H epatitis B, caused by hepatitis B virus (HBV) infection, is very common in Asia, Africa, and the Middle East. It is estimated that there are 280 million carriers worldwide, representing more than 5% of the global population. Chronic infection with HBV is a major risk factor for the development of hepatocellular carcinoma (HCC); however, the mechanism by which HBV induces events leading to HCC has not been clearly elucidated. The HBV genome consists of four overlapping open reading frames encoding DNA polymerase, surface antigen, core protein, and a regulatory X protein [hepatitis B virus X protein (HBx)].