Fig. 4

EGFR-TKIs and PHA-767491 synergise to induce G2/M cell cycle arrest and apoptosis. a Inhibition of cell cycle components by co-treatment with EGFR-TKIs (lapatinib, erlotinib or gefitinib) and PHA-767491. Hs578T and SKBR7 cells were treated with EGFR-TKI alone (3.16 μM) or combined with PHA-767491 (1 μM or 3.16 μM) for 48 h as indicated. b Cell cycle distribution of Hs578T and SKBR7 cells after 48-h treatment with EGFR-TKIs (3.16 μM) alone or combined with PHA-767491 (1 μM or 3.16 μM), as indicated. Data shown as mean of two independent experiments ± standard deviation. c Induction of apoptosis by EGFR-TKI and PHA-767491 co-treatment. Hs578T and BT549 cells were treated with lapatinib (3.16 μM), PHA-767491 (3.16 μM), alone or combined, as indicated, for 24 h, 48 h or 72 h, respectively, and then stained with Annexin-V and Hoechst, followed by imaging and image quantification. Data shown as mean ± standard deviation of two independent experiments. Relative cell death was quantified by normalising the intensity of Annexin-V signal to that of DMSO control. One-way ANOVA ****P ≤ 0.0001, ***P ≤ 0.001, **P ≤ 0.01, *P ≤ 0.05