RGS5 and neoplasm: This hypothesis is reinforced with the recent work of Hamzah et al. using a genetically modified model of spontaneous pancreatic islet carcinoma in which the inactivation of Rgs5 (Regulator of G-protein signaling 5), a master gene controlling the aberrant morphology of tumor vasculature in mice and expressed by pericytes in the vascular bed, leads to normalization of tumors vessels (61).