Interaction of promoters and oncogenes during transfection.

DNA transfection in recipient NIH3T3 mice cells is most widely used for identification of transforming genes in human tumor cells [1]. We showed earlier that c-Ha-ras proto-on-cogene from a human malignant glioma cell line (U 251 Mg) was active in transfection experiments. In primary U 251 Mg cells, c-Ha-ras gene was present in a single copy but amplified in transfected NIH3T3 cells [2].