COX-2 overexpression in canine tumors: potential therapeutic targets in oncology

Histol Histopathol. 2005 Oct;20(4):1309-12. doi: 10.14670/HH-20.1309.


Cyclooxygenases catalyze the initial, rate-limiting steps of prostaglandin synthesis from arachidonic acid. Two isoforms of this enzyme exist in mammalian and avian species: COX-1 and COX-2. COX-1 is constitutively expressed and is the major isoform of gastrointestinal tissue. COX-2 is induced in response to inflammatory stimuli. COX-2 has been implicated in carcinogenesis of several neoplasms. Furthermore, COX-2 over-expression has been noted in many solid tumours and has been correlated with a worse prognosis in colorectal cancer, non-small-cell lung cancer, mesothelioma and gastric cancer. In this review, the most recent findings on the mechanisms by which COX-2 promote tumorigenesis are discussed, with particular emphasis on the studies involving spontaneous canine neoplasms.

Publication types

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

MeSH terms

  • Animals
  • Cyclooxygenase 2 / biosynthesis*
  • Cyclooxygenase 2 / genetics*
  • Cyclooxygenase 2 Inhibitors / therapeutic use
  • Dog Diseases / enzymology*
  • Dogs
  • Neoplasms / drug therapy*
  • Neoplasms / enzymology*
  • Neoplasms / epidemiology


  • Cyclooxygenase 2 Inhibitors
  • Cyclooxygenase 2