Overexpression of cyclooxygenase-2 correlates with cytoplasmic HuR expression in salivary mucoepidermoid carcinoma but not in pleomorphic adenoma.
BACKGROUND
The overexpression of cyclooxygenase (COX)-2 in several human carcinomas suggests that COX-2 is related to carcinogenesis. Although COX-2 expression has been shown to be up-regulated in carcinomas of the salivary gland, its mechanisms are not completely understood. HuR is an mRNA-binding protein that controls the stability of certain transcripts including COX-2.


METHODS
The expression of COX-2 and HuR was determined by immunohistochemistry in 28 cases of salivary pleomorphic adenoma and 18 cases of salivary mucoepidermoid carcinoma.


RESULTS
28.6% and 72.2% of the pleomorphic adenomas and mucoepidermoid carcinomas showed high COX-2 expression respectively. 35.7% of pleomorphic adenomas and 72.2% of mucoepidermoid carcinomas were tested positive for HuR in the cytoplasm of tumor cells. There was a correlation between a high COX-2 immunoreactivity and cytoplasmic HuR expression in mucoepidermoid carcinomas but not in pleomorphic adenomas.


CONCLUSIONS
This study suggests that cytoplasmic HuR is correlated with COX-2 expression in salivary mucoepidermoid carcinomas. In addition, the immunoreactivity of COX-2 and cytoplasmic HuR might be used to evaluate the nature of a borderline malignancy in the salivary glands.
Cho
Nam-Pyo
NP
Department of Oral Pathology, School of Dentistry and Institute of Oral Bioscience, Chonbuk National University, Jeonju, Korea.
Han
Hye-Suk
HS
Soh
Yunjo
Y
Son
Hyun-Jin
HJ
D008949:Adenoma, Pleomorphic / Q000201:enzymology / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000954:Antigens, Surface / Q000378:metabolism*; D018277:Carcinoma, Mucoepidermoid / Q000201:enzymology / Q000378:metabolism*; D016009:Chi-Square Distribution; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D012468:Salivary Gland Neoplasms / Q000201:enzymology / Q000378:metabolism*
D000954:Antigens, Surface; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; C098770:ELAVL1 protein, human; D009363:Neoplasm Proteins; D016601:RNA-Binding Proteins; D051546:Cyclooxygenase 2