Growth factor active in angiogenesis, and endothelial cell growth, stimulating their proliferation and migration and also has effects on the permeability of blood vessels. May function in angiogenesis of the venous and lymphatic vascular systems during embryogenesis, and also in the maintenance of differentiated lymphatic endothelium in adults. Binds and activates KDR/VEGFR2 and FLT4/VEGFR3 receptors. Homodimer; non-covalent and antiparallel. Interacts with FLT4/VEGFR3; the interaction is required for FLT4/VEGFR3 homodimarization and activation. Highly expressed in the lung, ovary, preputial gland and the adrenal gland. Expressed in the post-pubertal mammary glands. Increases moderately during pregnancy (2.8-fold increase on day 4) and lactation (1.9-fold increase on day 2). Undergoes a complex proteolytic maturation which generates a variety of processed secreted forms with increased activity toward VEGFR-3, but only the fully processed form could activate VEGFR-2. VEGF-C first form an antiparallel homodimer linked by disulfide bonds. Before secretion, a cleavage occurs between Arg-223 and Ser-224 producing a heterotetramer. The next extracellular step of the processing removes the N-terminal propeptide. Finally the mature VEGF-C is composed mostly of two VEGF homology domains (VHDs) bound by non-covalent interactions (By similarity). Indolinones; MAE87, MAE106 and MAZ51 inhibit VEGF-C induced activation of VEGFR-3. Belongs to the PDGF/VEGF growth factor family.