Although variation in gut microbiome composition has been linked with colorectal cancer (CRC), the factors that mediate the interactions between CRC tumors and the microbiome are poorly understood. MicroRNAs (miRNAs) are known to regulate CRC progression and are associated with patient survival outcomes. In addition, recent studies suggested that host miRNAs can also regulate bacterial growth and influence the composition of the gut microbiome. Here, we investigated the association between miRNA expression and microbiome composition in human CRC tumor and normal tissues. We identified 76 miRNAs as differentially expressed (DE) in tissue from CRC tumors and normal tissue, including the known oncogenic miRNAs miR-182, miR-503, and mir-17~92 cluster. These DE miRNAs were correlated with the relative abundances of several bacterial taxa, including Firmicutes, Bacteroidetes, and Proteobacteria. Bacteria correlated with DE miRNAs were enriched with distinct predicted metabolic categories. Additionally, we found that miRNAs that correlated with CRC-associated bacteria are predicted to regulate targets that are relevant for host-microbiome interactions and highlight a possible role for miRNA-driven glycan production in the recruitment of pathogenic microbial taxa. Our work characterized a global relationship between microbial community composition and miRNA expression in human CRC tissues.
Bibliographical noteFunding Information:
C.Y. is supported by a Norman Wells Memorial Colorectal Cancer fellowship and a Healthy Foods, Healthy Lives Institute graduate and professional student research grant. This work is supported by the Randy Shaver Cancer Research and Community Fund (R.B.), an institutional research grant (124166-IRG-58-001-55-IRG53) from the American Cancer Society (R.B.), a research fellowship from the Alfred P. Sloan Foundation (R.B.), and award MNP 17.26 from the Minnesota Partnership for Biotechnology and Medical Genomics.
- Colorectal cancer
- Gene regulation
- Tumor microenvironment