Medulloblastoma stem cell programs: Molecular roadmaps of disease progression

Over the last decade, an unprecedented number of sequencing studies have characterized the molecular landscape of pediatric brain cancers, including the highly heterogeneous tumor medulloblastoma (MB). Extensive MB profiling has enabled a much deeper understanding of the primitive neurodevelopmental programs that are hijacked during tumor progression. However, we have yet to successfully target and fully eradicate the putative stem and early progenitor cells that drive MB tumorigenesis. This goal will require better human models that faithfully recapitulate oncogenic events, a deeper understanding of the mechanisms governing cell fate decisions in the primary and metastatic compartments, and comprehensive validation studies of MB stem/progenitor cell molecular signatures extracted from bioinformatics datasets. In this perspective, we summarize the current knowledge of the developmental origins of MB and highlight the unmet needs pertaining to tumor modeling, characterization of molecular programs driving metastatic cells, and post-transcriptional regulation of cell fate.