[Damages induced on DNA by oxygen-derived free radicals: pharmacological aspects]

Oxy-radicals can be generated at the cellular level by organic compounds displaying appropriated redox properties allowing one-electron transfer processes. Among the different molecules endowed with these properties, one can found a majority of cytotoxic antitumor agents whose mechanism of action involves the nuclear DNA degradation of the target cells. The nature of DNA damages produced by these antitumor agents using various experimental models is in agreement with the occurrence of oxy-radicals-mediated reactions. In most cases, a relationship between the redox properties and the action of these compounds at the molecular level is observed.