MTOR and cancer: Neurons stimulate the proliferation of GBM cells through the secretion of neuroligin-3, which activates the PI3K-mTOR pathway.35 The PI3K-mTOR pathway is continuously stimulated in cancer cells, which promotes tumorigenesis and therapy resistance.36 In addition, neuronal signaling can activate calcium signaling in populations of GBM cells, driving microtube formation and invasion.37