Robust-to-fragile transitions of a phase-separated mitotic organelle in triple-negative breast cancer

三阴性乳腺癌相分离有丝分裂细胞器的稳健到脆弱的转变

• 批准号: 10703476
• 负责人: P. TODD STUKENBERG
• 金额: $ 35.8万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-12 至 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10703476
• 关键词: Alleles; Aneuploid Cells; Aneuploidy; Animals; BIRC5 gene; Behavior; Binding; Biochemical Reaction; Biochemistry; Biological Models; Buffers; Bypass; Cells; Centromere; Chromosomal Instability; Chromosome Segregation; Chromosome abnormality; Chromosomes; Chronic; Clinical; Clinical Trials; Clonal Expansion; Complex; Differential Equation; Diffusion; Disease; ERBB2 gene; Engineering; Event; Evolution; Exhibits; FOXM1 gene; Feedback; Genes; Gland; Goals; Image; In Situ; Kinetochores; Lesion; Light; Link; Liquid substance; Loss of Heterozygosity; Malignant Neoplasms; Mammary Neoplasms; Mammary gland; Mediator; Metaphase; Microscopy; Microtubules; Mitosis; Mitotic; Mitotic Chromosome; Mitotic spindle; Mitotic/Spindle Checkpoint; Modeling; Mutate; Oncogenic; Operative Surgical Procedures; Organelles; Organoids; Pathology; Pathway interactions; Patients; Phase; Phenotype; Physical condensation; Predisposition; Primary Neoplasm; Productivity; Proteins; Regulation; Rodent; Sampling; Signal Transduction; Sister Chromatid; Solid Neoplasm; Stress; System; Systems Analysis; TP53 gene; Testing; Therapeutic; Tissues; Translating; Visualization; Work; aurora B kinase; chromosome missegregation; clinical diagnostics; diagnostic assay; genome integrity; histone modification; in vivo; inner centromere protein; kinase inhibitor; malignant breast neoplasm; mammary; micronucleus; mosaic; mosaic analysis; multidisciplinary; mutant; novel; pharmacologic; predictive modeling; recruit; repaired; segregation; sensor; small molecule inhibitor; transcription factor; triple negative cancer; triple-negative invasive breast carcinoma; tumor; tumorigenesis; upstream kinase; virtual

PROJECT ABSTRACT/SUMMARY Aneuploidy and loss of heterozygosity are highly prevalent chromosome aberrations caused by sister- chromatid segregation errors during mitosis. Aneuploidy is especially common in triple-negative breast cancers, where outgrowth of aneuploid cells is permitted by the near-universal loss of TP53 that normally surveils genomic integrity. Prior work from our team has connected the aneuploid phenotype in breast cancer to network-level abundance changes in genes induced by mitotic transcription factors, which are chronically elevated in tumors. The target genes of these transcription factors reside upstream and downstream of the chromosome passenger complex (CPC), a four-protein sensor of proper spindle assembly and a mediator of repair. The CPC must localize to the inner centromere and auto-activate when microtubules are incorrectly attached. We recently found that the CPC accumulates during metaphase to a critical concentration causing it to phase separate as a liquid condensate. CPC phase separation likely confers robustness of function, yet cancers manage to bypass this checkpoint by changing the abundance of multiple regulators and effectors that together cause cells to enter a state of chromosome instability. Our objective is to unravel how the complex abundance imbalances of network regulators found in tumors stress the robust localization of the CPC to the inner centromere and generate chromosome instability in breast cancers or precursor lesions. The leading hypothesis is that phase-separated CPC acts as a “phenotypic capacitor” during mitosis by buffering small to moderate imbalances (storage) and unleashing dramatic rearrangements when a threshold imbalance is reached (discharge). We will test this hypothesis using biochemical reaction-diffusion models of spatially regulated CPC phase separation, which will be tailored to primary mammary organoids derived from a mosaic GEMM of triple-negative mammary cancer and extended to clinical samples through standard diagnostic assays. The specific aims are to 1) develop and validate a spatial systems model of CPC recruitment that isolates phase separation and predicts critical network imbalances in cancer-predisposed mammary organoids; 2) test the instability-generating potential of critical network imbalances by quantitatively perturbing triple- negative mammary premalignancies in vivo; and 3) leverage routine clinical diagnostics to predict druggable chromosomal instability signatures in any primary breast cancer. Patient-specific, systems-level models of aneuploidy susceptibility will nominate kinase inhibitors in the network that are predicted to shift cells from robust to fragile states of segregation fidelity.

项目摘要/总结 非整倍体和杂合性丢失是由姐妹染色体引起的高度普遍的染色体畸变。 有丝分裂时染色单体分离错误。非整倍体在三阴性乳腺癌中尤其常见。 癌症，其中非整倍体细胞的生长是由TP 53的几乎普遍的损失所允许的， 监控基因组的完整性我们团队之前的工作已经将乳腺癌中的非整倍体表型联系起来 到有丝分裂转录因子诱导的基因网络水平丰度变化，这些转录因子是慢性的 在肿瘤中升高。这些转录因子的靶基因位于转录因子的上游和下游。 染色体乘客复合物（CPC），一个四蛋白传感器正确的纺锤体组装和调解人， 修复. CPC必须定位于内部着丝粒，并在微管错误定位时自动激活。 附我们最近发现，CPC在中期积累到临界浓度， 以液态冷凝物的形式进行相分离。CPC相分离可能赋予功能的鲁棒性，但 癌症通过改变多种调节因子和效应因子的丰度来绕过这个检查点， 共同导致细胞进入染色体不稳定状态。我们的目标是解开 在肿瘤中发现的网络调节因子的丰度不平衡强调了CPC在肿瘤中的强大定位。 在乳腺癌或癌前病变中产生染色体不稳定性。领导 有一种假说认为相分离CPC在有丝分裂过程中作为一种“表型电容器”， 适度的不平衡（存储）和释放戏剧性的重组时，阈值不平衡是 到达（放电）。我们将使用空间上的生物化学反应扩散模型来检验这一假设。 受调节的CPC相分离，其将针对源自镶嵌的原发性乳腺类器官进行定制 三阴性乳腺癌的GEMM，并通过标准诊断扩展到临床样本 测定。具体目标是：1）开发和验证CPC招聘的空间系统模型， 分离相分离并预测癌症易感乳腺类器官中的关键网络失衡; 2)通过定量扰动三重网络， 体内阴性乳腺癌前病变;和3）利用常规临床诊断来预测可药物治疗的 任何原发性乳腺癌的染色体不稳定性特征。特定于患者的系统级模型 非整倍体易感性将提名网络中的激酶抑制剂，预计将细胞从 对分离保真度的脆弱状态具有鲁棒性。