Basic Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 14, 2019; 25(42): 6299-6310
Published online Nov 14, 2019. doi: 10.3748/wjg.v25.i42.6299
Knockdown of lncRNAXLOC_001659 inhibits proliferation and invasion of esophageal squamous cell carcinoma cells
Feng-Zhi Li, Wen-Qiao Zang
Feng-Zhi Li, Wen-Qiao Zang, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, Henan Province, China
Author contributions: Li FZ and Zang WQ designed the research; Li FZ performed the research; Li FZ and Zang WQ wrote the paper.
Supported by Excellent Youth Development Fund of Zhengzhou University, No. 1621328001.
Institutional review board statement: The study was approved by the ethics committee of Zhengzhou University.
Conflict-of-interest statement: The authors declare that they have no competing interests.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
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/
Corresponding author: Wen-Qiao Zang, PhD, Assistant Professor, College of Basic Medical Sciences, Zhengzhou University, No. 100, Kexue Avenue, Zhengzhou 450001, Henan Province, China. zangwenqiao@zzu.edu.cn
Telephone: +86-371-67781959
Received: July 21, 2019
Peer-review started: July 22, 2019
First decision: August 27, 2019
Revised: September 27, 2019
Accepted: November 1, 2019
Article in press: November 1, 2019
Published online: November 14, 2019
Processing time: 116 Days and 2.8 Hours
Abstract
BACKGROUND

Studies have shown that long non-coding RNAs (lncRNAs) play a key role in almost all key physiological and pathological processes, including different types of malignant tumors. Our previous lncRNA microarray results have shown that lncRNA XLOC_001659 is upregulated in esophageal cancer (EC) tissues, with a fold change of 20.9 relative to normal esophageal tissues. But its effect and the molecular biological mechanisms on proliferation and invasion of EC cells remain unclear.

AIM

To investigate the effect of lncRNA XLOC_001659 on esophageal squamous cell carcinoma (ESCC) cells and explore the molecular biological mechanisms involved.

METHODS

RT-qPCR assay was used to quantify the expression levels of lncRNAXLOC-001659 and miR-490-5p. The proliferative capacity of the cells was determined using CCK8 and colony formation assays, and the effect of lncRNAXLOC-001659 on the invasion of ESCC cells was determined by Transwell assay. Dual-luciferase reporter assay was used to detect the target genes of lncRNAXLOC-001659 and miR-490-5p.

RESULTS

The results of RT-qPCR showed that the expression of lncRNAXLOC_001659 was upregulated in ESCC cells. CCK-8 assay showed that knockdown of lncRNAXLOC_001659 significantly inhibited ESCC cell proliferation. Colony formation and Transwell invasion assays showed that knockdown of lncRNAXLOC_001659 or overexpression of miR-490-5p significantly inhibited ESCC cell growth and invasion. Furthermore, lncRNAXLOC_001659 acts as an endogenous sponge by competitively binding to miR-490-5p to downregulate miR-490-5p. Further results confirmed that miR-490-5p targeted PIK3CA, and the recovery of PIK3CA rescued lncRNAXLOC_001659 knockdown or miR-490-5p overexpression-mediated inhibition of cell proliferation and invasion, which suggested the presence of an lncRNAXLOC_001659/miR-490-5p/PIK3CA regulatory axis.

CONCLUSION

Knockdown of lncRNA XLOC_001659 inhibits proliferation and invasion of ESCC cells via regulation of miR-490-5p/PIK3CA, suggesting that it may play a role in ESCC tumorigenesis and progression.

Keywords: Esophageal squamous cell carcinoma; LncRNAXLOC_001659; MiR-490-5p; PIK3CA; Proliferation; Invasion

Core tip: Studies have shown that long non-coding RNAs (lncRNAs) play a key role in almost all key physiological and pathological processes, including different types of malignant tumors. Our previous lncRNA microarray results have shown that lncRNA XLOC_001659 is upregulated in esophageal squamous cell carcinoma (ESCC) tissues, with a fold change of 20.9 relative to normal esophageal tissues. But its effect and the molecular biological mechanisms on proliferation and invasion of ESCC cells remain unclear. Here we showed that knockdown of lncRNA XLOC_001659 inhibited proliferation and invasion of ESCC cells via regulation of miR-490-5p/PIK3CA, suggesting that it may play a role in ESCC tumorigenesis and progression.