The role of free radicals in normal and pathologic cell proliferation

Oxygen, while essential for life, is at the same time involved in the toxic effects of exposure to ionizing radiations, U.V. and a variety of chemical substances. All these cause an increased production of oxygen-derived free radicals (ODFR) and a modified pro-oxidant state. Many studies point to the involvement of the mechanisms controlled by ODFR in regulating the normal cell proliferation. In recent years, much evidence has been gathered implying the ODFR in the mechanisms of initiating and promoting the neoplastic transformations in vivo and in vitro, and in the activation of specific oncogenes.