The same compounds were then assayed at a single concentration of 30 μM (we initially expected that, having designed the compounds to bind to P2X4, they would likely be less potent at P2X7, and need to be applied at a higher concentration to observe an effect) on 1321N1 astrocytoma cells stably expressing human P2X7. This evidence concerns the gene P2RX7 and astrocytoma (excluding glioblastoma).