title: Bear bile powder (熊胆粉) induces apoptosis of human hepatocellular carcinoma cells via mitochondrion-dependent pathway.
abstract: OBJECTIVE
  To evaluate the effect of Bear Bile Powder(, BBP) on the growth and apoptosis of HepG2 human hepatocellular carcinoma cells, and investigate the possible molecular mechanisms mediating its anti-cancer activity.
  
  
  METHODS
  HepG2 cells were treated with 0.4-1.0 mg/mL of BBP for 24, 48 and 72 h. The viability of HePG2 cells was determined by MTT assay. Cellular morphology was observed via phase-contrast microscopy. Fluorescence-activated cell sorting analysis with Annexin-V/propidium idodide and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazol-carbocyanine iodide (JC-1) staining was performed to determine cell apoptosis and the loss of mitochondrial membrane potential, respectively. Activation of caspase-9 and -3 was evaluated by a colorimetric assay.
  
  
  RESULTS
  The treatment with 0.4-1 mg/mL of BBP for 24, 48, or 72 h respectively reduced cell viability significantly by 7%-60%, 20%-90% or 25%-98%, compared with the untreated control cells (P<0.01). In addition, BBP treatment induced morphological changes in HepG2 cells. Furthermore, after treated with 0, 0.4, 0.6, 0.8 and 1.0 mg/mL of BBP, apoptosis cells (including early and late apoptotic cells) were 18.0%±1.3%, 34.9%±2.2%, 33.9%±2.8%, 37.4%±2.8% and 46.0%±2.5%, respectively (P<0.05); and the percentage of cells with reduced JC-1 red fluorescence were 6.6%±0.8%, 8.5%±0.8%, 13.5%±1.6%, 17.6%±2.3% and 46.7%±3.6%, respectively (P<0.01). Finally, BBP treatment significantly and dose-dependently induced activation of both caspase-9 and caspase-3 in HepG2 cells (P<0.05).
  
  
  CONCLUSIONS
  BBP could inhibit the growth of HepG2 hepatocellular cancer cells through mitochondrion-mediated apoptosis, which may, in part, explain its anti-cancer activity. BBP may be a potential novel therapeutic agent for the treatment of hepatocellular carcinoma.
authors.affiliation: Fujian Academy of Integrative Medicine, Fuzhou, 350108, China.
authors.forename: Jin-yan
authors.initials: JY
authors.lastname: Zhao
authors.forename: Zhi-hong
authors.initials: ZH
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Lin
authors.forename: Xiao-yong
authors.initials: XY
authors.lastname: Zhong
authors.forename: Xu-zheng
authors.initials: XZ
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Peng
authors.forename: Zhen-feng
authors.initials: ZF
authors.lastname: Hong
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001646:Bile; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000473:pathology*; D020169:Caspases / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000494:pharmacology* / Q000627:therapeutic use; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy / Q000473:pathology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D001503:Ursidae
chemical_list: D004365:Drugs, Chinese Herbal; D020169:Caspases