title: Nitric oxide synthase 2 (NOS2) expression in histologically normal margins of oral squamous cell carcinoma.
abstract: The activity of Nitric Oxide Synthase 2 (NOS2) was found in oral squamous cell carcinomas (OSCC) but not in normal mucosa. Molecular changes associated to early carcinogenesis have been found in mucosa near carcinomas, which is considered a model to study field cancerization. The aim of the present study is to analyze NOS2 expression at the histologically normal margins of OSCC.
  
  
  METHODS
  Eleven biopsy specimens of OSCC containing histologically normal margins (HNM) were analyzed. Ten biopsies of normal oral mucosa were used as controls. The activity of NOS2 was determined by immunohistochemistry. Salivary nitrate and nitrite as well as tobacco and alcohol consumption were also analyzed. The Chi-squared test was applied.
  
  
  RESULTS
  Six out of the eleven HNM from carcinoma samples showed positive NOS2 activity whereas all the control group samples yielded negative (p=0.005). No statistically significant association between enzyme expression and tobacco and/or alcohol consumption and salivary nitrate and nitrite was found.
  
  
  CONCLUSIONS
  NOS2 expression would be an additional evidence of alterations that may occur in a state of field cancerization before the appearance of potentially malignant morphological changes.
authors: Departamento de Patología Oral, Facultad de Odontología. Pabellón Argentina, Ciudad Universitaria, Agencia 4, (5016) Córdoba, República Argentina, rmorelatto@gmail.com.
authors: Rosana
authors: R
authors: Morelatto
authors: María-Elina
authors: ME
authors: Itoiz
authors: Natalia
authors: N
authors: Guiñazú
authors: Daniel
authors: D
authors: Piccini
authors: Susana
authors: S
authors: Gea
authors: Silvia
authors: S
authors: López-de Blanc
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000201:enzymology* / Q000473:pathology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000201:enzymology* / Q000473:pathology; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis*
chemical_list: C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II