Scaldaferri et al. extracted intestinal samples from patients with IBD and controls and measured the expression levels of vascular endothelial growth factor-A (VEGF-A) and its receptors VEGFR-1 and VEGFR-2 well as the induction of VEGF-A in human intestinal microvascular endothelial cells angiogenesis. This evidence concerns the gene KDR and inflammatory bowel disease.