Neuropilins – structure, function, role in cancerogenesis

Abstract

Neuropilins are proteins involved in ontogenesis, immunology and cancerogenesis. Neuropilin-1 and its homologue neuropilin-2 are coreceptors that intensify response to different growth factors and other ligands. They are coreceptors for class 3 semaphorines which are involved in axon growth and for a number of proteins belonging to VEGF family. Recently it has been discovered that their activity is much broader. They interact with TGF-β1 and its receptors, hepatocyte growth factor and its receptor, platelet derived growth factor and its receptors, fibroblasts growth factor and integrins. These ligands play a role in angiogenesis and wound healing. In immunology neuropilins are expressed mainly by dendritic cells and regulatory T lymphocytes and they apply mainly inhibitory effect. In neoplasms neuropilins are connected with a poor prognosis which is in accordance with their many interactions with ligands and receptors causing tumor progression.