Hepatitis B virus-induced hepatocellular carcinoma: the role of the virus x protein.

Hepatocellular carcinoma (HCC) is one of the most common malignant diseases and has the fourth highest mortality rate worldwide. Chronic hepatitis B virus (HBV) infection has been identified as a major risk factor in HCC. Currently available evidence support a critical role of hepatitis B virus x (HBx) gene and protein in the pathogenesis of HBV-induced HCC. HBx protein is a multifunctional regulator that modulates cellular signal transduction pathways, transcriptional regulations, cell cycle progress, DNA repair, apoptosis, and genetic stability by interacting with different host factors. This review describes the current state of knowledge about the biological roles of this protein in the development of HCC.