Angiogenesis inhibitors for the treatment of chronic autoimmune inflammatory arthritis

Angiogenesis, the formation of new blood vessels, is closely linked with both the initiation and progression of rheumatoid arthritis (RA). Rheumatoid joints contain elevated levels of proangiogenic molecules, such as VEGF, basic FGF, hypoxia-inducible factor 1 and angiopoietins. Increased angiogenesis is also associated with malignancies and proliferative retinopathies, and targeting this process therapeutically has proven beneficial in treating several of these diseases including colorectal, kidney and lung cancer. Adapting such a therapeutic strategy to the treatment of RA may prove beneficial, as data from preclinical studies have demonstrated that angiogenesis inhibitors reduce pannus formation, inflammation and joint erosion. New therapies that inhibit angiogenesis by blocking VEGFR tyrosine kinase signaling, integrin interactions, microtubule formation and endothelial cell proliferation may be applicable to the treatment of RA. There are several angiogenesis inhibitors that have been approved by the FDA or are currently being assessed in clinical trials which are safe for use in humans, although their effects on RA remain untested. This review discusses the potential of angiogenesis inhibition in the context of treating RA.