These variants include single mutated PD-L1 at each of its four N-glycosylation sites, and a fully non-glycosylated PD-L1; the WT and mutated PD-L1 variants were overexpressed in two cellular systems (human TNBC MDA-MB231 cells and human MCF7 luminal-A ER+ breast tumor cells), and were co-cultured with PD-1 biosensor cells - designated Immune Checkpoint Artificial Reporter overexpressing PD-1 (IcAR-PD-1) [33, 34] - to assess the functional bioavailability of these PD-L1 glycosylation mutants. This evidence concerns the gene PDCD1 and breast neoplasm.