Immunosuppressive Microenvironment in H3K27 Mutant Pediatric Diffuse Midline Glioma: Single-Cell and Bioinformatics Insights on CD8A, IL7R, and ICAM1

Background: Diffuse midline gliomas (DMG) pose a grave threat as a malignant tumor primarily affecting children in the pons region. These tumors exhibit a distinct and heightened resistance to therapeutic interventions, coupled with exceptionally aggressive behavior. Methods: In this study, we accessed DMG data from the Gene Expression Omnibus (GEO) database. Subsequently, we performed functional annotation and conducted pathway enrichment analysis as well as gene set enrichment analysis (GSEA). Constructing a protein-protein interaction (PPI) network, we identified pivotal hub genes. To evaluate the impact of these hub genes on immune infiltration, we employed the CIBERSORT algorithm. Furthermore, to bolster our findings, we conducted a single-cell analysis. Results: Our findings indicate the involvement of CD8A, IL7R, and ICAM1 in immune responses targeting diverse immune cell types, such as T cells, neutrophils, NK cells, dendritic cells, γδ T cells, and Macrophages M1. Additionally, the presence of immune checkpoints, including IDO1 and TIGIT, likely contributes to intratumoral immunosuppression, thereby fostering the development of an aggressive phenotype and resistance in pediatric DMG. Conclusion: In conclusion, the collective findings of our study suggest the potential role of CD8A, IL7R, and ICAM1 as innovative biomarkers for diagnosing and prognosticating pediatric DMG. Moreover, these molecules hold promise as therapeutic targets in the management of this disease. The implications of our research underscore the importance of exploring these novel avenues for improved patient outcomes.