Pancreatic cancer is one of the most malignant diseases in the world. Interferon regulator factor 2 (IRF-2), an interferon regulatory factor, has been known to act as an oncogene in distinct types of cancer. In this study, we found that the expression of IRF-2 was up-regulated in primary pancreatic cancer samples and associated with tumor size, differentiation, tumor–node–metastasis stage, and survival of the patients. In pancreatic cancer cells, knockdown on the expression of IRF-2 inhibited cell growth in the liquid culture and on the soft agar. Mechanistically, IRF-2 modulated the growth of pancreatic cancer cells through regulating proliferation and apoptosis effectors, such as cyclin D1 and BAX. Collectively, these results suggest that IRF-2 plays an important role in the tumorigenesis of pancreatic cancer and down-regulation of IRF-2 would be a new treatment target for pancreatic cancer.
IRF-2 Pancreatic cancer Tissue array Cell growth and apoptosis
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The authors gratefully thank the scholarship of SA-SIBS. This project is supported by China Postdoctoral Science Foundation (20100480636) to Yuezhen Deng.
Knockdown on the expression of IRF-2 did not affect cell migration. A Si con, si 1#, and si 2# MIAPaCa-2 cells were tested with the Boyden Chamber assay. After 15 h, cells that migrated through the filter membrane of the Boyden chamber were stained, and representative results are shown in the upper panel. B Quantification of migratory cells was analyzed with Image Pro software and is shown in the basal panel. (JPEG 85 kb)
Down-regulation of IRF-1 and IRF-3 in pancreatic cancer. A Relative expression of IRF-1 mRNA in 30 pancreatic cancer tissues compared to the paired normal tissues. B Relative expression of IRF-3 mRNA in 30 pancreatic cancer tissues compared to the paired normal tissues. (JPEG 37 kb)
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