Angiogenesis: a therapeutic target in arthritis.

A variety of pharmacological strategies are being subjected to clinical trial to inhibit neovascularization of solid tumors. Increased angiogenesis is also a key component of synovitis and bone modeling in arthritis. Molecular mechanisms and pathological consequences of blood vessel growth in arthritis are now being elucidated. Preclinical studies of angiogenesis inhibitors in animal models of inflammatory arthritis support the hypothesis that inhibition of neovascularization may reduce inflammation and joint damage. Clinical data are consistent with these models being predictive of efficacy in rheumatoid arthritis. However, controlled studies of specific anti-angiogenic agents in human arthritis remain limited. Further studies are required to demonstrate that pharmacological agents can effectively inhibit articular angiogenesis, and ameliorate inflammation and subsequent joint damage. Potential toxicity of angiogenesis inhibitors in reproduction, growth and development and wound repair may be circumvented by short-term or local application, or by targeting molecular mechanisms that are specific to pathological rather than physiological angiogenesis.