Overexpression of cyclo-oxygenase 2 in squamous cell carcinoma of the hypopharynx

Hum Pathol. 2002 Jan;33(1):100-4. doi: 10.1053/hupa.2002.30187.


Upregulation of cyclo-oxygenase 2 (COX-2) expression is frequently found in a variety of human cancers. In this study, we examined COX-2 expression in squamous cell carcinoma of the hypopharynx. COX-2 messenger RNA (mRNA) analyzed by reverse-transcription polymerase chain reaction was detected in 87% (20 of 23) of tumor tissues. Expression of COX-2 protein was examined by Western blot analysis. COX-2 protein levels were increased in tumor tissues and correlated with the expression level of mRNA. Immunohistochemical study was performed to detect the subcellular localization of COX-2. Our results showed that COX-2 was predominantly detected in cancer cells, and the staining pattern was cytoplasmic. Several histologically normal adjacent tissues obtained from these patients were also investigated. We found that COX-2 mRNA was detectable in these tissues. However, COX-2 mRNA and protein levels were lower in these tissues than in tumor specimens. In contrast, COX-2 mRNA and protein levels in normal oral mucosa obtained from healthy volunteers were very low or undetectable. The frequency of COX-2 overexpression was significantly higher in the N1-N3 group than in the N0 group. These results suggest that overexpression of COX-2 is linked with increased lymphatic invasion in hypopharyngeal carcinoma. Collectively, these results suggest that overexpression of COX-2 is a frequent phenomenon in hypopharyngeal carcinoma and may play a role in tumorigenesis of this cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Blotting, Western
  • Carcinoma, Squamous Cell / enzymology*
  • Carcinoma, Squamous Cell / pathology
  • Cyclooxygenase 2
  • Female
  • Humans
  • Hypopharynx / enzymology*
  • Hypopharynx / pathology
  • Isoenzymes / biosynthesis*
  • Isoenzymes / genetics
  • Male
  • Membrane Proteins
  • Middle Aged
  • Pharyngeal Neoplasms / enzymology*
  • Pharyngeal Neoplasms / pathology
  • Prostaglandin-Endoperoxide Synthases / biosynthesis*
  • Prostaglandin-Endoperoxide Synthases / genetics
  • RNA / metabolism
  • RNA, Neoplasm / analysis
  • Reverse Transcriptase Polymerase Chain Reaction


  • Isoenzymes
  • Membrane Proteins
  • RNA, Neoplasm
  • RNA
  • Cyclooxygenase 2
  • PTGS2 protein, human
  • Prostaglandin-Endoperoxide Synthases