Role of chloride channels in gambogic acid-induced apoptosis of poorly differentiated nasopharyngeal carcinoma cells / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the role of chloride channels in the apoptosis of poorly differentiated nasopharyngeal carcinoma CNE-2Z cells induced by gambogic acid (GA).</p><p><b>METHODS</b>MTT assay was applied to detect the proliferation of CNE-2Z cells after GA treatment, and the cell apoptosis was detected by Hoechst 33342 staining. Whole-cell patch clamp technique was employed to record GA-activated Cl(-) currents in the cells.</p><p><b>RESULTS</b>GA inhibited the cell proliferation in a time- and concentration-dependent manner with an IC(50) of 3.1 µmol/L for a 48-h treatment. The apoptosis-inducing effect of 8 µmol/L GA was attenuated by the chloride channel blocker NPPB (100 µmol/L) and tamoxifen (20 µmol/L). GA induced an outward-rectified Cl(-) current in the cells, which was significantly inhibited by NPPB.</p><p><b>CONCLUSION</b>GA suppresses cell proliferation and induces apoptosis by activating Cl(-) channels in CNE-2Z cells, suggesting the important role of Cl(-) channels in GA-induced apoptosis.</p>