MUC2 and colorectal carcinoma: Moreover, based on evidences showing that the mucus layer attenuates the cytotoxic activity of the E. coli phylotype B2 in vitro48, it is possible to speculate that the lower level of MUC2 in Pirc rats may expose their epithelium to potentially cytotoxic bacterial strains48, an hypothesis that should be verified in vivo, labelling with probes recognizing those specific bacteria the colon mucosa of both wt and Pirc rats5, as well of clinical specimens from patients at various CRC risk.