Case Control Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2020; 26(15): 1775-1791
Published online Apr 21, 2020. doi: 10.3748/wjg.v26.i15.1775
Value of long non-coding RNA Rpph1 in esophageal cancer and its effect on cancer cell sensitivity to radiotherapy
Zhen-Yang Li, Hui-Fen Li, Ying-Ying Zhang, Xue-Lan Zhang, Bing Wang, Jiang-Ting Liu
Zhen-Yang Li, Hui-Fen Li, Ying-Ying Zhang, Xue-Lan Zhang, Jiang-Ting Liu, Department of Scientific Research, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong Province, China
Bing Wang, Department of Gastroenterology, Qilu Hospital of Shandong University, Jinan 250012, Shandong Province, China
Author contributions: Liu JT and Li ZY performed the majority of experiments and analyzed the data; Li HF and Zhang YY performed the molecular investigations; Zhang XL and Wang B designed and coordinated the research; Li ZY and Li HF wrote the paper.
Institutional review board statement: This study was reviewed and approved by the Qilu Hospital of Shandong University Ethics Committee.
Informed consent statement: All patients in our study provided informed consent.
Conflict-of-interest statement: The authors declare no conflict of interest.
Data sharing statement: No additional data are available.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: Jiang-Ting Liu, PhD, Professor, Department of Scientific Research, Shandong University of Traditional Chinese Medicine, No. 4655, Changqing District, Jinan 250355, Shandong Province, China. liccpk0@163.com
Received: December 11, 2019
Peer-review started: December 11, 2019
First decision: January 13, 2020
Revised: January 23, 2020
Accepted: March 19, 2020
Article in press: March 19, 2020
Published online: April 21, 2020
ARTICLE HIGHLIGHTS
Research background

As a common digestive tract tumor, esophageal cancer is typically treated by radiotherapy. Poor responses to radiotherapy in most patients are prone to causing local radiotherapy failure. It is therefore essential to find new radiosensitizers to enhance the response of cancer cells to radiotherapy and increase the survival rate of esophageal cancer patients with radiation resistance. The long non-coding RNA (lncRNA) Rpph1 is highly expressed in human gastric cancer tissues, which also decreases breast cancer cell proliferation as well as tumorigenesis. In fact, the expression of lncRNA Rpph1 in esophageal cancer and its relationship with radio-sensitivity have not been thoroughly investigated.

Research motivation

LncRNA Rpph1 is found abnormally expressed in a variety of cancers. The possibility that Rpph1 impacts the radio-sensitivity of esophageal cancer cells requires more research.

Research objectives

This study was intended to reveal the value of lncRNA Rpph1 in esophageal cancer as well as its effect on cell sensitivity to radiotherapy.

Research methods

We initially detected the expression of lncRNA Rpph1 in esophageal cancer tissue samples obtained surgically. Subsequently, siRNA-NC or siRNA-Rpph1 was transfected into esophageal cancer cell lines, and a blank control group was set where cells were not transfected with anything. Consequently, we analyzed the effect of Rpph1 on the biological behavior of esophageal cancer cells exposed to irradiation.

Research results

We found that Rpph1 is highly expressed in esophageal cancer. Rpph1 can be applied for the diagnosis of esophageal cancer and identify the pathological characteristics of patients. The results of 3-year survival supported patients with low Rpph1 expression over those with high Rpph1 expression (P < 0.05). Cytological studies indicated that silencing the expression of Rpph1 contributed to the enhancement of radio-sensitivity of esophageal cancer cells and cell apoptosis via regulating apoptosis-linked proteins, thus relieving the radiation-induced G2/M phase cell cycle arrest. It also helped restrain cell proliferation and migration and regulate the expression of epithelial-mesenchymal transition (EMT)-related proteins.

Research conclusions

Rpph1 is highly expressed in esophageal cancer. Silencing Rpph1 expression has an influence on the biological behavior of tumor cells and the enhancement of radio-sensitivity.

Research perspectives

This study revealed the value of Rpph1 in the diagnosis of esophageal cancer and concluded that silencing Rpph1 expression can enhance the radiotherapy of tumor cells, illuminating a new target for the future treatment of esophageal cancer.