The Interaction between Intratumoral Microbiome and Immunity Is Related to the Prognosis of Ovarian Cancer Original paper
Researched by:
-
Dr. Umar
Dr. Umar
Microbiome Signatures identifies and validates condition-specific microbiome shifts and interventions to accelerate clinical translation. Our multidisciplinary team supports clinicians, researchers, and innovators in turning microbiome science into actionable medicine.
Divine Aleru
Location
China
Sample Site
Ovary
Species
Homo sapiens
What was studied?
This research article examined how the intratumoral microbiome and immunity interact in ovarian cancer, establishing that this interaction is tied to prognosis. The study used RNA-sequencing data from TCGA to identify microbial signatures within tumors and assess their relationship to immune infiltration, clinical outcomes, and tumor microenvironment characteristics. By integrating microbial abundance with host immune gene expression, the authors created a microbiome-based prognostic model and conducted experimental validation focusing on Acinetobacter seifertii.
Who was studied?
The researchers analyzed 373 ovarian cancer patients from The Cancer Genome Atlas (TCGA). These individuals had available RNA-seq data, immune infiltration metrics, tumor microenvironment signatures, and survival outcomes. No specific demographic or clinical enrichment distinguished the immune-enriched versus immune-deficient groups, making the cohort broadly representative of advanced-stage ovarian cancer populations.
Most important findings
The study revealed two tumor microenvironment (TME) subtypes: immune-enriched and immune-deficient. Immune-enriched tumors contained more CD8⁺ T cells, M1 macrophages, higher stromal/immune scores, greater tumor mutational burden, and improved survival. Microbiome profiling uncovered significant microbial differences between these subtypes, with Proteobacteria, especially Pseudomonas species, dominant across samples. Beta-diversity clearly separated the groups (PCoA). A Cox model identified 32 prognostic microbial species whose presence predicted overall survival. Risk-associated species included Pseudomonas sp., Klebsiella michiganensis, Buchnera aphidicola, Veillonella nakazawae, and Corynebacterium jeikeium. The strongest protective species was Gemmatirosa kalamazoonesis. Five species correlated with M1 macrophages, notably Achromobacter deleyi and Microcella alkaliphila (positive), and Devosia sp. LEGU1, Ancylobacter pratisalsi, and Acinetobacter seifertii (negative).
Laboratory experiments validated that Acinetobacter seifertii inhibits macrophage migration, likely explaining its negative association with M1 abundance.
Key implications
This study demonstrates that intratumoral microbiota meaningfully shape ovarian cancer immunity and outcomes, establishing microbial signatures as promising prognostic biomarkers. The clear link between specific bacteria and immune cell infiltration, especially M1 macrophages, suggests microbial modulation as a potential therapeutic avenue. Distinct microbial metabolic pathways enriched in poor-prognosis tumors (e.g., PI3K-Akt signaling, taurine metabolism) provide additional mechanistic clues. Integrating microbiome data into clinical risk assessment could enhance patient stratification, refine immunotherapy responses, and guide the development of microbiome-targeted interventions.
Citation
Sheng D, Yue K, Li H, Zhao L, Zhao G, Jin C, Zhang L. The interaction between the intratumoral microbiome and immunity is related to the prognosis of ovarian cancer. Microbiology Spectrum. 2023;11(2):e03549-22. doi:10.1128/spectrum.03549-22