1. Immunomodulatory role of exosome-derived content in pediatric medulloblastoma: a molecular subgroup perspective.
- Author
-
de Santis JO, de Sousa GR, Queiroz RGP, Cândido MF, Almeida F, de Rezende CP, de Ruy PC, Arini GS, Coyle B, Wade P, Brassesco MS, Scrideli CA, Tone LG, and Valera ET
- Subjects
- Immunomodulation, Humans, Child, Cell Line, Tumor, Medulloblastoma immunology, Medulloblastoma secondary, Cerebellar Neoplasms immunology, Cerebellar Neoplasms pathology, Exosomes immunology, Tumor-Associated Macrophages immunology
- Abstract
Medulloblastoma (MB) is the most common malignant brain tumor in children, comprising four distinct subgroups: wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4. MYC amplification and metastatic dissemination are challenges in clinical management, and tumor-associated macrophages (TAMs) play an essential role in these intricate molecular processes. However, the influence of immune cells in MB metastasis and MYC-amp is unclear. Secretion of extracellular vesicles (EVs) has emerged as a pivotal mediator facilitating communication within the tumor microenvironment, orchestrating coordinated responses among immune cells during tumor initiation, progression, and tumor dissemination. Here, we sought to elucidate the role of exosome-derived MBs in promoting specific patterns of TAM polarization across different molecular subgroups of MB cell lines. CIBERSORTx analysis using a single-cell RNA dataset revealed an increase in M0 macrophages and a decreased proportion of M2 macrophages in MB patients with tumor dissemination in the central nervous system (CNS). Cell-derived exosomes were found to secrete high levels of IL-4, IL-10, and TGF-β, indicative of a protumor M2-profile pattern. Moreover, EVs from SHH TP53-mutated, Group 3/4, and MYC-amplified MBs induced dissimilar patterns of TNF-α and/or IL-1β overexpression. This study demonstrates that exosomes from pediatric MBs promote a predominant M2-macrophage phenotype and Group 3, Group 4, SHH TP53-mutated, and MYC-amplified MBs induced a mixed M1/M2 response pattern. These findings shed light on the pivotal role of exosomes in modulating the immune response, potentially contributing to immune escape in this malignant neoplasm., Competing Interests: Declarations. Conflict of interest: The authors declare that they have no competing interests. Ethical approval: The study was conducted in accordance with the CEUA of the Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil (CEUA-FMRP, Protocol number: 2.101.529)., (© 2025. The Author(s) under exclusive licence to Japan Human Cell Society.)
- Published
- 2025
- Full Text
- View/download PDF