Figure 4

EGF/FGF-dependence of γIR-induced H2AX-phosphorylation and of apoptosis. A. Differentiated GBM8 FBS cultures pretreated or not for 16 h with EGF plus FGF-2 were irradiated with 10 Gy and analyzed for γH2AX levels by Western blotting (upper left); quantification using Image Quant TL (upper right). Expression levels of the stem-cell and progenitor markers Sox2 and musashi were determined to assess the differentiation status of the cells (lower). B. GBM8 FBS cultures treated as in A were analyzed for apoptosis (left) and proliferation (right). C. GBM4 SLGCs either treated or not with EGF plus FGF-2 for 72 h were irradiated with 10 Gy and analyzed for γH2AX-levels by Western blotting (upper left); quantification (upper right). Expression levels of the stem- and progenitor markers Sox2 and musashi were determined to assess the differentiation status of the cells (lower). D. GBM4 SLGCs treated as in C were analyzed for apoptosis (left) and proliferation (right). Representative Western blots are presented. In the other graphs, the mean ± S.D. of three experiments is shown; asterisk, = p < .05.