Published online May 15, 2023. doi: 10.4251/wjgo.v15.i5.757
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
Processing time: 137 Days and 0.1 Hours
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.
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.