MTOR and glioblastoma: Upregulations of PI-PLC and PI 3-kinase, PI 4-kinase, and/or other PI kinases would together activate the downstream Akt/mTOR signaling pathway (57), a commonly altered mechanism highly active in high percentage of glioblastoma (58) that promotes the survival, growth, proliferation, and mobility of tumor cells, resulting in a significant reduction of tumoral PIs.