FIGURE 4.

Cell of origin for each subgroup of medulloblastoma. The upper figure shows the sagittal view of the embryonic cerebellum with the stages of cell differentiation in the cerebellum. Black arrows demonstrate the differentiation process. The lower figure shows the common location of each medulloblastoma subgroup in the axial image of the cerebellum. The location of the precursors that likely give rise to each medulloblastoma subgroup is indicated by the dashed arrows. EGL, external granule layer; GCP, granule cell precursor; RL, rhombic lip; SVZ, subventricular zone; UBC, unipolar brush cell; VZ, ventricular zone