Fusion of the EWS-related gene TAF2N to TEC in extraskeletal myxoid chondrosarcoma.

Abstract

Extraskeletal myxoid chondrosarcomas (EMCs) are characterized by a recurrent t(9;22)(q22;q12) translocation, resulting in the fusion of the EWS gene in 22q12 and the TEC gene in 9q22. Here we report that a third member of the EWS, TLS/FUS gene family, TAF2N, can replace EWS as a fusion partner to TEC in EMC. Two tumors, one with a novel t(9;17)(q22;q11) variant translocation and one with an apparently normal karyotype, expressed TAF2N-TEC fusion transcripts. In both cases, the chimeric transcripts were shown to contain exon 6 of TAF2N fused to the entire coding region of TEC. This transcript is structurally and functionally very similar to the EWS-TEC fusions. The exchange of the EWS NH2-terminal part with the TAF2N NH2-terminal part in EMC further underscores the oncogenic potential of these protein domains as partners in fusion genes.