Basic Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Dec 14, 2018; 24(46): 5234-5245
Published online Dec 14, 2018. doi: 10.3748/wjg.v24.i46.5234
MicroRNA-15a - cell division cycle 42 signaling pathway in pathogenesis of pediatric inflammatory bowel disease
Wen-Juan Tang, Kai-Yue Peng, Zi-Fei Tang, Yu-Huan Wang, Ai-Juan Xue, Ying Huang
Wen-Juan Tang, Kai-Yue Peng, Zi-Fei Tang, Yu-Huan Wang, Ai-Juan Xue, Ying Huang, Department of Gastroenterology, Children’s Hospital of Fudan University, Shanghai 201102, China
Author contributions: Huang Y designed the study, coordinated and supervised data collection, and critically reviewed and revised the manuscript; Tang WJ performed the research, analyzed data, and wrote the initial manuscript; Peng KY and Xue AJ contributed to cell culture and some data analyses; Tang ZF and Wang YH contributed to clinical data analyses. All authors approved the final manuscript to be submitted for publication.
Supported by the National Natural Science Foundation of Shanghai, No. 201540068.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Children’s Hospital of Fudan University, and written informed consent was obtained from all patients for the use of their tissues.
Conflict-of-interest statement: The authors have no conflict of interest to disclose.
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 to: Ying Huang, MD, PhD, Chief Doctor, Director, Professor, Department of Gastroenterology, Children’s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102, China. 15111240011@fudan.edu.cn
Telephone: +86-21-64931727 Fax: +86-21-64931990
Received: September 4, 2018
Peer-review started: September 4, 2018
First decision: October 4, 2018
Revised: October 31, 2018
Accepted: November 7, 2018
Article in press: November 8, 2018
Published online: December 14, 2018
Processing time: 100 Days and 17 Hours
Abstract
AIM

To determine whether cell division cycle (Cdc)42 is regulated by microRNA (miR)-15a in the development of pediatric inflammatory bowel disease (IBD).

METHODS

We cultured 293T cells, used plasmids and performed dual-luciferase assay to determine whether Cdc42 is a miR-15a target gene. We cultured Caco-2 cells, and stimulated them with tumor necrosis factor (TNF)-α. We then employed lentiviruses to alter the expression of miR-15a and Cdc42. We performed quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunofluorescence to determine whether Cdc42 is regulated by miR-15a in Caco-2 cells. Finally, we collected ileocecal tissue by endoscopy from patients and performed qRT-PCR to examine the expression of miR-15a and Cdc42 in pediatric IBD patients.

RESULTS

Target Scan and dual-luciferase assay revealed that Cdc42 was a miR-15a target gene. MiR-15a expression increased (P = 0.0038) and Cdc42 expression decreased (P = 0.0013) in cells stimulated with TNF-α, and the expression of the epithelial junction proteins zona occludens (ZO)-1 (P < 0.05) and E-cadherin (P < 0.001) decreased. Cdc42 levels decreased in miR-15a-mimic cells (P < 0.001) and increased in miR-15a inhibitor cells (P < 0.05). ZO-1 and E-cadherin decreased in miR-15a-mimic cells (P < 0.001) but not in the miR-15a inhibitor + TNF-α cells. In Lv-Cdc42 + TNF-α cells, ZO-1 and E-cadherin expression increased compared to the Lv-Cdc42-NC + TNF-α (P < 0.05) or miR-15a-mimic cells (P < 0.05). Fifty-four pediatric IBD patients were included in this study, 21 in the control group, 19 in the Crohn’s disease (CD) active (AC) group, seven in the CD remission (RE) group, and seven in the ulcerative colitis (UC) group. MiR-15a increased and Cdc42 decreased in the CD AC group compared to the control group (P < 0.05). miR-15a decreased and Cdc42 increased in the CD RE group compared to the CD AC group (P < 0.05). miR-15a was positively correlated with the Pediatric Crohn’s disease Activity Index (PCDAI) (P = 0.006), while Cdc42 was negatively correlated with PCDAI (P = 0.0008). Finally, miR-15a expression negatively correlated with Cdc42 in pediatric IBD patients (P = 0.0045).

CONCLUSION

MiR-15a negatively regulates epithelial junctions through Cdc42 in Caco-2 cells and pediatric IBD patients.

Keywords: Pediatric inflammatory bowel disease; MicroRNA-15a; Cell division cycle 42; Zona occludens-1; E-cadherin

Core tip: This study aimed to determine whether cell division cycle (Cdc)42 was regulated by microRNAs in pediatric inflammatory bowel disease (IBD) development. We studied microRNA (miR)-15a - Cdc42 signaling in pediatric IBD patients and found that miR-15a negatively regulated Cdc42 in pediatric IBD patients, and both were strongly correlated with the severity of IBD. Additionally, this study provides evidence that Cdc42 is a target gene of miR-15a, and this will provide a critical clue for understanding IBD development.