GSK3 beta study in patients with Myotonic Dystrophy 1

强直性肌营养不良患者的 GSK3 beta 研究 1

• 批准号: 10087889
• 负责人: LUBOV T TIMCHENKO
• 金额: $ 41.8万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-01-15 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10087889
• 关键词: 19q; 3' Untranslated Regions; Address; Adult; Affect; Antisense Oligonucleotides; Anxiety; Biochemical; Biological Products; Biopsy; Blood; Blood specimen; CDK4 gene; CUG repeat; Childhood; Chromosomes; Clinical Research; Clinical Trials; Complex; Development; Disease; Family; Fibroblasts; Genes; Goals; Growth; Human; Infant; Knowledge; Left; Length; Link; Mediating; Messenger RNA; Modification; Molecular; Molecular Analysis; Monitor; Multicenter Studies; Mus; Muscle; Muscle Cells; Muscle Fibers; Muscle function; Muscular Atrophy; Myoblasts; Myofibroblast; Myopathy; Myotonia; Myotonic Dystrophy; Myotonic dystrophy type 1; Neuromuscular Diseases; Newborn Infant; Pathologic; Pathology; Pathway interactions; Patients; Penetrance; Phase; Phase I/II Clinical Trial; Phenotype; Phosphotransferases; Pilot Projects; Publishing; RNA Processing; RNA Splicing; RNA-Binding Proteins; Regulation; Severities; Severity of illness; Signal Transduction; Skeletal Muscle; Skin; Solid; Testing; Therapeutic; Time; Treatment outcome; base; clinical development; cohort; cyclin D3; improved; in vivo; inhibitor/antagonist; mouse model; mutant; novel therapeutic intervention; postnatal; prevent; small molecule; therapeutic target

Myotonic Dystrophy type 1 (DM1) is a complex neuro-muscular disease, caused by an expansion of CTG repeats in the 3’ UTR of DMPK gene on the chromosome 19q. The longest CTG expansions affect infants causing congenital DM1 (CDM1). CTG repeats cause DM1 pathology through alterations of several RNA- binding proteins including CUGBP1 and MBNL1. The phase I/II clinical trial, testing the degradation of the mutant DMPK mRNA by antisense oligonucleotide (AON) has been recently completed. Unfortunately, it was found that further modifications of AONs are required to improve their penetrance to skeletal muscle. Therefore, there is an urgent need for development of alternative therapeutic approaches based on small molecules. My lab is working with the development of a novel therapeutic approach for the treatment of CDM1 and DM1 which is based on the correction of RNA processing (including splicing) that is mis-regulated by CUG n-GSK3β-CUGBP1 axis. We found that the activity of CUGBP1 is regulated by GSK3β-cyclin D3-CDK4 pathway and that the mutant CUG repeats alter CUGBP1 activity by the pathological increase of GSK3β kinase. The inhibitors of GSK3 significantly reduce DM1 muscle pathology in a mouse model of DM1 (HSA mice) and improve growth and neuromotor activity in CDM1 mouse model (DMSXL mice). These basic findings created a strong background for the first, the GSK3-based clinical study for adult patients with CDM1. The Phase IIa of this trial with the inhibitor of GSK3 tideglusib (TG) was recently completed by a biopharmaceutical company AMO Pharma with encouraging results. Although the trial is in transition to the Phase II/III in pediatric CDM1, much more mechanistic studies, including molecular analysis of the GSK3β-CUGBP1 pathway in human patients’ materials, are needed to further support the clinical trial using TG. My application will examine the GSK3β-CUGBP1 pathway in muscle biopsies, myofibrobasts and blood samples from DM1 and CDM1 patients with variable disease severity (Aim 1). We will also study if GSK3β was corrected in CDM1 patients treated with TG. We will determine if the treatments with TG recover MBNL1 activity correcting global splicing abnormalities in DM1 (Aim 2). All pathways affected by TG treatments will be defined. One more critical issue will be addressed in my application. We recently found that the TG-treatments of DM1 myoblasts and fibroblasts derived from patients with 200-400 CTG repeats reduce the levels of the mutant DMPK mRNA. We propose to examine if TG improves degradation of the mutant DMPK regardless of the length of CTG expansions (Aim 3). If TG improves the degradation of the mutant DMPK mRNA in DM1 and CDM1 myoblasts and fibroblasts with long expansions, the inhibitors of GSK3 will represent small molecules targeting the prime cause of CDM1 and DM1. The obtained knowledge will be critical for the further development of clinical trials of CDM1 and DM1 that are based on the correction of GSK3β.

Myotonic Dypy 1型（DM1）是一种复杂的神经肌肉疾病，由CTG的扩张引起 DMPK基因的3’UTR在19q染色体上的3’UTR中重复。最长的CTG扩展会影响婴儿 引起先天性DM1（CDM1）。 CTG重复通过改变几个RNA- 结合蛋白包括CUGBP1和MBNL1。 I/II期临床试验，测试了降解 反义寡核苷酸（AON）最近完成了突变的DMPK mRNA。不幸的是，是 发现需要进一步的AONS修改以改善其对骨骼肌的渗透率。 因此，迫切需要开发基于小的替代治疗方法 分子。我的实验室正在开发一种新型治疗方法来治疗CDM1 和DM1基于校正RNA处理（包括剪接）的校正，而CUG错误地调节了 N-GSK3β-CUGBP1轴。我们发现CUGBP1的活性受GSK3β-Cyclin D3-CDK4的调节 途径，突变库重复通过GSK3β的病理增加改变CUGBP1活性 激酶。 GSK3的抑制剂显着降低了DM1小鼠模型（HSA）的DM1肌肉病理学 小鼠）并改善CDM1小鼠模型（DMSXL小鼠）中的生长和神经运动活性。这些基本发现 针对CDM1患者的第一个基于GSK3的临床研究创造了强大的背景。这 该试验的IIA使用GSK3 Tideglusib（TG）的抑制剂最近由生物制药完成 公司Amo Pharma具有令人鼓舞的结果。尽管该试验正在过渡到小儿II/III期 CDM1，更多的机械研究，包括对GSK3β-CUGBP1途径的分子分析 需要使用TG进一步支持临床试验的人类患者的材料。我的申请将检查 来自DM1和CDM1的肌肉活检，肌动纤维和血液样本的GSK3β-CUGBP1途径 疾病严重程度可变的患者（AIM 1）。我们还将研究CDM1患者是否校正GSK3β 用TG处理。我们将确定TG的处理是否恢复MBNL1活动，以纠正全局剪接 DM1异常（AIM 2）。将定义受TG治疗影响的所有途径。另一个关键问题 将在我的应用程序中解决。最近，我们发现DM1成肌细胞的TG处理和 来自200-400 CTG重复序列的患者得出的成纤维细胞降低了突变体DMPK mRNA的水平。我们 提议检查TG是否可以改善突变体DMPK的降解，而不管CTG的长度如何 扩展（目标3）。如果TG改善了DM1和CDM1成肌细胞中突变体DMPK mRNA的降解 和具有长膨胀的成纤维细胞，GSK3的抑制剂将代表针对质量的小分子 CDM1和DM1的原因。获得的知识对于进一步发展的临床试验至关重要 基于GSK3β校正的CDM1和DM1。