title: Cyclo-oxygenase-2 expression in oral squamous cell carcinoma.
abstract: BACKGROUND
  Many evidences showed that cyclooxygenase-2 (COX-2), an enzyme that catalyzes the synthesis of prostaglandins, has an important role in carcinogenesis. It has been observed in experimental models that selective COX-2 inhibitors suppress the formation of tumors including tongue carcinoma. The aim of this study was to investigate the immunohistochemical expression of COX-2 in oral squamous cell carcinoma (OSCC) compared to normal oral mucosa and oral dysplasia.
  
  
  METHODS
  A total of 60 paraffined blocks (20 cases of OSCC, 20 cases of oral epithelial dysplasia and 20 cases of normal oral mucosa were included in this study and immunohistochemical staining was done for COX-2 expression. From each sample, 5 high power fields were assessed to determine the percentage of stained cells and staining intensity. Immunoreactivity was obtained by multiplying the above two cases. Data were analyzed with using the Kruskal-Wallis test ANOVA, Mann-Whitney test and least significant difference and P<0.05 was declared as significant.
  
  
  RESULTS
  High level of COX-2 expression was found in OSCC and dysplasia compared to normal mucosa. Furthermore, a positive correlation was found between COX-2 expression and severity of dysplasia. However, no significant difference between low grade and high grade tumors was found.
  
  
  CONCLUSIONS
  The result of the present study supports from the role of COX-2 in carcinogenesis and progression of premalignant lesion to malignancy.
authors.affiliation: Department of Oral and Maxillofacial Pathology of Dental Materials Research Center, Dental Faculty, Babol University of Medical Sciences, Babol, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Seyedmajidi
authors.forename: Shahryar
authors.initials: S
authors.lastname: Shafaee
authors.forename: Sepideh
authors.initials: S
authors.lastname: Siadati
authors.forename: Monireh
authors.initials: M
authors.lastname: Khorasani
authors.forename: Ali
authors.initials: A
authors.lastname: Bijani
authors.forename: Nafiseh
authors.initials: N
authors.lastname: Ghasemi
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000201:enzymology; D002294:Carcinoma, Squamous Cell / Q000201:enzymology*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000378:metabolism / Q000473:pathology; D009062:Mouth Neoplasms / Q000201:enzymology*; D014062:Tongue Neoplasms / Q000201:enzymology; D055815:Young Adult
chemical_list: D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human