Study on p16 protein expression and p16 gene deletion in primary hepatocellular carcinoma

Objective: To study the p16 protein expression and p16 gene deletion in hepatocellular carcinoma (HCC), and to observe the relationship between p16 gene and HCC. Methods: Using immunohistochemistry and polymerase chain reaction (PCR), The expression of p16 protein and the deletion of p16 gene in 32 cases of HCC were examined. Results: The loss of p16 protein expression was observed in 20 cases of HCC (62.5%, 20/32) and in 1 case of tumor adjacent tissues (3.13%, 1/32), respectively (P0.01). The loss of p16 protein expression was closely correlated with poor histological differentiation of the tumor (P0.05), but not related to the size of the tumor and the serum AFP level (P0.05). The deletion rate of p16 gene in HCC (25%, 8/32) was significantly different from that in tumor adjacent hepatic tissues (3.13%, 1/32). The deletion rate of p16 gene was not correlated with the histological differentiation, the size of the tumor and the serum AFP level (P0.05). Conclusions: There is a close relationship between hepatocarcinogenesis and p16 gene inactivation. The expression of p16 protein may be an useful index to predict the prognosis.