title: siRNA targeting of Cdx2 inhibits growth of human gastric cancer MGC-803 cells.
abstract: OBJECTIVE
  To investigate the effects of small interference RNA (siRNA) targeting of Cdx2 on human gastric cancer MGC-803 cells in vitro and in vivo.
  
  
  METHODS
  The recombinant pSilencer 4.1-Cdx2 siRNA plasmids were constructed and transfected into gastric cancer MGC-803 cells in vitro. The stable transfectants were selected. The effects of Cdx2 siRNA on growth, proliferation, cell cycle, apoptosis, migration and invasiveness of human gastric cancer MGC-803 cells were evaluated and the expression of phosphatase and tensin homolog (PTEN), caspase-9 and caspase-3 was observed in vitro by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting analysis. We also investigated the effect of Cdx2 siRNA on growth of MGC-803 cells in nude mice in vivo.
  
  
  RESULTS
  Cdx2 siRNA led to inhibition of endogenous Cdx2 mRNA and protein expression as determined by RT-PCR and Western blotting analysis. Cdx2 siRNA significantly inhibited cell growth and proliferation, blocked entry into the S-phase of the cell cycle, induced cell apoptosis, and reduced the motility and invasion of MGC-803 cells. Cdx2 siRNA also increased PTEN expression, and activated caspase-9 and caspase-3 in MGC-803 cells in vitro . In addition, siRNA targeting of Cdx2 inhibited the growth of MGC-803 cells and promoted tumor cell apoptosis in vivo in nude mice tumor models.
  
  
  CONCLUSIONS
  Cdx2 was involved in regulating pro-gression of human gastric cancer cells MGC-803. Manipulation of Cdx2 expression may be a potential therapeutic strategy for gastric cancer.
authors.affiliation: Department of Surgery, The First Affiliated Hospital, Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China.
authors.forename: Xiao-Tong
authors.initials: XT
authors.lastname: Wang
authors.forename: Yu-Bo
authors.initials: YB
authors.lastname: Xie
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xiao
mesh_terms: D000818:Animals; D000071616:CDX2 Transcription Factor; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D002453:Cell Cycle; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D018398:Homeodomain Proteins / Q000037:antagonists & inhibitors / Q000502:physiology*; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009361:Neoplasm Invasiveness; D051059:PTEN Phosphohydrolase / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D034741:RNA, Small Interfering / Q000235:genetics*; D013274:Stomach Neoplasms / Q000473:pathology* / Q000628:therapy; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000502:physiology*
chemical_list: D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; C487514:Cdx2 protein, mouse; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014157:Transcription Factors; D051059:PTEN Phosphohydrolase; D053148:Caspase 3; D053453:Caspase 9