We investigated 22 HCCs and, as controls, their corresponding tumour-free liver tissues, seven livers with primary biliary cirrhosis and four morphologically normal livers. p53 overexpression, which is usually associated with point mutations of the p53 gene, was detected in 10 of the 22 HCCs by immunoblotting and immunohistochemistry. p53 expression was restricted to the nucleus in the positive cells, while all cells in the control tissues were negative.