HIF1A and cancer: Computational modeling of these circuits demonstrates that cancer cells can differentiate into any of the three safe phenotypic states (1): glycolytic, characterized by low AMPK activity and high HIF-1 (2); OXPHOS, characterized by low AMPK activity and high HIF-1; and (3) mixed glycolysis/OXPHOS, which arises when both HIF1 and AMPK levels are elevated (418).