CEBPA repression by MECOM blocks differentiation to drive aggressive leukemias

T Travis J. Fleming (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) M Mateusz Antoszewski (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) S Sander Lambo (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) M Michael C. Gundry (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) R Riccardo Piussi (1San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy) L Lara Wahlster (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) S Sanjana Shah (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) F Fiona E. Reed (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) K Kevin D. Dong (5Department of Cell Biology, Harvard Medical School, Boston, MA) J Joao A. Paulo S Steven P. Gygi C Claudia Mimoso (6Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA) S Seth R. Goldman (6Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA) K Karen Adelman (Ludwig Center at Harvard, Harvard Medical School) J Jennifer A. Perry Y Yana Pikman K Kimberly Stegmaier (Department of Pediatric Oncology, Dana-Farber Cancer Institute) M Maria N. Barrachina (7Vascular Biology Program, Boston Children’s Hospital, Boston, MA) K Kellie R. Machlus (7Vascular Biology Program, Boston Children’s Hospital, Boston, MA) V Volker Hovestadt A Andrea Arruda (Princess Margaret Cancer Centre, University Health Network) M Mark D. Minden (Princess Margaret Cancer Centre, University Health Network) R Richard A. Voit (1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA) V Vijay G. Sankaran

Abstract

Abstract Acute myeloid leukemias (AMLs) have an overall poor prognosis with many high-risk cases co-opting stem cell gene regulatory programs, but the mechanisms through which these programs are propogated remain poorly understood. The increased expression of the stem cell transcription factor, MECOM, underlies a key driver mechanism in largely incurable AMLs. However, how MECOM results in such aggressive AML phenotypes remains unknown. To address existing experimental limitations, we engineered and applied targeted protein degradation with functional genomic readouts to demonstrate that MECOM promotes malignant stem cell–like states by directly repressing prodifferentiation gene regulatory programs. Remarkably and unexpectedly, a single node in this network, a MECOM-bound cis-regulatory element located 42 kilobase (kb) downstream of the myeloid differentiation regulator CEBPA is both necessary and sufficient for maintaining MECOM-driven leukemias. Importantly, the targeted activation of this regulatory element promotes differentiation of these aggressive AMLs and reduces leukemia burden in vivo. These findings suggest a broadly applicable approach for functionally dissecting oncogenic gene regulatory networks to inform improved therapeutic strategies.

Article Details

Journal Blood
Volume / Issue Vol. 146, Issue 25
Published December 18, 2025
Pages 3019-3035
ISSN 0006-4971
Publisher Elsevier BV

Journal Info

Blood

Elsevier BV

ISSN: 0006-4971 Health Sciences

Authors (24)

T

Travis J. Fleming

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

M

Mateusz Antoszewski

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

S

Sander Lambo

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

M

Michael C. Gundry

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

R

Riccardo Piussi

1San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy

L

Lara Wahlster

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

S

Sanjana Shah

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

F

Fiona E. Reed

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

K

Kevin D. Dong

5Department of Cell Biology, Harvard Medical School, Boston, MA

J

Joao A. Paulo

S

Steven P. Gygi

C

Claudia Mimoso

6Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA

S

Seth R. Goldman

6Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA

K

Karen Adelman

Ludwig Center at Harvard, Harvard Medical School

J

Jennifer A. Perry

Y

Yana Pikman

K

Kimberly Stegmaier

Department of Pediatric Oncology, Dana-Farber Cancer Institute

M

Maria N. Barrachina

7Vascular Biology Program, Boston Children’s Hospital, Boston, MA

K

Kellie R. Machlus

7Vascular Biology Program, Boston Children’s Hospital, Boston, MA

V

Volker Hovestadt

A

Andrea Arruda

Princess Margaret Cancer Centre, University Health Network

M

Mark D. Minden

Princess Margaret Cancer Centre, University Health Network

R

Richard A. Voit

1Division of Hematology/Oncology, Boston Children’s Hospital, Harvard Medical School, Boston, MA

V

Vijay G. Sankaran