Inhibitors of Epithelial TGFB signaling and EMT/Sheppard

项目总结（见说明）： TGFB 1信号传导在特发性肺纤维化（IPF）的病理生物学中是突出的，但在对正常稳态重要的许多生理过程中也是关键的。针对TGFB 1信号传导衰减的抗纤维化药物可以预期毒性较小，但如果集中于纤维化特异性信号传导的方面，则仍然有效。迄今为止，在患者中实现这一目标的方法仍然难以捉摸。近年来对上皮间质转化（EMT）的研究表明，EMT在实验性肺纤维化过程中在体内发生，并在纤维化过程中起重要作用。发现EMT关键依赖于酪氨酸磷酸化（pY 654）B-连环蛋白和pSmad 2的转录复合物的整合素α 3B 1依赖性产生。这些转录复合物存在于IPF肺的提取物中，并定位于这种疾病中积累的肌成纤维细胞的细胞核，这意味着TGFB 1信号传导的相对特异性途径可通过新的治疗方法实现。本申请的目标是开发新的试剂， EMT和肺纤维化在小鼠体内的研究，可以作为该项目临床阶段药物开发的基础。最近鉴定的阻断pY 654-β-连环蛋白生成的整联蛋白α 3B 1衍生肽和促进BY-B-连环蛋白周转的小分子将是抑制剂优化和在鼠肺纤维化模型中测试的起点。这两种抑制剂类都离体阻断EMT。此外，模拟整联蛋白衍生肽和/或离体阻断EMT的小分子的基于细胞的高通量筛选将用于开发用于优化和体内测试的另外的先导化合物。该项目将与肽和小分子优化的药物化学核心密切合作，与人体组织核心密切合作，以研究具有原代人肺泡上皮细胞的有前途的先导化合物，与纵向队列核心密切合作，以表征机械信息生物标志物，并与项目2密切合作，开发用于药物递送的气雾剂系统。我们预计，拟议的研究应既检验抑制EMT是减弱纤维化的有效方法的原则，又为进一步开发IPF治疗药物提供有前景的候选药物。

PROJECT SUMMARY (See instructions): TGFB1 signaling is prominent in the pathobiology of idiopathic pulmonary fibrosis (IPF) but is also critical in many physiological processes important to normal homeostasis. Anti-fibrotic drugs directed at attenuation of TGFB1 signaling could be expected to be less toxic and yet still effective if focused on aspects of signaling specific to fibrogenesis. An approach to achieve this goal in patients has to date remained elusive. Recent studies of epithelial mesenchymal transition (EMT) indicate EMT develops in vivo during experimental lung fibrosis and is important to the fibrotic process. EMT was found to critically depend on integrin a3B1-dependent generation of transcriptional complexes of a tyrosine phosphorylated (pY654) B-catenin and pSmad2. These transcriptional complexes are present in extracts of IPF lungs and localize to nuclei of accumulating myofibroblasts in this disorder, implying a relatively specific pathway of TGFB1 signaling approachable by novel therapeutics. The goal of this application is to develop new reagents that attenuate EMT and pulmonary fibrosis in vivo in mice that could be the basis for drug development in the clinical phase of the project. Recently identified integrin a3B1-derived peptides that block pY654-P-catenin generation and small molecules that promote turnover of BY-B-catenin will be the starting points for inhibitor optimization and testing in models of murine lung fibrosis. Both of these inhibitor classes block EMT ex vivo. In addition a high throughput cell based screen of small molecules that mimic the integrin-derived peptides and/or block EMT ex vivo will be used to develop additional lead compounds for optimization and in vivo testing. The project will work closely with the medicinal chemistry core for peptide and small molecule optimization, with the human tissue core to examine promising lead compounds with primary human alveolar epithelial cells, with the Longitudinal Cohort Core to charactize mechanistically informative biomarkers, and with Project 2 that will develop an aerosol system for drug delivery. We anticipate that the proposed studies should both test the principle that inhibition of EMT is an effective approach to attenuation of fibrogenesis and provide promising candidates for futher development as therapeutics for IPF.