Systematic Reviews
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Methodol. Sep 20, 2022; 12(5): 428-437
Published online Sep 20, 2022. doi: 10.5662/wjm.v12.i5.428
Role of the circulatory interleukin-6 in the pathogenesis of gliomas: A systematic review
Manish Singh, Alok Raghav, Kirti Amresh Gautam
Manish Singh, Alok Raghav, Department of Neurosurgery, GSVM Medical College, Kanpur 208001, India
Kirti Amresh Gautam, Department of Basic and Applied Science, GD Goenka University, Gurugram 122103, Haryana, India
Author contributions: Singh M conceptualized this manuscript; Gautam KG and Raghav A performed the literature search and scrutiny of eligible studies; Gautam KG and Raghav A wrote the manuscript; all authors have read and approved the final draft of the manuscript.
Conflict-of-interest statement: All authors report no relevant conflict of interest for this article.
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 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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Kirti Amresh Gautam, BSc, MSc, PhD, Assistant Professor, Department of Basic and Applied Science, GD Goenka University, Sohna Road, Gurugram 122103, Haryana, India. emails2kirti@gmail.com
Received: December 13, 2021
Peer-review started: December 13, 2021
First decision: March 24, 2022
Revised: April 1, 2022
Accepted: July 24, 2022
Article in press: July 24, 2022
Published online: September 20, 2022
Processing time: 277 Days and 4.2 Hours
ARTICLE HIGHLIGHTS
Research background

Interleukin (IL)-6 is a proinflammatory cytokine that is involved in immunity, inflammation, angiogenesis, neural development and reproduction. The tumor microenvironment containing tumor cells, tumor-infiltrating immune cells and fibroblast stromal cells releases IL-6. IL-6 acts on the Janus kinase and signal transducer and activator of transcription factor pathway. These pathways release or associate with proteins that are responsible for major cellular functions.

Research motivation

This systematic review was motivated by a number of research studies that investigated the association between IL-6 and glioma.

Research objectives

In this systematic-review, case-control studies investigating the role of IL-6 with glioma development and progression have been discussed to review the utility of IL-6 as a biomarker.

Research methods

Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines were applied to filter the relevant studies based on inclusion and exclusion criteria. We used a combination of keywords and Reference Citation Analysis (RCA) tool to search for potential studies and performed data extraction from selected studies.

Research results

Five case–control studies were included for full evaluation. Most studies found a significantly higher level of IL-6 in cases as compared to controls although a study with contradictory results and a study with no difference in IL-6 level was also observed. Il-6 level varies with glioma stage, and some studies have reported lower levels in high-stage of cancer, whereas others have reported higher levels of IL-6 in early-stage glioma. Age at the time of diagnosis of glioma and IL-6 level could also have a significant relationship with glioma.

Research conclusions

IL-6 could be a potential biomarker for the diagnosis and prognosis of glioma as it was increased twofold in cases of glioma as compared to controls.

Research perspectives

Immunotherapy based treatment can be implemented by trigging IL-6 protein associated pathways and re-sensitizing the immune response to inhibit tumor growth and enhance survival rate.