CEACAM5 and colorectal carcinoma: We then investigated the CEA glycosylation of CRC patients with different progression, which contained three in stage II (CEA below 2 ng/ml), three in stage III (two with CEA around 3 ng/ml and one with CEA 300 ng/ml), and five in stage IV (CEA above 250 ng/ml) (Fig. 6A, Supplemental Table S1).