Investigating YAP1 control of differentiation and metabolism in Hepatoblastoma

研究 YAP1 对肝母细胞瘤分化和代谢的控制

• 批准号: 9761015
• 负责人: Jordan Leigh Smith
• 金额: $ 3.22万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-01 至 2023-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9761015
• 关键词: 5 year old; Adjuvant Chemotherapy; Affect; Affinity; Binding; Biochemical; Biological; Biological Assay; Child; Childhood; Childhood Liver Cancer; Clinical; Complex; DNA-Protein Interaction; Doxycycline; Enzymes; Excision; Gene Expression; Genes; Genetic; Genetic Transcription; Genetic screening method; Genomics; Glycolysis; Goals; Growth; HNF4A gene; Hepatoblastoma; Hepatocyte; Hyperactive behavior; In Vitro; Life; Liver; Liver Regeneration; Liver neoplasms; Maintenance; Malignant Neoplasms; Malignant neoplasm of liver; Measures; Messenger RNA; Metabolic; Metabolism; Modeling; Molecular; Mus; Nuclear; Operative Surgical Procedures; Pathway interactions; Patients; Pharmaceutical Preparations; Prognostic Factor; Prognostic Marker; Proteins; Pyruvate Kinase; RNA Interference; Regulation; Role; Signal Transduction; Specificity; Survival Rate; Testing; Therapeutic; Unresectable; beta catenin; cancer cell; carcinogenesis; clinically significant; druggable target; enzyme activity; flexibility; genetic signature; in vivo; in vivo Model; infancy; insight; mRNA Expression; meetings; mouse model; neoplastic cell; outcome forecast; overexpression; pediatric patients; prognostic; promoter; protein expression; small hairpin RNA; targeted treatment; therapeutic target; transcription factor; tumor; tumor metabolism; tumorigenesis

Project Summary Hepatoblastoma (HB), the most common pediatric primary liver tumor, affects children from infancy to five years of age. Surgical resection with adjuvant chemotherapy has saved many young lives. However, the five-year survival rate remains at 70%, and is worse for children with unresectable tumors. Meeting the clinical need for HB-targeted therapies requires a better understanding of how HB tumors are formed and maintained. The transcriptional co-regulator YAP1 is hyper-activated in 79% of HB cases, and recent studies suggest that YAP1 and the Wnt/β-catenin pathway act together to initiate HB tumors. But is YAP1 required to maintain HB tumorigenesis? Preliminary studies using a conditional mouse model of HB—driven by doxycycline-inducible hyperactive YAP1S127A and constitutively-active β-catenin—suggest that YAP1 is essential for tumor maintenance. In the presence of doxycycline, YAP1 is expressed, and mice develop HB tumors; withdrawing doxycycline turns off YAP1, resulting in >90% tumor regression within 10 weeks. Transcriptional analyses revealed that hepatocyte differentiation factors and liver metabolic genes were induced in regressing tumors. The goal of this proposal is to understand how YAP1 dysregulates hepatocyte differentiation and reprograms hepatocyte metabolism. Using a conditional mouse model of HB, Aim 1 will investigate how YAP1 regulates critical hepatocyte differentiation factors—HNF4a and FoxA2—to maintain HB tumorigenesis. Genetic tests will be used to determine whether HNF4a and FoxA2 are necessary or sufficient to promote tumor regression and differentiation. Genomic and biochemical approaches will be used to assess binding and affinity of the YAP1- TEAD complex to HNF4a and FoxA2 genes. Results from Aim 1 will provide insight into how YAP1 affects differentiation status and may have important prognostic implications for HB patients. Aim 2 will investigate how YAP1 maintains tumorigenesis by reprogramming hepatocyte metabolism. The glycolytic enzyme activity of pyruvate kinase M2 (Pkm2) will be measured in YAP1-dependent tumors and during tumor regression in conditional HB mice. RNA interference will be used to determine whether Pkm2 is required for YAP1-dependent tumor maintenance. This aim will examine previously uncharacterized YAP1 and Pkm2 regulation of tumor metabolism. Findings from this study will provide insight into the mechanisms of YAP1 in HB tumorigenesis and may define new prognostic factors and druggable targets to treat children suffering from HB.

项目摘要 肝母细胞瘤(HB)是儿科最常见的原发性肝肿瘤，影响儿童从婴儿期到五岁。 年纪大了。手术切除辅以化疗挽救了许多年轻的生命。然而，五年期 存活率保持在70%，对于患有无法切除的肿瘤的儿童来说，存活率更差。满足患者的临床需求 针对乙肝的治疗需要更好地了解乙肝肿瘤是如何形成和维持的。这个 转录共调节因子YAP1在79%的HB病例中过度激活，最近的研究表明YAP1 而Wnt/β-连环蛋白通路共同启动了HB肿瘤。但是YAP1需要维持Hb吗？ 肿瘤的发生？多西环素诱导条件小鼠Hb模型的初步研究 高活性的YAP1S127A和结构性活性的β-连环蛋白--表明YAP1在肿瘤中是必不可少的 维修。在多西环素存在的情况下，YAP1被表达，小鼠发展为HB肿瘤；退出 多西环素关闭YAP1，导致90%的肿瘤在10周内消退。转录分析 显示肝细胞分化因子和肝脏代谢基因在肿瘤消退过程中被诱导。 这项提案的目的是了解YAP1如何失调肝细胞分化和再编程 肝细胞代谢。使用Hb的条件小鼠模型，Aim 1将研究YAP1是如何调节的 关键的肝细胞分化因子-HNF4a和FOXA2-维持HB肿瘤的发生。基因测试将 用于确定HNF4a和FOXA2是否必要或足以促进肿瘤消退和 差异化。将使用基因组和生化方法来评估YAP1-的结合和亲和力 HNF4a和FOXA2基因的TEAD复合体。AIM 1的结果将让我们深入了解YAP1如何影响 分化状态，并可能对乙肝患者的预后有重要意义。AIM 2将调查如何 YAP1通过重新编程肝细胞代谢来维持肿瘤的发生。糖酵解酶活性的测定 将在YAP1依赖的肿瘤中和在肿瘤消退期间检测丙酮酸激酶M2(PKM2) 条件性HB小鼠。将使用RNA干扰来确定YAP1依赖是否需要PKM2 肿瘤维护。这一目标将检验以前未知的YAP1和PKM2对肿瘤的调控 新陈代谢。这项研究的发现将为深入了解YAP1在HB肿瘤发生和发展中的作用机制提供依据。 可能定义新的预后因素和可用药靶点来治疗患有乙肝的儿童。