title: [Harringtonine induces apoptosis in NB4 cells through down-regulation of Mcl-1].
abstract: To investigate the growth inhibition effect, cytotoxicity and apoptotic induction of harringtonine (HT) in human acute promyelocytic leukemia (APL) NB4 cells,and the related mechanism.
  
  
  
  NB4 cells were treated with HT. Total cell numbers were counted by hemocytometer, and cell viabilities were determined by trypan blue exclusion. Apoptotic cells were determined by fluorescence microscopy and FACS after staining with AO and EB or PI, respectively. The cleavage of PARP and the activation of Bax and the expression of anti-apoptotic proteins were determined by Western Blot. siRNA was used to silence the expression of target genes. Primary cells were isolated following Ficoll-Hypaque density gradient centrifugation method.
  
  
  
  HT inhibited cell growth and induced apoptosis of NB4 cells in a dose- and time-dependent manner. Apoptosis induced by HT was correlated with the down-regulation of Mcl-1 and the cleavage of PARP, while HT did not affect the protein level of Bax and Bak or change the protein level of Bcl-2. The silence of Bcl-XL sensitized HT-induced apoptosis in NB4 cells.Apoptosis induced by HT in primarily cultured APL cells was also correlated with the down-regulation of Mcl-1.
  
  
  
  HT inhibits cell growth and induces apoptosis in NB4 cells and primarily cultured APL cells, which may be associated with down-regulation of Mcl-1.
authors.affiliation: Women's Hospital of Zhejiang University School of Medicine, Hangzhou 310006, China.
authors.forename: Chunxiao
authors.initials: C
authors.lastname: Wu
authors.forename: Hongqiang
authors.initials: H
authors.lastname: Shen
authors.forename: Dajing
authors.initials: D
authors.lastname: Xia
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D018797:Cell Cycle Proteins; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins; D006248:Harringtonines / Q000494:pharmacology*; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000378:metabolism / Q000473:pathology*; D011506:Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: C494772:BAK1 protein, human; C494826:BAX protein, human; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D006248:Harringtonines; C100852:MLF1 protein, human; D011506:Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051028:bcl-2-Associated X Protein