title: MicroRNA-137 promoter methylation is associated with poorer overall survival in patients with squamous cell carcinoma of the head and neck.
abstract: BACKGROUND
  The overall 5-year survival rate of approximately 60% for head and neck cancer patients has remained essentially unchanged over the past 30 years. MicroRNA-137 (miR-137) plays an essential role in cell-cycle control at the G1/S-phase checkpoint. However, the aberrant miR-137 promoter methylation observed in squamous cell carcinoma of the head and neck (SCCHN) suggests a tumor-specific molecular defect that may contribute to disease progression.
  
  
  METHODS
  The goal of this study was to assess, in formalin-fixed, paraffin-embedded tumor tissue, the association between miR-137 promoter methylation and survival (both overall and disease free) and with prognostic factors including stage, tumor size, lymph node positivity, tumor grade, and surgical tumor margin positivity.
  
  
  RESULTS
  The promoter methylation status of miR-137 was ascertained by methylation-specific polymerase chain reaction and detected in 11 of 67 SCCHN patients (16.4%), with no significant differences according to site (oral cavity, pharynx, larynx). Methylation of the miR-137 promoter was significantly associated with overall survival (hazard ratio, 3.68; 95% confidence interval, 1.01-13.38) but not with disease-free survival or any of the prognostic factors evaluated.
  
  
  CONCLUSIONS
  The results of this study indicate that miR-137 is methylated in tumor tissue from pharyngeal and laryngeal squamous cancers, in addition to oral squamous cell carcinoma, and that miR-137 promoter methylation has potential utility as a prognostic marker for SCCHN.
authors.affiliation: University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, Pennsylvania 15213-1863, USA.
authors.forename: Scott M
authors.initials: SM
authors.lastname: Langevin
authors.forename: Roslyn A
authors.initials: RA
authors.lastname: Stone
authors.forename: Clareann H
authors.initials: CH
authors.lastname: Bunker
authors.forename: Maureen A
authors.initials: MA
authors.lastname: Lyons-Weiler
authors.forename: William A
authors.initials: WA
authors.lastname: LaFramboise
authors.forename: Lori
authors.initials: L
authors.lastname: Kelly
authors.forename: Raja R
authors.initials: RR
authors.lastname: Seethala
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Grandis
authors.forename: Robert W
authors.initials: RW
authors.lastname: Sobol
authors.forename: Emanuela
authors.initials: E
authors.lastname: Taioli
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000401:mortality; D019175:DNA Methylation; D018572:Disease-Free Survival; D005260:Female; D006258:Head and Neck Neoplasms / Q000235:genetics* / Q000401:mortality; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000032:analysis*; D008875:Middle Aged; D011379:Prognosis; D011401:Promoter Regions, Genetic
chemical_list: C545567:MIRN137 microRNA, human; D035683:MicroRNAs