Analysis of p53 and ras gene mutations in hepatocellular carcinoma from a Western country

Objective: To evaluate the frequency of p53 tumour suppressor gene and H- and K-ras oncogene mutations in both neoplastic and distant cirrhotic non-neoplastic tissue in Italian patients with hepatocellular carcinoma (HCC). Patients: Ten men and four women (mean age 62 +/-7 years) with HCC associated with cirrhosis, who underwent resection. More than half the patients had a lesion over 3 cm in diameter and in 12 cases carcinoma was well differentiated. Methods: Exons 4 to 9 of p53 and codons 12, 13 and 61 of the H- and K-ras genes were analyzed by the polymerase chain reaction-single strand conformation polymorphism method in both neoplastic and non-adjacent cirrhotic tissue and in cell lines harbouring known mutations as positive controls. Results: No aberrant migrating fragments were observed in tumoral and cirrhotic non-neoplastic tissue. Conclusion: Our findings suggest that p53 mutation is a rare occurrence in HCC, at least in countries with a low incidence of this cancer. They also confirm that H- and K-ras mutations are infrequent in HCC and play a minimal role in hepatocarcinogenesis.