ORLANDO, FL (April 6, 2011) Numerous studies show that non-steroidal anti-inflammatory drugs (NSAIDs) reduce the risk of colon cancer. However, animal studies testing the NSAID naproxen or its derivative, NO-naproxen, have focused primarily on chemically-induced tumor formation. Now, researchers at Fox Chase Cancer Center find that naproxen and NO-naproxen reduce tumor formation in a strain of mutant mice that spontaneously develop colon tumors. The data also suggest that naproxen blocks a gatekeeper step that initiates tumor formation.
Margie Clapper, PhD, Co-Leader of the Cancer Prevention and Control Program at Fox Chase, will present the data in a late-breaking abstract session at the AACR 102nd Annual Meeting 2011 on Wednesday, April 6.
"There is a major effect on the very small lesions, about a 90% reduction in the mutant mice treated with naproxen compared with control animals," says Clapper. "That tells us this drug may be very appropriate for intervening early in people, far in advance of the development of large tumors. We might be able to have a significant impact on the very early and small lesions, thus reducing the morbidity associated with the disease."
Scientists have shown previously that both naproxen and NO-naproxen kill colon cancer cells in culture, with NO-naproxen appearing to be more powerful than naproxen. In the current study, the team fed mice genetically predisposed to spontaneously develop colon tumors either regular food or food supplemented with high- or low-dose naproxen or high- or low-dose NO-naproxen. After 45 days, they found that mice fed low-dose naproxen had 70.3% fewer small tumors than the control animals and mice fed low-dose NO-naproxen had 64.0% fewer tumors than control animals. Moreover, a 89.3% reduction in very small tumors, known as microadenomas, was observed when mice were fed high-dose naproxen.
Although Clapper and first author Wen-Chi Chang, PhD, Assistant Research Professor
|Contact: Diana Quattrone|
Fox Chase Cancer Center