Yuan Mengzhen, Zhang Jun, He Yuxin, Yi Guangming, Rong Liwen, Zheng Liangjian, Zhan Tingting, Zhou Congming
Department of Oncology, The Third People's Hospital of Chengdu, No.82, Qinglong Street, Qingyang District, Chengdu, 610031, Sichuan, China.
The Third Hospital of Mianyang, Sichuan Mental Health Center, Mianyang, Sichuan, China.
Arch Gynecol Obstet. 2022 Nov;306(5):1643-1655. doi: 10.1007/s00404-022-06481-9. Epub 2022 Mar 14.
Circular RNAs (circRNAs) have been reported to function as vital regulators in cancers, including triple-negative breast cancer (TNBC). This study aimed to explore the role of circ_0062558 in TNBC.
The real-time quantitative polymerase chain reaction (RT-qPCR) was conducted to quantify the expressions of circ_0062558, microRNA-876-3p (miR-876-3p), and solute carrier family 1 (neutral amino acid transporter), member 5 (SLC1A5) in TNBC tissues and cells. 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide (MTT), thymidine analog 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, wound healing, and Transwell assays were employed for cell phenotype analyses. Protein expression was tested by western blot analysis. Dual-luciferase reporter was used to confirm the association among circ_0062558, miR-876-3p, and SLC1A5 in TNBC. Xenograft experiments were performed to elucidate the function of circ_0062558 in vivo.
TNBC tissues and cells showed the higher level of circ_0062558 when compared with control samples. Downregulation of circ_0062558 inhibited proliferation, migration, invasion, and glutamine metabolism, while enhanced apoptosis of TNBC cells, and silencing of circ_0062558 also inhibited the growth of tumor in vivo. MiR-876-3p was confirmed as a target of circ_0062558, and circ_0062558 knockdown repressed TNBC cell malignant behaviors by increasing miR-876-3p. Furthermore, miR-876-3p inhibited malignant behaviors of TNBC cells by down-regulating SLC1A5, a newly identified target of miR-876-3p.
Circ_0062558 promoted TNBC progression by enhancing proliferation, survival, migration, invasion, and glutamine metabolism via miR-876-3p/SLC1A5 axis, which was helpful for understanding the carcinogenic roles of circ_0062558.
环状RNA（circRNAs）已被报道在包括三阴性乳腺癌（TNBC）在内的癌症中发挥重要调节作用。本研究旨在探讨circ_0062558在TNBC中的作用。
采用实时定量聚合酶链反应（RT-qPCR）来定量TNBC组织和细胞中circ_0062558、微小RNA-876-3p（miR-876-3p）和溶质载体家族1（中性氨基酸转运体）成员5（SLC1A5）的表达。使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基-2H-四唑溴盐（MTT）、胸腺嘧啶类似物5-乙炔基-2'-脱氧尿苷（EdU）、流式细胞术、伤口愈合实验和Transwell实验进行细胞表型分析。通过蛋白质免疫印迹分析检测蛋白质表达。使用双荧光素酶报告基因来证实TNBC中circ_0062558、miR-876-3p和SLC1A5之间的关联。进行异种移植实验以阐明circ_0062558在体内的功能。
与对照样本相比，TNBC组织和细胞中circ_0062558水平更高。circ_0062558的下调抑制了TNBC细胞的增殖、迁移、侵袭和谷氨酰胺代谢，同时增强了细胞凋亡，并且circ_0062558的沉默也抑制了体内肿瘤的生长。miR-876-3p被证实为circ_0062558的靶标，circ_0062558敲低通过增加miR-876-3p来抑制TNBC细胞的恶性行为。此外，miR-876-3p通过下调SLC1A5（miR-876-3p新发现的靶标）来抑制TNBC细胞的恶性行为。
Circ_0062558通过miR-876-3p/SLC1A5轴增强增殖、存活、迁移、侵袭和谷氨酰胺代谢，从而促进TNBC进展，这有助于理解circ_0062558的致癌作用。
