164S rDNA seq of bacteria in CRC tissue
The sequence reads were analysed by the Quantitative Insights into Microbial Ecology (QIIME, http://www.qiime.org) analysis pipeline as described (Caporaso et al., 2010). Raw reads were filtered to remove the adapters and low-quality and ambiguous bases. The tags were clustered into operational taxonomic units (OTUs) with a cut-off value of 245%, and an OTU abundance statistics table of each sample was created. Finally, microbial diversity and differential bacteria were calculated by QIIME.