The expression and correlation of p16,p21 gene in primary hepatocellular carcinoma

Background and purpose:P16 and P21 protein are suppressors that are mainly involved in modulating cell cycle and regulating cell proliferation. The deletion, inactivation of p16 and p21 genes may be related to multiple carcinogenesis and progression. This study was to investigate the P16, P21 protein expression, its deletion in hepatocellular carcinoma (HCC) and to evaluate the relationship between the p16, p21 gene and the hepatocarcinogenesis.. Methods:The expression of P16, P21 protein and the gene status in 42 cases of HCC and 36 cases of tumor-adjacent non-cancerous tissues were examined by Western Blotting and Reverse Transcription-Polymerase chain Reaction(RT-PCR). Results:The loss of p16 protein expression was observed in 24 cases of HCC (57.1%, 24/42) and in 5 cases of tumor-adjacent non-cancerous tissues (13.9%, 5/36), there were similar patterns for the loss of P21 protein expression, 45.2% (19/42) in HCC and 19.4% (7/36) in tumor-adjacent non-cancerous tissues, respectively (P0.05). 14 cases(38.9%,14/36) in HCCs only expressed the p16mRNA but did not express the protein. A lack of p16, p21 expression correlated with histological differentiation grade (P0.05) and the tumor size (P0.05), but not with the encapsulation and hepatocirrhosis. Conclusions:The p16 and p21 gene inactivation has a close relationship with hepatocarcinogenesis. P16 and P21 protein may have reference value to estimate the degree of differentiation and prognosis of primary hepatocellular carcinoma.