title: [Cell cycle arrest and apoptosis induced by tubeimoside in HeLa cell].
abstract: OBJECTIVE
  Tubeimoside, which is composed of tubeimoside I (79%) and II (21%), was isolated from the tubers of Bolbostemma paniculatum (Maxim) Franquet (Cucurbitaceae), a traditional Chinese medicine, "Tu-Bei-Mu". This study was designed to investigate the anti-tumor mechanism of tubeimoside.
  
  
  METHODS
  Growth inhibition was measured by MTT assay. Induction of cell cycle arrest and apoptosis was determined by flow cytometry, fluorescence and electron microscopy, and gel electrophoresis of fragmented DNA.
  
  
  RESULTS
  Tubeimoside display strong growth inhibitory effect in a dose- and time-dependant manner against HeLa cells with estimated IC50 values of 20.0, 18.8, and 8.8 mumol/L after 24, 48, and 72 h of treatment with tubeimoside. The flow cytometry profiles revealed that treatment with tubeimoside (5 h; 15, 30, 35 mumol/L) led to a dose-dependant shift from 9.80% up to 21.90%, and 27.00% in percentage of cells with a G2/M-like DNA content. On the other hand, treatment with tubeimoside (12 h, 15, 30, 35 mumol/L) led to a time-dependant shift from 8.20% up to 21.40%, 31.15%, and 34.55%, respectively. Exposure of HeLa cells to 40 mumol/L of tubeimoside induced nuclear shrinkage, chromation condensation and margination against nuclear envelope, subdiploid peak, and DNA fragmentation, characteristic as seen in apoptotic cells.
  
  
  CONCLUSIONS
  Induction of cell cycle arrest and apoptosis may play an important role in the anti-tumor effect of tubeimoside.
authors.affiliation: Guangdong Provincial Key Laboratory of Marine Pharmacy, Zhanjiang Ocean University, Zhangjiang 524025, P. R. China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yang
authors.forename: Ting-xi
authors.initials: TX
authors.lastname: Yu
authors.forename: Run-di
authors.initials: RD
authors.lastname: Ma
authors.forename: Li-jian
authors.initials: LJ
authors.lastname: Yu
authors.forename: Wei-ming
authors.initials: WM
authors.lastname: Su
authors.forename: Hai-yan
authors.initials: HY
authors.lastname: Shao
authors.forename: Ming-neng
authors.initials: MN
authors.lastname: Liao
authors.forename: Lai-zhen
authors.initials: LZ
authors.lastname: Huang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D002453:Cell Cycle / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D012503:Saponins / Q000494:pharmacology*; D014315:Triterpenes / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D004365:Drugs, Chinese Herbal; D012503:Saponins; D014315:Triterpenes; C051084:tubeimoside I