TUMOR ANGIOGENESIS, A NEW TARGET FOR CANC ER-THERAPY

Angiogenesis is a complex pathophysiological process in which new vess els are formed from preexisting vessels. This neovascularization susta ins the progression of a number of pathological processes such as reti nopathies, rheumatoid arthritis, psoriasis and tumor metastasis. Numer ous studies have demonstrated that tumor progression to a metastatic s tate depends on the extent of neovascularization, leading to the sugge stion that inhibition of angiogenesis may result in a suppression of m etastases. A number of molecules that inhibit various aspects of the e ndothelial cell response to angiogenic stimuli have been developped an d are currently tested in clinical trials as novel anticancer drugs. T he results obtained so far showed that the antiangiogenic therapy may represent a highly effective approach to treat tumors that are refract ory to conventional cytotoxic therapy. Further studies directed at the molecular characterization of the mechanisms involved in tile activat ion of the endothelial cells by angiogenic stimuli and in its inhibiti on by antiangiogenic molecules thus represent a new approach to the st udy of cancer biology.