12-o-tetradecanoylphorbol 13-acetate ( tpa ) , a known tumor promoter , enhances the morphologic transformation of syrian hamster embryo cells induced by low transforming concentrations of n-methyl-n'-nitro-n-nitrosoguanidine ( mnng ) ( 0.025-0.1 microgram/ml ) without potentiation of cell lethality or of changes in sister chromatid exchanges ( sces ) or chromosomal aberration frequencies .
C0007634
cell
C0037211
sister chromatid exchanges