Laura Bukavina, MD, MPH, a Urologic oncology fellow at Fox Chase Cancer Center, has been awarded the ASCO Genitourinary Conquer Cancer Merit Award. She presented the winning abstract, which characterizes the gut microbiome of patients with bladder cancer, at the 2022 ASCO Genitourinary (GU) Cancers Symposium in San Francisco. The broader project is a collaboration between researchers at Fox Chase and Case Western Reserve University School of Medicine/University Hospitals Cleveland Medical Center, where Dr. Bukavina completed her urology residency in 2021.
“Ninety percent of your immune system is within your gut,” said Dr. Bukavina. “And we see that some patients have an incredible response to chemotherapy, while others do not despite their tumor biology being very similar. This may in part be explained by the gut immune system and gut microbiome,” she said.
“It is incredible to think that as humans, only about 1% of our genomic composition is human, while the rest is derived from the microbiome. We suspected that the microbiome was different in patients with and without cancer, and this study proved that,” Dr. Bukavina added.
Laura Bukavina, MD, MPH
Analyzing the Response to Treatment
The research team now hypothesizes that the microbiome in the gut primes the immune system to respond differently to both cancer cells and chemotherapy. The group wants to explore whether certain bioactive small molecules produced by the microbiome can affect chemotherapy response. They are primed to interrogate this hypothesis now based on Dr. Bukavina’s findings.
The goal of the project is to first identify and then influence specific microbes or metabolites that improve the response of patients with bladder cancer to chemotherapy and immunotherapy. The research Dr. Bukavina presented at the ASCO GU symposium is the first step toward this goal.
Dr. Bukavina and her mentor, Phillip Abbosh, MD, PhD, Assistant Professor in the Molecular Therapeutics Research Program at Fox Chase, compared the microbiomes of patients with bladder cancer and a cancer-free control group by collecting and analyzing stool samples from both groups. “Dr. Bukavina showed great initiative in developing and executing this study, which is addressing very important questions. Her work is certainly deserving of this prestigious honor,” Dr. Abbosh said.
If they found no difference between the two groups, then there would be no clear route for intervention. However, they found significantly larger quantities of two bacteria—Campylobacter and Fusobacterium—in the samples from the patients with bladder cancer vs the samples from the control group.
“Now that we’ve identified the differences, the next step is to look at the microbiome of bladder cancer patients who responded to chemotherapy vs patients who did not respond to chemotherapy,” Dr. Bukavina said.
Disclosure: The study, “Characterization and Functional Analysis of Microbiome in Bladder Cancer,” was funded by the Case Comprehensive Cancer Center Microbiome Grant P30CA043703, issued by the National Cancer Institute within the National Institutes of Health.