Epidermal growth factor receptor (EGFR/ErbB1), is onemember of this family, over expressed in 20% to 80% of breast cancers [2, 3], and another member is HER2 (ErbB2/neu), is amplified and/or over expressed (i.e., HER2-positive) in 20%to 30% of breast cancers [4, 5]. Here, ERBB2 is linked to breast cancer.