DNA once dismissed as 'noise' reveals new bacterial species in prostate cancer patients

Researchers from the University of East Anglia have discovered the genetic blueprints of 18 new bacterial species in prostate cancer patients. Most of these bacteria were found in the mouth, including new types of Porphyromonas and Treponema. The study, published in npj Biofilms and Microbiomes, utilized the leftover sequencing data from human DNA research, allowing the identification of these bacteria without additional costs or sample collection.

The discovery provides new insights into the microbial composition of cancer patients and may uncover links that improve understanding of how cancer develops. The study was part of the Pan Prostate Cancer Group (PPCG), a global collaboration involving researchers from nine countries and over 2,000 prostate cancer samples. The team recovered 249 near-complete bacterial genomes from 194 prostate cancer patients, with 24 of these not matching any known species.

One of the newly identified species was found to be almost an exact genetic match to a previously documented bacterium, confirming the validity of the discovery. The research highlights the potential of using existing cancer sequencing data to discover new bacteria, which could eventually lead to the development of tests for these organisms in clinical samples and a better understanding of their role in cancer progression.