Given that β-catenin was able to stabilize and upregulate PD-L1 through inducing STT3 isoforms (including A and B isoforms) in breast and colon cancers [32, 64], we therefore examined the roles of STT3 isoforms in spermine-induced PD-L1 N-glycosylation. This evidence concerns the gene CD274 and malignant colon neoplasm.