To corroborate this finding, we analyzed PD-L1 ubiquitination in NSCLC cells and demonstrated that PD-L1 ubiquitination was greatly enhanced in cells transfected with PKP3 shRNA compared with control cells or PKP3-silenced/OTUB1-overexpressing cells (Fig. 6H). This evidence concerns the gene OTUB1 and non-small cell lung carcinoma.