Gliomas are the most common brain tumors. Adult gliomas frequently present molecular alterations in the epidermal growth factor receptor (EGFR) and its associated signaling pathways. In recent work, researchers from the Centre de Biophysique Moléculaire (France) and collaborators demonstrated the role of the serotonin 5-HT7 receptor (5-HT7R) in a larval Drosophila model of glioma, showing that it may act as a tumor suppressor.