Department of Internal Medicine, Washington University School of Medicine, Saint Louis, Missouri, USA.
J Clin Invest. 2010 Jun;120(6):2081-93. doi: 10.1172/JCI40676. Epub 2010 May 10.
Epithelial-mesenchymal interactions regulate normal gut epithelial homeostasis and have a putative role in inflammatory bowel disease and colon cancer pathogenesis. Epimorphin is a mesenchymal and myofibroblast protein with antiproliferative, promorphogenic effects in intestinal epithelium. We previously showed that deletion of epimorphin partially protects mice from acute colitis, associated with an increase in crypt cell proliferation. Here we explored the potential therapeutic utility of modulating epimorphin expression by examining the effects of epimorphin deletion on chronic inflammation-associated colon carcinogenesis using the azoxymethane/dextran sodium sulfate (AOM/DSS) model. We found that mice in which epimorphin expression was absent had a marked reduction in incidence and extent of colonic dysplasia. Furthermore, epimorphin deletion in myofibroblasts altered the morphology and growth of cocultured epithelial cells. Loss of epimorphin affected secretion of soluble mesenchymal regulators of the stem cell niche such as Chordin. Importantly, IL-6 secretion from LPS-treated epimorphin-deficient myofibroblasts was completely inhibited, and stromal IL-6 expression was reduced in vivo. Taken together, these data show that epimorphin deletion inhibits chronic inflammation-associated colon carcinogenesis in mice, likely as a result of increased epithelial repair, decreased myofibroblast IL-6 secretion, and diminished IL-6-induced inflammation. Furthermore, we believe that modulation of epimorphin expression may have therapeutic benefits in appropriate clinical settings.
上皮-间充质相互作用调节正常肠道上皮稳态,在炎症性肠病和结肠癌发病机制中具有潜在作用。表皮蛋白是一种间充质和成纤维细胞蛋白,对肠道上皮具有抗增殖、促形态发生的作用。我们之前的研究表明,表皮蛋白的缺失部分保护了小鼠免受急性结肠炎的影响,与隐窝细胞增殖增加有关。在这里,我们通过研究表皮蛋白缺失对 AOM/DSS 模型中慢性炎症相关结肠癌发生的影响,探索了调节表皮蛋白表达的潜在治疗用途。我们发现,表皮蛋白表达缺失的小鼠结肠发育不良的发生率和严重程度明显降低。此外,成纤维细胞中表皮蛋白的缺失改变了共培养上皮细胞的形态和生长。表皮蛋白缺失影响了干细胞龛中可溶性间充质调节因子的分泌,如 Chordin。重要的是,LPS 处理的表皮蛋白缺陷型成纤维细胞中 IL-6 的分泌被完全抑制,体内基质 IL-6 的表达减少。总之,这些数据表明,表皮蛋白缺失抑制了小鼠慢性炎症相关的结肠癌发生,可能是由于上皮修复增加、成纤维细胞 IL-6 分泌减少以及 IL-6 诱导的炎症减轻所致。此外,我们认为调节表皮蛋白的表达可能在适当的临床环境中有治疗益处。