MicroRNA-520e inhibited the migration and invasion of lung cancer A549 cells by regulating Zinc finger protein 367

Abstract

Objective To investigate the underlying molecular mechanisms of microRNA-520e (miR-520e) in the migration and invasion of lung cancer cell line A549. Methods The reverse transcription-polymerase chain reaction (RT-PCR) was adopted to detect the expression differences of miR-520e in lung cancer cell line A549 and normal lung epithelial cell line BEAS-2B. Transfected miR-520e mimics to obtain miR-520e overexpressing cell lines. Using migration assay and Transwell assay to detect the effect of miR-520e on the migration and invasion of A549 cells. Bioinformatics was employed to predict the miR-520e-targeted Zinc finger protein 367 (ZNF367) gene. Dual luciferase assay was adopted to analyze the mechanism of miR-520e regulating ZNF367. Western blotting was used to detect the changes of ZNF367 in lung cancer cells. The effect of ZNF367 on the migration and invasion of A549 cells was studied by small interfering RNA (siRNA). Results The expression of miR-520e was 0.342 ± 0.214 in A549 cells compared with that of BEAS-2B cells (1.000 ± 0.135, P=0.000). After transfection with miR-520e mimic, compared with untransfected group [ normal control (NC) group: 1.000 ± 0.273] the expression of miR-520e in mimic group was 2.617±0.124 (P=0.000). After 24 hours of incubation, compared with NC group [(100.000 ± 12.347)%], the cell migration rate in mimic group was [(43.727 ± 16.746)%] and in scramble group was [(91.722 ± 7.631)%], overexpression of miR-520e inhibits lung cancer cell migration (P=0.000). Invasion experiments show that, the number of invasive cells in the mimic group [(36.458±21.301)%]was lower compared with the miR-520e scramble group [(93.783±9.125)%] and the NC group [(100.000±15.114)%, P=0.000]. Luciferase reporter gene results showed that transfection of miR-520e mimics inhibited luciferase activity by 0.374±0.241 (P=0.000). The expression of ZNF367 was down-regulated by miR-520e mimics (0.426 ± 0.153, P=0.000; 0.368±0.127, P=0.000) by RT-PCR and Western blotting. Further experiments showed that miR-520e targets ZNF367 gene to regulate the migration and invasion of lung cancer cells. Conclusion miR-520e inhibits the migration and invasion of lung cancer A549 cells by regulating ZNF367 Key words: MicroRNA-520e; Zinc finger protein 367; Lung cancer; Migration; Invasion