GFAP and neoplasm: The majority of EGFR(+)/TP53(+)/GFAP(+) cells from early spheroid transfers were BrdU-positive (Fig. 4E); after 10 weeks less than 50% of cells incorporated BrdU (Fig. 4F); and finally, tumor cells isolated from glioblastoma became non-proliferative in 3D conditions as well.