[Expression of cellular oncogenes in human hepatocellular carcinoma cell line BEL 7402 and the effect of sodium butyrate on the expression of cellular oncogenes].

With dot blot and cytoplasmic hybridization techniques we found that the c-Ha-ras, c-Ki-ras, c-N-ras, c-myc and c-fos oncogenes were over-expressed in human hepatocellular carcinoma cell line BEL 7402 cells. The mRNA expression of c-Ha-ras, c-Ki-ras, c-N-ras and c-myc oncogenes could be inhibited by 2 mmol/L sodium butyrate treatment, but this had no effect on the expression of c-fos. However, the mRNA expression of c-Ha-ras, c-N-Ras and c-myc oncogenes was enhanced by 4 mmol/L sodium butyrate treatment, while the expression of c-Ki-ras and c-fos remained unchanged. No significant effect on the expression of carbamyl phosphate synthetase I, a tissue-specific enzyme associated with the differentiation of liver cells, was observed by 2 mmol/L or 4 mmol/L sodium butyrate treatment of the hepatoma cells.