Abstract：
Breast cancer (BC) is one of the most common malignant tumors in women. CircRNA/miRNA/mRNA regulatory axes have been shown to be involved in the pathogenesis of BC. Here, we sought to analyze the functional mechanism of circ_0104345 in BC. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the levels of circ_0104345, miR-876-3p and zinc finger and BTB domain containing 20 (ZBTB20) mRNA. Cell Counting Kit-8 (CCK8) and 5-ethynyl-2\'-deoxyuridine (EdU) assays were used to test cell viability and proliferation, respectively. Cell migration was tested by wound healing assay, and cell invasion was examined by transwell assay. Tube formation ability was tested by angiogenesis assay. Flow cytometry was applied for cell apoptosis. Western blot assay was utilized to measure the protein expression. The relationship between miR-876-3p and circ_0104345 or ZBTB20 was identified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Xenografts in mice were conducted to analyze the effect of sh-circ_0104345 on tumor growth in vivo. Circ_0104345 and ZBTB20 were upregulated and miR-876-3p expression was decreased in BC. Circ_0104345 knockdown inhibited cell proliferation, migration, invasion, and enhanced cell apoptosis. MiR-876-3p was targeted by circ_0104345. MiR-876-3p depletion reversed the effects of circ_0104345 downregulation on the progression of BC cells. ZBTB20 was regulated by circ_0104345 through miR-876-3p. The effects of miR-876-3p on BC cell behaviors were restored by ZBTB20 increase. The results of in vivo experiments indicated that silencing of circ_0104345 blocked the growth of xenograft tumors. In this study, we demonstrated, for the first time, the crucial regulation of the new circ_0104345/miR-876-3p/ZBTB20 axis in the biological phenotypes of BC cells.
摘要：
乳腺癌是女性最常见的恶性肿瘤之一。已显示CircRNA/miRNA/mRNA调节轴参与BC的发病机理。这里,我们试图分析circ_0104345在BC中的作用机制。进行定量实时聚合酶链反应(qRT-PCR)以检测circ_0104345、miR-876-3p和锌指以及含有20(ZBTB20)mRNA的BTB结构域的水平。细胞计数试剂盒-8（CCK8）和5-乙炔基-2'-脱氧尿苷（EdU）测定用于测试细胞活力和增殖，分别。通过伤口愈合试验测试细胞迁移，并通过transwell测定法检查细胞侵袭。通过血管生成测定法测试管形成能力。流式细胞术用于细胞凋亡。使用蛋白质印迹测定法来测量蛋白质表达。miR-876-3p与circ_0104345或ZBTB20之间的关系通过双荧光素酶报告基因测定和RNA免疫沉淀(RIP)测定来鉴定。在小鼠中进行异种移植物以分析sh-circ_0104345对体内肿瘤生长的影响。BC中Circ_0104345和ZBTB20上调，miR-876-3p表达降低。Circ_0104345敲低抑制细胞增殖，迁移,入侵,增强细胞凋亡。miR-876-3p被circ_0104345靶向。MiR-876-3p耗尽逆转了circ_0104345下调对BC细胞进展的影响。ZBTB20由circ_0104345通过miR-876-3p调节。miR-876-3p对BC细胞行为的影响可通过增加ZBTB20恢复。体内实验的结果表明circ_0104345的沉默阻断了异种移植肿瘤的生长。在这项研究中,我们展示了，第一次,新circ_0104345/miR-876-3p/ZBTB20轴在BC细胞生物学表型中的关键调控。
