Abstract
AbstractChanges in the abundance of certain bacterial species within the colorectal microbiota correlate with colorectal cancer development. While carcinogenic mechanisms of single pathogenic bacteria have been characterizedin vitro, limited tools are available to investigate interactions between pathogenic bacteria and both commensal microbiota and colonocytes in a physiologically relevant tumor microenvironment. To address this, we developed a microfluidic device that can be used to co-culture colonocytes and colorectal microbiota. The device was used to explore the effect ofFusobacterium nucleatum, an opportunistic pathogen associated with colorectal cancer development in humans, on colonocyte gene expression and microbiota composition.F. nucleatumaltered the transcription of genes involved in cytokine production, epithelial-to-mesenchymal transition, and proliferation in colonocytes in a contact-independent manner; however, most of these effects were diminished by the presence of fecal microbiota. Interestingly,F. nucleatumsignificantly altered the abundance of multiple bacterial clades associated with mucosal immune responses and cancer development in the colon. Our results highlight the importance of evaluating the potential carcinogenic activity of pathogens in the context of a commensal microbiota, and the potential to discover novel inter-species microbial interactions in the colorectal cancer microenvironment.
Publisher
Cold Spring Harbor Laboratory