By single gene knockout using CRISPR/Cas9 technique in human epidermoid carcinoma MDR cell line KB-C2, we recently revealed that CDK6-PI3K signaling axis is an efficient target for attenuating ABCB1/P-gp mediated MDR in cancer cells (Zhang et al., 2022). This evidence concerns the gene ABCB1 and squamous cell carcinoma.