Combination of anti-angiogenic therapy and virotherapy: arming oncolytic viruses with anti-angiogenic genes.

Angiogenesis is essential for development and tissue repair, and is controlled by a balance of inhibitors and promoters. Overactive angiogenesis promotes tumor progression and other chronic disorders, including diabetic retinopathy and rheumatoid arthritis. The discovery of angiogenesis inhibitors has resulted in a promising therapeutic approach to these diseases. However, the benefits of anti-angiogenic drugs have been modest, stimulating interest in developing more effective approaches by combining anti-angiogenic therapy with other therapeutics. Oncolytic virotherapies are attractive therapeutics for cancer, but virotherapy alone has had similar problems to anti-angiogenic therapy, with few examples of clinical efficacy. This review summarizes the progress of the emerging field of combinations of anti-angiogenic therapy and virotherapy, and highlights future challenges in experimental and translational research that need to be addressed in order for these therapeutics to advance into the clinic.