Vitamin C and K3-Induced Oxidative Stress in Human Prostate Tumor Cells: Mitochondrial Ultrastructural Alterations.

Abstract Vitamins C (VC) and K3 (VK3) and a VC: VK3 combination with a VC: VK3 ratio of 100:1 were assayed for their antitumor activity against a DU 145 human prostate cancer cell line. Co-administration of the vitamins enhanced the antitumor activity 20-25 fold even with a lh exposure time. While exogenous catalase destroyed the antitumor activity, hydrogen peroxide-induced lipid peroxidation was negligible. The results of additional assays revealed: a transient increase in ATP production, a decrease in DNA synthesis, and increase in protein synthesis and a decrease in thiol levels. Subsequently the DU145 cells were treated with each vitamin alone or with the vitamin combination at their 50% cytotoxic doses and then examined using transmission electron microscopy. Treatment of DU145 cells with the vitamin combination exacerbated the cytotoxic effects induced by individual vitamin treatment. Untreated DU145 cells show numerous mitochondria whose pale matrices are in sharp contrast to the cytoplasmic background (Fig. 1).