The gut microbiota associated with high-Gleason prostate cancerOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study examined whether gut microbiota composition is associated with high-grade (high-Gleason) prostate cancer in men undergoing prostate biopsy. The researchers had previously found in mouse models that intestinal bacteria and their short-chain fatty acid (SCFA) metabolites promote prostate cancer growth. Building on that finding, they used 16S rRNA gene sequencing to compare gut microbiota profiles between men with high-risk prostate cancer and men with negative or low-risk biopsy results. They then tested whether a microbiota-based index could help detect high-risk disease.
Who was studied?
The study included 152 Japanese men undergoing prostate biopsies for suspected prostate cancer, of whom 96 had cancer and 56 did not. Participants were randomly split into a discovery cohort of 114 samples and a test cohort of 38 samples. Within these cohorts, men were grouped as high-risk (Grade group 2 or higher prostate cancer) versus negative or low-risk (negative biopsy or Grade group 1 cancer).
What were the most important findings?
The relative abundances of Rikenellaceae, Alistipes, and Lachnospira, all SCFA-producing bacteria, were significantly increased in the high-risk group compared with the negative or low-risk group. Using least absolute shrinkage and selection operator (LASSO) regression, the researchers identified an index based on 18 bacterial genera that distinguished high-risk prostate cancer from lower-risk or negative cases. In the discovery cohort, this microbiota-based index detected high-risk disease more accurately than the prostate specific antigen (PSA) test, with an area under the curve of 0.85 versus 0.74.
What are the greatest implications of this study?
These findings support a link between gut microbiota, particularly SCFA-producing bacteria, and more aggressive prostate cancer in humans, consistent with prior mouse model results. A gut microbiota based index may offer a noninvasive tool that outperforms PSA alone for identifying men with high-risk prostate cancer. This suggests the gut microbiome could eventually inform risk stratification and biopsy decision-making for men undergoing prostate cancer screening, pending further validation.