Transforming genes in human hepatomas detected by a tumorigenicity assay

Two transforming sequences in human hepatomas were detected by means of a tumorigenicity assay in nude mice using transfected NIH3T3 cells. Through hybridization with known oncogene probes, the transforming gene in one hepatoma was found to be the human hst gene. The transforming sequence in the other hepatoma showed no sequence homology with any of the oncogenes examined.