The combined analysis of OS, time-dependent ROC, and the PPI network revealed that the genes of the top 3 GO terms of the upregulated DEGs from the high vs. low immune score groups were associated with better prognosis in breast cancer, and 15 of them were related to good prognosis in breast cancer, especially CD226 and KLRC4-KLRK1. The gene discussed is KLRK1; the disease is breast cancer.