MUC5AC and colorectal carcinoma: Analysis of CRC subtypes, using the consensus molecular subgroup (CMS) classification from Guinney et al., 2015, indicated a radically different distribution of high and low MUC5AC-expressing tumours among subtypes: CMS1 (28% vs. 10%), CMS2 (15% vs. 41%), CMS3 (36% vs. 6%), and CMS4 (5% vs. 26%) (Figure 1E).