Anti-cancer therapeutic approaches for targeting the ALT telomere maintenance mechanism

针对 ALT 端粒维持机制的抗癌治疗方法

• 批准号: 10054845
• 负责人: Jaewon Min
• 金额: $ 19.25万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10054845
• 关键词: 3-Dimensional; ATP phosphohydrolase; Acute Promyelocytic Leukemia; Alternative Therapies; Applications Grants; Biological Assay; Biophysics; CRISPR screen; Cancer cell line; Candidate Disease Gene; Cell Culture System; Cell Culture Techniques; Cell Line; Cells; Cellular biology; Clinical Trials; Cluster Analysis; Complementary DNA; DNA Repair Pathway; DNA biosynthesis; Diagnosis; Endocrine Gland Neoplasms; Engineering; Fluorescent in Situ Hybridization; Future; Gel; Generations; Genes; Glioblastoma; Glioma; Goals; Human; K22 Award; Lead; Malignant Childhood Neoplasm; Malignant Neoplasms; Mediating; Mesenchymal; Mitotic; Modeling; Molecular; Molecular Chaperones; Molecular Target; Neuroblastoma; Normal tissue morphology; Patients; Phase; Phenotype; Polymerase; Positioning Attribute; Post-Translational Protein Processing; Process; Proliferating; Proteins; Proteome; Proteomics; Publications; Publishing; Reaction; Research; Research Institute; Research Personnel; Series; Sumoylation Pathway; Suppressor Genes; System; Techniques; Telomerase; Telomerase inhibition; Telomere Maintenance; Telomere Pathway; Testing; Therapeutic; Toxic effect; Training; Ubiquitin; Ubiquitination; United States; Universities; Work; Xenograft Model; Xenograft procedure; alternative treatment; anti-cancer therapeutic; base; cancer cell; career; early childhood; experimental study; genome wide screen; genome-wide; improved; in vivo; molecular targeted therapies; mutant; new therapeutic target; novel; novel therapeutics; osteosarcoma; overexpression; patient derived xenograft model; personalized cancer therapy; professor; reconstitution; sarcoma; scaffold; screening; segregation; small hairpin RNA; small molecule inhibitor; stable cell line; stem-like cell; subcutaneous; telomere; therapeutic target; tumor; tumor DNA; tumor growth; tumorigenesis; ubiquitin-protein ligase

Project Summary/Abstract During tumorigenesis, cancer cells need to acquire a telomere maintenance mechanism to proliferate indefinitely. Cancers of mesenchymal origin (such as sarcomas, endocrine tumors, glioblastoma, and some early childhood cancers), frequently acquire a telomerase-independent telomere maintenance mechanism, which has been termed Alternative Lengthening of Telomeres (ALT). Moreover, it has been shown that telomerase inhibition in telomerase positive human cancer cells can engage the ALT pathway. Although ALT cancers can be diagnosed by telomere fluorescence in situ hybridization (FISH) of tumor sections, and by using the C-circle assay (phi29 polymerase reaction) of tumor DNA, currently there are no therapeutic targets or clinical trials for ALT tumor treatment. Therefore, identification of potential therapeutic targets for ALT tumors may significantly improve the options for patients with ALT cancers by identifying and exploitering unique ALT cancer vulnerabilities. Ultimately, this should lead to personalized cancer treatment based on ALT status. From my recent studies, I found that the molecular mechanism of ALT is initiated by excessive and persistent clustering of telomeres in PML bodies. I have been further investigating that these processes are mediated by a series of post-translational modifications and segregation: ubiquitination by SUMO-targeted ubiquitination E3 ligase (RNF4), and segregation by ubiquitin- selective chaperone/AAA ATPase (p97; also known as VCP). In aim 1, I will further dissect the mechanism of RNF4 and p97 in ALT pathway and validate the therapeutic window of opportunity to inhibit the RNF4-p97 axis as an effective anti-ALT cancer strategy. One of the hallmarks of ALT cancers is the clustering of large amounts of telomeres in promyelocytic leukemia (PML) bodies. I have developed a biophysical system that reconstitutes PML bodies from minimal components and generates telomere clustering, thus mimicking ALT-associated PML bodies (APBs) in vivo. In aim 2, I will further engineer the biophysical system mimicking ALT cancer phenotype and apply this ALT model to proteomics and candidate gene screenings to identify novel therapeutic targets for ALT cancer. My primary career goal is to obtain an assistant professor position at a R1 university or research institute in the United States. My long-term career goal is to become an independent investigator and leader in the field of cancer cell biology. Training under a K22 award will serve as the basis for the future direction of my research, and the resulting publications will support my transition toward independence and prepare me to submit additional grant applications including R01s. The results that I obtain from Aim 1 and Aim 2 will allow me to further investigate the molecular mechanisms of the ALT pathway to identify new molecular targets and novel therapies for ALT cancers that are not currently available.

项目摘要/摘要 在肿瘤发生过程中，癌细胞需要获得无限期增殖的端粒维持机制。 间质起源的癌症（例如肉瘤，内分泌肿瘤，胶质母细胞瘤和一些幼儿 癌症），经常获得与端粒酶无关的端粒维护机制， 称为端粒的替代延长（ALT）。此外，已经表明端粒酶抑制 端粒酶阳性人类癌细胞可以参与ALT途径。虽然可以诊断出Alt Cancer 肿瘤切片的原位杂交（FISH），并使用c-Circle分析（PHI29） 肿瘤DNA的聚合酶反应），目前尚无治疗靶标或ALT肿瘤的临床试验 治疗。因此，鉴定ALT肿瘤的潜在治疗靶标可能会显着改善 通过识别和利用独特的ALT癌症脆弱性，为患有ALT癌的患者提供的选择。最终， 这应该导致基于ALT状态的个性化癌症治疗。从最近的研究中，我发现 ALT的分子机制是通过PML体中端粒的过度和持续聚类引发的。我 已经进一步研究了这些过程是由一系列翻译后修改介导的 和隔离：通过靶向泛素化的泛素化E3连接酶（RNF4），以及通过泛素 - 选择性伴侣/AAA ATPase（P97；也称为VCP）。在AIM 1中，我将进一步剖析 ALT途径中的RNF4和P97，并验证抑制RNF4-P97轴的治疗机会窗口 作为有效的抗alt癌策略。 ALT癌的标志之一是大量的聚类 临床细胞白血病（PML）体内的端粒。我已经开发了一个生物物理系统来重构 来自最小成分的PML体并产生端粒聚类，从而模仿与Alt相关的PML 身体（APB）在体内。在AIM 2中，我将进一步设计模仿ALT癌表型的生物物理系统 并将此ALT模型应用于蛋白质组学和候选基因筛选，以确定新的治疗靶标 Alt Cancer。我的主要职业目标是在R1大学或研究中获得助理教授职位 美国研究所。我的长期职业目标是成为独立的调查员和领导者 癌细胞生物学领域。根据K22奖的培训将作为我未来指导的基础 研究，由此产生的出版物将支持我向独立过渡，并为我做好准备 提交包括R01在内的其他赠款申请。我从AIM 1和AIM 2获得的结果将使我 进一步研究ALT途径的分子机制，以鉴定新的分子靶标和新的分子机制 当前尚不可用的ALT癌的疗法。