Antibiotics in cancer patients: is the verdict still out?

Immune checkpoint inhibitors (ICI) have shown tremendous successes on treatment of multiple tumor malignancies, offering a valuable but rare commodity to both patients and researchers (1-3). As an important part of tumor immunotherapies, ICIs inspire the once-questioned idea that although inhibited our immune system is able to eliminate tumor cells in a similar way that it does to infectious microorganisms. ICIs can release the brakes imposed by the tumor on this fabulous capability, which then heightens the immune response against tumor cells.