title: [Role of chloride channels in gambogic acid-induced apoptosis of poorly differentiated nasopharyngeal carcinoma cells].
abstract: OBJECTIVE
  To investigate the role of chloride channels in the apoptosis of poorly differentiated nasopharyngeal carcinoma CNE-2Z cells induced by gambogic acid (GA).
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Physiology, Medical College, Jinan University, Guangzhou 510632, China. E-mail: tbzq@jnu.edu.cn.
authors.forename: Zhi-quan
authors.initials: ZQ
authors.lastname: Bai
authors.forename: Hua-rong
authors.initials: HR
authors.lastname: Li
authors.forename: Hai-feng
authors.initials: HF
authors.lastname: Zhang
authors.forename: Shan-wen
authors.initials: SW
authors.lastname: Liu
authors.forename: Lin-yan
authors.initials: LY
authors.lastname: Zhu
authors.forename: Wen-cai
authors.initials: WC
authors.lastname: Ye
authors.forename: Li-xin
authors.initials: LX
authors.lastname: Chen
authors.forename: Li-wei
authors.initials: LW
authors.lastname: Wang
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D018118:Chloride Channels / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D018408:Patch-Clamp Techniques; D044004:Xanthones / Q000494:pharmacology*
chemical_list: D018118:Chloride Channels; D044004:Xanthones; C052659:gambogic acid