Purpose Circular RNAs (circRNAs) are a new class of RNA molecules whose function is largely unknown. There is a growing evidence that circRNAs play an important regulatory role in the progression of a variety of human cancers. However, the exact roles and the mechanisms of circRNAs in gastric cancer are not clear. In this study, we aimed to elucidate the mechanism of hsa_circ_0005556. Materials and Methods Real-time quantitative polymerase chain reaction was used to detect the expression of hsa_circ_0005556, miR-4270, and matrix metalloproteinase-19 (MMP19) in gastric cancer tissues and cell lines. The expression of hsa_circ_0005556 in gastric cancer cells was silenced by lentivirus, and cell proliferation, invasion, migration, and tumorigenesis in nude mice were assessed to evaluate the function of hsa_circ_0005556 in gastric cancer. Results The expression of hsa_circ_0005556 in gastric cancer tissues and gastric cancer cell lines was higher compared to normal controls. In vitro, the downregulation of hsa_circ_0005556 significantly inhibited proliferation, migration, and invasion of gastric cancer cells. In vivo, the downregulation of hsa_circ_0005556 suppressed tumor growth in nude mice. Conclusions Our study shows that the hsa_circ_0005556/miR-4270/MMP19 axis is involved in proliferation, migration, and invasion of gastric cancer cells through the competing endogenous RNA (ceRNA) mechanism.

中文翻译：

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环状 RNA hsa_circ_0005556 通过海绵状 miR-4270 增加 MMP19 表达加速胃癌进展

目的 环状 RNA (circRNA) 是一类新的 RNA 分子，其功能在很大程度上是未知的。越来越多的证据表明，circRNA 在多种人类癌症的进展中发挥着重要的调节作用。然而，circRNA在胃癌中的确切作用和机制尚不清楚。在这项研究中，我们旨在阐明 hsa_circ_0005556 的机制。材料与方法 实时定量聚合酶链反应检测胃癌组织和细胞系中hsa_circ_0005556、miR-4270和基质金属蛋白酶19（MMP19）的表达。慢病毒沉默hsa_circ_0005556在胃癌细胞中的表达，并在裸鼠体内评估细胞增殖、侵袭、迁移和成瘤情况，评价hsa_circ_0005556在胃癌中的作用。结果hsa_circ_0005556在胃癌组织和胃癌细胞株中的表达高于正常对照组。在体外，hsa_circ_0005556的下调显着抑制了胃癌细胞的增殖、迁移和侵袭。在体内，hsa_circ_0005556 的下调抑制了裸鼠的肿瘤生长。结论 我们的研究表明，hsa_circ_0005556/miR-4270/MMP19 轴通过竞争性内源性 RNA (ceRNA) 机制参与胃癌细胞的增殖、迁移和侵袭。hsa_circ_0005556 的下调抑制了裸鼠的肿瘤生长。结论 我们的研究表明，hsa_circ_0005556/miR-4270/MMP19 轴通过竞争性内源性 RNA (ceRNA) 机制参与胃癌细胞的增殖、迁移和侵袭。hsa_circ_0005556 的下调抑制了裸鼠的肿瘤生长。结论 我们的研究表明，hsa_circ_0005556/miR-4270/MMP19 轴通过竞争性内源性 RNA (ceRNA) 机制参与胃癌细胞的增殖、迁移和侵袭。