The XPO7-NPAT axis represents key vulnerabilities in TP53-mutated acute myeloid leukemia

Area of Science:

• Hematology
• Molecular Biology
• Cancer Research

Background:

• Acute myeloid leukemia (AML) with TP53 mutations presents a significant therapeutic challenge due to its resistance to conventional treatments.
• The urgent need for novel strategies is highlighted by the poor clinical outcomes associated with this AML subtype.

Purpose of the Study:

• To identify novel therapeutic targets for TP53-mutated AML.
• To elucidate the molecular mechanisms driving the survival and proliferation of TP53-mutated AML cells.

Main Methods:

• Genome-wide CRISPR/Cas9 dropout screens in isogenic mouse AML models (Trp53-wild-type and knockout).
• Transcriptomic and proteomic analyses of mouse and human AML samples.
• Validation using patient-derived xenograft (PDX) models and analysis of public AML datasets.

Main Results:

• The XPO7 (exportin 7)-NPAT (nuclear protein, coactivator of histone transcription) pathway was identified as essential for TP53-mutated AML survival.
• In TP53-mutated AML, XPO7 promotes proliferation by retaining NPAT in the nucleus, leading to histone loss and genomic instability.
• Elevated XPO7 and NPAT expression is characteristic of TP53-mutated AML and drives leukemia progression in vivo.

Conclusions:

• The XPO7-NPAT pathway is a critical driver of TP53-mutated AML pathogenesis.
• This pathway represents a significant vulnerability and a promising therapeutic target for refractory TP53-mutated AML.