title: Knockdown of nucleostemin can inhibit the proliferation of esophageal carcinoma cells in vitro through upregulating p21.
abstract: OBJECTIVE
  Esophageal squamous cell carcinoma is a common digestive tract cancer with poor prognosis. Nucleostemin is a nucleolar protein expressed in stem and cancer cells, involved in the regulation of cell proliferation. p21 plays an important role in negative regulation of the cell-cycle. We investigated the role of nucleostemin through regulating p21 expression in the occurrence and progression of human esophageal carcinoma.
  
  
  METHODS
  The expression of nucleostemin and p21 protein and of nucleostemin was knocked-down by means of RNA interference (RNAi) in Eca109 cells. Then, mRNA and protein expressions of nucleostemin and p21 were determined by reverse transcriptase polymerase chain reaction and Western blotting, respectively. In addition, the effect of nucleostemin RNAi on cell proliferation and cell cycle distribution of Eca109 cells were observed.
  
  
  RESULTS
  Nucleostemin was high expressed, but p21 was low expressed in esophageal carcinoma tissues while increased level of nucleostemin protein was associated with reduced p21. inhibition of nucleostemin resulted in an increased expression of p21 and inhibition of cell proliferation, cause G1/G0 phase cells increased and S-phase cells reduced greatly in Eca109 cells.
  
  
  CONCLUSIONS
  Silence of nucleostemin inhibit cell proliferation through up-regulating p21 expression and nucleostemin may be involved in the pathogenesis of esophageal squamous cell carcinoma.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Sun
authors.forename: Xuyun
authors.initials: X
authors.lastname: Tan
authors.forename: Zimei
authors.initials: Z
authors.lastname: Tang
authors.forename: Guiyong
authors.initials: G
authors.lastname: Peng
authors.forename: Shiming
authors.initials: S
authors.lastname: Yang
authors.forename: Rongquan
authors.initials: R
authors.lastname: Wang
authors.forename: Chunhui
authors.initials: C
authors.lastname: Lan
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Chen
authors.forename: Dianchun
authors.initials: D
authors.lastname: Fang
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000209:etiology / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000502:physiology*; D004938:Esophageal Neoplasms / Q000209:etiology / Q000473:pathology*; D000077277:Esophageal Squamous Cell Carcinoma; D005260:Female; D019204:GTP-Binding Proteins / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000502:physiology*; D016159:Tumor Suppressor Protein p53 / Q000502:physiology; D015854:Up-Regulation
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; C469949:GNL3 protein, human; D009687:Nuclear Proteins; D016159:Tumor Suppressor Protein p53; D019204:GTP-Binding Proteins