title: [Down-regulation of Notch1 by small interfering RNA enhances chemosensitivity to gemcitabine in pancreatic cancer cells through activating apoptosis activity].
abstract: To investigate the effect of down-regulation of Notch1 by Notch1 small interfering RNA (siRNA) on chemosensitivity to gemcitabine in pancreatic cancer cells and its mechanism.
  
  
  
  Notch1 siRNA was transfected to pancreatic cancer cell lines AsPC-1, BxPC-3, MIAPaCa-2 and Panc-1. The transfected pancreatic cancer cells were treated with 10 μmol/L gemcitabine in vitro. The relative quantity of Notch1 mRNA of pancreatic cancer cells was detected by real-time PCR. The inhibition rates of gemcitabine-treated cells were evaluated by CCK-8 method. The expression of Bax protein was examined by Western blot, and the caspase 3 activity was detected by CaspACETM assay system kit.
  
  
  
  The relative quantity of Notch1 mRNA was the highest in BxPC-3 cell line and the lowest in Panc-1 cells. The inhibition rates of gemcitabine treated-cells were significantly higher in Notch1 siRNA transfection groups than in corresponding siRNA control groups (AsPC-1: 67.5±6.7 vs 47.5±6.8; BxPC-3: 90.5±4.4 vs 70.2±4.2; MIAPaCa-2: 80.9±5.7 vs 58.1±6.0; Ps<0.05), with the overexpression of protein Bax. The activity of caspase 3 was also significantly increased in Notch1 siRNA transfection groups compared with corresponding siRNA control groups (AsPC-1: 28.90±2.70 vs 12.82±3.44; BxPC-3: 59.87±6.77 vs 27.27±11.88; MIAPaCa-2: 29.34±4.06 vs 14.59±4.25; P<0.05).
  
  
  
  Inhibition of Notch signaling pathway by Notch1 siRNA can enhance chemosensitivity to gemcitabine in pancreatic cancer cells through activating apoptosis activity．
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Du
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Yi-han
authors.initials: YH
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Zi-qiang
authors.initials: ZQ
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Jian-kun
authors.initials: JK
authors.lastname: Hu
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Zhi-Xin
authors.initials: ZX
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery， West China Hospital， Sichuan University， Chengdu 610041， China.
authors.forename: Zong-guang
authors.initials: ZG
authors.lastname: Zhou
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D015536:Down-Regulation; D006801:Humans; D010190:Pancreatic Neoplasms / Q000473:pathology*; D034741:RNA, Small Interfering / Q000235:genetics*; D051881:Receptor, Notch1 / Q000235:genetics*; D015398:Signal Transduction; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D000093542:Gemcitabine
chemical_list: C494826:BAX protein, human; C497761:NOTCH1 protein, human; D034741:RNA, Small Interfering; D051881:Receptor, Notch1; D051028:bcl-2-Associated X Protein; D003841:Deoxycytidine; C505407:CASP3 protein, human; D053148:Caspase 3; D000093542:Gemcitabine