Combination of HDAC inhibitors with tamoxifen is implicated in reversing tamoxifen/aromatase inhibitor-resistance in ER-positive breast cancers and HDAC inhibitors were shown to increase the sensitivity of cells to BRD4 inhibition for blocking cell growth and promoting apoptosis in leukemia and lymphoma to [59-61]. The gene discussed is BRD4; the disease is leukemia.