CDKN1A and cancer: KCNQ1OT1 knockdown mediated various senescence markers (increased senescence-associated β-galactosidase staining, the p53-p21Cip1/WAF1 pathway, H3K9 trimethylation, and expression of the senescence-associated secretory phenotype) and reactive oxygen species generation via CK2α downregulation in human cancer HCT116 and MCF-7 cells.