Systematic Review
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jan 26, 2019; 7(2): 171-190
Published online Jan 26, 2019. doi: 10.12998/wjcc.v7.i2.171
Clinical significance of exosomes as potential biomarkers in cancer
Chi-Hin Wong, Yang-Chao Chen
Chi-Hin Wong, Yang-Chao Chen, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
Yang-Chao Chen, Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
Author contributions: Chen YC and Wong CH wrote the paper.
Conflict-of-interest statement: All the authors declare that they have no competing interests.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
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/
Corresponding author: Yang-Chao Chen, PhD, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China. yangchaochen@cuhk.edu.hk
Telephone: +852-39431100 Fax: +852-26035123
Received: October 25, 2018
Peer-review started: October 25, 2018
First decision: November 28, 2018
Revised: December 27, 2018
Accepted: January 3, 2019
Article in press: January 3, 2019
Published online: January 26, 2019
Abstract
BACKGROUND

Exosomes are microvesicles, measuring 30-100 nm in diameter. They are widely distributed in body fluids, including blood, bile, urine and saliva. Cancer-derived exosomes carry a wide variety of DNA, RNA, proteins and lipids, and may serve as novel biomarkers in cancer.

AIM

To summarize the performance of exosomal biomarkers in cancer diagnosis and prognosis.

METHODS

Relevant publications in the literature were identified by search of the “PubMed” database up to September 11, 2018. The quality of the included studies was assessed by QUADAS-2 and REMARK. For assessment of diagnostic biomarkers, 47 biomarkers and 2240 patients from 30 studies were included.

RESULTS

Our results suggested that these exosomal biomarkers had excellent diagnostic ability in various types of cancer, with good sensitivity and specificity. For assessment of prognostic markers, 50 biomarkers and 4797 patients from 42 studies were included. We observed that exosomal biomarkers had prognostic values in overall survival, disease-free survival and recurrence-free survival.

CONCLUSION

Exosomes can function as potential biomarkers in cancer diagnosis and prognosis.

Keywords: Exosome, Biomarker, Cancer, Diagnosis, Prognosis

Core tip: Cancer-derived exosomes carry a wide variety of DNA, RNA, proteins and lipids, which may serve as novel biomarkers in cancer. The current systematic review and meta-analysis summarized the performance of exosomal biomarkers in cancer diagnosis and prognosis. We analyzed 47 diagnostic markers and 50 prognostic markers from 56 studies with various type of cancer. We found that exosomal biomarkers had both diagnostic and prognostic power in many cancers.