FIGURE 5.

NOTCH inhibition increases the percentage of living cells and reduces Caspase 3, TP53, P21^CIP levels. A, PBECs were grown for 28 days in ALI and treated with dimethyl sulfoxide (DMSO) and GSI, from day 19 to 21, for 48 hours. Cells were irradiated with 2 and 4 Gy at 21 days. The percentage of living cells was measured after 3 and 7 days. B, Caspase 3 Western blot 1, 24, and 72 hours after RT. C, TP53 and P21^CIP blot 72 hours post‐RT. D, 50 000 cells at the 21st day after airlift were harvested and seeded for three passages and the number of living cells was measured. N = 3 biological repeats per donor. Statistics for one‐way ANOVA: *P < .05; **P < .001; ***P < .0001. Ac‐TUB, Acetylated Tubulin; ALI, air‐liquid interface; ANOVA, analysis of variance; GSI, γ‐secretase inhibitor; PBECs, primary human bronchial epithelial cells