Gut Microbiota-Driven Secondary Bile Acid Synthesis Enhances Colorectal Cancer Risk Linked to Western Dietary Patterns

Category	Detail
Condition	Colorectal Cancer (CRC)
Key Mechanisms	Increased production of secondary bile acids (BAs) by gut microbiota, particularly deoxycholic acid (DCA), linked to Western dietary patterns.
Target Population	Individuals at risk of sporadic colorectal cancer, particularly those consuming a Western diet.
Care Setting	Preclinical models and dietary intervention studies.

Western diet exacerbates colorectal tumorigenesis in APC 1311/+ pigs.
Increased levels of faecal secondary BAs, especially DCA, correlate with enhanced epithelial cell proliferation.
Specific 7α-dehydroxylating bacteria induce DCA production and promote colonic epithelial cell proliferation.
7αDH+ bacteria causally linked to increased colon tumor burden in gnotobiotic models.
Colestyramine administration can reverse the effects of elevated secondary BAs.

Detection of Clostridium scindens and related 7αDH+ species in stool may identify high-risk individuals.

Personalized dietary interventions to reduce secondary BA production in individuals at risk of CRC.

Monitor levels of secondary BAs in individuals with dietary risk factors for CRC.

High-fat, low-fiber diets are associated with increased risk of sporadic colorectal cancer.

Individuals at high risk for colorectal cancer due to dietary patterns.

Interventions targeting gut microbiota and secondary BA production may be beneficial.

Clinical Scorecard: Gut Microbiota-Driven Secondary Bile Acid Synthesis Enhances Colorectal Cancer Risk Linked to Western Dietary Patterns