RXRA and chronic myelogenous leukemia, BCR-ABL1 positive: CML cell lines treated with RXRA ligands combined with IM showed a significant increase in cleaved caspase-3 and cleaved PARP expression (Figure 4D) and increased apoptosis combined with IM (Figure 4E) as well as with 2nd generation TKIs, dasatinib and nilotinib (Supplementary Figures S6A, B).