Wenting Tan

Regulatory polymorphisms in the IL-10 gene promoter and HBV-related acute liver failure in the Chinese population

Summary.  Recent reports indicated that high levels of interleukin 10 (IL‐10) contribute to the monocytes paralysis and poor clinical outcome in acute liver failure (ALF). Polymorphisms in the promoter region of IL‐10 affect IL‐10 production and confer susceptibility to inflammatory diseases. The aim of this study was to determine the possible association of the three polymorphisms (A‐1082G, T‐819C, A‐592C) in the IL‐10 gene promoter with the susceptibility to hepatitis B virus (HBV)‐related ALF in a Chinese population. The IL‐10 gene promoter polymorphisms were genotyped in 414 unrelated healthy blood donors, 367 asymptomatic HBV carriers and 345 HBV‐related ALF patients. Functional analyses were conducted to verify the biological significances of the associated genetic variations. The allele frequencies of IL‐10−592C and −819C were significantly higher in HBV‐related ALF patients than in blood donors and asymptomatic HBV carriers. Logistic regression analysis and stratification analysis with adjustment for age and sex indicated that the polymorphisms of A‐592C and T‐819C were associated with susceptibility to HBV‐related ALF (P = 6.9 × 10−7), and the ‐1082A‐819C‐592C haplotype in the IL‐10 gene promoter were associated with an increased susceptibility to ALF in HBV carriers (dominant model, P = 0.0002, odds ratio = 1.60, 95% CI 1.25–2.07). Functional analyses showed that the A‐592C polymorphism is a nuclear proteins binding site, and the disease susceptible −592C allele had a higher transcription activity compared with −592A allele. This study emphasizes the importance of IL‐10 in the pathophysiology of HBV‐related ALF on the population level.

Association of TBX21 gene haplotypes in a Chinese population with systemic lupus erythematosus

Objective: T-cell-specific T-box transcription factor (T-bet) is a member of the T-box family of transcription factors regulating type 1 T-helper (Th1) cell development and is thought to be linked with several autoimmune diseases including systemic lupus erythematosus (SLE). The aim of this study was to evaluate whether T-bet gene (TBX21) polymorphisms or its haplotypes are associated with SLE in a Chinese population. Methods: The study included 248 cases with SLE and 261 gender- and age-matched healthy controls. The polymorphisms T-1993C (rs4794067) and T-1514C (rs17250932) in the TBX21 promoter were identified by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Results: The frequency of both the -1993T and the -1514T allele were significantly higher in SLE patients than in controls. By haplotype analysis, there was significantly decreased frequency of the haplotype at positions -1993C/-1514C in the case group compared with the control group (p = 0.0002). Multifactorial logistic regression analysis showed that individuals with CC/CC haplotype homozygotes had a decreased susceptibility to SLE [p = 0.0004, odds ratio (OR) 0.316, 95% confidence interval (CI) 0.167–0.599]. Conclusion: Our results suggest that the -1993C/-1514C haplotype may be a protective factor for genetic susceptibility to SLE in the Chinese population.

SLCO1B1 *15 haplotype is associated with rifampin-induced liver injury

The organic anion transporting polypeptide 1B1 (OATP1B1, encoded by SLCO1B1) plays an important role in the transport of endogenous and xenobiotic compounds, such as bile acids and rifampin. In this study, the association between OATP1B1 polymorphisms and rifampin hepatotoxicity was investigated using integrated population genetic analysis and functional studies. A total of 273 unrelated patients treated with rifampin were recruited. The allele frequencies were examined in patients with drug (rifampin)-induced liver injury (DILI) (n = 118) and without (non-DILI) (n = 155). Functional analyses were conducted to determine whether the inhibition of bile acids by rifampin was associated with OATP1B1 variants. In the present study, 24 single nucleotide polymorphisms (SNPs) in OATP1B1 were detected in a Chinese population, with two of them causing an amino acid change (rs2306283 and rs4149056). The haplotypes constructed by these two SNPs were OATP1B1 *1a, *1b, *5 and *15, with their respective frequencies being 23.44, 66.30, 0.73 and 9.52% in a total of 273 individuals. The logistic regression analysis indicated that the *15 haplotype was associated with susceptibility to DILI (p = 0.03, OR = 2.04, 95% CI 1.05-3.96). The frequency of the *15 haplotype in DILI patients was significantly higher than that in non-DILI patients (p = 0.03). In the subgroup analysis, the *15 haplotype was associated with susceptibility to cholestatic/mixed injury (p = 0.03, OR = 2.31, 95% CI 1.06-5.02). Functional assessment of the OATP1B1 *15 haplotype revealed that the activity of bile acid uptake was markedly reduced compared to the three other haplotypes. In the inhibition study, the inhibition by rifampin in the *15 haplotype was greater compared to that in the other haplotypes. These results suggest that the OATP1B1 *15 haplotype is an important predisposing factor for rifampin-induced liver injury.

A cis-acting regulatory variation of the estrogen receptor α (ESR1) gene is associated with hepatitis B virus-related liver cirrhosis.

The hepatic fibrogenesis and sexual dimorphism of hepatitis B virus‐related liver cirrhosis (HBV‐LC) are related to estrogen and its receptors. Abnormal expression of estrogen receptor α (ESR1) is implicated in the development of cirrhosis in both animal models and humans. Here, we examine whether the ESR1 polymorphisms are related to HBV‐LC risk among chronic HBV carriers, and we investigate the functional significance of positively associated polymorphisms. A total of 2,404 unrelated Chinese HBV carriers were recruited to conduct the two‐stage designed case–control study. Two ESR1 haplotype tagging polymorphisms, c.30T>C (rs2077647) and c.453‐397T>C (rs2234693), were genotyped in 1,285 patients with HBV‐LC and in 1,119 asymptomatic HBV carriers. We observed a significantly increased susceptibility to HBV‐LC associated with the c.30C allele (P = 4.2×10−8), c.453‐397C allele (P = 2.0×10−8), and [c.30C; c.453‐397C] haplotype (Dominant model, P = 8.85×10−10, odds ratio = 1.50, 95% CI 1.32∼1.71) compared with the T alleles and (c.30T; c.453‐397T) haplotype of c.30T>C and c.453‐397T>C polymorphisms, respectively. Functional analyses were conducted to verify the biological functions of the associated genetic variations and showed that the c.453‐397T>C polymorphism is a novel c.453‐397C allele‐specific and c‐myb‐dependent enhancer‐like cis‐acting regulatory variation and could be part of the genetic variations underlying the susceptibility of individuals to HBV‐LC. Hum Mutat 32:1128–1136, 2011. ©2011 Wiley‐Liss, Inc.

Effect of HLA-DP and IL28B gene polymorphisms on response to interferon treatment in hepatitis B e-antigen seropositive chronic hepatitis B patients

The reason why the majority of chronic hepatitis B (CHB) patients do not respond to conventional interferon (IFN)‐α or pegylated interferon (PEG IFN) treatment has not been formally demonstrated. The aim of this study was to investigate the association between single nucleotide polymorphisms (SNPs) and response to IFN‐α or PEG IFN therapy in Chinese patients with CHB.

Estrogen receptor alpha gene polymorphisms and risk of HBV-related acute liver failure in the Chinese population

BackgroundThe sexual dimorphism of hepatitis B virus (HBV) -related liver diseases is related with estrogen and its receptors. Recent reports indicate that abnormal expression of estrogen receptor alpha (ESR1) may be a hallmark for the progression of liver disease and HBV carriers presenting variant ESR1 have an extremely aggressive clinical course. Here we examine whether the ESR1 polymorphisms or its haplotypes are related to HBV-related acute liver failure (ALF) risk among chronic HBV carriers in a Chinese population.MethodsA total of 1216 unrelated Han Chinese HBV carriers were recruited in this hospital-based case–control study, including 359 HBV surface antigen (HBsAg) carriers affected with ALF and 857 asymptomatic HBsAg carriers. Two ESR1 haplotype tagging polymorphisms, c.30 T > C (rs2077647) and c.453-397 T > C (rs2234693), were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.ResultsWe observed a significantly increased susceptibility to HBV-ALF associated with the c.30 C allele (P = 8.65 × 10-4), c.453-397 C allele (5.37 × 10-4) and [c.30 C; c.453-397 C] haplotype (Dominant model, P =0.0004, odds ratio = 1.53, 95% CI 1.23 ~ 1.96) compared with the T alleles and [c.30 T; c.453-397 T] haplotype of c.30 T > C and c.453-397 T > C polymorphisms, respectively.ConclusionsOur study suggests that [c.30 C; c.453-397 C] hapotype may be a risk factor for genetic susceptibility to HBV-related ALF in the Chinese population. It also emphasizes the importance of ESR1 in the pathophysiology of HBV-related ALF on the population level.

Association of TBX21 promoter polymorphisms with type 1 autoimmune hepatitis in a Chinese population

The T-box transcription factor T-bet is a key regulator for the lineage commitment in CD4 Th1 cells and CD8 T cells by activating the hallmark production of interferon-γ, and its expression level is linked to autoimmune diseases. T-1993C and T-1514C polymorphisms in the TBX21 gene (encoding T-bet) promoter can affect transcription activity. We investigated the distributions of these functional polymorphisms in 84 adult patients with type 1 autoimmune hepatitis (AIH-1) and 318 healthy controls. Intracellular T-bet staining of polarized CD4 Th1 cells from healthy controls corresponding to T-1993C genotypes were analyzed by flow cytometry. The -1993C allele frequency was 3.0% in AIH-1 and 11.8% in controls (p = 0.000 25). Individuals carrying the -1993C allele had a decreased risk to AIH-1 compared with those without the -1993C allele (p = 0.0016, odds ratio [OR] = 0.22, 95% confidence interval = 0.09-0.56). No association was found between the T-1514C polymorphism and AIH-1. The onset age of AIH-1 was also accelerated among -1993TT homozygotic individuals (p = 0.013). The fractions of T-bet positive Th1 cells in the -1993TT homozygotes were 2.2-fold higher than those in -1993CC homozygotes (p = 0.002). Our results suggest that the T-1993C polymorphism in the TBX21 promoter influences susceptibility to AIH-1 in a Chinese population.

Association of TBX21 T-1993C polymorphism with viral persistence but not disease progression in hepatitis B virus carriers

Aim:  Transcription factor T‐bet is responsible for the differentiation of naive T lymphocytes, and its expression level is linked with different responses to some viral infections, including hepatitis B virus (HBV) infection. In this report we examine whether promoter polymorphisms of the TBX21 gene (encoding T‐bet) are associated with susceptibility to HBV persistence or disease progression in chronic HBV carriers.

PERFORMANCE OF PROTEIN INDUCED BY VITAMIN K ABSENCE OR ANTAGONIST-II (PIVKA-II) FOR HEPATOCELLULAR CARCINOMA SCREENING IN CHINESE POPULATION

Background: Alpha-fetoprotein (AFP) has long been used as an effective biomarker for hepatocellular carcinoma (HCC) screening; however, not all HCC patients can be detected with an elevated AFP level, especially in early HCC patients. Protein Induced by vitamin K absence or antagonist-II (PIVKA-II) is another serum biomarker linked to HCC; however, sensitivity and specificity remain controversial and data in Chinese groups is even rarer. Objectives: To evaluate the performance of PIVKA-II alone and combined with AFP in HCC screening in Chinese population. Patients and Methods: This retrospective study enrolled 150 HCC patients in Southwest Hospital, of which 16 patients were excluded due to lack of basic information. A total of 347 patients with hepatitis B, 105 with non-HCC cancers and 53 healthy people were enrolled as controls. Levels of AFP and PIVKA-II were measured by chemiluminescence enzyme immunoassay (CLEIA) and chemiluminescent microparticle Immunoassay (CMIA), respectively. Results: The sensitivity and specificity of PIVKA-II were 74.6% and 67.8% at a cutoff of 40 mAU/mL and 64.2% and 89.7% at a cutoff of 200 mAU/mL. The sensitivity and specificity of AFP were 76.7% and 65.0% at a cutoff of 20 ng/mL and 60.4% and 88.9% at a cutoff of 195.23 ng/mL. The combination of two markers had a sensitivity and specificity of 91.1% and 41.0%, respectively. The area under the receiving operating curve (AUROC) for PIVKA-II (0.756, 95% confidence interval, CI: 0.695 - 0.816) was less than the AUROC for AFP (0.823, 95% CI: 0.780 - 0.865), and in combination, the AUROC increased to 0.843 (95% CI: 0.801 - 0.885). Conclusions: PIVKA-II was as efficient as AFP when used as a single marker for HCC screening and the combination of two biomarkers gave a better performance.

Genome-wide association study identifies HLA-DR variants conferring risk of HBV-related acute-on-chronic liver failure

Objective Acute-on-chronic liver failure (ACLF) is an extreme condition after severe acute exacerbation of chronic hepatitis B; however, the underlying genetic factors involved in its onset and progression are currently unclear. Design We carried out a genome-wide association study among 399 HBV-related ACLFs (cases) and 401 asymptomatic HBV carriers (AsCs, as controls) without antiviral treatment. The initial findings were replicated in four independent case–control sets (a total of 901 ACLFs and 1686 AsCs). The roles of risk variants on clinical traits of ACLF were also analysed. Results Among 1300 ACLFs and 2087 AsCs, we identified rs3129859 at human leucocyte antigen (HLA) class II region (chromosome 6p21.32) associated with HBV-related ACLF (combined Pdominant=2.64×10−20, OR=1.83). Analysis identified HLA-DRB1*12:02 as the top susceptible HLA allele associated with ACLF (p=3.94×10−6, OR=2.05). The association of rs3129859 was robust in ACLF subgroups (ACLFs with liver cirrhosis, p=1.36×10−16; ACLFs without liver cirrhosis, p=1.52×10−7), and patients at low-replicative phase (p=6.36×10−11, OR=2.29) or HBV e antigen-negative chronic hepatitis B phase (p=1.51×10−14, OR=1.86). Clinical traits analysis in patients with ACLF showed that the risky rs3129859*C allele was also associated with prolonged prothrombin time, faster progression to ascites development and higher 28-day mortality. Conclusions Our genome-wide association study identified HLA-DR as the major locus for susceptibility to HBV-related ACLF. Our findings highlight the importance of HLA class II restricted CD4+ T-cell pathway on the immunopathogenesis of HBV-related ACLF.