Pancreata from KrasG12D-Prdm3ΔAcinar mice had full spectrum of precursor lesions including low-grade PanINs, high-grade PanINs and ductal carcinoma in situ (Supplementary Fig. 3a), which had lost Prdm3 staining (Supplementary Fig. 3b). This evidence concerns the gene MECOM and ductal breast carcinoma in situ.