Science 359, 91–97 (2018).

Science 359, 97–103 (2018).

Science 359, 104–108 (2018).

In the form of immunotherapy known as immune checkpoint inhibition, therapies are administered that release the breaks (i.e., checkpoints) on the immune system to activate it against cancer. This approach has had a major impact on cancer treatment, but not all individuals treated with this therapy respond.

Researchers from the United States and France found that the composition of the gut microbiome can influence an individual’s response to immune checkpoint inhibition. The researchers in France found that antibiotic treatment inhibits the effectiveness of this kind of immunotherapy treatment, and the US scientists found that patients with melanoma who did not respond to immune checkpoint inhibition drugs had an imbalance of gut flora, hampering their immune response against cancer.

In the future, the composition of the gut microbiome could be manipulated to enhance the effectiveness of immune checkpoint inhibition or used as a biomarker to gauge potential response.