Basic Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 28, 2022; 28(32): 4649-4667
Published online Aug 28, 2022. doi: 10.3748/wjg.v28.i32.4649
Anoctamin 5 regulates the cell cycle and affects prognosis in gastric cancer
Tomoyuki Fukami, Atsushi Shiozaki, Toshiyuki Kosuga, Michihiro Kudou, Hiroki Shimizu, Takuma Ohashi, Tomohiro Arita, Hirotaka Konishi, Shuhei Komatsu, Takeshi Kubota, Hitoshi Fujiwara, Kazuma Okamoto, Mitsuo Kishimoto, Yukiko Morinaga, Eiichi Konishi, Eigo Otsuji
Tomoyuki Fukami, Atsushi Shiozaki, Toshiyuki Kosuga, Michihiro Kudou, Hiroki Shimizu, Takuma Ohashi, Tomohiro Arita, Hirotaka Konishi, Shuhei Komatsu, Takeshi Kubota, Hitoshi Fujiwara, Kazuma Okamoto, Eigo Otsuji, Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
Mitsuo Kishimoto, Department of Pathology, Kyoto City Hospital, Kyoto 604-8845, Japan
Yukiko Morinaga, Eiichi Konishi, Department of Pathology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
Author contributions: Fukami T and Shiozaki A contributed equally to this work; All authors read and approved the final manuscript and agreed to be accountable for all aspects of the report.
Supported by Japan Society for the Promotion of Science, No. 21K08689, No. 21K16456, No. 20K09016, No. 20K09084, No. 19K09202 and No. 19K09182.
Institutional review board statement: The study was reviewed and approved by the Kyoto Prefectural University of Medicine Institutional Review Board, No. ERB-C-1195.
Informed consent statement: Informed consent to be included in the study, or the equivalent, was obtained from all patients.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at shiozaki@koto.kpu-m.ac.jp. Participants gave informed consent for data sharing.
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Atsushi Shiozaki, MD, PhD, Assistant Professor, Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566, Japan. shiozaki@koto.kpu-m.ac.jp
Received: February 28, 2022
Peer-review started: February 28, 2022
First decision: May 9, 2022
Revised: June 10, 2022
Accepted: July 27, 2022
Article in press: July 27, 2022
Published online: August 28, 2022
Processing time: 178 Days and 9.5 Hours
Abstract
BACKGROUND

Anoctamin 5 (ANO5)/transmembrane protein 16E belongs to the ANO/ transmembrane protein 16 anion channel family. ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types. Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types. However, it remains unclear whether ANO5 acts as a plasma membrane chloride channel, and its expression and functions in gastric cancer (GC) have not been investigated.

AIM

To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC.

METHODS

Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines, and changes in cell proliferation, cell cycle progression, apoptosis, and cellular movement were assessed. The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis. Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department.

RESULTS

Reverse transcription-quantitative polymerase chain reaction (PCR) and western blotting demonstrated high ANO5 mRNA and protein expression, respectively, in NUGC4 and MKN45 cells. In these cells, ANO5 silencing inhibited cell proliferation and induced apoptosis. In addition, the knockdown of ANO5 inhibited G1-S phase progression, invasion, and migration. The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes, such as CDKN1A, CDK2/4/6, CCNE2, and E2F1, in ANO5-depleted NUGC4 cells. The expression of these genes was verified using reverse transcription-quantitative PCR. Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis. Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC (P = 0.0457).

CONCLUSION

ANO5 regulates the cell cycle progression by regulating the expression of cyclin-associated genes and affects the prognosis of patients with GC. These results may provide insights into the role of ANO5 as a key mediator in tumor progression and/or promising prognostic biomarker for GC.

Keywords: Anoctamin 5; Gastric cancer; Cell cycle; G1/S checkpoint; Cell proliferation

Core Tip: The present study aimed to investigate the role of anoctamin 5 (ANO5) in the regulation of tumor progression and the clinicopathological significance of its expression in gastric cancer. Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis in patients with gastric cancer. Microarray analysis results suggest that ANO5 regulates cell cycle progression by regulating the expression of cyclin-associated genes. Our results provide insights into the role of ANO5 as a mediator of and/or biomarker for gastric cancer.