Phospho-Akt immunohistochemical expression in UGBM1, U-87MG, and MO59J spheroids following irradiation. Immunostaining score was calculated for non-treated control (■) or 5 Gy irradiated (□) as determined 24 h after treatment. Arbitrary scoring system was calculated as described in Methods section. Data was plotted as the mean ± SD of three different experiments. *Significantly different from control (p < 0.05).