[Angiogenic inhibitors and radiotherapy: from the concept to the clinical trial]

Increasing studies show the central role of the tumor microenvironment, and more particularly the angiogenesis, in the response to anticancer treatment such as radiotherapy. Thus the association of angiogenesis inhibitors to radiotherapy is a strategy whose concept is based on several mechanisms of actions, such as the implication of the angiogenic factors in the control of tumor radiosensitivity, the regulation of the tumor radiosensitivity by that of the endothelial cells, the induction of hypoxia by the tumor angiogenesis, the induction of HIF-1alpha by irradiation and finally the importance of the angiogenic factors in the tumor stem cells survival, known to be radioresistant. These mechanisms will be detailed in this article as well as several clinical trials associating these inhibitors with radiotherapy.