ABSTRACT
Objective:To explore the mechanisms of regulation of miR-575 on the proliferation and invasion properties of non-small cell lung cancer cell (NSCLC).Methods:Real-time PCR was selected to detect the expression of miR-575 and BLID in differ ent NSCLC cell lines.CCK-8 assay was processed to measure the alternations of A549 cell proliferation at different time points after transfection of miR-575 mimic and miR-575 inhibitor.The invasion ability of A549 cells was evaluated by transwell.The targeting of BLID by miR-575 was predicted by Targetcan software and verified by dual-Luciferase assay.BLID protein expression level was detected by western blot.Results:miR-575 highly expressed in NSCLC cell lines,including A549,SPC-A1,H1299,H1650 (P＜0.001),miR-575 mimic could efficiently elevated the expression ofmiR-575 in A549 cells (P＜0.001),and strengthened the proliferation and invasion ability of NSCLC cells (P＜0.05),while,transfection of miR-575 inhibitor could down-regulate the expression ofmiR-575,and also inhibit the proliferation and invasion ability of NSCLC cells (P＜0.01).Targetscan software predicted that BLID might be the target gene of miR-575,and dual-luciferase assay revealed that miR-575 could obviously decrease the luciferase reaction of wild type BLID 3'UTR (P＜0.01),besides,miR-575 could down-regulate the protein expression ofBLID (P＜0.01).Real-time PCR results showed that NSCLC cell lines had lower level of BLID mRNA expression compared with 16HBE control cells (P＜0.001),and restore of BLID could markedly inhibited cell proliferation and invasion ability (P＜0.05),which could be reversed by miR-575 co-tranfection (P＜0.01).Conclusion:In NSCLC cells,the expression ofmiR-575 could promote cell proliferation and invasion ability by directly regulating downstream target tumor-suppressor gene BLID expression.