Furthermore, the switch from OXPHOS to glycolysis has also been observed in tumor-repopulating cells (TRCs), a stem cell-like subpopulation with highly invasive phenotypes that are responsible for tumor regeneration, by regulating phosphoenolpyruvate carboxykinase 1 (PCK1) and PCK2 [43, 44]. Here, PCK1 is linked to neoplasm.