St. Jude researchers identify cause of region-specific pediatric brain tumors

Researchers at St. Jude Children's Research Hospital have identified why diffuse midline glioma (DMG), a pediatric brain cancer, develops specifically in the midline regions of the brain. The study, published in Nature Communications, focuses on the H3.3 K27M mutation in the histone H3.3 protein, which is a primary driver of these tumors.

While this mutation can affect DNA packaging in cells throughout the body, it appears to provide a selective advantage that drives cancer almost exclusively in midline structures like the brainstem, thalamus, and spinal cord. To investigate this, scientists compared oligodendrocyte precursor cells (OPCs) from the brainstem, where tumors frequently occur, to those from the telencephalon, where they rarely form. The findings suggest that the location and intrinsic differences in how these cells respond to the mutation shape the formation of DMG.