title: The prognostic importance of miR-21 in stage II colon cancer: a population-based study.
abstract: BACKGROUND
  Despite several years of research and attempts to develop prognostic models a considerable fraction of stage II colon cancer patients will experience relapse within few years from their operation. The aim of the present study was to investigate the prognostic importance of miRNA-21 (miR-21), quantified by in situ hybridisation, in a unique, large population-based cohort.
  
  
  METHODS
  The study included 764 patients diagnosed with stage II colon cancer in Denmark in the year 2003. One section from a representative paraffin-embedded tumour tissue specimen from each patient was processed for analysis of miR-21 and quantitatively assessed by image analysis.
  
  
  RESULTS
  The miR-21 signal was predominantly observed in fibroblast-like cells located in the stromal compartment of the tumours. We found that patients expressing high levels of miR-21 had significantly inferior recurrence-free cancer-specific survival (RF-CSS): HR=1.26; 95% CI: 1.15-1.60; P<0.001. In Cox regression analysis, a high level of miR-21 retained its prognostic importance and was found to be significantly related to poor RF-CSS: HR=1.41; 95% CI: 1.19-1.67; P<0.001.
  
  
  CONCLUSIONS
  The present study showed that increasing miR-21 expression levels were significantly correlated to decreasing RF-CSS. Further investigations of the clinical importance of miR-21 in the selection of high-risk stage II colon cancer patients are merited.
authors.affiliation: Department of Oncology, Danish Colorectal Cancer Group South, Vejle Hospital, Kabbeltoft 25, Vejle, Denmark. Sanne.Kjaer.Frifeldt@slb.regionsyddanmark.dk
authors.forename: S
authors.initials: S
authors.lastname: Kjaer-Frifeldt
authors.forename: T F
authors.initials: TF
authors.lastname: Hansen
authors.forename: B S
authors.initials: BS
authors.lastname: Nielsen
authors.forename: S
authors.initials: S
authors.lastname: Joergensen
authors.forename: J
authors.initials: J
authors.lastname: Lindebjerg
authors.forename: F B
authors.initials: FB
authors.lastname: Soerensen
authors.forename: R
authors.initials: R
authors.lastname: dePont Christensen
authors.forename: A
authors.initials: A
authors.lastname: Jakobsen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000235:genetics* / Q000473:pathology*; D003718:Denmark; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis
chemical_list: C524940:MIRN21 microRNA, human; D035683:MicroRNAs