The cancer microbiome

Collectively known as the microbiota, the commensal bacteria and other microorganisms that colonize the epithelial surfaces of our body have been shown to produce small molecules and metabolites that have both local and systemic effects on cancer onset, progression and therapy response. To date, most studies focusing on the microbiome have used traditional preclinical mouse models and identified correlative relationships between microbial species and cancer phenotypes. Now, the profound influence of the microbiota on the efficacy of cancer treatments, such as immunotherapies, has begun to be extensively characterized in humans. Paramount to the development of microbiota-based therapeutics, the next challenge in microbiome research will be to identify individual microbial species that causally affect cancer phenotypes and unravel the underlying mechanisms. In this Viewpoint article, we asked four scientists working on the cancer microbiome for their opinions on the current state of the field, where the research is heading and how we can advance our understanding to rationally design microbial-based therapeutics to transform treatment strategies for patients with cancer. In this Viewpoint article, we asked four scientists working on the cancer microbiome to provide their opinions on the current state of the field, where the research is heading and the challenges of implementing this field for clinical utility. Eran Elinav is a professor in the Immunology Department, Weizmann Institute of Science, Israel, and the Director of the Cancer-Microbiome Division, Deutsches Krebsforschungszentrum (DKFZ), Germany. His research focuses on deciphering the molecular basis of host–microbiome interactions and their effects on health and disease, with a goal of personalizing medicine and nutrition. Wendy S. Garrett is a professor of immunology and infectious diseases at Harvard and a medical oncologist in the Gastrointestinal Cancer Center at Dana-Farber Cancer Institute. She is co-director of the Harvard Chan Center for the Microbiome in Public Health. Her laboratory seeks to carry out mechanistic microbiome studies focused on cancer, inflammatory bowel disease and immune and epithelial cell development and function. Giorgio Trinchieri is a US National Institutes of Health (NIH) Distinguished Investigator and Director of the Cancer and Inflammation Program, Center for Cancer Research (CCR), National Cancer Institute (NCI), NIH. His research has focused for many years on the interplay between inflammation, innate resistance and adaptive immunity and on the role of pro-inflammatory cytokines and interferons in the regulation of haematopoiesis, innate resistance and immunity against infections and tumours. The present focus of his laboratory is on the role of inflammation, innate resistance, immunity and the commensal microbiota in carcinogenesis, cancer progression and prevention or therapy of cancer. Jennifer Wargo is an Associate Professor of Surgical Oncology and Genomic Medicine at the University of Texas MD Anderson Cancer Center and is a co-leader of the Melanoma Moon Shot programme. Her primary interests are in response and resistance to targeted therapy for melanoma and other cancers, neoadjuvant strategies and the influence of the gut and tumour microbiome on immunity and antitumour immune responses.