PRDX4 and invasive breast carcinoma: We next analyzed the associations between PRDXs mRNA expression and RFS of BrCa patients and found that high mRNA expression of PRDX1 (HR = 1.31, 95% CI: 1.17–1.46, P < 0.001), PRDX2 (HR = 1.30, 95% CI: 1.17–1.45, P < 0.001), PRDX4 (HR = 1.54, 95% CI: 1.38–1.72, P < 0.001), PRDX5 (HR = 1.21, 95% CI: 1.04–1.42, P = 0.015) and PRDX6 (HR = 1.20, 95% CI: 1.08–1.34, P < 0.001) were significantly associated with shorter relapse-free survival (RFS) of BrCa patients, while high mRNA expression of PRDX3 was notably related to favorable RFS of BrCa patients (HR = 0.81, 95% CI: 0.72–0.90, P < 0.001).