Several pre-clinical models reported the efficacy of metformin against glioblastoma cells, with different molecular mechanisms involving for example the chloride intracellular channel protein 1 (CLIC1) [32], the AMP-activated protein kinase (AMPK) [33], Akt and FOXO3 activation [34,35,36]. The gene discussed is CLIC1; the disease is glioblastoma.