Activation of N-ras gene in a rat hepatocellular carcinoma induced by dibutylnitrosamine and butylated hydroxytoluene.

DNA samples from eighteen rat hepatocellular carcinomas, including those induced by oral administration of dibutylnitrosamine (DBN) with butylated hydroxytoluene (BHT), or DBN with butylated hydroxyanisole (BHA), have been tested for the presence of transforming activity by transfection assay with NIH3T3 cells. Of the eighteen samples, only one from a tumor induced by DBN and BHT gave transformants. the activated oncogene was identified as rat N-ras by Southern blot analysis.