Synthesis, Characterization, and Comparative in Vitro Cytotoxicity Studies of Platinum(II), Palladium(II), and Gold(III) Methylsarcosinedithiocarbamate Complexes

This work reports on the synthesis, characterization, and in vitro cytotoxic activity of some new platinum(II), palladium(II), and gold(III) derivatives of methylsarcosinedithiocarbamate and its S-methyl ester, to study their behavior as potential antitumor agents. The biological activity of these compounds, as determined by growth inhibition and apoptosis induction, has been investigated in both human leukemic promyelocites HL60 and human squamous cervical adenocarcinoma HeLa cell lines, and their activity has been compared to the well-known platinum-based anticancer agent cisplatin. On the basis of these experimental results, [Pd(MSDT)X]n (MSDT = methylsarcosinedithiocarbamate; X = Cl, Br) complexes show a strong dose-dependent growth inhibition of both HL60 and HeLa cells, with IC50 values slightly higher than those recorded for cisplatin; moreover, [Au(MSDT)X2] activity appears significantly higher or, at least, comparable to that of the reference drug. Exposure of both cell lines to [Pd(MSDT)X]n and [Au(MSDT)X2] complexes induces apoptosis, as determined by an Apo2.7 assay

Gold Dithiocarbamate Derivatives as Potential Antineoplastic Agents: Design, Spectroscopic Properties, and in Vitro Antitumor Activity

At present, cisplatin (cis-diamminodichloroplatinum(II)) is one of the most largely employed anticancer drugs as it is effective in the treatment of 70−90% of testicular and, in combination with other drugs, of ovarian, small cell lung, bladder, brain, and breast tumors. Anyway, despite its high effectiveness, it exhibits some clinical problems related to its use in the curative therapy, such as a severe normal tissue toxicity (in particular, nephrotoxicity) and the frequent occurrence of initial and acquired resistance to the treatment. To obtain compounds with superior chemotherapeutic index in terms of increased bioavailability, higher cytotoxicity, and lower side effects than cisplatin, we report here on some gold(I) and gold(III) complexes with dithiocarbamate ligands (DMDT = N,N-dimethyldithiocarbamate; DMDTM = S-methyl-N,N-dimethyldithiocarbamate; ESDT = ethylsarcosinedithiocarbamate), which have been synthesized, purified, and characterized by means of elemental analyses, conductivity measurements, mono- and bidimensional NMR, FT-IR, and UV−vis spectroscopy, and thermal analyses. Moreover, the electrochemical properties of the designed compounds have been studied through cyclic voltammetry. All the synthesized gold complexes have been tested for their in vitro cytotoxic activity. Remarkably, most of them, in particular gold(III) derivatives of N,N-dimethyldithiocarbamate and ethylsarcosinedithiocarbamate, have been proved to be much more cytotoxic in vitro than cisplatin, with IC50 values about 1- to 4-fold lower than that of the reference drug, even toward human tumor cell lines intrinsically resistant to cisplatin itself. Moreover, they appeared to be much more cytotoxic also on the cisplatin-resistant cell lines, with activity levels comparable to those on the corresponding cisplatin-sensitive cell lines, ruling out the occurrence of cross-resistance phenomena and supporting the hypothesis of a different antitumor activity mechanism of action

Chemical and Biological Profiles of Novel Copper(II) Complexes Containing S-Donor Ligands for the Treatment of Cancer

In the last years, we have synthesized some new platinum(II), palladium(II), gold(I/III) complexes with dithiocarbamato derivatives as potential anticancer drugs, to obtain compounds with superior chemotherapeutic index in terms of increased bioavailability, higher cytotoxicity, and lower side effects than cisplatin. On the basis of the obtained encouraging results, we have been studying the interaction of CuCl2 with methyl-/ethyl-/tert-butylsarcosine-dithiocarbamato moieties in a 1:2 molar ratio; we also synthesized and studied the N,N-dimethyl- and pyrrolidine-dithiocarbamato copper complexes for comparison purposes. The reported compounds have been successfully isolated, purified, and fully characterized by means of several spectroscopic techniques. Moreover, the electrochemical properties of the designed compounds have been studied through cyclic voltammetry. In addition, the behavior in solution was followed by means of UV−vis technique to check the stability with time in physiological conditions. To evaluate their in vitro cytotoxic properties, preliminary biological assays (MTT test) have been carried out on a panel of human tumor cell lines. The results show that cytotoxicity levels of all of the tested complexes are comparable or even greater than that of the reference drug (cisplatin)