VEGFA and rheumatoid arthritis: These cytokines exert pro-angiogenic effects in RA both through their direct effect on ECs (meaning the response of ECs to the cytokine results in new vessel formation) as well as their indirect effect (by subsequent release of factors that induce endothelial cells angiogenesis) in the inflamed RA synovium producing pro-angiogenic factors including vascular EC growth factor (VEGF) [10,16,17].