Harnessing the intestinal microbiome for optimal therapeutic immunomodulation

Area of Science:

• Oncology
• Immunology
• Microbiome Research

Background:

• Cytotoxic agents in cancer therapy often modulate the immune system for tumoricidal activity.
• The role of the intestinal microbiota in mediating the efficacy of anticancer treatments is increasingly recognized.

Purpose of the Study:

• To provide evidence that the intestinal microbiota can trigger both innate and adaptive immunity against tumors.
• To elucidate the mechanisms by which gut commensals influence the effectiveness of chemotherapy and immunotherapies.

Main Methods:

• Investigated the impact of alkylating agents (e.g., cyclophosphamide) on intestinal permeability and bacterial translocation.
• Examined the role of gut commensals in modulating the tumor microenvironment during platinum salt or TLR9 agonist therapies.
• Assessed the influence of bacterial components like lipopolysaccharide (LPS) on myeloid cell function and TNF production.

Main Results:

• Alkylating agents increase intestinal permeability, leading to bacterial translocation and the activation of pTh17 and memory Th1 cells.
• Gut microbiota components alter the tumor microenvironment, affecting redox balance and myeloid cell TNF production.
• Antibiotics were shown to potentially compromise the efficacy of specific chemotherapeutic and immunomodulatory regimens.

Conclusions:

• The intestinal microbiota is a critical factor in the efficacy of various anticancer treatments, including chemotherapy and immunotherapy.
• Interventions targeting the gut microbiota could enhance anti-tumor immunity and treatment outcomes.
• The use of antibiotics may interfere with the therapeutic benefits of certain cancer treatments, highlighting the importance of the gut microbiome in oncology.