MUSCLE DETERMINATION GENES IN THE DIAGNOSIS OF CHILDHOOD TUMORS

虽然横纹肌肉瘤与其他圆细胞肿瘤的区别 在大多数情况下， 关于什么意味着原始横纹肌肉瘤和 皮肤外尤文氏肉瘤是有效的 此外，这一论点 这不仅仅是一个哲学问题，因为病人 横纹肌肉瘤的治疗方案与 尤因氏肉瘤。 最近，我们用化学方法研究了 假常染色体MIC 2基因的产物在一系列 儿童肿瘤，并发现该产品的优先表达， 尤文氏肉瘤和横纹肌肉瘤缺乏尤文氏肉瘤。 然而几 表达1或2种肌肉标志物（即骨骼肌动蛋白）的原始肿瘤 和/或结蛋白）和超微结构外观有利于原始的 横纹肌肉瘤，被发现阳性的MIC 2产品，而其他 有相似特征的都是阴性。 由于几个肌肉 最近已经克隆了决定基因，并且cDNA探针已经成为 我们决定研究这些基因的表达 在相同的情况下，已经研究了MIC 2基因产品，并发现 如果这些标记比MIC 2基因更可靠， 产品或现有的针对肌肉蛋白的抗体。 为此 研究中，将从石蜡包埋的50微米切片中提取DNA 组织，并将通过Southern印迹分析是否存在 MyoD 1、肌细胞生成素、Myf 5、Myf 6、骨骼肌球蛋白重链和肌肉 肌酸激酶 这些标记相对于传统标记的价值 将被严格评估，特别是在那些原始的情况下， 由于免疫组化数据相互矛盾而难以区分。

Although distinction of rhabdomyosarcoma from the other round cell tumors of the soft tissues in children is not difficult in most cases, the argument as to what connotes a primitive rhabdomyosarcoma and an extraskeletal Ewing's sarcoma is a valid one. Furthermore, this argument comprises more than a philosophical question, since patients with rhabdomyosarcoma are treated in a different protocol than those with Ewing's sarcoma. We have recently studied immunohistochemically the presence of the product of the pseudoautosomal MIC2 gene in a series of childhood tumors and found preferential expression of this product by Ewing's sarcoma and lack thereof in rhabdomyosarcoma. However, a few primitive tumors expressing 1 or 2 muscle markers (i.e. skeletal actin and/or desmin) and ultrastructural appearance favoring a primitive rhabdomyosarcoma, were found positive for the MIC2 product, while others with similar characteristics were negative. Since several muscle determination genes have recently been cloned and cDNA probes have become commercially available, we decided to study the expression of these genes in the same cases that have been studied by the MIC2 gene product and find out if these markers are more reliable of myogenesis than the MIC2 gene product or the existing antibodies against muscle proteins. For this study, DNA will be extracted from 50 micron sections of paraffin-embedded tissues and will be analyzed by Southern blotting for the presence of MyoD1, Myogenin, Myf5, Myf6, skeletal myosin heavy chain and muscle creatine kinase. The value of these markers over the more traditional ones will be critically evaluated, especially in those primitive cases that are difficult to distinguish because of conflicting immunohistochemical data.