Research points to gaps in literature for bladder cancer and the microbiome

In this video, Ilaha Isali, MD, MSc, and Laura Bukavina, MD, MPH, MSc, discuss gaps in the literature relating to the microbiome and bladder cancer. They are authors of the recent Urologic Oncology paper “State-of-the-Art review: The Microbiome in Bladder Cancer.” Isali is a urology resident at Weill Cornell Medicine in New York, New York, and Bukavina is an assistant professor of urologic oncology at Cleveland Clinic Glickman Urologic Institute and the translational science lead in GU oncology at Cleveland Clinic Lerner College of Medicine in Cleveland, Ohio.

Transcription:

You noted gaps in the literature, particularly regarding the impact of bladder cancer treatments on the microbiome and immunotherapy-related toxicities. What do you see as the biggest challenges or limitations in studying these aspects, and how might they be addressed in future research?

Isali: We recently published on paper with Dr Laura Bukavina. She is the leader of this research. We also highlighted several limitations [with] microbiome research. In this review article, we specifically focused on challenges in researching the microbiome in bladder cancer. I will highlight those several limitations that currently hinder our understanding of how bladder cancer treatments, particularly immunotherapies, affect the microbiome. [The] first thing is methodological variability. Studies often lack standardized methods for sample collection, DNA extraction, and sequencing, leading to inconsistent findings. Second, [there are] contamination risks. Low biomass samples, such as those from bladder tissue or urine samples, are very prone to contamination, which complicates the interpretation of microbiome signatures. And of course, dynamic microbiome changes, I would say, treatments, specifically chemotherapies or intravesical therapies, can induce rapid changes in the microbiome, which requires longitudinal studies for comprehensive insights. Future research should focus on standardizing methodologies, incorporating multi-omics approach and utilizing preclinical models that closely mimic the patient's specific conditions. This hopefully will help delineate the links between microbiome dysbiosis and cancer progression and also the treatment outcomes.

Bukavina: There are significant gaps. The majority of the studies in the microbiome within the concept of bladder cancer have been done in terms of characterization studies. Those are the studies that you're looking at potential differences between your healthy controls or the patients with bladder cancer. Those are sort of the baseline grade studies to have, but I really see that we haven't made much of a leap compared with lung cancer or melanoma trials in understanding above just beyond the baseline differences in microbiome. Patients who are receiving treatment for their bladder cancer, whether it's localized or systemic treatment, how do those baseline differences alter their response to therapy? I think the biggest challenge is we haven't figured out what specifically we should be doing in bladder and the microbiome. Should we be doing urine? Should we be doing gut? Should we be doing a combination of both? Studying the microbiome overall is challenging because it's dirty science. You have to be incredibly careful with contamination, and it becomes challenging to understand what's real and what's not. Just because we find an association, it doesn't necessarily mean it translates to a clinical effect.

This transcript was AI generated and edited by human editors for clarity.