Ewing sarcoma is a tumor of the bones and soft tissues that occurs in children and young people. Like all childhood cancers, it is rare – 9 to 10 cases per million inhabitants per year – but it is very aggressive. 25% of patients do not respond well to regular therapy and they often experience relapses.
A new study led by Ana Losada, head of the Chromosomal Dynamics Group at Spain's National Cancer Research Centre (CNIO), identifies several mechanisms that increase the aggressiveness of Ewing sarcoma, promoting metastasis and leading to a poorer prognosis. This finding opens up new avenues for seeking treatments, since it "provides a list of potential [prognosis] biomarkers and therapeutic targets," the authors write in EMBO Reports . Ana Cuadrado is co-corresponding author of the study and Daniel Giménez-Llorente is the first author.
Ewing sarcoma is caused by the abnormal fusion of two genes, which results in an oncogene. The protein produced by this oncogene causes the expression of genes that promote tumour development. It was already known that the absence of a protein known as STAG2 amplifies the harmful effect of this oncogene, but the new study now shows that there are also alterations in the expression of many other genes.
Ana Cuadrado, corresponding author of the study, explains that the absence of the STAG2 protein "also modifies the expression of other genes that do not depend on the oncogene, and these changes also increase tumour aggressiveness". A key pro.
