Demonstration of PDGFRA amplification as the most common CNA among pediatric HGG, and the association of histone H3.3 mutation in malignant pediatric brain-stem glioma with PDGFRA amplification, identified PDGFRα and its signaling pathways as likely integral to the malignant behavior of some tumors. This evidence concerns the gene PDGFRA and brain stem glioma.