Fig. 2. Sensitivity of the GL26 glioma cell line to TMZ and IFN-β. A : The viability of glioma cells was analyzed via MTT assay 24 h, 48 h, and 72 h after TMZ (0-500 µM) treatment. B : The number of viable cells was counted 72 h after the GL26 cell line was treated with MSC-IFN-β alone and in combination with TMZ (20 µM, which was selected as subtoxic dose). The results are representative of two independent experiments. All data are represented as the mean±SEM. ^*p<0.05, Student's t-test. Points, mean; bars, SEM. TMZ : temozolomide, IFN-β : interferon-bata, MSC-IFN-β : MSCs to secret mouse IFN-β, SEM : standard error of the mean, MTT : 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.