Fig. 6: Changes in P2X7A and P2X7B isoform expression and cholesterol content in radiation-resistant GBM clones during recovery.

a mRNA expression levels of P2X7A and P2X7B isoforms in GB40 cells at increasing intervals radiation treatment. Data were normalized to HPRT-1 and GAPDH housekeeping genes. Data are shown as mean ± SEM; n = 3. b mRNA expression levels of P2X7A and P2X7B isoforms in GB48 cells at increasing intervals after radiation treatment. Data were normalized to HPRT-1 and GAPDH housekeeping genes. Data are shown as mean ± SEM; n = 3. c, d Total cellular cholesterol content measured at increasing intervals after radiation treatment. Single data are reported, n = 2. e, f Correlation between P2X7A/B mRNA expression levels, DNA damage (expressed as percent tail DNA), senescence marker (expressed as percent β-gal positive cells), and the total amount of cholesterol at increasing intervals after radiation treatment. Statistical analyses were conducted with unpaired two-tailed Student’s t-test. P values: *P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001; ****P ≤ 0.0001; ^##P ≤ 0.01; ^###P ≤ 0.001.