Our 2nd prize winner is:
Diya is in her final year at Imperial College School of Medicine, where she undertook a BSc in Gastroenterology and Hepatology. She has worked as an academic researcher exploring the microbiome and its role in Clostridium Difficile infection. In the future, she hopes to pursue an academic clinical career in medicine. Congratulations, Diya!
Microbiome and Cancer: a Promising Future
This decade, the thrilling evolution of novel systems biology technologies has allowed us to explore the nexus between health and disease with greater innovation and scrutiny than ever before. Through metabonomics, metabolite exploration of biofluids, and metagenomics/metataxonomics, quantifying structure and functions of bacterial communities (1), the pronounced role of our microbiome in carcinogenesis, immune-surveillance and disease is becoming highly evident. Yet its vast future role in cancer investigation and treatment remains largely uncertain, with several important questions still to be answered.
Research purporting to the importance of our gut microbiome in various diseases, including Crohn’s disease, asthma and diabetes, is widely recognised. However, we are now gaining an appreciation of the complex interplay between our microbiome, inflammation and cancer: colorectal carcinogenesis is a notable example where gut F. nucleatum, B. fragilis, S.bovis and E. coli appear to play an active role (2). Another interesting facet of our microbiome is its relationship with our bile acid composition and pool size. Disturbance to this equilibrium can lead to numerous gastrointestinal cancers: research links cirrhosis, faecal bile acid concentrations and gut microbiota composition (3); and microbiota-mediated production of deoxycholic acid is associated with hepatocellular carcinoma (4). Interestingly, recent evidence shows that our gut microbiota play a further role, to enhance tumour immune-surveillance (5). It is now being shown that even cancer therapies, including oxaliplatin and cyclophosphamide efficacy are affected by distinct microbial environments (5). This renders the question: could we manipulate our microbiome to enhance chemotherapy in the future? The ability to modify our microbiome is remarkable, notably through probiotics, diet, antibiotics and age- perhaps now we could use this knowledge to alter it as a medical adjuvant to treatment, or even as a treatment itself.
Despite acquiring the tools and the interest to develop new microbiome therapeutics, multiple questions and challenges still remain unaddressed. Unearthing the ‘good’ bacteria from the ‘bad’ is one immense challenge; it is hard to identify whether all these reported microbiome alterations are the cause or effect of carcinogenesis. Furthermore, manipulating our microbiome may have unwanted effects on other disease states or major safety implications (6). If we were to resolve these initial difficult questions, through initial honing of bacterial profiling and function, we would be one step closer to creating innovative screening tools, biomarkers and exciting therapeutics.
It is most definitely an enthralling, but challenging, time for novel system biology technologies and scientists are now beginning to fully uncover the inescapable significance of “microbiome immune-oncology” in cancer treatment and prevention.
(1) Marchesi JR, Adams DH, Fava F, Hermes GDA, Hirschfield GM, Hold G, et al. The gut microbiota and host health: a new clinical frontier. Gut. 2016;65(2):330–339.
(2) Lucas C, Barnich N, Nguyen HTT. Microbiota, Inflammation and Colorectal Cancer. International Journal of Molecular Sciences. 2017;18(6):1310.
(3) Kakiyama G, Pandak WM, Gillevet PM, Hylemon PB, Heuman DM, Daita K, et al. Modulation of the fecal bile acid profile by gut microbiota in cirrhosis. J Hepatol. 2013;58(5):949–955.
(4) Yoshimoto S, Loo TM, Atarashi K, Kanda H, Sato S, Oyadomari S, et al. Obesity-induced gut microbial metabolite promotes liver cancer through senescence secretome. Nature. 2013;499(7456): 97–101.
(5) Zitvogel L, Ayyoub M, Routy B, Kroemer G. Microbiome and Anticancer Immunosurveillance. Cell. 2016;165(2):276-287.
(6) Mimee M, Citorik RJ, Lu TK. Microbiome therapeutics – Advances and challenges. Adv Drug Deliv Rev. 2016;105(Pt A):44-54.