Targeting tumor mitochondrial metabolism overcomes resistance to antiangiogenics

Epithelial malignancies are effectively treated by antiangiogenics; however, acquired resistance is a major problem in cancer therapeutics. Epithelial tumors commonly have mutations in the MAPK/Pi3K-AKT pathways, which leads to high-rate aerobic glycolysis. Here, we show how novel multikinase inhibitor antiangiogenics (TKIs) induce hypoxia correction in spontaneous breast and lung tumor models. When this happens, the tumors down-regulate glycolysis and switch to long-term reliance on mitochondrial respiration. A transcriptomic, metabolomic and phosphoproteomic study revealed that this metabolic switch is mediated by down-regulation of HIF1α and AKT and up-regulation of AMPK, allowing uptake and degradation of fatty acids and ketone bodies. The switch renders mitochondrial respiration necessary for tumor survival. Agents like phenformin or ME344 induce synergistic tumor control when combined with TKIs, especially in a sequential schedule, leading to metabolic synthetic lethality. Our study uncovers new mechanistic insights in the process of tumor resistance to TKIs, and may have clinical applicability