Cohesin gene mutations in tumorigenesis

肿瘤发生中的粘连蛋白基因突变

• 批准号: 9349394
• 负责人: David A. Solomon
• 金额: $ 39.63万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-19 至 2020-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9349394
• 关键词: Acute Myelocytic Leukemia; Address; Affect; Aneuploid Cells; Aneuploidy; Antibodies; Architecture; Automobile Driving; Biology; Bone Marrow Cells; Bone neoplasms; Bruck-de Lange syndrome; CRISPR interference; CSPG6 gene; Cancer Biology; Cancer cell line; Cell Line; Cell Nucleus; Cell Separation; Cell division; Cell physiology; Cells; ChIP-seq; Chromatin; Chromatin Structure; Chromosomal Instability; Chromosome Segregation; Clinical; Complex; Constitutional; Coupled; Cytogenetics; DNA Damage; DNA Repair; DNA biosynthesis; Development; Diet; Diploidy; Disease; Embryo; Embryonic Development; Engineering; Ensure; Enterobacteria phage P1 Cre recombinase; Epithelium; Event; Ewings sarcoma; Exons; FGFR3 gene; Face; Functional disorder; Gene Expression Regulation; Gene Mutation; Gene Silencing; Genes; Genetic; Genetic Recombination; Genetic Transcription; Germ-Line Mutation; Glial Fibrillary Acidic Protein; Glioblastoma; Gliomagenesis; Growth; Hematopoietic; Hematopoietic Neoplasms; Histologic; Human; Interferons; Knock-out; Knockout Mice; Limb structure; Malignant Neoplasms; Malignant neoplasm of brain; Malignant neoplasm of urinary bladder; Mediating; Mental Retardation; Methods; Mitosis; Molecular; Monitor; Multiprotein Complexes; Mus; Mutation; Neoplasms; Neuraxis; Neuroglia; Nucleic Acid Regulatory Sequences; Oncogenic; Other Genetics; Outcome; Pathogenesis; Patients; Phenotype; Positioning Attribute; Radiation; Regimen; Regulation; Research; Role; Series; Sister Chromatid; Site; Study models; Subgroup; Tamoxifen; Testing; Therapeutic; Transitional Cell Carcinoma; Tumor Suppressor Genes; Urinary tract; Yeasts; base; cancer cell; cancer genome; cancer therapy; carcinogenesis; chromatin immunoprecipitation; cohesin; cohesion; daughter cell; deep sequencing; design; effective therapy; exome; experimental study; gene product; homologous recombination; killings; mouse development; mutant; promoter; public health relevance; pup; radiation response; repaired; response; tumor; tumorigenesis; vector

 DESCRIPTION (provided by applicant): One of the major challenges in the treatment of cancer is the large variety of oncogenic alterations within the cancer genome affecting many different cellular processes. As such, effective therapy will likely be based on the specific genetic alterations present in each patient's tumor rather than a single generalized therapy regimen. I recently discovered frequent inactivating mutations of genes including STAG2 that encode the multi- protein cohesin complex in several tumors including glioblastoma, urothelial carcinoma, Ewing sarcoma, and acute myeloid leukemia (AML), which define molecular subgroups of these tumors with distinct clinical outcomes. The cohesin complex is responsible for sister chromatid cohesion following DNA replication and helps ensure faithful chromosome segregation during mitosis, but has also been implicated in additional cellular processes such as regulation of chromatin architecture and gene transcription. My studies in glioblastoma demonstrated that STAG2 mutations were a direct cause of chromosomal instability and aneuploidy; however, cohesin gene alterations in urothelial carcinoma and AML have been identified primarily in near-diploid tumors, suggesting alternative mechanisms by which cohesin inactivation drives oncogenesis. Using a newly generated conditional STAG2 knockout mouse and previously generated isogenic sets of STAG2 proficient and deficient cancer cell lines, I have designed a series of experiments to determine the function of STAG2 during mouse development and tumorigenesis and identify therapeutic methods to selectively target cancer cells harboring cohesin gene mutations. In the first aim, I will determine the impact on murine development of inducing STAG2 knockout starting in embryogenesis using both histologic and cellular characterization. In the second aim, I will determine the function of STAG2 in urothelial carcinogenesis and gliomagenesis by inducing specific knockout of STAG2 within the epithelium of the urinary tract and glial cells of the central nervous system. The proposed studies will prove if STAG2 is a bona fide tumor suppressor gene, identify cooperating genetic alterations, and determine whether chromosomal instability is a driving oncogenic mechanism. In the third aim, I will determine possible alternative mechanisms by which STAG2 inactivation contributes to tumor development. I will perform experiments to assess the hypothesis that cohesin localizes to regulatory regions of genes that control cellular differentiation and that STAG2 inactivation disrupts cohesin- mediated regulation of these genes controlling differentiation. In the final aim,I will use isogenic sets of STAG2 proficient and deficient cells to determine the role of cohesin in DNA damage repair and the response to radiation and specific DNA damaging agents, as well as perform a CRISPRi-based negative selection screen in order to identify gene products that are required (i.e. synthetically lethal) in the presence STAG2 inactivation. Together, these experiments will determine the function of STAG2 in mouse development and tumorigenesis and identify therapeutic vulnerabilities in the many cancers harboring cohesin gene alterations.

 描述（由适用提供）：癌症治疗的主要挑战之一是癌症基因组中影响许多不同细胞过程的多种致癌改变。因此，有效的治疗可能基于每个患者肿瘤中存在的特定遗传改变，而不是单一的普遍治疗方案。我最近发现，在包括胶质母细胞瘤，尿路上皮癌，ewing肉瘤和急性髓样白血病（AML）的几种肿瘤中编码多种蛋白质粘着蛋白复合物的基因的突变，这些肿瘤构成了这些肿瘤的分子亚组，这些肿瘤是具有不同的临床库存的分子亚组。粘蛋白复合物是DNA复制后姐妹染色质凝聚的原因，并有助于确保有丝分裂过程中忠实的染色体分离，但也已在其他细胞过程中浸没了诸如染色质结构和基因转录等其他细胞过程。我对胶质母细胞瘤的研究表明，Stag2突变是染色体不稳定性和非整倍性的直接原因。然而，在近二倍体肿瘤中已经鉴定出尿路上皮癌和AML的粘着蛋白基因改变，这表明粘合素失活驱动的替代机制。我使用新生成的有条件的Stag2基因敲除小鼠，并先前生成的STAG2熟练和确定的癌细胞系的等源性集，我设计了一系列实验，以确定小鼠发育和肿瘤发生过程中Stag2的功能，并确定具有选择性靶向具有凝聚蛋白基因突变的癌细胞的治疗方法。在第一个目标中，我将使用组织学和细胞表征来确定诱导的stag2敲除鼠的发展的影响。在第二个目标中，我将通过诱导中枢神经系统的尿路和神经胶质细胞中的stag2的特定敲除，确定Stag2在尿路上皮癌发生和神经胶作用中的功能。拟议的研究将证明 如果Stag2是一种真正的肿瘤抑制基因，请确定遗传改变，并确定染色体不稳定性是否是驱动致癌机制。在第三个目的中，我将确定Stag2失活有助于肿瘤发展的可能替代机制。我将进行实验，以评估粘素定位于控制细胞分化的基因的调节区域的假设，而Stag2失活会破坏控制分化的这些基因的凝聚素介导的调节。在最终目的中，我将使用STAG2熟练且缺陷的细胞的等生源集来确定粘蛋白在DNA损伤修复以及对辐射和特定DNA损伤剂的反应中的作用，并在存在Stag2 Inactivation中识别所需的基因基因，以识别所需的基因产物（即合成的Lethal）。总之，这些实验将确定Stag2在小鼠发育和肿瘤发生中的功能，并确定许多具有粘蛋白基因改变的癌症的治疗脆弱性。