The Microbiota: A New Player in the Etiology of Colorectal Cancer
Colorectal cancer is one of the commonest forms of cancer worldwide. Although the molecular pathogenesis of colorectal cancer shares many characteristics with that of other cancers, the tissue environment is unique in that the intestinal mucosal surface is continuously exposed to a vast community of microorganisms. It is increasingly recognized that the intestinal microbiota is a critical component of the tumor environment that contributes to the development of colorectal cancer, and certain members of the commensal microbiota have been identified as critical elements in intestinal carcinogenesis. As sensors of the presence of microbes at mucosal surfaces, pattern-recognition receptors of the innate immune system are equally involved in this process. This review summarizes our current knowledge of the role of the microbiota in colorectal cancer development and provides an overview of the mechanisms involved in the cross talk between intestinal microbial colonization and tumorigenesis.
KeywordsColon cancer Microbiota Dysbiosis Inflammation Therapy
We thank the members of the Elinav laboratory for fruitful discussions. We apologize to authors whose relevant work was not included in this review owing to space constraints. Eran Elinav is supported by grants provided by the Abisch-Frenkel Foundation, the Kenneth Rainin Foundation, the Leona M. and Harry B. Helmsley Charitable Trust, the Israel Science Foundation, and the German-Israel Foundation, and a Marie Curie Career Integration Grant Christoph Thaiss is funded by a Boehringer Ingelheim Fonds PhD Fellowship. We thank A. Levy and Z. Levy for excellent support.
Compliance with Ethics Guidelines
Conflict of Interest
Maayan Levy, Christoph A. Thaiss, and Eran Elinav declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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