Targeting antioxidant vulnerabilities in KEAP1/NRF2 mutant NSCLC

转录因子NRF 2是细胞氧化还原平衡的中心调节因子。NRF 2突变及其阴性 在15-34%的非小细胞肺癌（NSCLC）中发现了KEAP 1调节因子。这些突变的结果是 组成性NRF 2激活和一系列NRF 2靶基因的慢性诱导，这赋予了耐药性 化疗/放疗虽然靶向NRF 2具有巨大的治疗潜力，但没有有效的策略 抑制致病性KEAP 1/NRF 2信号传导的后果。因此，至关重要的是， 了解KEAP 1/NRF 2突变型NSCLC的脆弱性，为携带KEAP 1/NRF 2突变型NSCLC的患者开发有效的治疗方法。 这些突变。NRF 2控制许多抗氧化酶的转录，从而调节抗氧化酶的活性。 活性氧的解毒。然而，在很大程度上仍然不清楚哪种特定的抗氧化剂 酶可以在治疗上靶向逆转NRF 2/KEAP 1突变对 氧化应激，化疗/放疗的关键介质。谷胱甘肽（GSH）/GSH还原酶（GSR）和 硫氧还蛋白（TXN）/硫氧还蛋白还原酶（TXNRD）是两种平行的、补偿性的巯基依赖性抗氧化剂 关键调节和维持细胞巯基氧化还原稳态和蛋白质二巯基/二硫化物的途径 平衡我的初步结果表明，GSR和TXNRD 1都是由NRF 2激活强烈诱导的 并有助于对促氧化剂疗法的内在抗性。然而，它们在不同的领域发挥着独特的作用。 细胞间室具体而言，NRF 2诱导的GSR起到保护线粒体免受氧化的作用，而 TXNRD 1保护细胞质。此外，TXNRD 1的上调与其他免疫抑制有关。 硒蛋白，表明NRF 2激活导致硒分布的不平衡。鉴于钥匙 硒蛋白在氧化还原生物学中的作用， NRF 2激活可能会产生具有治疗潜力的NRF 2活性NSCLC的新漏洞。这项建议 旨在通过定义GSR如何贡献的机制基础来进一步加强这些观察 NRF 2介导的抗氧化应激，并利用不平衡的硒蛋白翻译， 为KEAP 1/NRF 2突变型NSCLC开发有效的治疗策略。具体目标如下： 在本申请中：目标1。研究GSR在NRF 2介导的抗氧化应激中的作用。目标2. 确定NRF 2作为非小细胞肺癌硒蛋白质组调节剂的作用。知识和科学专长 我从这些拟议的研究中获得的知识将有助于我过渡到一个独立的职位。我的长期 目标是研究癌症中的抗氧化酶，主要关注硒蛋白。除了有 科学的目标，我已经概述了一个详细的职业发展计划，以获得技能，这是领导一个 研究实验室和建立强大的研究计划。我将进行拟议的研究， 在我的指导委员会的指导下制定培训计划。我将走上优秀的学术 莫菲特癌症中心提供的环境，以实现这些目标，并过渡到独立的立场。

The transcription factor NRF2 is a central regulator of cellular redox balance. Mutations in NRF2 and its negative regulator KEAP1 are found in 15-34% of non-small cell lung cancer (NSCLC). The result of these mutations is constitutive NRF2 activation and chronic induction of a battery of NRF2 target genes, which confers resistance to chemo/radiation therapy. While targeting NRF2 holds great therapeutic potential, there is no effective strategy to inhibit the consequences of pathogenic KEAP1/NRF2 signaling. It is therefore critical to identify and understand vulnerabilities of KEAP1/NRF2 mutant NSCLC to develop effective therapies for patients harboring these mutations. NRF2 controls the transcription of many antioxidant enzymes, thereby regulating the detoxification of reactive oxygen species. However, it remains largely unknown which specific antioxidant enzymes can be therapeutically targeted to reverse the profound resistance of NRF2/KEAP1 mutations to oxidative stress, the key mediator of chemo/radiation therapy. Glutathione (GSH)/GSH reductase (GSR) and thioredoxin (TXN)/thioredoxin reductase (TXNRD) are two parallel, compensating thiol-dependent antioxidant pathways that critically regulate and maintain cellular thiol redox homeostasis and protein dithiol/disulfide balance. My preliminary results indicate that both GSR and TXNRD1 are strongly induced by NRF2 activation and contribute to the intrinsic resistance to the pro-oxidant therapies. However, they play unique roles in different cellular compartments. Specifically, NRF2 induced GSR acts to protect mitochondria from oxidation, while TXNRD1 protects the cytosol. Further, TXNRD1 upregulation is associated with the suppression of other selenoproteins, suggesting that NRF2 activation causes an imbalance in selenium distribution. Given the key role of selenoprotein in redox biology, the switch in the production of the different selenoproteins induced by NRF2 activation may create novel vulnerabilities of NRF2 active NSCLC with therapeutic potential. This proposal is designed to further strengthen these observations by defining the mechanistic basis of how GSR contributes to NRF2-mediated resistance to oxidative stress, and to leverage the imbalanced selenoprotein translation to develop potent therapeutic strategies for KEAP1/NRF2 mutant NSCLC. The following specific aims are pursued in this application: Aim 1. Investigate the role of GSR in NRF2-mediated resistance to oxidative stress. Aim 2. Define the role of NRF2 as a modulator of the selenoproteome in NSCLC. The knowledge and scientific expertise that I acquire from these proposed studies will facilitate my transition to an independent position. My long-term goal is to study the antioxidant enzymes in cancer, with a major focus on selenoproteins. In addition to the scientific goal, I have outlined a detailed career development plan to obtain skillsets that are key for leading a research laboratory and establishing a strong research program. I will conduct the proposed research and carry out the training plan under the guidance of my mentoring committee. I will embark on the excellent academic environment provided by Moffitt Cancer Center to achieve these goals and transition to an independent position.