Role of angiogenesis in the response to anticancer therapies

Most solid tumors develop a vasculature (angiogenesis) as they increase in mass. Elucidation of the process by which blood vessels form in tumors has revealed the existence of both positive and negative regulators produced and secreted by many cell types. Angiogenesis has been identified as a critical process in mass expansion in most solid tumors, and numerous molecules have been described to be antiangiogenic agents. The question of whether antiangiogenic therapy is compatible with cytotoxic anticancer therapy has been addressed in the Lewis lung tumor with TNP-470 and minocycline along with radiation therapy and chemotherapy. Although the antiangiogenic therapy had no effect on the tumor size, administration of TNP-470/minocycline increased drug delivery to the tumor and tumor response to cytotoxic therapy increased implicating a potential role for these agents in the treatment of solid tumors.