Organotin(IV) complexes with epigenetic modulator ligands: New promising candidates in cancer therapy

Organotin(IV) compounds have found their place among a class of non-platinum chemotherapeutic metallo-pharmaceuticals exhibiting good antitumor activity. The cytotoxicity induced by the different kinds of organotins has been related to several mechanism. In this review we report our last decade research activity concerning the synthesis and chemical characterization of new organotin(IV) derivatives containing epigenetic modulator ligand by using, FT-IR, Mössbauer spectroscopy, 119Sn{1H} cross polarization magic angle spinning, electrospray ionization mass spectroscopy, UV–Vis, 1H, 13C{1H} and 119Sn{1H} NMR spectroscopy and density functional theory calculations. The first aim of the biological studies was to evaluate the effects exerted by organotin(IV) complexes in comparison with corresponding free ligands on a panel of different cancer cell lines, including human HepG2 hepatoma cells, HCT116 colorectal carcinoma cells and MDA-MB-231 breast cancer cells. We provide evidence that the compounds, generally, exert significant cytotoxic activity in cancer cells even at nanomolar (nM) or micromolar (μM) range concentrations. We also evaluated the biochemical pathways underlining these effects and the epigenetic activity of the compounds in the coordinated form compared to their parental constituents.