title: Phenethyl isothiocyanate induces calcium mobilization and mitochondrial cell death pathway in cholangiocarcinoma KKU-M214 cells.
abstract: BACKGROUND
  Phenethyl isothiocyanate (PEITC) is a cancer chemopreventive agent from cruciferous vegetables. Cholangiocarcinoma (CCA) is a chemo-resistant cancer with very poor prognosis. We evaluated the effects of PEITC on induction of apoptotic cell death in relation to cellular glutathione (GSH) and mitochondrial function of a CCA cell line, KKU-M214.
  
  
  METHODS
  Cytotoxic effects of PEITC on a CCA cell line, KKU-M214, and a reference cell line, Chang cells were evaluated. To delineate mechanisms of cell death, the following parameters were measured; GSH and superoxide levels as the oxidative status parameters, apoptosis related proteins levels using Western blotting. Cellular free calcium level and mitochondrial transmembrane potential were also measured.
  
  
  RESULTS
  PEITC induced apoptotic cell death of both KKU-M214 and Chang cells. After PEITC treatment, both cells showed decrease of Bcl-xl and increase of Bax levels. While KKU-M214 cells released AIF, Chang cells released cytochrome c, with subsequent activation of caspase 3 and 9, upon PEITC treatment. PEITC induced superoxide formation in both cells, although it seemed not play a role in cell death. PEITC caused GSH redox stress in different ways in two cell types, because N-acetylcysteine (NAC) prevented redox stress in Chang but not in KKU-M214 cells. The loss of mitochondrial transmembrane potential was induced by PEITC concurrent with GSH stress, but was not a primary cause of cell death. The rapid increase of free calcium level in cytosol was associated with cell death in both cell lines. These events were prevented by NAC in Chang cells, but not in KKU-M214 cells.
  
  
  CONCLUSIONS
  PEITC induced cell death KKU-M214 cells and Chang cells via increase of cellular calcium mobilization and activation of mitochondrial cell death pathway. The effects of PEITC on the redox stress was mediated via different ways in CCA and Chang cells because NAC could prevent redox stress in Chang cells, but not in KKU-M214 cells. The multiple effects of PEITC may be useful for the development of novel chemotherapy for CCA.
authors.forename: Ornanong
authors.initials: O
authors.lastname: Tusskorn
authors.forename: Laddawan
authors.initials: L
authors.lastname: Senggunprai
authors.forename: Auemduan
authors.initials: A
authors.lastname: Prawan
authors.forename: Upa
authors.initials: U
authors.lastname: Kukongviriyapan
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Mitraparb Road, Khon Kaen 40002, Thailand. veerapol@kku.ac.th.
authors.forename: Veerapol
authors.initials: V
authors.lastname: Kukongviriyapan
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D018281:Cholangiocarcinoma; D004354:Drug Screening Assays, Antitumor; D004789:Enzyme Activation; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D020128:Inhibitory Concentration 50; D017879:Isothiocyanates / Q000494:pharmacology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; D051017:Apoptosis Regulatory Proteins; D017879:Isothiocyanates; D017382:Reactive Oxygen Species; C058305:phenethyl isothiocyanate; D020169:Caspases; D005978:Glutathione; D000111:Acetylcysteine