In the adult mouse pancreas, ADM may be triggered by inflammation and other factors. Known associations with ADM include, but are not limited to, extracellular cues — TGF-α, Hedgehog signaling, Notch signaling — and intracellular alterations mediated by Kras^G12D activation, including induction of Pdx1, induction of TNF-α, and decreased Mist1 expression. Ductal cells or duct-like cells are replaced by healthy acinar cells during recovery from injury. ADM might represent a precursor lesion to PanIN and constitute a cell of origin for PanIN. The cell of origin for PanIN might be a ductal cell or a distinct yet-to-be-identified progenitor cell.