Figure 5

Gefitinib-induced apoptosis in H-157 cells before and after irradiation. Attached cells were exposed to 6 Gy irradiation and then treated with 100 nmol/L gefitnib. After additional 48-hour incubation in medium containing the drugs, the cells were harvested. The apoptotic index (AI) was measured using flow cytometry. (A) Control groups (AI: 1.36 ± 0.74%). (B) Apoptotic values after treatment with 100 nmol/L gefitinib alone (AI:3.58 ± 0.61%).(C) Radiation- induced apoptosis induction (14.26 ± 2.97%% of total cells) in H-157 cells.(D) Radiation combined with gefitinib induced apoptosis induction (23.58 ± 3.61% of total cells). Apoptotic values were normalized by subtracting control values; the normalized apoptotic values were used for statistical analyses. Experiments were done in triplicate. Combined drug treatments were shown to enhance radiation-induced apoptosis in H-157 cells (t = 19.91, P < 0.01), but no synergistic manner when compared with drug alone without radiation (t = 2.569, P > 0.05).