Urinary microbiota diversity and composition in patients with advanced renal cell cancer

This study aims to investigate the role of urinary microbiota in renal cell carcinoma; we analysed urinary microbiota in kidney cancer patients and explored its potential role as biomarker.

Samples were collected from 49 males (28 patients planned to undergo systemic therapy and 21 healthy volunteers). Two samples were collected from each patient, one prior to treatment and one after 8 to 12 weeks of systemic therapy. Microbiota was analysed by 16S rRNA sequencing. Microbiota diversity, taxonomic composition and relative abundance were compared between groups and longitudinal samples.

Amplicon sequence variant (ASV) richness was higher in renal cancer patients (p = 0.042) than controls. Beta diversity also differed between patients and controls by means of Jaccard (p = 0.001), Bray-Curtis (p = 0.008), and nonweighted UniFrac metrics (p = 0.001). Acetobacter, Lacticaseibacillus, Alloscardovia, Brevibacterium and the family Propicionibactericeae had higher relative abundance in cancer patients, while Prevotella, Microbacterium and Sphingomonas were more abundant in controls. Beta diversity differed between pretreatment and posttreatment samples (p = 0.008). After systemic treatment, we found an increased relative abundance for Prevotella, Rothia, Bradyrhizobium, Methylobacterium/Methylobrum, Porphiromonas and Fusobacterium and a decreased one for the Burkeholderia-Caballeronia-Paraburkholderia group. Higher ASV richness was predictive of poor prognosis for RCC patients (p = 0.043) but not of treatment response.

Urinary microbiota in patients with renal cell carcinoma differed from controls. Changes in microbiota composition were observed after systemic treatment. Urinary microbiota should be further investigated as a potential biomarker in renal cell carcinoma.