The aim of this study was to investigate the roles and potential mechanisms of long non-coding RNA (lncRNA) taurine upregulated gene 1 (TUG1) in the proliferation, migration, and invasion of Ewing's sarcoma cells. RT-qPCR was used to detect the expression of TUG1, microRNA-199a-3p (miR-199a-3p), and musashi2 (MSI2) in Ewing's sarcoma tissues and cell lines. Kaplan-Meier overall survival curves showed the survival rates of Ewing's sarcoma patients with high and low expression of TUG1. The association between the expressions of TUG1/MSI2 and miR-199a-3p in Ewing's sarcoma tissues was assessed by Pearson's correlation analysis. Cell proliferation, migration, and invasion were detected by CCK8 assay and Transwell assay, respectively. The protein level of MSI2 was determined using western blotting. The interaction between TUG1/MSI2 and miR-199a-3p was validated by the dual-luciferase reporter assay. The levels of TUG1 and MSI2 were increased, while the level of miR-199a-3p was decreased in Ewing's sarcoma tissues and cells. High expression of TUG1 or MSI2 indicated a decreased overall survival rate of Ewing's sarcoma patients. TUG1/MSI2 level was negatively correlated with miR-199a-3p level. While TUG1 level was positively correlated with MSI2 level. In Ewing sarcoma cells, knockdown of TUG1/MSI2 or overexpression of miR-199a-3p inhibited cell proliferation, migration, and invasion, whereas the overexpression of TUG1/MSI2 presented the opposite results. TUG1 functioned as a competing endogenous RNA to regulate MSI2 expression by sponging miR-199a-3p. Finally, miR-199a-3p inhibitor or MSI2 overexpression counteracted the TUG1 knockdown-mediated inhibitory effect on Ewing's sarcoma cell proliferation, migration, and invasion. TUG1 promotes proliferation, migration, and invasion of Ewing's sarcoma cells via sequestering miR-199a-3p to enhance the MSI2 expression, suggesting that TUG1 might be a potential target for treating Ewing's sarcoma.

中文翻译：

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LncRNA TUG1通过miR-199a-3p-MSI2信号通路促进尤文氏肉瘤细胞的增殖，迁移和侵袭。

这项研究的目的是调查长期非编码RNA（lncRNA）牛磺酸上调基因1（TUG1）在尤文氏肉瘤细胞的增殖，迁移和侵袭中的作用和潜在机制。使用RT-qPCR检测Ewing肉瘤组织和细胞系中TUG1，microRNA-199a-3p（miR-199a-3p）和musashi2（MSI2）的表达。Kaplan-Meier总体生存曲线显示了Ewing肉瘤患者TUG1高表达和低表达的生存率。通过皮尔逊相关分析评估了尤因肉瘤组织中TUG1 / MSI2和miR-199a-3p的表达之间的关联。细胞增殖，迁移和侵袭分别通过CCK8测定法和Transwell测定法检测。使用蛋白质印迹法确定MSI2的蛋白水平。TUG1 / MSI2和miR-199a-3p之间的相互作用已通过双荧光素酶报告基因分析验证。Ewing肉瘤组织和细胞中TUG1和MSI2的水平升高，而miR-199a-3p的水平降低。TUG1或MSI2的高表达表明尤因氏肉瘤患者的总生存率降低。TUG1 / MSI2水平与miR-199a-3p水平呈负相关。TUG1水平与MSI2水平呈正相关。在尤因肉瘤细胞中，敲低TUG1 / MSI2或过表达miR-199a-3p抑制细胞增殖，迁移和侵袭，而过表达TUG1 / MSI2则呈现相反的结果。TUG1通过竞争miR-199a-3p作为竞争性内源RNA来调节MSI2表达。最后，miR-199a-3p抑制剂或MSI2过表达抵消了TUG1敲低介导的对尤因肉瘤细胞增殖，迁移和侵袭的抑制作用。TUG1通过螯合miR-199a-3p增强MSI2表达来促进Ewing肉瘤细胞的增殖，迁移和侵袭，表明TUG1可能是治疗Ewing肉瘤的潜在靶标。