(PQ5) Mitochondrial Heterogeneity in Melanoma Tumor and Immune Responses

项目总结 这一建议直接回应了RFA-CA-17-017PQ5：线粒体异质性是如何 影响肿瘤的发生或发展？肿瘤的发生、生长、死亡和转移与 以线粒体为中心的细胞代谢和信号的显著变化。线粒体 是调节能量代谢、信号传递和细胞凋亡的复杂细胞器，含有线粒体 DNA(线粒体DNA)，从内部连接呼吸和ATP产生。人们往往低估了 不同细胞类型的线粒体，甚至同一类型的单个细胞内的线粒体，在功能和 动力(位置、形状和运动)基本和对压力的反应。目前尚不清楚 线粒体异质性的这些方面是如何促进肿瘤发生的。发生了惊人的变化 肿瘤中存在葡萄糖代谢和线粒体呼吸(“Warburg效应”)；然而，这些 代谢适应既不是一成不变的，也不是一成不变的。例如，线粒体和肿瘤的代谢 细胞，渗透免疫细胞和基质细胞，是多样的，并对不断变化的环境做出反应 压力，包括营养和氧气供应、酸碱度和生长因子的变化。最重要的是 这项提议的主题是线粒体呼吸、网络动力学和 线粒体DNA-干扰素信号转导系统不仅影响癌细胞的新陈代谢和生长，而且还影响肿瘤细胞的生长。 他们对免疫反应和免疫治疗的敏感性。在Aim 1中，独特的小鼠黑色素瘤细胞系 将使用在免疫原性和线粒体方面表现出显著差异的 呼吸和线粒体DNA水平。在这些细胞中，线粒体呼吸将通过以下途径激活或抑制 分别敲除MCJ或Cox10基因与肿瘤生长、免疫反应性和对 抗PD1检查点阻断(免疫疗法)将解决直接检查线粒体如何 异质性与免疫原性/免疫逃避有关。线粒体动力学中的异质性和 新陈代谢也将直接使用微流控、单细胞方法进行评估。最后，作为一种潜在的 增强抗肿瘤免疫的治疗途径，T细胞将被改造成增加线粒体 呼吸和三磷酸腺苷的产生。在目标2中，重点将放在mtdna应激介导的干扰素信号的作用上。 以及它是否导致了肿瘤生长、免疫反应和对免疫治疗的敏感性的差异。在……里面 目的3，患者来源的异种移植物与其肿瘤浸润性淋巴细胞配对的模型(PDX-TIL模型) 将被分析以探索线粒体呼吸的异质性与mtDNA应激的相关性 在人类癌症中发出信号。这项工作有可能阐明新的候选途径在肿瘤和 免疫细胞，以增强抗癌治疗，刺激抗肿瘤免疫。

PROJECT SUMMARY This proposal directly responds to RFA-CA-17-017 PQ5: How does mitochondrial heterogeneity influence tumorigenesis or progression? Tumor initiation, growth, death and metastasis are associated with significant changes in cell metabolism and signaling, central to which are mitochondria. Mitochondria are complex organelles that regulate energy metabolism, signaling and apoptosis, and contain mitochondrial DNA (mtDNA) that hardwires respiration and ATP production from within. It is often underappreciated that mitochondria in different cell types, and even within individual cells of the same type, vary in function and dynamics (location, shape and movement) basally and in response to stress. It is presently unclear how these aspects of mitochondrial heterogeneity contribute to tumorigenesis. Striking changes in glucose metabolism and mitochondrial respiration occur in tumors (the “Warburg effect”); however, these metabolic adaptations are neither uniform nor static. For example, mitochondria and metabolism of tumor cells, infiltrating immune cells and stromal cells, are diverse and responsive to ever-changing environmental stresses, including alterations in nutrient and oxygen availability, pH, and growth factors. The overarching theme of this proposal is that the heterogeneity in mitochondrial respiration, network dynamics and mtDNA-interferon (IFN) signaling not only affects cancer cell metabolism and growth, but also impacts their sensitivity to immune responses and immunotherapy. In Aim 1, unique mouse melanoma cell lines will be employed that exhibit significant differences in immunogenicity as well as mitochondrial respiration and mtDNA levels. In these cells, mitochondrial respiration will be activated or inhibited via knock-out of the Mcj or Cox10 genes, respectively, and tumor growth, immunoreactivity, and responses to anti-PD1 checkpoint blockade (immunotherapy) will be addressed to directly examine how mitochondrial heterogeneity links with immunogenicity/immunoevasion. Heterogeneity in mitochondrial dynamics and metabolism will also be assessed directly using microfluidic, single-cell approaches. Finally, as a potential therapeutic avenue to enhance anti-tumor immunity, T cells will be engineered to increase mitochondrial respiration and ATP production. In Aim 2, the focus will be on the role of mtDNA-stress mediated IFN signaling and whether it underlies differences in tumor growth, immune responses and sensitivity to immunotherapy. In Aim 3, models that pair patient-derived xenografts with their tumor infiltrating lymphocytes (PDX-TIL models) will be analyzed to probe the relevance of heterogeneity in mitochondrial respiration and mtDNA-stress signaling in human cancer. This work has the potential to illuminate new candidate pathways in tumor and immune cells to enhance anti-cancer therapies and stimulate anti-tumor immunity.