Cancer: Are probiotics making immunotherapy less effective?

Studies of the gut microbiome have found some unusual results. Checkpoint inhibitors are one type of immunotherapy that affect cancer cells' ability to dodge immune system attacks. However they only work for 20-30% of people with cancer. The gut microbiome is able to control the immune system, so is it possible that this is impacting immunotherapy success rates? Interesting results published from the Parker Institute for Cancer Immunotherapy, being presented today at the American Association for Cancer Research, Atlanta, USA.