MOLECULAR CYTOGENETICS--PEDIATRIC CNS TUMORS

细胞遗传学和分子技术促进了我们对 癌症的生物学基础，尤其是在儿童肿瘤中。 有关儿童中枢神经系统肿瘤的信息有 由于技术问题和联合获取标本的问题，这项工作受到了限制。为 这些原因，我们建议进行分子和细胞遗传学评估 儿童中枢神经系统肿瘤。在这个项目中，我们将从一个 儿科脑肿瘤的延伸系列。我们的研究将包括 肿瘤直接制剂分析及短期组织培养 肿瘤标本和外周血样。我们将研究等位基因的丢失 在中枢神经系统肿瘤的17P上缩小我们提出的包含一个基因座的区域 对PNETs的发展至关重要。我们将进一步定义和缩小 22q区域被认为包含一个肿瘤抑制基因 横纹肌样瘤或典型的脑部畸胎样肿瘤。易发生突变的“热点” 我们将对恶性肿瘤P53基因中的“斑点”进行测序，以评估 此基因突变在儿童中枢神经系统肿瘤中的频率。我们 将开发基于序列的诊断方法来检测I(17q)和 临床资料中有助于诊断这些亚群的单体22 肿瘤的症状。因此，从我们的研究中确定的DNA序列将被应用 用聚合酶链式反应检测临床标本中的相关异常 分析和间期荧光原位杂交。最后，我们 将这些细胞遗传学和分子分析的结果与 临床结果和免疫表型。这将涉及到比较 具有临床特点和临床特点的细胞遗传学和分子生物学表现 专门的免疫组织化学研究。当我们开始理解 通过识别基因，基因组改变的功能后果 以及它们发挥作用的机制，我们将 能够将这些信息转化为诊断和 心理治疗。

Cytogenetic and molecular techniques have advanced our knowledge of the biologic basis of cancer, particularly in the pediatric neoplasms. Information regarding pediatric tumors of the central nervous system has been limited due to technical problems and United access to specimens. For these reasons we propose a molecular and cytogenetic evaluation of pediatric CNS tumors. In this program, we will prepare karyotypes from an extended series of pediatric brain tumors. Our studies will include analysis of direct preparations from tumors, and short term tissue culture of tumor specimens and peripheral blood. We will examine loss of alleles on 17p in CNS tumors to narrow the region which we propose contains a locus critical to the development of PNETS. We will further define and narrow the region of 22q implicated as containing a tumor suppressor locus for rhabdoid or a typical teratoid tumors of the brain. Mutation-prone "hot spots" in the p53 locus of malignant tumors will be sequenced to assess the frequency of mutations in this locus in pediatric tumors of the CNS. We will develop sequence-based diagnostic assays for detection of i(17q) and monosomy 22 in clinical material to aid in the diagnosis of these subsets of tumors. Thus, DNA sequences identified from our studies will be applied to detection of the relevant abnormality in clinical samples by PCR analysis and interphase fluorescence in situ hybridization. Finally, we will correlate the findings of these cytogenetic and molecular assays with clinical outcome and immunophenotyping. This will involve comparisons of the cytogenetic and molecular findings with clinical characteristics and specialized immunohistochemical studies. As we begin to understand the functional consequences of genomic alterations, by identifying the genes involved and the mechanisms by which they exert their effect, we will be able to translate this information into improvements in diagnosis and therapy.