AZD8055 has been shown to inhibit cell proliferation in several solid tumors [12,13] and to sensitize tumor cells to chemotherapies [14,15,16]; however, AZD8055 could also initiate the unexpected activation of phosphatidylinositol 3-kinase (PI3K)/AKT and of certain receptor tyrosine kinases (RTKs), such as HER3 or IGF-1R, in breast cancer or non-small cell lung cancer (NSCLC) cells [17,18]. This evidence concerns the gene ERBB3 and breast cancer.