CNR1 and glioblastoma: In contrast to relatively normal functions in neuronal and glial cells, the early effects of ∆THC-activated CB1/2 receptors in glioma/glioblastoma cells included a substantial upregulation of ceramide levels in the endoplasmic reticulum (ER) that resulted in the ER-stress response followed by autophagy and apoptosis [38, 39].