Clinical impact of brachyury expression in Ewing sarcoma patients

The T-box transcription factor brachyury has been demonstrated as a prognostic factor in a variety of cancer types and considered a novel oncotarget in solid tumors. Brachyury acts as a regulator of the epithelial-mesenchymal transition (EMT) process, leading to more aggressive behavior and poorer prognosis. However, recent literature evidence suggests a tumor suppressor role in other neoplasms. In the present study, we aimed to study brachyury expression and its prognostic impact in Ewing sarcoma, an aggressive neoplasm of young individuals.

We analyzed the expression of brachyury by immunohistochemistry in a series of 96 Ewing sarcomas in a tissue microarray and investigated the association of the protein expression with the clinical parameters and overall survival.

More than half of the cases (51%, n ​= ​49) depicted positive nuclear brachyury expression, while a lack of expression was observed in 49% (n ​= ​47) of cases. Nuclear brachyury staining was significantly associated with non-white ethnicity (p ​= ​0.04) and axial localization (p ​= ​0.025). Importantly, lack of brachyury expression was significantly associated with lower overall survival in multivariate analyses (hazard ratio - HR: 2.227, p ​= ​0.008).

Our findings indicate, that brachyury is an independent prognostic biomarker in Ewing sarcoma, which might suggest a tumor suppressor role and which yet to be fully elucidated.