Project description:Emerging data suggest that some high-risk subjects benefit more than others from preventive intervention. The goal of this study was to determine the efficacy of sulindac (Sul) and/or atorvastatin (Atorva) against spontaneous colorectal adenomas in Apc+/Min-FCCC mice in which the tumor-bearing status was known at the time of treatment initiation. Administration of Sul/Atorva to tumor-bearing mice led to a 43% reduction in the multiplicity of colorectal adenomas as compared to that of untreated tumor-bearing mice. Atorvastatin completely inhibited the formation of microadenomas in mice that were tumor-free at baseline, with associated decreases in the expression of inflammatory mediators observed. Expression of Hoxb13 and Rprm was enhanced significantly following Sul/Atorva treatment, suggesting the importance of cell cycle regulation in colon tumor inhibition. The tumor status of animals at treatment initiation dictates response to atorvastatin, sulindac and Sul/Atorva. The tumor inhibition observed with Sul/Atorva in tumor-bearing mice was greater than that achieved with either agent alone.
Project description:Chemoprevention is a pragmatic approach to reduce the risk of colorectal cancer, one of the leading causes of cancer-related death in western countries. In this regard, maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, is known to inhibit proliferation and induce apoptosis in colon cancer cell lines without affecting normal intestinal cells. The present study evaluated the chemopreventive efficacy and associated mechanisms of maslinic acid treatment on spontaneous intestinal tumorigenesis in Apc(Min/+) mice. Twenty-two mice were randomized into 2 groups: control group and MA group, fed with a maslinic acid-supplemented diet for six weeks. MA treatment reduced total intestinal polyp formation by 45% (P<0.01). Putative molecular mechanisms associated with suppressing intestinal polyposis in Apc(Min/+) mice were investigated by comparing microarray expression profiles of MA-treated and control mice and by analyzing the serum metabolic profile using NMR techniques. The different expression phenotype induced by MA suggested that it exerts its chemopreventive action mainly by inhibiting cell-survival signaling and inflammation. These changes eventually induce G1-phase cell cycle arrest and apoptosis. Moreover, the metabolic changes induced by MA treatment were associated with a protective profile against intestinal tumorigenesis. These results show the efficacy and underlying mechanisms of MA against intestinal tumor development in the Apc(Min/+) mice model, suggesting its chemopreventive potential against colorectal cancer.