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Glioblastoma multiforme (GBM) is the most malignant adult brain tumor. The current adjuvant therapies for GBM are disappointing, which are based on cytotoxicity strategy. Thus, other ways should be explored to improve the curative effect. According to the strong invasive ability of GBM cells, we assume a new treatment strategy for GBM by developing a new cell trap device (CTD) with some kind of “attractive” medium loaded in it to attract and capture the tumor cells. The in vitro experiment showed that Hepatocyte Growth Factor (HGF) presented stronger chemotaxis on C6 and U87 cell line than the Epidermal Growth Factor (EGF) and Fibroblast Growth Factor (FGF). A simple in vitro CTD loaded with HGF was made and in vivo experiments results showed that HGF successfully attracted tumor cells from tumor bed in situ into the CTD. This study proposes the new strategy for GBM treatment of “attract and trap” tumor cells is proved to be feasible.

Glioblastoma multiforme (GBM) is a primary brain tumor with devastating prognosis. Although the OThe function of Down syndrome critical region protein 3 (DSCR3) on MGMT-deficient GBM was investigated in vitro and in an orthotopic brain tumor model in mice. Purification of plasma membrane proteins by membrane-cytoplasmic separation and subsequent label free-based quantitative proteomics were used to identified potential protein partners for DSCR3. Immunofluorescence was performed to show the reverse transport of solute carrier family 38 member 1 (SLC38A1) mediated by DSCR3.DSCR3 is upregulated in MGMT-deficient GBM cells during TMZ treatment. Both DSCR3 and SLC38A1 were highly expressed in recurrent GBM patients. Silencing DSCR3 or SLC38A1 expression can increase TMZ sensitivity in MGMT-deficient GBM cells. Combination of proteomics and in vitro experiments show that DSCR3 directly binds internalized SLC38A1 to mediate its sorting into recycling pathway, which maintains the abundance on plasma membrane and enhances uptake of glutamine in MGMT-deficient GBM cells.DSCR3 is a crucial regulator of acquired TMZ resistance in MGMT-deficient GBM. The DSCR3-dependent recycling of SLC38A1 maintains its abundance on plasma membrane, leading to tumor progression and acquired TMZ resistance in MGMT-deficient GBM.

The glioblastoma (GBM) recurrence rate is high, despite multimodal treatment including surgery, radiotherapy, chemotherapy, and immunotherapy. Most recurrences occur at the resection margin that is located outside the GBM contrast-enhancing region (C region) of magnetic resonance imaging. However, the nature of the GBM cells that lie outside the C region is unclear. We used single-cell RNA sequencing (scRNA-seq) to compare 12 samples taken from inside and outside the C region from four patients with GBM and identified a cluster of GBM cells outside the C region that exhibited fragmented CNVs in chromosomes such as 1, 10, 12 and 19 (herein termed CNV 4). A transcription factor–transcription cofactor interaction network was constructed to uncover the transcriptional regulatory mechanism of these CNV 4 GBM cells that had prognostic significance (p < 0.05). Furthermore, a sub-cluster of these CNV 4 GBM cells possessed stem cell-like properties and had tumorigenic potential. In parallel, we analyzed peripheral blood mononuclear cells (PBMCs) from four patients with GBM, three patients with epilepsy and three healthy volunteers by scRNA-seq. We identified a novel subtype of proliferative immune cells only in patients with GBM. Overall, our findings indicate that CNV 4 cells might contribute to GBM recurrence and proliferative circulating immune cells are specific to patients with GBM. This study sheds light on a neglected aspect of GBM, and opens new avenues to explore GBM recurrence and immunotherapy.SignificanceWe show that a subset of GBM cells outside the C region possess the properties of stem cell and tumorigenesis potential, which might be responsible for cancer recurrence. Besides, proliferative lymphocytes are specific to the PBMCs of patients with GBM, which could help to develop novel immunotherapy.

Heterogeneity is regarded as the major factor leading to the poor outcomes of glioblastoma (GBM) patients. However, conventional two-dimensional (2D) analysis methods, such as immunohistochemistry and immunofluorescence, have limited capacity to reveal GBM spatial heterogeneity. Thus, we sought to develop an effective analysis strategy to increase the understanding of GBM spatial heterogeneity. Here, 2D and three-dimensional (3D) analysis methods were compared for the examination of cell morphology, cell distribution and large intact structures, and both types of methods were employed to dissect GBM spatial heterogeneity. The results showed that 2D assays showed only cross-sections of specimens but provided a full view. To visualize intact GBM specimens in 3D without sectioning, the optical tissue clearing methods CUBIC and iDISCO+ were used to clear opaque specimens so that they would become more transparent, after which the specimens were imaged with a two-photon microscope. The 3D analysis methods showed specimens at a large spatial scale at cell-level resolution and had overwhelming advantages in comparison to the 2D methods. Furthermore, in 3D, heterogeneity in terms of cell stemness, the microvasculature, and immune cell infiltration within GBM was comprehensively observed and analysed. Overall, we propose that 2D and 3D analysis methods should be combined to provide much greater detail to increase the understanding of GBM spatial heterogeneity.

Glioblastoma (GBM) is the most malignant and aggressive glioma, which has a very poor prognosis. Temozolomide (TMZ) is still a first-line treatment, but resistance is inevitable even in MGMT-deficient glioblastoma cells. The aims of this study were to comprehend the effect of TMZ on nucleus and the underlying mechanism of acquired TMZ resistance in MGMT-deficient GBM. We show the changes of nuclear proteome in the MGMT-deficient GBM U87 cells treated with TMZ for 1 week. Label-free-based quantitative proteomics were used to investigate nuclear protein abundance change. Subsequently, gene ontology function annotation, KEGG pathway analysis, protein-protein interaction (PPI) network construction analysis of DAPs, and immunofluorescence were applied to validate the quality of proteomics. In total, 457 (455 gene products) significant DAPs were identified, of which 327 were up-regulated and 128 were down-regulated. Bioinformatics analysis uncovered RAD50, MRE11, UBR5, MSH2, MSH6, DDB1, DDB2, RPA1, RBX1, CUL4A, and CUL4B mainly enriched in DNA damage repair related pathway and constituted a protein-protein interaction network. Ribosomal proteins were down-regulated. Cells were in a stress-responsive state, while the entire metabolic level was lowered. SIGNIFICANCE OF THE STUDY: In U87 cell treated with TMZ for 1 week, which resulted in DNA damage, we found various proteins dysregulated in the nucleus. Some proteins related to the DNA damage repair pathway were up-regulated, and there was a strong interaction. We believe this is the potential clues of chemotherapy resistance in tumour cells. These proteins can be used as indicators of tumour resistance screening in the future.

Coal gangue is a common solid waste in coal mining area, which causes great environmental pollution. Using coal gangue as filling material of highway subgrade can turn waste into treasure. In order to study the greening situation of the road section with coal gangue instead of soil as subgrade filling material, the pH and electrical conductivity (EC) were studied, The electrical conductivity (EC) and pH value of coal gangue used in a highway subgrade test section under different soaking time and initial pH solution were measured, and their change characteristics were analyzed. Both of them increased with the extension of time, and the change trend of EC was more severe. The results of correlation analysis showed that pH and EC were highly positively correlated, and the correlation coefficients were 0.7941, 0.8198 and 0.8639 at initial ph4.1, 5.2 and 6.5, respectively. On the whole, pH is proportional to EC. By mastering the change characteristics and correlation between pH and conductivity of coal gangue under different pH conditions, it can provide certain data and theoretical support for the greening research of coal gangue as subgrade filler.

The contact resistance between the bipolar plate (BPP) and the gas diffusion layer (GDL) is an important factor contributing to the power loss in proton exchange membrane (PEM) fuel cells. At present there is still not a well-developed method to estimate such contact resistance. This paper proposes two effective methods for estimating the contact resistance between the BPP and the GDL based on an experimental contact resistance–pressure constitutive relation. The constitutive relation was obtained by experimentally measuring the contact resistance between the GDL and a flat plate of the same material and processing conditions as the BPP under stated contact pressure. In the first method, which was a simplified prediction, the contact area and contact pressure between the BPP and the GDL were analyzed with a simple geometrical relation and the contact resistance was obtained by the contact resistance–pressure constitutive relation. In the second method, the contact area and contact pressure between the BPP and GDL were analyzed using FEM and the contact resistance was computed for each contact element according to the constitutive relation. The total contact resistance was then calculated by considering all contact elements in parallel. The influence of load distribution on contact resistance was also investigated. Good agreement was demonstrated between experimental results and predictions by both methods. The simplified prediction method provides an efficient approach to estimating the contact resistance in PEM fuel cells. The proposed methods for estimating the contact resistance can be useful in modeling and optimizing the assembly process to improve the performance of PEM fuel cells.