Effects of microRNA-324 on the migration and invasion ability and ETS1 expression of non-small cell lung cancer cells

YU Faming; JIANG Dongliang; ZHAO Yun; LIU Chuanwen; YANG Guoqing

doi:10.3969/j.issn.1009-0460.2018.03.004

Abstract：Objective To explore the effect of microRNA-324 (miR-324) on the migration and invasion ability and E26 transformation specific 1 (ETS1) expression of non-small cell lung cancer (NSCLC) cells. Methods The real-time quantitative PCR (QPCR) was used to compare the level of miR-324 in normal bronchial epithelial cell 16HBE and NSCLC cell H322. MiR-324 inhibitors or mimics were transfected into H322 cells (inhibition group and overexpression group) by liposome Lipofectamine 2000, and cells only transfected with Lipofectamine 2000 were used as empty transfection group. QPCR was used to verify the miR-324 level in each group at 48 h after transfection. CCK-8 assay was used to detect the proliferative rates at 24, 48 and 72 h after transfection. The migration and invasion abilities of each group were detected by Transwell method. The expression of ETS1 was detected by Western blotting at 48 h after transfection. Results QPCR detection showed that the level of miR-324 in H322 cells was 0.172±0.023, lower than 1.106±0.274 in normal bronchial epithelial cells, and the difference was statistically significant (P＜0.05). The levels of miR-324 were 1.069±0.082, 0.287±0.034 and 7.114±0.726 in empty transfection group, inhibition group and overexpression group, respectively. Compared with empty transfection group, the level of miR-324 increased in overexpression group but decreased in inhibition group (P＜0.05 ). Compared with the empty transfection group, the proliferative rates decreased in overexpression group but increased in the inhibition group (P＜0.05 ). Transwell assay showed that for empty transfection group, inhibition group and overexpression group, numbers of cell penetrating membrane were 472.3±35.6, 692.1±50.6 and 341.7±37.5 in the migration assay and 392.1±40.5, 521.6±57.6 and 228.3±31.6 in the invasion assay. Compared with the empty transfection group, the number of penetrating membrane cells increased in the inhibition group but decreased in the overexpressed group (P＜0.05). Results of Western blotting showed that protein levels of ETS1 were 0.56±0.13, 0.87±0.23 and 0.26±0.09 in empty transfection group, inhibition group and overexpression group. Compared with the empty transfection group, expression level of ETS1 increased in inhibition group but decreased in overexpression group (P＜0.05). Conclusion The expression of miR-324 in NSCLC cells was downregulated, and it can inhibit cell proliferation, invasion and metastasis, and plays a similar role as tumor suppressor gene possibly through the targeted regulation of transcription factor ETS1.