The Effects Of MiRNA Specific For OPN On The Cisplatin Sensitivity Of Lung Adenocarcinoma Cell Line

Objective:MicroRNA targeting OPN(Osteopontin)gene was transfected transiently to Lung adenocarcinoma cell line A549 cells by the expression plasmids which were constructed in vitro.To investigate the effect of silencing OPN gene expression by using microRNA (miRNA) on A549 cells to cisplatin (DDP).Methods:1. MicroRNA expression plasmids targeting OPN gene was transfected transiently to A549 cells. The level of OPN protein in the A549 cells at 48 h after transfection was measured with ELISA.2. The cells incubated and non - incubated with 5μg/ml DDP were detected by MTT at 24, 48, 72 and 96 h after transfection.3. The cells at 24 h after transfection were cultured with different concentrations of cisplatin (DDP) for 48 h, the growth inhibition rate was evaluated by MTT.Result:1. The OPN protein level was decreased by 47.34% at 48 h after transfection(p<0.01).2. The cell proliferation started to be inhibited at 24 h after transfection(p<0.05), and was significantly inhibited at 48, 72 and 96 h after transfection. The absorbance were 1.36±0.11 , 1.54±0.13 ,1.71±0.14, respectively (p< 0.01). Treatment with 5μg/ml DDP after 24 h of transfection, the cell proliferation started to be inhibited at 24 h(p<0.05), and was significantly inhibited at 48, 72 and 96 h. The absorbance were 0.41±0.03, 0.29±0.01, 0.18±0.01, respectively (p<0.01).3. Following treatment with 2.5, 5, 10, 20μg/ml DDP for 48 h after 24 h of transfection, the cell proliferation was significantly inhibited, the growth inhibition rates were(60.87±0.07)%,(77.72±0.06)%,(85.87±0.08)%,(92.39±0.06) %, respectively (p<0.01).Conclusion:MicroRNA targeting OPN gene can effectively inhibite the cell proliferation of Lung adenocarcinoma cell line and enhances the cell chemosensitization to DDP.