Fig. 1.

Sodium sulfide is cytotoxic to GBM but not human cerebral microvascular endothelial cells. Cells were treated with Na₂S for 4 h with media change and replacement at 2 h (A). The dose response of T98G and U87 cells to Na₂S was determined using clonogenic survival. The dashed green line indicates the position of Surviving Fraction = 1 on the graph. Data was analyzed using a one-way ANOVA with Tukey's post-hoc analysis (B). Free sulfide levels were measured after the 4 h treatment with 476 μM Na₂S using HPLC. Data was analyzed using a Student's t-test comparing 0 and 476 μM for each cell line (C). The effect of 476 μM Na₂S on hCMEC/D3 was also determined using clonogenic survival. Data was analyzed using a Student's t-test comparing 0 and 476 μM (D). All data are from 3 independent experiments. Error bars represent SD and * represents P < 0.05. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)