Changes in tumor tissue microenvironment before and after acquiring EGFR‐TKI resistance in lung carcinoma cells. A, Results of cytokine array (n = 1). Compared with the control, interleukin (IL)‐6 and IL‐8 protein expression was decreased in the miR‐1 transfected PC9 cells for 24 h. B, mRNA expression levels of cytokines (n = 3). C‐C Motif Chemokine Ligand 5 (CCL5) and C‐X‐C Motif Chemokine Ligand 10 (CXCL10) were significantly inhibited by miR‐1 transfection for 24 h in three cell lines (p < 0.05, see text for details). IL‐6, IL‐8, tumor necrosis factor (TNF)‐α were significantly inhibited in two cell lines other than PC9/ER (p < 0.05, see text for details). C, Transfection time was extended to 48 and 72 h in PC9/ER cell lines. IL‐6, IL‐8, TNF‐α were significantly inhibited (p < 0.05, see text for details) (n = 3). D, Representative findings of migrated monocytes (arrows) (bar: 100 µm). E, Monocyte migration was significantly inhibited by miR‐1 transfection (p = 0.0018) (n = 3)