KRASG13D-positive cells show delayed repair kinetics of DSBs. (A) (Left) CCRF-HSB2 cells and (right) U-937 cells transduced with either EV or pLenti6.2-KRASG13D were irradiated with 10 Gy. Cells were stained with anti-γH2AX-Alexa488 and DAPI at the indicated time points. Graphs show the percentage of cells with >5 γH2AX foci (200 cells per experiment were analyzed). Shown are the mean values ± SD of 3 independent experiments (*P < .05, **P < .01, ***P < .001, Student t test). (B) Nomo-1 cells transduced with either (left) nonsilencing miR-shRNA (sh ctrl) or (right) KRAS-miR-shRNA (sh KRAS) were irradiated with 10 Gy. Cells were stained with anti–γH2AX-Alexa488 and DAPI at the indicated time points. Graphs show the percentage of cells with >5 γH2AX foci. Data represent mean values ± SD of 3 independent experiments (***P < .001, Student t test). (C) (Left) CCRF-HSB2, (right) U-937, and (D) Nomo-1 cells (± doxycyline treatment) were irradiated with 10 Gy and repair kinetics of induced DSBs were determined by the neutral comet assay at different time points following irradiation. Data represent the mean of ≥3 independent experiments ± SD (*P < .05, **P < .01, ***P < .001, Student t test).
