First Author | Islam MS | Year | 2016 |
Journal | Br J Pharmacol | Volume | 173 |
Issue | 16 | Pages | 2532-42 |
PubMed ID | 27300306 | Mgi Jnum | J:253362 |
Mgi Id | MGI:6109119 | Doi | 10.1111/bph.13535 |
Citation | Islam MS, et al. (2016) Epidermal growth factor is a critical regulator of the cytokine IL-33 in intestinal epithelial cells. Br J Pharmacol 173(16):2532-42 |
abstractText | BACKGROUND AND PURPOSE: IL-33 is a novel cytokine that is believed to be involved in inflammation and carcinogenesis. However, its source, its production and its secretion process remain unclear. Recently, we have reported that IL-33 is up-regulated in dextran sulfate sodium (DSS) colitis in mice. EXPERIMENTAL APPROACH: Production of IL-33 from intestinal tissue was studied in a murine cancer model induced by azoxymethane (AOM) and DSS in vivo and in cultures of IEC-6 epithelial cells. Cytokine levels were measured by real time PCR, immunohistochemistry and elisa. KEY RESULTS: Mice with AOM/DSS-induced colitis expressed all the characteristic symptoms of colon cancer pathology. Immunohistochemical analysis demonstrated epithelial cell-derived IL-33 in colon tissues from mice with AOM/DSS colitis. Real time PCR and quantitative PCR analysis revealed that AOM/DSS colitis tissues expressed up-regulated IL-1beta, IL-33, TGF-beta, and EGF mRNA. Gefitinib, an EGFR inhibitor, inhibited IL-33 mRNA expression in AOM/DSS colitis mice. The pathophysiological role of IL-33 in the rat intestinal epithelial cell line (IEC-6 cells) was then investigated. We found that EGF, but not TGF-beta1 or PDGF, greatly enhanced mRNA expression of IL-33 and its receptor ST2. In accordance with the gene expression and immunohistochemical analysis of IL-33 levels, elisa-based analysis of cytoplasmic and nuclear extracts showed increased IL-33 protein levels in IEC-6 cells after treatment with EGF. CONCLUSIONS AND IMPLICATIONS: Our results suggest that EGF is a key growth factor that increased IL-33 production and ST2 receptor expression during intestinal inflammation and carcinogenesis. The EGF/IL-33/ST2 axis represents a novel therapeutic target in colon cancer. |