Contribution of Nuclear S1P Signaling to Microtubule Targeting Agent-Induced Changes in Transcriptional Activity in Human iPS-SNs

项目概要/摘要 化疗引起的周围神经病变是一种常见的剂量限制性毒性， 有效性和影响癌症患者的生活质量。这项研究的首要目标是 确定化疗诱导的周围神经病变的分子基础，以支持 靶向治疗以预防和治疗这种毒性。拟议的研究是基于一个反向翻译 药物遗传学方法，使用遗传关联发现来暗示外周血中的关键途径。 神经病变最近的遗传关联和功能验证结果支持鞘氨醇-1- 化疗诱导的神经毒性中的磷酸盐（S1 P）信号传导，这与之前的研究一致 在啮齿动物模型中。本申请中提出的研究将扩展这些发现，并解决一个重要的问题。 我们对S1 P信号在毒性靶细胞外周感觉神经元中的知识存在空白。中央 将要检验假设是微管对外周感觉神经元中的S1 P信号传导的调节 靶向剂在其神经毒性中起关键作用。一种人诱导多能干细胞， 化疗神经毒性的感觉神经元模型（iPS-SN）将用于所有研究。 药理学和遗传学方法将用于调节S1 P信号传导和询问 化疗毒性与此信号通路有关。这三个目标相辅相成， S1 P的离散函数第一个目标是研究微管靶向剂是否改变鞘脂 在感觉神经元的代谢，并将特定的S1 P受体的细胞骨架的变化。研究 在第二个目标中提出的将集中于S1 P受体下游的Rho GT3信号传导，并且将 建立S1 P信号传导轴，该轴对于化疗诱导的神经突结构变化和 收缩球的发展。第三个目标将使用scRNA-seq和sc-ATACseq来阐明是否 紫杉醇诱导的iPS-SN中基因表达的变化涉及S1 P对染色质可及性的影响。的 芬戈莫德是一种靶向S1 P受体信号传导的多发性硬化症治疗药物，目前正在 用于预防和治疗紫杉醇引起的周围神经病变， 将检查化疗诱导的神经毒性。总的来说，这些研究将揭示分子 感觉神经元响应微管的轴突变性的潜在机制 靶向剂和阐明芬戈莫德的神经保护的新机制。

PROJECT SUMMARY/ABSTRACT Chemotherapy induced peripheral neuropathy is a common dose-limiting toxicity that can reduce therapeutic effectiveness and impact quality of life for cancer patients. The overarching goal of this research is to determine the molecular basis of chemotherapy-induced peripheral neuropathy to support the development of targeted therapies to prevent and treat this toxicity. The proposed studies are based on a reverse translational pharmacogenetic approach that uses genetic association findings to implicate critical pathways in peripheral neuropathy. Recent genetic association and functional validation findings support a role for sphingosine-1- phosphate (S1P) signaling in chemotherapy-induced neurotoxicity, which are consistent with previous studies in rodent models. The studies proposed in this application will extend these findings and address a significant gap in our knowledge of S1P signaling in target cells for toxicity, peripheral sensory neurons. The central hypothesis that will be tested is that modulation of S1P signaling in peripheral sensory neurons by microtubule targeting agents plays a critical role in their neurotoxicity. A human induced pluripotent stem cell derived sensory neuron model of chemotherapy neurotoxicity (iPS-SNs) will be employed for all studies. Pharmacological and genetic approaches will be used to modulate S1P signaling and interrogate chemotherapy toxicity linked to this signaling pathway. The three aims are complementary and address discrete functions of S1P. The first aim will investigate whether microtubule targeting agents alter sphingolipid metabolism in sensory neurons and will link specific S1P receptors to cytoskeletal changes. The studies proposed in the second aim will focus on Rho GTPase signaling downstream of S1P receptors and will establish the S1P signaling axis that is critical for chemotherapy-induced changes in neurite structure and the development of retraction bulbs. The third aim will use scRNA-seq and sc-ATACseq to elucidate whether paclitaxel-induced changes in gene expression in iPS-SNs involve S1P effects on chromatin accessibility. The ability of fingolimod, a multiple sclerosis therapy that targets S1P receptor signaling and is currently being tested for prevention and treatment of paclitaxel-induced peripheral neuropathy, to protect against chemotherapy-induced neurotoxicity will be examined. Collectively, these studies will reveal molecular mechanisms underlying the axon degeneration that occurs in sensory neurons in response to microtubule targeting agents and elucidate novel mechanisms for neuroprotection with fingolimod.