Molecular Basis of Pediatric Brain Tumors.

Brain tumors emerge as the second commonest type of pediatric solid tumors following hematologic malignancies. Genomic profiling of low- and high-grade gliomas, ependymomas and medulloblastomas has revealed chromosomal abnormalities and specific gene mutations which have been associated with aberrant activation of crucial signal transduction pathways, including mitogen-activated protein kinase, mammalian target of rapamycin and retinoblastoma tumor suppressor signaling. Furthermore, pediatric high-grade gliomas are associated with chromatin remodeling defects and somatic histone gene mutations that affect prognosis. This review provides an update of the molecular and genetic alterations that characterize pediatric brain tumors, and discusses novel therapeutic approaches targeting these abnormalities.