MET and neoplasm: Moreover, NRP1 was found to promote tumor progression via interacting with various extracellular growth factors and their receptors, including hepatocyte growth factor (HGF) and its receptor (cMet), fibroblast growth factors (FGFs), vascular endothelial growth factor (VEGF), transforming growth factor (TGF-β), etc 12, 20, 21.