Many studies explored the microbial community of CRC samples in different cohorts, and established the associations of F. nucleatum with important clinical and molecular features.53,57–63 For instance, F. nucleatum was shown to be significantly associated with MLH1 methylation,53,57,59,60,63 high-level MSI,53,57,59–63 high-level CIMP53,59,60,63 and BRAF mutation57,59,61,62 (Table 1). Here, MLH1 is linked to colorectal carcinoma.