High GPx2 expression levels were associated with poorer prognosis in non-small cell lung cancer, glioblastoma, castration-resistant prostate cancer and nasopharyngeal carcinoma [5, 7, 9, 10], while the opposite trend was observed in breast cancer, esophageal squamous cell carcinoma and bladder cancer [8, 11, 12]. This evidence concerns the gene GPX2 and breast carcinoma.