MUC5AC and pancreatic intraductal papillary-mucinous neoplasm: Immunohistochemical analysis of mucins (MUC) revealed that IPMN lesions from KPPS mice exhibited high expression of MUC1, weak expression of MUC5AC, and minimal to no expression of MUC2 (Figure 1E and Figure S1C), suggesting a non‐intestinal IPMN subtype (including gastric and pancreatobiliary types).