The higher expression levels of IL33 in human DIPGs and pediatric cortical HGG samples are consistent with the IL33 data in adult HGGs.26–28 Since cellular resolution is lacking, the source of IL33 in DIPGs may be the microenvironment, as our data suggests, while in the cortical HGGs, the source could be the glioma cells, as has been shown for adult HGGs.26,27. This evidence concerns the gene IL33 and central nervous system cancer.