title: Construction of survivin siRNA expression vector and its regulation on cell cycle and proliferation in MCF-7 cells.
abstract: OBJECTIVE
  Survivin is specifically overexpressed in tumor tissues. Many reports have shown that the abrogation of its functions is useful for tumor therapy. RNA interference is a new technique that proved to be effective for suppressing gene expression. The aim of this study was to construct a siRNA expression plasmid against gene survivin, and then to assess its functions on breast cancer cells MCF-7.
  
  
  METHODS
  A survivin siRNA plasmid was constructed using a mU6pro vector contained U6 promotor, the expression change of survivin was examined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis after the plasmid had been transfected into MCF-7 cells, and the effect of the plasmid on the cell cycle and cell proliferation was analyzed by flow cytometry and MTT method,respectively.
  
  
  RESULTS
  Survivin siRNA plasmid knocked down survivin expression in MCF-7 cells obviously, arrested the cell cycle in G1 phase, inhibited the cell proliferation significantly, and promoted cell apoptosis in a tendency.
  
  
  CONCLUSIONS
  Survivin expression was knocked down at mRNA and protein levels by RNAi.
authors.affiliation: Department of Biochemistry, Zhongshan Medical College, Sun Yat-sen University, Guangzhou, Guangdong, 510089, P.R.China.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Li
authors.forename: Nian-Ci
authors.initials: NC
authors.lastname: Liang
authors.forename: Chao-Quan
authors.initials: CQ
authors.lastname: Luo
mesh_terms: D017209:Apoptosis; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002453:Cell Cycle; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015536:Down-Regulation; D005260:Female; D016193:G1 Phase; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis* / Q000235:genetics; D009363:Neoplasm Proteins; D010957:Plasmids; D034741:RNA, Small Interfering / Q000096:biosynthesis* / Q000235:genetics; D000077022:Survivin; D014162:Transfection
chemical_list: C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D034741:RNA, Small Interfering; D000077022:Survivin