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

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