Altered expression of cell cycle and apoptotic proteins in human liver pathologies.

Τhe expression of cell cycle (P53, Ki-67, P21, and P27) and apoptotic proteins (BCL-2 and BAX) was investigated by immunohistochemistry in paraffin-embedded formalin-fixed tissues of normal and pathologic liver. An increased frequency of expression of P21 in cirrhosis and hepatocellular carcinoma (HCC) (p=0.003 and p=0.001 respectively) was found; P27 protein expression was more frequent in hepatitis (p=0.001) and HCC (p=0.003) when compared with normal tissue. BCL-2 protein was markedly more frequent in steatohepatitis (p<0.05) as compared to normal liver, in hepatitis cases (p=0.002) and in metastases (p<0.033). The expression of BAX was more frequent in hepatitis (p=0.001) and cirrhosis (p<0.001). We demonstrated in our study the expression of these proteins at different levels in liver pathologies. These findings have implications for understanding the evolution from liver inflammation to cirrhosis and associated carcinogenesis.