Supplementary Components1. from the Dectin-1 receptor and Dectin-1 ligands within the epithelial and inflammatory compartments of PDA alongside upregulation of connected signaling intermediates. Dectin-1 ligation accelerates pancreatic oncogenesis Since Dectin-1 and its own cognate ligands are extremely indicated in PDA, we postulated that Dectin-1 signaling might promote immune-suppressive inflammation resulting in accelerated tumorigenesis. To check this, we serially treated six week-old KC mice using the Dectin-1 particular agonists depleted Zymosan (d-Zymosan) or Heat-killed Candidiasis (HKCA) and evaluated tumor development eight weeks later on in comparison to vehicle-treated pets. Ligation of Dectin-1 vigorously accelerated tumorigenesis (Figure 1fCi). Whereas pancreata in vehicle-treated KC mice harbored large areas of residually normal acinar architecture, mice treated with Dectin-1 agonists exhibited near-complete effacement of their pancreatic acini with more advanced PanIN lesions and numerous foci of invasive carcinoma embedded in Mubritinib (TAK 165) dense fibro-inflammatory stroma (Figure 1fCi). administration of Dectin-1 agonists accelerated tumor growth in orthotopically implanted KPC-derived tumors (Figure 1j). These data suggest that Dectin-1 signaling promotes PDA progression. Dectin-1 deletion is protective against PDA To determine whether Dectin-1 signaling is required for Mubritinib (TAK 165) the normal Mubritinib (TAK 165) progression of pancreatic oncogenesis, we examined the tumor-phenotype in KC;Dectin-1?/? mice over time. Dectin-1 deletion delayed malignant progression and stromal expansion. Compared with KC controls, age-matched KC;Dectin-1?/? pancreata exhibited delayed development of pancreatic dysplasia and fibrosis (Figures 2a, S3b) and extended survival (Figure 2b). To determine whether Dectin-1 deletion influences molecular oncogenesis, we probed pancreata from KC and KC;Dectin-1?/? mice for select cell cycle regulatory, oncogenic, and tumor suppressor genes. KC;Dectin-1?/? pancreata exhibited higher expression of Bcl-xL, Rb, Smad4, and p16 but reduced p53 and c-Myc expression suggesting a distinct oncogenic phenotype (Figure 2c). Collectively, these data imply that Dectin-1 contributes to the normal progression of pancreatic neoplasia in the context of a driving mutation. Open in a separate window Figure 2 Dectin-1 deletion or blockade is protective against PDA(a) KC;Dectin-1+/+ (n=10) and KC;Dectin-1?/? Rabbit Polyclonal to GPR18 (n=6) mice were sacrificed at 3, 6, or 9 months of life. Representative H&E-stained sections are shown, the percentage of pancreatic area occupied by intact acinar structures, and the fractions of ductal structures exhibiting normal morphology, acino-ductal metaplasia (ADM), or graded PanIN I-III lesions were calculated (scale bar = 200m). (b) Kaplan-Meier survival analysis was performed comparing KC;Dectin-1+/+ (n=29) and KC;Dectin-1?/? (n=41) mice (p=0.01). (c) Whole pancreas lysate from 3 month-old KC;Dectin-1+/+ and KC;Dectin-1?/? mice were assayed for expression of select oncogenic and tumor suppressor genes. (d) Six week-old KC;Dectin-1+/+ and KC;Dectin-1?/? mice were serially treated with the p-Syk inhibitor Piceatannol or vehicle for 8 weeks before sacrifice (n=5C10/group). Pancreas weights were measured and representative H&E-stained sections are shown (scale bar = 200m). Each point represents data from a single mouse. (e) WT mice bearing orthotopic PDA were serially treated with the p-Syk inhibitor Piceatannol or vehicle for 3 weeks. Tumor-infiltrating APC were harvested and tested for p-Syk expression by flow cytometry. Median fluorescence index (MFI) is shown (n=5/group; *p 0.05; **p 0.01; ***p 0.001). Syk inhibition is protective against PDA Since Dectin-1 signals via Syk phosphorylation, and we showed that Syk activation is reduced in KC;Dectin-1?/? pancreata, we postulated that Syk blockade would be protective against pancreatic oncogenesis. KC mice were treated from Mubritinib (TAK 165) 6C14 weeks of life with Piceatannol, a p-Syk inhibitor, and tested for tumor progression compared with vehicle-treated Mubritinib (TAK 165) controls. We confirmed that Piceatannol prevented Syk.