From CancerSupportInternational.com

International News
Microbes Play Role in Anti-Tumor Response
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Nov 16, 2015, 10:51

Gut microbiome composition can influence the effectiveness of cancer immunotherapy in mice.
http://www.the-scientist.com/?articles.view/articleNo/44418/title/Microbes-Play-Role-in-Anti-Tumor-Response/

The presence of certain types of gut microbes in mice can boost the anti-tumor effects of cancer immunotherapy, according to two studies from independent research teams published today (November 5) in Science.
Cancer immunotherapies that block immune inhibitory pathways are now available as treatments for several tumor types, yet patients’ responses to these therapies vary. Aside from the presence of T cells within the tumor before the start of treatment, it has not been clear what other factors are linked to a response to these antibodies. The two studies published today, while not the first to suggest thatgut microbes can influence the efficacy of cancer therapy, provide a definitive link between gut microbiome composition and cancer immunotherapy response and implicate the positive role of specific bacterial species.
“These interesting papers combine two of the hottest areas in science—the microbiome and immunology—showing that gut bacteria can activate [host] anti-tumor responses,” said Timothy Hand of the department of immunology at the University of Pittsburgh who was not involved in either study.
M. Vétizou et al., “Anticancer immunotherapy by CTLA-4 blockade relies on the gut microbiota,” Science, doi:10.1126/aad1329, 2015.
A. Sivan et al., “Commensal Bifidobacterium promotes antitumor immunity and facilitates anti–PD-L1 efficacy,” Science, doi:0.1126/science.aac4255, 2015.