ARID1A and pancreatic intraductal papillary-mucinous neoplasm: In a pancreas-specific mutant Arid1a-driven mouse model (Ptf1a-Cre;KrasG12D;Arid1af/f), despite early development of relatively indolent cystic precursor lesions called intraductal papillary mucinous neoplasms (IPMNs), deficiency of Arid1a in mice pancreas develops aggressive PDAC in later ages with extensive parenchymal replacement by mucinous cysts resembling low-grade branched duct gastric type IPMN (LG-IPMN) in humans (59, 61), suggesting Arid1a loss accelerates PDAC formation.