Korean J Intern Med.  2017 Jul;32(4):589-599. 10.3904/kjim.2016.302.

The role of hypoxia on the acquisition of epithelial-mesenchymal transition and cancer stemness: a possible link to epigenetic regulation

Affiliations
  • 1Division of Pulmonology, Department of Internal Medicine, The Cancer Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea. cmcksj@catholic.ac.kr

Abstract

A hypoxic microenvironment leads to cancer progression and increases the metastatic potential of cancer cells within tumors via epithelial-mesenchymal transition (EMT) and cancer stemness acquisition. The hypoxic response pathway can occur under oxygen tensions of < 40 mmHg through hypoxia-inducible factors (HIFs), which are considered key mediators in the adaptation to hypoxia. Previous studies have shown that cellular responses to hypoxia are required for EMT and cancer stemness maintenance through HIF-1α and HIF-2α. The principal transcription factors of EMT include Twist, Snail, Slug, Sip1 (Smad interacting protein 1), and ZEB1 (zinc finger E-box-binding homeobox 1). HIFs bind to hypoxia response elements within the promoter region of these genes and also target cancer stem cell-associated genes and mediate transcriptional responses to hypoxia during stem cell differentiation. Acquisition of stemness characteristics in epithelial cells can be induced by activation of the EMT process. The mechanism of these phenotypic changes includes epigenetic alterations, such as DNA methylation, histone modification, chromatin remodeling, and microRNAs. Increased expression of EMT and pluripotent genes also play a role through demethylation of their promoters. In this review, we summarize the role of hypoxia on the acquisition of EMT and cancer stemness and the possible association with epigenetic regulation, as well as their therapeutic applications.

Keyword

Hypoxia; Epithelial-mesenchymal transition; Cancer stemness; Epigenetic regulation

MeSH Terms

Anoxia*
Chromatin Assembly and Disassembly
DNA Methylation
Epigenomics*
Epithelial Cells
Epithelial-Mesenchymal Transition*
Fingers
Gastropoda
Genes, Homeobox
Histones
MicroRNAs
Oxygen
Promoter Regions, Genetic
Response Elements
Snails
Stem Cells
Transcription Factors
Histones
MicroRNAs
Oxygen
Transcription Factors
Full Text Links
  • KJIM
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr