title: [Study of gambogenic acid-induced apoptosis of melanoma B16 cells through PI3K/Akt/mTOR signaling pathways].
abstract: OBJECTIVE
  To discuss the mechanism of gambogenic acid (GNA) in inducing the apoptosis of melanoma B16 cells.
  
  
  METHODS
  The inhibitory effect of GNA on the proliferation of B16 cells was measured by the methyl thiazolyl tetrazolium (MTT) assay. The effect of GNA on B16 cells was detected by the Hoechst 33258 staining. The transmission electron microscopy was used to observe the ultra-structure changes of B16 cells. The changes in PI3K, p-PI3K, Akt, p-Akt, p-mTOR, PTEN proteins were detected by the Western blotting to discuss the molecular mechanism of GNA in inducing the apoptosis of B16 cells.
  
  
  RESULTS
  GNA showed a significant inhibitory effect in the growth and proliferation of melanoma B16 cells. The cell viability remarkably decreased with the increase of GNA concentration and the extension of the action time. The results of the Hoechst 33258 staining showed that cells processed with GNA demonstrated apparent apoptotic characteristics. Under the transmission electron microscope, B16 cells, after being treated with GNA, showed obvious morphological changes of apoptosis. The Western blot showed a time-dependent reduction in the p-PI3K and p-Akt protein expressions, with no change in p-PI3K and p-Akt protein expression quantities. The p-mTOR protein expression decreased with the extension of time, where as the PTEN protein expression showed a time-dependent increase.
  
  
  CONCLUSIONS
  GNA could inhibit the proliferation of melanoma B16 cells and induce their apoptosis within certain time and concentration ranges. Its mechanism in inducing the cell apoptosis may be related to PI3K/Akt/mTOR signaling pathways.
authors.forename: Hui
authors.initials: H
authors.lastname: Cheng
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhang
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Su
authors.forename: Qing-Lin
authors.initials: QL
authors.lastname: Li
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008545:Melanoma / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D051379:Mice; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*; D013729:Terpenes / Q000494:pharmacology*; D014966:Xanthenes; D044004:Xanthones / Q000494:pharmacology*
chemical_list: D051059:PTEN Phosphohydrolase; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D058570:TOR Serine-Threonine Kinases; D013729:Terpenes; D014966:Xanthenes; D044004:Xanthones; C045863:neo-gambogic acid