miR-219-5p has been reported to act as either a tumor suppressor or a tumor promoter in different cancers by targeting different genes. In this study, we demonstrated that miR-219-5p negatively regulated the expression of TBXT , a known EMT inducer, by directly binding to TBXT 3'-untranslated region. As a result of its inhibition on TBXT expression, miR-219-5p suppressed epithelial-mesenchymal transition (EMT) and cell migration and invasion in breast cancer cells. The re-introduction of TBXT in miR-219-5p overexpressing cells decreased the inhibitory effects of miR-219 on EMT and cell migration and invasion. Moreover, miR-219-5p decreased breast cancer stem cell (CSC) marker genes expression and reduced the mammosphere forming capability of cells. Overall, our study highlighted that TBXT is a novel target of miR-219-5p. By suppressing TBXT, miR-219-5p plays an important role in EMT and cell migration and invasion of breast cancer cells.

中文翻译：

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miR-219-5p 靶向 TBXT 并抑制乳腺癌细胞 EMT 和细胞迁移和侵袭。

据报道，miR-219-5p 通过靶向不同的基因在不同的癌症中充当肿瘤抑制因子或肿瘤促进因子。在这项研究中，我们证明了 miR-219-5p 通过直接与 TBXT 3'-非翻译区结合来负调节已知 EMT 诱导剂 TBXT 的表达。由于其对 TBXT 表达的抑制作用，miR-219-5p 抑制了乳腺癌细胞中的上皮间质转化 (EMT) 和细胞迁移和侵袭。在 miR-219-5p 过表达细胞中重新引入 TBXT 降低了 miR-219 对 EMT 和细胞迁移和侵袭的抑制作用。此外，miR-219-5p 降低了乳腺癌干细胞 (CSC) 标记基因的表达并降低了细胞的乳腺球形成能力。总体而言，我们的研究强调 TBXT 是 miR-219-5p 的新靶点。通过抑制 TBXT，