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Background Gliomas are the most frequent and aggressive malignancies of the central nervous system. Decades of molecular analyses have demonstrated that gliomas accumulate genetic alterations that culminate in enhanced activity of receptor tyrosine kinases and downstream mediators. While the genetic alterations, like gene amplification or loss, have been well characterized, little information exists about changes in the proteome of gliomas of different grades. Methods We performed unbiased quantitative proteomics of human glioma biopsies by mass spectrometry followed by bioinformatic analysis. Findings Various pathways were found to be up- or downregulated. In particular, endocytosis as pathway was affected by a vast and concomitant reduction of multiple machinery components involved in initiation, formation, and scission of endocytic carriers. Both clathrin-dependent and -independent endocytosis were changed, since not only clathrin, AP-2 adaptins, and endophilins were downregulated, but also dynamin that is shared by both pathways. The reduction of endocytic machinery components caused increased receptor cell surface levels, a prominent phenotype of defective endocytosis. Analysis of additional biopsies revealed that depletion of endocytic machinery components was a common trait of various glioma grades and subclasses. Interpretation We propose that impaired endocytosis creates a selective advantage in glioma tumor progression due to prolonged receptor tyrosine kinase signaling from the cell surface. Fund This work was supported by Grants 316030-164105 (to P. Jenö), 31003A-162643 (to M. Spiess) and PP00P3-176974 (to G. Hutter) from the Swiss National Science Foundation. Further funding was received by the Department of Surgery from the University Hospital Basel.

Increasing evidence has suggested that our view of stroke should be integrative, and thus a concept of dynamic interaction between cells belonging to the neurovascular unit, such as endothelial cells, astrocytes and neurons, is emerging. The functionality of this unit is altered by the complex series of interconnected pathophysiological processes that damage the brain tissue during this kind of attack. The new strategies target both the preservation of endothelium integrity and the deleterious effects induced by ionic imbalance, excitotoxicity, and the generation of reactive oxygen species within the neurovascular unit. Polyphenols exert numerous biological effects that might participate in the protection of the neurovascular unit, including anti-aggregatory platelet activity, antioxidant and free radical scavenging properties. Moreover, polyphenols are powerful vasodilators through the generation of NO, and can act on the expression of genes protective of the cardiovascular system. Also, polyphenols contribute to the preservation of the integrity of cells belonging to the neurovascular unit, mainly the endothelium, by acting on the signaling cascades implicated in endothelial apoptosis. All these effects of polyphenols might interfere with atherosclerotic plaque development and stability, vascular thrombosis and occlusion and therefore might explain their vascular- and neuroprotective properties. In this review, we focus on the beneficial effects of polyphenols on the complex pathophysiological events of stroke and helpful indications for the design of an effective and well-tolerated therapy will be discussed.

In this study, we investigated the in vivo effects of red wine polyphenol compounds (RWPC) in rats that were submitted to middle cerebral occlusion as an experimental model of stroke. Male Wistar rats were given RWPC [30 mg/(kg x d) dissolved in drinking water] or water for 1 wk before being subjected to transient middle cerebral artery occlusion followed by reperfusion. Sham-operated rats were subjected to transient occlusion in which the filament was not completely introduced. The release of amino acids and energy metabolites were monitored by intracerebral microdialysis. The volume of the ischemic lesion was assessed 24 h after reperfusion. Proteomic analysis of brain tissue was performed to study the effects of ischemia and RWPC on specific protein expression. Treatment with RWPC completely prevented the burst of excitatory amino acids that occurred in response to ischemia in untreated rats and significantly reduced brain infarct volumes. Rats chronically treated with RWPC, however, had lower basal concentrations of energy metabolites, including glucose and lactate in the brain parenchyma, compared with untreated rats. Chronic RWPC treatment significantly enhanced the residual cerebral blood flow during occlusion and reperfusion in rats subjected to transient occlusion compared with untreated rats. This effect resulted from arterial vasodilatation, as the internal diameters of several arteries were significantly enlarged after RWPC treatment. Proteomic studies revealed the modulation by RWPC of the expression of proteins involved in the maintenance of neuronal caliber and axon formation, in the protection against oxidative stress, and in energy metabolism. These findings provide an experimental basis for the beneficial effects of RWPC on the neurovascular unit during stroke.

Traumatic spinal cord injury (SCI) disrupts the blood-spinal cord barrier and reduces the blood supply caused by microvascular changes. Vessel regression and neovascularization have been observed in the course of secondary injury contributing to microvascular remodeling after trauma. Spatio-temporal distribution of blood vessels and modulation of gene expression of several angiogenic factors have been investigated in rats after spinal cord compression injury. Rarefaction of vessels was detectable at the injury site 2 days after SCI before they disappeared in the developing cavity after 2 and 4 weeks, whereas no changes were observed in the penumbra. Investigation of the temporal expression of angiogenic genes using quantitative RT-PCR disclosed a constant down-regulation of the vascular endothelial growth factor (VEGF), and transient decreases of angiopoietin-1 (Ang-1), platelet-derived growth factor-BB (PDGF-BB), as well as placental growth factor (PlGF), with the lowest values obtained 3 days after injury, when compared to the expression levels obtained in sham-operated rats. Hepatocyte growth factor (HGF) was the only angiogenic factor with a constant increased gene expression when compared with controls, starting at day 3 post-SCI. mRNA levels of transforming growth factor-beta 1 (TGF-β1) were elevated at every time point following SCI, whereas those encoding for the cysteine-rich protein CCN1/CYR61 were upregulated after 2 h, 6 h, and 1 week only. Our data provide an overview of the temporal modulated expression of the major angiogenic factors, hampering revascularization in the lesion during the phase of secondary injury. These findings should be considered in order to improve therapeutic interventions.

A patient-tailored, ex vivo drug response platform for glioblastoma (GBM) would facilitate therapy planning, provide insights into treatment-induced mechanisms in the immune tumor microenvironment (iTME), and enable the discovery of biomarkers of response. We cultured regionally annotated GBM explants in perfusion bioreactors to assess iTME responses to immunotherapy. Explants were treated with anti-CD47, anti–PD-1, or their combination, and analyzed by multiplexed microscopy [CO-Detection by indEXing (CODEX)], enabling the spatially resolved identification of >850,000 single cells, accompanied by explant secretome interrogation. Center and periphery explants differed in their cell type and soluble factor composition, and responses to immunotherapy. A subset of explants displayed increased interferon-γ levels, which correlated with shifts in immune cell composition within specified tissue compartments. Our study demonstrates that ex vivo immunotherapy of GBM explants enables an active antitumoral immune response within the tumor center and provides a framework for multidimensional personalized assessment of tumor response to immunotherapy.