Figure 2

Forms of glioblastoma cell death after fractionated RT and/or CT with TMZ and/or VPA. T98G (A), U251MG (B), or U87MG (C) tumor cells were treated with TMZ (20 μM) and/or VPA (0.5 mM) alone, or in combination with 5 daily radiation doses of 2Gy. Forty-eight hours after the last treatment, cells were stained with AnxA5-FITC/PI and cell death was analyzed by flow cytometry. The percentages of apoptotic, primary, or secondary necrotic tumor cells are displayed. Pooled results of four independent experiments are shown, each performed at least in triplicates. Mean values (±SD) are displayed. Gy, Gray; RT, radiotherapy; CT, chemotherapy; w/o, untreated control; TMZ, temozolomide; VPA, valproic acid; 1°, primary; 2°, secondary; ## P < 0.01, ### P < 0.001 (against w/o), *P < 0.05, ***P < 0.001 (against RT), §§ P < 0.01, §§§ P < 0.001 (TMZ ± RT against VPA + TMZ ± RT), + P < 0.05, +++ P < 0.001 (VPA ± RT against VPA + TMZ ± RT).