IL2 and breast cancer: To validate the prognostic value of GPI-anchored biosynthesis related genes in BC, we develop a gene signature (GPIS) based on 21 GPI-anchored biosynthesis related genes and the characteristic factors of T cell exhaustion (TNF, IL-2, IFN-γ).The Metabric dataset, with its high number of patients, served as the training set, while the TCGA cohort, with its low number of samples, served as the validation set.