BMP9, but not BMP10, acts as a quiescence factor on tumor growth, vessel normalization and metastasis in a mouse model of breast cancer

Background Angiogenesis has become an attractive target for cancer therapy. However, despite the initial success of anti-VEGF (Vascular endothelial growth factor) therapies, the overall survival appears only modestly improved and resistance to therapy often develops. Other anti-angiogenic targets are thus urgently needed. The predominant expression of the type I BMP (bone morphogenetic protein) receptor ALK1 (activin receptor-like kinase 1) in endothelial cells makes it an attractive target, and phase I/II trials are currently being conducted. ALK1 binds with strong affinity to two ligands that belong to the TGF-s family, BMP9 and BMP10. In the present work, we addressed their specific roles in tumor angiogenesis, cancer development and metastasis in a mammary cancer model.