DIFFERENTIATION AND NGF RECEPTOR FOR NEUROBLASTOMA.

13号染色体的生殖系或获得性改变已经被 与视网膜母细胞瘤、骨肉瘤和 肺泡横纹肌肉瘤 组成性染色体缺失 13ql4的基因被认为是视网膜母细胞瘤的病因，而 骨肉瘤中的13号染色体DNA缺失最近被 检测到 一个cDNA，rb-1，定位于13q14， 作为肿瘤抑制基因，已经被分离出来， 确定其在其他肿瘤中的作用正在开始。 细胞遗传 骨肉瘤的研究表明复杂的核型和缺乏 正常的13号染色体 腺泡状横纹肌肉瘤 易位，t（2; 13）。断点在13q14，这表明 Rb-1或紧密连锁基因座的参与。 我们建议 确定骨肉瘤和横纹肌肉瘤是否 在13q14基因组的类似区域的改变。 我们将 探索它们如何相互关联以及与RB-L基因座的关系， 诊断目的。 我们的具体目标是： I. 检查13号染色体参与肺泡上皮细胞 横纹肌肉瘤，使用细胞遗传学和分子生物学的组合， 技术使用rb. l探针的Southern和北方印迹 将被执行。 匿名多态13q探针和Southern 将使用印迹分析来检查杂合性与纯合性 在匹配的肿瘤和正常组织中。 二. 检查骨肉瘤中13号染色体的完整性， 细胞遗传学和分子技术的结合。 南部 rb-l和rb-l的印迹和染色体原位杂交 13q的匿名探针将用于确定是否 转化为纯合性是由于13号染色体丢失或 重排 三.表征染色体13处或附近的DNA序列， 腺泡状横纹肌肉瘤的t（2; 13）断点。 制作该区域有限的长距离限制性图谱 使用脉冲场凝胶电泳，并比较肿瘤和 将需要来自相同患者的正常生殖系DNA。 我们将分子生物学研究 通过经典的细胞遗传学研究，在临床环境中， 为这些肿瘤的遗传病因学提供了新的信息， 提供了一种分子诊断方法。

Germ line or acquired alterations of chromosome 13 have been associated with tumorigenesis for retinoblastoma, osteosarcoma, and alveolar rhabdomyoscaroma. Constitutional chromosomal deletions of 13ql4 are considered etiologic for retinoblastoma, whereas chromosome 13 DNA deletions in osteosarcomas have recently been detected. A cDNA, rb-1, which maps to 13ql4 and has been suggested as a tumor-suppressor gene, has been isolated, and studies to determine its role in other tumors are beginning. Cytogenetic studies of osteosarcomas indicate complex karyotypes and absence of normal chromosome 13s. Alveolar rhabdomyosarcomas have a translocation, t(2;13). with breakpoint at 13q14, suggesting involvement of rb-l or a closely linked locus. We Propose to determine whether osteosarcomas and rhabdomyosarcomas have alterations of a similar region of the genome in 13q14. We will explore how they relate to one another and to the rb-l locus for diagnostic purposes. Our specific aims are to: I. Examine the involvement of chromosome 13 in alveolar rhabdomyosarcoma using a combination of cytogenetic and molecular techniques Southern and Northern blotting using the rb.l probe will be performed. Anonymous polymorphic 13q Probes and Southern blot analysis will be used to examine hetero-versus homo-zygosity in matched tumor and normal tissues. II. Examine the integrity of chromosome 13 in osteosarcomas using a combination of cytogenetic and molecular techniques. Southern blotting and chromosomal in situ hybridization of the rb-l and anonymous Probes for 13q will be used to determine whether conversion to homozygosity is due to chromosome 13 loss or rearrangement. III. Characterize the chromosome 13 DNA sequences at or near the breakpoint for the t(2;13) of alveolar rhabdomyosarcoma. Production of a limited long-range restriction map of the region using pulsed-field gel electrophoresis, and comparison of tumor and normal germ-line DNA from the same patients will be required. Our unique ability to correlate molecular biologic investigation with classical cytogenetic studies, in a clinical setting will provide new information on the genetic etiology of these tumors and provide a molecular approach to their diagnosis.