GFAP and glioblastoma: Although the differences in hcast 3-25-V5 transcript levels between the two GBM cultures (hcast 3-25-V5 mRNA was increased 6.4-fold in GBM3 and 58.52-fold in GBM5 compared to respective empty-V5 controls), transient overexpression of hcast 3-25-V5 did not affect the transcription of the other calp/cast system components, GFAP and SOX2, as observed in 15-days-serum differentiated GBM3 and GBM5 cells.