Angiogenesis and the fibrinolytic system.

Angiogenesis is defined as the formation of capillaries from preexisting blood vessels. This involves a balanced spatiotemporal modulation of endothelial cell adhesion, migration, and proliferation. An array of proteolytic enzymes expressed from endothelial cells including those of the plasminogen activator/plasmin system are required for angiogenesis to occur. In this review we focus on the growth factors that are involved in the angiogenic process and that modulate the expression and/or the activity of the plasminogen activator/plasmin system. The elucidation of the interactions between angiogenic growth factors, endothelial cell proteolytic enzymes, and the extracellular environment could ultimately lead to the therapeutic approaches to block angiogenesis and the pathophysiological conditions associated with it.