Chemoprevention of breast cancer in rats by celecoxib, a cyclooxygenase 2 inhibitor

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been observed to reduce the relative risk of breast cancer. This prompted our investigation of the chemopreventive potential of celecoxib, a specific cyclooxygenase 2 blocker , against mammary carcinogenesis induced by 7,12-dimethylbenz(a)anthracene in female Sprague Dawley rats. Treatment with celecoxib was examined and co mpared to treatment with the general NSAID, ibuprofen, and to a control gro up receiving only dimethylbenz(a)anthracene. Dietary administration of cele coxib (1500 ppm) produced striking reductions in the incidence, multiplicit y, and volume of breast tumors relative to the control group (68%, 86%, and 81%, respectively; P < 0.001), Ibuprofen also produced significant effects , but of lesser magnitude (40%, 52%, and 57%, respectively; P < 0.001), The se results help confirm the chemopreventive activity of NSAIDs against brea st cancer and provide the first evidence that a cyclooxygenase 2 blocking a gent, celecoxib, possesses strong chemopreventive activity against mammary carcinogenesis.