MUC5AC and colorectal adenoma: For example, Byrd and Bresalier found that the expression of mucin 1 (MUC1) is increased in colon cancers and that of mucins 5AC (MUC5AC) is frequently present in colorectal adenomas and colon cancers [52] (Table 4), indicating that the enrichment of A. muciniphila in tumor microenvironment may result from the increased substrate concentration (Figure 2b).