Up-regulation of cyclooxygenase-2 expression in lymphocytic thyroiditis and thyroid tumors: significant correlation with inducible nitric oxide synthase.
To cast light on relations of cyclooxygenase-2 (COX-2) expression to lymphocytic thyroiditis and thyroid tumorigenesis, protein levels were immunohistochemically assessed and compared with inducible nitric oxide synthase (iNOS) in a total of 181 cases: follicular adenoma, 23; well-differentiated papillary carcinoma, 85; poorly differentiated papillary carcinoma, 25; anaplastic carcinoma, 7; and follicular carcinoma, 41. In addition, 72 specimens of normal follicular epithelia and 36 of lymphocytic thyroiditis were used as control samples. Immunohistochemical results were confirmed in 2 cases each of normal thyroid, lymphocytic thyroiditis, and well-differentiated and poorly differentiated papillary carcinoma, by Western blotting assay. Stepwise increments in overexpression of COX-2 and iNOS were revealed in epithelial cells of lymphocytic thyroiditis, follicular adenoma, and papillary carcinoma; normal thyroid epithelium showed little expression. A significant positive correlation between the 2 enzymes was found with all cases. Enhanced expression of both COX-2 and iNOS suggests important roles in the inflammatory processes underlying lymphocytic thyroiditis and thyroid tumorigenesis.
Nose
Fusako
F
Department of Pathology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
Ichikawa
Tsuwa
T
Fujiwara
Mutsunori
M
Okayasu
Isao
I
D000236:Adenoma / Q000201:enzymology; D015153:Blotting, Western; D002291:Carcinoma, Papillary / Q000201:enzymology; D051546:Cyclooxygenase 2; D004848:Epithelium / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000235:genetics* / Q000378:metabolism*; D008565:Membrane Proteins; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics* / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000201:enzymology*; D013967:Thyroiditis, Autoimmune / Q000201:enzymology*
D007527:Isoenzymes; D008565:Membrane Proteins; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases