title: Salivary interleukin-6 and -8 in patients with oral cancer and patients with chronic oral inflammatory diseases.
abstract: BACKGROUND
  Previous research has indicated that salivary interleukin (IL)-6 and IL-8 are potential biomarkers for oral squamous cell carcinoma (OSCC). However, their levels have been found to be significantly elevated in patients with chronic periodontitis (CP) or oral lichen planus (OLP). The data also showed wide variations in levels among the different studies, and no standardization procedure was ever performed. Therefore, the objective of this study is to determine whether CP or OLP confounds the use of IL-6 or IL-8 for OSCC detection.
  
  
  METHODS
  Saliva samples were collected from five groups: OSCC before treatment (n = 18); CP (n = 21); disease-active OLP (n = 21); disease-inactive OLP (n = 20); and healthy controls (n = 21). IL-6 and IL-8 concentrations (determined by enzyme-linked immunosorbent assays) were compared, using total salivary protein-standardized levels to validate the data. The Kruskal-Wallis test (α = 0.05) followed by pairwise Mann-Whitney U (post hoc) tests with Bonferroni adjustments (α = 0.00625) were used for statistical analysis.
  
  
  RESULTS
  Salivary IL-6 levels were significantly higher in patients with OSCC than in patients with CP (P <0.001), disease-active OLP (P = 0.001), disease-inactive OLP (P <0.001), and healthy controls (P <0.001). Salivary IL-8 levels were significantly higher in patients with OSCC than in patients with CP (P <0.001), but only marginally significantly higher than in healthy controls (P = 0.014). Statistical results of standardized IL-6 and IL-8 levels were consistent with the non-standardized levels in all pairs except one.
  
  
  CONCLUSIONS
  Salivary IL-6 may be a useful biomarker in the detection of OSCC, unconfounded by CP or OLP.
authors.affiliation: Diagnostic Sciences, Baylor College of Dentistry, Texas A&M University, Dallas, TX.
authors.forename: Yi-Shing
authors.initials: YS
authors.lastname: Lisa Cheng
authors.forename: Lee
authors.initials: L
authors.lastname: Jordan
authors.forename: Lakshmi Mitreyi
authors.initials: LM
authors.lastname: Gorugantula
authors.forename: Emet
authors.initials: E
authors.lastname: Schneiderman
authors.forename: Huey-Shys
authors.initials: HS
authors.lastname: Chen
authors.forename: Terry
authors.initials: T
authors.lastname: Rees
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis; D002294:Carcinoma, Squamous Cell / Q000276:immunology*; D055113:Chronic Periodontitis / Q000145:classification / Q000276:immunology*; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis*; D016209:Interleukin-8 / Q000032:analysis*; D017676:Lichen Planus, Oral / Q000145:classification / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000276:immunology*; D009367:Neoplasm Staging; D012463:Saliva / Q000276:immunology*; D012471:Salivary Proteins and Peptides / Q000032:analysis
chemical_list: D015415:Biomarkers; D014408:Biomarkers, Tumor; C508606:CXCL8 protein, human; C508600:IL6 protein, human; D015850:Interleukin-6; D016209:Interleukin-8; D012471:Salivary Proteins and Peptides
keywords: Chronic periodontitis; interleukin-6; interleukin-8; lichen planus; mouth neoplasms; oral; saliva