Explore the vast range of titles available.

Background Angiogenesis plays an important role in the progress of glioma. RNA-binding proteins (RBPs) and circular RNAs (circRNAs), dysregulated in various tumors, have been verified to mediate diverse biological behaviors including angiogenesis. Methods Quantitative real-time PCR (qRT-PCR) and western blot were performed to detect the expression of SRSF10, circ-ATXN1, miR-526b-3p, and MMP2/VEGFA. The potential function of SRSF10/circ-ATXN1/miR-526b-3p axis in glioma-associated endothelial cells (GECs) angiogenesis was further studied. Results SRSF10 and circ-ATXN1 were significantly upregulated in GECs compared with astrocyte-associated endothelial cells (AECs). Knockdown of SRSF10 or circ-ATXN1 significantly inhibited cell viability, migration and tube formation of GECs where knockdown of SRSF10 exerted its function by inhibiting the formation of circ-ATXN1. Moreover, the combined knockdown of SRSF10 and circ-ATXN1 significantly enhanced the inhibitory effects on cell viability, migration and tube formation of GECs, compared with knockdown of SRSF10 and circ-ATXN1, respectively. MiR-526b-3p was downregulated in GECs. Circ-ATXN1 functionally targeted miR-526b-3p in an RNA-induced silencing complex. Up-regulation of miR-526b-3p inhibited cell viability, migration and tube formation of GECs. Furthermore, miR-526b-3p affected the angiogenesis of GECs via negatively regulating the expression of MMP2/VEGFA. Conclusion SRSF10/circ-ATXN1/miR-526b-3p axis played a crucial role in regulating the angiogenesis of GECs. The above findings provided new targets for anti-angiogenic therapy in glioma.

Abstract Tumor-remodeled endothelial cells not only facilitate the formation of tumor angiogenesis but also promote tumorigenesis. In this study, we aimed to explore the interaction between glioma-associated endothelial cells (GAEs) and glioma cells. We found that different subtypes of glioma owned distinct GAE abundance. Glioma patients with high GAE abundance exhibited poor prognosis. Both the results of the bioinformatics analysis and the in vitro co-culture system assay revealed that GAE promoted glioma cell invasion. Besides, anti-vascular endothelial growth factor (VEGF) therapy partially abolished the effects of GAE on gliomas. Moreover, anti-VEGF therapy upregulated IL-2 expression in GAE, and exogenous IL-2 administration inhibits GAE-induced glioma cell invasion. Collectively, our present study provides a novel outstanding of the interaction between GAE and glioma cells.

In the past several years there has been a marked increase in our understanding of the pathophysiological hallmarks of glioblastoma development and progression, with specific respect to the contribution of the glioma tumor microenvironment to the rapid progression and treatment resistance of high-grade gliomas. Despite these strides, standard of care therapy still only targets rapidly dividing tumor cells in the glioma, and does little to curb the pro-tumorigenic functions of non-cancerous cells entrenched in the glioma microenvironment. This tumor promoting environment as well as the heterogeneity of high-grade gliomas contribute to the poor prognosis of this malignancy. The interaction of non-malignant cells in the microenvironment with the tumor cells accentuate phenotypes such as rapid proliferation or immunosuppression, so therapeutically modulating one target expressed on one cell type may be insufficient to restrain these rapidly developing neoplasias. With this in mind, identifying a target expressed on multiple cell types and understanding how it governs tumor-promoting functions in each cell type may have great utility in better managing this disease. Herein, we review the physiology and pathological effects of Neuropilin-1, a transmembrane co-receptor which mediates signal transduction pathways when associated with multiple other receptors. We discuss its effects on the properties of endothelial cells and on immune cell types within gliomas including glioma-associated macrophages, microglia, cytotoxic T cells and T regulatory cells. We also consider its effects when elaborated on the surface of tumor cells with respect to proliferation, stemness and treatment resistance, and review attempts to target Neuroplin-1 in the clinical setting.

The CHI3L1 signaling pathway significantly influences glioma angiogenesis, but its role in the tumor microenvironment (TME) remains elusive. We propose a novel CHI3L1‐associated vascular phenotype classification for glioma through integrative analyses of multiple datasets with bulk and single‐cell transcriptome, genomics, digital pathology, and clinical data. We investigated the biological characteristics, genomic alterations, therapeutic vulnerabilities, and immune profiles within these phenotypes through a comprehensive multi‐omics approach. We constructed the vascular‐related risk (VR) score based on CHI3L1‐associated vascular signatures (CAVS) identified by machine learning algorithms. Utilizing unsupervised consensus clustering, gliomas were stratified into three distinct vascular phenotypes: Cluster A, marked by high vascularization and stromal activation with a relatively low levels of tumor‐infiltrating lymphocytes (TILs); Cluster B, characterized by moderate vascularization and stromal activity, coupled with a high density of TILs; and Cluster C, defined by low vascularization and sparse immune cell infiltration. We observed that the CAVS effectively indicated glioma‐associated angiogenesis and immune suppression by single‐cell RNA‐seq analysis. Moreover, the high‐VR‐score group exhibited enhanced angiogenic activity, reduced immune response, resistance to immunotherapy, and poorer clinical outcomes. The VR score independently predicted glioma prognosis and, combined with a nomogram, provided a robust clinical decision‐making tool. Potential drug prediction based on transcription factors for high‐risk patients was also performed. Our study reveals that CHI3L1‐associated vascular phenotypes shape distinct immune landscapes in gliomas, offering insights for optimizing therapeutic strategies to improve patient outcomes. We propose a novel CHI3L1‐associated vascular phenotype classification for glioma, each characterized by unique tumor features, including immune cell infiltration, metabolic reprogramming, and genomic alterations. We identified CHI3L1‐associated vascular signatures that reflect tumor angiogenesis and immunosuppression. We devised a vascular‐related risk (VR) score, with the high‐VR‐score group exhibiting enhanced angiogenic activity, reduced immune response, immunotherapy resistance, and poorer clinical outcomes.

Tumor-associated macrophages (TAMs) represent one of the main tumor-infiltrating immune cell types and are generally categorized into either of two functionally contrasting subtypes, namely classical activated M1 macrophages and alternatively activated M2 macrophages. The former typically exerts anti-tumor functions, including directly mediate cytotoxicity and antibody-dependent cell-mediated cytotoxicity (ADCC) to kill tumor cells; the latter can promote the occurrence and metastasis of tumor cells, inhibit T cell-mediated anti-tumor immune response, promote tumor angiogenesis, and lead to tumor progression. Both M1 and M2 macrophages have high degree of plasticity and thus can be converted into each other upon tumor microenvironment changes or therapeutic interventions. As the relationship between TAMs and malignant tumors becoming clearer, TAMs have become a promising target for developing new cancer treatment. In this review, we summarize the origin and types of TAMs, TAMs interaction with tumors and tumor microenvironment, and up-to-date treatment strategies targeting TAMs.

Background IDH mutant gliomas often exhibit recurrence and progression, with the mTORC1 pathway and tumor‐associated macrophages potentially contributing to these processes. However, the precise mechanisms are not fully understood. This study seeks to investigate these relationships using proteomic, phosphoproteomic, and multi‐dimensional transcriptomic approaches. Methods This study established a matched transcriptomic, proteomic, and phosphoproteomic cohort of IDH‐mutant gliomas with recurrence and progression, incorporating multiple glioma‐related datasets. We first identified the genomic landscape of recurrent IDH‐mutant gliomas through multi‐dimensional differential enrichment, GSVA, and deconvolution analyses. Next, we explored tumor‐associated macrophage subpopulations using single‐cell sequencing in mouse models of IDH‐mutant and wild‐type gliomas, analyzing transcriptional changes via AddmodelScore and pseudotime analysis. We then identified these subpopulations in matched primary and recurrent IDH‐mutant datasets, investigating their interactions with the tumor microenvironment and performing deconvolution to explore their contribution to glioma progression. Finally, spatial transcriptomics was used to map these subpopulations to glioma tissue sections, revealing spatial co‐localization with mTORC1 and angiogenesis‐related pathways. Results Multi‐dimensional differential enrichment, GSVA, and deconvolution analyses indicated that the mTORC1 pathway and the proportion of M2 macrophages are upregulated during the recurrence and progression of IDH‐mutant gliomas. CGGA database analysis showed that mTORC1 activity is significantly higher in recurrent IDH‐mutant gliomas compared to IDH‐wildtype, with a correlation to M2 macrophage infiltration. KSEA revealed that AURKA is enriched during progression, and its inhibition reduces mTORC1 pathway activity. Single‐cell sequencing in mouse models identified a distinct glioma subpopulation with upregulated mTORC1, exhibiting both M2 macrophage and angiogenesis transcriptional features, which increased after implantation of IDH‐mutant tumor cells. Similarly, human glioma single‐cell data revealed the same subpopulation, with cell–cell communication analysis showing active VEGF signaling. Finally, spatial transcriptomics deconvolution confirmed the co‐localization of this subpopulation with mTORC1 and VEGFA in high‐grade IDH‐mutant gliomas. Conclusions Our findings suggest mTORC1 activation and Angio‐TAMs play key roles in the recurrence and progression of IDH‐mutant gliomas. mTORC1 signaling drives the polarization of Angio+TAMs in recurrent IDH‐mutant gliomas, promoting angiogenesis and immune evasion, which contributes to tumor progression and recurrence in the glioma microenvironment.

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. Currently, the standard treatment of glioblastoma includes surgery, radiotherapy, and chemotherapy. Despite aggressive treatment, the median survival is only 15 months. GBM progression and therapeutic resistance are the results of the complex interactions between tumor cells and tumor microenvironment (TME). TME consists of several different cell types, such as stromal cells, endothelial cells and immune cells. Although GBM has the immunologically “cold” characteristic with very little lymphocyte infiltration, the TME of GBM can contain more than 30% of tumor-associated microglia and macrophages (TAMs). TAMs can release cytokines and growth factors to promote tumor proliferation, survival and metastasis progression as well as inhibit the function of immune cells. Thus, TAMs are logical therapeutic targets for GBM. In this review, we discussed the characteristics and functions of the TAMs and evaluated the state of the art of TAMs-targeting strategies in GBM. This review helps to understand how TAMs promote GBM progression and summarizes the present therapeutic interventions to target TAMs. It will possibly pave the way for new immune therapeutic avenues for GBM patients.

The microvasculature and immune cells are major components of the tumor microenvironment (TME). Hypoxia plays a pivotal role in the TME through hypoxia-inducible factor 1-alpha (HIF-1α) which upregulates vascular endothelial growth factor (VEGF). VEGF, an angiogenesis stimulator, suppresses tumor immunity by inhibiting the maturation of dendritic cells, and induces immunosuppressive cells such as regulatory T cells, tumor-associated macrophages, and myeloid-derived suppressor cells. HIF-1α directly induces immune checkpoint molecules. VEGF/VEGF receptor (VEGFR)-targeted therapy as a cancer treatment has not only anti-angiogenic effects, but also immune-supportive effects. Anti-angiogenic therapy has the potential to change the immunological “cold tumors” into the “hot tumors”. Glioblastoma (GB) is a hypervascular tumor with high VEGF expression which leads to development of an immuno suppressive TME. Therefore, in the last decade, several combination immunotherapies with anti-angiogenic agents have been developed for numerous tumors including GBs. In particular, combination therapy with an immune checkpoint inhibitor and VEGF/VEGFR-targeted therapy has been suggested as a synergic treatment strategy that may show favorable changes in the TME. In this article, we discuss the cross talk among immunosuppressive cells exposed to VEGF in the hypoxic TME of GBs. Current efficient combination strategies using VEGF/VEGFR-targeted therapy are reviewed and proposed as novel cancer treatments.

Glioblastoma (GBM) involves disruptions in the blood–brain barrier (BBB) and alterations in the immune microenvironment, including the activation of glioma‐associated macrophages (GAMs). Vascular endothelial growth factor inhibitors, commonly used in recurrent GBM treatment, can influence these processes. This study investigates the relationship between BBB disruption and GAM activation, focusing on plasmalemma vesicle‐associated protein (PLVAP), a marker of BBB disruption, and α1‐acid glycoprotein (AGP), an inflammatory protein implicated in tumor progression. PLVAP expression was analyzed by immunohistochemistry (IHC) in human GBM samples to determine correlations with tumor grade, proliferation, and GAM activation. Pre‐ and post‐bevacizumab treatment GBM samples were compared to assess changes in BBB integrity and macrophage activity. AGP's role in GAM activation was studied through in vitro assays and glioma implantation in AGP knockout mice, with assessments of tumor growth and angiogenesis. Results showed elevated PLVAP expression in higher‐grade gliomas, correlating with increased tumor proliferation and GAM activation, particularly around PLVAP‐positive vessels. Bevacizumab treatment reduced PLVAP expression and macrophage activity. AGP localized to regions of BBB disruption, promoting macrophage‐mediated tumor growth in vitro. AGP knockout mice demonstrated reduced angiogenesis and prolonged survival. Spatial analysis revealed increased expression of macrophage‐inducing molecules near PLVAP‐positive vessels. These findings suggest PLVAP as a marker of BBB disruption and glioma malignancy. AGP, associated with BBB leakage, contributes to GAM activation and tumor progression, highlighting its potential as a therapeutic target for GBM. Plasmalemma vesicle‐associated protein (PLVAP) is a marker of BBB disruption and correlates with GBM malignancy and tumor progression. Bevacizumab treatment potentially suppressed protumor activation of macrophages and improve the GBM microenvironment. AGP leakage was shown in BBB disrupted area, and potentially induced protumor activation of macrophages which were associated to tumor growth and angiogenesis.

Verteporfin (VP), a light-activated drug used in photodynamic therapy for the treatment of choroidal neovascular membranes, has also been shown to be an effective inhibitor of malignant cells. Recently, studies have demonstrated that, even without photo-activation, VP may still inhibit certain tumor cell lines, including ovarian cancer, hepatocarcinoma and retinoblastoma, through the inhibition of the YAP-TEAD complex. In this study, we examined the effects of VP without light activation on human glioma cell lines (LN229 and SNB19). Through western blot analysis, we identified that human glioma cells that were exposed to VP without light activation demonstrated a downregulation of YAP-TEAD-associated downstream signaling molecules, including c-myc, axl, CTGF, cyr61 and survivin and upregulation of the tumor growth inhibitor molecule p38 MAPK. In addition, we observed that expression of VEGFA and the pluripotent marker Oct-4 were also decreased. Verteporfin did not alter the Akt survival pathway or the mTor pathway but there was a modest increase in LC3-IIB, a marker of autophagosome biogenesis. This study suggests that verteporfin should be further explored as an adjuvant therapy for the treatment of glioblastoma.