HBV precore G1896A mutation promotes growth of hepatocellular carcinoma cells by activating ERK/MAPK pathway

Chronic hepatitis B virus(HBV)infection is one of the leading causes of hepatocellular carcinoma(HCC).The HBV genome is prone to mutate and several variants are closely related to the malignant transformation of liver disease.G1896A mutation(G to A mutation at nucleotide 1896)is one of the most frequently observed mutations in the precore region of HBV,which prevents HBeAg expression and is strongly associated with HCC.However,the mechanisms by which this mutation causes HCC are unclear.Here,we explored the function and molecular mechanisms of the G1896A mutation during HBV-associated HCC.G1896A mutation remarkably enhanced the HBV replication in vitro.Moreover,it increased tumor formation and inhibited apoptosis of hepatoma cells,and decreased the sensitivity of HCC to sorafenib.Mechanistically,the G1896A mutation could activate ERK/MAPK pathway to enhanced sorafenib resistance in HCC cells and augmented cell survival and growth.Collectively,our study demonstrates for the first time that the G1896A mutation has a dual regulatory role in exacerbating HCC severity and sheds some light on the treatment of G1896A mutation-associated HCC patients.

Association of miRNA-122-binding site polymorphism at the interleukin-1 a gene and its interaction with hepatitis B virus mutations with hepatocellular carcinoma risk

This study was designed to investigate the contribution of miRNA-122-binding site polymorphism at the IL-1A gene and its multiplicative interactions with hepatitis B virus （HBV） mutations in the risk of hepatocellular carcinoma （HCC）. A total of 1021 healthy controls, 302 HBV surface antigen （HBsAg） seroclearance subjects, and 2011 HBsAg-positive subjects （including 1021 HCC patients） were enrolled in this study. Quantitative PCR was used to genotype rs3783553. HBV mutations were determined by direct sequencing. Multivariate logistic regression analyses were performed to test the associations of rs3783553, mutations, and their interactions with the risk of HCC. No significant association was found between rs3783553 and the risk of HCC among healthy controls, HBsAg seroclearance subjects, HBsAg-positive subjects without HCC, and all controls. Additionally, rs3783553 was not significantly associated with chronic HBV infection, liver cirrhosis, HBV e antigen seroconversion, abnormal alanine aminotransferase, and high viral load （ 〉 10^4 copies/ml）. However, the TTCA insertion allele of rs3783553 was significantly associated with an increased frequency of HBV C7A mutation compared with homozygous TTCA deletion carriers [（del/ins ＋ ins/ins） vs. del/del, adjusted odds ratio （OR）= 1.48, 95% confidence interval （CI）= 1.09-2.02, P = 0.013]. Multiplicative interaction of rs3783553 with HBV preS deletion significantly reduced the risk of HCC in males, with an adjusted OR of 0.64 （95% CI = 0.42-0.98; P = 0.041） after age and HBV genotype were adjusted. Although rs3783553 did not significantly affect genetic susceptibility to HBV-related HCC, its variant allele may predispose the host to selecting HBV C7A mutation during evolution and significantly reduce the risk of HCC caused by HBV preS deletion. This study provides an insight into the complex host-virus interaction in HBV-induced hepatocarcinogenesis and is helpful in determining HBsAg-positive subjects who are likely to develop HCC.

Association of human leukocyte antigen-DR-DQ-DP haplotypes with the risk of hepatitis B virus-related hepatocellular carcinoma

Aim:Genetic polymorphisms of human leukocyte antigen(HLA)class II molecules are associated with chronic hepatitis B virus(HBV)infection.We aimed to investigate the impacts of HLA-II haplotypes on viral evolution and the risks of HBV-caused liver diseases.Methods:HLA-DR-DQ-DP haplotypes were estimated in 1210 healthy controls,296 HBV clearance subjects,301 asymptomatic hepatitis B surface antigen carriers,770 chronic hepatitis B patients,443 HBV-related liver cirrhosis(LC)patients,and 1037 HBV-related hepatocellular carcinoma(HCC)patients.HBV mutations were determined by sequencing.The associations of HLA-DR-DQ-DP haplotypes with viral mutations and the risks of liver diseases were assessed by multivariate logistic regression.Results:Compared to HBV-free subjects,the haplotypes CCAACG,CCGACG,TCAATA,and TCGATA were associated with decreased HCC risk,with an odds ratio(OR)[95%confidence interval(CI)]of 0.62(0.40-0.95),0.60(0.39-0.92),0.73(0.54-0.98),and 0.58(0.42-0.78),respectively.CCAACG,CCGACG,and TCAATA were significantly associated with decreased frequencies of the HCC-risk HBV mutations:preS1 deletion,APOBECsignature HBV mutations in the core promoter and preS regions,A51C/T,G104C/T,and G146C/T.TCGATA and TTAACG were associated with increased LC risk,with an OR(95%CI)of 1.54(1.03-2.30)and 2.23(1.50-3.33),respectively.However,TCGATA and TTAACG were not consistently associated with the cirrhosis-risk HBV mutations.Conclusion:CCAACG,CCGACG,and TCAATA are inversely associated with HCC risk,possibly because they are involved in creating an immune microenvironment attenuating the generation of HCC-risk HBV mutations.TCGATA and TTAACG might predispose the polarity of immunity towards Th17 isotype related to LC.