Article

PML-RAR alpha and Dnmt3a1 Cooperate in vivo to Promote Acute Promyelocytic Leukemia

Institute for Regeneration Medicine, University of California, San Francisco, California 94143, USA.
Cancer Research (Impact Factor: 9.28). 11/2010; 70(21):8792-801. DOI: 10.1158/0008-5472.CAN-08-4481
Source: PubMed

ABSTRACT The PML-RARα oncogene is the central effector of acute promyelocytic leukemia (APL). PML-RARα physically interacts with epigenetic-modifying enzymes including DNA methyltransferases (Dnmt) to suppress critical downstream targets. Here, we show that increased expression of Dnmt3a1 cooperates with PML-RARα in vivo to promote early lethality secondary to myeloid expansion and dysfunction in primary mice. Bone marrow cells from these mice cause leukemogenesis with a shortened latency and a higher penetrance on transplantation into irradiated recipients. Furthermore, leukemic cells overexpressing PML-RARα and Dnmt3a1 display increased methylation at a target promoter compared with PML-RARα or Dnmt3a1 controls. Our findings show a cooperation between the PML-RARα oncogene and the Dnmt3a1 enzyme in vivo and that Dnmt levels can be rate limiting in APL progression.

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Available from: Haijiang Lin, Jun 03, 2015
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