Figure 1

Luciferase activity in GL261.luc cells. U87MG cells, previously modified with the same lentivirus used here for GL261 modification [14], were used as a control for assessing luciferase activity in transduced GL261 cells. U87MG.luc cells were plated at densities of 1x10⁶, 0.5x10⁶, 0.25x10⁶, 0.1x10⁶, 0.05x10⁶, and 0.025x10⁶ cells/well, from left to right. GL261 (negative control) and GL261.luc cells were plated at densities of 1x10⁶, 0.5x10⁶, and 0.25x10⁶ cells/well.