Sequence analysis of translocation t (X; 18) genomic breakpoints characterized in synovial sarcoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To analyze the DNA sequence characteristics of translocation t (X; 18) genomic breakpoints and to study the mechanism underlying chromosomal translocation t (X; 18) in synovial sarcoma.</p><p><b>METHODS</b>Two cases of synovial sarcoma were studied utilizing long-distance polymerase chain reaction (PCR) and sequence analysis to amplify the genomic DNA of translocation t (X; 18) breakpoints.</p><p><b>RESULTS</b>Translocation t (X; 18) was detected in both cases, which generated SYT-SSX1 and SYT-SSX2 fusion gene respectively. Sequence analysis revealed that intron 10 of SYT was fused to the intron 4 of SSX1 or SSX2. Sequences highly homologous to consensus recognition motifs of translin were found adjacent to breakpoints in all three genes. Breakpoints in the three genes were close to or even at several palindromic oligomer sequences. The breaks in intron 4 of SSX1 and SSX2 were near an Alu sequence. No Alu or other repetitive sequences were found 500 bp upstream or downstream from the break in intron 10 of SYT. One topoisomerase II consensus site was found between the two breakpoints but with considerable distance from intron 10 of SYT.</p><p><b>CONCLUSIONS</b>All three genes involved in synovial sarcomas contain characteristic sequence motifs in the breakpoint regions which may play an important role in the genesis of chromosomal translocation in synovial sarcoma.</p>

Detection of SYT-SSX fusion transcripts in paraffin-embedded tissues of synovial sarcoma by reverse transcription-polymerase chain reaction / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To assess the feasibility of detecting SYT-SSX fusion transcripts in paraffin-embedded tissues of synovial sarcoma by reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>METHODS</b>RT-PCR was used to amplify the SYT-SSX fusion transcripts using archival formalin-fixed paraffin-embedded tumor specimens from a series of 37 synovial sarcoma cases. To investigate the specificity of the SYT-SSX fusion transcripts, a variety of non-synovial sarcoma tumors were included in the study as negative controls. The detected messages derived from fusion genes were confirmed by subsequent sequence analysis.</p><p><b>RESULTS</b>SYT-SSX fusion transcripts were detected in 33 of 37 (89.2%) synovial sarcomas. None of the 34 cases of non-synovial sarcoma tumors showed amplified products of SYT-SSX fusion transcripts, although PBGD mRNA was detected in all specimens. Among 33 SYT-SSX-positive synovial sarcomas, 22 tumors had an SYT-SSX 1 fusion transcript, whereas 6 tumors had an SYT-SSX2 fusion transcript. Fusion types can not be distinguished in the remaining 5 cases. There was a significant relationship between SYT-SSX fusion type and histologic subtype. All 10 biphasic synovial sarcomas had the SYT-SSX1 fusion, whereas all tumors with SYT-SSX2 were of monophasic morphology (P < 0.05).</p><p><b>CONCLUSIONS</b>RT-PCR can be applied to archival formalin-fixed paraffin-embedded tumor tissues as a sensitive and reliable technique for the diagnosis and differential diagnosis of synovial sarcoma. There is an association between SYT-SSX fusion type and histological subtype. SYT-SSX2 fusion transcripts can only be found in monophasic synovial sarcoma.</p>

Relationship between chromosomal translocation and synovial sarcoma / 中国癌症杂志

Synovial sarcoma is a high grade malignant soft tissue tumor. Its diagnosis and differential diagnosis are difficult. In most cases the reciprocal chromosomal translocation between chromosome X and chromosome 18 could be found and characterized synovial sarcoma. This article reviewed the relationship between chromosomal translocation and the diagnosis, histological type and prognosis of synovial sarcoma.