(A) Kras PDECs treated with vehicle control (DMSO) or an NF-κB inhibitor (JSH-23) were plated for the senescence assay. Scale bars: 100 μm. Representative images are shown. (B) Conditioned media were collected from PDECs treated with DMSO or JSH-23 for cytokine array analysis. The boxed regions on the representative blot indicate the differentially secreted cytokines. (C) Quantitative analysis of B, representing the average of the pixel intensity of 2 independent experiments. Mean ± SD; *P < 0.05, **P < 0.005, ***P < 0.0005 by unpaired t test. (D) Quantification of SA-β-Gal staining in Kras PDECs treated with DMSO or 100 ng/ml CXCL1. Ratio of SA-β-Gal–positive Kras PDEC cultures to the total number of Kras PDECs was counted per ×100 optical high-power field (HPF). Mean ± SD; ***P < 0.0005 by unpaired t test. (E) Representative photomicrographs showing in situ Cxcl1 mRNA in ductal lesions (black arrowhead), in acinar cells (white arrowhead), and in immune cells (black arrow). Scale bars: 50 μm. (F) Representative SA-β-Gal staining. Scale bars: 100 μm. (G) Ratio of SA-β-Gal–positive cells to the total number of mPanIN cells in 18-week-old Kras RelA (5 mice) and Kras RelA IL-8tg (4 mice) was counted per ×200 optical field (HPF). Mean ± SD; n ≥ 28; ***P < 0.0001 by Mann-Whitney test; n, number of HPF. (H) Representative H&E staining. Scale bars: 100 μm. (I) Numbers of mPanINs were counted per ×200 optical HPF. Mean ± SD; n ≥ 3; *P < 0.05 by unpaired t test; N.D., not detectable; n, number of mice. (J) Representative immunohistological analysis for p53 and 2′,7′-dichlorofluorescein diacetate (DCFDA) from Kras RelA (n = 3) and Kras RelA IL-8tg (n = 3) mice. Scale bars: 50 μm. Quantification of p53 positivity shown at the right. Mean ± SD; *P < 0.05 by unpaired t test; n, number of mice.