Hepatitis B virus integration, fragile sites, and hepatocarcinogenesis

MA Feitelson, J Lee - Cancer letters, 2007 - Elsevier
Cancer letters, 2007Elsevier
Chronic liver disease associated with long term hepatitis B virus (HBV) infection contributes
importantly to the development of hepatocellular carcinoma (HCC). A salient feature of these
chronic infections is the integration of subgenomic HBV DNA fragments into many different
locations within the host DNA, suggesting that integration is random. Although this may
promote genetic instability during liver regeneration which accompanies a bout of chronic
liver disease, the actual role of integrated HBV DNA in hepatocarcinogenesis is uncertain …
Chronic liver disease associated with long term hepatitis B virus (HBV) infection contributes importantly to the development of hepatocellular carcinoma (HCC). A salient feature of these chronic infections is the integration of subgenomic HBV DNA fragments into many different locations within the host DNA, suggesting that integration is random. Although this may promote genetic instability during liver regeneration which accompanies a bout of chronic liver disease, the actual role of integrated HBV DNA in hepatocarcinogenesis is uncertain. Importantly, most integration events retain the HBV open reading frame encoding the HBx antigen (HBxAg), which is the virus contribution to HCC. In addition, many integration events reported in the literature occur near or within fragile sites or other cancer associated regions of the human genome that are prone to instability in tumor development and progression. Genetic instability associated with integration potentially alters the expression of oncogenes, tumor suppressor genes, and microRNAs (miRNAs) that may contribute importantly to tumorigenesis. If so, then selected integration events may alter pathways that are rate limiting in hepatocarcinogenesis, thereby providing targets with diagnostic/prognostic potential and for therapeutic intervention.
Elsevier