Targeting Gq pathway in uveal melanoma

葡萄膜黑色素瘤中的靶向 Gq 通路

• 批准号: 10700134
• 负责人: Xu Chen
• 金额: $ 44.52万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-07 至 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10700134
• 关键词: Automobile Driving; BRAF gene; Buffers; CRISPR/Cas technology; Cardiolipins; Cell Proliferation; Cell Survival; Cells; Clinical; Combined Modality Therapy; Coupled; Data; Dependence; Development; Diglycerides; Disease; Disease model; Endothelin; Endothelin-1; Engineering; Environment; Enzymes; Exposure to; Eye; Family member; Feedback; G-Protein-Coupled Receptors; GNAQ gene; Gene Mutation; Genes; Genetic Engineering; Goals; Immune checkpoint inhibitor; In Vitro; Knock-in Mouse; Knock-out; Knockout Mice; Ligands; Lipid Synthesis Pathway; Lipids; Liver; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Melanoma Cell; Metastatic Neoplasm to the Liver; Metastatic to; Methods; Mitogen-Activated Protein Kinases; Mutation; NF1 gene; Nature; Neoplasm Metastasis; Oncogenic; Pathway interactions; Patients; Phenotype; Phosphatidylinositols; Phospholipase C; Phosphorylation; Protein Kinase C; Protein Kinase C Inhibitor; Regimen; Regulation; Resistance; Role; Second Messenger Systems; Signal Pathway; Signal Transduction; Somatic Mutation; Testing; Therapeutic; Therapeutic Effect; Treatment Efficacy; United States; Up-Regulation; Uveal Melanoma; Work; Xenograft Model; Xenograft procedure; clinical efficacy; clinically relevant; effective therapy; experimental study; genome-wide; immune checkpoint blockade; improved; in vivo; inhibitor; loss of function; melanocyte; melanoma; mortality; mouse model; new therapeutic target; novel; novel therapeutic intervention; overexpression; phosphatidate; phosphatidylcholine-specific phospholipase C; phosphoproteomics; receptor; resistance mechanism; subcutaneous; success; targeted treatment; therapeutic target; therapeutically effective; transcriptional reprogramming; transcriptome sequencing; tumor

Project summary: Uveal melanoma (UM) is the most common intraocular cancer in the United States and accounts for about 5% of all kinds of melanomas. Approximate 50% of UM patients develop metastases, predominantly to the liver with 100% mortality. UM lacks mutations in BRAF, NRAS, NF1 and KIT common to other melanoma types. Instead, over 90% harbor somatic activating mutations in the Gaq family members GNAQ or GNA11, with the remainder carrying mutations of genes also acting in the Gaq signaling pathway such as CYSLTR2, a Gaq- coupled GPCR, phospholipases C b4 (PLCb4), a direct effector of Gaq. Therefore, UM is genetically defined by activating mutations of the Gaq pathway. Despite dramatic successes in other melanoma subtypes, immune checkpoint inhibitors and targeted therapies have failed to demonstrate clinical benefits in UM, leading to an urgent need to develop novel and effective therapeutic regimens. The CYSLTR2->Gaq->PLCb-> protein kinase C (PKC) module is a linear signaling cascade that drives the essential MAP-kinase (MAPK) signaling for UM cell proliferation, making Gaq pathway the prime target for targeted therapy for this devasting disease. Although both GNAQ/11 and PKC inhibitors are very effective to suppress UM cell proliferation/survival in vitro, targeting either GNAQ/11 or PKC alone has shown limited efficacy in UM liver metastasis. Understanding the resistance to the Gaq pathway inhibition is of paramount importance to develop new strategies that work in the specific signaling context of a constitutively activated Gaq pathway. Our preliminary data show either GNAQ/11 inhibition or PKC inhibition yields strong upregulation of the Gaq-coupled receptor EDNRB, which when encountering its ligand EDN1 from the liver environment can lead to reactivation of MAPK, thus driving resistance to Gaq pathway inhibition in UM. In this proposal, we will evaluate that blocking endothelin signaling will increase the therapeutic efficacy of targeting oncogenic Gaq signaling, directly or downstream, using newly developed genetically engineered and xenograft models of UM metastatic to the liver. While the role of endothelin signaling in melanocyte development and melanoma progression is well documented, the nature of the feedback that upregulates EDNRB expression/signaling is not understood. We will utilize a combination of candidate approaches, RNAseq and phospho-proteomics to dissect the underlying mechanisms in UM cells and in melanocytes. Our preliminary data also show that secondary mutations in GNA11 can confer resistance to the Gaq inhibition. In this proposal, we will expand the emerging landscape of the mechanism underlying the adaptive and acquired resistance to Gaq pathway inhibition and identify rational therapy combinations to improve the therapeutic efficacy for metastatic UM. Using a combined genome-wide CRISPR/Cas9 synthetic lethality screen and phospho-proteomic screen we identified a lipid synthesis pathway that is essential for the survival of cells with Gaq mutation, which we will explore as entirely novel therapeutic target for UM.

项目摘要： 卵巢黑色素瘤（UM）是美国最常见的人类癌症，约为 各种黑色素瘤中有5％。大约50％的UM患者发展转移，主要是肝脏 具有100％死亡率。 UM缺乏BRAF，NRAS，NF1和其他黑色素瘤类型常见的套件。 取而代 其余的携带基因突变也作用于Gaq信号传导途径，例如cysltr2，gaq- 耦合GPCR，磷脂酶C B4（PLCB4），GAQ的直接效应子。因此，um是由遗传定义的 激活GAQ途径的突变。尽管在其他黑色素瘤亚型中取得了巨大成功，但免疫 检查点抑制剂和靶向疗法未能证明UM的临床益处，导致 迫切需要开发新颖有效的治疗方案。 cysltr2-> gaq-> plcb->蛋白激酶 C（PKC）模块是一个线性信号级联 扩散，使GAQ途径成为这种破坏性疾病的靶向治疗的主要靶标。虽然两者兼而有之 GNAQ/11和PKC抑制剂在体外抑制UM细胞增殖/存活非常有效，靶向 仅GNAQ/11或PKC在UM肝转移中的功效有限。了解对 GAQ途径抑制对于制定在特定信号中起作用的新策略至关重要 组成性激活的GAQ途径的上下文。我们的初步数据显示GNAQ/11抑制或PKC 抑制作用会产生GAQ耦合受体EDNRB的强烈上调，在遇到其配体时 来自肝脏环境的EDN1可以导致MAPK重新激活，从而推动对GAQ途径的阻力 UM抑制作用。在此提案中，我们将评估阻断内皮素信号会增加治疗性 直接或下游靶向致癌性GAQ信号的功效，使用新开发的遗传学 UM转移性肝脏的工程和异种移植模型。而内皮素信号在 黑色素细胞的发育和黑色素瘤进展已得到充分记录，反馈的性质 尚不清楚上调EDNRB表达/信号传导。我们将利用候选人的组合 方法，RNASEQ和磷酸 - 蛋白质组学以剖析UM细胞中的基本机制和 黑素细胞。我们的初步数据还表明，GNA11中的次要突变可以赋予对 GAQ抑制。在此提案中，我们将扩大该机制的新兴景观 自适应和获得的对GAQ途径抑制的抵抗力并确定合理治疗组合以改进 转移性UM的治疗功效。使用全基因组CRISPR/CAS9合成致死性 屏幕和磷酸 - 蛋白质筛选我们确定了一种脂质合成途径，这对于生存至关重要 具有GAQ突变的细胞，我们将作为UM的完全新颖的治疗靶点探索。