Factor 1

Pancreases were harvested from 8-week-old mice and flash frozen in liquid N₂ immediately upon dissection. Frozen tissue was lysed in Bio-Plex Lysis Buffer (Bio-Rad, #171304011) supplemented with Factor I (Bio-Rad, #171304011), Factor II (Bio-Rad, #171304011), and cOmplete protease inhibitor cocktail (Sigma-Aldrich) according to the manufacturer’s instructions. Lysates were clarified by centrifugation and immunoblotting was performed as previously described.^{55 (link)} The following primary antibodies were employed in this study: DCLK1 (Cell Signaling, #62257) and GAPDH (Cell Signaling, #D16H11). Immunoglobulin G horseradish peroxidase linked secondary antibodies were employed as appropriate.
Animal studies for immunohistochemistry and immunoblotting (Supplementary Fig. 8a–b) were approved and performed in accordance with the IACUC at Beth Israel Deaconess Medical Center. All experiments were adherent to institutional standards and were performed in pathogen-free animal facilities. Pdx1-Cre mice were obtained from The Jackson Laboratory (#014647); K-Ras^LSL-G12D (#01XJ6) and Tp53^LSL-R172H (#01XM2) mice were obtained from the NCI Mouse Repository.