Novel Approaches for Read-through of Nonsense Mutations in COL7A1

通读 COL7A1 无义突变的新方法

• 批准号: 9314378
• 负责人: Qiujie Jiang
• 金额: $ 7.8万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-07 至 2018-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9314378
• 关键词: Affect; Alleles; Amino Acids; Biological Assay; Biological Models; Bulla; Cell Culture Techniques; Cell physiology; Cells; Chronic; Cicatrix; Clinical Trials; Collagen; Collagen Type VII; Complication; Connective Tissue Diseases; Development; Disease; Drug Kinetics; Embryo; Epidermolysis Bullosa; Epidermolysis Bullosa Dystrophica; Fibroblasts; Genes; Heritability; Human; In Vitro; Incidence; Individual; Inherited; Intervention; Lead; Length; Mediating; Medical; Membrane; Messenger RNA; Modeling; Mutation; Nonsense Codon; Nonsense Mutation; Patients; Pharmaceutical Preparations; Pharmacologic Substance; Pharmacology; Phenotype; Property; Proteins; Reporting; Risk; Signs and Symptoms; Skin; Squamous cell carcinoma; Suppressor Mutations; System; Terminator Codon; Testing; Toxicology; Transcript; Transfection; Translating; Ulcer; United States; Validation; Zebrafish; amlexanox; design; effective therapy; efficacy testing; experimental study; in vitro testing; in vivo; keratinocyte; knock-down; mRNA Decay; mutant; novel; novel strategies; patient subsets; polypeptide; pre-clinical; premature; public health relevance

 DESCRIPTION (provided by applicant): Dystrophic epidermolysis bullosa (DEB), an inherited connective tissue disease, manifests with blisters, erosions and chronic ulcers in the skin and mucosal membranes. The signs and symptoms of this condition vary widely among affected individuals; the most severe cases involve widespread blistering that can lead to scarring disfigurement and other serious medical problems. Furthermore, as a complication of the chronic skin damage, patients with DEB have an increased risk in development of highly aggressive squamous cell carcinomas. This disease is caused by mutations in the COL7A1 gene, ~10% of them being nonsense mutations. So far there is no effective treatment. The incidence of EB is estimated to be ~1:20,000 implying that there are 30,000-40,000 affected individuals in the United States. Assuming the same global incidence, there are over half a million EB patients in the world. Since approximately 20 percent of the patients have the dystrophic forms, even with ~10% of patients having nonsense mutations in COL7A1, thousands of patients would benefit from a successful strategy of PTC read-through worldwide. This study will test novel pharmaceutical compounds that facilitate read-through of nonsense mutations and counteract nonsense-mediated mRNA decay, thus allowing synthesis of the full-length polypeptide from the mutant allele, with the hypothesis that correction of COL7A1 mutations will counteract their phenotypic consequences. The read-through compounds with antagonistic properties against nonsense-mediated mRNA decay will be tested in vitro in cell cultures with mutant keratinocytes and fibroblasts derived from the skin of patients with DEB as well as in vivo using zebrafish as a platform. Preclinical demonstration of the efficacy of compounds, such as PTC124 and Amlexanox, can be translated quickly to the clinical trials due to the fact that the pharmacokinetics and toxicology profiles of these drugs have already been established.

 描述（由申请人提供）：营养不良性大疱性表皮松解症（DEB）是一种遗传性结缔组织病，表现为皮肤和粘膜出现水疱、糜烂和慢性溃疡。这种病症的体征和症状在受影响的个体中差异很大；严重的情况下会出现广泛的水泡，可能导致疤痕、毁容和其他严重的医疗问题。此外，作为慢性皮肤损伤的并发症，DEB 患者的风险增加。高度侵袭性鳞状细胞癌的发生是由 COL7A1 基因突变引起的，其中约 10% 是无义突变，迄今为止，EB 的发病率估计约为 1:20,000。美国有 30,000-40,000 名受影响者，假设全球发病率相同，那么全世界大约有 20% 的 EB 患者。即使约 10% 的患者存在 COL7A1 无义突变，全球数以千计的患者也将受益于 PTC 通读的成功策略。这项研究将测试促进无义突变通读的新型药物化合物。抵消无义介导的 mRNA 衰减，从而允许从突变等位基因合成全长多肽，假设 COL7A1 突变的校正将抵消其表型后果。通读化合物对无义介导的 mRNA 具有拮抗特性。衰变将在来自 DEB 患者皮肤的突变角质形成细胞和成纤维细胞的体外细胞培养物中进行测试，以及使用斑马鱼作为平台进行体内测试，以证明 PTC124 和 Amlexanox 等化合物的功效。由于这些药物的药代动力学和毒理学特征已经确定，因此可以迅速进入临床试验。