ERBB2 and breast cancer: We demonstrated the transcriptional adaptive response to trametinib inhibition of the MEK-ERK pathway in TNBC patient tumors and in HER2+ breast cancer patients in response to current standard-of-care anti-HER2 therapies (trastuzumab, pertuzumab, trastuzumab + pertuzumab, and trastuzumab + lapatinib) (47).