Ductal deletion of Hnf1b leads to enhanced signaling pathways that favor tumorigenesis. (A) RT-qPCR of YAP transcriptional targets. (B–E) CTGF (brown) immunohistochemistry. A strong ectopic CTGF staining was observed in (C’) acinar cells in mutants in (D’) the epithelium of metaplastic ducts and (E’) in PanIN. (F) RT-qPCR of the Notch pathway. (G and H) HEY2 immunohistochemistry. (I) RT-qPCR of TGF-β1. (J and K) Phospho-SMAD2 (Ser465, Ser467) immunohistochemistry. (L) RT-qPCR of EGFR. (M and N) Phospho-AKT (Ser473) immunohistochemistry. Nuclei were counterstained with hematoxylin. Scale bars: 100 μm. Control, n ≥ 3; mutant, n ≥ 3 for immunohistochemistry; and control, n = 6; mutant, n = 5 for RT-qPCR. *P < .05; **P < .01; ***P < .001.