Topic Highlight
Copyright ©2014 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 7, 2014; 20(33): 11560-11566
Published online Sep 7, 2014. doi: 10.3748/wjg.v20.i33.11560
Cellular physiological approach for treatment of gastric cancer
Atsushi Shiozaki, Daisuke Ichikawa, Eigo Otsuji, Yoshinori Marunaka
Atsushi Shiozaki, Daisuke Ichikawa, Eigo Otsuji, Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
Yoshinori Marunaka, Departments of Molecular Cell Physiology and Bio-Ionomics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
Yoshinori Marunaka, Japan Institute for Food Education and Health, St. Agnes’ University, Kyoto 602-8013, Japan
Author contributions: Shiozaki A designed the study and wrote the manuscript; Ichikawa D and Otsuji E were involved in editing the manuscript; Marunaka Y designed the study and was involved in editing the manuscript.
Correspondence to: Atsushi Shiozaki, 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
Telephone: +81-75-2515527 Fax: +81-75-2515522
Received: October 28, 2013
Revised: January 10, 2014
Accepted: April 1, 2014
Published online: September 7, 2014
Abstract

Recent studies show that ion channels/transporters play important roles in fundamental cellular functions that would be involved in the cancer process. We review the evidence for their expression and functioning in human gastric cancer (GC), and evaluate the potential of cellular physiological approach in clinical management. Various types of ion channels, such as voltage-gated K+ channels, intracellular Cl- channels and transient receptor potential channels have been found to express in GC cells and tissues, and to control cell cycles. With regard to water channels, aquaporin 3 and 5 play an important role in the progression of GC. Regulators of intracellular pH, such as anion exchanger, sodium-hydrogen exchanger, vacuolar H+-ATPases and carbonic anhydrases are also involved in tumorigenesis of GC. Their pharmacological manipulation and gene silencing affect cellular behaviours, suggesting their potential as therapeutic targets for GC. Our studies indicate the intracellular Cl- concentration could act as a mediator of cellular signaling and control cell cycle progression in GC cells. Further, we demonstrate the cytocidal effects of hypotonic shock on GC cells, and indicate that the blockade of Cl- channels/transporters enhances these effects by inhibiting regulatory volume decrease. A deeper understanding of molecular mechanisms may lead to the discovery of these cellular physiological approaches as a novel therapeutic strategy for GC.

Keywords: Gastric cancer, Ion channels, Water channels, Intracellular pH, Intracellular chloride, Osmolality

Core tip: This article aims to systematically review the current knowledge on expression and functioning of ion transporters in gastric cancer (GC). Various types of ion channels, water channels and regulators of intracellular pH have been found to express in GC, and to control tumorigenesis. Our studies indicate the intracellular Cl- concentration could control cell cycle progression in GC cells. Further, we demonstrate the cytocidal effects of hypotonic shock, and indicate that regulation of ion transport enhances these effects. A deeper understanding of molecular mechanisms may lead to the discovery of these cellular physiological approaches as a novel therapeutic strategy for GC.