Figure 2.

Lovastatin enhanced the cytotoxicity of TMZ in GBM cells. (a) U87 and U251 cells were treated with different concentrations of TMZ with or without lovastatin (5 μM) for 72 hrs. The IC₅₀ value of TMZ was measured by the MTT assay. Cells treated with TMZ + lovastatin were compared with TMZ alone at each TMZ concentration; N = 3. (b) Colony formation assay. Cells (500 cells/well) were treated with TMZ (200 μM), lovastatin (2.5 μM), or combination for 3 days and then cultivated with fresh medium. The cells were cultivated for 2 weeks in total. Colonies were counted under a light microscope. (c). Quantification of colony formation results; N = 3. ^∗p < 0.05; ^∗∗p < 0.01; ^∗∗∗p < 0.001; ^∗∗∗∗p < 0.0001; ns = no significance.