Journal Article

Exploring the Emerging Role of the Gut Microbiota and Tumor Microenvironment in Cancer Immunotherapy

Huang, Riming, Ma, Yucui, Luo, Lianxiang, Li, Xiaoling, Qiu, Qin, Lin, Yuqi, Liang, Juan, Luo, Hui, Liu, Kaifeng, Huang, Yuge, Chen, Zhiyan

2021

Overview

The tumor microenvironment (TME) is a complex ecosystem, which includes many different types of cells, abnormal vascular systems, and immunosuppressive cytokines. TME serves an important function in tumor tolerance and escapes from immune surveillance leading to tumor progression. Indeed, there is increasing evidence that gut microbiome is associated with cancer in a variety of ways, as specific microbial signatures are known to promote cancer development and influence safety, tolerability, and efficacy of therapies. Studies over the past five years have shown that the composition of the intestinal microbiota has a significant impact on the efficacy of anticancer immunosurveillance, which contribute to the therapeutic activity of cancer immunotherapies based on targeting cytotoxic T lymphocyte protein 4 (CTLA-4) or programmed cell death protein 1 (PD-1)–programmed cell death 1 ligand 1 (PD-L1) axis. In this review, we mainly discuss the impact of TME on cancer and immunotherapy through immune-related mechanisms. We subsequently discuss the influence of gut microbiota and its metabolites on the host immune system and the formation of TME. In addition, this review also summarizes the latest research on the role of gut microbiota in cancer immunotherapy.

• Publisher: Frontiers Media SA,Frontiers Media S.A
• Subject: Antigens / Apoptosis / Cancer / Cancer immunotherapy / Cancer therapies / Cell death / Chemokines / CTLA-4 protein / Cytokines / Cytotoxicity / Dendritic cells / Digestive system / Drug resistance / Fibroblasts / Gastrointestinal tract / Gut microbiota / host immunity / Immune response / Immune system / Immunity (Disease) / Immunological tolerance / Immunology / Immunosurveillance / Immunotherapy / Intestinal microflora / Ligands / Liver cancer / Lymphatic system / Lymphocytes / Lymphocytes T / Metastasis / Microbiomes / Microbiota / PD-1 protein / PD-L1 protein / programmed cell death protein 1/programmed cell death 1 ligand 1 / T cell receptors / Tumor microenvironment / Tumor necrosis factor-TNF / Tumors / Vascular system