New Mechanism Described in This Research (IMAGE) CNRS Caption Mesenchymal stem cells (on the right) are associated with metastatic dissemination, resistance to conventional chemotherapy and to relapses. During the transition to this state, the protein CD44 takes over from transferrin and its TfR1 receptor and ensures the majority of the iron endocytosis. This leads to a significant increase in cellular ion concentration. In the nucleus, iron operates as a chemical catalyst for oxidative demethylation and "releases" genes whose expression is reprimed by methylated histone proteins, in particular those involved in metastatic dissemination. Accordingly, CD44 regulates the epigenetic plasticity and expression of these genes by iron mediation. Credit © Raphaël Rodriguez/Nature Usage Restrictions May only be used to report on this research, with full credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.