title: Galangin induces apoptosis of hepatocellular carcinoma cells via the mitochondrial pathway.
abstract: OBJECTIVE
  To investigate the mechanism by which galangin, a polyphenolic compound derived from medicinal herbs, induces apoptosis of hepatocellular carcinoma (HCC) cells.
  
  
  METHODS
  The 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay was used to measure cell viability. Apoptosis was evaluated by in situ uptake of propidium iodide and Hoechst 33258 and was then detected by fluorescence microscopy. Protein expressions were detected by Western blotting. To confirm the apoptotic pathway mediated by galangin, cells were transfected by bcl-2 gene to overexpress Bcl-2 or siRNA to down-regulate Bcl-2 expression.
  
  
  RESULTS
  Galangin (46.25-370.0 micromol/L) exerted an anti-proliferative effect, induced apoptosis, and decreased mitochondrial membrane potential in a dose and time-dependent manner. Treatment with galangin induced apoptosis by translocating the pro-apoptotic protein Bax to the mitochondria, which released apoptosis-inducing factor and cytochrome c into the cytosol. Overexpression of Bcl-2 attenuated galangin-induced HepG2 cell apoptosis, while decreasing Bcl-2 expression enhanced galangin-induced cell apoptosis.
  
  
  CONCLUSIONS
  Our data suggests that galangin mediates apoptosis through a mitochondrial pathway, and may be a potential chemotherapeutic drug for the treatment of HCC.
authors.affiliation: Institute of Biochemistry and Molecular Biology, Guangdong Medical College, Zhanjiang 524023, Guangdong Province, China. taohaizhang@tom.com
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Luo
authors.forename: Jun
authors.initials: J
authors.lastname: Wu
authors.forename: Liu-Bo
authors.initials: LB
authors.lastname: Lan
authors.forename: Da-Hua
authors.initials: DH
authors.lastname: Fan
authors.forename: Kai-Dan
authors.initials: KD
authors.lastname: Zhu
authors.forename: Xiao-Yi
authors.initials: XY
authors.lastname: Chen
authors.forename: Min
authors.initials: M
authors.lastname: Wen
authors.forename: Hui-Ming
authors.initials: HM
authors.lastname: Liu
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D009153:Mutagens / Q000494:pharmacology* / Q000627:therapeutic use; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
chemical_list: D005419:Flavonoids; D009153:Mutagens; D019253:Proto-Oncogene Proteins c-bcl-2; C037032:galangin