SOX2 Controls Fate of Brain Tumor Cells Figure 6. Characterization of i-SOX2-DAOY medulloblastoma cells. (A) i-SOX2-DAOY cells were exposed to Dox for 24 hours and nuclear extracts were isolated. A Flag-antibody was used to probe a western blot for the expression of flag-epitope tagged SOX2. (B) MTT assay of i-SOX2- DAOY cells after various duration exposure to Dox. Triplicates of each condition tested were averaged, and the error bars represent standard deviations. ‘*’ and ‘**’ indicates statistical significance (p,0.05 and p,0.005, respectively, student’s t-test). (C) Photomicrographs of i-SOX2-DAOY PLOS ONE | www.plosone.org 9 August 2012 | Volume 7 | Issue 8 | e44087