CHD2 Regulates Neuron-Glioma Interactions in Pediatric Glioma

Area of Science:

• Neuro-oncology
• Epigenetics
• Chromatin Remodeling

Background:

• High-grade gliomas (HGG), including diffuse midline glioma (DMG), are aggressive brain tumors.
• Neuronal activity is increasingly recognized as a driver of HGG progression.
• The epigenetic mechanisms linking neuronal activity to HGG pathogenesis are largely unknown.

Purpose of the Study:

• To investigate the role of the chromatin remodeler chromodomain helicase DNA-binding protein 2 (CHD2) in H3.1K27M-mutant DMG.
• To elucidate the epigenetic mechanisms by which CHD2 regulates neuron-glioma interactions and tumor progression.

Main Methods:

• Depletion of CHD2 in H3.1K27M DMG cells.
• In vitro assays assessing cell viability and neuron-glioma synaptic connections.
• In vivo studies evaluating tumor proliferation, calcium transients, and mouse survival.
• Mechanistic studies involving FOSL1 and gene expression analysis.

Main Results:

• CHD2 depletion reduced H3.1K27M DMG cell viability and neuron-glioma synaptic connections in vitro.
• Reduced CHD2 impaired neuron-induced proliferation in vitro and in vivo, and activity-dependent calcium transients in vivo.
• Depletion of CHD2 extended survival in H3.1K27M DMG-bearing mice.
• CHD2, in coordination with FOSL1, regulates axon-guidance and synaptic genes in H3.1K27M DMG.

Conclusions:

• CHD2 is a critical regulator of the H3.1K27M DMG epigenome.
• CHD2 controls gene expression programs that mediate neuron-glioma interactions.
• Targeting CHD2 presents a potential therapeutic strategy for H3.1K27M DMG by disrupting neuron-driven tumor progression.