Role of intracellular accumulation in the prooxidant cytotoxicity of daunorubicin

Abstract

Oxidative stress partly contributes to the cytotoxicity of the anticancer anthracycline daunorubicin in FLK and HL-60 cells. However, daunorubicin is 100–300 times more cytotoxic than the model quinone danthron possessing a similar reduction potential. This discrepancy may be explained by the high cell/medium partition coefficient of daunorubicin, 570 ± 40 (HL-60 cells) and 230 ± 30 (FLK cells) calculated using the fluorescence quenching method. The cell/medium partition coefficient for danthron is below 10. Keywords: daunorubicin, intracellular accumulation, cytotoxicity, oxidative stress