Cell-based, small molecule screens for novel radioprotective agents

细胞暴露于电离辐射(IR)可激活一系列分子信号通路，导致细胞周期停滞、DMA修复和/或细胞凋亡。每条信号通路都有一个特有的分子信号，由激活的(磷酸化的)目标蛋白和辐射诱导的核灶中的蛋白质组装来定义。这些方便的分子标记(生物标记物)现在可以用于开发人类辐射暴露的诊断和治疗医学应用程序。在具体目标1中，我们将检查一个辐射损伤反应途径(范可尼贫血途径)中的生物标志物，以产生、测试和校准小鼠和人类模型中的生物剂量计。我们会采集外周血 为了测试生物剂量计的敏感性和特异性，对接受全身照射的癌症患者的淋巴细胞进行了检测。在具体目标2中，我们将进行途径特异性和一般细胞为基础的小分子药物筛选，以确定新的辐射防护剂。这些试剂将在小鼠和骨髓祖细胞检测中测试其细胞保护作用。在具体目标3中，我们将分析一种新型的活性氧(ROS)清除剂WW-85，用于小鼠和人类的辐射防护测试。我们将在小鼠辐射LD50模型中测试WW-85提高存活率的能力，减轻辐射诱导的组织损伤，并提高小鼠骨髓干细胞的克隆性存活。这项工作将通过与其他项目(利文斯顿、埃利奇、西辛斯基)以及与小鼠生物学和干细胞核心(核心B)、化学和化学筛选研究所核心(核心C)以及放射临床试验核心的大量互动来加强。

Cellular exposure to ionizing radiation (IR) activates a series of molecular signaling pathways, leading to cell cycle arrest, DMA repair, and/or apoptosis. Each signaling pathway has a characteristic molecular signature, defined by activated (phosphorylated) target proteins, and protein assembly in radiation-inducible nuclear foci. These convenient molecular signatures (biomarkers) can now be exploited in the development of diagnostic and therapeutic medical applications for human radiation exposure. In specific Aim 1, we will examine biomarkers in one radiation damage-response pathway (the Fanconi Anemia Pathway), to generate, test, and calibrate a biodosimeter in mouse and human models. We will obtain peripheral blood lymphocytes from human cancer patients undergoing Total Body Irradiation in order to test the sensitivity and specificity of the biodosimeter. In Specific Aim 2, we will conduct pathway-specific and general cell-based, small molecule drug screens, in order to identify novel radioprotective agents. Agents will be tested in murine and bone marrow progenitor assays for their cytoprotective effect. In specific aim 3, we will analyze a novel Reactive Oxygen Species (ROS) scavenger, WW-85, in murine and human radiation protection assays. We will test the ability of WW-85 to improve survival in the murine radiation LD50 model, lessen radiation-induced tissue damage, and improve the clonigenic survival of murine bone marrow stem cells. The work will be fortified by numerous interactions with the other projects (Livingston, Elledge, Sicinski) and with the Mouse Biology and Stem Cell Core (Core B), the Institute for Chemistry and Chemical Screening Core (Core C), and the Radiation Clinical Trial Core.