However, there is significant morphologic heterogeneity and overlap with a variety of other neoplasms, which can cause diagnostic challenge, particularly as the immunoprofile is varied, SS18-SSX is not detected in 100% of SSs, and they may occur at unusual sites.
In summary, SS18-SSX-induced Wnt/β-catenin signaling appears to be of crucial biological importance in synovial sarcoma tumorigenesis and progression, representing a potential molecular target for the development of novel therapeutic strategies.
Our objective was to evaluate the expression of apoptotic pathway members in synovial sarcomas and interrogate the impact of modulating SS18-SSX expression on this pathway.
To investigate the underlying mechanism, we studied human synovial sarcoma (SS), in which transformation results from the translocation of exactly 78 amino acids of SSX to the SS18 subunit of BAF complexes.
Although precise function of SYT-SSX remains to be investigated, accumulating evidences suggest its role in gene regulation via epigenetic mechanisms, and the product of SYT-SSX target genes may serve as biomarkers of SS.
This study may be valuable for understanding the pathogenic role and molecular mechanism of the fusion gene SYT-SSX in synovial sarcoma through the proposed genome-wide approach.
Collectively, these data suggest that a human multipotent mesenchymal stem cell can serve as a cell of origin for SS and SS is a stem cell malignancy resulting from dysregulation of self-renewal and differentiation capacities driven by SS18-SSX fusion protein.
Synovial sarcoma (SS) is an aggressive soft-tissue malignancy characterized by a unique t(X;18) translocation resulting in expression of SS18-SSX fusion protein.
Prognostic implication of SYT-SSX fusion type and clinicopathological parameters for tumor-related death, recurrence, and metastasis in synovial sarcoma.
A characteristic SYT-SSX fusion gene resulting from the chromosomal translocation t(X;18)(p11;q11) is detectable in almost all synovial sarcomas, a malignant soft tissue tumor widely believed to originate from as yet unidentified pluripotent stem cells.
Prospectively, FNAs positive for the SYT-SSX fusion transcript by RT-PCR (n = 6) and, retrospectively, cases proven on histopathology and immunohistochemistry (ICC; positivity for vimentin and epithelial membrane antigen [EMA]/cytokeratin) as SS (n = 10) were included in the study.
In conclusion, the SYT-SSX fusion type is not a significant prognostic factor unlike tumor size, followed by histological grade for patients with localized synovial sarcoma in Japan.
Substantial evidence indicates that the characteristic SS18-SSX fusion gene may play an important role in synovial sarcoma development and progression.
The presence of a specific diagnostic t(X;18) translocation leading to expression of the unique SYT-SSX fusion protein in effectively all cases of synovial sarcoma suggests a role in the etiology.
Detection of SS18-SSX fusion transcripts in formalin-fixed paraffin-embedded neoplasms: analysis of conventional RT-PCR, qRT-PCR and dual color FISH as diagnostic tools for synovial sarcoma.