Glioblastoma multiforme (GBM) and the mesenchymal GBM subtype in particular are highly malignant tumors that frequently exhibit regions of severe hypoxia and necrosis. Because these features correlate with poor prognosis, we investigated microRNAs whose expression might regulate hypoxic GBM cell survival and growth. We determined that the expression of microRNA-218 (miR-218) is decreased significantly in highly necrotic mesenchymal GBM, and orthotopic tumor studies revealed that reduced miR-218 levels confer GBM resistance to chemotherapy. Importantly, miR-218 targets multiple components of receptor tyrosine kinase (RTK) signaling pathways, and miR-218 repression increases the abundance and activity of multiple RTK effectors. This elevated RTK signaling also promotes the activation of hypoxia-inducible factor (HIF), most notably HIF2α. We further show that RTK-mediated HIF2α regulation is JNK dependent, via jun proto-oncogene. Collectively, our results identify an miR-218-RTK-HIF2α signaling axis that promotes GBM cell survival and tumor angiogenesis, particularly in necrotic mesenchymal tumors.
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http://dx.doi.org/10.1073/pnas.1314341111 | DOI Listing |
J Mol Neurosci
January 2025
Department of Pediatric Neurosurgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China.
Primary brain tumors that were the most severe and aggressive were called glioblastoma multiforme (GBM). Cancers are caused in part by aberrant expression of circular RNA. Often referred to as competitive endogenous RNA (ceRNA), circRNA molecules act as "miRNA sponges" in cells by decreasing the inhibitory impact of miRNA on their target genes and hence raising the expression levels of those genes.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
Glioblastoma (GBM) is highly malignant and grows rapidly, and there is currently a lack of effective treatments. Metabolism provides the basis for the occurrence and development of GBM. Pyruvate dehydrogenase A1 (PDHA1) is a key component in both the tricarboxylic acid cycle and glycolysis, playing an important role in the metabolic processes related to cancer, but its role in GBM remains unclear.
View Article and Find Full Text PDFAttempts to activate an anti-tumor immune response in glioblastoma (GBM) have been met with many challenges due to its inherently immunosuppressive tumor microenvironment. The degree and mechanisms by which molecularly and phenotypically diverse tumor-propagating glioma stem cells (GSCs) contribute to this state are poorly defined. In this study, our multifaceted approach combining bioinformatics analyses of clinical and experimental datasets, single-cell sequencing, and molecular and pharmacologic manipulation of patient-derived cells identified GSCs expressing immunosuppressive effectors mimicking regulatory T cells (Tregs).
View Article and Find Full Text PDFBiochim Biophys Acta Gen Subj
January 2025
Institute of Digestive Disease, the Affiliated Qingyuan Hospital (Qingyuan People's Hospital), Guangzhou Medical University, Qingyuan, Guangdong 511518, PR China. Electronic address:
Three-dimensional(3D) cell culture systems provide a larger space for cell proliferation, which is crucial for simulating cellular behavior and drug responses in the tumor microenvironment. In this study, we developed a novel 3D co-culture system for cell interactions, utilizing a commercialized bioreactor-microcarrier system. Mesenchymal stem cells (MSCs) were extracted via enzymatic digestion, and markers CD105 and CD31 were identified.
View Article and Find Full Text PDFCell Rep
January 2025
The Brain Tumor Translational Laboratory, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA; University of New Mexico Comprehensive Cancer Center, Albuquerque, NM 87131, USA. Electronic address:
The sub-ventricular zone (SVZ) is the most well-characterized neurogenic area in the mammalian brain. We previously showed that in 65% of patients with glioblastoma (GBM), the SVZ is a reservoir of cancer stem-like cells that contribute to treatment resistance and the emergence of recurrence. Here, we build a single-nucleus RNA-sequencing-based microenvironment landscape of the tumor mass and the SVZ of 15 patients and two histologically normal SVZ samples as controls.
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