miR-675 在胃癌中经常过表达，通过靶向一种有效的抗肿瘤基因 PITX1 促进细胞增殖和侵袭。
MiR-675 is frequently overexpressed in gastric cancer and enhances cell proliferation and invasion via targeting a potent anti-tumor gene PITX1.
机构信息
Department Of Gastroenterology, The Fourth People's Hospital of Jinan, Jinan, Shandong, PR China.
Sterrilization And Suplly Center, The Fourth People's Hospital of Jinan, Jinan, Shandong, PR China.
出版信息
Cell Signal. 2019 Oct;62:109352. doi: 10.1016/j.cellsig.2019.109352. Epub 2019 Jun 28.
BACKGROUND
Gastric cancer (GC) is a common malignancy around the world. Irregular expression of microRNAs (miRNAs) contributes to the progression of malignancies. Our study illustrated that miR-675 facilitates GC proliferation and invasion via targeting paired-like homeodomain transcription factor 1 (PITX1) and promoting epithelial-mesenchymal transition (EMT) as well as Wnt/β-catenin signaling pathway.
METHODS
We collected the RNA-seq data of GC and normal stomach tissues from TCGA database to analyze the expression of miR-675 and PITX1. Kaplan-Meier plotter on line tool was used to analyze the association between miR-675 or PITX1 expression and the overall survival of GC patients. The biological function of miR-675 in GC cells was evaluated via altering its expression using miR-675 agomiR or antamiR. Dual-luciferase reporter assay was applied for verifying whether miR-675 could direct bind to 3'UTR of PITX1. Rescue assays were applied for characterizing the effects of miR-675/PITX1 axis on GC growth and invasion. Western blot was performed to evaluate the protein expression levels of PITX1, EMT-related and Wnt signaling-related proteins.
RESULTS
Our results showed that miR-675 is up-regulated and predictive of worse prognosis in GC patients. Overexpression of miR-675 in AGS cells notably promoted cell proliferation, migration and invasion, whilst down-regulation of miR-675 in SGC-7901 cells gained the opposite results. PITX1 is down-regulated in GC and identified as a direct target of miR-675. Overexpression of PITX1 in AGS cells reverses cell viability and invasion that enhanced by miR-675 up-regulation. Conversely, depletion of PITX1 in SGC-7901 cells rescues cell viability and invasion that inhibited by miR-675 down-regulation. Western bolt results revealed that miR-675 positively regulated EMT and Wnt/β-catenin signaling pathway in GC cells via targeting PITX1.
CONCLUSIONS
Our study emphasized the functional mechanism of miR-675 in GC and intimated that miR-675/PITX1 axis possibly affects proliferative and invasive properties of GC cells via regulating EMT and Wnt/β-catenin signaling pathway. Furthermore, miR-675 and PITX1 may be served as early diagnostic markers as well as therapeutic targets for GC.
背景
胃癌（GC）是一种常见的恶性肿瘤。微小 RNA（miRNA）的异常表达有助于恶性肿瘤的进展。我们的研究表明，miR-675 通过靶向同源异型盒转录因子 1（PITX1）促进上皮间质转化（EMT）和 Wnt/β-catenin 信号通路，促进 GC 增殖和侵袭。
方法
我们从 TCGA 数据库中收集了 GC 和正常胃组织的 RNA-seq 数据，以分析 miR-675 和 PITX1 的表达。Kaplan-Meier plotter 在线工具用于分析 miR-675 或 PITX1 表达与 GC 患者总生存期的关系。通过使用 miR-675 agomiR 或 antamiR 改变其表达来评估 miR-675 在 GC 细胞中的生物学功能。双荧光素酶报告基因实验用于验证 miR-675 是否可以直接结合 PITX1 的 3'UTR。通过恢复实验来研究 miR-675/PITX1 轴对 GC 生长和侵袭的影响。Western blot 用于评估 PITX1、EMT 相关和 Wnt 信号相关蛋白的表达水平。
结果
我们的结果表明，miR-675 在 GC 患者中上调，并与预后不良相关。AGS 细胞中 miR-675 的过表达显著促进细胞增殖、迁移和侵袭，而 SGC-7901 细胞中 miR-675 的下调则获得相反的结果。PITX1 在 GC 中下调，被鉴定为 miR-675 的直接靶标。AGS 细胞中 PITX1 的过表达逆转了 miR-675 上调增强的细胞活力和侵袭。相反，SGC-7901 细胞中 PITX1 的耗竭挽救了 miR-675 下调抑制的细胞活力和侵袭。Western blot 结果表明，miR-675 通过靶向 PITX1 正向调节 GC 细胞中的 EMT 和 Wnt/β-catenin 信号通路。
结论
我们的研究强调了 miR-675 在 GC 中的功能机制，并暗示 miR-675/PITX1 轴可能通过调节 EMT 和 Wnt/β-catenin 信号通路影响 GC 细胞的增殖和侵袭特性。此外，miR-675 和 PITX1 可能作为 GC 的早期诊断标志物和治疗靶点。
Zotero 插件