Researchers at the SJD Barcelona Children's Hospital and the Hospital del Mar discover the cellular origin of Ewing sarcoma

A study led by the SJD Research Institute (IRSJD) and the Hospital del Mar Research Institute has solved one of Ewing sarcoma’s greatest mysteries: its cellular origins.

Researchers found that this aggressive pediatric tumor begins in mesenchymal embryonic stem cells, which are found in the embryonic tissue that later becomes muscle tissue, connective tissue, blood vessels, lymph vessels, etc. These cells acquire an oncogene very early in fetal development. This discovery will aid understanding of how the disease begins and will provide new opportunities to study what triggers tumor progression.

The team was able to reproduce this mechanism in a controlled environment by introducing the oncogene in question to lab-grown human mesenchymal cells. Although these cells are not cancerous in-vitro, when injected into mice, they can develop into tumors that faithfully replicate the characteristics of Ewing sarcoma in humans. This milestone provides a model that allows researchers to analyse the processes though which an apparently normal cell can transform into a tumor cell, as well as a way to detect possible therapeutic vulnerabilities.

Dr Jaume Mora, Scientific Director of the Pediatric Cancer Center Barcelona at the SJD Barcelona Children’s Hospital and Head of the Sarcomas and Neuroblastoma research group at the IRSJD, highlights the significance of this discovery: ‘Identifying this cellular origin allows us to better understand how and why cancerous processes begin, forging new paths to developing more targeted, less harmful therapies for pediatric patients.’ This reinforces the objective of turning new knowledge into more effective treatments with fewer side effects for children and adolescents.

This research is funded by La Marató de 3Cat.