Characters of urinary microbiota in male patients with non-muscle invasive bladder cancer

Abstract

Objective To characterize the urinary microbial profile of male non-muscle invasive bladder cancer patients compared to healthy controls. Methods Between March, 2017 and September, 2017, mid-stream urine from 26 non-muscle invasive bladder cancer and 18 non-neoplastic controls were collected by the clean method, then centrifuged and processed for 16S rRNA gene sequencing. Sequencing reads were processed for evaluating alpha diversity and beta diversity using QIIME. LEfSe algorithm was performed to identify potential bacterial genera biomarker. Results The smoking cases were more in tumor group than those in control group(21 vs. 7, P<0.01). The urinary microenvironment of bladder cancer was characterized by increased bacterial richness (Observed species index, Chao1 index and Ace index, 125.77±69.64 vs.80.38±46.24; 142.82±76.74 vs. 90.68±47.62; and 147.92±77.68 vs. 88.19±45.38, all P<0.05) and by the enrichment of some bacterial genera (e.g., Acinetobacter and Anaerococcus). Significant difference in β diversity was found between cancer and non-cancer group(ANOSIM, P=0.009). A clear hierarchical clustering of cancer samples was observed, suggesting a common dysbiosis associated to bladder cancer. Conclusions Patients with non-muscle invasive bladder cancer exhibit a different microbial community compared to non-neoplastic controls, suggesting a possible pathophysiological correlation between microbiome and bladder cancer. Urinary microbial community may be associated with the prognosis of NMIBC. Key words: Non-muscle invasive bladder cancer; Urinary microbiome; Chronic inflammation