Investigation of MUC5AC expression in normal-polyp-adenoma-carcinoma sequence revealed no expression of MUC5AC in normal mucosa (NM), while its staining score was higher in HP, TA with low grade dysplasia (LGD) or high grade dysplasia (HGD), mucinous carcinoma (MC), and signet ring cell carcinoma (SRCC) groups compared to NM and colorectal adenocarcinoma groups [105]. This evidence concerns the gene MUC5AC and adenoma.