Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 7, 2016; 22(9): 2771-2778
Published online Mar 7, 2016. doi: 10.3748/wjg.v22.i9.2771
Inhibition of SW620 human colon cancer cells by upregulating miRNA-145
Chen Li, Na Xu, Yu-Qiang Li, Yu Wang, Zhi-Tu Zhu
Chen Li, Yu-Qiang Li, Yu Wang, Biobank, The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001, Liaoning Province, China
Na Xu, Department of Radiology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001, Liaoning Province, China
Zhi-Tu Zhu, Department of Oncology, The First Affiliated Hospital of Liaoning Medical University, Jinzhou 121001, Liaoning Province, China
Author contributions: Li C and Xu N contributed equally to this work; Li C, Xu N, Li YQ, Wang Y and Zhu ZT designed the research; Li C, Wang Y and Zhu ZT performed the research; Zhu ZT and Wang Y contributed new reagents/analytic tools; Li C, Wang Y and Li YQ analyzed the data; Li C, Xu N and Wang Y wrote the paper.
Supported by Liaoning Medical “Principal Fund” special fund clinical construction, No. XZJJ20130214; and Liaoning Provincial Science and Technology Department of Science and Technology Program, No. 2013225305.
Institutional review board statement: This study was approved by the Ethics Committee of the First Affiliated Hospital of Liaoning Medical University.
Institutional animal care and use committee statement: All procedures in this study involving animals met the requirements of the ethics of animal experimentation and were approved by Laboratory Animal Ethics Committee of the First Affiliated Hospital of Liaoning Medical University.
Conflict-of-interest statement: The authors have no conflict of interests to declare.
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: Zhi-Tu Zhu, MD, Department of Oncology, The First Affiliated Hospital of Liaoning Medical University, No. 2, Wuduan, Renmin Street, Jinzhou 121001, Liaoning Province, China. zhuzhitu2014jz@hotmail.com
Telephone: +86-416-4605040 Fax: +86-416-4605067
Received: April 23, 2015
Peer-review started: April 24, 2015
First decision: July 10, 2015
Revised: August 31, 2015
Accepted: December 1, 2015
Article in press: December 1, 2015
Published online: March 7, 2016
Abstract

AIM: To investigate the targeted inhibition of proliferation and migration of SW620 human colon cancer cells by upregulating miRNA-145 (miR-145).

METHODS: Forty-five samples of colon cancer tissues and 45 normal control samples were obtained from the biological database of the First Affiliated Hospital of Liaoning Medical University. We performed quantitative analysis of miR-145 and N-ras expression in tissues; reverse transcriptase polymerase chain reaction analysis of miR-145 expression in SW620 colon cancer cells and normal colonic epithelial cells; construction of miR-145 lentiviral vector and determination of miR-145 expression in SW620 cells transduced with miR-145 vector; analysis of the effect of miR-145 overexpression on SW620 cell proliferation; analysis of the effect of miR-145 overexpression on SW620 cell migration using a wound healing assay; and analysis of the effect of miR-145 on N-ras expression using Western blotting.

RESULTS: miR-145 expression was significantly downregulated in colon cancer tissues, with its expression in normal colonic tissues being 4-5-fold higher (two sample t test, P < 0.05), whereas N-ras expression showed the opposite trend. miR-145 expression in SW620 cells was downregulated, which was significantly lower compared to that in colonic epithelial cells (two sample t test, P < 0.05). miR-145 vector and control were successfully packaged; expression of miR-145 in SW620 cells transduced with miR-145 was 8.2-fold of that in control cells (two sample t test, P < 0.05). The proliferation of miR-145-transduced SW620 cells was significantly decreased compared to control cells (two sample t test, P < 0.05). At 48 h in the wound healing experiment, the migration indexes and controls were (97.27% ± 9.25%) and (70.22% ± 6.53%), respectively (two sample t test, P < 0.05). N-ras expression in miR-145-tranduced SW620 cells was significantly lower than others (one-way analysis of variance, P < 0.05).

CONCLUSION: miR-145 is important in inhibiting colon cancer cell proliferation and migration. This is a good foundation for development of colon cancer therapy by targeting tumor suppressor miR-145.

Keywords: miRNA-145, Colorectal cancer, Targeted therapy, N-ras, Lentiviral vector

Core tip: miRNA-145 (miR-145) may play an important role in inhibiting colon cancer proliferation and invasive migration. This finding lays a good foundation for further investigation of targeting miR-145 as a tumor suppressor in colon cancer treatment, and provides novel evidence for the anti-cancer effects and therapeutic potential of miR-145.