As studies on mucins have developed, the gastric and intestinal phenotypes of gastric adenocarcinoma have been clearly revealed by the expression of different epithelial differentiation markers (MUC5AC and MUC6 as markers for the gastric phenotype, and MUC2 and CD10 as markers for the intestinal phenotype).13, 14. This evidence concerns the gene MUC5AC and gastric adenocarcinoma.