Hepatitis C virus core protein promotes cell proliferation through the upregulation of cyclin E expression levels

Aims/Background: The hepatitis C virus (HCV) core protein is known to play an important role in hepatocarcinogenesis. Recent studies have suggested that the increased proliferation rate of hepatocytes is a major risk factor for the development of hepatocellular carcinoma. In this study, we investigated whether the HCV core protein promotes the cell growth rate through the modulation of cyclin E expression levels. Methods/Results: HCV core stable transfectant Rat-1 cell lines showed a markedly increased proliferation rate compared to mock cells. Cyclin E expression and its associated kinase activities were remarkably increased in HCV core stable transfectants. Cyclin E mRNA levels were also upregulated in these cell lines. Conclusions: Our data suggest that the HCV core protein promotes cell proliferation through upregulation of the cyclin E expression levels, implying this property of HCV core protein plays an important role in hepatocarcinogenesis.