Fig. 6

The combination of BEZ235 and BIBW2992 synergistically induces apoptosis in H1975 cells. a H1975 cells were treated with the indicated concentrations of BIBW2992 and BEZ235, either alone or together, for 72 h. Viability was analyzed using the WST-1 assay. b Combined treatment with BIBW2992 and BEZ235 as in Fig. S7a exerts synergistic effects. The combination index was calculated as described in Materials and Methods. c BEZ235 promotes BIBW2992-induced apoptosis. H1975 cells were treated with cisplatin and BEZ235 at the indicated concentrations for 48 h. Cell lysates were analyzed by Western blotting using the indicated antibodies. The related expression levels of protein, quantified by ImageJ as described in Materials and Methods, were shown below their corresponding blots. d The combination of BEZ235 and BIBW2992 exerts dramatic antitumor effects in NSCLC xenograft mice in vivo. BEZ235 (25 mg/kg) and BIBW2992 (5 mg/kg) were orally administered daily in mice bearing subcutaneous H1975 cell xenograft tumors. Volumes of tumors from vehicle control (●), BEZ235 (□), BIBW2992 (△) and BEZ235 + BIBW2992 (▼) groups (n = 5/group) were measured twice a week. Data are presented as means ± SEM (*, P < 0.05; **, P < 0.01; ***, P < 0.001; Student’s t-test)