p21WAF1/CIP1 deficiency induces mitochondrial dysfunction in HCT116 colon cancer cells

► p21−/− HCT116 cells exhibited an increase in mitochondrial mass. ► The expression levels of PGC-1α and AMPK were upregulated in p21−/− HCT116 cells. ► The proliferation of p21−/− HCT116 cells in galactose medium was significantly impaired. ► p21 may play a role in maintaining proper mitochondrial mass and respiratory function.