Anticancer activity of BIM-46174, a new inhibitor of the heterotrimeric Galpha/Gbetagamma protein complex

A large number of Hormones and local agonists activating guanine-binding protein-coupled receptors (GPCR) play a major role in Cancer progression. Here, we characterize the new imidazo-pyrazine derivative BIM-46174, which acts as a selective inhibitor of heterotrimeric G-protein complex. BIM-46174 prevents the heterotrimeric G-protein signaling linked to several GPCRs mediating (a) cyclic AMP generation (Galphas), (b) calcium release (Galphaq), and (c) Cancer cell invasion by Wnt-2 Frizzled receptors and high-affinity neurotensin receptors (Galphao/i and Galphaq). BIM-46174 inhibits the growth of a large panel of human Cancer cell lines, including Anticancer drug-resistant cells. Exposure of Cancer cells to BIM-46174 leads to caspase-3-dependent Apoptosis and poly(ADP-ribose) polymerase cleavage. National Cancer Institute COMPARE analysis for BIM-46174 supports its novel pharmacologic profile compared with 12,000 Anticancer agents. The growth rate of human tumor xenografts in athymic mice is significantly reduced after administration of BIM-46174 combined with either cisplatin, farnesyltransferase inhibitor, or Topoisomerase inhibitors. Our data validate the feasibility of targeting heterotrimeric G-protein functions downstream the GPCRs to improve Anticancer chemotherapy.