外泌体（EXO）在细胞间通讯和神经胶质瘤微环境调节中发挥着至关重要的作用。肿瘤相关巨噬细胞在免疫抑制微环境中更有可能成为M2样型巨噬细胞。在这里，我们的目的是研究缺氧胶质瘤来源的外泌体介导M2样巨噬细胞极化的影响和分子机制。通过microRNA测序鉴定与常氧条件相比，缺氧条件下培养的胶质瘤细胞来源的外泌体中高表达的miRNA。使用 qRT-PCR、蛋白质印迹、流式细胞术和免疫组织化学测定巨噬细胞的极化状态。通过使用RNA-seq，我们的目的是鉴定巨噬细胞中miR-25-3p调控的下游靶基因，并研究其发挥作用的机制途径。通过EdU、Transwell实验和体内实验评估神经胶质瘤细胞的增殖和迁移能力。我们发现缺氧神经胶质瘤细胞来源的外泌体中miR-25-3p上调，并且可以转移到巨噬细胞。在巨噬细胞中，miR-25-3p下调PHLPP2的表达，从而激活PI3K-AKT-mTOR信号通路，最终导致巨噬细胞M2极化。作为反馈环路的一部分，M2极化的巨噬细胞反过来可以促进恶性胶质瘤的进展。我们的研究表明，来自缺氧胶质瘤细胞的miR-25-3p通过外泌体作为介质传递到巨噬细胞，通过以下方式促进巨噬细胞的M2极化： miR-25-3p/PHLPP2/PI3K-AKT 信号通路。这项研究表明，调节 miR-25-3p 表达、传输或抑制 PI3K-AKT 通路激活的靶向干预措施可以破坏免疫抑制微环境，为胶质瘤免疫治疗提供一种新方法。© 2024。 。

Exosomes (EXO) play crucial roles in intercellular communication and glioma microenvironment modulation. Tumor-associated macrophages are more likely to become M2-like type macrophages in the immunosuppressive microenvironment. Here, we aimed to investigate the effects and molecular mechanisms of hypoxic glioma-derived exosomes mediated M2-like macrophage polarization.Highly expressed miRNAs in exosomes derived from glioma cells cultured under hypoxia condition compared to normoxic condition were identified through microRNA sequencing. The polarization status of macrophages was determined using qRT-PCR, Western blotting, flow cytometry, and immunohistochemistry. By using RNA-seq, we aimed to identify the downstream target genes regulated by miR-25-3p in macrophages and investigate the mechanistic pathways through which it exerts its effects. The proliferation and migration capabilities of glioma cells were assessed through EdU, Transwell assays, and in vivo experiments.We found that miR-25-3p was upregulated in the exosomes derived from hypoxic glioma cells and can be transferred to the macrophage. In macrophages, miR-25-3p downregulates the expression of PHLPP2, thereby activating the PI3K-AKT-mTOR signaling pathway, ultimately leading to macrophage M2 polarization. As part of a feedback loop, M2-polarized macrophages can, in turn, promote malignant glioma progression.Our study reveals that miR-25-3p from hypoxic glioma cells is delivered to macrophages via exosomes as a mediator, promoting M2 polarization of macrophages through the miR-25-3p/PHLPP2/PI3K-AKT signaling pathway. This study suggests that targeted interventions to modulate miR-25-3p expression, transmission, or inhibition of PI3K-AKT pathway activation can disrupt the immune-suppressive microenvironment, providing a novel approach for immunotherapy in gliomas.© 2024. The Author(s).