Molecular Genetic Analysis of Synovial Sarcoma and its Application for Histologic Diagnosis

对92例恶性骨和软组织肿瘤的组织学检查和分子基因表达进行了研究。1)RT-PCR法检测嵌合转录产物。对RNA进行逆转录，并用特异的检测嵌合转录本的引物进行聚合酶链式反应(PCR)扩增。SYT-SSX14例，EWS-Flil 8例，PAX-FKHR 4例，EWS-ATF1。15例SYT-SSX嵌合转录本肿瘤中有10例初步诊断为滑膜肉瘤。其他5个肿瘤最初未分类或被认为是罕见部位的滑膜肉瘤；骨、心包、腹膜后。2)SSX基因正常表达的检测虽然正常SSX基因仅在正常睾丸和甲状腺组织中表达，但原位杂交发现SSX基因在滑膜肉瘤的上皮成分、纤维区和低分化细胞中均有表达。用SSX1探针进行Northern印迹分析，在所有滑膜肉瘤、6例尤文氏肉瘤、1例胚胎性横纹肌肉瘤中均检测到重排SSX1。3)应用于组织学诊断RT-PCR可以被认为是一种有用的分子生物学技术，可以为滑膜肉瘤与其他恶性骨和软组织肿瘤、尤文氏肉瘤、泡状横纹肌肉瘤、黏液样脂肪肉瘤、爪状细胞肉瘤的鉴别诊断提供客观依据。

We studied 92 malignant bone and soft tissue tumors on the histological examination and molecular gene expression.1) Detection of chimeric transcripts by RT-PCRTotal RNA was extracted from frozen specimens. RNA was reverse transcribed and the resulting cDNA was amplified by PCR using specific primers for detection of the chimeric transcripts. 15 tumors showed a major 585-bp DNA fragment of SYT-SSX.14 ; EWS-Flil, 8 ; PAX-FKHR, 4 ; EWS-ATF1.10 of 15 tumors had SYT-SSX chimeric transcript were initially diagnosed as synovial sarcoma. Other 5 tumors were initially unclassified or were considered synovial sarcoma in unusual locations ; bone, pericardium, retroperitoneum. The SSX1 gene was involved in 11, and the SSX2 gene ; 4 tumors.2) Detection of normal SSX gene expressionAlthough normal SSX gene was only expressed in normal testis and thyroid gland, expression of SSX gene using by in situ hybridization was found in the epithelial component, fibrous areas and poorly differentiated cells of synovial sarcoma cases. Northern blot analysis with SSX1 probe detected rearranged SSX1 in all of synovial sarcoma cases, 6 Ewing's sarcoma, one embryonal rhabdomyosarcoma.3) Application for histological diagnosisRT-PCR can be considered a useful molecular biological technique that can provide objective evidence for differential diagnosis between synovial sarcoma and other malignant bone and soft tissue tumors ; Ewing's sarcoma, alveolar rhabdomyosarcoma, myxoid liposarcoma, claer cell sarcoma.