Figure 7.

Relative biological effectiveness (RBE) values ± SEM for G0/G1-phase normal NFF28 primary fibroblasts (A) and asynchronously growing A549 lung carcinoma (B), U2OS osteosarcoma (C), and U87MG malignant glioma cells (D) pretreated for 18 h with 10 µM SAHA, 10 µM M344, and 5 µM PTACH and irradiated 200 MeV protons, 290 MeV/n C-12 ions, or 350 MeV/n O-16 ions compared to respective DMSO control or HDACi-pretreated cultures exposed to reference cesium-137 γ-rays [calculated using D₁₀ survival values; asterisks mark significant differences at p-values of ≤0.05 (*), ≤0.01 (**), ≤0.001 (***), and ≤10⁻⁴ (****) by two-way ANOVA].