Fourteen proteins (ANXA1, ANXA2, AZU1, C3, CD14, ELANE, FGG, GRN, IGHG1, LTF, MPO, RNASE2, SERPING1, SPP1) from PCa vs. BPH dataset and 17 proteins (ANXA1, APOA1, APOH, AZU1, C3, C4A, CD14, ELANE, F2, FGG, GRN, IGHG1, KNG1, RNASE2, S100A9, SPP1, UMOD) from PCa vs. BC dataset are involved in this subcategory. The gene discussed is S100A9; the disease is benign prostatic hyperplasia.