Project description:Hepatitis B virus (HBV) infection could cause hepatitis, liver cirrhosis and hepatocellular carcinoma. HBV-mediated pathogenesis is only partially understood, but X protein (HBx) reportedly possesses oncogenic potential. Exosomes are small membrane vesicles with diverse functions released by various cells including hepatocytes, and HBV harnesses cellular exosome biogenesis and export machineries for virion morphogenesis and secretion. Therefore, HBV infection might cause changes in exosome contents with functional implications for both virus and host. In this project, exosome protein content changes induced by HBV and HBx were quantitatively analyzed by SILAC/LC-MS/MS. Exosomes prepared from SILAC-labeled hepatoma cell line Huh-7 transfected with HBx, wildtype or HBx-null HBV replicon plasmids were analyzed by LC-MS/MS.
Project description:Chronic hepatitis B virus (HBV) infection is an incurable global health threat capable of causing liver disease and hepatocellular carcinoma. During the genesis of infection, HBV establishes an independent chromosome, cccDNA, consisting of the circular viral genome and host histones. The first viral protein expressed, HBx, induces degradation of a host silencing factor to facilitate infection. However, the relationship between cccDNA’s chromatin and early HBx transcription state remains poorly understood. Using reconstituted viral chromosomes, we found that nucleosomes in cccDNA drive HBx transcription. We corroborated these findings in cells and further showed that chromatin destabilizing drugs inhibit viral transcription and antigen expression in hepatocytes. Our results shed new light on a long-standing paradox and represent a novel therapeutic avenue for the treatment of chronic HBV.
Project description:Chronic hepatitis B virus (HBV) infection is an incurable global health threat capable of causing liver disease and hepatocellular carcinoma. During the genesis of infection, HBV establishes an independent chromosome, cccDNA, consisting of the circular viral genome and host histones. The first viral protein expressed, HBx, induces degradation of a host silencing factor to facilitate infection. However, the relationship between cccDNA’s chromatin and early HBx transcription state remains poorly understood. Using reconstituted viral chromosomes, we found that nucleosomes in cccDNA drive HBx transcription. We corroborated these findings in cells and further showed that chromatin destabilizing drugs inhibit viral transcription and antigen expression in hepatocytes. Our results shed new light on a long-standing paradox and represent a novel therapeutic avenue for the treatment of chronic HBV.
Project description:The hepatitis B virus X protein (HBx) has been implicated as an oncogene in both epigenetic modifications and genetic regulation during hepatocarcinogenesis, but the underlying mechanisms are not entirely clear. Long non-coding RNAs (lncRNAs), which regulate gene expression with little or no protein-coding capacity, are involved in diverse biological processes and in carcinogenesis. We asked whether HBx could promote hepatocellular carcinoma (HCC) by regulating the expression of lncRNAs.In this study, we investigated the alteration in expression of lncRNAs induced by HBx using microarrays, and our results indicate that HBx transgenic mice have a specific profile of liver lncRNAs compared with wild-type mice.
Project description:Chronic hepatitis B virus (HBV) remains to be the most common risk factor of hepatocellular carcinoma (HCC). While work has primarily focussed on understanding the direct and indirect mechanisms of Hepatitis B virus X protein (HBx) mediated hepatocarcinogenesis, from genetic and epigenetic perspectives, its influence on RNA modification mediated onset of liver malignancies is less well understood. This study explored the role of HBV-encoded HBx in altering the m6A methylome profile and its implications on the pathogenesis of HCC. We established HBx expressing stable HCC cell lines, Huh7-HBx and HepG2-HBx, and explored the transcriptomic and epitranscriptomic profiles by RNA-seq and MeRIP-seq, respectively. Preliminary results suggest that HBx promotes liver cell proliferation, migration, survival and overall m6A methylation in HCC cells and is involved in modulating the extracellular matrix. We show that HBx mediates liver cell transformation by upregulating KIAA1429 methyltransferase. HBx also drives the expression and hypermethylation of the extracellular matrix protein HSPG2/Perlecan and promotes tumourigenesis. Our findings indicate a potential interaction between KIAA1429 and HSPG2, thus could be novel targets in combating HBx-driven HCC and warrants further investigation.
Project description:Chronic hepatitis B virus (HBV) remains to be the most common risk factor of hepatocellular carcinoma (HCC). While work has primarily focussed on understanding the direct and indirect mechanisms of Hepatitis B virus X protein (HBx) mediated hepatocarcinogenesis, from genetic and epigenetic perspectives, its influence on RNA modification mediated onset of liver malignancies is less well understood. This study explored the role of HBV-encoded HBx in altering the m6A methylome profile and its implications on the pathogenesis of HCC. We established HBx expressing stable HCC cell lines, Huh7-HBx and HepG2-HBx, and explored the transcriptomic and epitranscriptomic profiles by RNA-seq and MeRIP-seq, respectively. Preliminary results suggest that HBx promotes liver cell proliferation, migration, survival and overall m6A methylation in HCC cells and is involved in modulating the extracellular matrix. We show that HBx mediates liver cell transformation by upregulating KIAA1429 methyltransferase. HBx also drives the expression and hypermethylation of the extracellular matrix protein HSPG2/Perlecan and promotes tumourigenesis. Our findings indicate a potential interaction between KIAA1429 and HSPG2, thus could be novel targets in combating HBx-driven HCC and warrants further investigation.
Project description:Hepatitis B virus (HBV) has been clearly recognized as an etiological factor for hepatocellular carcinoma (HCC). HBV encodes the potentially oncogenic HBx protein. We aimed to elucidate the molecular mechanism of HCC caused by HBx and to discover the biomarker related to HCC by HBx. Three experimental groups, 3, 9 and 13 month aged HBx Tg mice and age matched normal wild type B6 mouse which have same background of HBx Tg mice were used to find differentially expressed genes during HCC. Keywords: Genetic modification
Project description:Hepatitis B virus (HBV) has been clearly recognized as an etiological factor for hepatocellular carcinoma (HCC). HBV encodes the potentially oncogenic HBx protein. We aimed to elucidate the molecular mechanism of HCC caused by HBx and to discover the biomarker related to HCC by HBx. Three experimental groups, 3, 9 and 13 month aged HBx Tg mice and age matched normal wild type B6 mouse which have same background of HBx Tg mice were used to find differentially expressed genes during HCC. Keywords: Genetic modification 3-month-old, 9-month-old, 13-month-old wild type B6 mice vs 3-month-old, 9-month-old, 13-month-old HBx transfected mice; Biological replicates at each timepoint; 9 controls vs 9 HBx-mice