USP8 and cancer: Consistent with USP8 inhibition by the DUBs-IN-2 inhibitor, depletion of endogenous USP8 using two independent sgRNAs or shRNAs resulted in a dramatic upregulation of PD-L1 protein levels in various cancer cell lines including CT26 and DLD1, but did not affect the PD-1 expression level in MOLT4 cells (Fig. 1h–j and Supplementary Fig. 1h–j).