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Updated: May 12, 2026
11:22
Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing
Published on: October 15, 2019
Gut Microbiota and Extraintestinal Cancers: Mechanistic Insights and Microbiome-Targeted Interventions
Rishi Chowdhary1, Manjeet Kumar Goyal2, Kirti Arora2
1Department of Medicine MetroHealth Medical Center Cleveland Ohio USA.
Summary
The gut microbiome influences cancer development and treatment. Microbial imbalances (dysbiosis) impact immunity and therapeutic responses, highlighting potential for microbiome-targeted cancer interventions.
Area of Science:
- Microbiology
- Oncology
- Immunology
Background:
- The gut microbiota, a complex ecosystem of microorganisms, is crucial for host health, immunity, and metabolism.
- Microbial imbalances (dysbiosis) are linked to both gastrointestinal and extraintestinal cancers.
- The gut-microbiota-cancer axis involves microbial metabolites influencing carcinogenesis via genetic, epigenetic, and immune pathways.
Purpose of the Study:
- To explore the multifaceted role of the gut microbiota in the development and progression of extraintestinal malignancies.
- To investigate how gut microbial dysbiosis affects host immunity and anti-tumor responses.
- To review the potential of microbiome-targeted interventions in cancer therapy.
Main Methods:
- Review of mechanistic studies on the gut-microbiota-cancer axis.
- Analysis of germ-free model data on immune cell differentiation and anti-tumor immunity.
- Examination of evidence linking specific gut taxa and metabolites to various cancers (breast, lung, melanoma, prostate).
- Assessment of emerging microbiome-targeted therapies like fecal microbiota transplantation (FMT) and probiotics.
Main Results:
- Gut microbiota signals are essential for proper T-cell differentiation and anti-tumor immunity.
- Dysbiosis can impair the efficacy of immune checkpoint inhibitors (ICIs).
- Specific microbes (e.g., Bifidobacterium, Akkermansia) may enhance cancer treatment responses.
- The gut microbiota influences diverse cancers through mechanisms like estrogen metabolism, the gut-lung axis, and androgen receptor signaling.
Conclusions:
- The gut microbiota possesses both oncogenic and tumor-suppressive potential, impacting systemic health.
- Understanding the gut-microbiota-cancer interplay is key to developing novel diagnostic and therapeutic strategies.
- Microbiome-targeted interventions show promise but require further research to overcome challenges like individual variability.
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