Using genetically engineered mouse models to understand low-grade glioma development and growth in children

Pilocytic astrocytoma (PA) is the most common brain tumor observed in children. These tumors can form sporadically in children with no underlying genetic disease or in 15-20% of children with neurofibromatosis type 1 (NF1), an inherited cancer predisposition syndrome. Though similar histologically, the genetic basis for PA formation in these two populations are distinct. In the general population, PAs likely arise in response to aberrant BRAF activation, whereas in the context of NF1, they result from bi-allelic inactivation of the NF1 tumor suppressor gene. Since accurate rodent models of sporadic PA are currently under development, Nf1 genetically engineered mouse models have served as tractable systems to study the role of aberrant intracellular signaling, nonneoplastic cells in the tumor microenvironment, and genomic modifiers on gliomagenesis. These small-animal models have also been used as platforms to discover next-generation targeted therapies and to evaluate the efficacy of these potential anticancer treatments prior to clinical trials for NF1-associated astrocytomas.