Abstract 5204
Background
Microbiota has been linked to the development of multiple cancers through various mechanisms. In bladder cancer (BC), preliminary studies have found alterations in the urinary microbiota of patients with urothelial carcinoma in comparison with healthy individuals. However, the bladder microbiota (BMi) has not been explored. The aims of this study were to characterize the BMi in a cohort of BC patients, to explore differences in the BMi composition between tumor (T) and normal (N) mucosa, and to identify its correlation with clinicopathologic features.
Methods
A total of 58 samples obtained by cystectomy from 32 BC patients (frozen tumor tissues and normal appearing mucosa for 26 patients and 6 tumor tissues) from Hospital General de Elche Biobank (Spain) were included. DNAs isolated from bladder samples were used to perform 16S rRNA gene sequencing (V3 and V4 region). A paired-end 2 × 300 bp cycle run on Illumina MiSeq. Ribosomal Database Project Classifier was used for taxonomical assignment. Statistical analysis was performed using Rstudio platform. Groups of data were compared using Wilcoxon test and Mann Whitney test for 26T vs 26N (paired group) and 32T vs 26N (unpaired group), respectively.
Results
There were no statistically significant differences of diversity between T and N, but there were differences of richness between T and N at the genus level (Chao1 index, p = 0.049). Globally, the most abundant phylum was Firmicutes, followed by Bacteroidetes, Proteobacteria and Actinobacteria. We found that the microbial composition differed significantly between T and N in both groups. At the phylum level, while Cyanobacteria.Chloroplast (0.74% vs 2.44%; p = 0.025) was enriched in T, Actinobacteria were reduced in T. Principal component analysis based on the relative abundance of phylum (36.9% PC1 and 28.7% PC2 of explained variance) revealed a significant separation in bacterial community composition between tumor tissues associated with histological tumor grade (permanova grade =0.036).
Conclusions
Significant differences in the BMi composition associated with tumor grade were observed. Additional studies are needed to determine the role of BMi in the evolution of BC and its therapeutic implications.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5007 - Functional systemic CD4 immunity is required for clinical responses to PD-L1/PD-1 blockade therapy
Presenter: Miren Zuazo
Session: Poster Display session 3
Resources:
Abstract
5760 - Landscape of PD-L1 expression status in Chinese solid tumor patients.
Presenter: Yi Zhong
Session: Poster Display session 3
Resources:
Abstract
3733 - Anti-cancer and immunomodulatory effects of cobimetinib in triple negative breast cancer
Presenter: Chun-Yu Liu
Session: Poster Display session 3
Resources:
Abstract
4426 - Differential expression of immunoregulatory molecules and highly-associated cancer genes may provide novel insights into strategic trial design for therapeutics
Presenter: Jacob Adashek
Session: Poster Display session 3
Resources:
Abstract
2752 - Insights into the Tumor Immune Microenvironment using Tissue Phenomics to Drive Cancer Immunotherapy
Presenter: Martin Groher
Session: Poster Display session 3
Resources:
Abstract
5713 - Immune competent somatic mosaic model of colorectal cancer
Presenter: Stefania Napolitano
Session: Poster Display session 3
Resources:
Abstract
1898 - Genomic correlates of response to anti-PDL1 Atezolizumab in non-small-cell lung cancer OAK and POPLAR trials
Presenter: Hari Singhal
Session: Poster Display session 3
Resources:
Abstract
3246 - Erdafitinib (erda) versus available therapies in advanced urothelial cancer: A matching adjusted indirect comparison
Presenter: Yohann Loriot
Session: Poster Display session 3
Resources:
Abstract
3311 - High level of activity of Nivolumab anti-PD-1 immunotherapy and favorable outcome in metastatic/refractory MSI-H non-colorectal cancer: Results of the MSI cohort from the French AcSé program
Presenter: Christophe Tournigand
Session: Poster Display session 3
Resources:
Abstract
2314 - TP53 and ATM Co-mutation Predicts Response to Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer
Presenter: Yu Chen
Session: Poster Display session 3
Resources:
Abstract