Mechanisms and Treatment of Hajdu Cheney Syndrome

Hajdu Cheney 综合症的机制和治疗

• 批准号: 10263404
• 负责人: Ernesto Canalis
• 金额: $ 36.08万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10263404
• 关键词: Acro-Osteolysis; Affect; Alleles; Antisense Oligonucleotides; Antisense Technology; Behavior; Bone Resorption; Bone remodeling; Cell Differentiation process; Cell Line; Cells; Clinical; Cytolysis; Dependence; Development; Disease; Disease model; Distal; ES01; Effectiveness; Enhancers; Event; Exhibits; Exons; Fracture; Genes; Genetic Diseases; Goals; Hajdu-Cheney Syndrome; Human; In Vitro; Intervention; Investigation; Knowledge; Lead; Ligands; Modeling; Mus; Mutant Strains Mice; Mutation; Myelogenous; Nuclear; Osteoblasts; Osteoclasts; Osteopenia; Other Genetics; Phalanx; Phenotype; Play; Positioning Attribute; Proteins; Regulation; Research; Role; Secondary to; Skeleton; Syndrome; TRANCE protein; Testing; Therapeutic Intervention; Ubiquitination; Work; bone; bone loss; craniofacial; gain of function; human disease; human model; in vivo; induced pluripotent stem cell; mouse model; mutant; notch protein; novel; novel therapeutic intervention; osteoclastogenesis; overexpression; premature; prevent; receptor expression; skeletal; tomography

PROJECT SUMMARY/ABSTRACT Notch receptors play a critical role in cell fate decisions and in the regulation of bone remodeling, either directly or through the induction of their target genes, namely Hairy Enhancer of Split (Hes) and Hes-related with YRPW motif (Hey). Hajdu Cheney Syndrome (HCS) is a devastating disease characterized by developmental abnormalities, acroosteolysis and bone loss with fractures. HCS is associated with mutations in exon 34 of NOTCH2 upstream of the PEST domain leading to NOTCH2 stabilization and gain-of-function. We created a mouse model of HCS (Notch2tm1.1Ecan) that presents with osteopenia due to enhanced osteoclastogenesis and bone resorption. These events are secondary to an increase in receptor activator of nuclear factor Kappa B ligand (RANKL) by cells of the osteoblast lineage, and to direct effects of NOTCH2 in cells of the myeloid lineage. In this lineage, the expression of HES1 is induced by NOTCH2 and the inactivation of Hes1 in the osteoclast lineage reverses the in vitro and in vivo phenotype of HCS mutants. Moreover, HES1 induces osteoclastogenesis directly and as a result causes osteopenia in vivo. This reveals a previously unrecognized function of HES1 in osteoclast differentiation and function that will be explored as part of the proposed research. An additional goal of the proposed work is to develop ways to correct the skeletal manifestations of HCS by targeting the mutation with Notch2 antisense oligonucleotides (ASO), a strategy that would be applicable to other genetic disorders of the skeleton. Our specific aims are: Aim 1) To determine the role of HES1 in osteoclastogenesis. Our goals are to induce and inactivate Hes1 specifically in cells of the osteoclast lineage to determine its contribution to osteoclast differentiation and bone remodeling as determined by microcomputed tomography and histomorphometry; Aim 2) To establish that the Notch2tm1.1Ecan mutation can be targeted. We will determine whether the Notch2tm1.1Ecan mutation can be downregulated specifically and the Notch2tm1.1Ecan skeletal phenotype ameliorated by the administration of antisense oligonucleotides targeting the Notch26955C>T mutation; and Aim 3) To validate the mechanisms of the HCS phenotype and ASO approach in NOTCH2 mutant-induced pluripotent (iPS) cells. To this end, we created NOTCH2HCS mutant iPS cell lines to study the impact of the mutation on osteoclastogenesis and the efficacy of ASOs in downregulating NOTCH2 mutant alleles. The goals of the proposed work are to understand the mechanisms and develop specific antisense technology to treat the skeletal manifestations of a devastating NOTCH2-associated disease.

项目摘要/摘要 Notch受体在细胞命运决策中起着至关重要的作用 直接或通过诱导其靶基因，即分裂（HES）和HES相关的毛状增强子 使用YRPW图案（嘿）。 Hajdu Cheney综合征（HCS）是一种毁灭性疾病，其特征是 发育异常，丙烯酸溶解和骨折骨质流失。 HCS与突变有关 Notch2的外显子34上游的害虫结构域，导致Notch2稳定和功能获得。我们 创建了由于增强的骨质减少症的HCS（Notch2tm1.1can）的鼠标模型 破骨细胞生成和骨吸收。这些事件是继发于受体激活因子的继发 核因子kappa b配体（RANKL）由成骨细胞谱系的细胞，并导致Notch2在 髓样谱系的细胞。在此谱系中，HES1的表达是由Notch2诱导的 HES1在破骨细胞谱系中的失活会逆转HCS突变体的体外和体内表型。 此外，HES1直接诱导骨质核层生成，因此导致体内骨质减少症。这揭示了 以前将HES1在破骨细胞分化和功能中的功能未识别的功能将作为一部分探索 拟议的研究。拟议工作的另一个目标是开发纠正骨骼的方法 通过使用Notch2反义寡核苷酸（ASO）靶向突变，HC的表现是一种策略 将适用于骨骼的其他遗传疾病。我们的具体目的是：目标1）确定 HES1在破骨细胞生成中的作用。我们的目标是专门在细胞中诱导和灭活HES1 破骨细胞谱系确定其对破骨细胞分化和骨骼重塑的贡献如确定 通过微型层析成像和组织形态计量学；目标2）确定Notch2tm1.1can突变可以 是针对性的。我们将确定notch2tm1.1can突变是否可以专门下调，以及 Notch2tm1.1can骨骼表型通过靶向的反义寡核苷酸来改善 Notch26955C> t突变；目标3）验证HCS表型和ASO方法的机制 Notch2突变诱导的多能（IPS）细胞。为此，我们创建了Notch2HCS突变体IPS细胞系 研究突变对破骨细胞生成的影响和ASOS下调的疗效 Notch2突变等位基因。拟议工作的目标是了解机制并发展 特定的反义技术治疗毁灭性Notch2相关的骨骼表现 疾病。