Reversible expression of morphological transformation in C3H/10T1/2 mouse embryo cultures exposed to 12-O-tetradecanoylphorbol-13-acetate.

Treatment of C3H/10T1/2 mouse embryo fibroblasts with N-methyl-N'-nitro-N-nitrosoguanidine and then 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in the production of numerous foci of morphologically transformed cells. When dishes containing foci were provided medium which did not contain TPA, up to 84% of the foci were found to regress. Promotion of morphological transformation by TPA in C3H/10T1/2 cells may thus be a reversible process.