In keeping with the notion that TRAF6 positively regulated PD-L1 stability, depletion of endogenous TRAF6 using sgRNAs markedly decreased the PD-L1 protein level, but did not significantly affect the PD-L1 mRNA level in multiple cancer cell lines (Fig. 3d–g and Supplementary Fig. 3e, f). This evidence concerns the gene CD274 and cancer.