BTG2 and medulloblastoma: Moreover, <i>PC3</i>/<i>Tis21</i>/<i>BTG2</i> inhibits medulloblastoma onset by promoting the migration and differentiation of cerebellar precursor cells outside the external granular layer, i.e., the proliferative epithelium of the cerebellum, thus diminishing their susceptibility to oncogenic transformation under the influence of Sonic Hedgehog.