The important secretion of VEGF by tumor cells 1) suppresses PDGFRβ (platelet-derived growth factor receptor beta) signaling in vascular smooth muscle cells via the complexation of PDGFRβ and VEGFR2 that assemble into a hybrid receptor, and 2) modulates the activity of GTPases like RhoA with the effect of increasing vascular permeability (20, 21). This evidence concerns the gene PDGFRB and neoplasm.