HIF1A and neoplasm: In hypoxic tumor microenvironments, the stabilization of the oncogenic transcription factor hypoxia-inducible factor-1α (HIF1A, HIF-1α) regulates the expression of pyruvate dehydrogenase kinase-1 (PDK1), which subsequently limits ROS production by phosphorylating pyruvate dehydrogenase (PDH) and restricting mitochondrial metabolism [4].