The vascular endothelial cell growth factor family and its receptors:: Molecular and biological propertiES

Abstract

Angiogenesis is a multistep phenomenon that involves capillary endothelial cell proliferation, migration, and tissue infiltration. It plays a central role in a variety of physiological and pathological processes, such as embryonic development, wound healing, atherosclerosis, and tumor growth. Several factors that induce angiogenesis have recently been isolated and characterized. Among these are the acidic and basra form of fibroblast growth factor (FGF), both capable of stimulating capillary endothelial cell growth in vitro and being chemotactic FBR that cell type. In addition, both FGF isoforms stimulate extracellular proteolysis, which is believed to be an essential component of the angiogenic process. Numerous angiogenesis factors have been identified and characterized in the past ten years. The list includes tumor necrosis factor alpha (TNFα), transforming growth factor beta (TGFβ), transforming growth factor alpha (TGFα), epidermal growth factor (EGF) and interleukin-8 which are also angiogenic in vivo . However, with the exception of TGFot and EGF at high concentrations, these growth factors are not mitogenic for capillary endothelial cells. Their action on the angiogenic process is therefore probably indirect, resulting from such activities as attracting macrophages, which in turn release direct angiogenic factor(s), one of which could be basic FGF.