Fig. 2.

Effect of P2X7 receptor (P2X7R) antagonism by Brilliant Blue G (BBG) and oxidized ATP (oATP) on tumour growth in the human U251 glioblastoma cell line (a–d) and human high-grade glioma samples (e–h). U251 glioma cells and cultured human glioma samples were treated with the P2X7R antagonists, Brilliant Blue G (BBG; 20 μM) and oxidized ATP (oATP; 250 μM). Cells were stained with DAPI nuclear stain and fixed 72 h post-treatment. Human tumour samples were pre-stained with glial fibrillary acidic protein (GFAP) for identification of tumour cells. A manual cell count was conducted thereafter, and the mean cell count was generated from a total of 16 random fields per treatment. The magnitude of change was measured using the ratio of cells in the each group compared with that of the average cell count of the control group. a U251 cell count data. There was no significant reduction in tumour cell numbers between cells treated with BBG and oATP and the control; n = 12, one-way ANOVA, p = 0.0643. Data are represented as mean ± SEM. Example U251 cell count images are provided for b control, c BBG and d oATP. e Human glioma sample cell count data. There was no significant reduction in tumour cell numbers between cells treated with BBG and oATP and the control; n = 5, one-way ANOVA, p = 0.284. Cell counts were expressed as the ratio of treated cells to the control to account for any variability in initial culture cell numbers between tumours. Data are represented as mean ± SEM. Example human glioma sample cell count images are provided for f control, g BBG and h oATP. Scale bar = 5 μM