Targeting integrated epigenetic and metabolic pathways in lethal childhood PFA ependymomas

Area of Science:

• Neuro-oncology
• Epigenetics
• Cancer Metabolism

Background:

• Childhood posterior fossa group A ependymomas (PFAs) have poor prognoses and limited treatments.
• PFAs overexpress EZHIP, reducing repressive histone H3 lysine 27 trimethylation (H3K27me3).
• EZHIP-driven epigenetic changes are linked to altered cellular metabolism.

Purpose of the Study:

• To investigate the metabolic landscape of PFAs.
• To explore the role of EZHIP in regulating cancer metabolism.
• To evaluate the therapeutic potential of targeting metabolic pathways in PFAs.

Main Methods:

• Integrated metabolic analyses of patient-derived cells and tumors.
• Single-cell RNA sequencing of tumors.
• Noninvasive metabolic imaging and in vivo/in vitro xenograft models.
• Treatment with metformin, an AMP-activated protein kinase (AMPK) activator.

Main Results:

• PFAs exhibit enhanced glycolysis and tricarboxylic acid (TCA) cycle metabolism, correlated with poor outcomes.
• EZHIP overexpression in PFAs and mouse models is associated with increased histone H3 lysine 27 acetylation (H3K27ac) at metabolic genes.
• Metformin reduced EZHIP, increased H3K27me3, suppressed TCA cycle metabolism, and demonstrated therapeutic efficacy in PFA models.

Conclusions:

• PFAs are characterized by enhanced glycolysis and TCA cycle metabolism, driven by EZHIP.
• Targeting integrated metabolic and epigenetic pathways, such as with metformin, offers a promising therapeutic strategy for childhood ependymomas.