Further investigation revealed that PGC-1α mediates OXPHOS, thus promoting metastasis of normoxic colorectal CSCs.287 Hypoxia induces PGC-1α expression, which augments mitochondrial biogenesis, OXPHOS, antioxidant enzyme expression, migration, invasion, sphere formation, and proliferation and blocks apoptosis caused by the anti-cancer drug 5-fluorouracil in CRC cells, finally exacerbating tumorigenesis.288 Of note, when exposed to 5-fluorouracil, PGC-1α can also promote cancer cell survival via the modulation of mitochondrial function, ER stress, and the apoptotic signaling pathway.289. Here, PPARGC1A is linked to cancer.