Deciphering Mechanisms of Nitrogen-Containing Bisphosphonates - Admin Supplement

摘要 据估计，55%的美国人患有骨质疏松症和骨量减少。 50岁以上；总人口超过5000万人，对患者的生活质量造成重大影响。这个 目前骨质疏松症的标准治疗方法是服用含氮双膦酸盐(NBPS)。 然而，这些高电荷药物进入、运输和到达它们的分子的机制 靶细胞和效应靶细胞知之甚少。这项提议的长期目标是解构 NBP反应所必需的分子途径。为了做到这一点，我们将建立在初步的遗传学研究的基础上，通过 使用细胞分析和小鼠模型，以及体外结合和功能分析来探索 Nbps和我们确定的目标之间的相互作用。我们之前的工作利用了两个不同的高吞吐量 全基因组筛选，以确定nbps作用所需的200多个基因。我们最初的重点是 关于ATRAID和SLC37A3两个基因对nbps的反应有很大影响的研究一直在进行。 很可能是这些药物的胞内贩运所必需的。此建议建立在此基础上，以i) 剖析ATRAID和SLC37A3如何促进NBP的运输及其细胞功能，II)调查 两个转录因子，与骨密度的变化有关，当被耗尽时，可能会使细胞对 (3)利用条件性ATRAID基因敲除小鼠，研究其作用机制。 这些药物对骨转移有治疗作用。总而言之，这些研究产生了关于 NBPS用来影响细胞和组织的分子通路。该提案侧重于已确定的 基因，并将为未来的工作奠定基础，确定在药物筛查中识别的基因如何预测 患者对nbps的反应，包括治疗效果、所需nbps剂量和不良反应。 此外，这一重点在于了解一种廉价的、常用的处方药的作用机制 为骨质疏松症治疗策略的发展带来新的视角和假设。

Abstract Osteoporosis and low bone mass (osteopenia) are estimated to affect 55 percent of the American population over the age of 50; over 50 million people in total, with major consequences for the patients’ quality of life. The current standard treatment for osteoporosis is administration of nitrogen-containing bisphosphonates (NBPs). However, the mechanism by which these highly-charged drugs enter, traffic through, and reach their molecular targets and effect target cells is poorly understood. The long-term goal of this proposal is to deconstruct the molecular pathways essential for NBP response. To do this, we will build upon preliminary genetic studies by using cell assays and mouse models, as well as in vitro binding and functional assays to explore the interactions between NBPs and our identified targets. Our previous work utilized two distinct high-throughput genome-wide screens to identify over 200 genes required for the action of NBPs. The initial focus of our studies has been on the role of two genes, ATRAID and SLC37A3, that strongly affect the response to NBPs, and are likely to be required for the endocytic trafficking of these drugs. This proposal builds upon this to i) dissect how ATRAID and SLC37A3 facilitate NBP trafficking and their cellular function, ii) investigate the role of two transcription factors, associated by GWAS with changes in BMD, that when depleted may sensitize cells to the effects of NBPs, and iii) using conditional ATRAID knockout mice, investigate the mechanism by which these drugs are therapeutic for bone metastases. Together, these studies generate a broader picture of the molecular pathways that NBPs use to affect cells and tissues. This proposal focuses on a subset of identified genes, and will set the stage for future work determining how genes identified in drug screens may predict patient response to NBPs, including efficacy of treatment, dosage of NBPs needed, and adverse side effects. Moreover, this focus on understanding the mechanisms of an inexpensive, commonly prescribed drug will bring new perspectives and hypotheses to the development of treatment strategies for osteoporosis.