Figure 1. Dysbiosis in Il10^−/− mice is driven by inflammation rather than cancer. WT and Il10^−/− mice were transferred from germ-free to specific pathogen free (SPF) conditions. In SPF conditions, WT mice remain healthy, but 100% of Il10^−/− mice develop colitis. Half of each cohort was treated with AOM, which induces no cancer in WT mice but cancer in ~60–80% of Il10^−/− mice. When the microbiota of each cohort was assessed by Illumina sequencing of 16S ribosomal genes, we found it did not differ by cancer status (Il10^−/− vs. AOM/Il10^−/−). In contrast, inflammatory status (Il10^−/− vs. WT) was associated with alterations in microbial community composition, including an expansion of Enterobacteriaceae bacteria.