title: Prognostic impact of MiR-155 in non-small cell lung cancer evaluated by in situ hybridization.
abstract: BACKGROUND
  In recent years, microRNAs (miRNAs) have been found to play an essential role in tumor development. In lung tumorigenesis, targets and pathways of miRNAs are being revealed, and further translational research in this field is warranted. MiR-155 is one of the miRNAs most consistently involved in various neoplastic diseases. We aimed to investigate the prognostic impact of the multifunctional miR-155 in non-small cell lung cancer (NSCLC) patients.
  
  
  METHODS
  Tumor tissue samples from 335 resected stage I to IIIA NSCLC patients were obtained and tissue microarrays (TMAs) were constructed with four cores from each tumor specimen. In situ hybridization (ISH) was used to evaluate the expression of miR-155.
  
  
  RESULTS
  There were 191 squamous cell carcinomas (SCCs), 95 adenocarcinomas (ACs), 31 large cell carcinomas and 18 bronchioalveolar carcinomas. MiR-155 expression did not have a significant prognostic impact in the total cohort (P = 0.43). In ACs, high miR-155 expression tended to a significant negative prognostic effect on survival in univariate analysis (P = 0.086) and was an independent prognostic factor in multivariate analysis (HR 1.87, CI 95% 1.01 - 3.48, P = 0.047). In SCC patients with lymph node metastasis, however, miR-155 had a positive prognostic impact on survival in univariate (P = 0.034) as well as in multivariate (HR 0.45, CI 95% 0.21-0.96, P = 0.039) analysis.
  
  
  CONCLUSIONS
  The prognostic impact of miR-155 depends on histological subtype and nodal status in NSCLC.
authors.affiliation: Department of Oncology, University Hospital of North Norway, Tromso, Norway. tom.donnem@uit.no
authors.forename: Tom
authors.initials: T
authors.lastname: Donnem
authors.forename: Katrine
authors.initials: K
authors.lastname: Eklo
authors.forename: Thomas
authors.initials: T
authors.lastname: Berg
authors.forename: Sveinung W
authors.initials: SW
authors.lastname: Sorbye
authors.forename: Kenneth
authors.initials: K
authors.lastname: Lonvik
authors.forename: Samer
authors.initials: S
authors.lastname: Al-Saad
authors.forename: Khalid
authors.initials: K
authors.lastname: Al-Shibli
authors.forename: Sigve
authors.initials: S
authors.lastname: Andersen
authors.forename: Helge
authors.initials: H
authors.lastname: Stenvold
authors.forename: Roy M
authors.initials: RM
authors.lastname: Bremnes
authors.forename: Lill-Tove
authors.initials: LT
authors.lastname: Busund
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017403:In Situ Hybridization; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000502:physiology*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016019:Survival Analysis
chemical_list: C524942:MIRN155 microRNA, human; D035683:MicroRNAs