Glioblastoma Multiforme Progression Research Articles

BCAS3 accelerates glioblastoma tumorigenesis by restraining the P53/GADD45α signaling pathway

As in many other cancers, highly malignant proliferation and disordered cell division play irreplaceable roles in the exceedingly easy recurrence and complex progression of glioblastoma multiforme (GBM); however, mechanistic studies of the numerous regulators involved in this process are still insufficiently thorough. The role of BCAS3 has been studied in other cancers, but its role in GBM is unclear. Here, our goal was to investigate the expression pattern of BCAS3 in GBM and its potential mechanism of action. Using TCGA database and human GBM samples, we found that BCAS3 expression was up-regulated in GBM, and its high expression predicted poor prognosis. To further investigate the relationship between BCAS3 and GBM characteristics, we up-regulated and down-regulated BCAS3 expression in GBM to detect its effect on cell proliferation and cell cycle. At the same time, we established U87 cells stably overexpressing BCAS3 and generated an intracranial xenograft model to investigate the Potential role of BCAS3 in vivo. Finally, based on in vitro cell experiments and in vivo GBM xenograft models, we observed that BCAS3 significantly regulates GBM cell proliferation and cell cycle and that this regulation is associated with p53/GADD45α Signaling pathway. Taken together, our findings suggest that BCAS3 is inextricably linked to the progression of GBM and that targeting BCAS3 may have therapeutic effects in GBM patients.

FGL2 expression and relation with survival and prognosis in patients treated with concurrent temozolamide and radiotherapy in high-grade glioma.

e14019 Background: FGL2 is a member of the fibrinogen-related protein, Literature suggests that FGL2 contributes to the progression of glioblastoma multiforme (GBM) through inducing multiple immunosuppression mechanisms. The present study aimed at evaluation of the expression and the prognostic value of FGL2 in high grade glioma. Methods: In our study, we analysed sixty specimens retrieved at diagnosis of high grade glioma patients. They received concurrent Temozolamide and radiotherapy, as a standard of care, during the period from October 2019 to December 2020 and and were followed up for 12 months . Evaluation of FGL2 expression done by using FGL2 Immunohistochemistry .ClinicalTrials.gov Identifier: NCT04113278. Results: Mean age of studied patients was (48.88± 12.45) . Majority (75%) of patients were males. Mean FGL2 expression was 61 ± 31.80 (%) with range between 3% and 95%. It was found that 7 (11.7%) patients had negative FGL2. Over the period of follow up, incidence of disease progression was significantly higher among the patients with higher percentage of FGL2 in comparison to those with lower FGL2 percentages (76.54 ± 18.52 vs. 56.17 ± 33.41(%); P= 0.04). number of deaths was also significantly higher among the high FGL2 percentage group (64.86 ± 31.58 vs. 54.16 ± 31.71(%); P= 0.03). Intensity of FGL2 was mild 16 (26.7%), moderate 20 (33.3%) and strong 17 (28.3%) . Intensity of FGL2 was more among patients with disease progression. All patients with progression had either moderate intensity (46.2%) or strong intensity (53.8%). Seven (14.9%) patients without disease progression had negative FGL2 expression with ( P= 0.01). Disease free progression (DFP) was significantly negatively correlated with increasing in the intensity of FGL2. Patients with strong intensity had the lowest DFP (14 month) while patients with negative FGL2 and mild intensity had the highest DFP (25 month) with ( P <0.001). Overall survival was significantly worse with increasing in the intensity of FGL2 where patients with strong intensity had the lowest overall survival (19 month), while patients with negative FGL2 and mild intensity had the highest overall survival (27and 26 month, respectively) with ( P <0.001). For prediction of progression among patients with high grade glioma, FGL2 at cut off point > 60% has 92.3% sensitivity and 28% specificity with ( P= 0.04). For prediction of mortality among patients with high grade glioma, FGL2 at cut off point > 70% has 67% sensitivity and 61% specificity with ( P= 0.03). Conclusions: FGL2 expression in high grade glioma patients can be used as a prognostic factor but additional studies are required to clarify the prognostic value.

Dematin inhibits glioblastoma malignancy through RhoA-mediated CDKs downregulation and cytoskeleton remodeling

Glioblastoma multiforme (GBM) is well known as a highly aggressive brain tumor subtype. Here, we show that overexpression (OE) of dematin actin-binding protein (DMTN) inhibits GBM proliferation and invasion by affecting cell cycle regulation and actin remodeling, respectively. RT–qPCR, western blotting, and immunohistochemical (IHC) staining demonstrated a significant reduction in DMTN expression in gliomas, especially in high-grade gliomas (HGG) compared with normal brains, which correlates with worse survival in HGG patients. Functional studies revealed inhibitory effects of DMTN on tumor proliferation and migratory capacities. The attenuation in tumor proliferative ability upon DMTN OE was accompanied by RhoA suppression and CDK1, CDK2, CDK4, and cyclin D1 downregulation, while RhoA rescue restored the proliferative phenotype. Meanwhile, overexpression of DMTN produced profoundly disorganized stress fibers, which led to impaired tumor invasion. Furthermore, DMTN overexpression produced substantial suppression of tumor growth upon subcutaneous and intracranial implantation in mice, and this was accompanied by significantly reduced vinculin expression and Ki67 positivity. Taken together, these findings demonstrate the role of DMTN in regulating GBM cell proliferation, actin cytoskeleton, and cell morphology and identify DMTN as a vital tumor suppressor in GBM progression.

LncRNA H19 promotes glioblastoma multiforme development by activating autophagy by sponging miR-491-5p

ABSTRACT Glioblastoma multiforme (GBM) is a malignant cancer with severely poor survival, and the cells continue to thrive during hypoxia and toxic stress through autophagy. To validate the oncogenic role of long noncoding RNA H19 in GBM progression and examine whether autophagy and/or miR-491-5p participate in the process. The expression of H19 and autophagy-related genes in GBM and healthy control tissues was assessed via quantitative polymerase chain reaction. In addition, cell viability, proliferation, apoptosis and autophagy were respectively determined via cell counting kit-8 assay, clone formation assay, flow cytometry, western blotting and green fluorescent protein–microtubule-associated protein 1 light chain 3 alpha fluorescence analysis in vitro. Furthermore, a rescue assay was performed using rapamycin or miR-491-5p antagomir to examine the role of autophagy or miR-491-5p in H19-mediated regulation of proliferation and apoptosis. RNA pull-down and dual-luciferase reporter assays were employed to analyze the interaction between H19 and miR-491-5p. Additionally, tumor growth in a xenograft-bearing mouse model and autophagy in tumor mass were analyzed in vivo. The expression H19 was increased in GBM and was positively correlated with LC3 or Beclin-1. Silencing H19 inhibited growth and promoted apoptosis in GBM cells both in vitro and in vivo, and miR-491-5p was identified as one of the important mediators. H19 regulated the autophagy signaling pathway at least partly via miR-491-5p. Increased H19 expression in GBM exerts oncogenic effects by sponging miR-491-5p and enhancing autophagy. Therefore, H19 may be explored as a target for GBM therapy.

CBX3 accelerates the malignant progression of glioblastoma multiforme by stabilizing EGFR expression.

CBX3, also known as HP1γ, is a major isoform of heterochromatin protein 1, whose deregulation has been reported to promote the development of human cancers. However, the molecular mechanism of CBX3 in glioblastoma multiforme (GBM) are unclear. Our study reported the identification of CBX3 as a potential therapeutic target for GBM. Briefly, we found that, CBX3 is significantly upregulated in GBM and reduces patient survival. In addition, functional assays demonstrated that CBX3 significantly promote the proliferation, invasion and tumorigenesis of GBM cells in vitro and in vivo. Mechanistically, Erlotinib, a small molecule targeting epidermal growth factor receptor (EGFR) tyrosine kinase, was used to demonstrate that CBX3 direct the malignant progression of GBM are EGFR dependent. Previous studies have shown that PARK2(Parkin) and STUB1(Carboxy Terminus of Hsp70-Interacting Protein) are EGFR-specific E3 ligases. Notably, we verified that CBX3 directly suppressed PARK2 and STUB1 at the transcriptional level through its CD domain to reduce the ubiquitination of EGFR. Moreover, the CSD domain of CBX3 interacted with PARK2 and regulated its ubiquitination to further reduce its protein level. Collectively, these results revealed an unknown mechanism underlying the pathogenesis of GBM and confirmed that CBX3 is a promising therapeutic target.

Screening the Significant Hub Genes by Comparing Tumor Cells, Normoxic and Hypoxic Glioblastoma Stem-like Cell Lines Using Co-Expression Analysis in Glioblastoma.

Glioblastoma multiforme (GBM) is categorized by rapid malignant cellular growth in the central nervous system (CNS) tumors. It is one of the most prevailing primary brain tumors, particularly in human male adults. Even though the combination therapy comprises surgery, chemotherapy, and adjuvant therapies, the survival rate is on average 14.6 months. Glioma stem cells (GSCs) have key roles in tumorigenesis, progression, and counteracting chemotherapy and radiotherapy. In our study, firstly, the gene expression dataset GSE45117 was retrieved and differentially expressed genes (DEGs) were spotted. The co-expression network analysis was employed on DEGs to find the significant modules. The most significant module resulting from co-expression analysis was the turquoise module. The turquoise module related to the tumor cells, hypoxia, normoxic treatments of glioblastoma tumor (GBT), and GSCs were screened. Sixty-one common genes in the turquoise module were selected generated through the co-expression analysis and protein–protein interaction (PPI) network. Moreover, the GO and KEGG pathway enrichment results were studied. Twenty common hub genes were screened by the NetworkAnalyst web instrument constructed on the PPI network through the STRING database. After survival analysis via the Kaplan–Meier (KM) plotter from The Cancer Genome Atlas (TCGA) database, we identified the five most significant hub genes strongly related to the progression of GBM. We further observed these five most significant hub genes also up-regulated in another GBM gene expression dataset. The protein–protein interaction (PPI) network of the turquoise module genes was constructed and a KEGG pathway enrichments study of the turquoise module genes was performed. The VEGF signaling pathway was emphasized because of the strong link with GBM. A gene–disease association network was further constructed to demonstrate the information of the progression of GBM and other related brain neoplasms. All hub genes assessed through this study would be potential markers for the prognosis and diagnosis of GBM.

Non-negative matrix factorization and differential expression analyses identify hub genes linked to progression and prognosis of glioblastoma multiforme

One of the most prevailing primary brain tumors in adult human male is glioblastoma multiforme (GBM), which is categorized by rapid cellular growth. Even though the combination therapy comprises surgery, chemotherapy, and adjuvant therapies, the survival rate, on average, is 14.6 months. Glioma stem cells (GSCs) have key roles in tumorigenesis, progression, and defiance against chemotherapy and radiotherapy. In our study, firstly, the gene expression dataset GSE124145 was retrieved; the non-negative matrix factorization (NMF) method was applied on GBM dataset, and differentially expressed genes analysis (DEGs) was performed. After which, overlapping genes between metagenes and DEGs were detected to examine the Gene Ontology (GO) categories in the biological process (BP) in the stemness of GBM. The common hub genes were used to construct protein–protein interaction (PPI) network and further GO, while Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway was utilized to pinpoint the real hub genes. The analysis of hub genes particular for the same GO categories demonstrated that specific hub genes triggered distinct features of the same biological processes. After utilizing GSE124145 and The Cancer Genome Atlas (TCGA) dataset for survival analysis, we screened five real hub genes: GUCA1A, RFC2, GNG11, MMP19, and NRG1, which are strongly associated with the progression and prognosis of GBM. The DEGs analysis revealed that all real hub genes were overexpressed in GBM and TCGA datasets, which further validates our results. The constructed study of PPI, GO, and KEGG pathway on common hub genes was performed. Finally, the KEGG pathways performed on the top 15 candidate hub genes (including six real hub genes) of the PPI network in the GBM gene expression dataset study found mitogen-activated protein kinase (Mapk) signaling pathway to be the most significant pathway. The rest of the hub genes reviewed throughout the analysis might be favorable targets for diagnosing and treating GBM and lower-grade gliomas.

Alteration of the translational readthrough isoform AQP4ex induces redistribution and downregulation of AQP4 in human glioblastoma

Glioblastoma multiforme (GBM) is characterized by a remarkable cellular and molecular heterogeneity that make the behavior of this tumor highly variable and resistant to therapy. In addition, the most serious clinical complication of GBM and other brain tumors is the development of vasogenic edema which dramatically increase the intracranial pressure. In the present study we evaluate the expression, supramolecular organization and spatial distribution of AQP4 and AQP4ex, the new readthrough isoform of AQP4, in relationship with the degree of vasogenic brain edema and tumor progression. To this purpose, tissue samples from regions of tumor core, peritumoral and non-infiltrated tissues of each GBM patient (n = 31) were analyzed. Immunofluorescence experiments revealed that the expression of AQP4ex was almost absent in tumoral regions while the canonical AQP4 isoforms appear mostly delocalized. In peritumoral tissues, AQP4 expression was found altered in those perivascular astrocyte processes where AQP4ex appeared reduced and partially delocalized. Protein expression levels measured by immunoblot showed that global AQP4 was reduced mainly in the tumor core. Notably, the relative amount of AQP4ex was more severely reduced starting from the peritumoral region. BN-PAGE experiments showed that the supramolecular organization of AQP4 is only partially affected in GBM. Edema assessment by magnetic resonance imaging revealed that the level of AQP4ex downregulation correlated with edema severity. Finally, the degree of BBB alteration, measured with sodium fluorescein content in GBM biopsies, correlated with the edema index and AQP4ex downregulation. Altogether these data suggest that the AQP4ex isoform is critical in the triggering event of progressive downregulation and mislocalization of AQP4 in GBM, which may affect the integrity of the BBB and contributes to accumulation of edema in the peritumoral tissue. Thus, AQP4ex could be considered as a potential early biomarker of GBM progression.

A Promising Glycolysis- and Immune-Related Prognostic Signature for Glioblastoma

Glioblastoma multiforme (GBM) is a malignant brain tumor with a poor prognosis. Aerobic glycolysis and an immunosuppressive microenvironment are potentially correlated with progression of GBM. However, the prognostic value of glycolysis-immune-related genes has not been studied in GBM. Using GBM-related data downloaded from Chinese Glioma Genome Atlas database, the overlapped differentially expressed genes were identified between the GBM patients with a different glycolysis status and immune score, which had also undergone functional enrichment. Univariate Cox regression analysis and LASSO (least absolute shrinkage and selection operator) Cox regression analysis were used for risk score construction. Multivariate Cox regression analysis and survival analysis determined the independent prognostic factors. We found 277 overlapped differentially expressed genes between high glycolysis and low glycolysis, a high immune score and low immune score, and a combination of low glycolysis status and a low immune score and high glycolysis status and a high immune score. These were significantly enriched in 301 gene otology terms and 25 Kyoto Encyclopedia of Genes and Genomes pathways. Of these, 8 genes were found to be optimal for building a risk score. The risk score was an independent prognostic factor for GBM patients, and patients with a high score had a worse prognosis. Moreover, between the high- and low-risk GBM patients, 17 types of immune cells were differentially infiltrated, and 5 immune checkpoints were differentially expressed. The glycolysis-immune-related risk score using CACNG2, CSMD3, GABRA3, KCNIP2, KSR2, PTPRT, TNFRSF12A, and TNR was able to predict the prognosis of GBM patients relatively reliably.

Establishment and External Validation of a Hypoxia-Derived Gene Signature for Robustly Predicting Prognosis and Therapeutic Responses in Glioblastoma Multiforme.

Objective Hypoxia presents a salient feature investigated in most solid tumors that holds key roles in cancer progression, including glioblastoma multiforme (GBM). Here, we aimed to construct a hypoxia-derived gene signature for identifying the high-risk GBM patients to guide adjuvant therapy and precision nursing based on signs of hypoxia. Methods We retrospectively analyzed the transcriptome profiling and clinicopathological characteristics of GBM from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) cohorts. A series of bioinformatic and machine learning methods were comprehensively applied for establishing a hypoxia-derived gene signature in prediction of overall survival, disease-free survival, disease-specific survival, and progression-free survival. The predictive efficacy of this model was assessed with receiver operator characteristic (ROC) and uni- and multivariate cox regression analysis. The associations of this signature with tumor microenvironment and immunotherapeutic response predictors were evaluated across GBM. RT-qPCR and western blotting were presented for validating the expression of ALDH3B1 and CTSZ in human glioma cell lines (U251, SHG-44, and U87) and normal glial cell line HEB. Results Among hallmarks of cancer, hypoxia acted as a prominent risk factor of GBM prognosis. A hypoxia-derived gene signature displayed efficient ability in predicting clinical outcomes. High risk score indicated undesirable prognosis, recurrence, and progression of GBM. Moreover, this risk score displayed positive correlations to immunity and stromal activation. Combining immunotherapeutic response predictors, high-risk patients more benefited from immunotherapy. ALDH3B1 and CTSZ expression had prominent upregulation in glioma cells than normal glial cells. Conclusion Collectively, this hypoxia-derived gene signature could become a reliable biomarker for predicting prognosis and therapeutic response and providing theoretical support for hypoxia treatment and precision nursing of GBM patients.

PRL1 Promotes Glioblastoma Invasion and Tumorigenesis via Activating USP36-Mediated Snail2 Deubiquitination.

Regenerating liver phosphatase 1 (PRL1) is an established oncogene in various cancers, although its biological function and the underlying mechanisms in glioblastoma multiforme (GBM) remain unclear. Here, we showed that PRL1 was significantly upregulated in glioma tissues and cell lines, and positively correlated with the tumor grade. Consistently, ectopic expression of PRL1 in glioma cell lines significantly enhanced their tumorigenicity and invasion both in vitro and in vivo by promoting epithelial-mesenchymal transition (EMT). Conversely, knocking down PRL1 blocked EMT in GBM cells, and inhibited their invasion, migration and tumorigenic growth. Additionally, PRL1 also stabilized Snail2 through its deubiquitination by activating USP36, thus revealing Snail2 as a crucial mediator of the oncogenic effects of PRL1 in GBM pathogenesis. Finally, PRL1 protein levels were positively correlated with that of Snail2 and predicted poor outcome of GBMs. Collectively, our data support that PRL1 promotes GBM progression by activating USP36-mediated Snail2 deubiquitination. This novel PRL1/USP36/Snail2 axis may be a promising therapeutic target for glioblastoma.

Altered Elemental Distribution in Male Rat Brain Tissue as a Predictor of Glioblastoma Multiforme Growth-Studies Using SR-XRF Microscopy.

Glioblastoma multiforme (GBM) is a particularly malignant primary brain tumor. Despite enormous advances in the surgical treatment of cancer, radio- and chemotherapy, the average survival of patients suffering from this cancer does not usually exceed several months. For obvious ethical reasons, the search and testing of the new drugs and therapies of GBM cannot be carried out on humans, and for this purpose, animal models of the disease are most often used. However, to assess the efficacy and safety of the therapy basing on these models, a deep knowledge of the pathological changes associated with tumor development in the animal brain is necessary. Therefore, as part of our study, the synchrotron radiation-based X-ray fluorescence microscopy was applied for multi-elemental micro-imaging of the rat brain in which glioblastoma develops. Elemental changes occurring in animals after the implantation of two human glioma cell lines as well as the cells taken directly from a patient suffering from GBM were compared. Both the extent and intensity of elemental changes strongly correlated with the regions of glioma growth. The obtained results showed that the observation of elemental anomalies accompanying tumor development within an animal’s brain might facilitate our understanding of the pathogenesis and progress of GBM and also determine potential biomarkers of its extension. The tumors appearing in a rat’s brain were characterized by an increased accumulation of Fe and Se, whilst the tissue directly surrounding the tumor presented a higher accumulation of Cu. Furthermore, the results of the study allow us to consider Se as a potential elemental marker of GBM progression.

IL-33 induces ADAMTS5 expression and cell migration in glioblastoma multiforme.

Glioblastoma multiforme (GBM), characterized by a high rate of proliferation and migration capacity, is an incurable brain tumor in adults. Interleukin-33 (IL-33), a member of the IL-1 cytokine superfamily, and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), a family of zinc dependent metalloproteinases, are known to have essential roles in GBM migration and invasion. Previous studies have separately revealed elevated expressions of IL-33 and ADAMTS5 in GBM; however, the interaction between IL-33 and ADAMTS5 in GBM remains unclear. Here, using publically available GlioVis and GEPIA programs, we showed that mRNA expressions of IL-33 and ADAMTS5 are significantly high in GBM cells, and a positive correlation between IL-33 and ADAMTS5 was also determined in these cells. In parallel with the mRNA data of IL-33 and ADAMTS5, by Western blot analysis, protein levels were found to be elevated in GBM tissues and increased gradually with the disease progression. Primary GBM cells and low-grade glioma cells were then treated with IL-33 to examine its stimulating effect on ADAMTS5 expression. Exposure to IL-33 raised ADAMTS5 protein levels in a dose-dependent manner. Finally, the wound-healing method was performed to confirm the impact of IL-33 on migration in primary GBM cells. IL-33 promoted migration of primary GBM cells three times higher than untreated GBM cells. Thus, the current study suggests for the first time that IL-33 might have a role in playing a part in GBM progression through induction of ADAMTS5 expression and promotion of migration in GBM cells.

Targeting the splicing factor NONO inhibits GBM progression through GPX1 intron retention.

Background: Splicing factors are essential for nascent pre-mRNA processing and critical in cancer progression, suggesting that proteins with splicing functions represent potential molecular targets for cancer therapy. Here, we investigate the role of splicing factors in glioblastoma multiforme (GBM) progression and the possibility of targeting them for the treatment of the disease.Methods: The TCGA and CGGA public databases were used to screen for differentially expressed mRNA splicing factors. Immunohistochemistry and qRT-PCR were used to analyze the expression of non-POU domain-containing octamer-binding protein (NONO), a Drosophila behavior human splicing (DBHS) protein. Knockdown/overexpression of NONO with siRNA and lentiviral expression constructs was used to examine cell growth, apoptosis, and invasion in GBM cells. RNA sequencing was used to identify potential downstream molecular targets of NONO. RIP-PCR and RNA pulldown were used to determine the interaction between NONO and pre-mRNA. JC-1 staining and the seahorse assay were performed to assess redox homeostasis.Results: Expression of NONO was increased in GBM samples and associated with poor survival in patients (P = 0.04). Knockdown of NONO suppressed GBM growth, and overexpression of NONO promoted GBM tumorigenesis in vitro and in vivo. RNA sequencing-based transcriptomic profiling confirmed that knockdown of NONO in U251 and P3 cells resulted in global intron retention of pre-mRNA and led to abnormal splicing of specific pre-mRNAs for GPX1 and CCN1. NONO bound to a consensus motif in the intron of GPX1 pre-mRNA in association with another DBHS protein family member, PSPC1. Knockdown of NONO impaired tumor growth, invasion, and redox homeostasis through aberrant splicing of GPX1. Finally, Auranofin, a small molecule inhibitor of NONO, suppressed GBM tumor growth in an orthotopic xenograft model in mice.Conclusions: We demonstrated that intron retention was a critical alternative RNA splicing event to occur in GBM progression, and that NONO was a key regulator of mRNA splicing in GBM. Targeting NONO represents a novel, potential therapeutic strategy for GBM treatment.

Single Cell RNA Analysis of Glioma Neural Stem Cells Shows Disturbed Amino Acids Metabolism and Axonal Growth Cone Dynamics in Glioblastoma Multiforme

Glioblastoma multiforme(GBM) is a group of aggressive tumors of the central nervous system. Despite advancements in the treatment of GBM, patients diagnosed with these tumors typically have a poor prognosis and poor quality of life as the disease develops. The single-cell RNA high-throughput sequencing processed data for Glioma cancer stem cells were taken from GEO and analyzed to find out the underlying expression differences at the gene level between glioma neural stem cells(GSCs) and Normal neural stem cells(NSCs). In the current study, we have performed an RNA-sequencing analysis between GSCs and NSCs to better understand the origin of GBM. We have performed bioinformatics analysis on the transcriptional profile of 134 samples which consisted of 75 GSCs and 59 NSCs obtained from the NCBI bio project(PRJNA546254). First, an exploratory analysis was performed which showed significant variation patterns between GSCs and NSCs. Subsequently, Deseq2 differential gene expression analysis identified 1436 differentially expressed genes be-tween GSCs and NSCs[(padj. value <0.05, log2 fold change (>=+/-1.5)]. This study reveals genes like MAOA, MAOB, GATM, GLDC, AMT, and SHMT1 as the key features contributing to the disturbed processes of Glycine, threonine, and serine amino acid metabolism, axonal cone growth curve, and cell migration in Glioma. Conclusively, our study also depicts gene expression changes in amyloid beta-binding protein in between GSCs and NSCs which plays an important role in tumor microenvironment formation. Besides, the results presented here reveal new insight into the progression of GBM and the identification of novel genes involved in gliomagenesis.

Tracking glioblastoma progression after initial resection with minimal reaction-diffusion models.

We describe a preliminary effort to model the growth and progression of glioblastoma multiforme, an aggressive form of primary brain cancer, in patients undergoing treatment for recurrence of tumor following initial surgery and chemoradiation. Two reaction-diffusion models are used: the Fisher-Kolmogorov equation and a 2-population model, developed by the authors, that divides the tumor into actively proliferating and quiescent (or necrotic) cells. The models are simulated on 3-dimensional brain geometries derived from magnetic resonance imaging (MRI) scans provided by the Barrow Neurological Institute. The study consists of 17 clinical time intervals across 10 patients that have been followed in detail, each of whom shows significant progression of tumor over a period of 1 to 3 months on sequential follow up scans. A Taguchi sampling design is implemented to estimate the variability of the predicted tumors to using 144 different choices of model parameters. In 9 cases, model parameters can be identified such that the simulated tumor, using both models, contains at least 40 percent of the volume of the observed tumor. We discuss some potential improvements that can be made to the parameterizations of the models and their initialization.

The Influence of Human Astrocyte-Conditioned Media on Glioblastoma Multiforme Response to Temozolomide and Bay 11-7082

Glioblastoma Multiforme (GBM) cells interact with a complex, heterogeneous tumor microenvironment (TME). This TME consists of astrocytes, endothelial cells, microglia, and pericytes, which together play a role in GBM progression and resistance. However, there are not enough in vitro three-dimensional (3D) models to study the effect of the TME on GBM resistance to chemotherapeutics. In this study, we created a GBM TME by culturing GBM cells with media that had been conditioned by human astrocytes (HA) in 3D microwells. In order to investigate the effect of the TME on GBM resistance to chemotherapeutic agents, cells were treated with Temozolomide (TMZ) in combination with nuclear factor- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\kappa \text{B}$ </tex-math></inline-formula> (NF- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\kappa \text{B}$ </tex-math></inline-formula> ) inhibitor “Bay 11-7082”. We examined the influence of HA conditioned media (CM) on the expression of various genes and the response to TMZ and Bay 11–7082 in our 3D cultures. Our data suggested that proteins and metabolic factors produced by HA in CM can significantly alter GBM response to chemotherapeutics. Our results indicated lower levels of apoptosis- and drug resistance-related genes were detected in LN229 and U87 cultures in their respective cell culture media compared to HA CM. Our results confirmed HA affect GBM response to therapy.

Identification of Prognostic Biomarkers for Glioblastoma Based on Transcriptome and Proteome Association Analysis.

Objective:Glioblastoma multiforme (GBM) is the most malignant primary brain tumor in adults. This study aimed to identify significant prognostic biomarkers related to GBM.Methods:We collected 3 GBM and 3 healthy human brain samples for transcriptome and proteomic sequencing analysis. Differentially expressed genes (DEGs) between GBM and control samples were identified using the edge R package in R. Functional enrichment analyses, prediction of long noncoding RNA target genes, and protein-protein interaction network analyses were performed. Subsequently, transcriptomic and proteomic association analyses, validation using The Cancer Genome Atlas (TCGA) database, and survival and prognostic analyses were conducted. Then the hub genes directly related to GBM were screened. Finally, the expression of key genes was verified by quantitative polymerase chain reaction (qPCR).Results:Totally, 1140 transcripts and 503 proteins were significantly up- or down-regulated. A total of 25 genes were upregulated and 62 were downregulated at both the transcriptome and proteome levels. Results from TCGA database showed that 84 of these 87 genes matched with transcriptome sequencing results. A Cox regression analysis suggested that Fibronectin 1(FN1) was a prognostic risk factor. The qPCR results showed that FN1 was significantly upregulated in GBM samples.Conclusions: FN1 may play a role in GBM progression through ECM-receptor interaction and PI3K-Akt signaling pathways. FN1 may be considered as a prognostic biomarkers related to GBM.

Hypoxia-inducible lncRNA MIR210HG interacting with OCT1 is involved in glioblastoma multiforme malignancy.

An insufficient oxygen supply within the intratumoral environment, also known as hypoxia, induces glioblastoma multiforme (GBM) invasion, stemness, and temozolomide (TMZ) drug resistance. Long noncoding (lnc)RNAs have been reported to be involved in hypoxia and GBM progression. However, their roles in hypoxic GBM malignancy are still unclear. We investigated the mechanisms of hypoxia‐mediated lncRNAs in regulating GBM processes. Using The Cancer Genome Atlas (TCGA) and data mining, hypoxia‐correlated lncRNAs were identified. A hypoxia‐upregulated lncRNA, MIR210HG, locating in nuclear regions, predicted poor prognoses of patients and modulated hypoxia‐promoted glioma stemness, TMZ resistance, and invasion. Depletion of hypoxic MIR210HG suppressed GBM and patient‐derived cell growth and increased TMZ sensitivity in vitro and vivo. Using RNA sequencing and gene set enrichment analysis (GSEA), MIR210HG‐upregulated genes significantly belonged to the targets of octamer transcription factor 1 (OCT1) transcription factor. The direct interaction between OCT1 and MIR210HG was also validated. Two well‐established worse prognostic factors of GBM, insulin‐like growth factor–binding protein 2 (IGFBP2) and fibroblast growth factor receptor 1 (FGFR1), were identified as downstream targets of OCT1 through MIR210HG mediation in hypoxia. Consequently, the lncRNA MIR210HG is upregulated by hypoxia and interacts with OCT1 for modulating hypoxic GBM, leading to poor prognoses. These findings might provide a better understanding in functions of hypoxia/MIR210HG signaling for regulating GBM malignancy.

Magnolol Induces the Extrinsic/Intrinsic Apoptosis Pathways and Inhibits STAT3 Signaling-Mediated Invasion of Glioblastoma Cells.

Glioblastoma multiforme (GBM) is the most common form of malignant brain tumor, with poor prognosis; the efficacy of current standard therapy for GBM remains unsatisfactory. Magnolol, an herbal medicine from Magnolia officinalis, exhibited anticancer properties against many types of cancers. However, whether magnolol suppresses GBM progression as well as its underlying mechanism awaits further investigation. In this study, we used the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay, apoptosis marker analysis, transwell invasion and wound-healing assays to identify the effects of magnolol on GBM cells. We also validated the potential targets of magnolol on GBM with the GEPIA (Gene Expression Profiling Interactive Analysis) and Western blotting assay. Magnolol was found to trigger cytotoxicity and activate extrinsic/intrinsic apoptosis pathways in GBM cells. Both caspase-8 and caspase-9 were activated by magnolol. In addition, GEPIA data indicated the PKCδ (Protein kinase C delta)/STAT3 (Signal transducer and activator of transcription 3) signaling pathway as a potential target of GBM. Magnolol effectively suppressed the phosphorylation and nuclear translocation of STAT3 in GBM cells. Meanwhile, tumor invasion and migration ability and the associated genes, including MMP-9 (Matrix metalloproteinase-9) and uPA (Urokinase-type plasminogen activator), were all diminished by treatment with magnolol. Taken together, our results suggest that magnolol-induced anti-GBM effect may be associated with the inactivation of PKCδ/STAT3 signaling transduction.