Besides, Dex decreases DOT1L expression in Dex‐sensitive B‐lymphoma cells and MLL‐rearranged leukemia cells, but not in Dex‐insensitive acute monocytic leukemia cells, suggesting that DOT1L may be an underlying novel indicator of Dex sensitivity against hematological malignancies. The gene discussed is KMT2A; the disease is leukemia.