At the end, we found one 36-gene combination from the 415 genes, whose protein concentration level could be the most distinguishing between breast and other cancers: MAPKAPK2, PARP1, CCT3, VAV3, AEBP1, KDM5B, NPNT, TMED3, NEBL, STAT1, POGK, ATP2A3, FKBP4, ABHD2, EFNA1, PRSS8, CALR, LUM, MAZ, PDXDC1, SPINT1, REPS2, CREB3L4, PGK1, KIAA1522, SIPA1L3, GBP5, TTLL12, ZNF217, ARNT2, FOXRED2, ALDH18A1, RSAD2, TGFB3, PCK2 and SERPINA3, with detailed prediction data given in S6 Table. Here, PGK1 is linked to cancer.