Department of the Second Ward of Breast Surgery, The Third Clinical Medical College of Xinjiang Medical University, Xinjiang, China.
Department of the Second Ward of Pulmonary Medicine, The Third Clinical Medical College of Xinjiang Medical University, Xinjiang, China.
Breast Cancer. 2020 Jul;27(4):765-775. doi: 10.1007/s12282-020-01075-2. Epub 2020 Mar 6.
To investigate the mechanism of miR-485-5p inhibiting breast cancer cells by targeting MUC1.
Differentially expressed genes (DEGs) in breast cancer tissues were analyzed using breast cancer tissue microarrays (TMA) in the GEO database. Differential expression of MUC1 in breast cancer tissue samples was detected by TCGA database. qRT-PCR was used to detect the expression of MUC1 and miR-485-5p in human normal breast epithelial cell lines and human breast cancer cell lines. Bioinformatics was applied to analyze targeted binding site of miR-485-5p and MUC1 and their targeted relationship was identified by dual luciferase assay. The proliferation ability of breast cancer cells was detected by CCK-8 assay. Cell apoptosis was detected by flow cytometry. The ability of cell migration was measured by scratch healing test. Transwell assay was used to detect the invasion ability of cells. The protein expression levels of MUC1 and EMT-related molecules (E-cadherin, N-cadherin and Vimentin) were detected by Western blot.
MUC1 was highly expressed in breast cancer tissue samples and breast cancer cell lines, while miR-485-5p was lowly expressed. Overexpression of miR-485-5p inhibits cell viability and invasion and migration of breast cancer cell line MCF-7 and promotes apoptosis. The same results were obtained by silencing the expression of MUC1. MiR-485-5p targets to bind to the 3'-UTR region of MUC1 and negatively regulates the expression of MUC1. Overexpressing MUC1 while overexpressing miR-485-5p reversed the inhibitory effect of miR-485-5p on breast cancer and inhibited EMT.
MiR-485-5p can down-regulate the expression of MUC1, thus inhibit the proliferation, invasion and migration of breast cancer cells and promote cell apoptosis.
通过靶向 MUC1 研究 miR-485-5p 抑制乳腺癌细胞的机制。
利用 GEO 数据库中的乳腺癌组织微阵列（TMA）分析乳腺癌组织中的差异表达基因（DEGs）。通过 TCGA 数据库检测乳腺癌组织样本中 MUC1 的差异表达。qRT-PCR 检测人正常乳腺上皮细胞系和人乳腺癌细胞系中 MUC1 和 miR-485-5p 的表达。应用生物信息学分析 miR-485-5p 与 MUC1 的靶向结合位点，并通过双荧光素酶报告实验鉴定其靶向关系。CCK-8 检测乳腺癌细胞的增殖能力。流式细胞术检测细胞凋亡。划痕愈合实验检测细胞迁移能力。Transwell 实验检测细胞侵袭能力。Western blot 检测 MUC1 及 EMT 相关分子（E-cadherin、N-cadherin 和 Vimentin）的蛋白表达水平。
MUC1 在乳腺癌组织样本和乳腺癌细胞系中高表达，而 miR-485-5p 低表达。过表达 miR-485-5p 可抑制乳腺癌细胞系 MCF-7 的细胞活力、侵袭和迁移，并促进细胞凋亡。沉默 MUC1 表达可获得相同结果。miR-485-5p 靶向结合 MUC1 的 3'-UTR 区并负调控 MUC1 的表达。过表达 MUC1 同时过表达 miR-485-5p 可逆转 miR-485-5p 对乳腺癌的抑制作用并抑制 EMT。
miR-485-5p 可下调 MUC1 的表达，从而抑制乳腺癌细胞的增殖、侵袭和迁移，并促进细胞凋亡。
