Bestrophin-4 (BEST4)

Bestrophin-4 is a member of the bestrophin family of calcium-activated chloride channels, encoded by the BEST4 gene, predominantly expressed in colon epithelial cells. It mediates the movement of chloride and bicarbonate ions in a calcium-dependent manner and helps regulate ion transport and epithelial cell function. Unlike other bestrophins, BEST4 has distinctive functional properties, including slow activation/deactivation kinetics and specific structural divergence in transmembrane and extra-membrane loop regions. Recent studies indicate BEST4 can suppress colorectal cancer cell proliferation, migration, and epithelial-mesenchymal transition (EMT) through upstream regulation by Hes4 and downregulation of Twist1, and its anti-tumor activity appears partly independent of its channel function. It is considered a molecular target for both ion transport modulation and clinical prognostication in colorectal cancer.

Other names

BEST4Bestrophin-4VMD2L2Vitelliform macular dystrophy 2-like protein 2vitelliform macular dystrophy 2-like 2

Inhibition of chloride channel activity (by DIDS, CaCCinh-A01); Activation of ion transport (by ionomycin, potential small-molecule agonists like PABA, glutamate, GABA)