Epigenetic downregulation of Socs2 contributes to mutant N-Ras-mediated hematopoietic dysregulation.
Dis Model Mech
; 15(5)2022 05 01.
Article
em En
| MEDLINE
| ID: mdl-35352806
ABSTRACT
RAS mutations occur in a broad spectrum of human hematopoietic malignancies. Activating Ras mutations in blood cells leads to hematopoietic malignancies in mice. In murine hematopoietic stem cells (HSCs), mutant N-RasG12D activates Stat5 to dysregulate stem cell function. However, the underlying mechanism remains elusive. In this study, we demonstrate that Stat5 activation induced by a hyperactive Nras mutant, G12D, is dependent on Jak2 activity. Jak2 is activated in Nras mutant HSCs and progenitors (HSPCs), and inhibiting Jak2 with ruxolitinib significantly decreases Stat5 activation and HSPC hyper-proliferation in vivo in NrasG12D mice. Activation of Jak2-Stat5 is associated with downregulation of Socs2, an inhibitory effector of Jak2/Stat5. Restoration of Socs2 blocks NrasG12D HSC reconstitution in bone marrow transplant recipients. SOCS2 downregulation is also observed in human acute myeloid leukemia (AML) cells that carry RAS mutations. RAS mutant AML cells exhibited suppression of the enhancer active marker H3K27ac at the SOCS2 locus. Finally, restoration of SOCS2 in RAS mutant AML cells mitigated leukemic growth. Thus, we discovered a novel signaling feedback loop whereby hyperactive Ras signaling activates Jak2/Stat5 via suppression of Socs2.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Leucemia Mieloide Aguda
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Genes ras
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Neoplasias Hematológicas
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Epigênese Genética
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Proteínas Supressoras da Sinalização de Citocina
Limite:
Animals
Idioma:
En
Revista:
Dis Model Mech
Ano de publicação:
2022
Tipo de documento:
Article