Microplastics' Impact on the Development of AOM/DSS-Induced Colitis-Associated Colorectal Cancer in Mice

Area of Science:

• Environmental Health
• Gastroenterology
• Toxicology

Background:

• Growing evidence links microplastics (MPs) to adverse health effects.
• The role of MPs in carcinogenesis, particularly colorectal cancer, requires further investigation.

Purpose of the Study:

• To assess the impact of MPs on the development of colitis-associated colorectal cancer (CAC) in a mouse model.

Main Methods:

• Adult male C56BL/6 mice were used to establish an AOM/DSS-induced CAC model.
• One group received 5 μm polystyrene MPs (1.48 mg/kg/day) in drinking water for 12 weeks; the control group received untreated water.

Main Results:

• Mice exposed to MPs exhibited increased tumor nodules, higher tumor prevalence, enhanced inflammatory infiltration, and altered goblet and enteroendocrine cell content in the colon.
• No significant effects of MPs were observed on specific gene expression (claudins, mucins, Bax, Mki67) or serum cytokine levels (TNFα, IL-1β, IL-6, IL-10).

Conclusions:

• Microplastics promote CAC development in mice by exacerbating intestinal inflammation and compromising the epithelial barrier.
• MPs may act as an environmental cofactor contributing to the risk of colorectal cancer.