title: [Anti-tumor effect of ethanol extracts from Thymus quinquecostatus Celak on human leukemia cell line].
abstract: OBJECTIVE
  To screen the anti-tumor fraction of ethanol extracts from Thymus quinquecostatus Celak and investigate its anti-tumor effect on human leukemia cell line.
  
  
  METHODS
  Ethyl acetate, n-butanol and acetone fractions were separated from the ethanol extracts of wild Thymus quinquecostatus Celak. Growth inhibiting effects of these extracts on human leukemia cell lines K562 and HL-60 were determined by live cell counting and cell growth curve analysis. The possible anti-tumor mechanism was studied by morphological analysis with norcantharidin as a positive control.
  
  
  RESULTS
  Ethyl acetate fraction could significantly inhibit the proliferations of K562 and HL-60 cells, and the inhibiting effect depended on the concentration of ethyl acetate fraction. Ethyl acetate fraction could induce apoptosis of K562 and HL-60 cells. The n-butanol and acetone fractions had no significant inhibiting effect on K562 and HL-60 cells.
  
  
  CONCLUSIONS
  Ethyl acetate fraction is the major anti-tumor fraction in ethanol extracts from Thymus quinquecostatus Celak.
authors.affiliation: School of Chinese Materia Medica, Beijing University of Traditional Chinese Medicine, Beijing 100102, China. sunzxcn@sohu.com
authors.forename: Zhen-Xiao
authors.initials: ZX
authors.lastname: Sun
authors.forename: Ying-Hui
authors.initials: YH
authors.lastname: Zhang
authors.forename: Shuang
authors.initials: S
authors.lastname: Cheng
authors.forename: Qing-Wen
authors.initials: QW
authors.lastname: Ma
authors.forename: Shan-Li
authors.initials: SL
authors.lastname: Guo
authors.forename: Jin-Bao
authors.initials: JB
authors.lastname: Zhang
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D018922:HL-60 Cells; D006801:Humans; D020014:K562 Cells; D046930:Thymus Plant / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal