Xia Wenfei, Liu Yun, Du Yaying, Cheng Teng, Hu Xiaopeng, Li Xingrui
Department of Breast and Thyroid Surgery, Division of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, People's Republic of China.
Department of ENT, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, People's Republic of China.
Onco Targets Ther. 2020 Jan 24;13:769-782. doi: 10.2147/OTT.S217745. eCollection 2020.
BACKGROUND/AIMS: The effects of microRNA-423 on proliferation and drug resistance of breast cancer cells were explored, the downstream target genes of miR-423 and the targeted regulatory relationship between them were studied.
RT-qPCR was used to detect the expression of miR-423 in breast cancer tissues and cell lines, and the transfection efficiency of miR-423 inhibitory vector miR-423-inhibitor was constructed and verified. CCK-8 and colony formation assays were used to examine the effect of miR-423 on tumor cell proliferation. Target gene prediction and screening and luciferase reporter assay were used to verify downstream target genes of miR-432. The mRNA and protein expression of miR-423target gene ZFP36 was detected by RT-qPCR and Western blotting.
The expression of miR-423 was significantly higher than that in normal tissues. Compared to the non-malignant mammary epithelial cell line MCF-10A, the expression of miR-423 was significantly raised in MCR-7 and MCF-7/ADR cells. ZFP36 was a downstream target gene of miR-423 and negatively correlated with the expression of miR-423 in breast cancer. The knockdown of miR-423 can significantly enhance the cytotoxicity of the drug, increase the apoptotic rate of MCF-7/ADR cells. miR-423 was capable of activating the Wnt/β-catenin signaling pathway leading to chemoresistance and proliferation, whereas overexpression of ZFP36 reduced drug resistance and proliferation.
miR-423 acted as an oncogene to promote tumor cell proliferation and migration. ZFP36 was a downstream target gene of miR-423, and miR-423 inhibited the expression of ZFP36 via Wnt/β-catenin signaling pathway of breast cancer cells.
背景/目的：探讨微小RNA-423（miR-423）对乳腺癌细胞增殖和耐药性的影响，研究miR-423的下游靶基因及其靶向调控关系。
采用逆转录-定量聚合酶链反应（RT-qPCR）检测miR-423在乳腺癌组织及细胞系中的表达，构建并验证miR-423抑制载体miR-423-inhibitor的转染效率。采用细胞计数试剂盒-8（CCK-8）法和集落形成试验检测miR-423对肿瘤细胞增殖的影响。通过靶基因预测筛选及荧光素酶报告基因试验验证miR-432的下游靶基因。采用RT-qPCR和蛋白质免疫印迹法检测miR-423靶基因锌指蛋白36（ZFP36）的mRNA和蛋白表达。
miR-423在乳腺癌组织中的表达显著高于正常组织。与非恶性乳腺上皮细胞系MCF-10A相比，miR-423在MCR-7和MCF-7/ADR细胞中的表达显著升高。ZFP36是miR-423的下游靶基因，且与乳腺癌中miR-423的表达呈负相关。敲低miR-423可显著增强药物的细胞毒性，增加MCF-7/ADR细胞的凋亡率。miR-423能够激活Wnt/β-连环蛋白信号通路，导致化疗耐药和细胞增殖，而ZFP36的过表达则降低了耐药性和细胞增殖。
miR-423作为一种癌基因促进肿瘤细胞增殖和迁移。ZFP36是miR-423的下游靶基因，miR-423通过乳腺癌细胞的Wnt/β-连环蛋白信号通路抑制ZFP36的表达。
