Description
Endocrine Gland-Derived Vascular Endothelial Growth Factor (EG-VEGF) or Prokineticin-1 (PK-1) is a novel secreted protein expressed in various tissues including steroidogenic glands. Although structurally non-related to VEGF, EG-VEGF/PK-1 was shown to promote angiogenesis acting via two G-protein coupled receptors (PK-R1 and PK-R2).1 EG-VEGF is mitogen specific for the endothelium of steroidogenic glands. It induces proliferation, migration and fenestration in capillary endothelial cells derived from endocrine glands. EG-VEGF mRNA expression is localized to the steroid hormone-producing cells, i.e. Leydig cells of the testis and the specialized stroma in the ovary.2 EG-VEGF increased the phosphorylation of Akt in a phosphatidylinositol 3-kinase-dependent manner and is a survival factor for ACE cells. EG-VEGF, possibly through binding to a G-protein coupled receptor, results in the activation of MAPK p44/42 and phosphatidylinositol 3-kinase signaling pathways, leading to proliferation, migration, and survival of responsive endothelial cells