TP53 and cancer: FOXM1, a transcriptional activator of cell cycle genes overexpressed in various cancers [67], and a DREAM target [66], was highly expressed in untreated HF2303 and HF2927 cells and downregulated exclusively in HF2927 CSCs and SDCs 5 days after RT, indicating the prolonged effect of cell cycle arrest through downregulation of cell cycle genes, downstream of p53 activation.