Researchers at Fred Hutchinson Cancer Center teamed up to show how bacteria could help tumors progress and resist treatment. One study showed that bacteria cluster within oral or colorectal cancer tumors and could be help tumor cells metastasize and duck under the immune system's radar. In a separate study, the group showed that some chemotherapeutics could also act as antimicrobials, and that the composition of a tumor's microbiome could help change how well chemotherapy works.