Abemaciclib Is Effective in Palbociclib-Resistant Hormone Receptor-Positive Metastatic Breast Cancers

The authors generated multiple in vitro models of palbociclib-resistant and abemaciclib-resistant cell lines, as well as in vivo patient-derived xenografts and ex vivo PDX-derived organoids from patients who progressed on cyclin-dependent-kinase-4/6 inhibitor.