[Hepatocellular carcinoma: molecular biology aspects].

Chronic liver diseases, in particular chronic HBV and HCV infections, frequently progress to liver cirrhosis and HCC. The molecular events underlying hepatocarcinogenesis are not yet well defined. It appears likely, however, that HCCs result from a stepwise carcinogenesis: due to chronic liver disease there is liver cell necrosis, inflammation and regeneration with a high mitotic rate of liver cells. In this setting, chromosomal DNA rearrangements occur which may result in the activation of cellular oncogenes or inactivation of tumor suppressor genes. Viral genes or gene products as well as cofactors, such as alcohol or aflatoxins, may make a specific contribution to these molecular events. Apart from the molecular aspects of hepatocarcinogenesis, for clinical practice the implementation of measures to prevent or treat chronic liver diseases should reduce the incidence of HCCs, one the most frequent malignancies in some areas of the world.