Objective: To study the expression of P21 and P15 proteins in liver tissue of chronic viral hepatitis (CH) and hepatocellular carcinoma (HCC) and their relation to cell apoptosis.
Methods: The expression of P21 and P15 proteins in 36 CH patients liver tissues were detected by immunohistochemistry and the DNA damage of the hepatocytes were detected by TDT mediated dUDT nick and labeling (TUNEL). 10 cases of HCC were also studied.
Results: P21 and P15 proteins mainly distributed in the interstitium of portal areas, the piece meal necrotic sites and the nuclei and cytoplasm of the hepatocytes. The higher expression of P21 and P15 proteins in the interstitium and nuclei of the hepatocytes was seen in CH as compared with that in HCC. The levels of expression of P21 and P15 in moderate and severe type CH were higher with that of the mild type CH (P <0.05). The correlative coefficient of expression of P21 and P15 with the DNA damage of hepatocytes were 0.56, 0.51 respectively (P <0.01).
Conclusions: The enhanced expression of P21 and P15 proteins in CH correlated with the injury of liver tissues and apoptosis of hepatocytes.