FLT1 and neoplasm: Production of VEGFs, especially VEGF-A, VEGF-C and VEGF-D, and their receptors VEGFR-1, VEGFR-2 and VEGFR-3 trigger changes in endothelial cell proliferation, support formation of de novo blood vessels and vascular permeability at different tumour sites, to allow a higher degree of tumour cell survival and distal metastases.