The effect of anoxia on anthracycline-induced DNA damage in the RPMI-6410 human lymphoblastoid cell line.
The alkaline elution procedure developed by Kohn and co-workers was used with the RPMI-6410 cultured human lymphoblastoid cell line to examine the hypothesis that anthracycline-induced DNA strand scission is mediated by oxygen- or superoxide-derived free radicals. Hypoxia was induced by gassing with nitrogen containing 5% carbon dioxide and less than 4 ppm oxygen. Alkaline elution studies showed hypoxia was induced, as the oxygen enhancement ratios for DNA strand breaks was 2.4 and 2.6 for the 250 R +/- oxygen and the 500 R +/- oxygen (1 R = 2.58 x 10(-4) C/kg) experiments, respectively. The pattern of adriamycin-induced DNA strand breaks and cross-linking was not affected by hypoxia with 1-h adriamycin exposures between 0.05 and 1.0 microgram/ml. Similarly, 1-h exposures of N-trifluoroacetyladriamycin-14-valerate at 3 or 10 micrograms/mL gave essentially identical alkaline elution profiles in the presence or absence of oxygen. These results do not support the hypothesis that oxygen-derived radicals play a primary role in anthracycline-induced DNA strand breakage.
D000468:Alkalies; D000903:Antibiotics, Antineoplastic; D002460:Cell Line; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA / Q000302:isolation & purification*; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects*; D009279:Naphthacenes / Q000494:pharmacology; D010100:Oxygen / Q000494:pharmacology*
D000468:Alkalies; D000903:Antibiotics, Antineoplastic; D009279:Naphthacenes; D004247:DNA; D010100:Oxygen