Department of Surgery Oncology, Taizhou Cancer Hospital, Taizhou, China.
Department of Thyroid and Breast, Shulan (Hangzhou) Hospital Affiliated to Zhejiang Shuren University Shulan International Medical College, Hangzhou, China.
Thorac Cancer. 2023 Aug;14(22):2198-2209. doi: 10.1111/1759-7714.15007. Epub 2023 Jun 22.
The effect of circular RNAs (circRNAs) is widely studied in various human cancers, including breast cancer (BC). Herein, circUSPL1 has been recognized as a new regulator for BC progression. However, the detailed biological function and molecular mechanism of circUSPL1 in BC remain vague.
The expression level of circUSPL1, miR-1296-5p and metastasis associated 1 (MTA1) was examined by quantitative reverse transcription PCR. BC cell proliferation, migration, invasion, apoptosis and aerobic glycolysis were analyzed by colony formation assay, 5-ethynyl-2'-deoxyuridine assay, wound healing assay, transwell assay, flow cytometry and glycolysis corresponding kits, respectively. The protein level of Bcl-2, Bax, HK2, GLUT1 and MTA1 was evaluated by western blot analysis. The relationship of miR-1296-5p and circUSPL1 or MTA1 was affirmed using dual-luciferase reporter or RIP assays. A murine xenograft model was conducted to analyze the tumor growth in vivo.
CircUSPL1 and MTA1 expression level was increased, but miR-1296-5p was particularly reduced in BC tissues and cells. CircUSPL1 deficiency significantly inhibited BC cell proliferation, migration, invasion, glycolysis, and promoted cell apoptosis. In addition, circUSPL1 directly targeted miR-1296-5p, and downregulation of miR-1296-5p eliminated the inhibitory action of circUSPL1 knockdown. Additionally, overexpression of miR-1296-5p repressed cell malignant properties, while the suppressive effects were overturned by MTA1 elevation. Lastly, silencing of circUSPL1 inhibited tumor growth by sponging miR-1296-5p and regulating MTA1.
CircUSPL1 deficiency repressed BC cell malignant phenotypes through reducing MTA1 via targeting miR-1296-5p, which might provide a theoretical basis for BC treatment.
环状 RNA（circRNAs）在包括乳腺癌（BC）在内的各种人类癌症中的作用得到了广泛研究。在此，circUSPL1 已被认为是 BC 进展的新调节剂。然而，circUSPL1 在 BC 中的详细生物学功能和分子机制仍不清楚。
通过定量逆转录 PCR 检测 circUSPL1、miR-1296-5p 和转移相关蛋白 1（MTA1）的表达水平。通过集落形成试验、5-乙炔基-2'-脱氧尿苷试验、划痕愈合试验、transwell 试验、流式细胞术和糖酵解试剂盒分别分析 BC 细胞的增殖、迁移、侵袭、凋亡和有氧糖酵解。通过 Western blot 分析评估 Bcl-2、Bax、HK2、GLUT1 和 MTA1 的蛋白水平。通过双荧光素酶报告或 RIP 测定证实 miR-1296-5p 与 circUSPL1 或 MTA1 的关系。通过建立小鼠异种移植模型在体内分析肿瘤生长情况。
circUSPL1 和 MTA1 的表达水平升高，而 miR-1296-5p 在 BC 组织和细胞中表达降低。circUSPL1 缺失显著抑制 BC 细胞的增殖、迁移、侵袭、糖酵解，并促进细胞凋亡。此外，circUSPL1 可直接靶向 miR-1296-5p，下调 miR-1296-5p 消除了 circUSPL1 敲低的抑制作用。此外，过表达 miR-1296-5p 抑制细胞恶性表型，而 MTA1 升高则逆转了抑制作用。最后，沉默 circUSPL1 通过海绵 miR-1296-5p 和调节 MTA1 抑制肿瘤生长。
circUSPL1 缺失通过靶向 miR-1296-5p 减少 MTA1 来抑制 BC 细胞恶性表型，这可能为 BC 治疗提供理论依据。
