Vascular endothelial growth factor receptor 3 (VEGF R3), also known as Flt-4, is a tyrosine kinase receptor for VEGF-C and VEGF-D. The protein is thought to be involved in lymphangiogenesis and maintenance of the lymphatic endothelium. In lymphoma patients, high expression of VEGF R3 can been found in lymph endothelial cells isolated from the tumor tissue.
Mutations in this gene cause hereditary lymphedema type IA. Several studies have shown positive correlations between VEGF-C, VEGF-D and VEGF R3 expression and vascular invasion, lymphatic vessel and lymph node involvement. The VEGF-C/VEGF-D/VEGFR3 signaling pathway may provide a target for antilymphangiogenic therapy in prostate cancer, breast cancer, gastric cancer, lung cancer, non-small cell lung cancer, and so on.