The Role of PDGFR in Medulloblastoma Progression

PDGFR 在髓母细胞瘤进展中的作用

基本信息

批准号：
7585752
负责人：
TOBEY J. MACDONALD
金额：
$ 25.75万
依托单位：
CHILDREN'S RESEARCH INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-05-01 至 2009-09-07
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7585752
关键词：
Adhesions Affect Apoptosis Biological Process Blocking Antibodies Brain Cell Proliferation Regulation Cell Surface Receptors Cells Child Clinical Commit Computer Simulation Cranial Irradiation Data Data Set Development Disease Dose Environment Gene Expression Genes Goals Growth Growth Factor Human In Vitro Infant Malignant - descriptor Malignant neoplasm of brain Mitogen-Activated Protein Kinases Molecular Morbidity - disease rate Multipotent Stem Cells Neoplasm Metastasis Neural Crest Neuraxis Neurologic Neurons Outcome PDGF receptor tyrosine kinase PDGFRA gene PDGFRB gene Pathogenesis Pathway interactions Patients Pattern Phenotype Phosphorylation Platelet-Derived Growth Factor Receptor Platelet-Derived Growth Factor alpha Receptor Play Population Proteins RNA RNA Interference Receptor Mediated Signal Transduction Receptor Signaling Regulation Reporting Research Research Personnel Role Signal Transduction Signal Transduction Pathway Small Interfering RNA Stimulus Structure Survival Rate Survivors Testing Therapeutic Therapeutic Intervention Transfection Tumor Biology autocrine base cell growth cell motility design effective therapy experience in vivo inhibitor/antagonist mRNA Expression medulloblastoma medulloblastoma cell line migration neoplastic cell novel novel therapeutics outcome forecast overexpression paracrine precursor cell prevent protein activation protein expression receptor receptor expression response tumor

项目摘要

Medulloblastoma is the most common malignant brain tumor in children. To approach the problem of effective therapy, the progression of human medulloblastoma must first be understood. We hypothesize that )latelet-derived growth factor (PDGFR)-mediated signal transduction enhances tumor cell responses that promote the growth and metastatic spread of medulloblastoma, and have shown that (i) PDGFR is significantly overexpressed by metastatic medulloblastomas, (ii)inhibitors of medulloblastoma cell PDGFR activity decrease phosphorylation of the downstream signaling target, MAPK, alter gene expression, and decrease cell migration and survival and (iii) in silico analysis of 135 known pro-metastatic genes within ndependent datasets of microarraygene expression of medulloblastomas, only three genes, including DDGFR, demonstrated detectable mRNA expression in at least one third of all tumors analyzed and significant overexpression by metastatic tumors in each dataset. These data, combined with the preliminary data showing that both alpha (PDGFRA) and beta (PDGFRB) subtypes of the receptor are 1) expressed on the RNA and protein level by medulloblastoma tumors and cells, 2) sparsely expressed by normal brain, 3) activated in an autocrine and paracrine fashion in medulloblastoma cells, and 4) capable of inducing apoptosis of medulloblastoma cells in a dose-dependent manner following treatment with a selective inhibitor of PDGFR tyrosine kinase activity, suggest a mechanism by which PDGFR may be vital for medulloblastoma growth and progression. Thus, PDGFR is a potential novel target for therapeutic intervention. To test this hypothesis we will employ human medulloblastoma cell lines. We will (i) conduct comprehensive in vitro studies to determine the PDGFR signaling cascade and its effects on survival, proliferation, adhesion, migration and invasion, (ii) determine the key gene expression changes induced by PDGFR signaling in these cells, (iii) develop medulloblastoma cells with deficient PDGFR expression by inducible siRNA transfection specific for each PDGFR and determine the effect of inhibited expression and activity on survival, proliferation and migration in vitro and growth and metastasis in vivo, and (iv) determine the expression pattern of phbsphorylated PDGFR protein and its correlation with metastasis and outcome in human medulloblastomas as a way to assessthe potential clinical utility of PDGFR inhibitors for this disease

髓母细胞瘤是儿童最常见的恶性脑肿瘤。为了解决这个问题要进行有效的治疗，首先必须了解人类髓母细胞瘤的进展。我们假设）晚期衍生生长因子（PDGFR）介导的信号转导增强肿瘤细胞反应，促进髓母细胞瘤的生长和转移扩散，并表明 (i) PDGFR 转移性髓母细胞瘤显着过度表达，(ii) 髓母细胞瘤细胞 PDGFR 抑制剂活性降低下游信号传导靶标 MAPK 的磷酸化，改变基因表达，以及减少细胞迁移和存活，以及 (iii) 对 135 个已知的促转移基因进行计算机分析髓母细胞瘤微阵列基因表达的独立数据集，只有三个基因，包括 DDGFR，在所有分析的肿瘤中至少三分之一显示出可检测到的 mRNA 表达每个数据集中转移性肿瘤显着过度表达。这些数据，结合初步数据显示受体的 α (PDGFRA) 和 β (PDGFRB) 亚型 1) 均表达于髓母细胞瘤肿瘤和细胞的 RNA 和蛋白质水平，2) 正常大脑稀疏表达，3) 在髓母细胞瘤细胞中以自分泌和旁分泌方式激活，并且 4) 能够诱导用选择性抑制剂治疗后，髓母细胞瘤细胞以剂量依赖性方式凋亡 PDGFR 酪氨酸激酶活性的变化表明 PDGFR 对髓母细胞瘤可能至关重要成长和进步。因此，PDGFR 是治疗干预的潜在新靶点。为了测试这个假设我们将使用人类髓母细胞瘤细胞系。我们将 (i) 进行全面的体外研究确定 PDGFR 信号级联及其对生存、增殖、粘附、迁移和入侵，(ii) 确定 PDGFR 信号传导诱导的关键基因表达变化这些细胞，(iii) 通过诱导型 siRNA 发育出 PDGFR 表达缺陷的髓母细胞瘤细胞对每种 PDGFR 进行特异性转染，并确定抑制表达和活性对体外存活、增殖和迁移以及体内生长和转移，以及 (iv) 确定磷酸化 PDGFR 蛋白的表达模式及其与转移和结局的相关性人类髓母细胞瘤作为评估 PDGFR 抑制剂治疗该疾病的潜在临床效用的一种方法