Is the Way to Fight Cancer Paved with Gold? Metal-Based Carbene Complexes with Multiple and Fascinating Biological Features

Abstract

Herein, we report the synthesis and the multiple anti-tumor properties of new gold and silver carbene complexes. The chemical modifications, grounded on our previous studies, led us to identify a good lead complex, gold-based, whose biological features are very exciting and promising in the anti-cancer research and could be further developed. Indeed, the bis-[4,5-dichloro-(<i>N</i>-methyl-<i>N</i>'(2-hydroxy-2-phenyl)ethyl-imidazole-2-ylidene)gold(I)]⁺[dichloro-gold]^- (<b>AuL7</b>) complex possesses the ability to interfere with at least three important and different intracellular targets, namely the human topoisomerases I and II and tubulin, which are able to modulate metabolic processes not directly correlated each other. We proved that the modifications of the ligands structure in <b>AuL7</b>, with respect to another already published complex, i.e., bis-[4,5-dichloro-(<i>N</i>-methyl-<i>N</i>'(cyclopentane-2ol)-imidazole-2-ylidine)gold(I)]⁺[dichloro-gold]^- (<b>AuL4</b>), produce a different behavior toward tubulin-polymerization process, since <b>AuL7 is</b> a tubulin-polymerization inhibitor and <b>AuL4</b> a stabilizer, with the final same result of hampering the tumor growth. Taken together, our outcomes designate <b>AuL7</b> as a promising compound for the development of multi-targeted anti-cancer therapies.