Table of Contents Author Guidelines Submit a Manuscript
BioMed Research International
Volume 2019, Article ID 3702783, 5 pages
https://doi.org/10.1155/2019/3702783
Research Article

Upregulated Na+/H+-Exchange Protects Human Colon Cancer Tissue against Intracellular Acidification

1Department of Biomedicine, Aarhus University, Ole Worms Allé 3, Building 1170, DK-8000 Aarhus C, Denmark
2Regional Hospital Randers, Skovlyvej 15, DK-8930 Randers, Denmark

Correspondence should be addressed to Ebbe Boedtkjer; kd.ua.demoib@be

Received 24 October 2018; Revised 3 January 2019; Accepted 17 January 2019; Published 29 January 2019

Guest Editor: Jinwei Zhang

Copyright © 2019 Ninna C. S. Voss et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Increased metabolism accelerates local acid production in cancer tissue. The mechanisms eliminating acidic waste products from human colon cancer tissue represent promising therapeutic targets for pharmacological manipulation in order to improve prognosis for the increasing number of patients with colon cancer. We sampled biopsies of human colonic adenocarcinomas and matched normal colon tissue from patients undergoing colon cancer surgery. We measured steady-state intracellular pH and rates of net acid extrusion in freshly isolated human colonic crypts based on fluorescence microscopy. Net acid extrusion was almost entirely (>95%) Na+-dependent. The capacity for net acid extrusion was increased and steady-state intracellular pH elevated around 0.5 in crypts from colon cancer tissue compared with normal colon tissue irrespective of whether they were investigated in the presence or absence of CO2/HC. The accelerated net acid extrusion from the human colon cancer tissue was sensitive to the Na+/H+-exchange inhibitor cariporide. We conclude that enhanced net acid extrusion via Na+/H+-exchange elevates intracellular pH in human colon cancer tissue.