Figure 3.

Radiation-induced hypomethylation is accompanied by MEK/ERK activation. (A) Meningioma cells were irradiated at 7 Gy and the cell lysates were immunoblotted for different molecules as indicated. (B) The band intensities were quantified and represented as arbitrary units. (C) Meningioma cells were pretreated with U0126 (10 µM) for 30 minutes before radiation treatment and incubated overnight in serum-free medium. Conditioned media were probed for uPA activity, and cell lysates were immunoblotted for different molecules. (D) The band intensities were quantified and represented as arbitrary units. (E) Meningioma cells were pretreated with zebularine (50 µM) for 24 hours, and the cell lysates were immunoblotted for pERK and GAPDH. (F) The band intensities were quantified and represented as arbitrary units. (G) Meningioma cells were pretreated with zebularine (50 µM) for 24 hours, and MTT assays were performed. Each blot/image is representative of three independent experiments, and each column represents a mean of three values (asterisk represents significant value of P < .05).