Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 21, 2015; 21(31): 9337-9347
Published online Aug 21, 2015. doi: 10.3748/wjg.v21.i31.9337
MiR-30b suppresses tumor migration and invasion by targeting EIF5A2 in gastric cancer
Shu-Bo Tian, Jian-Chun Yu, Yu-Qin Liu, Wei-Ming Kang, Zhi-Qiang Ma, Xin Ye, Chao Yan
Shu-Bo Tian, Jian-Chun Yu, Wei-Ming Kang, Zhi-Qiang Ma, Xin Ye, Chao Yan, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
Yu-Qin Liu, Cell Centre, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing 100730, China
Author contributions: Tian SB and Yu JC designed the research; Tian SB, Ye X and Yan C performed the experiments; Liu YQ, Kang WM and Ma ZQ analyzed the data; Tian SB and Yan C wrote the paper.
Supported by Beijing Municipal Natural Science Foundation of China, No. 7132209; and The Capital Health Research and Development of Special, No. 2014-3-4014.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jian-Chun Yu, Professor, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. yujch_pumch@126.com
Telephone: +86-10-69152215 Fax: +86-10-69152215
Received: March 11, 2015
Peer-review started: March 12, 2015
First decision: March 26, 2015
Revised: June 17, 2015
Accepted: July 8, 2015
Article in press: July 8, 2015
Published online: August 21, 2015
Processing time: 162 Days and 13.4 Hours
Abstract

AIM: To elucidate the potential biological role of miR-30b in gastric cancer and investigate the underlying molecular mechanisms of miR-30b to inhibit metastasis of gastric cancer cells.

METHODS: The expression of miR-30b was detected in gastric cancer cell lines and samples by reverse transcription-polymerase chain reaction. CCK-8 assays were conducted to explore the impact of miR-30b overexpression on the proliferation of gastric cancer cells. Flow cytometry was used to examine the effect of miR-30b on the apoptosis. Transwell test was used for the migration and invasion assays. Luciferase reporter assays and Western blot were employed to validate regulation of putative target of miR-30b.

RESULTS: The results showed that miR-30b was downregulated in gastric cancer tissues and cancer cell lines and functioned as a tumor suppressor. Overexpression of miR-30b promoted cell apoptosis, and suppressed proliferation, migration and invasion of the gastric cancer cell lines AGS and MGC803. Bioinformatic analysis identified the 3’-untranslated region of eukaryotic translation initiation factor 5A2 (EIF5A2) as a putative binding site of miR-30b. Luciferase reporter assays and Western blot analysis confirmed the EIF5A2 gene as a target of miR-30b. Moreover, expression levels of the EIF5A2 targets E-cadherin and Vimentin were altered following transfection of miR-30b mimics.

CONCLUSION: Our findings describe a link between miR-30b and EIF5A2, which plays an important role in mediating epithelial-mesenchymal transition.

Keywords: miR-30b; Gastric cancer; EIF5A2; Migration; Invasion

Core tip: In this study, we found that miR-30b expression was reduced in gastric cancer cell lines and in gastric cancer tissues. Moreover, we found that miR-30b inhibited gastric cancer cell proliferation, migration, invasion and promoted apoptosis by targeting EIF5A2. Restoration of miR-30b expression could enhance E-cadherin and β-catenin expression and suppress Vimentin expression by targeting EIF5A2 and eventually inhibit the epithelial-to-mesenchymal transition (EMT) process in gastric cancer cells, whereas knockdown of miR-30b promoted cell invasion and EMT in cancer cells.