Chloride intracellular channel protein 1 (CLIC1)

Chloride intracellular channel protein 1 (CLIC1) is a member of the chloride intracellular channel family. It is encoded by the CLIC1 gene and is structurally homologous to the glutathione S-transferase superfamily[1][2]. CLIC1 exists in both soluble (cytoplasmic/nuclear) and membrane-associated forms, with its insertion into cellular membranes enabling chloride ion conductance[2][8]. CLIC1 plays roles in various fundamental cellular processes, including regulation of membrane potential, cell volume, pH homeostasis, vesicular trafficking, and actin cytoskeleton dynamics[1][3][4][6]. It is expressed in many tissues and is upregulated in various malignancies, such as bladder, breast, liver, and brain cancers, where it is implicated in cell proliferation, tumor aggressiveness, metastasis, and cancer stem cell maintenance[5][7]. Due to its overexpression in tumors and involvement in cancer cell biology, CLIC1 is being investigated both as a potential therapeutic target and as a biomarker, though approved targeted therapies are lacking[5][7][6]. The physiological and pathophysiological mechanisms involving CLIC1 are still under active research, particularly regarding its redox regulation, ion channel activity, and possible protein-protein interactions[2][8].

Other names

CLIC1Nuclear chloride ion channel 27 (NCC27)Chloride channel nuclearChloride intracellular channel 1Chloride channel protein p64

Drugs inhibiting CLIC1 (such as IAA-94): block chloride current, potentially affecting cell cycle, proliferation, and tumor growth [6] Proposed (investigational) targeting mechanism: Inhibition of CLIC1-mediated chloride conductance in cancer cells to suppress tumor cell proliferation and metastasis