IL-1 Receptor Antagonist Inhibits Pancreatic Cancer Growth by Abrogating NF-κB Activation

Purpose: Constitutive NF-κB activation is identified in about 70% of pancreatic ductal adenocarcinoma (PDAC) cases and is required for oncogenic KRAS-induced PDAC development in mouse models. We sought to determine whether targeting IL-1α pathway would inhibit NF-κB activity and thus suppress PDAC cell growth. Experimental Design: We determined whether anakinra, a human IL-1 receptor (rhIL-1R) antagonist, inhibited NF-κB activation. Assays for cell proliferation, migration, and invasion were performed with rhIL-1R antagonist using the human PDAC cell lines AsPc1, Colo357, MiaPaCa-2, and HPNE/K-rasG12V/p16sh. In vivo NF-κB activation–dependent tumorigenesis was assayed using an orthotopic nude mouse model (n = 20, 5 per group) treated with a combination of gemcitabine and rhIL-1RA. Results: rhIL-1R antagonist treatment led to a significant decrease in NF-κB activity. PDAC cells treated with rhIL-1R antagonist plus gemcitabine reduced proliferation, migration, and invasion as compared with single gemcitabine treatment. In nude mice, rhIL-1R antagonist plus gemcitabine significantly reduced the tumor burden (gemcitabine plus rhIL-1RA vs. control, P = 0.014). Conclusions: We found that anakinra, an FDA-approved drug that inhibits IL-1 receptor (IL-1R), when given with or without gemcitabine, can reduce tumor growth by inhibiting IL1α-induced NF-κB activity; this result suggests that it is a useful therapeutic approach for PDAC. Clin Cancer Res; 22(6); 1432–44. ©2015 AACR.