title: [Influence of RNA interference on MSI-2 gene in THP-1 cell and expression of NUMB].
abstract: OBJECTIVE
  To investigate the effect of small interfering RNA（siRNA）for MSI-2 on the growth, apoptosis and NUMB expression of THP-1 cells.
  
  
  METHODS
  Three siRNA for MSI-2 gene was designed and transfected into THP- 1 cells. The cell inhibition, colony formation and apoptosis were determined. The protein expression of NUMB, caspase- 3 and PARP were detected by Western blotting.
  
  
  RESULTS
  After MSI- 2 expression of THP- 1 cells was down- regulated for 24 hours, cell inhibition of siRNA MSI-2 group was（47.89±7.64）%, obviously higher than that of negative control group（P=0.005）. After 9 days, cell colony count of siRNA MSI-2 group was 7.50±1.53, also lower than that of negative control group（35.75±7.46, P<0.001）. In addition, apoptotic rates of siRNA MSI- 2 group at 24 hours ［（15.22±1.52）%］and 48 hours［（33.83±3.96）%］were significantly higher than those of negative control group（P=0.008 and P=0.001, respectively）. Accordingly, activations of caspase-3 and PARP and increased NUMB were observed in siRNA MSI- 2 group.
  
  
  CONCLUSIONS
  siRNA for MSI- 2 gene could increase the expressions of NUMB to inhibit the proliferation and induce apoptosis of THP-1 cells.
authors.affiliation: Departmet of Hematology, The First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China.
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Departmet of Hematology, The First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China.
authors.forename: Qitian
authors.initials: Q
authors.lastname: Mu
authors.affiliation: Departmet of Hematology, The First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China.
authors.forename: Mengxia
authors.initials: M
authors.lastname: Yu
authors.affiliation: Departmet of Hematology, The First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China.
authors.forename: Yungui
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Departmet of Hematology, The First Affiliated Hospital of Zhejiang University, Hangzhou 310003, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Jin
mesh_terms: D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015536:Down-Regulation; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: C438151:MSI2 protein, human; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C113026:NUMB protein, human; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; C505407:CASP3 protein, human; D053148:Caspase 3