Ewing sarcoma is consistently associated with chromosomal translocation and functional fusion of the EWSR1 gene to any of several structurally related transcription factor genes of the E26 transformation-specific family.
Fluorescence in situ hybridization (FISH) indicated a rearrangement of the EWS region on chromosome 22, which is highly specific for Ewing's sarcoma and PNET, which are referred to as the Ewing's sarcoma family of tumors (EFT).
EWSR1-FEV translocation is exceedingly rare in Ewing sarcoma, as FEV expression is restricted to prostate, brain and serotonin neuroendocrine cells (NE) and related tumours.
Ewing sarcoma (ES) family of tumors includes bone and soft tissue tumors that are often characterized by a specific translocation between chromosome 11 and 22, resulting in the EWS-FLI1 fusion gene.
All 30 clinical specimens had been confirmed to contain sufficient ES/PNET DNA by the demonstration of a rearrangement of the t(11;22)-associated EWS gene using an EWS cDNA probe on the same blots.
All ES tumor DNA samples previously were confirmed to have EWS rearrangements on the same Southern blots, using a cDNA probe spanning the EWS breakpoint region.
Cytogenetic and molecular cytogenetic studies of a variant of t(21;22), ins(22;21)(q12;q21q22), with a deletion of the 3' EWSR1 gene in a patient with Ewing sarcoma.
Results suggest that using a panel of immunohistochemical markers, including NKX2.2, CD99, FLI-1, EMA, GFAP and synaptophysin, combined with the supplementary EWSR1 FISH test, helps to define the diagnosis of meningeal ES/pPNET of CNS.
As a consequence, many alternative forms of EWSR1-ETS translocation exist which make the RNA-based molecular diagnostics of Ewing sarcoma family of tumours complicated.
More than 85% of Ewing's sarcoma and peripheral neuroectodermal tumor present a specific t(11;22)(q24;q12) balanced translocation, resulting in the production of a novel chimerical EWS/FLI-1 message.
Ewing's sarcoma (ES) and desmoplastic small round cell tumors (DSRCT) are small round blue cell tumors driven by an N-terminal containing EWS translocation.
EWS functions in RNA splicing and transcription by encoding an RNA binding protein, which results in the chromosomal translocation t(11;22)(q24;q12) found in Ewing sarcoma.
The defining cytogenetic abnormality of Ewing's sarcoma is the presence of a balanced t(11;22) translocation expressing the EWS/FLI-1 chimeric fusion protein.
The balanced translocation t(11;22)(q24;q12) is specific for the Ewing's sarcoma/peripheral primitive neuroectodermal tumors (ES/PNETs) and results in the EWS/FLI-1 fusion transcript, which can be detected by reverse transcription polymerase chain reaction (RT-PCR).
MiniSTR marker D22S1045 (locus 22q12.3) is localized near the breakpoint region of the EWS gene (22q12.2), which leads to the development of Ewing's Sarcoma.
This interaction has functional consequences in Ewing sarcoma (ES), childhood and adolescence bone malignancies driven by fusions between EWSR1 and FLI1.
In Ewing's sarcoma and related peripheral primitive neuroectodermal tumors, a (11;22)(q24;q12) translocation is associated with hybrid transcripts of the EWS gene with the FLIl gene.
The 11;22 chromosomal translocation specifically linked to Ewing sarcoma and primitive neuroectodermal tumor results in a chimeric molecule fusing the amino-terminal-encoding portion of the EWS gene to the carboxyl-terminal DNA-binding domain encoded by the FLI1 gene.