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Bacterial oncogenesis in the colon

    Christine Dejea

    Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA

    ,
    Elizabeth Wick

    Department of Surgery, Johns Hopkins University School of Medicine, 733 N Broadway, Baltimore, MD 21205, USA

    &
    Cynthia L Sears

    * Author for correspondence

    Department of Medicine, Johns Hopkins University School of Medicine, 733 N Broadway, Baltimore, MD 21205, USA. .

    Department of Oncology, Johns Hopkins University School of Medicine, 733 N Broadway, Baltimore, MD 21205, USA

    Sidney Kimmel Comprehensive Cancer Center, 401 N Broadway, Baltimore, MD 21287, USA

    Published Online:https://doi.org/10.2217/fmb.13.17

    The human colon plays host to a diverse and metabolically complex community of microorganisms. While the colonic microbiome has been suggested to contribute to the development of colorectal cancer (CRC), a definitive link has not been made. The role in which the colon microflora could contribute to the initiation and/or progression of CRC is explored in this review. Potential mechanisms of bacterial oncogenesis are presented, along with lines of evidence derived from animal models of microbially induced CRC. Particular focus is given to the oncogenic capabilities of enterotoxigenic Bacteroides fragilis. Recent progress in defining the microbiome of CRC in the human population is evaluated, and the future challenges of linking specific etiologic agents to CRC are emphasized.

    Papers of special note have been highlighted as: ▪ of interest

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