Notably, when compared to adjacent or normal tissues, PRDX1, PRDX2, PRDX4 and PRDX5 were significantly up-regulated expression in several cancer types (UCEC, READ, BLCA, BRCA, CHOL, COAD, LIHC, THCA), while PRDX3 and PRDX6 were down-regulated expression in kidney cancers (Fig. 1B, Additional file 1: Figure S1). Here, PRDX4 is linked to cancer.