In addition, the neratinib plus everolimus and neratinib plus fulvestrant combinations were equally effective at suppressing tumor progression in mice bearing ERBB2 mutant xenografts and superior to the single-agents–alone controls23, emphasizing the importance of targeting both the ER and HER2 pathways in ER+/ERBB2-mutant tumors. Here, ESR1 is linked to neoplasm.