MT3 and triple-negative breast carcinoma: Furthermore, using the immunohistochemical (IHC) method, MT3 expression was studied in a series of triple-negative breast cancers (TNBC), which are devoid of estrogen (ER) and progesterone (PR) receptors, and human epidermal growth factor receptor-2 (HER-2) expression with regard to patients’ clinical and pathological data.