The relationship between mucosal cyclooxygenase-2 (COX-2) expression and experimental radiation-induced mucositis

Oral Oncol. 2004 Feb;40(2):170-6. doi: 10.1016/s1368-8375(03)00148-9.


Although cycloooxygenase-2 (COX-2) is upregulated by factors associated with oral mucositis, its role in the pathogenesis of mucositis has not been studied. We investigated the kinetics of mucosal COX-2 expression following radiation exposure, and assessed its relationship to the development of oral mucositis in an established animal model using immunohistochemical endpoints. While little or no COX-2 expression was observed in unirradiated mucosa or in tissue taken 2 days after radiation, COX-2 expression was dramatic on days 10 and 16, especially in submucosal fibroblasts and endothelium. The kinetics of COX-2 expression paralleled mucositis severity. A burst of angiogenic activity was seen on day 21 following peak COX-2 expression. The kinetics of COX-2 expression relative to mucositis progression suggests that COX-2 is not a primary driver of radiation injury, but instead plays an amplifying role.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cricetinae
  • Cyclooxygenase 2
  • Fibroblasts / enzymology
  • Isoenzymes / metabolism*
  • Mesocricetus
  • Mouth Mucosa / blood supply
  • Mouth Mucosa / enzymology
  • Mouth Mucosa / radiation effects
  • Neovascularization, Pathologic / enzymology
  • Prostaglandin-Endoperoxide Synthases / metabolism*
  • Radiation Injuries, Experimental / enzymology*
  • Stomatitis / enzymology*
  • Stomatitis / etiology
  • Up-Regulation


  • Isoenzymes
  • Cyclooxygenase 2
  • Prostaglandin-Endoperoxide Synthases