GLI1 and Cancer Stem Cells in Ewing Sarcoma

GLI1 和尤文肉瘤中的癌症干细胞

基本信息

批准号：
8009518
负责人：
William A May
金额：
$ 16.88万
依托单位：
CHILDREN'S HOSPITAL OF LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-01-01 至 2012-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8009518
关键词：
Adolescence Biological Assay Cancer Biology Cell Fraction Cell physiology Cells Chromosomal translocation Cytotoxic Chemotherapy DNA Binding Domain Development Diagnosis Erinaceidae Ewings sarcoma Exhibits FLI1 gene Family GLI gene Gene Expression Genes In Vitro Life Maintenance Malignant Childhood Neoplasm Malignant Neoplasms Measures Methods Pathway interactions Patients Pharmaceutical Preparations Phenotype Play Population Preclinical Testing Property Proteins Research Resistance Role Signal Pathway Signal Transduction Site Sorting - Cell Movement Stem cells System Test Result Testing Tumor Cell Line Undifferentiated Up-Regulation Work bone cancer stem cell cancer therapy chemotherapy in vivo inhibitor/antagonist insight neoplastic cell novel prototype public health relevance self-renewal small hairpin RNA small molecule soft tissue stem cell population therapy development transcription factor tumor tumorigenesis young adult

项目摘要

DESCRIPTION (provided by applicant): The horizons of cancer biology have been expanded by the concept of cancer stem cells (CSC). In concept, tumors may arise from and continue to harbor a stem cell population which is responsible for ongoing tumor self renewal. This distinct population may hold the key to understanding the development of treatment resistance. Because of these factors, the study of cancer stem cells promises novel insights into the origins and treatment of cancer. The Ewing Sarcoma Family of Tumors (ESFT) represents a particular challenge. Its cell of origin is unknown. While initially very responsive to chemotherapy, the emergence of treatment resistance occurs in over 40%, usually with fatal results. ESFT are united by a chromosomal translocation fusing the EWS gene an ETS transcription factor. The prototype fusion, EWS/FLI11 occurs in over 85% of cases. Abundant evidence supports a crucial role for EWS/FLI1 in ESFT through its function as an aberrant transcription factor. My lab has recently uncovered a novel effect of EWS/FLI1 in enhancing expression of GLI1 in ESFT. GLI1 is the effector of the Hedgehog/GLI (HH/GLI) signaling pathway. This pathway has prominent roles in development and in many malignancies. It has been shown to contribute to the maintenance of stem cell phenotype in other tumor systems. This proposal will investigate the hypothesis that GLI1 upregulation by EWS/FLI1 is critical to maintaining a stem cell compartment in ESFT and whether this CSC compartment is resistant to treatment Since ESFT have been shown to harbor CD133 positive CSC, we will select CD133 positive fractions from ESFT cell lines and perform in vivo tumorigenesis assays. Validated CD133 sorted ESFT cell populations will be assessed by gene expression array to assess the expression of GLI1 and its targets. We will also assess for other potential stem cell markers. The role of GLI signaling in ESFT CSC will be tested by measuring the quantitative effects of GLI1 inhibition on the CSC fraction. Methods of inhibition will include both GLI1 specific shRNA and small molecule inhibitors of GLI signaling. We will also test the results of GLI inhibition on CSC function by measuring the effect of GLI inhibition on CSC tumorigenesis assays. We will also test the hypothesis that stem cell populations are associated with treatment resistance and whether GLI1 contributes to this. This will be tested using validated CD133 positive CSC populations generated in Aim 1. Using systems in place for the Ewings Preclinical Testing Lab, we will measure any differences in sensitivity to a wide range of relevant drugs in already characterized ESFT cell lines. These changes will be documented by high throughput in vitro assessment of chemosensitivity (DIMSCAN). PUBLIC HEALTH RELEVANCE: Ewing's Sarcoma is a deadly cancer of childhood, adolescence and young adulthood which takes the life of over 40% of those diagnosed. This work will detail the role of Gli1 signaling in maintaining cancer stem cells in Ewing's Sarcoma. If Gli1 is important in maintaining cancer stem cells, these treatment- resistant cells can be specifically targeted with drugs, enhancing our ability to cure patients.

描述（由申请人提供）：癌症生物学的视野已通过癌症干细胞的概念（CSC）扩展。从概念上讲，肿瘤可能是由肿瘤群体引起的，并留下了造成肿瘤自我更新的干细胞群体。这种不同的人群可能是理解抗治疗抗性的关键。由于这些因素，癌症干细胞的研究有望对癌症起源和治疗的新见解。尤因肉瘤家族（ESFT）代表了一个特殊的挑战。它的原籍细胞是未知的。虽然最初对化学疗法的反应非常有反应，但治疗耐药性的出现在40％以上，通常是致命的。 ESFT由染色体易位融合，将EWS基因融合为ETS转录因子。原型融合，EWS/FLI11发生在超过85％的病例中。大量证据通过其作为异常转录因子的功能来支持EWS/FLI1在ESFT中的关键作用。我的实验室最近发现了EWS/FLI1在增强ESFT中GLI1表达的新作用。 Gli1是刺猬/GLI（HH/GLI）信号通路的效应子。该途径在发展和许多恶性肿瘤中具有重要的作用。已证明它有助于在其他肿瘤系统中维持干细胞表型。该提议将调查以下假设：EWS/FLI1上的Gli1上调对于维持ESFT中的干细胞室至关重要，并且由于ESFT已显示ESFT已显示出CD133阳性CSC，因此该CSC是否对治疗有抵抗力，我们将从中选择CD133阳性分数。 ESFT细胞系并执行体内肿瘤发生分析。经过验证的CD133分类ESFT细胞种群将通过基因表达阵列评估，以评估GLI1及其靶标的表达。我们还将评估其他潜在的干细胞标记。 GLI信号在ESFT CSC中的作用将通过测量GLI1抑制对CSC分数的定量作用来测试。抑制方法将包括GLI1特异性shRNA和GLI信号的小分子抑制剂。我们还将通过测量GLI抑制对CSC肿瘤发生分析的影响来测试GLI抑制对CSC功能的结果。我们还将检验以下假设：干细胞群体与治疗耐药性以及GLI1是否有助于这一假设。将使用AIM 1中生成的经过验证的CD133正CSC种群对此进行测试。使用eWings临床前测试实验室的系统，我们将测量对已经具有特征的ESFT细胞系中对广泛相关药物的敏感性的任何差异。这些变化将通过高通量的体外评估（DIMSCAN）记录。公共卫生相关性：尤因的肉瘤是一种致命的童年，青春期和年轻成年的癌症，占据了40％的被诊断患者的生命。这项工作将详细介绍GLI1信号在尤因肉瘤中维持癌症干细胞中的作用。如果GLI1在维持癌症干细胞中很重要，则可以将这些耐药细胞专门针对药物，从而增强我们治愈患者的能力。