Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jul 15, 2021; 13(7): 638-661
Published online Jul 15, 2021. doi: 10.4251/wjgo.v13.i7.638
Systems-level biomarkers identification and drug repositioning in colorectal cancer
Hande Beklen, Esra Yildirim, Medi Kori, Beste Turanli, Kazim Yalcin Arga
Hande Beklen, Esra Yildirim, Medi Kori, Beste Turanli, Kazim Yalcin Arga, Department of Bioengineering, Marmara University, Istanbul 34722, Turkey
Author contributions: Beklen H, Yildirim E, Kori M, Turanli B, Arga KY wrote, revised, and finalized the manuscript and contributed equally.
Supported by TUBITAK (Hande Beklen and Kazim Yalcin Arga), No. 119S174; Marmara University Research Fund (BAPKO), No. FEN-C-YLP-120619-0199.
Conflict-of-interest statement: The authors declare no conflict of interests for this article.
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:
Corresponding author: Kazim Yalcin Arga, PhD, Professor, Department of Bioengineering, Marmara University, Goztepe, Istanbul 34722, Turkey.
Received: March 6, 2021
Peer-review started: March 6, 2021
First decision: April 19, 2021
Revised: April 20, 2021
Accepted: May 25, 2021
Article in press: May 25, 2021
Published online: July 15, 2021

Colorectal cancer (CRC) is the most commonly diagnosed fatal cancer in both women and men worldwide. CRC ranked second in mortality and third in incidence in 2020. It is difficult to diagnose CRC at an early stage as there are no clinical symptoms. Despite advances in molecular biology, only a limited number of biomarkers have been translated into routine clinical practice to predict risk, prognosis and response to treatment. In the last decades, systems biology approaches at the omics level have gained importance. Over the years, several biomarkers for CRC have been discovered in terms of disease diagnosis and prognosis. On the other hand, a few drugs are being developed and used in clinics for the treatment of CRC. However, the development of new drugs is very costly and time-consuming as the research and development takes about 10 years and more than $1 billion. Therefore, drug repositioning (DR) could save time and money by establishing new indications for existing drugs. In this review, we aim to provide an overview of biomarkers for the diagnosis and prognosis of CRC from the systems biology perspective and insights into DR approaches for the prevention or treatment of CRC.

Keywords: Colorectal cancer, Colon cancer, Systems biology, Biomarker, Drug repositioning, Omics

Core Tip: Colorectal cancer (CRC) is the most commonly diagnosed cancer in women and men worldwide. Due to the lack of clinical symptoms, it is difficult to diagnose CRC in the early stages. There is an urgent need for alternative, inexpensive and easy-to-measure methods for screening and therapy. Systems biology and drug repositioning (DR) approaches are being used to discover biomarkers and novel targets as well as, existing drugs with different indications to develop new therapeutics and treatment strategies. Our goal was to provide an overview of systems-level biomarkers and insights into DR strategies for the treatment of CRC.