CDK5 and cancer: We found that CDK5 was inhibited only in T24 and UMUC3 cells, and the inhibitory effect of CDK5 was more obvious in the presence of SDA, indicating that NSGEP only driven the expression of CRISPR-CasΦ only in cancer cells and the SDA could improve the efficiency of CRISPR-CasΦ (Fig. 3D).