GPLD1 and neoplasm: This review shows that phospholipases belonging to different families (PLA, PLC, and PLD) play a pivotal role in the regulation of cell signaling in brain tumors and are consequently implicated in the pathogenetic and clinical evolution of low- and high-grade gliomas as tumor suppressors or oncogene, thus proving to be attractive prognostic biomarkers or therapeutic targets, respectively, for these heterogeneous tumors with no real effective cure.