Radiation-induced antitumor properties of vitamin B5 (pantothenic acid) and its effect on mitomycin C activity: experiments in vitro.

Vitamin B5 (pantothenic acid) shows a strongly pronounced antitumor effect under the influence of ionizing radiation. In the frame of experiments in vitro (model: Escherichia coli bacteria, AB1157) performed under the exact knowledge of concentration and kind of the free radicals acting in the various aqueous media (pH 7.4) the following was established: (i) vitamin B5 possesses a very intense antitumor property, (ii) it exerts a strong synergistic effect on mitomycin C (MMC), (iii) the oxidizing species (OH*, O2*-) appears to be most important in the initiation of the observed effect. The generated radiolytic products from vitamin B5 very likely also play an important role in this respect.