[p16 and cyclinD1 protein expression and p16 gene mutation in primary human hepatocellular carcinoma].
OBJECTIVE: To elucidate the relationship between expression of p16 and cyclinD1 proteins and evaluate the role of p16 gene exon 2 mutation in hepatocellular carcinogenesis. METHODS: Streptavidin-peroxidase conjugated method(SP) was used to detect expressions of p16 and cyclinD1 proteins in 44 cases of hepatocellular carcinoma(HCC), and polymerase chain reaction single-strand conformation polymorphism analysis(PCR-SSCP) to detect p16 gene mutation in exon 2 in 12 cases of HCC and liver tissues adjacent to HCC. RESULTS: Expression rate and positive signal intensity of p16 protein in HCC were significantly lower(P < 0.01) and those of cyclinD1 protein in HCC were significantly higher (P < 0.05) than those in pericarcinomatous tissues. Of 12 fresh HCC tissues, p16 gene mutation in exon 2 was found in 2 cases, whereas that was not found in pericarcinomatous tissues. CONCLUSIONS: 1. Inactivation or/ and deletion of p16 protein may be one of important reasons which result in proliferation unbalance of cells. 2. p16 gene mutation in exon 2 presents in HCC, but it does not frequently occur in Chinese hepatocarcinogenesis. 3. p16 gene abnormality and cyclinD1 over expression may coact in HCC.