PPM1H is down-regulated by ATF6 and dephosphorylates p-RPS6KB1 to inhibit progression of hepatocellular carcinoma.

We have shown previously that polymorphism of activating transcription factor 6 (ATF6) is associated with susceptibility to hepatocellular carcinoma (HCC). Therefore, genes down-regulated by ATF6 might play a tumor-suppressing role. In the present study, we identified that expression of protein phosphatase magnesium- or manganous-dependent 1H (PPM1H) mRNA and protein can be inhibited by ATF6 in hepatoma cells and mice with liver Atf6 knockdown. Tumor tissues from 134 HCC patients were analyzed by immunohistochemistry, and PPM1H exhibited higher expression levels in adjacent para-cancer tissues than in HCC tissues. Therefore, patients with higher expression of PPM1H had a better prognosis. PPM1H inhibited proliferation, migration, and invasion of hepatoma cells. In addition, PPM1H inhibited induced HCC nodule formation as well as tumor xenograft growth in diethylnitrosamine/CCl4-induced HCC mouse model and nude mouse tumorigenicity assay, respectively. A 3D model of PPM1H was obtained by homology multi-template modeling, and ribosomal protein S6 kinase B1 (RPS6KB1) in the bone morphogenetic protein (BMP)/transforming growth factor ß (TGF-ß) pathway was screened out as the potential substrate of PPM1H by Rosetta. PPM1H could directly dephosphorylate p-RPS6KB1. To conclude, we discovered RPS6KB1 as a new PPM1H dephosphorylation substrate. PPM1H exhibited a suppressive effect on HCC progression by dephosphorylating p-RPS6KB1.

Activating transcription factor 6 regulates cystathionine to increase autophagy and restore memory in Alzheimer' s disease model mice.

Endoplasmic reticulum stress (ER stress) plays a crucial role in the process of Alzheimer's disease (AD). Activating transcription factor 6 (ATF6) is a crucial sensor of ER stress. In AD patients, the homeostasis of the endogenous signal H2S produced by cystathionine γ-lyase (CTH) is in disbalance. However, the role of ATF6 and CTH in AD is rarely reported. Herein, we found that ATF6 and CTH were reduced in AD patients and APP/PS1 mice by immunohistochemistry and western blots. In LN229 and U87 MG cells, knockdown of ATF6 attenuated CTH expression, whereas overexpression of ATF6 resulted in upregulation of CTH. Brain-specific ATF6 knockout mice expressed significantly down-regulated CTH in the hippocampus and cortex compared to wild-type mice. Mechanistically, ATF6 and CTH increased H2S generation and autophagy-related proteins. Further we observed that CTH promoted the sulfhydration of αSNAP. This is probably to be the specific mechanism by which AFT6 promotes autophagy. Through in vivo studies, we found that αSNAP sulfhydration expression was significantly lower in ATF6 knockout mice than in wild-type mice. Decreased ATF6 impaired spatial memory retention, while addition of CTH rescued memory loss. Together, we demonstrate that ATF6 positively regulates the expression of CTH, which is closely related to the rescue of AD. Targeting the ATF6/CTH signal pathway may provide a new strategy for the treatment of AD.

ADAR1 Stimulation by IFN-α Downregulates the Expression of MAVS via RNA Editing to Regulate the Anti-HBV Response.

The partial response of chronic hepatitis B virus (CHB) patients to interferon-α (IFN-α) therapy remains elusive, which requires a better understanding of the involved molecular mechanism. In our study, bioinformatics analysis was applied to relate IFN-α regulated candidate genes and RNA editing sites by RNA sequencing. Mitochondrial antiviral signaling protein (MAVS) antiviral effect was confirmed in HepG2.2.15 cells and in two mouse models. The associations between polymorphisms in MAVS gene and response to IFN-α therapy were confirmed in CHB patients. We found that IFN-α downregulates MAVS via RNA editing that was mediated by adenosine deaminase acting on RNA (ADAR1). ADAR1 inhibited MAVS expression via a human antigen R (HuR)-mediated post-transcriptional regulation. MAVS exerted an antiviral activity and reduced the level of hepatitis B virus (HBV) markers in vitro and in vivo. IFN-α antiviral effects were significantly enhanced by MAVS co-transfection. Hepatitis B core protein (HBc) interacted with SP1 to inhibit the promoter activity of MAVS that regulates its expression. CHB patients with a rs3746662A allele had higher MAVS expression and thus were more responsive to IFN-α treatment. In this work, we demonstrated that the decrease of MAVS expression is mediated by the IFN-α-ADAR1 axis. This study also highlighted the potential for the clinical application of MAVS in combination with IFN-α for the treatment of HBV infection.

HBV suppresses thapsigargin-induced apoptosis via inhibiting CHOP expression in hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) accounts for a proportion of cancer-associated mortalities worldwide. Hepatitis B virus (HBV) infection is a major cause of HCC in China. Thapsigargin (TG) is a potential antitumor prodrug, eliciting endoplasmic reticulum (ER) stress via the inhibition of the ER calcium pump, effectively inducing apoptosis. The present study therefore examined the role of HBV in TG-induced apoptosis using two HCC cell lines, HBV positive HepG2.2.15 and HBV negative HepG2. When these two cell lines were treated with TG, HepG2.2.15 was less susceptible to apoptosis than HepG2. This phenomenon was confirmed by an MTT assay and Annexin V-FITC/propidium iodide staining. Reverse transcription quantitative polymerase chain reaction and western blotting were used to detect the expression levels of genes in the ER stress pathway subsequent to treatment with TG. Notably, the mRNA and protein levels of the apoptosis factor DNA damage inducible transcript 3 (CHOP) increased significantly in the HepG2 cells compared with the HepG2.2.15 cells. Additionally, the HepG2.2.15 cells treated with interferon-α exhibited higher levels of CHOP compared with the untreated cells. The overexpression or knockdown of CHOP microRNA in HepG2.2.15 or HepG2 cells may reduce the difference in apoptosis status between the two cell lines. These results suggest that HBV may inhibit the apoptosis induced by ER stress. These findings may be useful in the development of selective therapies for patients with HBV-positive tumors.

IRG1 increases MHC class I level in macrophages through STAT-TAP1 axis depending on NADPH oxidase mediated reactive oxygen species.

The major histocompatibility complex (MHC) is the connection between innate immunity and acquired immune system. Recently, many studies reported that the immunoresponsive gene 1 (IRG1) play an important role on innate immunity including reactive oxygen species (ROS), antiviral effect and expression of inflammatory factors. However, the function of IRG1 in antigen presenting remains unclear. In this study, we found that overexpressed-IRG1 promoted MHC I level instead of MHC II in macrophages membrane. Besides, IRG1 increased expression of some transporter proteins associated with antigen processing involving TAP1, PSMB9 depending on ROS. By detecting the activation of glucose-6-phosphate dehydrogenase (G6PD), we confirmed that IRG1 could increase ROS level by promoting pentose phosphate pathway (PPP). DPI, an inhibitor of NADPH oxidase (NOX), also significant attenuated TAP1 and MHC I level in IRG1-overexpressed macrophages. Finally, results showed that phosphorylation of STAT1/3 involved in IRG1-mediated TAP1 and MHC I expression. In conclusion, IRG1 increased MHC class I level in macrophages through STAT1/3-TAP1 axis depending on PPP and NOX mediated ROS.

Erratum: HBV suppresses thapsigargin-induced apoptosis via inhibiting CHOP expression in hepatocellular carcinoma cells.

[This corrects the article DOI: 10.3892/ol.2017.6666.].

Polymorphisms in IRG1 gene associated with immune responses to hepatitis B vaccination in a Chinese Han population and function to restrain the HBV life cycle.

Vaccination against the hepatitis B virus (HBV) is extensively used as an effective method to prevent HBV infection. However, nearly 10% of healthy adults fail to produce a protective level of antibodies against the hepatitis B vaccine, and multiple genetic variants are known to affect the immune response to the hepatitis B vaccine. The aim of the present study was to investigate the association between polymorphisms in immunoresponsive gene 1 (IRG1) gene and the immune response to hepatitis B vaccination in a Chinese Han population. Four single nucleotide polymorphisms (SNPs) located in the IRG1 gene were genotyped in 1230 high-responders and 451 non-responders to hepatitis B vaccination. The SNPs rs17470171 and rs17385627 were associated with the immune response to hepatitis B vaccination (P = 0.014 and 0.029, respectively). In addition, the haplotypes G-A-A-A (rs614171-rs17470171-rs9530614-rs17385627, P = 0.0042, OR = 0.68) and A-A (rs17470171-rs17385627, P = 0.0065, OR = 0.72) exerted a protective role in the immune response to hepatitis B vaccination. Allele 'A' of rs17470171 and allele 'A' of rs17385627 show higher levels of expression for the IRG1 gene compared with allele 'C' of rs17470171 and allele 'T' of rs17385627 as demonstrated by luciferase reporter and overexpression assays. In addition, we observed that IRG1 inhibited the HBV life cycle and that IRG1 rs17385627 allele 'A' was more effective than rs17385627 allele 'T' at eliminating HBV in HepG2.2.15 cells. These findings suggest that polymorphisms in the IRG1 gene are associated with the immune response to hepatitis B vaccination. The antiviral effect of IRG1 was confirmed using HBV infection cell models.

Genetic variation in STAT4 predicts response to interferon-α therapy for hepatitis B e antigen-positive chronic hepatitis B.

UNLABELLED: Interferon (IFN)-α is a first-line therapy for chronic hepatitis B (CHB) patients but only initiates a response in a minority of patients. A genetic variant, rs7574865 in STAT4, was recently reported to be associated with risk of developing CHB and hepatitis B virus-related hepatocellular carcinoma. We aimed to determine whether this variant is associated with the response to IFNα treatment for hepatitis B e antigen (HBeAg)-positive CHB patients. We studied 466 HBeAg-positive CHB patients who received either IFNα-2b (n = 224) or pegylated IFNα-2a (n = 242) therapy for 48 weeks and were followed for an additional 24 weeks. The rate of sustained virologic response (SVR), defined as HBeAg seroconversion along with hepatitis B virus DNA level <2000 copies/mL at week 72, was compared among patients with different genotypes of rs7574865. After 48 weeks of treatment and 24 weeks off treatment, the SVR rates in the IFNα-2b and pegylated IFNα-2a therapy groups were 30.4% and 28.9%, respectively. Compared to the rs7574865 GT/TT genotype, the GG genotype (a risk factor of CHB and hepatitis B virus-related hepatocellular carcinoma) was significantly associated with a reduced SVR rate in both patients who received IFNα-2b therapy (21.1% versus 37.2%, P = 0.01) and those who received pegylated IFNα-2a therapy (18.0% versus 41.2%, P = 9.74 × 10(-5) ). In joint analysis of the 466 patients, the GG genotype was associated with an approximately half SVR rate compared to the GT/TT genotype (19.3% versus 39.1%, P = 4.15 × 10(-6) ). A multivariate logistic regression model including rs7574865 and clinical variables showed that rs7574865 was the most significant factor for the prediction of SVR. CONCLUSION: STAT4 rs7574865 is a reliable predictor of response to IFNα therapy for HBeAg-positive CHB patients and may be used for optimizing the treatment of CHB.

Genetic variations in STAT4,C2,HLA-DRB1 and HLA-DQ associated with risk of hepatitis B virus-related liver cirrhosis.

Recent genome-wide associated studies (GWASs) have revealed several common loci associated with the risk of hepatitis B virus (HBV)- or hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC). We selected 15 single nucleotide polymorphisms (SNPs) identified through GWASs on HBV- or HCV-related HCC, and genotyped them in two independent Chinese cohorts of chronic HBV carriers, including 712 LC cases and 2601 controls. The association of each SNP with the risk of HBV-related LC was assessed by meta-analysis of the two cohorts. Of the 12 SNPs reported in HBV-related HCC GWASs, five SNPs (rs7574865 in STAT4, rs9267673 near C2, rs2647073 and rs3997872 near HLA-DRB1 and rs9275319 near HLA-DQ), were found to be significantly associated with the risk of HBV-related LC (rs7574865: P = 1.79 × 10(-2), OR = 1.17, 95% CI = 1.03-1.34; rs9267673: P = 4.91 × 10(-4), OR = 1.37, 95% CI = 1.15-1.63; rs2647073: P = 3.53 × 10(-5), OR = 1.63, 95% CI = 1.29-2.06; rs3997872: P = 4.22 × 10(-4), OR = 1.86, 95% CI = 1.32-2.62; rs9275319: P = 1.30 × 10(-2), OR = 1.32, 95% CI = 1.06-1.64). However, among the three SNPs associated with the risk of HCV-related HCC in previous GWASs, none of them showed significant association with the risk of HBV-related LC. Our results suggested that genetic variants associated with HBV-related hepatocarcinogenesis may already play an important role in the progression from CHB to LC.

Genetic variants in five novel loci including CFB and CD40 predispose to chronic hepatitis B.

UNLABELLED: Hepatitis B virus affects more than 2 billion people worldwide, 350 million of which have developed chronic hepatitis B (CHB). The genetic factors that confer CHB risk are still largely unknown. We sought to identify genetic variants for CHB susceptibility in the Chinese population. We undertook a genome-wide association study (GWAS) in 2,514 CHB cases and 1,130 normal controls from eastern China. We replicated 33 of the most promising signals and eight previously reported CHB risk loci through a two-stage validation totaling 6,600 CHB cases and 8,127 controls in four independent populations, of which two populations were recruited from eastern China, one from northern China and one from southern China. The joint analyses of 9,114 CHB cases and 9,257 controls revealed significant association of CHB risk with five novel loci. Four loci are located in the human leukocyte antigen (HLA) region at 6p21.3, including two nonsynonymous variants (rs12614 [R32W] in complement factor B [CFB], Pmeta =1.28 × 10(-34) ; and rs422951 [T320A] in NOTCH4, Pmeta = 5.33 × 10(-16) ); one synonymous variant (rs378352 in HLA-DOA corresponding to HLA-DOA*010101, Pmeta = 1.04 × 10(-23) ); and one noncoding variant (rs2853953 near HLA-C, Pmeta = 5.06 × 10(-20) ). Another locus is located at 20q13.1 (rs1883832 in the Kozak sequence of CD40, Pmeta = 2.95 × 10(-15) ). Additionally, we validated seven of eight previously reported CHB susceptibility loci (rs3130542 at HLA-C, rs1419881 at TCF19, rs652888 at EHMT2, rs2856718 at HLA-DQB1, rs7453920 at HLA-DQB2, rs3077 at HLA-DPA1, and rs9277535 at HLA-DPA2, which are all located in the HLA region, 9.84 × 10(-71) ≤ Pmeta ≤ 9.92 × 10(-7) ). CONCLUSION: Our GWAS identified five novel susceptibility loci for CHB. These findings improve the understanding of CHB etiology and may provide new targets for prevention and treatment of this disease.

A genome-wide association study identifies polymorphisms in the HLA-DR region associated with non-response to hepatitis B vaccination in Chinese Han populations.

Vaccination against hepatitis B virus is an effective and routine practice that can prevent infection. However, 5-10% of healthy adults fail to produce protective levels of antibody against the hepatitis B vaccination. It has been reported that host genetic variants might affect the immune response to hepatitis B vaccination. Here, we reported a genome-wide association study in a Chinese Han population consisting of 108 primary high-responders and 77 booster non-responders to hepatitis B vaccination using the Illumina HumanOmniExpress Beadchip. We identified 21 SNPs at 6p21.32 were significantly associated with non-response to booster hepatitis B vaccination (P-value <1 × 10(-6)). The most significant SNP in the region was rs477515, located ∼12 kb upstream of the HLA-DRB1 gene. Its P-value (4.81 × 10(-8)) exceeded the Bonferroni-corrected genome-wide significance threshold. Four tagging SNPs (rs477515, rs28366298, rs3763316 and rs13204672) that capture genetic information of these 21 SNPs were validated in three additional Chinese Han populations, consisting of 1336 primary high-responders and 420 primary non-responders. The four SNPs continued to show significant associations with non-response to hepatitis B vaccination (P-combined = 3.98 × 10(-13)- 1.42 × 10(-8)). Further analysis showed that the rs477515 was independently associated with non-response to hepatitis B vaccination with correction for other three SNPs in our GWAS and the known hepatitis B vaccine immunity associated SNP in previous GWAS. Our findings suggest that the rs477515 was an independent marker associated with non-response to hepatitis B vaccination and HLA-DR region might be a critical susceptibility locus of hepatitis B vaccine-induced immunity.

A functional polymorphism in ADAR1 gene affects HBsAg seroclearance both spontaneously and interferon induced.

BACKGROUND & AIMS: Our previous study found that rs4845384 in ADAR1 gene to be associated with HBeAg seroconversion. However, the effect of rs4845384 on HBsAg seroclearance is unknown. To assess the relationship between rs4845384 and HBsAg seroclearance. METHODS: Two independent case-control studies were conducted to test whether rs4845384 in ADAR1 was associated with HBsAg clearance. Reporter gene assays and quantitative PCR experiments were also carried out to verify the functional significances of this polymorphism. RESULTS AND CONCLUSIONS: The rs4845384 polymorphism was associated with HBsAg seroclearance both spontaneously (P = 0.028, OR = 1.36, 95% CI = 1.03-1.78) and interferon induced (P = 0.013, OR = 1.83, 95% CI = 1.13-2.96), in a total of 725 subjects. Luciferase assays showed that pGL3-rs4845384G constructs had higher expression level than pGL3-rs4845384A constructs, especially in HepG2. 2.15 cell line. Quantitative real-time RT-PCR showed that chronic hepatitis B (CHB) patients had lower ADAR1 mRNA level than healthy individuals. The AA carriers of rs4845384 had lower ADAR1 mRNA expression than non-AA carriers. The non-response susceptible allele rs4845384A was functional for regulation of ADAR1 expression, so as to influence HBsAg seroclearance of CHB patients.

A missense polymorphism in ATF6 gene is associated with susceptibility to hepatocellular carcinoma probably by altering ATF6 level.

Accumulated evidences indicate that single nucleotide polymorphisms (SNP) are associated with risk of hepatocellular carcinoma (HCC). Activating transcription factor 6 (ATF6) is an important modulator of the unfolded protein response (UPR), which is regarded to be involved in carcinogenesis. So we speculate that SNPs in ATF6 may be associated with susceptibility to HCC. We carried out a two-stage association study in three independent case-control groups in a total of 1,082 chronic hepatitis B (CHB) patients and 816 hepatitis B virus (HBV) related HCC patients in Han Chinese. Four SNPs which can represent all potential functional SNPs with MAF > 0.1 recorded in HapMap database in ATF6 gene were genotyped using TaqMan methods. Functional analyses were conducted to verify the biological significances of the associated SNP. We identified a missense SNP (rs2070150) was significantly associated with susceptibility to HCC (p = 0.008, 0.001 and 0.007 in Beijing_302, Beijing_You'an and Guangxi samples, respectively). This SNP was further validated in four independent groups of major HBV outcomes, indicating it may associate exclusively to HCC. ATF6 mRNA expression was significantly decreased as the disease progressed (p <0.001). Functional analyses show that the protective allele of rs2070150 could significantly increase the expression levels of ATF6 mRNA, as well as ATF6 regulated genes such as GRP78, XBP1 and CHOP. These findings indicate that a common missense SNP in ATF6 may contribute to susceptibility of HCC functionally.

Replication of genome wide association studies on hepatocellular carcinoma susceptibility loci in a Chinese population.

BACKGROUND: Genome-wide association studies (GWAS) have identified three loci (rs17401966 in KIF1B, rs7574865 in STAT4, rs9275319 in HLA-DQ) as being associated with hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC) in a Chinese population, two loci (rs2596542 in MICA, rs9275572 located between HLA-DQA and HLA-DQB) with hepatitis C virus-related HCC (HCV-related HCC) in a Japanese population. In the present study, we sought to determine whether these SNPs are predictive for HBV-related HCC development in other Chinese population as well. METHOD AND FINDINGS: We genotyped 4 SNPs, rs2596542, rs9275572, rs17401966, rs7574865, in 506 HBV-related HCC patients and 772 chronic hepatitis B (CHB) patients in Han Chinese by TaqMan methods. Odds ratio(OR)and 95% confidence interval (CI) were calculated by logistic regression. In our case-control study, significant association between rs9275572 and HCC were observed (P = 0.02, OR = 0.73, 95% CI = 0.56-0.95). In the further haplotype analysis between rs2596542 at 6p21.33 and rs9275572 at 6p21.3, G-A showed a protective effect on HBV-related HCC occurrence (P<0.001, OR = 0.66, 95% CI = 0.52-0.84). CONCLUSION: These findings provided convincing evidence that rs9275572 significantly associated with HBV-related HCC.

Association of epidermal growth factor and epidermal growth factor receptor polymorphisms with the risk of hepatitis B virus-related hepatocellular carcinoma in the population of North China.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common solid malignant tumor occurring worldwide that leads to the third largest cause of death compared to other cancers. Genetic and environmental factors are involved in the pathogenesis of HCC. Epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) can stimulate the proliferation of epidermal and epithelial cells. The EGF signal pathway has a relationship with the growth of the embryo, tissue repairing, and tumorigenesis. METHODS: In this study, 416 patients with hepatitis B virus infection (HBV)-related HCC and 645 individuals who had never been infected with HBV of the Chinese Han population were enrolled. Eight single-nucleotide polymorphisms (SNPs), whose minor allele frequency >20% in the EGF and EGFR genes, were genotyped to examine their associations with hepatocarcinogenesis. Genotyping experiments were carried out using TaqMan. RESULTS: There were significant differences in genotype distributions (p=0.005) and allele frequencies (p=0.001, odds ratio [OR]=1.43, 95% confidence interval [CI]=1.15-1.79) of rs11569017 in the EGF gene between the HCC and control groups. After binary logistic regression to determine independent factors for susceptibility to HCC under an additive model, rs11569017 was still independently associated with the susceptibility to HCC (p=0.021, OR=1.48, 95% CI=1.06-2.07), but no significant differences in other SNPs were found. Additionally, the haplotype T-G constructed by rs11569017 and rs4444903 of the EGF gene might increase the risk of HBV-related HCC (p=0.002, OR=1.44, 95% CI=1.15-1.82). CONCLUSION: The rs11569017 T allele was associated with susceptibility to HBV-related HCC.

Polymorphisms in the VEGFA promoter are associated with susceptibility to hepatocellular carcinoma by altering promoter activity.

Accumulated evidences indicate that single nucleotide polymorphisms (SNP) in angiogenesis and tumorigenesis related genes are associated with risk of hepatocellular carcinoma (HCC). Vascular endothelial growth factor A (VEGFA), one of the most significant mediators of angiogenesis, plays an important role in carcinogenesis and development via promoting tumor growth. We carried out a two-stage association study in 1,838 chronic hepatitis B (CHB) patients and 1,207 hepatitis B virus (HBV) related HCC patients in Han Chinese populations from Beijing, Guangxi and Jiangsu. We systematically screened polymorphisms in the VEGFA gene and examined the association between the SNPs and susceptibility to HCC. Functional analyses were conducted to verify biological significances of associated SNPs. We identified two promoter SNPs (rs833061 and rs1570360) were associated with susceptibility to HCC (rs833061: ptrend = 0.008 in Youan_Beijing samples, ptrend = 0.01 in Guangxi samples, ptrend = 0.01 in Jiangsu samples. rs1570360: ptrend = 0.00003 in Youan_Beijing samples, ptrend = 0.006 in Guangxi samples, ptrend = 0.02 in Jiangsu samples). These two SNPs were further validated in four independent groups of major HBV outcomes, indicating rs833061 and rs1570360 may associate exclusively to HCC. Functional analyses show that CA haplotype constructed by rs833061 and rs1570360 had higher luciferase activity compared with TG haplotype (p < 0.05). A 18 bp insert/del polymorphism was in absolute linkage disequilibrium (LD) with rs833061. The 18 bp insert allele created a Sp1 binding site. We observed higher VEGFA transcription in peripheral blood of HCC patients compared with CHB patients and healthy individuals (p < 0.05). These findings indicate that VEGFA promoter SNPs may contribute to susceptibility of HCC by altering promoter activity.

Association of polymorphisms in mitofusin-2 gene with type 2 diabetes in Han Chinese.

MFN2 and ESRRA are candidate genes involved in the pathogenesis of T2D. Five tag-SNPs in MFN2 gene and three in ESRRA gene were selected and genotyped with TaqMan or PCR-RFLP method in stage 1 populations (555 patients with T2D and 649 control subjects) and stage 2 populations (546 patients with T2D versus 419 control subjects) in Han Chinese. And combining our published data, we estimated the interactions between genetic variants in the MFN2, ESRRA, and PGC-1α genes on the T2D risk using MDR. rs873458 (G > A) and rs2878677 (C > T) in MFN2 gene were significantly associated with T2D (P = 0.005 and 0.01) in stage 1 populations, and the association of other SNPs with T2D was not found. In stage 2 populations, we further confirmed the association between rs2878677 and T2D (P = 0.01). Combining the two stage populations, the data supported more significant effect of rs873458 and rs2878677 on T2D risk (P = 0.003 and 0.0001). A-C-G-T-C and G-T-C-T-C in MFN2 had significant association with T2D (P = 0.007 and 0.009). The present study also provided the evidence that MFN2 had interactions with PGC-1α (P < 0.0001) or ESRRA (P < 0.0001). This study suggested a role of MFN2 polymorphism in the risk of T2D; however, further studies are needed.

A 3' UTR SNP in COL18A1 is associated with susceptibility to HBV related hepatocellular carcinoma in Chinese: three independent case-control studies.

BACKGROUND: Accumulated evidences indicate that single nucleotide polymorphisms (SNP) in angiogenesis and tumorigenesis related genes are associated with risk of Hepatocellular carcinoma (HCC). COL18A1 encodes the precursor of endostatin, which is a broad-spectrum angiogenesis inhibitor, and we speculate that SNPs in COL18A1 may be associated with susceptibility to HCC. METHODS AND FINDINGS: We carried out a 2-stage association study in 3 independent case-control groups in a total of 1067 chronic hepatitis B (CHB) patients and 808 hepatitis B virus (HBV) related HCC patients in Han Chinese. Four SNPs which can represent all potential functional SNPs with MAF>0.1 recorded in HapMap database were genotyped using TaqMan methods. Levels of total COL18A1 mRNA were also examined using quantitative real-time RT-PCR. We found that rs7499 located in 3'-UTR to be strongly associated with HBV related HCC (P(combined) = 0.0000005, OR = 0.72, 95%CI = 0.63-0.82). COL18A1 mRNA expression was significantly decreased as the disease progressed (P = 0.000026). CONCLUSION: These findings indicate that COL18A1 rs7499 may contribute to the risk of HCC in Han Chinese.

Polymorphisms in ADAR1 gene affect response to interferon alpha based therapy for chronic hepatitis B in Han Chinese.

Host genetic polymorphisms in interferon pathway genes are reported to be associated with response to interferon therapy. Five hundred and forty-eight α interferon treatment-naïve chronic hepatitis B patients were enrolled in the retrospective nested case-control study. All patients received α interferon based treatment and were examined for therapy efficacy. We genotyped 115 polymorphisms from 16 interferon pathway genes using the MassArray system. We identified rs4845384 in ADAR1 gene is strongly associated with the outcome of interferon therapy allele dose-depended (P=0.0005), with decreased odds ratios of 0.69 and 0.27 for GA and AA genotypes, respectively (95% confidence interval, 0.47-0.99 for GA; 0.11-0.64 for AA). Our study suggested that rs4845384 in ADAR1 associates with treatment-induced clearance of chronic hepatitis B.

Polymorphisms in the potential functional regions of the TGF-ß 1 and TGF-ß receptor genes and disease susceptibility in HBV-related hepatocellular carcinoma patients.

Hepatocellular carcinoma (HCC) is a disease of multiple etiologies caused by the accumulation of genetic and epigenetic defects. Current evidence indicates that the transforming growth factor beta (TGF-ß) signaling pathway has a significant impact on different cellular process. Members of the TGF-ß superfamily (TGF-ß1, the type I TGF-ß receptor [TßRI], type II TGF-ß receptor [TßRII], and type III TGF-ß receptor]) play an important role in tumorigenesis. Numerous studies show that genetic polymorphisms in TGF-ß superfamily genes are associated with HCC in East Asian populations. We studied 16 single nucleotide polymorphisms (SNPs) in four genes (TGF-ß1, TßRI, TßRII, and TßRIII) to examine their associations with hepatocarcinogenesis. A total of 1228 Chinese Han participants were enrolled in the study (881 control participants who were negative for all hepatitis B virus [HBV] serum markers and 347 case participants with HBV-related HCC). Genotyping was conducted using the TaqMan method. The results showed that the frequency of the rs1805110 T allele was significantly higher in the case group than in the control group (P = 0.034). After stratification, the results for rs1805110 remained significant in male participants (P = 0.005), but there was no statistical difference in females. In males, the frequency of the C-C-G-C-A haplotype resulting from SNPs rs1805110, rs2810904, rs1805112, rs284878, and rs1804506 in TßRIII was significantly lower in the case group than in the control group (P = 0.001), whereas the reverse was true for the T-C-G-C-A haplotype (P = 0.036). We conclude that the rs1805110T allele is associated with susceptibility to HBV-related HCC in males.