Accordingly, the ErbB receptor family with their most prominent members EGFR and HER-2 represent validated targets for anti-cancer therapy, and anti-ErbB monoclonal antibodies (e.g. cetuximab, panitumumab, and trastuzumab) and tyrosine kinase inhibitors (gefitinib, erlotinib, and lapatinib) have now been approved for the treatment of advanced colorectal cancer, squamous cell carcinoma of the head and neck, advanced non-small-cell lung cancer, as well as pancreatic and breast cancer [33]. Here, ERBB2 is linked to breast cancer.