Sui Chao, Qu Wei, Lian Yanfen, Feng Chuanbo, Zhan Yi
Department of Oncology, Weihai Central Hospital.
Department of Oncology, Shidao People's Hospital Of Rongcheng, Weihai, Shandong.
Anticancer Drugs. 2021 Sep 1;32(8):829-841. doi: 10.1097/CAD.0000000000001076.
Circular RNAs (circRNAs) are revealed to regulate breast cancer progression. This study aimed to investigate hsa_circ_0069094-mediated effects on breast cancer cell malignancy. Quantitative real time PCR was employed to evaluate the expressions of hsa_circ_0069094, miR-661 and high mobility group A1 (HMGA1). Western blot was performed to determine the protein expression of HMGA1 and proliferating cell nuclear antigen. Breast cancer malignant progressions were explained by cell counting kit-8 proliferation, cell colony formation, flow cytometry analysis, wound-healing and transwell assays. Cell glycolysis was assessed by detecting glucose take, lactate production and hexokinase 2 (HK2) protein level. The target relationship between miR-661 and hsa_circ_0069094 or HMGA1 was predicted by circular RNA interactome and targetscan online databases, and identified by dual-luciferase reporter and RNA immunoprecipitation assay. The effects of hsa_circ_0069094 knockdown on breast cancer growth in vivo were elucidated by in vivo tumor formation assay. Hsa_circ_0069094 and HMGA1 expression were significantly upregulated, while miR-661 expression level was downregulated in breast cancer tissues and cells relative to adjacent normal breast tissues or MCF-10A cells. Functionally, hsa_circ_0069094 knockdown inhibited cell glycolysis, proliferation, migration and invasion, whereas induced cell apoptosis in breast cancer, which was decreased by miR-661 inhibitor. Mechanistically, hsa_circ_0069094 regulated HMGA1 by sponging miR-661. Furthermore, hsa_circ_0069094 knockdown repressed tumor formation in vivo. Collectively, hsa_circ_0069094 knockdown repressed breast cancer cell carcinogenesis and cell glycolysis by regulating HMGA1 through sponging miR-661, which provided a new insight for studying the mechanism of hsa_circ_0069094 in modulating breast cancer development.
环状RNA（circRNAs）被发现可调节乳腺癌进展。本研究旨在探究hsa_circ_0069094对乳腺癌细胞恶性程度的影响。采用定量实时聚合酶链反应评估hsa_circ_0069094、miR-661和高迁移率族蛋白A1（HMGA1）的表达。进行蛋白质印迹法以测定HMGA1和增殖细胞核抗原的蛋白质表达。通过细胞计数试剂盒-8增殖、细胞集落形成、流式细胞术分析、伤口愈合和Transwell实验来阐述乳腺癌的恶性进展。通过检测葡萄糖摄取、乳酸生成和己糖激酶2（HK2）蛋白水平来评估细胞糖酵解。通过环状RNA相互作用组和TargetScan在线数据库预测miR-661与hsa_circ_0069094或HMGA1之间的靶标关系，并通过双荧光素酶报告基因和RNA免疫沉淀实验进行鉴定。通过体内肿瘤形成实验阐明hsa_circ_0069094敲低对体内乳腺癌生长的影响。相对于相邻正常乳腺组织或MCF-10A细胞，hsa_circ_0069094和HMGA1在乳腺癌组织和细胞中的表达显著上调，而miR-661表达水平下调。在功能上，hsa_circ_0069094敲低抑制了乳腺癌细胞的糖酵解、增殖、迁移和侵袭，同时诱导细胞凋亡，而miR-661抑制剂可降低这种作用。机制上，hsa_circ_0069094通过吸附miR-661来调节HMGA1。此外，hsa_circ_0069094敲低可抑制体内肿瘤形成。总的来说，hsa_circ_0069094敲低通过吸附miR-661调节HMGA1，从而抑制乳腺癌细胞的致癌作用和细胞糖酵解，这为研究hsa_circ_0069094调节乳腺癌发展的机制提供了新的见解。
