title: Association between COX-2 rs 6681231 genotype and interleukin-6 in periodontal connective tissue. A pilot study.
abstract: OBJECTIVE
  The aim of this pilot study was to investigate associations between IL-6 and COX-2 expression in gingival biopsies and both clinical diagnosis and genotypes in the IL-6 and COX-2 genes.
  
  
  METHODS
  A case-control study included 41 gingival biopsies obtained from Caucasian patients grouped according to clinical diagnosis of gingival health (n = 10), gingivitis (n = 15) or chronic periodontitis (n = 16). Immunohistochemistry analyses were performed to determine COX-2 expression in lamina propria, IL-6 expression in lamina propria and gingival epithelium and level of inflammatory cell infiltrate. Individual DNA was extracted and genotyped by real-time PCR for IL6 SNPs rs 2069827 and rs 2069825 and for COX-2 rs 6681231.
  
  
  RESULTS
  The percentage of cellular COX-2 expression was associated with the extent of periodontal disease (Arbes index p = 0.026) and inflammatory infiltrate (p<0.0001). No association was observed between IL6 haplotypes and cells positive to IL-6 or COX-2 in gingival tissues. The COX-2 rs 6681231 was associated with cells positive to IL-6 in the connective tissue (p = 0.032).
  
  
  CONCLUSIONS
  COX-2 expression in gingival tissues may be a marker of periodontal disease severity. COX-2 rs 6681231 may be associated with IL-6 local production in gingival tissues.
authors.affiliation: Department of Periodontics, School of Dentistry, University of Granada, Granada, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Mesa
authors.affiliation: Departments of Pathology, School of Medicine and Biopathology and Medicine Regenerative Institute (IBIMER), University of Granada, Granada, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: O'Valle
authors.affiliation: Department of Internal Medicine, University of Palermo, Palermo, Italy ; Euro-Mediterranean Institute of Science and Technology, Palermo, Italy.
authors.forename: Manfredi
authors.initials: M
authors.lastname: Rizzo
authors.affiliation: Department of Experimental Medicine and Clinical Neuroscience, Section of Human Anatomy, University of Palermo, Palermo, Italy ; Euro-Mediterranean Institute of Science and Technology, Palermo, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Cappello
authors.affiliation: Periodontology Unit and Department of Clinical Research, University College London (UCL) Eastman Dental Institute and Hospital, London, United Kingdom.
authors.forename: Nikos
authors.initials: N
authors.lastname: Donos
authors.affiliation: Periodontology Unit and Department of Clinical Research, University College London (UCL) Eastman Dental Institute and Hospital, London, United Kingdom.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Parkar
authors.affiliation: Periodontology Unit and Department of Clinical Research, University College London (UCL) Eastman Dental Institute and Hospital, London, United Kingdom.
authors.forename: Navidah
authors.initials: N
authors.lastname: Chaudhary
authors.affiliation: Department of Experimental Medicine and Clinical Neuroscience, Section of Human Anatomy, University of Palermo, Palermo, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Carini
authors.affiliation: Andalusian Service of Public Health, Granada, Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Muñoz
authors.affiliation: Periodontology Unit and Department of Clinical Research, University College London (UCL) Eastman Dental Institute and Hospital, London, United Kingdom.
authors.forename: Luigi
authors.initials: L
authors.lastname: Nibali
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D055113:Chronic Periodontitis / Q000235:genetics* / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D005881:Gingiva / Q000378:metabolism* / Q000473:pathology; D005891:Gingivitis / Q000235:genetics* / Q000473:pathology; D006239:Haplotypes; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D010865:Pilot Projects; D020641:Polymorphism, Single Nucleotide
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human