Selectivity of effects of redox-active cobalt (III) complexes on tumor tissue

Abstract

Aim: To estimate the selectivity of action of cobalt complexes on tumor tissue. Materials and Methods: Cobalt (III) complexes containing both the tetradentate Schiff-base ligand derived from acetylacetone and ethylenediamine, and compounds of the vitamin PP series or their synthetic analogs, viz. nicotinamide, isonicotinamide or nicotinic acid, as extra (axial) ligands, were tested in vivo on transplanted mice tumors, namely Lewis lung carcinoma (3LL), melanoma B16, and mammary adenocarcinoma Ca755. Concentrations of malondialdehyde in tissue extracts were measured by standard biochemical methods. The rate of DNA unwinding was used to detect DNA damage in tumor cells. Level of tumor hypoxia as well as bioenergetic status were estimated using 31P NMR spectroscopy in perchloric acid extracts of tissue. Results: A significant and selective increase of …