Figure 3: Schematic illustration of non-ECM derived endogenous angioinhibitor signaling. Vasoinhibins: Bind probably prolactin receptor (PLR) and IL-1β. Inhibits Sos/Ras/MAPK, NOs/Raf/MAPK, and Ca2+/eNOs/ protein phosphatase 2 signaling. Promotes Ras/Tiam-1/Rac-1/Pak1 and Bcl-Xs mediated apoptosis.