Nuclear Control of Mitochondrial Homeostasis and Venetoclax Efficacy in AML via COX4I1

Area of Science:

• Cellular biology
• Molecular oncology
• Mitochondrial function

Background:

• Cell signaling pathways regulate critical cellular functions including communication and metabolism.
• Acute myeloid leukemia (AML) is a hematologic malignancy with complex signaling networks.

Purpose of the Study:

• To identify novel vulnerabilities in AML using a cell signaling-focused CRISPR screen.
• To elucidate the role of COX4I1 in AML pathogenesis and explore therapeutic strategies.

Main Methods:

• CRISPR screening to identify gene dependencies in AML.
• CRISPR gene tiling and mitochondrial proteomics to dissect protein function.
• In vivo studies to assess the impact on leukemia progression.
• Pharmacological inhibition and drug synergy studies.

Main Results:

• Cytochrome c oxidase subunit 4 isoform 1 (COX4I1) was identified as a key vulnerability in AML.
• COX4I1 depletion impaired leukemia cell proliferation and AML progression in vivo.
• Loss of COX4I1 induced mitochondrial stress, ferroptosis, and disrupted oxidative phosphorylation.
• COX4I1 is crucial for mitochondrial Complex IV assembly and function in leukemia cells.
• COX4I1 inhibition synergized with venetoclax, a BCL-2 inhibitor.

Conclusions:

• COX4I1 is a critical mitochondrial checkpoint in AML.
• Targeting COX4I1 presents a promising therapeutic strategy for AML, potentially in combination with venetoclax.
• Understanding COX4I1's role offers new insights into AML biology and treatment.