They include activation of AMPK in tumor cells or suppression of: mammalian target of rapamycin (mTOR), mitogen-activated protein kinase (MAPK), protein kinase B (Akt), insulin//IGF-1 axis, NFκB pathways, and inhibition of complex 1 of the mitochondrial electron transport chain [36,97,98,245,246,247,248,249,250,251,252,253,254,255,256] Furthermore, it was reported that metformin suppresses epithelial to mesenchymal transition and directly kill stem cells [257]. Here, MTOR is linked to neoplasm.