Fig. 2

Contribution of APCDD1L-AS1 to the icotinib resistance of LUAD cells. a The localization and structure of APCDD1L-AS1 on the chromosome in the LNCipedia database. b The coding potentials of lncRNAs (MALAT1, TUG1, APCDD1L-AS1) and mRNAs (GAPDH, ACTB, SDHA) were calculated using CPAT database. c The online software lncLocator was used to predict the subcellular localization of APCDD1L-AS1. d Relative expression of APCDD1L-AS1 in cytoplasm or nucleus of the icotinib-resistant cells (PC9/IcoRH, HCC827/IcoRH) was determined by qRT-PCR. e The localization of APCDD1-AS1 in the PC9/IcoRH cells was detected by RNA-FISH. Blue, DAPI-stained nuclei; Red, Cy3-labeled positive hybridization signals (scale bar, 100 μm). U6 and 18S were used as positive controls. f The effect of APCDD1L-AS1 KD on the IC50 value of icotinib was evaluated in icotinib-resistant cells (PC9/IcoRH, HCC827/IcoRH) by MTT assay. g The level of EGFR and p-EGFR in APCDD1L-AS1-KD or -OE icotinib-resistant cells (PC9/IcoRH, HCC827/IcoRH) was determined by western blot. h Kaplan-Meier analyses of the correlations between APCDD1L-AS1 expression (classified into high and low expression groups according to the median of APCDD1L-AS1 expression) and OS in 672 lung adenocarcinoma patients using Kaplan-Meier Plotter online database. Log rank test was used to calculate P values. i-j The apoptosis of APCDD1L-AS1-KD icotinib-resistant cells (PC9/IcoRL, PC9/IcoRH) induced by icotinib (10 μM) was analyzed using flow cytometry (i), and apoptosis-related protein PARP in PC9/IcoRL and PC9/IcoRH cells was detected by western blot (j). GAPDH was used as the internal control. The mean ± SD of triplicate experiments were plotted, *P < 0.05, **P < 0.01, ***P < 0.001