MicroRNA-9 通过下调 FOXO1 促进乳腺癌细胞的增殖、迁移和侵袭。
MicroRNA-9 promotes the proliferation, migration, and invasion of breast cancer cells via down-regulating FOXO1.
机构信息
Department of Emmengey, The First Affiliated Hospital of Shantou University Medical College, Shantou, 515041, People's Republic of China.
Department of Orthopedics, The First Affiliated Hospital of Shantou University Medical College, Shantou, 515041, People's Republic of China.
出版信息
Clin Transl Oncol. 2017 Sep;19(9):1133-1140. doi: 10.1007/s12094-017-1650-1. Epub 2017 Apr 10.
PURPOSE
The objective of the study was to investigate the role of microRNA-9 (miR-9) targeting forkhead box O1 (FOXO1) in the proliferation, migration, and invasion of breast cancer cells.
METHODS
Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to determine the expressions of miR-9 and FOXO1 mRNA in breast cancer tissues, normal breast tissues, breast cancer cell lines, and normal breast epithelial cells. After the up-regulation of miR-9 expression, qRT-PCR and Western blotting were used to determine the expression of FOXO1. The luciferase reporter gene assay was used to validate the target gene. The CCK-8 assay, scratch-wound healing assay, and Transwell invasion assay were used to investigate the changes in the proliferation, migration, and invasion of breast cancer cells, respectively.
RESULTS
MicroRNA-9 expression was significantly up-regulated in breast cancer tissues and breast cancer cell lines when compared with normal breast tissues and normal breast epithelial cells (both P < 0.05). FOXO1 mRNA and protein expressions were substantially down-regulated in breast cancer tissues and breast cancer cell lines when compared with normal breast tissues and normal breast epithelial cells (both P < 0.05). There can be a negative correlation between miR-9 and FOXO1 mRNA in breast cancer. Luciferase reporter gene assay indicated that miR-9 can down-regulate FOXO1 expression at a post-transcriptional level through binding specifically to FOXO1 3'UTR. The results of CCK-8 assay, scratch-wound healing assay, and Transwell invasion assay revealed that the inhibition of miR-9 can suppress MCF7 cell proliferation, migration, and invasion. Additionally, the expression of miR-9 increased significantly whilst that of FOXO1 decreased substantially as the disease progressed (P < 0.05).
CONCLUSIONS
Our study provides evidence that miR-9 can promote the proliferation, migration, and invasion of breast cancer cells via down-regulating FOXO1.
目的
本研究旨在探讨 microRNA-9（miR-9）靶向叉头框 O1（FOXO1）在乳腺癌细胞增殖、迁移和侵袭中的作用。
方法
采用实时定量聚合酶链反应（qRT-PCR）检测乳腺癌组织、正常乳腺组织、乳腺癌细胞系和正常乳腺上皮细胞中 miR-9 和 FOXO1mRNA 的表达。上调 miR-9 表达后，采用 qRT-PCR 和 Western blot 检测 FOXO1 的表达。采用荧光素酶报告基因检测验证靶基因。CCK-8 检测、划痕愈合实验和 Transwell 侵袭实验分别用于研究乳腺癌细胞增殖、迁移和侵袭的变化。
结果
miR-9 在乳腺癌组织和细胞系中的表达明显高于正常乳腺组织和正常乳腺上皮细胞（均 P<0.05）。FOXO1mRNA 和蛋白在乳腺癌组织和细胞系中的表达明显低于正常乳腺组织和正常乳腺上皮细胞（均 P<0.05）。乳腺癌中 miR-9 和 FOXO1mRNA 之间存在负相关。荧光素酶报告基因检测表明，miR-9 可通过与 FOXO1 3'UTR 特异性结合在转录后水平下调 FOXO1 表达。CCK-8 检测、划痕愈合实验和 Transwell 侵袭实验的结果表明，抑制 miR-9 可抑制 MCF7 细胞的增殖、迁移和侵袭。此外，随着疾病的进展，miR-9 的表达显著增加，而 FOXO1 的表达显著降低（P<0.05）。
结论
本研究表明，miR-9 可通过下调 FOXO1 促进乳腺癌细胞的增殖、迁移和侵袭。
Zotero 插件