CANCER BIOLOGY: Edited by Pierre Hainaut and Amelie PlymothProbiotics-mediated suppression of cancerSo, Stephanie S.Y.a; Wan, Murphy L.Y.a; El-Nezami, Hania,bAuthor Information aSchool of Biological Sciences, Faculty of Science, Kadoorie Biological Sciences Building, The University of Hong Kong, Pokfulam, Hong Kong bInstitute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland Correspondence to Hani El-Nezami, 5S-13, School of Biological Sciences, Faculty of Science, Kadoorie Biological Sciences Building, The University of Hong Kong, Pokfulam Road, Hong Kong. Tel: +852 2299 0835; fax: +852 2299 0364; e-mail: [email protected] Current Opinion in Oncology: January 2017 - Volume 29 - Issue 1 - p 62-72 doi: 10.1097/CCO.0000000000000342 Buy Metrics Abstract Purpose of review Probiotics can be used as an adjuvant for cancer prevention or/and treatment through their abilities to modulate intestinal microbiota and host immune response. Although most of the recent reviews have focused on the potential role of probiotics against colon cancer, only few of them include the probiotic effect on extraintestinal cancers. The present review covers the most important findings from the literature published during the past 20 months (from January 2015 to August 2016) regarding the probiotics-mediated suppression of both gastrointestinal and extraintestinal cancers and the underlying mechanisms. Recent findings A comprehensive literature search in Pubmed, Science direct and Google scholar databases was conducted to locate all relevant articles that investigated the effect of probiotics on prevention/treatment of both gastrointestinal and extraintestinal cancers. Different mechanisms for the beneficial effects of probiotics against cancer were also discussed, mainly via modulation of gut microbiota which thereby influences host metabolism and immunity. Summary Despite laboratory-based studies having demonstrated encouraging outcomes that probiotics possess antitumor effects, the benefits should not be exaggerated before we get more results from human clinical trials. These are very important before the medical community can accept the use of probiotics as an alternative therapy for cancer control. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.