Effect of miR-145 on Migration and Invasion of Ovarian Cancer Cells

Abstract

Objective To evaluate the effect of miR-145 on migration and invasion of ovarian cancer cells.Methods The effect of miR-145 overexpression on the expression levels of miR-145 and zeb-2 were detected with qRT-PCR and Western blotting.The changes of in vitro migration and invasion were examined using Transwell assay.Target genes of miR-145 were predicted by bioinformatics software.Dual-luciferase reporter assay were used to verify zeb-2 as a direct target of miR-145.zeb-2 siRNA was transiently transfected in SKOV3 and 3AO cells,Transwell was used to examine in vitro migration and invasion abilities.Results The migration and proliferation of SKOV3(t=10.752,P=0.000;t=5.617,P=0.005)and 3AO cells(t=10.111,P=0.001;t=21.746,P=0.000)decreased significantly after overexpression of miR-145.The results of dual-luciferase reporter assay showed that the relative luciferase activity of co-transfected miR-145 mimic and WT 3'UTR expression vectors was significantly lower than that of co-transfected mimic control and WT 3'UTR expression vectors(SKOV3:t=4.572,P=0.010;3AO:t=3.528,P=0.024).There was no significant difference in relative luciferase activity between co-transfected miR-145 mimic/MUT 3'UTR expression vector cells and co-transfected mimic control/MUT 3'UTR expression vector cells(SKOV3:t=0.227,P=0.831;3AO:t=0.040,P=0.970).Real-time quantitative PCR showed that the zeb-2 expressions in SKOV3(t=1.490,P=0.211)and 3AO cells(t=0.114,P=0.914)were not significantly different from negative control after 48 h of miR-145 overexpression.Western blot analysis showed that the expression of zeb-2 protein in SKOV3(t=3.769,P=0.020)and 3AO cells(t=4.452,P=0.011)decreased significantly compared with negative control after 72 h of miR-145 overexpression.Seventy-two hours after transfection of zeb-2 siRNA,Western blotting showed that the expression of zeb-2 protein in SKOV3(t=4.660,P=0.010)and 3AO cells(t=4.594,P=0.010)was significantly down-regulated.Transwell assay showed that the migration and invasion abilities of SKOV3(t=18.655,P=0.000;t=18.026,P=0.000)and 3AO cells(t=5.500,P=0.005;t=8.780,P=0.001)were significantly decreased.Conclusion miR-145 may inhibit the migration and invasion of ovarian cancer cells by targeting zeb-2.