Gut bacteria may aid anti-cancer treatment

Dr Mutsa Madonda completed his PhD with Prof Magdalena
Plebanski and is now a post doc in her lab.

by Anne Crawford

Monash University researchers are part of an international collaboration that has identified two intestinal bacteria as being potentially important in the effectiveness of anti-cancer medication.

The researchers found that the compound Cyclophosphamide (CTX), used in chemotherapy, relies on Enterococcus hirae and Barnesiella intestinihominis for its efficacy in countering tumours.

Their study, published in the journal Immunity, shows that the two gut bacteria changed the tumour microenvironment, activating T cells and helping the body fight cancer cells. More specifically, they reduced regulatory T cells and stimulated anti-tumour Cytotoxic T lymphocytes (CTL) responses.


Importantly, the scientists – including Professor Magdalena Plebanski, head of Monash University’s Vaccine and Infectious Diseases Laboratory, and post-doctoral researcher Dr Mutsa Madondo – found that immune responses triggered by the bacteria were associated with survival in advanced lung and ovarian cancer patients resistant to chemotherapy.

The findings may help in the development of oncomicrobiotics that will optimise cancer therapies in the future.

They are an exciting development in the emerging field of ‘‘oncomicrobiotics’’, which investigates how gut microorganisms could improve the effectiveness of cancer therapies. The precise identification of bacteria capable of linking intestinal and anti-cancer immune responses is key to this.

Whilst research linking the gut microbiome to the emergence of inflammatory disorders has come of age, the bacterial species involved in tumour immunosurveillance and their mechanism of action is largely unclear and unappreciated, the study says. More oncomicrobiotics are likely to be unravelled in the near future, its authors predict.

Reference
Daillère R, Vétizou M, Waldschmitt N, Yamazaki T, Isnard C, Poirier-Colame V, Duong CP, Flament C, Lepage P, Roberti MP, Routy B, Jacquelot N, Apetoh L, Becharef S, Rusakiewicz S, Langella P, Sokol H, Kroemer G, Enot D, Roux A, Eggermont A, Tartour E, Johannes L, Woerther PL, Chachaty E, Soria JC, Golden E, Formenti S, Plebanski M, Madondo M, Rosenstiel P, Raoult D, Cattoir V, Boneca IG, Chamaillard M, Zitvogel L. Enterococcus hirae and Barnesiella intestinihominis Facilitate Cyclophosphamide-Induced Therapeutic Immunomodulatory Effects. Immunity. 2016 Oct 18;45(4):931-943. doi: 10.1016/j.immuni.2016.09.009. Epub 2016 Oct 4.

See also Catharine Paddock's summary for Medical News Today, "Gut bacteria boost effectiveness of common chemotherapy drug", 6 October 2016. Link