FIGURE 6.

NOTCH inhibition decreases the 53BP1 foci in irradiated samples. A, Western blotting for ATM, pATM, pATR, pCHK1, pCHK2, and TP63 24 and 72 hours after RT in PBECs treated with and without GSI from day 19 to day 21, 48 hours prior to irradiation. Lamin A was used as loading control. B, 53BP1‐TP63 costaining in 0, 2, and 4 Gy samples treated with and without GSI, 2 days prior to irradiation. C, Quantification of 53BP1 staining in TP63+ cells, 24 hours and 3 days after RT in presence or absence of NOTCH inhibition at day 19 to 21, 48 hours prior RT (2‐4 Gy). N = 3 biological repeats per donor. Statistics for one‐way ANOVA: *P < .05; **P < .001. All scale bars are 1 μm. Ac‐TUB, Acetylated Tubulin; ALI, air‐liquid interface; ANOVA, analysis of variance; GSI, γ‐secretase inhibitor; PBECs, primary human bronchial epithelial cells