Dr. Kathy McCoy, PhD, is a leading expert on the body’s relationship with the microbiome. She and her team are focused on harnessing the power of the microbiome to improve health and treat diseases. McCoy says to harness and direct that power scientists need to better understand the role bacteria play in regulating the immune system.
“Recent studies have provided strong evidence that gut microbiota can positively affect anti-tumour immunity and improve the effectiveness of immunotherapy in treating certain cancers, yet, how the bacteria were able to do this remained elusive, ” says McCoy.
“We found that these bacteria produce a small molecule, called inosine,” says Dr. Lukas Mager, MD, PhD, senior postdoctoral researcher in the McCoy lab and first author on the study. “Inosine interacts directly with T-cells and together with immunotherapy, it improves the effectiveness of that treatment, in some cases destroying all the colorectal cancer cells.”
The researchers then validated the findings in both bladder cancer and melanoma. The next step in this work will be to study the finding in humans. The three beneficial bacteria associated with the tumours in mice have also been found in cancers in humans.
“Identifying how microbes improve immunotherapy is crucial to designing therapies with anti-cancer properties, which may include microbials,” says McCoy.