SEMA3B

Semaphorin-3B (SEMA3B), also known as SEMAIVB, is a secreted semaphorin family member. It acts via binding to neuropilin-1 (NRP1) and plexin A co-receptors, regulating axon guidance in neural development. As a tumor suppressor, it induces caspase-dependent apoptosis, inhibits cell proliferation/migration, and suppresses angiogenesis by targeting endothelial cells.
Downregulation of SEMA3B via promoter hypermethylation is common in lung, breast, and colorectal cancers, linked to poor prognosis. While direct therapeutics targeting SEMA3B are preclinical, demethylating agents (e.g., 5-azacytidine derivatives) show promise in restoring its expression in cancer cells, reactivating tumor-suppressive functions.