title: Tetraethylammonium inhibits glioma cells via increasing production of intracellular reactive oxygen species.
abstract: BACKGROUND
  Potassium channel blockers have been shown to possess antitumor properties, but the role of apoptosis remains to be clarified. In this study, we investigated the antiproliferative effect of tetraethylammonium (TEA), a nonspecific potassium channel blocker, in rat C6 and 9L glioma cells.
  
  
  METHODS
  Cytotoxicity was evaluated by MTT assay. Apoptosis was detected by TUNEL and annexin V-FITC/propidium iodide assays. Protein levels were determined by Western blot analysis. Intracellular reactive oxygen species (ROS) levels were assessed flow cytometrically.
  
  
  RESULTS
  TEA (2-60 mM) significantly inhibited the proliferation of C6 and 9L glioma cells. In addition, increased cell apoptosis was confirmed after treatment with 40 mM TEA. Apoptosis was associated with a dramatic increase in ROS levels and altered Bcl-2/Bax protein balance.
  
  
  CONCLUSIONS
  TEA can inhibit proliferation and induce apoptosis in both cell lines; therefore, it might be associated with the increase in intracellular ROS production.
authors.affiliation: Neurosurgery Department, First Affiliated Hospital of Harbin Medical University, Harbin, China.
authors.forename: K B
authors.initials: KB
authors.lastname: Yang
authors.forename: S G
authors.initials: SG
authors.lastname: Zhao
authors.forename: Y H
authors.initials: YH
authors.lastname: Liu
authors.forename: E X
authors.initials: EX
authors.lastname: Hu
authors.forename: B X
authors.initials: BX
authors.lastname: Liu
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017209:Apoptosis; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D005910:Glioma / Q000188:drug therapy* / Q000378:metabolism; D026902:Potassium Channel Blockers / Q000627:therapeutic use*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D019789:Tetraethylammonium / Q000627:therapeutic use*
chemical_list: D000970:Antineoplastic Agents; D026902:Potassium Channel Blockers; D017382:Reactive Oxygen Species; D019789:Tetraethylammonium