ERBB2 and breast cancer: Triple-negative BC (TNBC), a BC subtype that lacks the expression of hormone receptors (ER-a and PR) and ErbB2/HER2 [8,9,10,11,12], is notoriously known for its aggressiveness and lethality because of its high metastatic and recurrence potentials, coupled with the lack of FDA-approved targeted therapies that could be effective against this BC subtype.