Article

Mechanisms of HBV-related hepatocarcinogenesis.

Oncogenesis and Molecular Virology Unit, Institut Pasteur, Inserm U579, 28 rue du Dr Roux, Paris cedex 15, France.
Journal of Hepatology (Impact Factor: 9.86). 04/2010; 52(4):594-604. DOI: 10.1016/j.jhep.2009.10.033
Source: PubMed

ABSTRACT The hepatitis B virus (HBV) is a small enveloped DNA virus, which primarily infects hepatocytes and causes acute and persistent liver disease. Epidemiological studies have provided overwhelming evidence for a causal role of chronic HBV infection in the development of hepatocellular carcinoma, but the molecular mechanisms underlying virally-induced tumourigenesis remain largely debated. In the absence of a dominant oncogene encoded by the HBV genome, indirect roles have been proposed, including insertional activation of cellular cancer-related genes by HBV DNA integration, induction of genetic instability by viral integration or by the regulatory protein HBx, and long-term effects of viral proteins in enhancing immune-mediated liver disease. Recent genetic studies indicate that HBV-related tumours display a distinctive profile with a high rate of chromosomal alterations and low frequency of beta-catenin mutations. This review will discuss the evidence implicating chronic HBV infection as a causal risk factor of primary liver cancer. It will also discuss the molecular mechanisms that are critical for the tumourigenic process due to long lasting infection with HBV.

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  • 12/2014; 26(6):730-1.

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