EGFR signaling in osteoarthritis and treatment

骨关节炎中的 EGFR 信号传导及其治疗

• 批准号: 10701673
• 负责人: Ling Qin
• 金额: $ 44.28万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-30 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10701673
• 关键词: Adult; Age Years; Aging; Animal Model; Animals; Arthralgia; Attenuated; Biology; Bovine Cartilage; CREB1 gene; Cartilage; Cells; Chondrocytes; DTR gene; Data; Degenerative polyarthritis; Development; Disease; Elderly; Epidermal Growth Factor Receptor; Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor; Gefitinib; General Population; Genes; Growth Factor; Health; Histology; Homeostasis; Hypertrophy; Joints; Knee; Knee Osteoarthritis; Knowledge; Life; Ligands; Lubrication; Mechanics; Mediating; Modeling; Molecular; Mus; Operative Surgical Procedures; Pain; Pathogenesis; Pathway interactions; Penetration; Personal Satisfaction; Pharmaceutical Preparations; Pharmacotherapy; Phenotype; Prevalence; Proteoglycan; Receptor Protein-Tyrosine Kinases; Receptor Signaling; Regulation; Resolution; Role; Sclerosis; Series; Signal Pathway; Somatotropin; Structure; Surface; Testing; Therapeutic Effect; Transforming Growth Factor alpha; Translating; age related; aggrecan; arthropathies; articular cartilage; behavior test; cartilage degradation; clinically relevant; design; disability; experimental study; gain of function; genetic approach; genetic manipulation; improved; knock-down; loss of function; mechanical properties; mouse model; nanoparticle; novel; novel therapeutic intervention; overexpression; prevent; repaired; response; subchondral bone

Project Summary Osteoarthritis (OA) is a classic age-related disorder and the most common cause ofpain and disability in the elderly. It is primarily characterized by the progressive destruction of articular cartilage. This past decade has witnessed significant advances in deciphering the basic mechanisms by which OA develops. However, to date, no disease modifying drug therapy is available for preventing OA development and repairing the degenerative cartilage. The uppermost superficial zone of articular cartilage is the first line of defense against OA initiation. We recently found that epidermal growth factor receptor (EGFR), a tyrosine kinase receptor, is expressed abundantly throughout the articular cartilage with its active form (p-EGFR) predominantly located in the superficial zone. Interestingly, at the onset of OA, p-EGFR amount, along with two major EGFR ligands (TGFα and HBEGF), were markedly attenuated while the amount of Mig6, a negative inhibitor of EGFR, was enhanced, suggesting a potential role for EGFR signaling pathway in cartilage homeostasis and diseases. Using a series of mouse models with deficient or overactivated EGFR activity by genetic manipulation of Egfr and Mig6 genes, we and others have demonstrated that EGFR signaling is critical for maintaining the number and mechanical properties of superficial chondrocytes, suppressing their hypertrophy, promoting proteoglycan 4 (Prg4) expression, and stimulating surface lubrication function. Most strikingly, in aging- and surgery-induced OA models, mice with chondrocyte-specific (Col2-Cre) EGFR deficiency developed the most severe OA phenotypes, including a complete loss of articular cartilage, subchondral bone sclerosis, and escalated joint pain. Hence, we hypothesize that EGFR signaling is essential for maintaining the structure and function of the superficial layer in the articular cartilage and thus, can be targeted for OA treatment. Our objectives are to understand the role of this novel signaling pathway in articular cartilage homeostasis and diseases, and to seek approaches targeting this pathway for OA treatment. To achieve these, we will perform the following aims: 1) determine the temporal role of EGFR signaling in OA pathogenesis; 2) elucidate the mechanisms of the protective action of EGFR on articular cartilage; 3) investigate whether EGFR signaling is a promising target for OA treatment. Complementary genetic approaches, such as EGFR vs Mig6, loss of function vs gain of function, and aggrecan-CreER vs Prg4-CreER, will be used throughout the proposal. Moreover, we have designed and synthesized TGFα-conjugated nanoparticles with prolonged retention and penetration abilities in knee cartilage. A proof-of-principal experiment will be performed to examine its therapeutic effects on cartilage degeneration at different OA stages. This proposal will uncover critical EGFR actions in knee articular cartilage and provide crucial evidence for targeting this novel pathway in OA therapies. Once successfully accomplished, this project could be quickly translated into large animal OA models followed by clinically relevant applications that would eventually improve the health and well-being of the general public.

项目摘要 骨关节炎（OA）是一种典型的年龄相关性疾病，也是老年人疼痛和残疾的最常见原因。 的 老人 其主要特征是关节软骨的进行性破坏。过去十年 在解释OA发展的基本机制方面取得了重大进展。但要 迄今为止，没有疾病修饰药物治疗可用于预防OA发展和修复 退化的软骨关节软骨的最上面的浅表区是抵抗关节炎的第一道防线。 OA启动。我们最近发现表皮生长因子受体（EGFR），一种酪氨酸激酶受体， 在整个关节软骨中大量表达，其活性形式（p-EGFR）主要位于关节软骨中， 表面区域。有趣的是，在OA发病时，p-EGFR的量，沿着两个主要的EGFR配体， (TGFα和HBEGF）的量显著减弱，而EGFR的阴性抑制剂Mig 6的量显著减少。 增强，表明EGFR信号通路在软骨稳态和疾病中的潜在作用。 通过基因操作EGFR，使用一系列EGFR活性缺陷或过度激活的小鼠模型 和Mig 6基因，我们和其他人已经证明EGFR信号传导对于维持细胞数量至关重要。 和机械性能，抑制其肥大，促进蛋白聚糖 4（Prg 4）表达，并刺激表面润滑功能。最引人注目的是，在衰老和手术引起的 在OA模型中，软骨细胞特异性（Col 2-Cre）EGFR缺陷的小鼠发展为最严重的OA 表型，包括关节软骨的完全丧失，软骨下骨硬化和关节炎的升级。 痛苦因此，我们假设EGFR信号传导对于维持细胞的结构和功能是必不可少的。 在关节软骨中的浅表层，因此可以靶向用于OA治疗。我们的目标为 了解这种新的信号通路在关节软骨稳态和疾病中的作用， 寻求针对该途径的OA治疗方法。为了实现这些目标，我们将执行以下操作 目的：1）确定EGFR信号传导在OA发病机制中的时间作用; 2）阐明 EGFR对关节软骨保护作用; 3）研究EGFR信号传导是否是一种有前途的 用于OA治疗。互补遗传方法，如EGFR vs Mig 6，功能丧失vs获得 和聚集蛋白聚糖-CreER与Prg 4-CreER，将在整个提案中使用。而且我们 设计并合成了TGFα结合的纳米颗粒，具有延长的保留和渗透能力， 膝盖软骨将进行一项主要实验来验证其对软骨的治疗效果 在不同的OA阶段退化。该提案将揭示膝关节软骨中EGFR的关键作用 并为在OA治疗中靶向这一新途径提供了重要证据。一旦成功 完成后，该项目可以快速转化为大型动物OA模型，然后进行临床研究。 最终将改善公众健康和福祉的相关应用。