Review
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. May 15, 2023; 15(5): 757-775
Published online May 15, 2023. doi: 10.4251/wjgo.v15.i5.757
Immuno-oncology-microbiome axis of gastrointestinal malignancy
Quan Lin, Shi-Wei Guan, Hai-Bo Yu
Quan Lin, Shi-Wei Guan, Hai-Bo Yu, Department of Surgery, Wenzhou Central Hospital, The Dingli Clinical Institute of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
Author contributions: All authors contributed to the original ideas and writing of this paper; Lin Q and Guan SW wrote the paper; Lin Q draw figures; Yu HB made critical revisions of this paper.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest 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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Hai-Bo Yu, MD, Chief Doctor, Department of Surgery, Wenzhou Central Hospital, The Dingli Clinical Institute of Wenzhou Medical University, No. 252 Baili East Road, Wenzhou 325000, Zhejiang Province, China. yuhaibozjwz@163.com
Received: December 26, 2022
Peer-review started: December 26, 2022
First decision: March 13, 2023
Revised: March 15, 2023
Accepted: April 14, 2023
Article in press: April 14, 2023
Published online: May 15, 2023
Abstract

Research on the relationship between the microbiome and cancer has been controversial for centuries. Recent works have discovered that the intratumor microbiome is an important component of the tumor microenvironment (TME). Intratumor bacteria, the most studied intratumor microbiome, are mainly localized in tumor cells and immune cells. As the largest bacterial reservoir in human body, the gut microbiome may be one of the sources of the intratumor microbiome in gastrointestinal malignancies. An increasing number of studies have shown that the gut and intratumor microbiome play an important role in regulating the immune tone of tumors. Moreover, it has been recently proposed that the gut and intratumor microbiome can influence tumor progression by modulating host metabolism and the immune and immune tone of the TME, which is defined as the immuno-oncology-microbiome (IOM) axis. The proposal of the IOM axis provides a new target for the tumor microbiome and tumor immunity. This review aims to reveal the mechanism and progress of the gut and intratumor microbiome in gastrointestinal malignancies such as esophageal cancer, gastric cancer, liver cancer, colorectal cancer and pancreatic cancer by exploring the IOM axis. Providing new insights into the research related to gastrointestinal malignancies.

Keywords: Gut microbiome, Intratumor microbiome, Gastrointestinal malignancy, Tumor microenvironment, Immunity, Therapy

Core Tip: The gut and intratumor microbiome can influence tumor progression by modulating host metabolism and the immune and immune tone of the tumor microenvironment, which is defined as the immuno-oncology-microbiome (IOM) axis. The proposed the IOM axis provides a new target for tumor microbiome and tumor immunity. Current studies have shown that immunotherapy with fecal microbiota transplantation or microbial metabolism have certain effects. This review aims to explore the mechanism of the IOM axis of gastrointestinal malignancies, to reveal the mechanism and progress of gut and intratumor microbiome in gastrointestinal malignancies. Providing new insights into the research related to gastrointestinal malignancies.