We found 33 IgSF genes (KIT, PDGFRB, KDR, FGFR1, CD28, NTRK1, etc.)that were themselves breast cancer driver genes as well as 250 IgSF genes (including PTPN11, LCK, GRB2, ABL1, APP, etc. Supplementary Table S2) that associated with the breast cancer driver genes. Here, CD28 is linked to breast cancer.