title: Tumor promoter 12-O-tetradecanoylphorbol 13-acetate stimulates simian virus 40 induction by DNA-damaging agents and tumor initiators.
abstract: Simian virus 40 (SV40)-transformed Syrian hamster kidney cells produce infectious SV40 virus particles after treatments which damage DNA, such as UV irradiation or mitomycin C treatment. We have found that the induction of SV40 by DNA-damaging agents is greatly stimulated when a typical tumor promoter, 12-O-tetradecanoylphorbol 13-acetate (TPA), is present in the medium. Phorbol, which has a molecular structure similar to TPA but does not have any tumor-promoting activity, showed no such stimulatory effect on SV40 induction. This apparent synergistic effect of DNA-damaging agents and tumor promoter (TPA) was more pronounced when a tumor initiator, benzo [a]pyrene or 2-acetamido-fluorene, was combined with TPA. The effect of TPA on UV-triggered SV40 induction was greatly influenced by the timing of TPA addition to the culture medium, which was most efficient when addition of TPA was 5 to 20 h before UV irradiation. The effect of TPA, however, was not observed in SV40 rescue from hamster cells by cell fusion with permissive monkey (C7) cells.
mesh_terms: D015073:2-Acetylaminofluorene / Q000494:pharmacology; D000818:Animals; D001564:Benzo(a)pyrene; D001580:Benzopyrenes / Q000494:pharmacology; D002478:Cells, Cultured; D006224:Cricetinae; D008647:Mesocricetus; D016685:Mitomycin; D008937:Mitomycins / Q000494:pharmacology; D010704:Phorbols / Q000494:pharmacology*; D013539:Simian virus 40 / Q000187:drug effects* / Q000254:growth & development; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014466:Ultraviolet Rays; D014775:Virus Activation / Q000187:drug effects* / Q000528:radiation effects
chemical_list: D001580:Benzopyrenes; D008937:Mitomycins; D010704:Phorbols; D001564:Benzo(a)pyrene; D016685:Mitomycin; D015073:2-Acetylaminofluorene; D013755:Tetradecanoylphorbol Acetate; C033085:phorbol