title: Paris chinensis dioscin induces G2/M cell cycle arrest and apoptosis in human gastric cancer SGC-7901 cells.
abstract: OBJECTIVE
  To investigate the anti-tumor effects of Paris chinensis dioscin (PCD) and mechanisms regarding cell cycle regulation and apoptosis in human gastric cancer SGC-7901 cells.
  
  
  METHODS
  Cell viability was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. Cell apoptosis was evaluated by flow cytometry and laser scanning confocal microscope (LSCM) using Annexin-V/propidium iodide (PI) staining, and the cell cycle was evaluated using PI staining with flow cytometry. Intracellular calcium ions were detected under fluorescence microscope. The expression of cell cycle and apoptosis-related proteins cyclin B1, CDK1, cytochrome C and caspase-3 was measured by immunohistochemical staining.
  
  
  RESULTS
  PCD had an anti-proliferation effect on human gastric cancer SGC-7901 cells in a dose- and time-dependent manner. After treatment of SGC-7901 cells with PCD, apoptosis appeared in SGC-7901 cells. Morphological changes typical of apoptosis were also observed with LSCM by Annexin V/PI staining, and the cell number of the G0/G1 phase was decreased, while the number of cells in the G2/M phase was increased. Cell cycle-related proteins, such as cyclin B1 and CDK1, were all down-regulated, but caspase-3 and cytochrome C were up-regulated. Moreover, intracellular calcium accumulation occurred in PCD-treated cells.
  
  
  CONCLUSIONS
  G2/M phase arrest and apoptosis induced by PCD are associated with the inhibition of CDK-activating kinase activity and the activation of Ca(2+)-related mitochondrion pathway in SGC-7901 cells.
authors: Department of Pathology and Pathophysiology, Taishan Medical University, Taian, Shandong Province, China.
authors: Lin-Lin
authors: LL
authors: Gao
authors: Fu-Rong
authors: FR
authors: Li
authors: Peng
authors: P
authors: Jiao
authors: Ming-Feng
authors: MF
authors: Yang
authors: Xiao-Jun
authors: XJ
authors: Zhou
authors: Yan-Hong
authors: YH
authors: Si
authors: Wen-Jian
authors: WJ
authors: Jiang
authors: Ting-Ting
authors: TT
authors: Zheng
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004144:Diosgenin / Q000031:analogs & derivatives* / Q000494:pharmacology; D016195:G2 Phase / Q000187:drug effects*; D006801:Humans; D019668:Liliaceae / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology; D013274:Stomach Neoplasms / Q000378:metabolism*
chemical_list: D010936:Plant Extracts; C019357:dioscin; D004144:Diosgenin; D002118:Calcium