DETECTION OF P53 MUTATIONS IN EWING'S SARCOMA AND RHABDOMYOSARCOMA

p53突变已在许多肿瘤中检测到，并被解释为晚期肿瘤。 肿瘤发生中的事件，可能涉及肿瘤进展，而不是 肿瘤发展 最近的研究表明， 在某些Li-Fraumeni家系中存在生殖系p53突变， p53突变与人类癌症遗传易感性 横纹肌肉瘤是一种常见的软组织肉瘤，多发生在有横纹肌肉瘤家族中， Fraumeni综合征，被发现有p53突变。 然而，频率 这种突变在儿科肿瘤中的普遍性仍是未知的。 我们将 研究尤文肉瘤细胞中p53突变的存在 与横纹肌肉瘤细胞系的现有数据进行比较。 此外，将在石蜡包埋组织中研究p53突变 从横纹肌肉瘤肿瘤，以探讨石蜡的有效性 用于此类研究的包埋组织。 突变的检测将是 对跨越p53外显子4、5、6、7和8的PCR片段进行 基因 将比较两种方法：标准单链 构象多态性（SSCP）方法和非放射性方法， 基于双链分子的构象差异 （异源双链分析）和使用非变性电泳， 突变检测增强（MDE）凝胶。

p53 mutations have been detected in many tumors and interpreted as a late event in tumorigenesis, probably involved in tumor progression rather than tumor development. Recent studies have demonstrated the presence of germline p53 mutations in some Li-Fraumeni pedigrees and hence a role of p53 mutations in hereditary susceptibility to human cancer. Rhabdomyosarcoma, a common soft tissue sarcoma in the families with the Li- Fraumeni syndrome, was found to have p53 mutations. However, the frequency of such mutations in pediatric tumors in general remains unknown. We will study the presence of p53 mutations in established Ewing's sarcoma cell lines in comparison with existing data from rhabdomyosarcoma cell lines. In addition, p53 mutations will be studied in paraffin embedded tissues from rhabdomyosarcoma tumors to investigate the validity of paraffin embedded tissues for such studies. The detection of mutations will be performed on PCR fragments spanning exons 4, 5, 6, 7, and 8 of the p53 gene. Two methods will be compared: the standard single stranded conformational polymorphism (SSCP) method, and a non-radioactive method, based on conformational differences in double stranded molecules (heteroduplex analysis) and using non-denaturing electrophoresis in mutation detection enhancement (MDE) gels.