Additionally, it has been established that endoglin counterbalances the steadying function of ALK5 [46, 47]. ACVRL1 and ENG mutations disturb TGF-β/BMP signaling, thus modifying pericyte recruitment and EC tubulogenesis triggering irregular capillary maturation and formation leading to vascular hyperbranching, AVMs, and venous expansion elucidating the irregular morphogenesis of vascular in HHT [13, 48]. Here, ACVRL1 is linked to hereditary hemorrhagic telangiectasia.