ENL mutation and AML: a new model that reveals oncogenic condensate's function in leukemogenesis

Area of Science:

• Molecular Biology
• Cancer Biology
• Epigenetics

Background:

• Precise gene expression is vital for organism development and homeostasis.
• Transcriptional regulatory proteins form dynamic condensates, and their dysregulation is linked to cancers like AML.
• Mutations in the eleven-nineteen-leukemia (ENL) protein form condensates at genomic targets, but their oncogenic role is unclear.

Purpose of the Study:

• To investigate if ENL mutations drive tumorigenesis through condensate formation.
• To determine the correlation between ENL condensate formation and its oncogenic function in AML.

Main Methods:

• Utilized a conditional knock-in mouse model to study ENL YEATS domain mutations.
• Examined condensate formation in hematopoietic stem/progenitor cells at specific genomic loci (Meis1, Hoxa).
• Disrupted condensate formation via mutagenesis and used small-molecule inhibitors targeting acetyl-binding activity.

Main Results:

• ENL YEATS domain mutation was confirmed as an oncogenic driver for AML.
• Mutant ENL formed condensates at leukemogenic gene loci, impacting chromatin and oncogenic function.
• Inhibiting acetyl-binding activity displaced ENL condensates and impaired AML onset and progression in vivo.

Conclusions:

• ENL condensate formation is crucial for its oncogenic activity in AML.
• Targeting ENL condensate formation represents a potential therapeutic strategy for AML.