Department of Oncology, Chongqing Three Gorges Central Hospital and Chongqing University Three Gorges Hospital, No. 165, Xin Cheng Road, Wanzhou District, Chongqing, 404000, China.
Dig Dis Sci. 2021 Dec;66(12):4290-4301. doi: 10.1007/s10620-020-06802-5. Epub 2021 Jan 15.
Circular RNA (circRNA) has been shown to be closely associated with cancer progression, including gastric cancer (GC). However, the function of circ_0004104 in GC progression has not been clarified.
The purpose of this study was to explore the role of circ_0004104 in GC progression.
The expression levels of circ_0004104, miR-539-3p, and ring finger protein 2 (RNF2) were assessed using quantitative real-time polymerase chain reaction. Cell proliferation was measured by 3-(4,5-dimethyl-2 thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, and cell migration and invasion were detected using transwell assay. The levels of glutamine, glutamate, and α-ketoglutarate were determined to evaluate the glutaminolysis of cells, and the protein levels of glutaminolysis-related markers and RNF2 were detected using western blot analysis. Furthermore, Dual-Luciferase Reporter Assay was employed to assess the interaction between miR-539-3p and circ_0004104 or RNF2. Animal experiments were carried out to evaluate the effect of circ_0004104 silencing on GC tumor growth in vivo.
Circ_0004104 was upregulated in GC, and its knockdown repressed the proliferation, metastasis, and glutaminolysis of GC cells in vitro and reduced GC tumor growth in vivo. Furthermore, we discovered that circ_0004104 could sponge miR-539-3p and miR-539-3p could target RNF2. The rescue experiments suggested that miR-539-3p inhibitor could reverse the suppressive effect of circ_0004104 silencing on GC progression, and RNF2 overexpression also reversed the inhibition effect of miR-539-3p mimic on GC progression.
Circ_0004104 accelerated GC progression via regulating the miR-539-3p/RNF2 axis, indicating that circ_0004104 might be a potential therapeutic target for GC.
环状 RNA（circRNA）与癌症进展密切相关，包括胃癌（GC）。然而，circ_0004104 在 GC 进展中的作用尚未阐明。
本研究旨在探讨 circ_0004104 在 GC 进展中的作用。
采用实时定量聚合酶链反应检测 circ_0004104、miR-539-3p 和环指蛋白 2（RNF2）的表达水平。采用 3-(4,5-二甲基-2 噻唑基)-2,5-二苯基-2-H-四唑溴盐法检测细胞增殖，用 Transwell 检测细胞迁移和侵袭。测定细胞内谷氨酰胺、谷氨酸和α-酮戊二酸的水平，以评估细胞的谷氨酰胺分解代谢，并用 Western blot 分析检测谷氨酰胺分解代谢相关标志物和 RNF2 的蛋白水平。此外，采用双荧光素酶报告基因检测评估 miR-539-3p 与 circ_0004104 或 RNF2 的相互作用。进行动物实验评估 circ_0004104 沉默对体内 GC 肿瘤生长的影响。
circ_0004104 在 GC 中上调，其敲低抑制 GC 细胞在体外的增殖、迁移和谷氨酰胺分解代谢，并减少体内 GC 肿瘤生长。此外，我们发现 circ_0004104 可以海绵吸附 miR-539-3p，而 miR-539-3p 可以靶向 RNF2。 rescue 实验表明，miR-539-3p 抑制剂可以逆转 circ_0004104 沉默对 GC 进展的抑制作用，而 RNF2 过表达也逆转了 miR-539-3p 模拟物对 GC 进展的抑制作用。
circ_0004104 通过调节 miR-539-3p/RNF2 轴加速 GC 进展，表明 circ_0004104 可能成为 GC 的潜在治疗靶点。
