HK3 and neoplasm: Notably, shHK3 suppressed both basal levels and UDP-GlcNAc-elevated PD-L1 and O-GlcNAcylation (Fig. 3J, K), demonstrating that the elevated basal level of tumor HK3, in addition to UDP-GlcNAc-induced HK3, both contributed to PD-L1 expression upon UDP-GlcNAc stimulation.