title: Anti-proliferation effect of oridonin on HL-60 cells and its mechanism.
abstract: OBJECTIVE
  To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism.
  
  
  METHODS
  HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred.
  
  
  RESULTS
  Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin.
  
  
  CONCLUSIONS
  Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.
authors.affiliation: Laboratory of Forensic and Biological Science, Medical College of Sun Yat-Sen University, Guangzhou 510080.
authors.forename: Jia-Jun
authors.initials: JJ
authors.lastname: Liu
authors.forename: Xin-Yao
authors.initials: XY
authors.lastname: Wu
authors.forename: Hui-Ling
authors.initials: HL
authors.lastname: Lul
authors.forename: Xiang-Lin
authors.initials: XL
authors.lastname: Pan
authors.forename: Jun
authors.initials: J
authors.lastname: Peng
authors.forename: Ren-Wei
authors.initials: RW
authors.lastname: Huang
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D004224:Diterpenes / Q000302:isolation & purification / Q000494:pharmacology*; D045786:Diterpenes, Kaurane; D018922:HL-60 Cells; D006801:Humans; D037602:Isodon / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D019098:Telomerase / Q000378:metabolism*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004224:Diterpenes; D045786:Diterpenes, Kaurane; C011959:oridonin; D019098:Telomerase