Figure 3

Gefitinib treatment disrupts high-speed burst behavior selectively among tumor cell populations within EGFR-amplified glioblastoma. (A–D). Topography graphs of instantaneous tumor cell speed over time, where rows represent individual cells. For all treated samples (n = 6) cells were tracked every 11 minutes and ordered by increasing standard deviation of instantaneous speed. Peak height and color-coded heat-map shading both represent cell speed, representative data from GBM-5 and GBM-8 are shown. Gefitinib treatment (10 μM) for 11 hours, resulted in a qualitative decrease in high-amplitude peaks in an EGFR-amplified slice (GBM-8, A,C). Non-significant changes were observed after treatment of a non-amplified tumor slice (GBM-5, B,D). (E) Movements per hour (i.e. peaks/hr) did not change between control (DMSO, black bars) and gefitinib (grey bars) treatment in pooled cell populations from all EGFR-amplified or non-amplified tumors (p > 0.05, n = 3 amplified tumors, n = 3 non-amplified tumors). (F–H) High-speed movements, standard deviation of instantaneous speed, and distance traveled by the cell per movement were significantly decreased in EGFR-amplified tumors (n = 3, p < 0.05), with no effect in non-amplified tumors (n = 3, p > 0.05). Error bars represent standard error of the mean (SEM).