Possible Involvement of the NS3 Protein of Hepatitis C Virus in Hepatocarcinogenesis: Its Interaction with the p53 Tumor Suppressor

Hepatitis C virus (HCV), a member of the Flaviviridae family, is an enveloped virus, whose genome is single-stranded, positive-sense RNA of approximately 9.5 kb. The viral genome exhibits a considerable degree of sequence variation, based on which HCV is currently classified into at least 6 clades (previously called genotypes) and more than 60 subtypes (1,2). The HCV genome encodes a polyprotein consisting of about 3010-3033 amino acid residues. A number of studies have shown that this polyprotein is cleaved cotranslationally and posttranslationally into mature viral proteins, which are arranged in the order NH(2)-C-E1-E2-p7-NS2-NS3-NS4A-NS4B-NS5A-NS5B-COOH (3,4).