Effects of protein kinase inhibitors on radiation-induced WAF1 accumulation in human cultured melanoma cells.
To examine whether protein kinase C (PKC) and A (PKA) contribute to WAF1 induction by ionizing radiation (IR) in cultured human melanomas, the effect of PK inhibitors 1-(5'-isoquinolinesulphonyl)-2-methylpiperazine dihydrochloride (H7), bisindolylmaleimide (GF) and N-[2(p-dromocinnamylamino)ethyl]-5-isoquinolinesulphonamide (H89) on IR-induced WAF1 accumulation was analysed by Western blot analysis. Gamma-ray-induced accumulation of WAF1 showed a peak at 6 Gy in all the cell lines. After gamma-ray irradiation of 6 Gy, a peak of WAF1 accumulation was observed at 6 h in SK-Mel-26, G361 and HM6KO cells, and at 3 h in MeWo cells. In MeWo and SK-Mel-26 cells, the X-ray-induced WAF1 accumulation was decreased by PK inhibitors, GF (PKC inhibitor) or H89 (PKA inhibitor); this did not occur in G361 and HM6KO. In all the cell lines, accumulation of WAF1 induced by X-ray irradiation was suppressed by H7 (PKC and PKA inhibitor). In addition, polymerase chain reaction-single strand conformational polymorphism analysis detected no aberrations in the p53 gene of the four cell lines used. These results suggest that IR-induced WAF1 expression involves PKC and/or PKA activity depending on cell type.
Fujino
M
M
Department of Dermatology, University of Occupational and Environmental Health, Yahatanisi-ku, Kitakyusyu, Fukuoka 807-8555, Japan.
Ohnishi
K
K
Asahi
M
M
Wang
X
X
Takahashi
A
A
Ohnishi
T
T
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000494:pharmacology; D015153:Blotting, Western; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000032:analysis / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D004791:Enzyme Inhibitors / Q000378:metabolism / Q000494:pharmacology*; D005720:Gamma Rays; D006801:Humans; D007546:Isoquinolines / Q000494:pharmacology; D018807:Polymorphism, Single-Stranded Conformational; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D047428:Protein Kinase Inhibitors; D015398:Signal Transduction; D013449:Sulfonamides; D014407:Tumor Cells, Cultured / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000378:metabolism
C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D007546:Isoquinolines; D047428:Protein Kinase Inhibitors; D013449:Sulfonamides; D016159:Tumor Suppressor Protein p53; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide