Research Paper Volume 12, Issue 17 pp 16759—16774
HDAC4 inhibition disrupts TET2 function in high-risk MDS and AML
- 1 Department of Hematology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou 310016, China
- 2 Department of Hematological Malignancies Translational Science, Gehr Family Center for Leukemia Research, Hematologic Malignancies and Stem Cell Transplantation Institute, Beckman Research Institute, City of Hope Medical Center, Duarte, CA 91010, USA
- 3 The Integrative Genomics Core, Beckman Research Institute, City of Hope Medical Center, Duarte, CA 91010, USA
- 4 Department of Hematology and Hematopoietic Cell Transplantation (HCT), Beckman Research Institute, City of Hope Medical Center, Duarte, CA 91010, USA
Received: April 3, 2020 Accepted: June 9, 2020 Published: July 29, 2020https://doi.org/10.18632/aging.103605
How to Cite
Copyright: © 2020 Huang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Aberrant DNA methylation often silences transcription of tumor-suppressor genes and is considered a hallmark of myeloid neoplasms. Similarly, histone deacetylation represses transcription of genes responsible for cell differentiation/death. A previous clinical study suggested potential pharmacodynamic antagonism between histone deacetylase inhibitors (HDACi) and DNA hypomethylating agents (HMA). Herein, to determine such antagonism, we used MDS/AML lines and NHD13 transgenic mice, and demonstrated that treatment with the pan-HDACi suberoylanilide hydroxamic acid (SAHA) significantly decreased TET2 expression and global 5-hydroxymethylcytosine (5hmC) levels. Mechanistically, our RNAi screen revealed that HDAC4 was responsible for maintaining TET2 levels. Accordingly, HDAC4 knockout reduced expression levels of MTSS1, a known TET2 target, an event associated with decreased 5hmC enrichment on the MTSS1 enhancer. Retrospective analysis of GEO datasets demonstrated that lower HDAC4 levels predict worse prognosis for AML patients. In an MDS-L xenografted immunodeficient mouse model, vitamin C co-treatment prevented TET2 loss of activity seen following SAHA treatment. Accordingly, vitamin C co-treatment further reduced MDS-L cell engraftment relative to SAHA alone. In summary, our findings suggest that co-administration of a TET2 agonist with pan-HDACi treatment could effectively counter potential diminution in TET2 activity resulting from pan-HDACi treatment alone, providing a rationale for evaluating such combinations against high-risk MDS/AML.