Abstract
Background: The impact of the antiinflammatory agent 5-aminosalicylic acid (5-ASA) on the risk for colitis-associated colorectal cancer remains controversial. The chemopreventive activity of 5-ASA was evaluated in the Swiss Webster model of azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colitis-associated neoplasia. Methods: Mice were injected with AOM (7.4 mg/kg i.p.) and randomized to receive either vehicle or 5-ASA (75, 150, and 225 mg/kg) for the remainder of the study. DSS treatment began at 9 weeks of age and continued for 3 cycles. At the time of sacrifice (18 weeks of age), the entire colon and rectum were processed for histopathologic examination. Results: An inverse trend was observed between dose and multiplicity of colonic dysplasias in all drug-treated groups (P = 0.03), with animals receiving 75 mg/kg 5-ASA exhibiting 56% of the number of dysplasias of the AOM/DSS controls (mean = SEM: 7.6 ± 1.4 and 13.6 ± 2.7, respectively). Administration of 75 mg/kg 5-ASA decreased both the mean multiplicity of flat dysplasias (1.8 ± 0.4 for drug-treated versus 5.6 ± 1.2 for AOM/DSS control) and the burden of polypoid dysplasias (tumor burden: 6.7 ± 2.7 for drug-treated versus 14.9 ± 3.9 units for AOM/DSS controls) significantly (P = 0.002 and 0.04, respectively). Inflammation was least severe in the 75 mg/kg group, which exhibited the fewest number of colorectal tumors. Conclusions: These data suggest that low-dose 5-ASA may be efficacious in preventing colitis-associated dysplasias and provide strong support for optimizing this therapy for the prevention of colonic neoplasms in patients with ulcerative colitis.
Original language | English |
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Pages (from-to) | 1341-1347 |
Number of pages | 7 |
Journal | Inflammatory Bowel Diseases |
Volume | 14 |
Issue number | 10 |
DOIs | |
State | Published - 2008 |
Keywords
- 5-Aminosalicylic acid
- Colorectal neoplasia
- Dextran sulfate sodium
- Mouse model
- Ulcerative colitis