Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea.
Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Br J Cancer. 2020 Sep;123(7):1123-1130. doi: 10.1038/s41416-020-0940-5. Epub 2020 Jun 17.
Epithelial-mesenchymal transition (EMT) is the most common cause of death in colorectal cancer (CRC). In this study, we investigated the functional roles of miRNA-17-5p in EMT of CRC cells.
In order to determine if miRNA-17-5p regulated EMT, the precursors and inhibitors of miR-17-5p were transduced into four CRC cells. To evaluate the regulatory mechanism, we performed argonaute 2 (Ago2) immunoprecipitation (IP) and luciferase assay. In addition, we used an intra-splenic injection mouse model of BALB/c nude mice to investigate the metastatic potential of miRNA-17-5p in vivo.
The miRNA-17-5p expression was lower in primary CRC tissues with metastasis than in primary CRC tissues without metastasis in our RNA sequencing data of patient tissue. Real-time quantitative PCR revealed that miRNA-17-5p was inversely correlated with that of vimentin in five CRC cell lines. Over-expression of miRNA-17-5p decreased vimentin expression and inhibited cell migration and invasion in both LoVo and HT29 cells. However, inhibition of miRNA-17-5p showed the opposite effect. Ago2 IP and luciferase assay revealed that miRNA-17-5p directly bound to the 3'UTR of VIM mRNA. Furthermore, miRNA-17-5p inhibited the metastasis of CRC into liver in vivo.
Our results demonstrated that miRNA-17-5p regulates vimentin expression, thereby regulating metastasis of CRC.
上皮-间充质转化（EMT）是结直肠癌（CRC）最常见的死亡原因。在本研究中，我们研究了 miRNA-17-5p 在 CRC 细胞 EMT 中的功能作用。
为了确定 miRNA-17-5p 是否调节 EMT，我们将 miR-17-5p 的前体和抑制剂转导到四种 CRC 细胞中。为了评估调节机制，我们进行了 Argonaute 2（Ago2）免疫沉淀（IP）和荧光素酶测定。此外，我们使用 BALB/c 裸鼠脾内注射小鼠模型在体内研究 miRNA-17-5p 的转移潜力。
我们的患者组织 RNA 测序数据显示，具有转移的原发性 CRC 组织中的 miRNA-17-5p 表达低于没有转移的原发性 CRC 组织。实时定量 PCR 显示 miRNA-17-5p 与五个 CRC 细胞系中的波形蛋白呈负相关。miRNA-17-5p 的过表达降低了 LoVo 和 HT29 细胞中波形蛋白的表达，并抑制了细胞迁移和侵袭。然而，抑制 miRNA-17-5p 则表现出相反的效果。Ago2 IP 和荧光素酶测定显示 miRNA-17-5p 可直接与 VIM mRNA 的 3'UTR 结合。此外，miRNA-17-5p 抑制 CRC 在体内向肝脏转移。
我们的结果表明，miRNA-17-5p 调节波形蛋白的表达，从而调节 CRC 的转移。
