Nonsense Readthrough: a Therapeutic Approach to Inherited Vascular Disorders

 描述(由申请人提供) 这项研究的目的是对无意义阅读作为一种潜在的治疗骨形态发生蛋白信号通路突变引起的遗传性血管疾病的潜在疗法进行临床前评估。我们将评估两种具有互补特性的药物。阿塔鲁仑是FDA指定的孤儿药物，正在进行两种遗传性疾病的3期试验。它促进无义突变的通读，而不影响mRNA转录水平，并且对UGA终止密码子最有效。氨来昔诺是一种抗过敏药物，也可以促进无稽之谈的通读，但这是通过抑制无稽之谈介导的mRNA衰退来实现的。关于其密码子特异性的信息有限，但它可能比阿托洛林对UAG密码子表现出更高的活性。我们将测试这两种化合物对两种不同但相关的血管疾病背后的突变的比较效果：遗传性出血性毛细血管扩张症(HHT)和肺动脉高压(PAH)。这两种疾病的突变谱是互补的，在PAH中以UGA密码子为主，而在HHT中UAG/UAA突变更常见。PAH是一种威胁生命和不可治愈的疾病，影响肺血管，迫切需要新的治疗方法来解决导致血管重塑的潜在分子变化。HHT影响全身血管，与肺和脑的动静脉畸形相关的发病率很高。少数情况下，高血压病患者也可能发展为PAH。我们将利用(A)我们开发的用于测量通读效率并对所产生的蛋白质产品进行测序的新型双标签体外报告结构，(B)具有明确基因突变的患者来源的内皮细胞来研究细胞信号的功能恢复，以及(C)用于体内测试的具有无义突变的新型敲入小鼠模型。仅在美国，纠正无义突变就可以使6000-12000名HHT患者和多达1000名PAH患者受益。这项研究的成功完成将确立这种方法在体内的有效性，并确定最有可能做出反应的患者亚组。此外，我们开发的用于测量通读效率和所结合氨基酸的性质的新型双标签报告将适用于许多其他遗传性疾病。这项研究的结果可能会迅速转化为干预性人体试验，并为个性化治疗遗传性血管疾病的方法铺平道路。

 DESCRIPTION (provided by applicant) The goal of this study is a pre-clinical evaluation of nonsense readthrough as a potential therapy for inherited vascular disorders caused by mutations in the bone morphogenetic protein signaling pathway. We will evaluate two drugs with complementary properties. Ataluren is a FDA-designated orphan drug in phase 3 trials for two genetic disorders. It promotes readthrough of nonsense mutations without affecting the level of mRNA transcript and is most effective against UGA stop codons. Amlexanox is an anti-allergy drug that also promotes nonsense readthrough, but does so by inhibiting nonsense- mediated mRNA decay. Information on its codon specificity is limited, but it may show higher activity than ataluren against UAG codons. We will test the comparative effects of these two compounds on mutations that underlie two distinct but related vascular disorders: hereditary hemorrhagic telangiectasia (HHT) and pulmonary arterial hypertension (PAH). The mutation spectrum in these two disorders in complementary, with UGA codons predominating in PAH, whereas UAG/UAA mutations are more common in HHT. PAH is a life-threatening and incurable disease affecting the lung vasculature that is in desperate need of new therapies to tackle the underlying molecular changes that drive vascular remodeling. HHT affects blood vessels throughout the body and has high morbidity associated with arteriovenous malformations in the lungs and brain. Rarely, HHT patients may also develop PAH. We will utilize a combination of (a) a novel dual-tag in vitro reporter construct that we have developed to measure readthrough efficiency and sequence the resulting protein product, (b) patient-derived endothelial cells with defined genetic mutations to study functional restoration of cell signaling and (c) a novel knock-in mouse model with a nonsense mutation for in vivo testing. In the US alone, correction of nonsense mutations could benefit 6000-12,000 people affected with HHT and up to 1000 with PAH. Successful completion of this study will establish the effectiveness of this approach in vivo and define the sub-groups o patients most likely to respond. In addition, the novel dual-tag reporter that we have developed to measure both the efficiency of readthrough and the nature of the amino acid that is incorporated will be generalizable to many other genetic disorders The results of this study could translate rapidly to interventional human trials and pave the way for personalized approaches to therapy for genetic vascular diseases.