OCLN and neoplasm: Occludin, which acts with Claudin-1 to form intercellular tight junctions on the cytoplasmic membrane, contributes to tight junction stabilization and optimal barrier function in the epithelium.43 Loss of Occludin led to failure of epithelial cell tight junctions and is associated with invasion and metastasis in GBC, but patients with higher Occludin expression in tumorous tissue survived longer than those with reduced or no Occludin expression.20