TG02 induces cell death and synergizes with TMZ in GBM. A and B, TG02 inhibits cell growth in both MGMT high-expressing (A, plots a–d) and MGMT low-expressing cells (B, plots a–d). Cell viability was determined after treatment with vehicle, TG02, TMZ, or TG02/TMZ for 72 hours. C and D, Combined TG02/TMZ treatment has a synergistic antiglioma effect in GSC923 (C) and GSC827 cells (D). Dose-response curves (plot a) were plotted from the cell viability following 72 hours of treatment. The synergistic effects of TG02/TMZ in the cells were determined by CI in b. CI values were calculated by COMPUSYN software and are shown in c. CI < 1 is a synergistic, CI = 1 is an additive, and CI > 1 is an antagonistic effect of the two compounds combined (20). **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.