The Role of ICAM-1 on Immune Cells in Glioblastoma: A Literature Review

Abstract

Introduction: Glioblastoma (GBM) is an extremely aggressive brain tumor that poses significant challenges to clinical oncology. Previous research has discovered that intercellular adhesion molecule-1 (ICAM-1) is expressed in immune cells and is one of the most common molecules in the tumor microenvironment. However, the entire scope of ICAM-1 functions on immune cells in glioblastoma is still under investigation. This literature review aims to synthesize existing knowledge about the role of ICAM-1 on immune cells in GBM progression.

Methods: This review summarizes research from 1980-2024 using PubMed, OVID Medline, Web of Science, and Google Scholar. The following keywords were used to identify the articles focusing on the role of ICAM-1 on immune cells in glioblastoma: “glioblastoma”, “ICAM-1”, “CD54”, “macrophages”, “lymphocytes”, “dendritic cells”, and “natural killer cells”. Studies that primarily focus on ICAM-1 expression and function within the tumor microenvironment were selected.

Results: Immune cell expression of ICAM-1 in the GBM microenvironment may exhibit both pro- and anti-tumor effects. In tumor-associated macrophages, ICAM-1 upregulation regulates polarization and immunosuppression. In dendritic cells, decreased ICAM-1 expression may hinder anti-tumor responses by limiting T cell activation. The role of ICAM-1 in tumor-infiltrating lymphocytes remains unclear. In neutrophils, ICAM-1 upregulation may promote immune suppression by reducing T-cell activity. The decreased ICAM-1 levels on NK cells in GBM may lead to NK cell exhaustion.

Discussion: The radio-chemotherapy has differential effects on ICAM-1 functions and, to some extent, affects the interpretation of findings. In turn, the alteration of ICAM-1 expression also influences the effectiveness of GBM radio-chemotherapy and the composition of the tumor microenvironment. The corticosteroid administration and tumor types are also factors affecting immune cell activity and composition.

Conclusion: This review inspires innovative therapeutic strategies to improve treatment outcomes and patient prognosis for glioblastoma, as well as provides potential directions for future research on ICAM-1 for glioblastoma.