VEGF is the acronym for "Vascular Endothelial Growth Factor". VEGF is a family of proteins that act as signal molecules and perform important tasks in the vascularisation (vasculogenesis, angiogenesis of blood and lymph vessels) of tissue. The VEGF family includes VEFG-A (the first member of this family to be discovered and researched), as well as the subtypes B,C,D . VEGF-C and VEGF-D serve the development of lymph vessels. VEGFs are formed by a variety of tissue cells, but also by immune cells. VEGF-A in particular stimulates the growth of new blood vessels by triggering the formation of growth factors after binding to a VEGF receptor on the endothelial cells. It is found in all vascularized tissues.
VEGF-C also acts as a growth factor that stimulates the growth of lymphatic vessels (lymphangiogenesis) and, under certain circumstances, blood vessels (angiogenesis). VEGF-C binds to the receptors VEGFR-2 or VEGF-3 and causes activation of the downstream signalling cascades. Besides these effects, VEGF-C is also involved in the development of the nervous system and the regulation of blood pressure.
As far as its function is concerned, only very vague ideas exist so far. It is assumed that VEGF-C, like VEGF-D, plays a role in tumour angiogenesis and lymphatic metastasis.
In some patients with hereditary lymphedema type I, a mutated VEGF-C gene is the cause of the disease. In this case, a deficiency of VEGF-C causes lymphoedema.
The development of a VEGF-C-containing drug (Lymfactin) seems to improve the lmyphedema.