Specifically, USP14 downregulates PD-L1 in pancreatic cancer by removing K63-linked ubiquitination at Lys280, thereby enhancing antitumour immunity [148], while USP8 stabilises PD-L1 through deubiquitination to promote immune suppression [149]—highlighting the functional dichotomy of DUBs in PD-L1 regulation, which may depend on tumour context or substrate modification patterns. This evidence concerns the gene CD274 and familial pancreatic carcinoma.