The human GBM orthotopic xenograft exhibiting invasive and extensive infiltration in NOD-scid mice. The nestin-expressing NSC-like GBM cells are highly invasive, showing diffuse infiltration into the brain including the corpus callosum, hippocampus, and the subependymal regions. (a, b) Photomicrographs of low-power field of human GBM orthotopic xenograft in NOD-scid mouse brain. (c, d) Photomicrographs of high-power field of corpus callosum infiltrated by human GBM. (e, f) Photomicrographs of high-power field of mass lesion of human GBM. (a, c, e) Hematoxylin and eosin staining. (b, d, f) Immunohistochemistry for nestin. Scale bars in (a) and (b), 500 μm; scale bars in (c), (d), (e), and (f), 100 μm.