Expression of cyclooxygenase-2 and microsomal prostagalandin E synthase-1 in head and neck squamous cell carcinoma

Objective: Our aim was to examine the expression of COX-2 and microsomal prostaglandin E synthase-1 (mPGES-1), and compare the results with clinical data. Patients and methods: Expression of COX-1, COX-2, and mPGS-1 was evaluated by immunohistochemistry in head and neck squamous cell carcinoma (HNSCC) from 25 patients and mRNA levels were determined by the quantitative reverse transcription polymerase chain reaction. Results: COX-2 overexpression was noted in tumor cells from 19 of the 25 carcinoma patients and mPGES was expressed by tumor cells from 21 patients. Localization of COX-2 and mPGES-1 was very similar, and well-differentiated tumors showed stronger expression than poorly/moderately differentiated tumors. The COX-2/GAPDH and mPGES/GAPDH mRNA ratios were significantly higher in well-differentiated carcinomas and NO patients. Conclusions: There was overexpression of COX-2 and its downstream enzyme mPGES-1, and their localization in tumor cells was similar, suggesting that these enzymes play both an important role in the development and proliferation of HNSCC. Furthermore, COX-2 and mPGES-1 were strongly expressed by well-differentiated carcinomas, suggesting their involvement in the differentiation of cancer. (C) 2009 Elsevier Ireland Ltd. All rights reserved.