Gut microbial metabolites in cancer immunomodulation

Area of Science:

• Immunology
• Microbiology
• Oncology

Background:

• Gut microbiota metabolites are systemic immunoregulators shaping tumor immunity.
• Existing frameworks link metabolites to immune effects via receptor signaling and epigenetic remodeling.

Purpose of the Study:

• To advance a metabolite-immune pathway-cancer framework integrating diverse metabolites and their immune effects.
• To explore how microbial metabolites directly interact with T cells and modulate the tumor microenvironment.
• To compare tumor-specific metabolite-immune circuits and identify intervention targets.

Main Methods:

• Integration of evidence on short-chain fatty acids, tryptophan derivatives, bile acids, and polyamines.
• Analysis of metabolite-receptor interactions, including T-cell receptor ligation.
• Comparison of tumor-type specific patterns and application of multi-omics and imaging techniques.

Main Results:

• Metabolites recalibrate the tumor immune microenvironment by modulating antigen presentation, T-cell fitness, and myeloid cell polarization.
• Metabolite effects are context-dependent, influencing immune surveillance or suppression based on ligand-receptor pairing, dose, and tissue niche.
• Novel methods enable co-registration of metabolite exposure with immune-cell states for biomarker discovery.

Conclusions:

• Mapping tissue-specific metabolite-immune circuits is crucial for developing precision cancer immunotherapy.
• Microbial metabolites can be converted from correlative markers into therapeutic targets.
• Precision interventions like fecal microbiota transplantation and engineered microbes hold promise for improving immunotherapy efficacy.