Relationship Between Hepatitis B Virus X Protein And Centromere Protein A

In previous studies, we observed HBx deleted mutant 30aa and 40aa in COOH terminal played a different role in proliferation and invasion of Huh7 cells. To investigate the molecular mechanism of the changed biologic features in hepatocellular carcinoma cells, we screened the differential expressed genes and proteins in two groups of Huh7 cells transfected with HBx (HBx3'-30/Huh7and HBx3'-40/Huh7) by gene chips and two dimensional electrophoresis. It was indicated that the expression of centromere protein A (CENP-A) was up-regulated in the process of transcription and protein translation. CENP-A expression was higher in tumor tissue than non-tumor tissue. The protein expression level of CENP-A was paralleled with the mRNA expression level. Over-expression of CENP-A can increase hepacellular carcinoma cells proliferation, while inhibition of CENP-A leads to apoptosis raise. These results showed that CENP-A over-expression was associated with HBx mutation. The mechanism of HBx mutation up-ragulated CENP-A was not disclosed yet. In this research we verified that CENP-A was highly expressed in hepatocelluar carcinoma(HCC) with HBx mutation compared with those without HBx mutation by means of western blot, immunohistochemical staining (IHC),PCR and sequence. Immunoprecipation result show there is no combination between HBx protein with CENP-A. This means we will put more effort on gene amplification and active transcription of CENP-A. The clarification of this mechanism would throw light on the hapatocarcinogenesis of HBV infection related HCC.