Angiogenesis and breast cancer

The growth of breast cancers, as is the case in other solid tumors, is dependent on the development of neo-vessels, This has been clearly demonstrated in preclinical models and clinical-biological studies. Yet, the biological mechanisms involved in angiogenesis are heterogeneous; pathways activated by vascular endothelial growth factor (VEGF) seem to play a prominent role in the early stages of the disease, whereas a number of other pathways are involved in the development of progressive and metastatic tumors. This might account for the disappointing results of phase III studies of bevacizumab in breast cancer as compared with results reported in renal or colon cancers. The use of new drugs targeting other angiogenic factors and a better selection of patients eligible for treatment might improve these results. This is a review of the major biological and clinical data available on the critical role of angiogenesis in breast cancer. We will also review the different clinical studies reported to date in this area.