Angiogenesis-related proteins--their role in the pathogenesis and treatment of inflammatory bowel disease.

The etiology of inflammatory bowel disease (IBD) is still not fully understood. Angiogenesis is one of the crucial phenomena sustaining chronic inflammation in the gastrointestinal tract. It has been also shown that the most potent anti-inflammatory drugs--anti-tumor necrosis factor alpha antibodies down-regulate intestinal angiogenesis, what is believed to contribute to their therapeutic efficacy. There are many proteins engaged in gastrointestinal angiogenesis, including pro-inflammatory cytokines, vascular growth factors, and adhesion molecules. Several of them are considered to be promising molecular targets for new drugs--monoclonal antibodies or fusion proteins. Here, we review new data highlighting the key role of proteins that regulate immune-mediated angiogenesis in IBD, like vascular endothelial growth factor, hypoxia inducible factor, angiopoietins, or basic fibroblast growth factor. We present the molecular mechanisms regulating the pathological proangiogenic activity in inflammatory conditions in IBD. We also discuss how new anti-cytokine regimens affect the function of angiogenesis-related proteins.