CDKN1A and cancer: Consistent with the reduction of the p53 responsive bioluminescence, a decrease or delay in the p53 transcriptional targets, p21, TRAIL Death Receptor DR5 and MDM2 at the protein level was detected in cancer cells transfected with the pcDNA-SARS2-spike, as compared to the pcDNA3.1 transfection at different post-treatment time points (Figure 3C, 3D).