Figure 4.

Targeting of signal transduction and DNA repair enzymes sensitizes PDAC cell cultures to photon and proton irradiation. (A) 3D tumoroid formation capacity of unirradiated Colo357 and MiaPaCa-2 cells 1-h pretreated with indicated pharmacological inhibitors (experimental set-up shown in Figure S2A); (B) Normalized 3D PDAC tumoroid formation capacity upon 1-h inhibitor pretreatment combined with 6-Gy photon or proton irradiation. Data in the order of cell-line-specific inhibitor efficacy after photon irradiation. Enhancement ratio (tumoroid formation capacity after 6 Gy control treatment/tumoroid formation capacity after 6 Gy inhibitor treatment) are indicated as blue triangles; (C) Differences in the radiosensitizing efficacy of inhibitors visualized by Δ values of normalized tumor formation capacity (tumoroid formation capacity after 6 Gy of protons - tumoroid formation capacity after 6 Gy of photons). All results show mean ± SD (n ≥ 2); Δ: delta, i: inhibitor, TF: tumoroid formation.