Fig. 5

a Efficacy of copanlisib (□), lapatinib (○) and a combination of lapatinib and copanlisib (Δ) in a panel of gastric cancer cell lines. Error bars are representative of standard deviations across triplicate experiments. The ratio of drugs is indicated on each graph. b Efficacy of refametinib (◊), lapatinib (○) and a combination of lapatinib and refametinib (Δ) in a panel of gastric cancer cell lines. Error bars are representative of standard deviations across triplicate experiments. The ratio of drugs is indicated on each graph. c The efficacy of combining trastuzumab (T) at 10 µg/ml and copanlisib (C) at varying concentrations in a panel of gastric cancer cell lines. *indicates a p-value < 0.05 as calculated by Kruskal–Wallis non-parametric test. d The efficacy of combining trastuzumab (T) at 10 µg/ml and refametinib (R) at varying concentrations in a panel of gastric cancer cell lines. Standard deviations are representative of independent triplicate experiments