Overexpression of cyclooxygenase-2 in nasopharyngeal carcinoma and association with lymph node metastasis

Oral Oncol. 2005 Oct;41(9):903-8. doi: 10.1016/j.oraloncology.2005.05.003.


Cyclooxygenase-2 (COX-2) has been shown to be involved in multiple steps of carcinogenesis. In this study, we examined COX-2 expression in nasopharyngeal carcinoma (NPC). COX-2 mRNA analyzed by reverse-transcription polymerase chain reaction (RT-PCR) was detected in 66% (16 of 24) of tumor tissues. Western blot analysis demonstrated that COX-2 protein level was increased in tumor tissues and was correlated with the expression level of mRNA. Immunohistochemical study showed that COX-2 was predominantly detected in cancer cells, and the staining pattern was cytoplasmic. Ten histologically normal nasopharyngeal tissues obtained from nasopharyngeal hyperplasia were also investigated. We found that COX-2 mRNA was detectable in three tissues and the COX-2 protein level was very low. The frequency of COX-2 overexpression was significantly higher in patients of the N1-N3 group than in patients of the N0 group (P=0.006). Taken together, these data suggest that COX-2 is overexpressed and is associated with increased lymphatic invasion in NPC.

Publication types

  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Adult
  • Aged
  • Blotting, Western
  • Carcinoma / enzymology*
  • Carcinoma / secondary
  • Cyclooxygenase 2 / metabolism*
  • Female
  • Humans
  • Immunohistochemistry
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Nasopharyngeal Neoplasms / enzymology*
  • RNA, Messenger / analysis
  • RNA, Neoplasm / analysis
  • Reverse Transcriptase Polymerase Chain Reaction


  • RNA, Messenger
  • RNA, Neoplasm
  • Cyclooxygenase 2