TP53 and colorectal cancer: To investigate the early consequences of tetraploidy and the evolution of newly formed tetraploid cells, we induced cytokinesis failure by dihydrocytochalasin B (DCB) treatment for 20 hr (Figure 1A) in both DLD-1 (pseudodiploid colorectal cancer cells) and p53-/- hTERT-immortalized RPE-1 cells (Izquierdo et al., 2014) (hereafter referred to as RPE-1 p53-/-; p53-null RPE-1 cells were used because the parental, p53-positive, cells display a G1 arrest after cytokinesis failure, as shown in Ganem et al., 2014).