title: Downregulation of miRNA-424: a sign of field cancerisation in clinically normal tongue adjacent to squamous cell carcinoma.
abstract: BACKGROUND
  The overall survival for patients with squamous cell carcinoma of the tongue is low and the search for early diagnostic and prognostic markers is thus essential. MicroRNAs have been suggested as potential prognostic and diagnostic candidates in squamous cell carcinoma of head and neck in general.
  
  
  METHODS
  On the basis of the known differences between sub-sites within the oral cavity, we investigated the expression and role of microRNA-424 in squamous cell carcinoma arising in tongue. MicroRNA levels were measured by qRT-PCR in both tissue and plasma samples.
  
  
  RESULTS
  Levels of microRNA-424 were upregulated in tongue squamous cell carcinoma, but not in tumours originating from gingiva or floor of the mouth. Interestingly, microRNA-424 was downregulated in clinically normal tongue tissue next to tumour compared with completely healthy tongue, indicating that microRNA-424 could be a marker of field cancerisation in this tumour type. However, expression of microRNA-424 in a tongue-derived epithelial cell line revealed no significant changes in the expression profile of proteins and genes.
  
  
  CONCLUSIONS
  Our patient data show that microRNA-424 alterations are a marker of field cancerisation specific for tongue tumourigenesis, which also could have a role in development of tongue squamous cell carcinoma.
authors.affiliation: Department of Medical Biosciences/Pathology, Umeå University, Building 6M, 2nd Floor, SE-901 85 Umeå, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Boldrup
authors.affiliation: Division of Medical Sciences, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK.
authors.forename: P J
authors.initials: PJ
authors.lastname: Coates
authors.affiliation: Department of Surgical Sciences/ENT, Uppsala University, SE-751 85 Uppsala, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Laurell
authors.affiliation: Department of Clinical Sciences/ENT, Umeå University, SE-901 85 Umeå, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Wilms
authors.affiliation: Institut de Génétique Moléculaire, Université Paris 7, Hôpital St Louis, 27 rue Juliette Dodu, 75010 Paris, France.
authors.forename: R
authors.initials: R
authors.lastname: Fahraeus
authors.affiliation: Department of Medical Biosciences/Pathology, Umeå University, Building 6M, 2nd Floor, SE-901 85 Umeå, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Nylander
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D063646:Carcinogenesis / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000235:genetics / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood*; D008875:Middle Aged; D011379:Prognosis; D014059:Tongue; D014062:Tongue Neoplasms / Q000097:blood* / Q000235:genetics / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; C554214:MIRN424 microrna, human; D035683:MicroRNAs