Au(iii)-Proline derivatives exhibiting selective antiproliferative activity against HepG2/SB3 apoptosis-resistant cancer cells

Abstract

This paper deals with the combination of a proline-based moiety with biologically active gold centers in the oxidation states +1 and +3. In particular, six Au(I)/(III)–proline dithiocarbamato (DTC) complexes with general formulae [Au^I₂(DTC)₂] and [Au^IIIX₂(DTC)] (X = Cl, Br) are reported here. After the synthesis of the ligand and the complexes, all derivatives were characterized via several techniques and tested for their stability in DMSO/water media. This study was focused on the demonstration of a peculiar behavior of Au(III)–DTC species in solution. Finally, the complexes were screened for their antiproliferative activity against 2 human cancer cell lines, namely HepG2 and HepG2/SB3, taken as models of hepatocellular carcinoma. The latter, chosen for its aggressiveness due to the upregulation of the anti-apoptotic protein SerpinB3, was selectively inhibited in terms of growth by some Au(III)–DTC complexes.