Aspirin prevents tumors in a murine model of familial adenomatous polyposis

Background. Both human and murine studies suggest that anti- inflammatory drugs prevent intestinal neoplasia. The purpose of this study was to investigate the role of aspirin as a chemopreventive agent for colorectal cancer. Methods. We administered aspirin to the Min/+ mouse, an animal with a germline mutation in Apc, a gene that is essential for normal epithelial cell growth and differentiation. Apc mutation increases cytoplasmic β-catenin, a regulatory protein associated with the cytoskeleton. Min/+ mice develop multiple intestinal adenomas and exhibit altered cell growth in the preneoplastic intestinal epithelium. Results. Aspirin decreased the rate of tumor formation in Min/+ mice by 44%. Aspirin also normalized enterocyte growth by increasing apoptosis and proliferation in the preneoplastic intestinal mucosa. Finally, aspirin produced a decrease in intracellular β-catenin levels, suggesting that modulation of this protein is associated with tumor prevention. Conclusions. These data confirm a role for aspirin in suppression of Apc-associated intestinal carcinogenesis.