Fig. 2

G-protein-coupled receptors (GPCRs) participate in different physiological processes. The binding of ligands to GPCRs triggers a universal G protein allosteric mechanism that promotes the exchange of GDP with GTP on the α subunit of heterotrimeric G proteins. This event causes the dissociation of Gα from the dimer. Gα subunits mediate signals between GPCRs and intracellular signaling cascades. These signaling pathways include the PI3K/AKT/mTOR and MAPK/ERK pathways, both of which can mediate different biological processes, such as cell proliferation, migration and survival. Mutations in GPCRs and G proteins have been found at a very high frequency in tumor cells and endothelial cells in vascular anomalies