Repurposed drugs meeting these requirements include some inhibitors of the mammalian target of rapamycin (mTOR; e.g., rapamycin and temsirolimus) as anti-cancer drugs, the activators of the negative mTOR regulator AMP-activated protein kinase (AMPK; e.g., the anti-diabetic metformin), the anti-epileptic carbamazepine used in the treatment of trigeminal neuralgia, and some anti-cancer drugs. Here, MTOR is linked to cancer.