miR-4715-5p通过靶向MUC1基因对乳腺癌细胞迁移和增殖的影响

Effect of miR-4715-5p on the Migration and Proliferation of Breast Cancer Cells by Targeting the MUC1 Gene

目的分析微小RNA(miRNA,miR)-4715-5p在乳腺癌组织和细胞系中的表达水平,探讨其高表达对乳腺癌细胞迁移和增殖的影响及机制。方法采用实时荧光定量PCR(qRT-PCR)法检测miR-4715-5p在乳腺癌组织和细胞系中的表达水平。在miR-4715-5p表达水平最低的乳腺癌细胞中,采用体外转染法分别转染对照模拟物(NC)和miR-4715-5p模拟物,分别命名为对照组和实验组。qRT-PCR法检测两组细胞中miR-4715-5p的表达水平。采用细胞划痕实验和细胞计数试剂盒(cell counting kit-8,CCK-8)检测高表达miR-4715-5p对乳腺癌细胞迁移和增殖的影响。采用生物信息学软件和双荧光素酶报告基因实验分别预测和验证miR-4715-5p的靶基因。采用qRT-PCR和Western blot法分别检测靶基因在mRNA和蛋白水平的表达。结果与癌旁组织比较,乳腺癌组织miR-4715-5p的表达水平显著降低(P<0.01)。与正常乳腺细胞系比较,乳腺癌细胞系miR-4715-5p的表达水平显著降低(P<0.05),MCF-7细胞中的表达水平最低(P<0.01)。与对照组比较,实验组MCF-7细胞中miR-4715-5p的表达水平显著增加(P<0.01)。高表达miR-4715-5p可显著抑制乳腺癌MCF-7细胞的迁移(P<0.01)和增殖(P<0.05)。miR-4715-5p的靶基因可能是黏蛋白1(mucins 1,MUC1),miR-4715-5p可互补结合MUC1 mRNA(P<0.01)。高表达miR-4715-5p可显著抑制MUC1基因的表达(P<0.01)。结论miR-4715-5p在乳腺癌组织和细胞系中的表达水平显著降低,高表达miR-4715-5p可通过下调MUC1基因的表达,抑制乳腺癌MCF-7细胞的迁移和增殖。

Objective To analyze the expression level of miR-4715-5p in breast cancer tissues and cell lines,and explore the effect and mechanism of miR-4715-5p on breast cancer cell migration and proliferation.Methods Real-time fluorescence quantitative PCR(qRT-PCR)method was used to detect the expression level of miR-4715-5p in breast cancer tissues and cell lines.In breast cancer cells with the lowest expression level of miR-4715-5p,the control mimic(NC)and miR-4715-5p mimic were transfected by in vitro transfection,respectively,named as control group and experimental group.qRT-PCR was used to detect the expression level of miR-4715-5p in the two groups of cells.The effects of highly expressed miR-4715-5p on the migration and proliferation of breast cancer cells were detected using cell scratch test and cell counting kit-8(CCK-8).Bioinformatics software and dual luciferase reporter gene experiments were used to predict and verify the target gene of miR-4715-5p,respectively.qRT-PCR and Western blot were used to detect the expression of target genes at the mRNA and protein levels,respectively.Results Compared with adjacent tissues,the expression level of miR-4715-5p in breast cancer tissues was significantly reduced(P<0.01).Compared with normal breast cell lines,the expression level of miR-4715-5p in breast cancer cell line was significantly reduced(P<0.05),and the expression level in MCF-7 cells was the lowest(P<0.01).Compared with the control group,the expression level of miR-4715-5p in MCF-7 cells of the experimental group was significantly increased(P<0.01).High expression of miR-4715-5p can significantly inhibit the migration(P<0.01)and proliferation(P<0.05)of breast cancer MCF-7 cells.The target gene of miR-4715-5p may be mucins 1(MUC1),and miR-4715-5p can complement MUC1 mRNA(P<0.01).High expression of miR-4715-5p can significantly inhibit the expression of MUC1 gene(P<0.01).Conclusion The expression level of miR-4715-5p in breast cancer tissues and cell lines is significantly reduced.High expression of miR-4715-5p can inhibit the migration and proliferation of breast cancer MCF-7 cells by down-regulating the expression of MUC1 gene.