[Expression of cellular oncogenes in human primary liver cell carcinoma]

With DNA-mRNA hybridization in situ technique, the expression of five oncogenes, c-N-ras, c-K-ras, c-H-ras, c-myc and c-fos, was observed in two cases of human hepatocellular carcinoma. The expression of c-N-ras, c-fos was greatly enhanced in tumor tissues of the two cases, and about 25%-50% of the tumor cells showed positive expression. The other three oncogenes namely c-K-ras, c-H-ras and c-myc, were not detected in these two carcinomas or the non-cancerous liver tissue adjacent to the carcinomas. It is surmised that c-N-ras and c-fos may play coordinative role in maintaining the malignant phenotype of human primary hepatocellular carcinoma.