Vascular endothelial growth factor (VEGF) represents a growth factor with important pro-angiogenic activity, having a mitogenic and an anti-apoptotic effect on endothelial cells, increasing the vascular permeability, promoting cell migration, etc. VEGF binds to tyrosine kinase cell receptors (VEGFRs): VEGFR-1 [Fms-like tyrosine kinase 1 (Flt-1)], VEGFR-2 [kinase insert domain receptor (KDR) in human; fetal liver kinase 1 (Flk-1) in mouse] and VEGFR-3 [Fms-like tyrosine kinase 4 (Flt-4)]. While VEGFR-1 and VEGFR-2 are expressed predominantly on vascular endothelial cells, VEGFR-3 is expressed especially on lymphatic endothelial cells [PMID: 30173249].