This communication takes place, in part, through the secretion of angiogenesis factors such as vascular endothelial growth factor.

Preclinical studies Current clinical trials of angiogenesis factors were preceded by a large number of studies using animal models of cardiac or peripheral ischemia.

The mitogenic impulse gives rise to two factors, MDGF(Macrophage derived growth factor) and WAF (Wound angiogenesis factor).

Key determinants of metastatic behaviour include production growth and tumour angiogenesis factors; modulation of cell surface receptors and adhesion molecules; secretion of enzymes such as collagenase and plasminogen activator, and changes in the expression of MHC antigens.