Endopeptidases are the first example and have been implicated in the biosynthesis of Ang-(1–7) mainly from Ang I. As an example, prolyl endopeptidase converts Ang I into Ang-(1–7) as shown in NG108-15 neuroblastoma versus glioma hybrid cells [23] and in endothelial cells from human and bovine aorta as well as in umbilical veins [24]. This evidence concerns the gene ANG and central nervous system cancer.