Recent studies have suggested that nitric oxide (NO) exerts various effects on aspects of tumor biology, including angiogenesis and metastasis. There have been, however, scanty reports on nitric oxide synthase (NOS) response for tumors of the head and neck. This study was carried out to assess the distribution of both endothelial NOS (eNOS) and inducible NOS (iNOS) in normal salivary gland tissue and in pleomorphic adenoma by using immunohistochemistry. In the present study, eNOS and iNOS were higher expressed in pleomorphic adenoma than adjacent normal salivary gland tissue, suggesting that up-regulation of this enzyme is associated with tumor progression. Additionally, eNOS and iNOS expression were higher in epithelial components than in mesenchymal components. Overall, iNOS expression was higher than eNOS expression in pleomorphic adenoma. In normal tissues adjacent to pleomorphic adenoma, iNOS expression was higher in the mesenchymal type than in the epithelial type of pleomorphic adenoma. It is suggested that NO may play a role in the tumorgenesis and propagation of pleomorphic adenoma.
Adenoma, Pleomorphic* ; Biology ; Head ; Immunohistochemistry ; Neck ; Neoplasm Metastasis ; Nitric Oxide Synthase* ; Nitric Oxide* ; Salivary Glands* ; Up-Regulation

Purpose: Vitamin D deficiency may cause bone loss and increased inflammation, which are well-known symptoms of periodontal disease. This study investigated whether serum 25-hydroxyvitamin D (25(OH)D) levels are associated with periodontal disease status and tooth loss. Methods: Cross-sectional data from 5,405 individuals aged ≥50 years (2,253 males and 3,152 females) were obtained from the 2008–2010 Dong-gu study, a prospective cohort study of risk factors for chronic diseases. Periodontal examinations were conducted to evaluate the number of remaining teeth, the periodontal probing depth (PPD), the clinical attachment level (CAL), and bleeding on probing. The percentages of sites with PPD ≥4 mm and CAL ≥4 mm were recorded for each participant. The severity of periodontitis was classified using the Centers for Disease Control and Prevention and the American Academy of Periodontology case definitions.Serum 25(OH)D levels were classified as reflecting severe deficiency, deficiency, insufficiency, or sufficiency. Multivariate linear regression analysis was performed to assess the associations of serum 25(OH)D levels with periodontal parameters and the number of remaining teeth after adjusting for confounders including age, smoking status, alcohol consumption status, month of blood collection, and physical activity. Multivariate logistic regression was used to evaluate the association between serum vitamin D levels and severe periodontitis. An overall statistical analysis and a stratified analysis by sex were performed. Results: Overall, the rates of severe deficiency, deficiency, insufficiency, and sufficiency were 6.5%, 67.9%, 22.4%, and 3.2%, respectively. After adjustment for confounders, vitamin D levels were directly associated with the number of remaining teeth, an association that was significant in males, but not in females. Sufficient serum 25(OH)D was associated with a low frequency of severe periodontitis. Conclusions This population-based cross-sectional study indicates that low serum 25(OH) D is significantly associated with tooth loss and severe periodontitis in Koreans aged 50 years and older.