Tumoral angiogenesis and breast cancer.

Breast cancer (BC) is the most common neoplasm in women in Western countries. Tumoral angiogenesis (TA) is essential for the growth and spread of BC cells. There are at least 6 different angiogenic growth factors associated with TA in BC. The major mediator of TA is vascular endothelial growth factor (VEGF), a homodimeric heparin-binding glycoprotein. VEGF signals through VEGF receptor-2 (VEGFR-2), the major VEGF signalling receptor that mediates sprouting angiogenesis. Recently, different antiangiogenic agents have shown efficacy in the treatment of advanced BC. Bevacizumab, a humanised monoclonal antibody against VEGF, in combination with taxanes improves progression-free survival and overall response rate in first-line therapy. Other new antiangiogenic agents, called multi-kinase inhibitors (sunitinib and pazopanib), are under investigation. Finally, a schedule of treatment called metronomic chemotherapy, with antiangiogenic activity, has also demonstrated efficacy in the treatment of advanced BC.