Small molecule targeting an epigenetic regulator for the treatment of osteoarthritis

靶向表观遗传调节剂的小分子治疗骨关节炎

• 批准号: 10300923
• 负责人: Maddalena Adorno
• 金额: $ 45.29万
• 依托单位: DORIAN THERAPEUTICS, INC.
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-30 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10300923
• 关键词: Adult; Affect; Aging; Analgesics; Apoptosis; BMI1 gene; Bacterial Artificial Chromosomes; Biochemical; Biological Assay; Bone Marrow; CDKN2A gene; Cartilage; Catabolism; Cell Aging; Cells; Chondrocytes; Chromatin; Chromatin Remodeling Factor; Chromosome 21; Chronic; Clinical Trials; Collagen; Congenital Disorders; Data; Degenerative polyarthritis; Deposition; Development; Disease; Dose; Down Syndrome; Down-Regulation; Drug Kinetics; Enzymes; Epigenetic Process; Formulation; Gene Expression; Genes; Genetic; Goals; Health; Histology; Histone H2A; Histones; Human; Immune System Diseases; In Vitro; Injections; Intra-Articular Injections; Kinetics; Knee; Knee Osteoarthritis; Lead; Link; Luciferases; Lysine; Maintenance; Measures; Mediating; Mesenchymal Stem Cells; Microarray Analysis; Mitochondria; Modeling; Musculoskeletal Diseases; Natural regeneration; Obesity; Operative Surgical Procedures; Osteoporosis; Pathology; Patients; Peptide Hydrolases; Permeability; Pharmaceutical Preparations; Pharmacodynamics; Phase; Physiological; Plasma; Population; Presenile Alzheimer Dementia; Prevalence; Proliferation Marker; Property; RNA marker; Rattus; Recombinants; Regulation; Role; Safety; Series; Site; Small Business Innovation Research Grant; Small Interfering RNA; Solubility; Specificity; Stains; Stratification; Synovial Fluid; Testing; Therapeutic Index; Time; Tissues; Toxic effect; Toxicity Tests; Toxicology; Treatment Efficacy; Ubiquitin; Variant; analog; burden of illness; cell regeneration; cytotoxicity; differential expression; drug candidate; drug development; efficacy testing; genetic variant; genomic locus; human tissue; improved functioning; in vivo; innovation; joint destruction; knee replacement arthroplasty; knock-down; lead candidate; lead optimization; lead series; mouse model; novel; osteoarthritis pain; patient biomarkers; patient population; patient stratification; pharmacokinetics and pharmacodynamics; preclinical efficacy; prevent; promoter; response; scaffold; senescence; side effect; small molecule; small molecule inhibitor; stem cell function; stem cell self renewal; stem cells; systemic toxicity; treatment response; vector

The goal of the project is to develop a disease-modifying treatment for Osteoarthritis (OA) by targeting USP16, a chromatin modifier involved in regulation of senescence and stem cell self-renewal. The treatment will consist of an intra-articular injection of a small molecule inhibiting USP16 in patients with moderate OA. USP16 is a deubiquitinase (DUB) enzyme that removes ubiquitin from histone H2A on lysine 119, a critical mark for the maintenance of multiple somatic tissues. Interestingly, triplication of USP16 is associated with Down syndrome (DS), a congenital disorder characterized by triplication of chromosome 21 (HSA21). Patients with DS show signs of accelerated aging, including early-onset Alzheimer’s, immune dysfunction, and osteoporosis. We have previously shown that reducing the levels of USP16 in DS mouse models or human tissues results in improved function of somatic stem cells and reduction in senescence, therefore alleviating the conditions associated with DS. This evidence makes USP16 an attractive target to ameliorate some of the aging-related pathologies. Notably, USP16 expression is highly upregulated in OA chondrocytes and synovial tissues. Moreover, the genetic locus of USP16 contains a SNP strongly associated with familial OA. We found that genetic downregulation of USP16 in patient-derived articular chondrocytes promotes cellular and mitochondrial health and reduces senescence associated markers, like SA-ꞵ-gal and p16Ink4a. Moreover, microarray analyses of OA chondrocytes treated with siRNA targeting USP16 showed an increase in markers of proliferation and collagen deposition, and a reduction of apoptosis and catabolism markers. Furthermore, USP16 knockdown in human bone marrow-derived mesenchymal stem cells promoted differentiation into mature chondrocytes and increased matrix deposition. Using a biochemical assay testing the enzymatic activity of recombinant human USP16, we identified small molecule inhibitors. We validated 19 hits with low IC50 and chose small molecule scaffolds with IC50 between 0.06 μM and 9.4 μM. During Phase I of the project, we will optimize them to increase potency, specificity, and solubility. During Phase II, we will move the two best compound series into lead optimization, followed by preclinical efficacy in OA models and early toxicity testing of the two best lead compounds. We will assess their safety, pharmacokinetics (PK), ability to engage target and modulate chromatin as a pharmacodynamic (PD) measure, and efficacy in preventing or reversing loss of cartilage in a surgical rat OA model, with the goal of establishing a relationship between time on target, dose and efficacy. We will also study the role of the rs6516886 SNP and understand if specific variants of this genomic locus are linked to differential expression of USP16 and different responses to treatment, potentially leading to stratification of the target patient population. The proposed studies will inform subsequent GLP studies to support an IND and clinical trial.

该项目的目标是通过靶向USP16（一种参与衰老和干细胞自我更新调节的染色质修饰剂）开发一种治疗骨关节炎（OA）的疾病修饰疗法。治疗将包括在中度OA患者关节内注射抑制USP16的小分子。USP16是一种去泛素酶（DUB）酶，可从赖氨酸119上的组蛋白H2A中去除泛素，这是维持多个体细胞组织的关键标志。有趣的是，USP16的三倍与唐氏综合症（DS）有关，唐氏综合症是一种以21号染色体三倍（HSA21）为特征的先天性疾病。退行性痴呆患者表现出加速衰老的迹象，包括早发性阿尔茨海默病、免疫功能障碍和骨质疏松症。我们之前的研究表明，降低DS小鼠模型或人体组织中USP16的水平可以改善体细胞干细胞的功能，减少衰老，从而减轻与DS相关的疾病。这一证据使USP16成为改善一些衰老相关病理的有吸引力的靶点。值得注意的是，USP16在OA软骨细胞和滑膜组织中的表达高度上调。此外，USP16的遗传位点包含一个与家族性OA密切相关的SNP。我们发现，患者来源的关节软骨细胞中USP16的遗传下调可促进细胞和线粒体健康，并减少衰老相关标志物，如SA-ꞵ-gal和p16Ink4a。此外，用靶向USP16的siRNA处理的OA软骨细胞的微阵列分析显示，增殖和胶原沉积标志物增加，凋亡和分解代谢标志物减少。此外，在人骨髓源间充质干细胞中，USP16敲低可促进成熟软骨细胞的分化并增加基质沉积。利用生化试验检测重组人USP16的酶活性，我们确定了小分子抑制剂。我们验证了19个低IC50的hit，并选择了IC50在0.06 ~ 9.4 μM之间的小分子支架。在项目的第一阶段，我们将对它们进行优化，以提高效力、特异性和溶解度。在II期，我们将把两个最佳化合物系列推向先导物优化阶段，然后进行OA模型的临床前疗效和早期毒性测试。我们将评估它们的安全性、药代动力学（PK）、作为药效学（PD）指标参与靶点和调节染色质的能力，以及在手术大鼠OA模型中预防或逆转软骨丢失的功效，目的是建立作用时间、剂量和功效之间的关系。我们还将研究rs6516886 SNP的作用，并了解该基因组位点的特定变异是否与USP16的差异表达和对治疗的不同反应有关，从而可能导致目标患者群体的分层。拟议的研究将为后续GLP研究提供信息，以支持IND和临床试验。