Related Experiment Video
Updated: Apr 28, 2026

An In Vitro Batch-culture Model to Estimate the Effects of Interventional Regimens on Human Fecal Microbiota
Published on: July 31, 2019
Three measurable and modifiable enteric microbial biotransformations relevant to cancer prevention and treatment
1Penny George Institute for Health and Healing, Abbott Northwestern Hospital, Minneapolis, Minnesota, United States.
Abstract:
Interdisciplinary scientific evaluation of the human microbiota has identified three enteric microbial biotransformations of particular relevance for human health and well-being, especially cancer. Two biotransformations are counterproductive; one is productive. First, selective bacteria can reverse beneficial hepatic hydroxylation to produce toxic secondary bile acids, especially deoxycholic acid. Second, numerous bacterial species can reverse hepatic detoxification-in a sense, retoxify hormones and xeonobiotics-by deglucuronidation. Third, numerous enteric bacteria can effect a very positive biotransformation through the production of butyrate, a small chain fatty acid with anti-cancer activity. Each biotransformation is addressed in sequence for its relevance in representative gastrointestinal and extra-intestinal cancers. This is not a complete review of their connection with every type of cancer. The intent is to introduce the reader to clinically relevant microbial biochemistry plus the emerging evidence that links these to both carcinogenesis and treatment. Included is the evidence base to guide counseling for potentially helpful dietary adjustments.
Insights
The human gut microbiota influences cancer through microbial biotransformations. Some bacteria produce toxic compounds, while others generate beneficial butyrate, impacting cancer development and treatment.
Area of Science:
- Microbiology
- Biochemistry
- Oncology
Background:
- The human microbiota plays a critical role in health and disease.
- Specific microbial biotransformations in the gut are linked to cancer development.
- Understanding these processes is crucial for therapeutic interventions.
Purpose of the Study:
- To evaluate key enteric microbial biotransformations relevant to human health and cancer.
- To explore the dual role of gut microbes in producing toxic metabolites and beneficial compounds.
- To connect these microbial activities with gastrointestinal and extra-intestinal cancers.
Main Methods:
- Interdisciplinary scientific evaluation of human microbiota.
- Analysis of specific bacterial biotransformations: bile acid deconjugation, hormone/xenobiotic deconjugation, and butyrate production.
- Review of existing evidence linking these biotransformations to various cancer types.
Main Results:
- Two counterproductive biotransformations identified: production of toxic secondary bile acids (e.g., deoxycholic acid) and retoxification via deglucuronidation.
- One productive biotransformation identified: production of anti-cancer butyrate by enteric bacteria.
- Relevance of these biotransformations to representative gastrointestinal and extra-intestinal cancers discussed.
Conclusions:
- Gut microbial biotransformations significantly impact cancer pathogenesis and treatment.
- Targeting microbial metabolism offers potential therapeutic strategies.
- Dietary adjustments can be counseled based on evidence linking microbial activity to cancer.
More Related Videos
07:05Important Endpoints and Proliferative Markers to Assess Small Intestinal Injury and Adaptation using a Mouse Model of Chemotherapy-Induced Mucositis
Published on: May 12, 2019
11:003D Flipwell Engineering for Developing Asynchronous Systems for Toxicologic and Immunomodulatory Therapies in Bacterial, Gut, and Immune Cells
Published on: October 17, 2025
Related Concept Videos
Microbial Bioremediation of Uranium
Drug Biotransformation: Overview
Drug Biotransformation: Overview
Factors Affecting Drug Biotransformation: Biological
Species differences: Variations in enzyme systems across species can cause disparities in drug metabolism. For instance, humans may metabolize certain drugs faster than rodents, altering therapeutic effects.
Strain differences: Genetic variations within a species can result in differing enzyme activity, impacting drug response and toxicity. For example, some mouse strains may...
Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase
Microorganisms in Medicine and Therapeutics