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

项目摘要 目前对许多肌肉骨骼疾病的治疗往往是次优的。了解信号 控制骨骼的稳态和修复是高度相关的，因为这方面的知识是至关重要的发展， 有效治疗常见疾病，如骨质疏松症和骨折。 在这个提议中，我们研究纤维性发育不良（FD）作为了解人类骨形成调节因子的一种方式， 并测试这些通路是否可以用于增强骨骼修复。FD占所有骨病变的2.5% 并且可以作为McCune-Albright综合征（MAS）的一部分发生。FD是由GNAS基因突变引起的 基因座，导致组成型活性Gs-GPCR蛋白，因此增加cAMP水平并引起异常的 细胞信号对这种毁容性疾病的医学治疗非常缺乏。该提案使用新的 工具，包括小鼠模型，人诱导多能干细胞（iPSC），骨骼干/祖细胞， 和先进的遗传策略，以解决关键的知识差距，并找到新的疗法，这些 医学上重要的条件。我们提出三个具体目标： 目的1：鉴定直接靶向Gsα调节的cAMP和Wnt产生的新化合物。我们 先前的研究表明，在小鼠中停止过量的Gs-GPCR途径活性可以显著逆转FD样 骨损伤使用一种新的人工智能计算方法，我们发现了71种候选化合物 预测选择性结合Gsα R201 H蛋白。初步研究表明，其中一些显示， 抑制Gsα R201 H诱导的基础cAMP产生。这一目标使我们的顶级候选人和进一步 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物中现有的FD病变。 目的2：测试Wnt抑制是否可以预防小鼠中的FD骨病变。FD中的GNAS突变如何导致 戏剧性的骨形成仍然不清楚。我们最近发现三种蛋白质，Wnt 4，Wnt 5a和Wnt 9a， 在小鼠和人FD骨病变中均上调。这个目标测试如果阻止这些蛋白质可以逆转 在小鼠中的FD骨病变，并检查每种Wnt蛋白如何影响FD病变病理学。 目的3：确定人类FD骨病变中失调的途径，并评估以下因素的作用： 骨折修复过程中人骨骼干/祖细胞中的WNT信号传导这一目标使用先进的 遗传学对人类FD骨骼样本，以确定故障的细胞类型，导致FD。我们还测试了 过度激活人骨骼干/祖细胞中的WNT 4、WNT 5a或WNT 9a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。 该应用程序解决了关于哪些Wnt信号分子驱动FD以及它们如何驱动FD的关键知识缺口。 影响人类骨生成。该提案来自一个既有、强大、协作、多机构的 在GPCR、FD、骨生物学和骨分析方法方面拥有丰富经验的团队。 1