Department of Thyroid and Breast Surgery, Xianning Central Hospital, The First Affiliated Hospital of Hubei University of Science and Technology, Xianning, China.
School of Pharmacy, Hubei University of Science and Technology, Xianning, China.
Cancer Biother Radiopharm. 2021 Aug;36(6):467-476. doi: 10.1089/cbr.2019.3513. Epub 2020 May 8.
Breast cancer is one of the leading causes of cancer-associated death. This work aimed to explore the expression, function, and mechanism of circ_0000526 on the progression of breast cancer. The expressions of circ_0000526, miR-492, and suppressor of cytokine signaling 2 () in breast cancer samples were measured using quantitative real-time polymerase chain reaction. The correlation between pathological indexes of patients and the expression of circ_0000526 was also analyzed. Human breast cancer cell lines MCF-7 and MDA-MB-231 were applied to investigate the associated mechanism. Cell counting kit-8 assays were used to assess the effect of circ_0000526 on proliferation, and together with the wound healing assay, transwell assay was conducted to detect the effects of circ_0000526 on migration and invasion. Furthermore, luciferase reporter assay was used to verify the targeting relationship between miR-492 and circ_0000526. In addition, Western blot was performed to detect the regulatory effects of circ_0000526 on . Circ_0000526 expression in breast cancer samples was downregulated, which was correlated with unfavorable pathological indexes. It significantly inhibited the proliferation and metastasis of breast cancer cells, and facilitated apoptosis. The overexpression of circ_0000526 remarkably inhibited the expression of miR-492 by sponging it, and in turn promoted the expression of . Circ_0000526 served as a tumor suppressor, which could function as the sponge of miR-492, an oncogenic microRNA, in breast cancer, and enhance the expression of tumor suppressor indirectly.
乳腺癌是癌症相关死亡的主要原因之一。本研究旨在探索 circ_0000526 在乳腺癌进展中的表达、功能和作用机制。采用实时定量聚合酶链反应检测乳腺癌样本中 circ_0000526、miR-492 和细胞因子信号转导抑制因子 2() 的表达。还分析了患者病理指标与 circ_0000526 表达的相关性。应用人乳腺癌细胞系 MCF-7 和 MDA-MB-231 研究相关机制。细胞计数试剂盒-8 检测用于评估 circ_0000526 对增殖的影响，与划痕愈合实验一起进行 Transwell 实验检测 circ_0000526 对迁移和侵袭的影响。此外，通过荧光素酶报告基因实验验证 miR-492 与 circ_0000526 之间的靶向关系。另外，Western blot 检测 circ_0000526 对的调节作用。乳腺癌样本中 circ_0000526 的表达下调，与不良病理指标相关。它显著抑制乳腺癌细胞的增殖和转移，促进细胞凋亡。circ_0000526 的过表达通过海绵吸附显著抑制 miR-492 的表达，并反过来促进的表达。Circ_0000526 作为一种肿瘤抑制因子，可作为乳腺癌中致癌 microRNA miR-492 的海绵，间接增强肿瘤抑制因子的表达。
