J Urol. 2020 Aug 28:101097JU0000000000001336. doi: 10.1097/JU.0000000000001336. Online ahead of print.
PURPOSE: The dogma that urine is sterile has been overturned and dysbiosis of the urinary microbiome has been linked to many urological disorders. We tested the hypothesis that the urinary microbial composition may be different between men with or without bladder cancer in catheter-collected urines, bladder washouts and midstream voided urines, and may be dependent on tumor staging.
MATERIALS AND METHODS: Liquid samples were collected from bladder cancer male patients and sex/age-matched non-neoplastic controls. Total DNA was extracted and processed for 16S rRNA gene sequencing. Bioinformatic analysis for microbial classification was performed to assess diversity and variations.
RESULTS: The urinary microbiome associated with catheter urines of bladder cancer patients was characterized by a significantly increased abundance of Veillonella (p= .04) and Corynebacterium (p= .03) and decreased Ruminococcus (p= .03) compared to controls, with differences exacerbating with disease progression. Compared to catheterized urines, bladder cancer washouts showed the specific increase of some taxa, like Burkholderiaceae (p= .014), whereas midstream urines were enriched in Streptococcus (p< .0001), Enterococcus (p< .0001), Corynebacterium (p= .038), and of Fusobacterium (p< .0001).
CONCLUSIONS: The bladder is colonized by endogenous bacteria and microbial modifications characterize the microbiome of bladder cancer patients. Different microbial compositions can be characterized by changing sampling strategy. These results pave the way for exploring new diagnostic and therapeutic options based on the manipulation of the bacterial community.