Angiopoietin-1 and Angiopoietin-2 (Ang-1 and Ang-2)

Angiopoietin-1 and Angiopoietin-2 are secreted glycoprotein growth factors that play essential and opposing roles in vascular biology. Both serve as primary ligands for the Tie2 (tyrosine kinase with immunoglobulin-like and EGF-like domains 2) receptor expressed on endothelial cells[1][5][7]. Angiopoietin-1 (Ang-1) promotes vascular maturation, stabilization, and endothelial cell survival, supporting vessel quiescence and integrity[7][3][5]. Angiopoietin-2 (Ang-2) generally antagonizes Ang-1, destabilizing blood vessels and enhancing their responsiveness to angiogenic signals such as VEGF, especially under pathological or inflammatory conditions; Ang-2 thus facilitates vascular leakage, regression, remodeling, and neovascularization[1][2][3][5]. The Ang/Tie2 pathway is of major clinical relevance in cancer, retinal diseases, and other vascular disorders, making Ang-1 and Ang-2 active therapeutic targets, with both anti-angiogenic and vascular stabilizing agents in development and clinical study[6][4][8].

Other names

Angpt1 (Angiopoietin-1)Angpt2 (Angiopoietin-2)ANGPT1ANGPT2

Inhibition of Ang-1/Ang-2 blocks their interaction with the Tie2 receptor and modulates downstream signaling to suppress angiogenesis and vascular destabilization (e.g., Trebananib sequesters Ang-1/Ang-2, preventing activation of Tie2)[8][6] - Dual Ang-2/VEGF inhibition: reduces neovascularization, vascular leakage, and inflammation[2][6]