COPS5 and colorectal carcinoma: At the PTM level, COP9 signalosome complex subunit 5 (CSN5) and CKLF Like MARVEL Transmembrane Domain Containing 6 (CMTM6) had been proven to lead to the accumulation of PD-L1 via the ubiquitin/proteasome pathway in CRC, which was meaningful for the activity of CD8+ T cells.44 45 Overall, our discovery of the effects of miR-15b-5p, combined with the PTM mediators of PD-L1, provided potential explanations for why the clinical significance of PD-L1 protein is not consistent with that of its mRNA in MSS CRC.