The human gut microbiome has an ever-increasing role in the instigation and progression of colorectal cancer (CRC). Recent investigations have focused on identifying the key causative bacterial species and the composition and structure of the microbiome as a whole that ultimately lead to tumorigenesis in the colon. Understanding the bacterial mechanisms that promote CRC provides a rich area for the development of new screening modalities and therapeutics that may improve patient outcomes. This article reviews the various mechanisms that bacteria in the gut use to induce and/or promote tumor formation, discusses the application of the microbiome in the prevention and therapy of CRC, and provides directions for future research endeavors aiming to develop a more complete understanding of this complex phenomenon.
Submitted November 3, 2020; final revision received May 6, 2021; accepted for publication May 19, 2021.
Disclosures: Dr. Knippel has disclosed having no financial interests, arrangements, affiliations, or commercial interests with the manufacturers of any products discussed in this article or their competitors. Dr. Sears has disclosed receiving grant support from Bristol Myers Squibb and Janssen.
Funding: Research reported in this publication was supported by the NIH under award number R01 CA196845, Bloomberg Philanthropies (C.L. Sears), and the Cancer Research UK’s Grand Challenge Initiative C10674/A27140 (C.L. Sears).
Disclaimer: The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Correspondence: Cynthia L. Sears, MD, Johns Hopkins University School of Medicine, 1550 Orleans Street, CRB2 Building, Suite 1M.05, Baltimore, MD 21231. Email: firstname.lastname@example.org
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