Combination of CP@NP‐cRGD and AZD9291 enhances the antitumor effect in vitro. A,B) Cell viability of H1975/AR and HCC 827/AR cells with various treatments for 72 h by CCK8 assay. C) Apoptosis of H1975/AR cells in vitro determined by flow cytometric analysis with Annexin‐V‐FITC and PI double‐staining after incubated with different drugs for 48 h. D) The percentage of apoptotic cells included early apoptotic cells and late apoptotic cells. E,F) Flow cytometric analysis evaluated cell cycle distribution. Representative histograms shown in (E) and quantitative histograms shown in (F). The percentage of cells in each cell cycle phase in different groups was compared with AZD9291 alone group. G) Images showing the effect of different drugs of H1975/AR detected with dual staining of Hoechst 33324/PI. Blue color represented being stained with Hoechst, apoptotic cells appeared strong fluorescent signals, and healthy cells showed weakly stained. Red color represented PI staining indicating necrotic cells. Scale bar: 50 µm. H) Western blotting images showing the expression level of apoptosis‐associated and ERK proteins. All data were from three repeats, *p < 0.05, **p < 0.01, ***p < 0.001. A: AZD9291, AZD: AZD9291, PN: PD@NP‐cRGD, CN: CQ@NP‐cRGD, FCP: free CQ and PD173074.