Expression Of MiRNA-135b And Effect On Proliferation、Invasion And Migration Of Triple-negative Breast Cancer By Targeted APC

【Objective】 To explore the expression of mi RNA-135 b in normal breast cell line and breast cancer cell lines and discuss its function on the proliferation 、 invasion and migration in triple-negative breast cancer cell lines by targeting APC.【Methods 】 Quantitative real-time(RT)-PCR was used to detect the expression of mi RNA-135 b in several breast cancer cell lines and normal breast cell line :Hs578Bst、 MCF7、HCC1937、MDA-MB-231、MDA-MB-453、MDA-MB-468 、BT-549 and Hs578 T.Then choosing the three-negative breast cancer cell line MDA-MB-231 and MDA-MB-468 which express mi RNA-135 b higher to go on next study.Dividing subject cells to three groups: normal growth group,negative control group(transfected with negative counter-part)and the experimental group(transfected with mi RNA-135 b inhibitors).The proliferation change was detected by Cell Counting Kit-8(CCK-8)method and the invasion and migration were detected by Transwell assay;RT-PCR and Western-blot were used to explore the expression change of APC.【Results】 The levels of mi RNA-135 b were higher in triple-negative breast cancer cell lines :MDA-MB-231 、 MDA-MB-453 、 BT-549 and MDA-MB-468 than other types,especially MDA-MB-231(P=0.001),MDA-MB-468(P=0.036).CCK-8 results showed that after transfecting for 5 days the proliferation rate of normal growth group was 100%±0%,negative control group and and experimental group were MDA-MB-231(97.12%±2.26%,77.42%±2.20%,P=0.00)MDA-MB-468(96.8%±1.04%,84.38%±3.39%,P=0.01)compared with the control group,the difference was statistically significant.The invasion and migration ability were obviously decreased after transfected mi RNA-135 b inhibitors MDA-MB-231(P=0.002,P=0.00),MDA-MB-468(P=0.01,P=0.00).The expression of APCm RNA and APC protein,compared with the control group,MDA-MB-231(P=0.013,P=0.021),MDA-MB-468(P=0.017,P=0.014)the difference was statistically significant.【Conclusion】The expression of mi RNA-135 b were higher in Triple-negative breast cancer cell lines than other types.Mi RNA-135 b can promote Triple-negative breast cancer cells progression on proliferation,invasion and migration,and APC was one of the target genes of mi RNA-135 b by participating in the process of regulation.