 times, vascular endotheli- ai growth factor (VEGF) up-regulated by 1. 55 times, LIF up-regulated by 1. 45 times, IL-8 up-regulated by 1. 10 times, IL-11 up-regulated by 1. 23 times, transforming growth factor-ß (TGF-ß) up-regulated by 1. 40 times, epidermal growth factor (EGF) up-regulated by 1. 10 times, chemokine (C-C motif) ligand 8 (CCL8) up-regulated by 1.13 times, transporter 1 (TAP1 ) up-regulated by 1. 02 times, chemokine (C-X-C motif) receptor 2 (CXCR2) up-regulated by 1. 22 times, ICAM-1 up-regulated by 1. 15 times (P <0. 05) in the BHR group. Conclusion uNK paracrine played an important role in elevating endometrial receptivity and embry- o implantation, and BHR could improve and elevate the function of this paracrine system.

A functional variant rs4442975 modulating FOXA1-binding affinity does not influence the risk or progression of breast cancer in Chinese Han population.

The DNA-binding protein FOXA1 has been shown to regulate nearly all estrogen receptor-chromatin interactions, thereby influencing target gene expression levels in breast cancer (BC) cells. Recently, the rs4442975 T-allele, which disrupts the recruitment of FOXA1 and interacts with the IGFBP5 promoter, was associated to BC susceptibility in a European population. We conducted a hospital-based case-control study that included 1227 cases and 1285 controls to explore the potential association between rs4442975 and BC risk in Chinese Han population, and the effect of this SNP on BC progression was also observed in cases. No significant associations between rs4442975 and BC risk were observed under any genetic models, with an odds ratio of 0.96 (95% confidence interval = 0.81-1.15) under the additive model. When stratified based on estrogen or progesterone receptor expression, smoking or drinking habits, or menopausal status, similar negative associations were observed for all subgroups. No significant associations were observed between rs4442975 and traditional progression factors such as tumor size, nodal status, distant metastasis, or TNM staging. These results reveal that rs4442975 may not confer a risk of BC occurrence or progression in the Chinese Han population, which indicates a distinct association related to genetic heterogeneity across ethnic populations.

A single nucleotide polymorphism in the 3'-UTR of STAT3 regulates its expression and reduces risk of pancreatic cancer in a Chinese population.

Pancreatic cancer (PC) is one of the deadliest solid malignancies carrying a gloomy 5-year survival rate less than 5%. The signal transducer and activator of transcription 3 (STAT3) is a common transcriptional regulator, whose aberrant expression has been widely found in human cancers, including PC. Our current study aimed to illustrate the roles of common variants, in the three prime untranslated region (3'UTR) of STAT3, in modifying the risk of PC through two-stage case-control studies integrating biological experiments. We first explored the associations between two common variants (rs1053004 and rs1053005) and PC risk in 774 PC cases and 777 controls. Only rs1053004 T > C showed a significant association with a reduced risk of PC with an odds ratio (OR) and 95% confidence interval (CI) of 0.85 (0.74-0.98). Then we attempted to validate the association in another 940 cases and 1398 controls, and the significant association persisted with OR (95%CI) of 0.86 (0.76-0.97). Dual luciferase reporter gene assays indicated that C allele conferred a higher expression of STAT3 in three PC cell lines including Panc-1 (P = 3.0 × 10-3), BxPC-3 (P = 6.7 × 10-5) and SW1990 (P = 4.0 × 10-3). In conclusion, the current study provided evidence that rs1053004 T > C in 3'UTR of STAT3 may decrease the risk of PC through up-regulating the gene expression.

Association between bilirubin and risk of Non-Alcoholic Fatty Liver Disease based on a prospective cohort study.

The study aimed to assess the association between total, direct, and indirect bilirubin and nonalcoholic fatty live disease (NAFLD) risk given its high prevalence and serious clinical prognosis. Among 27,009 subjects who participated in a healthy screening program from the Dongfeng-Tongji cohort study in 2008, 8189 eligible subjects (aged 35-86 years; males, 43.95%) were ultimately enrolled. The incidence rates of NAFLD in 2013 were compared with respect to baseline bilirubin levels among subjects free of NAFLD, and the effect sizes were estimated by logistic regression analysis. During 5 years follow-up, we observed 1956 cases of newly developed NAFLD with the overall incidence of 23.88%. Direct bilirubin was presented to inversely associate with NAFLD risk. Compared with quartile 1 of direct bilirubin, the multivariable-adjusted ORs (95% CIs) for NAFLD of quartile 2 to 4 were 1.104 (0.867-1.187), 0.843 (0.719-0.989), and 0.768 (0.652-0.905), respectively, P for trend 0.002). Similarly, inverse effects of direct bilirubin on NAFLD incidence were also observed when stratified by sex and BMI. However, no significant associations were found between total, and indirect bilirubin and NAFLD risk. Direct bilirubin reduced NAFLD risk independent of possible confounders among middle-aged and elderly Chinese population, probably based on the endogenous antioxidation of bilirubin.

Genetic variants in the regulatory region of SLC10A1 are not associated with the risk of hepatitis B virus infection and clearance.

The Na/taurocholate cotransporter NTCP (encoded by SLC10A1) was identified as a cellular entry receptor for the human hepatitis B virus (HBV), advancing our understanding of the molecular mechanism of HBV infection. An alternative hypothesis was put forward that regulatory variants in SLC10A1 might play an important role in HBV susceptibility by potentially influencing expression levels of NTCP. The three regulatory SNPs (rs8011311, rs7154439, rs111409076) were genotyped in 1023 HBV-persistent carriers, 735 subjects with HBV natural clearance and 732 HBV marker-negative subjects in a Han Chinese population. Real-time reverse transcription PCR analysis and luciferase assays have been performed to dissect the potential functionality. In logistic regression analysis, when subjects with HBV natural clearance were compared with HBV marker-negative subjects, no significant associations with the risk of HBV infection were observed for any of the three SNPs after adjusting for age, sex, smoking status and alcohol consumption (P>0.05). Similar negative results were also found for the three SNPs when HBV-persistent carriers were compared with HBV marker-negative subjects. Likewise, no significant associations with the risk of HBV clearance were observed when HBV-persistent carriers were compared with subjects with HBV natural clearance (P>0.05). Quantitative RT/PCR showed no significant difference in NTCP expression levels in normal liver tissue amongst individuals with different rs111409076 genotypes (P=0.317 for the general linear model). Moreover, no evident effect of the SLC10A1 rs111409076 AACA/- polymorphism on transcriptional activity was found by luciferase assay in either HepG2 (P=0.161) or Hep3b (P=0.129) cell lines. The present study indicated that the common variants in the regulatory region of SLC10A1 may not influence the expression of NTCP at the level of transcriptional regulation, and ultimately may not be associated with HBV susceptibility in this Chinese population.

The contribution of serum hepatitis B virus load in the carcinogenesis and prognosis of hepatocellular carcinoma: evidence from two meta-analyses.

BACKGROUND AND AIM: The meta-analysis aimed to quantify and summarize the contribution of serum hepatitis B virus (HBV) DNA load in the carcinogenesis and prognosis of hepatocellular carcinoma (HCC). RESULTS: Nine independent studies with a total of 1162 cases and 9365 participants on risk of HCC and seventeen studies with 1342 cases and 2891 participants on recurrence of HCC were finally included. The non-liner dose-response association between HBV DNA level and HCC risk was observed, with P value equal to 0.02 for linear test. Compared with 2 log10copies/ml HBV DNA level carriers, the summary relative risk of HCC were 1.65(95% CI: 0.94-2.92) for 4.5 log10copies/ml, 2.20(95% CI: 1.00-4.85) for 5.5 log10copies/ml, 3.06(95% CI: 1.11-8.44) for 6.5 log10copies/ml. Moreover, individuals with high viral load (HBV DNA levels > 105copies/ml) presented significant association with increased risk of HCC recurrence, with the pooled RR of 1.69 (95% CI: 1.49-1.92). MATERIALS AND METHODS: Pertinent studies were identified by searching PubMed, Embase and ISI Web of science databases up to January 2016 and by reviewing the references of retrieved articles. The dose-response meta-analysis was precisely performed to calculate the summary relative risks (RRs) by quantizing the association between HBV load and risk of HCC. Besides, the contribution of HBV load on recurrence of HCC was further clarified by general meta-analysis. CONCLUSIONS: These findings indicated a non-linear dose-response relationship between serum HBV DNA level and risk of HCC, and confirmed the significant contribution of serum HBV DNA level in the prognosis of HCC.

Common genetic variants of GPC1 gene reduce risk of biliary atresia in a Chinese population.

BACKGROUND: Biliary atresia (BA) is a major neonatal cholestatic disease and main indication for pediatric liver transplantation in the world. Recently, GPC1 has been implicated as a risk gene for BA by genetic studies and follow-up functional experiments on zebrafish. METHODS: Two common genetic variants of GPC1, rs2292832 and rs3828336, were selected systematically through 'SNPinfo', and were examined using TaqMan Genotyping Assays for association studies in a Chinese population containing 134 cases and 618 controls. RESULTS: Of the two single nucleotide polymorphisms (SNPs), we found a significantly decreased BA risk associated with rs2292832 (additive model: OR=0.638, 95% CI: 0.467-0.873, P=0.005), and a marginal effect for rs3828336 (heterozygous model: OR=0.564, 95% CI: 0.312-1.020, P=0.058). The haplotype analysis indicated that either Crs2292832-Crs3828336&Trs3828336 or Trs2292832-Trs3828336 conferred a protective effect from BA (OR=0.569, 95% CI=0.414-0.783, P<0.001; OR=0.528, 95% CI: 0.301-0.926, P=0.026). Moreover, bioinformatics analysis suggested that rs2292832 altered GPC1 expression via effect on transcription-factor-binding sites (TFBS) of upstream binding transcription factor (UBTF), as a regulatory DNA variation in Deoxyribonuclease I (DNase I) hypersensitive sites (DHSs). CONCLUSION: Common variants of GPC1 gene were genetically involved in BA risk.

Nighttime sleep duration and risk of nonalcoholic fatty liver disease: the Dongfeng-Tongji prospective study.

BACKGROUND: To examine the association between self-reported nighttime sleep duration and nonalcoholic fatty liver disease (NAFLD) risk by comparing the incidence rates of NAFLD among healthy subjects with different sleep duration during the 5 years follow-up. METHODS: 8965 eligible NAFLD-free subjects with a mean age of 61.6 years (males, 43.4%) from Dongfeng-Tongji cohort study at baseline were enrolled in the study. Logistic regression analysis was used to estimate the association between sleep duration and incident NAFLD with potential confounders adjusted. Sleep duration was categorized into five groups: <6 h, 6-7 h, 7-8 h, 8-9 h, ≥9 h. RESULT: During the 5-years of follow-up, a total of 2,197 participants were newly diagnosed as NAFLD. Compared with those reported 7-8 h per day of nighttime sleep, the multivariable-adjusted odds ratio (95% confidence intervals) were 1.21 (1.07-1.38) for those who sleep 8-9 h/day, and 1.31 (1.13-1.52) for those who sleep over 9 h/day. However, no significant association was found with short nightly sleep duration (<7 h/day). CONCLUSION: Long nighttime sleep duration was associated with a modestly increased risk of NAFLD in a middle-aged and elderly Chinese population. Key messages Long nighttime sleep duration was associated with a modestly increased risk of NAFLD in a middle-aged and elderly Chinese population. The effect of long nighttime sleep on the risk of incident NAFLD was attenuated greatly by body mass index (BMI) in men.

Identification of a functional variant for colorectal cancer risk mapping to chromosome 5q31.1.

Genome-wide association studies (GWASs) have established chromosome 5q31.1 as a risk locus for colorectal cancer (CRC). We previously identified a potentially regulatory single nucleotide polymorphism (SNP) rs17716310 within 5q31.1. Now, we extended our study with another independent Chinese population, functional assays and analyses of TCGA (The Cancer Genome Atlas) data. Significant associations between rs17716310 and CRC risk were found in Present Study including 1075 CRC cases and 1999 controls (additive model: OR = 1.149, 95% CI = 1.027-1.286, P = 0.016), and in Combined Study including 1766 cases and 2708 controls (additive model: OR = 1.145, 95% CI = 1.045-1.254, P = 0.004). Dual luciferase reporter gene assays indicated that the variant C allele obviously increased transcriptional activity. Using TCGA datasets, we indicated rs17716310 as a cis expression quantitative trait locus (eQTL) for the gene SMAD5, whose expression was significantly higher in CRC tissues. These findings suggested that the functional polymorphism rs17716310 A > C might be a genetic modifier for CRC, promoting the expression of SMAD5 that belonged to the transforming growth factor beta (TGF-ß) signaling pathway.