NRP1 and neoplasm: NRP1 could promote tumor metastasis through several mechanisms, such as facilitate endothelial cell migration induced by VEGF 22-24, boost the migration and proliferation of tumor cells through autocrine Semaphorin 3A (Sema 3A) 25 and HGF/SF signaling 26, stimulate tumor growth by increasing fibronectin fibril assembly in the tumor microenvironment 27, uphold dedifferentiation and propagation phenotypes of cancer cells 28, maintain the properties of cancer stem cells 29, and induce tumor immunosuppression signaling 8, 30.