Vascular endothelial growth factor receptor (VEGFR) is the receptor for VEGF. VEGF is an important signaling protein involved in both vasculogenesis and angiogenesis. VEGFRs consist of three subtypes, the fms-like tyrosine kinase Flt-1 (VEGFR1/Flt-1), the kinase domain region, also referred to as fetal liver kinase (VEGFR2/KDR/Flk-1), and Flt-4 (VEGFR3)....