Semaphorin 3B Gene Suppresses Tumor Growth Through the p53 Signaling Pathway and Neuropilin Receptors

The semaphorin family has been demonstrated to possess tumor suppressor activity; semaphorin 3B (SEMA3B) is differentially expressed in several types of tumors, and has been identified as a tumor suppressor gene. SEMA3B is shown to be a target gene of p53, and it suppresses tumor growth through the p53 signaling pathway. The mechanisms underlying tumor suppression by SEMA3B include neuropilin receptors (NRP1 and NRP2), which reduce the action of vascular endothelial growth factor (VEGF), thus, inhibiting tumor angiogenesis. Deficiency or down-regulation of SEMA3B expression can be found in a variety of malignant tumors including lung cancer, ovarian cancer, nervous system tumors, and hepatobiliary tumors, and this suppression involves methylation, loss of heterozygosity (LOH) and enzyme cleavage. This review summarizes recent research approaches on the tumor suppression effects and mechanisms of SEMA3B.