Biology of R-Spondin-Induced Sensitization to Asparaginase in Colorectal Cancer

R-Spondin 诱导结直肠癌天冬酰胺酶敏感性的生物学

• 批准号: 10297173
• 负责人: LUKAS Edward DOW
• 金额: $ 65.14万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10297173
• 关键词: Address; Alleles; Amino Acids; Asparagine; Biology; Cancer Etiology; Cell physiology; Cells; Cessation of life; Clinical; Clinical Trials; Colorectal Cancer; Data; Development; Disease; Drug resistance; Engineering; Epithelial Cells; Event; Generations; Genetic Engineering; Genetic Screening; Genetically Engineered Mouse; Hematopoietic; Human; Hypersensitivity; Immunotherapy; Impairment; Intestines; KRAS oncogenesis; KRAS2 gene; Knowledge; Life; Ligands; Maps; Mediating; Modeling; Molecular; Mus; Mutation; Oncogenic; Organoids; Outcome; Pathway interactions; Patients; Pharmacology; Phase; Proteins; Resistance; Role; Series; Signal Transduction; Source; Starvation; System; TP53 gene; Testing; Therapeutic; Therapeutic Index; Therapeutic Intervention; Toxic effect; Translating; Ubiquitin; Ubiquitination; WNT Signaling Pathway; asparaginase; base; beta catenin; bone; cancer cell; colon cancer cell line; colorectal cancer treatment; design; effective therapy; genome-wide; improved; inhibitor/antagonist; innovation; insight; leukemia; mortality; mouse model; multicatalytic endopeptidase complex; predictive modeling; progenitor; prospective; protein activation; protein degradation; receptor; response; syndecan; targeted treatment; therapy resistant; treatment response; tumor

ABSTRACT Colorectal cancer (CRC) is the second-leading cause of cancer deaths in the US, and unlike many other tumor types, there are no known effective therapies targeting dominant oncogenic drivers. Almost all CRCs have mutations that activate canonical Wnt/β-catenin signaling, but direct inhibition of β-catenin is difficult, and blocking Wnt ligand activity leads to significant on-target bone toxicity. Thus, while targeting Wnt directly is challenging, aberrant Wnt pathway activation may induce tumor-specific vulnerabilities that can be exploited for CRC therapy. Using a genome-wide genetic screen, we found that Wnt activation induces profound sensitization to therapeutic asparagine depletion using asparaginase in drug-resistant leukemias. This effect is dependent on Wnt-induced inhibition of GSK3, but is independent of APC or β-catenin. Instead, asparaginase sensitization is mediated by Wnt-induced inhibition of GSK3-dependent protein degradation, a catabolic source of amino acids required for asparaginase resistance. CRC provides a unique context in which to test predictions from our model, because these tumors almost all have mutations that activate Wnt/β-catenin, but these can function either upstream or downstream of GSK3. Using human CRC cell lines and genetically engineered mouse intestinal organoids, we found that asparaginase had little effect on CRCs with mutations of the downstream Wnt factor APC, but was profoundly toxic to cases with R-spondin translocations, which activate Wnt signaling via ligand-induced inhibition of GSK3, and thus inhibit GSK3-dependent protein degradation. Importantly, this approach has little detectable toxicity to normal intestinal or epithelial cells. This suggests that this approach has a potent therapeutic index that could transform clinical outcomes for the thousands of patients who die of CRC every year, and a clinical trial based on these data is under development. However, we do not understand key aspects of the biology underlying this RSPO/Wnt-induced therapeutic vulnerability. Defining the precise molecular events that dictate RSPO/Wnt induced asparaginase sensitivity is critical for prospectively identifying clinical responders, designing rational approaches to improve therapeutic response, and overcoming treatment resistance. These knowledge gaps will be addressed in the following Aims: 1) Determine how RSPO ligands induce sensitization to asparaginase. 2) Investigate the role of GSK3α body formation as a cellular response to asparagine starvation. 3) Determine the role of oncogenic KRAS and TP53 mutations in therapeutic response of RSPO fusion CRC to asparaginase. This proposal is expected to provide fundamental insights into the amino acid starvation response and its impairment by aberrant Wnt signaling, cellular processes fundamental to metazoan life whose molecular basis and therapeutic exploitation remain poorly understood. Given our highly complementary expertise in asparaginase biology and Wnt signaling, this MPI team is uniquely poised to translate these advances into highly innovative therapeutic interventions.

抽象的 结直肠癌 (CRC) 是美国癌症死亡的第二大原因，与许多其他肿瘤不同 类型，目前还没有针对主要致癌驱动因素的已知有效疗法。几乎所有的 CRC 都有 激活经典 Wnt/β-连环蛋白信号传导的突变，但直接抑制 β-连环蛋白很困难，并且 阻断 Wnt 配体活性会导致显着的靶向骨毒性。因此，虽然直接靶向 Wnt 具有挑战性的、异常的 Wnt 通路激活可能会诱导肿瘤特异性的漏洞，这些漏洞可用于 结直肠癌治疗。通过全基因组遗传筛选，我们发现 Wnt 激活可诱导深远的影响 在耐药性白血病中使用天冬酰胺酶对治疗性天冬酰胺消耗敏感。这个效果是 依赖于 Wnt 诱导的 GSK3 抑制，但不依赖于 APC 或 β-连环蛋白。相反，天冬酰胺酶 致敏作用是通过 Wnt 诱导的 GSK3 依赖性蛋白降解（一种分解代谢来源）的抑制来介导的 天冬酰胺酶抗性所需的氨基酸。 CRC 提供了一个独特的测试环境 来自我们模型的预测，因为这些肿瘤几乎都具有激活 Wnt/β-catenin 的突变，但是 它们可以在 GSK3 的上游或下游发挥作用。使用人类结直肠癌细胞系和基因 在工程化小鼠肠道类器官中，我们发现天冬酰胺酶对突变的 CRC 几乎没有影响 下游 Wnt 因子 APC，但对 R-spondin 易位病例具有极大的毒性，这 通过配体诱导的 GSK3 抑制激活 Wnt 信号传导，从而抑制 GSK3 依赖性蛋白 降解。重要的是，这种方法对正常肠道或上皮细胞几乎没有可检测到的毒性。这 表明这种方法具有有效的治疗指数，可以改变临床结果 每年有数千名患者死于结直肠癌，基于这些数据的临床试验正在进行中 发展。然而，我们不了解 RSPO/Wnt 诱导的生物学基础的关键方面 治疗脆弱性。定义决定 RSPO/Wnt 诱导天冬酰胺酶的精确分子事件 敏感性对于前瞻性地识别临床反应者、设计合理的方法来改善临床反应至关重要 治疗反应，并克服治疗抵抗。这些知识差距将在 以下目标： 1) 确定 RSPO 配体如何诱导对天冬酰胺酶的敏化。 2）调查角色 GSK3α 体形成作为细胞对天冬酰胺饥饿的反应。 3）确定致癌作用 RSPO 融合 CRC 对天冬酰胺酶治疗反应中的 KRAS 和 TP53 突变。这个提议是 预计将为氨基酸饥饿反应及其损害提供基本见解 异常的 Wnt 信号传导，是后生动物生命的基础细胞过程，其分子基础和 治疗性利用仍知之甚少。鉴于我们在天冬酰胺酶方面的专业知识高度互补 生物学和 Wnt 信号传导，这个 MPI 团队独特地准备将这些进步转化为高度创新 治疗干预。