Brain expressed X-linked protein 4 (BEX4)

Brain expressed X-linked protein 4 (BEX4) is a member of the BEX gene family, notable for roles in regulating cell cycle progression, mitosis, and the acetylation state of microtubule proteins. BEX4’s function is highly context-dependent: it can act as a tumor suppressor or as an oncogene depending on cell type and disease state. In cancers such as oral squamous cell carcinoma, BEX4 is often epigenetically silenced and suppresses tumor growth when re-expressed, whereas in glioblastoma and lung adenocarcinoma BEX4 is overexpressed, promoting cell proliferation, resistance to apoptosis, and tumor progression through modulation of mitotic fidelity and microtubule acetylation (notably via SIRT2 inhibition). Lower BEX4 levels are associated with poor prognosis in some cancers, and high expression serves as a prognostic biomarker in glioblastoma and gastric cancer. No approved drugs directly target BEX4, but its regulatory roles—especially in microtubule dynamics and cell division—suggest relevance as a future cancer therapeutic target, with important safety concerns stemming from its dual and opposing effects in different tissues and cancer types.

Other names

BEXL1NADE3FLJ10097BEX1-like protein 1Brain-expressed X-linked protein 4Nerve growth factor receptor-associated protein 3BEX family member 4brain expressed X-linked-like 1BEX4protein BEX4