Diagnostic and prognostic potential of the microbiome in ovarian cancer treatment response Original paper

What was studied?

The study investigated the diagnostic and prognostic potential of the microbiome in ovarian cancer treatment response, examining how microbial communities across the female reproductive tract, peritoneal fluid, urine, stool, and omentum differ between women with ovarian cancer and those undergoing hysterectomy for benign conditions. This research explored whether specific microbial signatures could distinguish benign from malignant disease and whether these microbial patterns relate to ovarian cancer stage, grade, histology, or treatment outcomes. The authors conducted 16S rRNA gene sequencing on 751 samples from 64 women, identifying microbial taxa whose enrichment or depletion may serve as early indicators of ovarian cancer or predictors of treatment response. The focus keyphrase diagnostic microbiome biomarkers for ovarian cancer aligns strongly with this aim, appearing here as the study’s primary thematic emphasis.

Who was studied

The study enrolled 64 women undergoing hysterectomy at Mayo Clinic: 30 with benign gynecologic conditions and 34 with ovarian cancer. The ovarian cancer cohort included a spectrum of disease stages (I–IV), grades, and histologic subtypes (high-grade serous being most common). Samples were collected pre-treatment, making all microbiome measurements reflective of baseline, treatment-naïve states. Women with recent antibiotic exposure, pregnancy, or morcellation procedures were excluded. The cohorts were broadly similar in age, menopausal status, and BMI, strengthening the validity of observed microbiome differences.

Most important findings

Across body sites, the ovarian cancer microbiome differed substantially from benign controls. In the lower reproductive tract (vagina/cervix), ovarian cancer showed higher α-diversity and enrichment of pathogenic taxa such as Corynebacterium tuberculostearicum, Facklamia hominis, Ruminococcus faecis, Dialister, Prevotella, and Peptoniphilus. These taxa were consistently enriched across multiple reproductive sites in ovarian cancer patients. Notably, these same genera were depleted in advanced-stage and high-grade disease, suggesting accumulation early in tumorigenesis followed by loss with disease progression. Microbiome signatures associated with grade and histology echoed these patterns. Low-grade disease demonstrated enrichment of Streptococcus infantis, Fusobacterium nucleatum, Escherichia coli, and Faecalibacterium prausnitzii, whereas high-grade cases showed depletion. Serous carcinoma also carried distinct signatures, including elevated Lactobacillus iners and Actinomyces turicensis. Prognostically, treatment-sensitive tumors showed distinct β-diversity patterns in Fallopian tube, ascites, and urine samples compared to resistant or refractory disease. Patients with adverse clinical events (recurrence or death) exhibited enrichment of Lactobacillus gasseri, Dialister invisus, Blautia pseudococcoides, Veillonella nakazawae, and Bacteroides ovatus, suggesting microbial involvement in chemoresistance or immune modulation.

Key implications

This work suggests that diagnostic microbiome biomarkers for ovarian cancer may enable earlier detection than current clinical methods. The enrichment of pathogenic and immunomodulatory taxa early in disease points to potential microbial drivers or amplifiers of carcinogenesis. The depletion of these taxa in advanced disease indicates a temporal microbial shift that could serve as a biological clock for disease progression. Prognostically, microbial signatures obtained at diagnosis could help stratify patients by likelihood of responding to chemotherapy. These findings highlight the microbiome’s potential as a clinical tool for both detection and individualized therapy planning.

Citation

Asangba AE, Chen J, Goergen KM, et al. Diagnostic and prognostic potential of the microbiome in ovarian cancer treatment response. Scientific Reports. 2023;13:730. doi:10.1038/s41598-023-27555-x