In terms of clinical trials, the Src inhibitor dasatinib, approved by the FDA for leukemia, has been assessed as first line in combination with trastuzumab plus paclitaxel in HER2 metastatic BC (NCT01306942) with awaited results [175], and as second line alone in HER2 recurrent, locally advanced, or metastatic BC pretreated with chemotherapy (taxane and/or anthracycline, NCT00371345) with poor results. This evidence concerns the gene ERBB2 and leukemia.