Fig. 4

Joint analysis of clonogenic survival in all three cell lines after combined treatment with 5-aza-dC, IR, and a) VPA, b) SAHA, c) ATRA, d) ABC, e) RES . Relative data (untreated, nonirradiated control = 1) are presented as mean ± SEM, n = 3. Statistical significance is presented vs. control (0, 2 or 8 Gy, black bars) by asterisks (*, p ≤ 0.05; **, p ≤ 0.01; ***, p ≤ 0.001) and for multimodal combination (white bar) vs. 5-aza-dC + control (dark grey bar) by hash (#, respectively) to clarify (1) the effects compared to irradiation alone and (2) the enhancement of the previously described effect of 5-aza-dC/IR [4]. Additional information about significant synergism/additivity is given in Table 2. Drug concentrations are shown in Table 1