COPB2 promotes metastasis and inhibits apoptosis of lung adenocarcinoma cells through functioning as a target of miR-216a-3p

BACKGROUND: Lung adenocarcinoma is a non-small cell lung cancer with a high mortality. There is little published data on the role of coatomer protein complex subunit β (COPB2) in lung adenocarcinoma. The current study aimed to explore the effects of COPB2 on lung adenocarcinoma cells. METHODS: The differential expression of COPB2 in normal cells and lung adenocarcinoma cells was detected by quantitative real time-polymerase chain reaction (qRT-PCR) and Western blotting. Then, cell viability assay, flow cytometry and Transwell experiments were performed to study the effects of COPB2 on cell growth, apoptosis, migration and invasion. MiRNA targeting COPB2 was predicted by TargetScan and validated by luciferase assay, qRT-PCR and Western blotting. The effects of miRNA inhibitor on siCOPB2 were analyzed by rescue experiments. Finally, apoptosis and metastatic marker proteins were detected by Western blotting. RESULTS: COPB2 was high-expressed in lung adenocarcinoma cells. Silencing COPB2 inhibited cell viability and cell metastasis, and significantly increased apoptosis. MiR-216a-3p was predicted to be able to target COBP2. Rescue experiment showed that miR-216a-3p inhibitor promoted cell viability, migration and invasion, and inhibited apoptosis of lung adenocarcinoma cells, partly reversed the effects of siCOPB2. Moreover, Western blotting showed that siCOPB2 up-regulated expressions of cleaved Caspase-3, Caspase-3, BCL2 associated X (Bax), and E-Cadherin, and down-regulated expressions of BCL2 apoptosis regulator (Bcl-2), N-Cadherin, and Vimentin, and the above effects were also partly reversed by miR-216a-3p inhibitor. CONCLUSIONS: High-expressed COPB2 promotes metastasis and inhibits apoptosis of lung adenocarcinoma cells through functioning as a target of miR-216a-3p.