Medical Department, Queen Mary School, Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Department of Oncology, The Second Affiliated Hospital of Nanchang University, No.1 Minde Road, Dondhu District, Nanchang, 330006, Jiangxi, People's Republic of China.
Mamm Genome. 2022 Sep;33(3):543-554. doi: 10.1007/s00335-022-09950-3. Epub 2022 Apr 8.
A variety of circular RNAs (circRNAs) have tumor-regulatory roles in breast cancer (BC). Circ_0000442 was reported to inhibit the progression of BC, and this study was designed to explore the novel functional mechanism of circ_0000442 in BC. The expression analysis for circ_0000442, microRNA-1229-3p (miR-1229-3p) and zinc finger and BTB domain containing 1 (ZBTB1) was performed using the quantitative real-time polymerase chain reaction (qRT-PCR). Dual-luciferase reporter assay was used to affirm the target interaction. Cell proliferation was examined using Edu assay and colony formation assay. Cell migration and invasion were assessed by transwell assay. Flow cytometry was applied for the detection of cell apoptosis. Glycolysis was analyzed using the detection kits to measure the glucose consumption and lactate production. The protein expression levels were determined by western blot. The role of circ_0000442 in BC in vivo was explored using tumor xenograft assay. Circ_0000442 expression was downregulated and miR-1229-3p expression was upregulated in BC tissues and cells. Circ_0000442 directly interacted with miR-1229-3p. Circ_0000442 repressed proliferation, migration, invasion and glycolysis but promoted apoptosis in BC cells. The anti-tumor role of circ_0000442 was attributed to the sponge effect on miR-1229-3p. ZBTB1 was a downstream target for miR-1229-3p. Downregulation of miR-1229-3p blocked the malignant behaviors in BC cells by elevating the expression of ZBTB1. Circ_0000442 regulated the ZBTB1 level by targeting miR-1229-3p, and it inhibited tumor growth of BC in vivo by mediating the miR-1229-3p/ZBTB1 axis. All evidence unraveled that circ_0000442 impeded the progression of BC by sponging miR-1229-3p to evoke the ZBTB1 expression upregulation.
多种环状 RNA（circRNAs）在乳腺癌（BC）中具有肿瘤调节作用。circ_0000442 被报道能抑制 BC 的进展，本研究旨在探讨 circ_0000442 在 BC 中的新的功能机制。采用实时定量聚合酶链反应（qRT-PCR）对 circ_0000442、microRNA-1229-3p（miR-1229-3p）和锌指和 BTB 结构域包含 1（ZBTB1）的表达进行分析。双荧光素酶报告基因检测用于确认靶基因相互作用。通过 EdU 检测和集落形成实验检测细胞增殖。通过 Transwell 实验评估细胞迁移和侵袭。通过流式细胞术检测细胞凋亡。通过检测试剂盒分析糖酵解，以测量葡萄糖消耗和乳酸生成。通过 Western blot 测定蛋白表达水平。通过肿瘤异种移植实验探讨 circ_0000442 在体内对 BC 的作用。BC 组织和细胞中 circ_0000442 表达下调，miR-1229-3p 表达上调。circ_0000442 直接与 miR-1229-3p 相互作用。circ_0000442 抑制 BC 细胞的增殖、迁移、侵袭和糖酵解，但促进细胞凋亡。circ_0000442 通过海绵作用抑制 miR-1229-3p 发挥抗肿瘤作用。ZBTB1 是 miR-1229-3p 的下游靶基因。下调 miR-1229-3p 通过上调 ZBTB1 表达阻断 BC 细胞的恶性行为。circ_0000442 通过靶向 miR-1229-3p 调节 ZBTB1 水平，通过介导 miR-1229-3p/ZBTB1 轴抑制体内 BC 肿瘤生长。所有证据表明，circ_0000442 通过海绵吸附 miR-1229-3p 抑制肿瘤生长，从而上调 ZBTB1 的表达，阻碍 BC 的进展。
