title: Squamous cell carcinoma of the oral tongue in young non-smokers is genomically similar to tumors in older smokers.
abstract: OBJECTIVE
  Epidemiologic studies have identified an increasing incidence of squamous cell carcinoma of the oral tongue (SCCOT) in younger patients.
  
  
  METHODS
  DNA isolated from tongue tumors of young (<45 years, non-smokers) and old (>45 years) patients at was subjected to whole-exome sequencing and copy-number analysis. These data were compared with data from similar patients in the TCGA (The Cancer Genome Atlas) project.
  
  
  RESULTS
  In this study, we found that gene-specific mutation and copy-number alteration frequencies were similar between young and old patients with SCCOT in two independent cohorts. Likewise, the types of base changes observed in the young cohort were similar to those in the old cohort even though they differed in smoking history. TCGA data also demonstrate that the genomic effects of smoking are tumor site-specific, and we find that smoking has only a minor impact on the types of mutations observed in SCCOT.
  
  
  CONCLUSIONS
  Overall, tumors from young patients with SCCOT appear genomically similar to those of older patients with SCCOT, and the cause for the increasing incidence of young SCCOT remains unknown. These data indicate that the functional impact of smoking on carcinogenesis in SCCOT is still poorly understood.
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Curtis R
authors.initials: CR
authors.lastname: Pickering
authors.affiliation: Bioinformatics and Computational Biology.
authors.forename: Jiexin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: David M
authors.initials: DM
authors.lastname: Neskey
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Mei
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Samar A
authors.initials: SA
authors.lastname: Jasser
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Jiping
authors.initials: J
authors.lastname: Wang
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Ward
authors.affiliation: Radiation Oncology.
authors.forename: C Jillian
authors.initials: CJ
authors.lastname: Tsai
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Ortega Alves
authors.affiliation: Pathology, and.
authors.forename: Jane H
authors.initials: JH
authors.lastname: Zhou
authors.affiliation: Human Genome Sequencing Center; and.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Drummond
authors.affiliation: Pathology, and.
authors.forename: Adel K
authors.initials: AK
authors.lastname: El-Naggar
authors.affiliation: Human Genome Sequencing Center; and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas.
authors.forename: Richard
authors.initials: R
authors.lastname: Gibbs
authors.affiliation: Bioinformatics and Computational Biology, Systems Biology, The University of Texas MD Anderson Cancer Center.
authors.forename: John N
authors.initials: JN
authors.lastname: Weinstein
authors.affiliation: Human Genome Sequencing Center; and.
authors.forename: David A
authors.initials: DA
authors.lastname: Wheeler
authors.affiliation: Bioinformatics and Computational Biology.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery.
authors.forename: Mitchell J
authors.initials: MJ
authors.lastname: Frederick
authors.affiliation: Authors' Affiliations: Departments of Head and Neck Surgery, jmyers@mdanderson.org.
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Myers
mesh_terms: D000328:Adult; D000367:Age Factors; D002294:Carcinoma, Squamous Cell / Q000235:genetics; D056915:DNA Copy Number Variations; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011379:Prognosis; D012907:Smoking / Q000009:adverse effects*; D014062:Tongue Neoplasms / Q000235:genetics*