circ_0000592/miR-515-5p轴调控乳腺癌细胞增殖、迁移和侵袭

Regulation of circ_0000592/miR-515-5p axis in the proliferation,migration and invasion of breast cancer cells

目的:探讨circ_0000592/miR-515-5p轴对乳腺癌细胞增殖、迁移和侵袭的影响。方法:收集57例乳腺癌病人的癌组织和癌旁组织,qRT-PCR法检测组织中circ_0000592和miR-515-5p表达;体外培养人乳腺上皮细胞HMEpiC和乳腺癌MCF-7细胞,qRT-PCR法检测细胞中circ_0000592和miR-515-5p表达。双荧光素酶报告基因实验验证circ_0000592和miR-515-5p的调控关系。转染circ_0000592小干扰RNA、或共转染circ_0000592小干扰RNA与miR-515-5p抑制剂至MCF-7细胞,CCK-8实验、克隆形成实验、Transwell分别检测细胞存活率、克隆数、迁移数和侵袭数,蛋白质印迹法检测细胞中E-cadherin和N-cadherin蛋白表达。结果:乳腺癌组织中circ_0000592表达升高(P<0.05),miR-515-5p表达降低(P<0.05)。乳腺癌MCF-7细胞中circ_0000592表达较HMEpiC细胞升高(P<0.05),miR-515-5p表达较HMEpiC细胞降低(P<0.05)。circ_0000592在MCF-7细胞中靶向结合并负调控miR-515-5p。下调circ_0000592后,MCF-7细胞存活率、克隆数、迁移数、侵袭数及细胞中N-cadherin蛋白表达均降低(P<0.01),E-cadherin蛋白表达升高(P<0.01)。下调miR-515-5p部分减弱下调circ_0000592对MCF-7细胞增殖、迁移和侵袭的作用。结论:circ_0000592在乳腺癌组织及细胞中表达升高,其通过靶向负调控miR-515-5p促进乳腺癌细胞增殖、迁移和侵袭。

Objective:To investigate the effect of circ_0000592/miR-515-5p axis on the proliferation,migration and invasion of breast cancer cells.Methods:The cancer tissues and adjacent tissues of 57 breast cancer patients were collected,and the expressions of circ_0000592 and miR-515-5p in the tissues were detected by qRT-PCR.Human breast epithelial cells HMEpiC and breast cancer MCF-7 cells were cultured in vitro.qRT-PCR method was used to detect the expression of circ_0000592 and miR-515-5p in the cells.The dual luciferase reporter gene experiment verified the regulatory relationship between circ_0000592 and miR-515-5p.MCF-7 cells were transfected with circ_0000592 small interfering RNA or miR-515-5p inhibitor,and then CCK-8 assay,clone formation test and Transwell assay were used to detect the cell viability,clone number,migration number and invasion number.The protein expression of E-cadherin and N-cadherin in cells were detected by Western blotting.Results:In breast cancer tissues,the expression of circ_0000592 was increased(P<0.05),and the expression of miR-515-5p was decreased(P<0.05).The expression of circ_0000592 in breast cancer MCF-7 cells was higher than that in HMEpiC cells(P<0.05),but the expression of miR-515-5p was lower than that in HMEpiC cells(P<0.05).Circ_0000592 could negatively regulate miR-515-5p in MCF-7 cells.After down-regulating circ_0000592,the survival rate,clone number,migration number,invasion number of MCF-7 cells and the expression of N-cadherin protein in the cells were all decreased(P<0.01),but the expression of E-cadherin protein was increased(P<0.01).Down-regulation of miR-515-5p partially restored the effectd of down-regulation of circ_0000592 on proliferation,migration and invasion of MCF-7 cells.Conclusions:The expression of circ_0000592 is elevated in breast cancer tissues and cell lines,which promotes breast cancer cell proliferation,migration and invasion through the negative regulation of miR-515-5p.