Fig. 5
Metformin inhibits the EGFR/AKT/AMPK/mTOR axis in SCLC cells. (A) The protein levels of AMPK, p-AMPK, mTOR, p-mTOR, AKT, p-AKT, EGFR, and p-EGFR were measured in H446, H446/DDP, H526, and H526/DDP cells treated with different concentrations of metformin for 48 h via western blotting. (B) The binding mode of metformin docked to EGFR. (C) ATP content of SCLC cells after treatment with metformin (0, 5, or 10 mM) for 48 h. Significant difference compared with the untreated control: *p < 0.05; **p < 0.01; ***p < 0.001. n = 3. (D) The protein levels of EGFR, p-EGFR, AKT, p-AKT, AMPK, and p-AMPK were measured via western blotting in H446 and H446/DDP cells treated with metformin (10 mM), EGF (50 µg/ml), or metformin + EGF for 48 h. (E) The protein levels of AKT, p-AKT, mTOR, p-mTOR, AMPK, and p-AMPK were measured via western blotting in H446 and H446/DDP cells treated with metformin (10 mM), SC79 (4 µg/ml), or metformin + SC79 for 48 h. (F) The protein levels of AMPK, p-AMPK, mTOR, p-mTOR, AKT, and p-AKT were measured in H446 and H446/DDP cells treated with metformin (10 mM), compound C (2 µM), or metformin + Compound C for 48 h via western blotting.
