Targeting Tumor Initiating Cell in Undifferentiated Pleomorphic Sarcoma

靶向未分化多形性肉瘤中的肿瘤起始细胞

• 批准号: 9120229
• 负责人: Benjamin Aaron Alman
• 金额: $ 43.56万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9120229
• 关键词: Ablation; Accounting; Adenoviruses; Aftercare; Alleles; Allografting; Antibodies; Automobile Driving; Biological Assay; CSPG4 gene; Cell Fraction; Cell surface; Cells; Characteristics; Chondroitin Sulfate Proteoglycan; Clear Cell; Color; Data; Deletion Mutation; Development; Diphtheria Toxin; Disease; Erinaceidae; Exhibits; Experimental Models; Gene Expression; Genetic Recombination; Growth; Human; Immune; Immunodeficient Mouse; Immunotherapy; In Situ; Individual; Infection; Intramuscular Injections; Label; Lead; Malignant Fibrous Histiocytoma; Mediating; Molecular Profiling; Mus; Mutant Strains Mice; Mutation; Neoplasm Metastasis; Oncogenes; Oncogenic; Outcome; Patients; Population; Population Dynamics; Proteins; Radiosurgery; Recurrence; Resistance; Role; Side; Signal Pathway; Soft tissue sarcoma; Stable Populations; TP53 gene; Tamoxifen; Testing; Time; Transgenic Mice; Transplantation; Undifferentiated; Work; Xenograft procedure; base; chemotherapy; conventional therapy; daughter cell; effective therapy; innovation; insight; knock-down; mouse Cre recombinase; mouse model; neoplastic cell; notch protein; novel; novel strategies; novel therapeutic intervention; outcome forecast; prevent; public health relevance; recombinase; sarcoma; self-renewal; small hairpin RNA; therapeutic target; tumor; tumor eradication; tumor growth; tumor progression

DESCRIPTION (provided by applicant): Undifferentiated pleomorphic sarcoma (UPS) is a soft tissue sarcoma, with one of the worst prognosis. We will build on our discovery that UPS contains a small subpopulation of tumor initiating cells (TICs) that are enhanced for the ability t form tumors when transplanted into immune-deficient mice. Our proof of principle data showed that therapeutically targeting signaling pathways activated in the TIC population inhibits growth in UPS tumors established as xenografts in mice. In our preliminary data, we identified the chondroitin sulfate proteoglycan, NG2, as expressed in the TIC subpopulation in human and mouse UPS tumors. Our hypothesis is that the TIC fraction in UPS is responsible for maintaining UPS self-renewal and tumor growth, and that therapeutically targeting the TIC fraction can be developed into an effective UPS treatment. We will test this hypothesis by answering the following questions: 1) Will the eradication of TICs cause the degeneration of UPS? We found that deletion of Ng2 expressing cells in mouse UPS tumors, by driving Diphtheria Toxin in tumors established as allografts, will cause degeneration of tumors. Using flippase to activate oncogenic alleles to drive UPS development in mice, and cre-recombinase to drive Diphtheria Toxin in Ng2 expressing, we will be able to delete the TIC population in tumors in-situ, and determine if this causes degeneration of UPS tumors, prevents recurrence, or inhibits metastatic capacity. 2) Are individual clones within the Ng2 expressing population stable over time and resistant to conventional therapies? Ng2 expressing cells could be composed of cells that survive long term in tumors, giving rise to daughter cells that maintain the tumor over time; or they may represent different cells, each having TIC characteristics at different points in time. To determine which is the case, we will use the Confetti allele to label Ng2 expressing cells in mouse UPS tumors with different colored fluorescent proteins labeling individual clones. How these cell populations behave as the tumors grow, with serial transplantation, and after treatment using conventional therapies will determine which one of these possibilities is the case. 3) Can targeting NG2 be used to treat UPS? To determine how targeting Ng2 expression regulates tumor growth and self-renewal, NG2 will be knocked-down with shRNA in human UPS tumors established as xenografts in immunodeficient mice and NG2 will be deleted in primary mouse UPS tumors initiated by Cre recombinase that drives expression of oncogenes and recombines conditional Ng2 null alleles. Immunotherapy to NG2 will be examined in a similar manner in UPS tumors established as xenografts in immunodeficient mice. In addition to proving important biologic insight into sarcomas, these data will determine if short or long term therapeutic targeting of the TIC population will be more effective in UPS treatment, and inform a novel approach to develop a therapy based on targeting the UPS TIC.

描述（申请人提供）：未分化多形性肉瘤（UPS）是一种软组织肉瘤，预后最差。我们将建立在我们的发现，即UPS包含一个小的肿瘤起始细胞（TIC）的亚群，当移植到免疫缺陷小鼠时，这些细胞形成肿瘤的能力增强。我们的原理证明数据表明，在TIC群体中激活的治疗靶向信号通路抑制了在小鼠中作为异种移植物建立的UPS肿瘤的生长。在我们的初步数据中，我们确定了硫酸软骨素蛋白聚糖，NG 2，在人类和小鼠UPS肿瘤的TIC亚群中表达。我们的假设是，UPS中的TIC组分负责维持UPS自我更新和肿瘤生长，并且治疗靶向TIC组分可以发展成有效的UPS治疗。我们将通过回答以下问题来验证这一假设：1）TIC的根除是否会导致UPS的退化？我们发现，通过在作为同种异体移植物建立的肿瘤中驱动白喉毒素，小鼠UPS肿瘤中Ng 2表达细胞的缺失将导致肿瘤变性。使用翻转酶激活致癌等位基因以驱动小鼠中的UPS发展，并使用cre重组酶驱动Ng 2中的白喉毒素表达，我们将能够原位删除肿瘤中的TIC群体，并确定这是否导致UPS肿瘤的变性，防止复发或抑制转移能力。2)Ng 2表达群体中的单个克隆是否随时间推移而稳定并且对常规疗法具有抗性？Ng 2表达细胞可以由在肿瘤中长期存活的细胞组成，产生随时间推移维持肿瘤的子细胞;或者它们可以代表不同的细胞，每个细胞在不同的时间点具有TIC特征。为了确定是哪种情况，我们将使用Confetti等位基因来标记小鼠UPS肿瘤中的Ng 2表达细胞，其中不同颜色的荧光蛋白标记单个克隆。这些细胞群在肿瘤生长、连续移植和常规治疗后的表现将决定哪种可能性是这种情况。3)针对NG 2可以用于治疗UPS吗？为了确定靶向Ng 2表达如何调节肿瘤生长和自我更新，将在免疫缺陷小鼠中建立为异种移植物的人UPS肿瘤中用shRNA敲低NG 2，并且将在由Cre重组酶启动的原发性小鼠UPS肿瘤中缺失NG 2，Cre重组酶驱动癌基因的表达并重组条件性Ng 2无效等位基因。将以类似的方式在免疫缺陷小鼠中作为异种移植物建立的UPS肿瘤中检查对NG 2的免疫治疗。除了证明对肉瘤的重要生物学见解外，这些数据还将确定TIC人群的短期或长期治疗靶向在UPS治疗中是否更有效，并为开发基于靶向UPS TIC的治疗的新方法提供信息。