TUMOR ANGIOGENESIS - THE PIVOTAL ROLE OF VASCULAR ENDOTHELIAL GROWTH-FACTOR

There is considerable evidence that vascular endothelial growth factor is involved in the vascularization and growth of primary tumors and i n the formation of metastases. The expression of vascular endothelial growth factor depends on activated oncogenes and inactivated tumor-sup pressor genes as well as several other factors, e.g., growth actors, h ypoxia, and tumor promoters. Substantial expression of vascular endoth elial growth factor receptors is mainly restricted to tumor vessels. T he causal involvement of this angiogenic factor in the progression of the disease has been successfully evaluated using monoclonal antibodie s against vascular endothelial growth factor, dominant negative recept or mutants, and antisense oligonucleotides against the messenger RNA o f vascular endothelial growth factor Thus, the vascular endothelial gr owth factor-signaling system seems to be an appropriate target for inh ibition of tumor angiogenesis and metastasis formation.