ESRRA and cancer: PGC-1α expression in cancer cells is induced by ROS (H2O2) and in turn works with the estrogen-related receptor α (ERRα) to induce expression of many genes involved in oxidative metabolism (including glycolysis, TCA cycle, OxPhos and lipid oxidation; Figure 1) and many of these overlap with those regulated by the hypoxic factors, HIFs, and their induced genes, such as VEGF.