INS and neoplasm: Reduced glucose, insulin and IGF-1 levels or—more generally—DR activate an energy-sensing network consisting of AMPK, SIRT1, PPARα and PGC-1α with the potential to counteract tumor cell proliferation.35, 36 AMPK activation by anti-diabetic drugs such as metformin is currently considered a beneficial adjunct to standard cancer therapy.37, 38