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Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Apr 15, 2017; 9(4): 142-152
Published online Apr 15, 2017. doi: 10.4251/wjgo.v9.i4.142
Abnormal DNA methylation as a cell-free circulating DNA biomarker for colorectal cancer detection: A review of literature
Michail Galanopoulos, Nikolaos Tsoukalas, Ioannis S Papanikolaou, Maria Tolia, Maria Gazouli, Gerassimos J Mantzaris
Michail Galanopoulos, Gerassimos J Mantzaris, Department of Gastroenterology, “Evaggelismos-Ophthalmiatreion Athinon-Polycliniki”, GR 10676 Athens, Greece
Nikolaos Tsoukalas, Department of Medical Oncology, Veterans Hospital (417 NIMTS), GR 11524 Athens, Greece
Ioannis S Papanikolaou, Hepatogastroenterology Unit, Second Department of Internal Medicine and Research Institute, Attikon University General Hospital, Medical School, National and Kapodistrian University of Athens, GR 12461 Athens, Greece
Maria Tolia, Department of Radiotherapy/Radiation Oncology, Faculty of Medicine, School of Health Sciences, University of Thessaly, GR 41110 Larissa, Greece
Maria Gazouli, Department of Basic Medical Sciences, Laboratory of Biology Medical School, National and Kapodistrian University of Athens, GR 11527 Athens, Greece
Author contributions: Galanopoulos M and Tsoukalas N contributed equally to this work; all authors contributed to this paper with conception and design of the study, literature review and analysis, drafting and critical revision and editing, and final approval of the final version.
Conflict-of-interest statement: No potential conflicts of interest. No financial support. All the authors declare that they have no conflict of interest.
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: Nikolaos Tsoukalas, MD, MSc, PhD, Medical Oncologist, MSc in Bioinformatics, Department of Medical Oncology, Veterans Hospital (417 NIMTS), Gennimata N. 10-12 Ampelokipi, GR 11524 Athens, Greece. tsoukn@yahoo.gr
Telephone: +30-697-7366056 Fax: +30-210-7237578
Received: July 28, 2016
Peer-review started: August 1, 2016
First decision: December 1, 2016
Revised: December 28, 2016
Accepted: March 12, 2017
Article in press: March 14, 2017
Published online: April 15, 2017
Core Tip

Core tip: Colorectal cancer (CRC) is one of the most prevalent malignancies in the world. CRC-associated morbidity and mortality is continuously increasing, in part due to a lack of early detection. The main aim of this article is the brief description of the basic screening modalities and their efficacy for CRC detection, the process of colorectal carcinogenesis and how the molecular pathways of CRC (focusing on epigenetic modifications) influence the clinical application of new blood-based biomarkers such as circDNA. Then we will focus on the most recent findings concerning the studies on circDNA, mainly related to DNA methylation and the challenges for validation and globally implementation of this emergent technology.