Investigating PolQ-mediated alternative NHEJ in breast cancer

研究乳腺癌中 PolQ 介导的替代 NHEJ

• 批准号: 10379672
• 负责人: Agnel Sfeir
• 金额: $ 22.46万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-10 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10379672
• 关键词: Affect; BRCA1 gene; BRCA2 gene; Biochemical; Biotin; Breast Cancer Model; Cancer-Predisposing Gene; Cells; Characteristics; Chemotherapy and/or radiation; Chromosomal Rearrangement; Chromosome abnormality; Chromosomes; Cicatrix; Cisplatin; Clinical; DNA Damage; DNA Double Strand Break; DNA Repair; DNA Repair Pathway; Data; Defect; Development; Disease Progression; Double Strand Break Repair; Enzymes; Evolution; Genes; Genetic; Genetic Recombination; Genomic Instability; Genomics; Goals; Human; Ionizing radiation; Knockout Mice; Ligase; Malignant Neoplasms; Malignant neoplasm of ovary; Mammalian Cell; Mammary Neoplasms; Mediating; Molecular; Mus; Mutate; Mutation; Nonhomologous DNA End Joining; Outcome; Pathway interactions; Patients; Phenotype; Polymerase; Predisposition; Proteome; Proteomics; Radiation therapy; Relapse; Resistance; Role; Shapes; Signal Transduction; Site; Source; System; Testing; Therapeutic Agents; Treatment-Associated Neoplasms; Work; base; brca gene; breast cancer progression; cancer cell; cancer genome; cancer therapy; carcinogenesis; chemotherapy; cohort; effective therapy; established cell line; experimental study; genetic makeup; genome integrity; genome sequencing; genomic signature; homologous recombination; improved; in vivo; inhibitor/antagonist; insight; malignant breast neoplasm; mouse model; neoplastic cell; novel; novel therapeutics; ovarian neoplasm; recruit; repaired; treatment strategy; tumor; tumor behavior; tumor initiation; tumor progression; tumorigenesis; whole genome

Chromosomal rearrangements are a hallmark of cancer cells and constitute a major pathway by which genes that affect tumor initiation and progression become mutated. Such aberrancies can result from defects in double-stranded break (DSB) repair. There are three major pathways of DNA repair in mammalian cells – the well-studied homology recombination (HR) and non-homologous end joining (NHEJ) pathways, and the poorly characterized, yet highly error-prone alt-NHEJ (alternative-NHEJ) pathway. Genetic rearrangements consistent with alt-NHEJ have been noted both in spontaneous and therapy-related tumors. In this proposal we will focus on polymerase theta (Polθ), a low-fidelity enzyme that we recently identified as a key factor that mediates DSB repair by alt-NHEJ. Given that HR-defective tumors are “addicted” to repairing DSBs via the alt-NHEJ pathway, we hypothesize that the mutagenic activity of Polθ help establish a genomic landscape that is conducive for aggressive tumor behavior. Additionally, we predict that deleting Polθ in tumors with mutations in the breast cancer susceptibility (BRCA) genes will sensitize cells to DNA damage- inducing therapeutic agents, including radiation therapy, cisplatin and PARP inhibitors. In the second aim, we will investigate the impact of ATM and PARP1 on Polθ is recruited to break sites and how the polymerase modulates damage sites to promote erroneous repair. In addition, we will pursue a proteomic-based approach to highlight the full spectrum of molecular players involved in alt-NHEJ. Ultimately, a full understanding of the mechanistic basis of alt-NHEJ will provide a better understanding of the source of genomic instability during the course of malignancy and guide more effective treatment strategies for the increasing number of patients with HR mutated tumors.

染色体重排是癌细胞的标志，构成了主要途径 哪些影响肿瘤倡议和进展的基因被突变。这样的异常可以 双链断裂（DSB）修复中的缺陷导致。 DNA有三个主要途径 哺乳动物细胞的修复 - 研究良好的同源重组（HR）和非理论 结束加入（NHEJ）途径，并且特征较差，但高度易于错误的Alt-Nhej （替代nhej）途径。已经注意到与Alt-Nhej一致的遗传重排 在赞助和治疗相关的肿瘤中。在此提案中，我们将重点放在聚合酶theta上 （polθ），一种低保真酶，我们最近将其确定为介导DSB修复的关键因素 alt-nhej。鉴于HR缺陷肿瘤被“上瘾”以通过Alt-Nhej修复DSB 途径，我们假设Polθ的诱变活性有助于建立基因组景观 这是侵袭性肿瘤行为的导电。此外，我们预测肿瘤中的polθ删除 随着乳腺癌易感性（BRCA）基因的突变会感知细胞对DNA损伤 - 诱导的治疗剂，包括放射治疗，顺铂和PARP抑制剂。在 第二个目的，我们将调查ATM和PARP1对POLθ的影响，以打破站点 以及聚合酶如何调节损伤部位以促进错误修复。此外，我们将 追求一种基于蛋白质组学的方法，以突出参与的全部分子参与者 alt-nhej。最终，对Alt-Nhej的机械基础的充分理解将提供更好的 了解恶性肿瘤过程中基因组不稳定性的来源，并指导更多 HR突变肿瘤患者数量增加的有效治疗策略。