Novel Strategies for Understanding and Treating Fibrous Dysplasia

理解和治疗纤维发育不良的新策略

• 批准号: 10658595
• 负责人: EDWARD C HSIAO
• 金额: $ 69.96万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10658595
• 关键词: Acceleration; Address; Affect; Artificial Intelligence; Automobile Driving; Binding; Biological Assay; Biological Markers; Biology; Bone Diseases; Bone Growth; Bone callus; Calvaria; Cells; Clinical; Complex; Cre driver; Cyclic AMP; DNA Sequence Alteration; Data; Disease; Dysplasia; Foundations; Fracture; Functional disorder; Future; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; GNAS gene; GTP-Binding Protein alpha Subunits, Gs; Gene Expression Profile; Genes; Genetic; Health; Hematopoietic stem cells; Homeostasis; Human; Hybrids; Hyperactivity; Individual; Institution; Isoproterenol; Kinetics; Knowledge; Lead; Lesion; Ligands; McCune-Albright Syndrome; Mediating; Medical; Modeling; Molecular; Molecular Probes; Mus; Musculoskeletal Diseases; Mutation; Natural regeneration; Osteitis Fibrosa Disseminata; Osteoblasts; Osteocytes; Osteogenesis; Osteoporosis; PTH gene; Pathology; Pathway interactions; Patients; Phenotype; Physiology; Production; Property; Proteins; Public Health; Recombinants; Role; Sampling; Signal Pathway; Signal Transduction; Signaling Molecule; Testing; Therapeutic; Variant; WNT Signaling Pathway; WNT4 gene; WNT9A gene; Wnt proteins; Work; analytical method; bone; bone cell; bone fracture repair; bone loss; bone repair; bone turnover; cell type; computational intelligence; digital; effective therapy; experience; genetic approach; guanine nucleotide binding protein; improved; in vivo evaluation; induced pluripotent stem cell; mouse model; novel; novel strategies; novel therapeutic intervention; novel therapeutics; osteogenic; overexpression; parathyroid hormone-related protein; pharmacologic; prevent; rare condition; receptor; repaired; single-cell RNA sequencing; skeletal; skeletal stem cell; stem cell function; stem cell model; therapeutic target; tool; transcriptome; transcriptomics; treatment strategy

PROJECT SUMMARY Current treatments for many musculoskeletal disorders are often suboptimal. Understanding the signals controlling skeletal homeostasis and repair is of high relevance, since this knowledge is critical for developing effective therapies for common conditions such as osteoporosis and fractures. In this proposal, we study fibrous dysplasia (FD) as a way to understand the regulators of human bone formation, and test if these pathways could then be used to enhance bone repair. FD accounts for 2.5% of all bone lesions and can occur as part of McCune-Albright Syndrome (MAS). FD is caused by genetic mutations in the GNAS locus, leading to a constitutively active Gs-GPCR protein, hence increasing cAMP levels and causing aberrant cellular signaling. Medical treatments for this disfiguring disorder are sorely lacking. This proposal uses new tools, including mouse models, human induced pluripotent stem cells (iPSCs), skeletal stem/progenitor cells, and advanced genetic strategies, to address the critical knowledge gaps and to find novel therapies for these medically significant conditions. We propose three specific aims: Aim 1: Identify novel compounds that directly target Gsα-regulated cAMP and Wnt production. We previously showed that stopping excess Gs-GPCR pathway activity in mice could dramatically reverse FD-like bone lesions. Using a new artificial intelligence computational approach, we found 71 candidate compounds predicted to selectively bind the GsαR201H protein. Preliminary studies demonstrate that some of these show the desired inhibition of GsαR201H-induced basal cAMP production. This Aim takes our top candidates and further characterizes their ability to block cAMP and Wnt activity, as potential molecular tools for manipulating GNAS. We also test if the lead compounds can reverse existing FD lesions in mouse calvarial cultures. Aim 2: Test if Wnt inhibition can prevent FD bone lesions in mice. How the GNAS mutations in FD cause dramatic bone formation is still poorly defined. We recently found that three proteins, Wnt4, Wnt5a, and Wnt9a, are upregulated in both mouse and human FD bone lesions. This Aim tests if blocking these proteins can reverse FD bone lesions in mice, and examines how each Wnt protein impacts FD lesion pathology. Aim 3: Determine the pathways that are dysregulated in human FD bone lesions and assess the roles of WNT signaling in human skeletal stem/progenitor cells during fracture repair. This aim uses advanced genetics on human FD bone samples to identify the malfunctioning cell types that cause FD. We also test how overactivating WNT4, WNT5a, or WNT9a in human skeletal stem/progenitor cells affect bone formation in a fracture healing model. These results will identify new targets for treating FD and for promoting fracture healing. This application address key knowledge gaps about which Wnt signaling molecules drive FD and how they impact human osteogenesis. The proposal comes from an established, strong, collaborative, multi-institutional team with extensive experience in GPCRs, FD, bone biology, and bone analytical methods. 1

项目总结 目前许多肌肉骨骼疾病的治疗方法往往不太理想。理解这些信号 控制骨骼的动态平衡和修复具有很高的相关性，因为这一知识对发育至关重要 对骨质疏松症和骨折等常见疾病的有效治疗。 在这项建议中，我们研究纤维异常增殖症(FD)，以此作为了解人类骨形成调控因素的一种方式。 然后测试这些途径是否可以用来增强骨骼修复。FD占所有骨骼病变的2.5% 并可作为麦考恩-奥尔布赖特综合征(MAS)的一部分发生。功能性消化不良是由GNAS基因突变引起的 基因座，导致具有结构活性的Gs-GPCR蛋白，从而增加cAMP水平并导致异常 细胞信号。对这种毁容疾病的医疗治疗严重缺乏。这项提案使用新的 工具包括小鼠模型、人类诱导多能干细胞(IPSCs)、骨骼干细胞/祖细胞， 和先进的遗传策略，以解决关键的知识差距并找到治疗这些疾病的新疗法 医学上意义重大的疾病。我们提出三个具体目标： 目的1：寻找直接靶向Gs、α调节的cAMP和Wnt产生的新化合物。我们 先前表明，在小鼠中停止Gs-GPCR途径的过度活动可以极大地逆转类FD 骨头损伤。使用一种新的人工智能计算方法，我们找到了71个候选化合物 预测与GsαR201H蛋白选择性结合。初步研究表明，其中一些研究表明 预期抑制GsαR201H诱导的基础cAMP生成。这一目标使我们的顶尖候选人更进一步 表征了它们阻断cAMP和Wnt活性的能力，作为操纵GNAS的潜在分子工具。 我们还测试了先导化合物是否可以逆转小鼠颅骨培养中现有的FD损害。 目的2：检测Wnt抑制是否能预防FD小鼠的骨损伤。功能性消化不良的GNAS突变是如何引起的 戏剧性的骨形成仍然没有明确的定义。我们最近发现了三种蛋白质，Wnt4，Wnt5a和Wnt9a， 在小鼠和人类FD骨损伤中均上调。这个目的是测试阻断这些蛋白质是否可以逆转 并检测每种Wnt蛋白对FD病变病理的影响。 目的3：确定在人类FD骨损伤中调节失调的通路，并评估其作用 骨折修复过程中人骨骼干/祖细胞中的WNT信号。这一目标使用先进的 对人类FD骨骼样本进行遗传学研究，以确定导致FD的功能障碍细胞类型。我们还测试了如何 人骨骼干/祖细胞中Wnt4、Wnt5a或WNT9a的过度激活影响骨形成 骨折愈合模型。这些结果将确定治疗FD和促进骨折愈合的新靶点。 这项应用解决了关于哪些Wnt信号分子驱动FD以及它们如何驱动FD的关键知识空白 影响人类的成骨能力。该提议来自一个成熟的、强大的、协作的、多机构的 在GPCRS、FD、骨生物学和骨分析方法方面拥有丰富经验的团队。 1