COX-2 inhibition suppresses gastric cancer in rats

Treatment with the specific cyclooxygenase 2 (COX-2) inhibitor celecoxib suppresses chemically induced gastric tumors in rats, scientists report in the February issue of the journal Gut. “This finding lends further support to the use of COX-2 inhibitors in the chemoprevention of gastric cancer,” they write.

Overexpression of COX-2 is often seen in gastric cancer and is thought to play a key role in gastric carcinogenesis, Dr. Joseph J. Sung, from the Chinese University of Hong Kong, noted in comments to Reuters Health.In the current study, 86 male Wistar rats were allocated to 6 different treatment groups. One group received water only (the control group), while the other five received the gastric cancer-inducing agent, N-methyl-N-nitro-N-nitrosaguanidine (MNNG) in drinking water plus sodium chloride to enhance gastric cancer development. These rats then received indomethacin (3 mg/kg/day), celecoxib (5, 10, or 20 mg/kg/day) or no further treatment.While indomethacin did not protect the animals from gastric cancer, celecoxib in the 10-mg dose led to an “impressive” reduction in tumor incidence (56%) and multiplicity (80%). as well as a 1169-fold reduction in tumor volume, Dr. Sung told Reuters Health.The higher celecoxib dose did not add appreciably to the chemopreventive effects, and the lower dose did not protect the animals. The 10-mg celecoxib dose in rats is comparable to the usual 200 to 400 mg/day dose in humans, the authors note.”This study provides strong evidence that COX-2 inhibitors can prevent gastric cancer in rats,” Dr. Sung said. Whether this result can be translated into clinical benefit in humans deserves investigating, he added.(Source: Gut 2004;53:195-200: Reuters Health: February 13, 2004: Oncolink)