Fibrinogen E-fragment inhibits the migration and tubule formation of humandermal microvascular endothelial cells in vitro

Angiogenesis, the development of new blood vessels from an existing vascula r bed, is essential for the growth and spread of malignant tumors. Several endogenous angiogenesis inhibitors have been discovered and shown to suppre ss endothelial cell function in vitro and tumor growth in vivo. Several of these are proteolytic fragments of larger, endogenous proteins. Here we sho w that a M-r 50,000 polypeptide derived from the plasmin cleavage of fibrin ogen, fibrinogen E-fragment, inhibits endothelial cell migration and tubule formation induced by both proangiogenic growth factors, vascular endotheli al growth factor and basic fibroblast growth factor, in vitro.