title: Expression level of Bmi-1 oncoprotein is associated with progression and prognosis in colon cancer.
abstract: OBJECTIVE
  To investigate the clinicopathologic significance and predictive value of Bmi-1 expression in patients with colon cancer.
  
  
  METHODS
  Bmi-1 expression was assessed by immunohistochemistry, PCR, and western blotting in specimens from 203 patients and by immunohistochemistry in 66 specimens of lymph node metastasis (LNM).
  
  
  RESULTS
  Positive staining of Bmi-1 occurred in 7.9% (16/203), 66.5% (135/203), and 86.4% (57/66) of specimens from normal tissue, colon cancer, and LNM, respectively. Staining was significantly correlated with clinical stage, depth of invasion, nodal involvement, distant metastasis, and Ki67 level. Bmi-1 was upregulated at the transcriptional and translational levels. Patients with Bmi-1-positive localized tumors had a much lower 5-year disease-free survival (relative risk 2.919, P < 0.0001) and overall survival (relative risk 5.056, P < 0.0001). Bmi-1 immunoreactivity emerged as an independent prognostic factor in the multivariate analysis.
  
  
  CONCLUSIONS
  We have shown that expression of Bmi-1 was elevated in colon cancer and might serve as an independent prognostic marker.
authors.affiliation: Department of General Surgery, Shanghai Jiaotong University Affiliated with First People's Hospital, Shanghai, People's Republic of China.
authors.forename: Da-wei
authors.initials: DW
authors.lastname: Li
authors.forename: Hua-mei
authors.initials: HM
authors.lastname: Tang
authors.forename: Jun-wei
authors.initials: JW
authors.lastname: Fan
authors.forename: Dong-wang
authors.initials: DW
authors.lastname: Yan
authors.forename: Chong-zhi
authors.initials: CZ
authors.lastname: Zhou
authors.forename: Shu-xia
authors.initials: SX
authors.lastname: Li
authors.forename: Xiao-liang
authors.initials: XL
authors.lastname: Wang
authors.forename: Zhi-hai
authors.initials: ZH
authors.lastname: Peng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis / Q000235:genetics; D015153:Blotting, Western; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000235:genetics; D063150:Polycomb Repressive Complex 1; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis* / Q000235:genetics; D012008:Recurrence; D012097:Repressor Proteins / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D055815:Young Adult
chemical_list: C069077:BMI1 protein, human; D014408:Biomarkers, Tumor; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D063150:Polycomb Repressive Complex 1