CYTOTOXIC AND ANTIPROLIFERATIVE ACTIVITIES OF COBALT (II) COMPLEXES WITH DIFFERENT LIGANDS ON CULTURED TUMOR CELLS

Cobalt is one of the most important trace elements in the world of animals and humans. Various cobalt containing compounds have been reported to express antineoplastic properties. The aim of this study was to evaluate the influence of 19 newly synthesized cobalt (II) complexes with different ligands (aminoacids, cholic acids, Mannich bases, mixed ligands) on cultured tumor cells. The following model systems were used in the experiments: 1) Permament cell lines from human (carcinoma of the larynx Hep-2, rhabdomyosarcoma RD64, glioblastoma multiforme 8 MG BA, breast cancer MCF-7 and erythroleukemia K562), rat (transplantable sarcoma induced by Rous sarcoma virus strain Schmidt-Ruppin), murine (myeloma P3U1) and chicken (transplantable hepatoma induced by the myelocytomatosis virus Mc29) origin; 2) primary cultures from myeloid tumor in hamster induced by Graffi mouse leukemia virus. The influence of the compounds on cell viability and proliferation as well as cytopathological changes were studied by MTT test, neutral red uptake cytotoxicity assay, colony-forming method, autoradiography, neutral and alkaline variants of single cell gel electrophoresis and acridine orange staining. The results obtained revealed that the compounds tested express time- and concentration-dependent cytotoxic and antiproliferative activities. The compounds with the most promising antitumor properties were found among the complexes with mixed ligands 2-hydroxy-benzophenones and nitrogenous bases enR. Some of them were found to reduce cell viability by 50% (IC sub(50)) when applied at concentrations