Fig. 3: The MET S1016A mutation radiosensitizes cells in vitro and in vivo.
From: A DNA-PK phosphorylation site on MET regulates its signaling interface with the DNA damage response
A–C Analysis of the radiosensitivity of the MT, SAMT, YH and SAYH cell lines upon irradiation at the indicated doses with the crystal violet (proliferation), resazurin blue (viability) and Live/Dead assays, respectively. The SA mutation radiosensitizes cells expressing active MET. D Tumor growth (relative to size on day of treatment) of subcutaneous mouse xenografts from MT and SAMT cells upon irradiation (see Fig. S7 for a comparison with non-irradiated animals). E Comet assay analysis of DNA damage in the MT, SAMT, YH and SAYH cell lines, immediately (“short”) or 2 h after irradiation (10 Gy). The SA mutation has no impact on the amount of DNA damage received upon irradiation and does not prevent return to basal levels. F γH2AX foci analysis (100 cells per condition analyzed) of DNA damage in the MT, SAMT, YH and SAYH cell lines in untreated controls and 30 min, 1 h, 3 h, 6 h, and 24 h after irradiation by a single dose of 0,5 Gy. The SA mutation has only a slight impact on basal levels and the amount of DNA damage received upon irradiation (p < 0.05: MT vs. SAMT 1 h (means 3.39 vs. 2.69); p < 0.01: MT. vs. SAMT 3 h (5.29 vs. 4.31), 6 h (6.29 vs. 4.80); p < 0.001: YH/SAYH control (1.84 vs. 2.23)) and does not prevent return to basal levels. G Flow cytometry analysis of apoptosis induction in the MT, SAMT, YH and SAYH cell lines 4 days after irradiation at the indicated doses. Samples were analyzed for Annexin V positivity (early apoptosis) and propidium iodide (PI, necrotic cells) positivity. Double positive cells were counted as late apoptotic and negative cells as live cells. Apoptosis induction was similar for both pairs of cell lines. Statistical tests: 2-way anova (A, B), student’s t-test (C, D). Error bars represent the standard deviation (C, D, F) or SEM (A, B, E, G).
