Project 3: Mechanisms and therapeutic targeting of NRAS in melanoma

项目3：NRAS在黑色素瘤中的作用机制和治疗靶向

• 批准号: 9074409
• 负责人: ADRIENNE D COX
• 金额: $ 15.2万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-22 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9074409
• 关键词: Address; Alleles; Automobile Driving; Biochemical; Biological; Carcinoma; Cell Line; Cells; Codon Nucleotides; Collaborations; Combined Modality Therapy; Cutaneous Melanoma; Dependence; Dependency; Disease; Etiology; FRAP1 gene; Genetic Screening; Goals; Growth; HRAS gene; Human; Incidence; Individual; KRAS2 gene; Large Intestine Carcinoma; Lead; Learning; MEKs; Malignant Epithelial Cell; Malignant Neoplasms; Malignant neoplasm of pancreas; Melanoma Cell; Membrane; Methodology; Mitogen-Activated Protein Kinases; Molecular; Mus; Mutate; Mutation; Neoplasm Metastasis; Oncogenes; Oncogenic; Outcome; Pancreatic carcinoma; Pathway interactions; Phenotype; Property; Protein Isoforms; Proteins; Proto-Oncogene Proteins c-akt; RALGDS gene; Regulation; Role; Signal Pathway; Signal Transduction; Skin Cancer; System; Therapeutic; Transducers; addiction; base; cell motility; effective therapy; gain of function; innovation; knock-down; leukemia; lung Carcinoma; melanocyte; melanoma; mutant; neglect; novel; novel therapeutics; protein function; subcellular targeting; therapeutic target; tumorigenesis; tumorigenic

ABSTRACT Much remains to be learned about how RAS isoforms differ functionally from each other, and about the impact of specific mutations on each RAS protein. NRAS-mutant melanoma represents both a critical unmet need in terms of efficacious therapeutic options and also an outstanding opportunity to elucidate these functional differences. Although KRAS is the predominant RAS isoform mutated in cancers overall, NRAS is the predominant RAS isoform mutated in malignant melanoma, and whereas mutations at codon 61 are rare in KRAS, they predominate in NRAS. Project 2 has recently demonstrated that Nras Q61R but not G12D could drive melanoma formation in Ink4a-deficient mice. These provocative findings indicate that NRAS Q61R and G12D must activate distinct effectors, and/or activate effectors in a distinct manner. Given the preferential occurrence of NRAS Q61 mutations in melanoma, we propose studies to elucidate the signaling mechanisms that distinguish the roles of Q61- versus G12-mutant NRAS in driving these cancers. We hypothesize that there are structural, biochemical and biological properties distinct from those of the more common G12-mutant KRAS proteins found in lung, colorectal and pancreatic carcinomas. We have also identified an unexpected requirement for both KRAS and HRAS WT forms in NRAS-mutant melanomas. We will investigate effector signaling mechanisms driven by different NRAS mutants, define the requirements for WT isoforms, and leverage both candidate- and unbiased methodologies to identify targets that can lead to novel combination therapies for effective treatment of NRAS-driven melanomas. To address our goals, we propose three aims. In Aim 1, we will elucidate known and unknown effector signaling pathways downstream of cellular NRAS mutated at codon 61 versus codon 12. This Aim will be performed in close collaboration with Project 2, which will focus on structural and biochemical differences in the same panel of NRAS mutants. Projects 1 and 4 will also examine some of the cellular and tumorigenic phenotypes of the same mutations in different RAS isoforms. In Aim 2, we will characterize the requirement for WT RAS isoforms, and determine functional differences in effectors and signaling networks, as well as in transformed growth properties. In Aim 3, we will determine whether the same mechanisms that overcome melanoma addiction to mutant NRAS also overcome dependency on WT RAS isoforms. To do this, we will first interrogate YAP, known to be capable of rescuing addiction to mutant KRAS in carcinomas, and we will next perform a novel functional genetic screen to identify non-YAP mechanisms in an unbiased manner. Collectively, our studies will elucidate a better understanding of the neglected NRAS isoform, characterize functional distinctions among different NRAS mutations, determine relationships between WT and mutant NRAS-driven effector signaling pathways and networks, and identify new directions for novel therapeutic options in NRAS-driven melanoma.

抽象的 关于RAS同工型如何彼此功能以及影响的影响，还有很多尚待了解 每个RAS蛋白上的特定突变。 NRAS突变黑色素瘤既代表 有效的治疗选择的条款，也是阐明这些功能的出色机会 差异。尽管KRAS是癌症中总体突变的主要RAS同工型，但NRA是 在恶性黑色素瘤中突变的主要RAS同工型，而密码子61的突变在很少见 克拉斯（Kras），他们在NRA中占主导地位。项目2最近证明了NRAS Q61R，但G12D不能 在Ink4a缺陷小鼠中驱动黑色素瘤形成。这些挑衅性的发现表明NRAS Q61R和 G12D必须以不同的方式激活不同的效应子和/或激活效应子。给定优先 NRAS Q61突变发生在黑色素瘤中，我们提出了研究以阐明信号传导机制 这区分了Q61-与G12突变的NRA在驱动这些癌症中的作用。我们假设这一点 有结构，生化和生物学特性与更常见的G12突变物不同 在肺，结直肠和胰腺癌中发现的KRAS蛋白质。我们还确定了一个意外的 NRAS突变黑色素瘤中KRAS和HRAS WT形式的需求。我们将调查效应器 由不同的NRA突变体驱动的信号传导机制，定义了WT同工型的要求，并 利用候选和无偏见的方法来识别可以导致新型组合的靶标 有效治疗NRAS驱动的黑色素瘤的疗法。为了解决我们的目标，我们提出了三个目标。在 AIM 1，我们将阐明细胞NRA下游的已知和未知效应子信号通路 在密码子61与密码子12中进行突变。此目标将与项目2密切合作进行，该目标将 将重点放在同一NRA突变体的结构和生化差异上。项目1和4将 还要检查不同RAS中相同突变的一些细胞和肿瘤表型 同工型。在AIM 2中，我们将表征WT RAS同工型的需求，并确定功能 效应子和信号网络以及转化的生长特性的差异。在AIM 3中，我们将 确定是否也克服了突变体NRA的黑色素瘤成瘾的相同机制也克服了 对WT RAS同工型的依赖性。为此，我们将首先询问YAP，该YAP能够营救 对癌中突变KRA的成瘾，我们接下来将执行一种新型的功能遗传筛选以识别 非YAP机制以公正的方式。总的来说，我们的研究将阐明对 被忽视的NRA同工型，表征不同NRA突变之间的功能区别，确定 WT与NRAS驱动的效应子信号通路和网络之间的关系，并识别 NRAS驱动的黑色素瘤新型治疗选择的新方向。