p53 deacetylation by SIRT1 decreases during protein kinase CKII downregulation-mediated cellular senescence

► CKII inhibition induced acetylation of p53 at K382 in HCT116 and HEK293 cells. ► This acetylation was suppressed by SIRT1 activation. ► CKII interacted with SIRT1 and CKII inhibition reduced SIRT1 activity. ► SIRT1 overexpression antagonized CKII inhibition-mediated cellular senescence. ► Thus, CKII inhibition stabilizes p53 by downregulating SIRT1 during senescence.