High induction of poly(ADP-ribose) polymerase activity in bleomycin-resistant HeLa cells.
Poly(ADP-ribose) polymerase activity was measured in bleomycin (BLM)-resistant HeLa (HeLa-BLMr) and the parental HeLa cells after BLM treatment. HeLa-BLMr cells, which had been subcultured in growth medium containing 1 micrograms/ml of BLM, showed a 3.75-fold higher enzyme activity than did HeLa cells, but this activity was decreased to the same level as that of HeLa cells after 48 h of BLM-free cultivation. When HeLa and HeLa-BLMr cells after a 48-h cultivation in BLM-free growth medium were treated with BLM, the enzyme activity was induced at a higher level (2.5-3.8 times) in HeLa-BLMr than in HeLa cells and was inhibited markedly in HeLa-BLMr and slightly in HeLa cells by nicotinamide, an inhibitor of this enzyme. The BLM-induced cell killing by nicotinamide was highly potentiated (about 18 times) in HeLa-BLMr as compared to HeLa cells.
Urade
M
M
First Department of Oral and Maxillofacial Surgery, Osaka University Faculty of Dentistry.
Sugi
M
M
Mima
T
T
Ogura
T
T
Matsuya
T
T
D001761:Bleomycin / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D004249:DNA Damage; D011088:DNA Ligases / Q000502:physiology; D004351:Drug Resistance; D004790:Enzyme Induction; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D009536:Niacinamide / Q000494:pharmacology; D011065:Poly(ADP-ribose) Polymerases / Q000096:biosynthesis*
D001761:Bleomycin; D009536:Niacinamide; D011065:Poly(ADP-ribose) Polymerases; D011088:DNA Ligases