Glioma Cell Migration Research Articles

Retraction: Downregulated microRNA-30b-3p inhibits proliferation, invasion and migration of glioma cells via inactivation of the AKT signaling pathway by upregulating RECK.

Retraction: Downregulated microRNA-30b-3p inhibits proliferation, invasion and migration of glioma cells via inactivation of the AKT signaling pathway by upregulating RECK.

Effect of circFOXM1/miR-218-5p on the proliferation, apoptosis and migration of glioma cells.

This study aimed to explore the influence of circFOXM1/miR-218-5p molecular axis in the proliferation, apoptosis and migration of glioma cells. The levels of circFOXM1 and miR-218-5p in glioma and adjacent tissues were tested by qRT-PCR. Cultured human glioma U251 cells were randomly split into groups: si-NC, si-circFOXM1, miR-NC, miR-218-5p, si-circFOXM1+anti-miR-NC, si-circFOXM1+anti-miR-218-5p. MTT method, plate clone formation, flow cytometry and Transwell experiments were utilized for detecting the proliferation, clone formation, apoptosis and migration of glioma cells. Dual-luciferase reporter experiment authenticated the targeted relation of circFOXM1 and miR-218-5p. Western blot tested the levels of E-cadherin and N-cadherin. CircFOXM1 was upregulated while miR-218-5p was low expressed in glioma tissues versus normal tissues. After circFOXM1 silence or miR-218-5p overexpression, miR-218-5p level was increased, and cell apoptosis rate and E-cadherin expression were enhancive, whereas cell proliferation, cell clone formation and migration abilities, and N-cadherin level were reduced. CircFOXM1 could affect miR-218-5 level by negative regulation. Furthermore, miR-218-5p silence could reverse the stimulative influence of si-circFOXM1 on apoptosis rate, and E-cadherin level, and the repressive effect on cell viability, cell number of colony formation and migration, and N-cadherin expression. Inhibition of circFOXM1 expression could block the proliferation, clone formation, and migration and induce apoptosis of glioma cells by upregulating miR-218-5p.

PKM2 promotes glioma progression by mediating CTNNB1 expression

ABSTRACT Background Glioma is a common intracranial tumor, exhibiting a high degree of aggressiveness and invasiveness. Pyruvate kinase M2 (PKM2) is overexpressed in glioma tissues. However, the biological role of PKM2 in glioma is unclear. Methods The qRT-PCR, CCK-8, Transwell, flow cytometry detection, western blot assays, ELISA assay, and pyruvate kinase activity assays were performed in glioma cells transfected with PKM2 shRNA to explore the function of PKM2 in glioma progression. Then, STRING website was used to predict the proteins that interacted with PKM2, and Co-IP assay was conducted to further validate their interaction. Subsequently, the above experiments were performed again to find the effect of catenin beta 1 (CTNNB1) overexpression on PKM2-deficient glioma cells. The transplanted tumor models were also established to further validate our findings. Results PKM2 was up-regulated in glioma cells and tissues. After inhibiting PKM2, the proliferation, migration, glycolysis, and EMT of glioma cells were significantly decreased, and the proportion of apoptosis was increased. The prediction results of STRING website showed that CTNNB1 and PKM2 had the highest interaction score. The correlation between CTNNB1 and PKM2 was further confirmed by Co-IP test. PKM2 knockdown suppressed glioma cell proliferation, migration, glycolysis, and EMT, while CTNNB1 overexpression rescued these inhibitory effects. Correspondingly, PKM2 knockdown inhibited glioma growth in vivo. Conclusion In summary, these findings indicated that PKM2 promotes glioma progression by mediating CTNNB1 expression, providing a possible molecular marker for the clinical management of gliomas.

Nuclear Rac1 controls nuclear architecture and cell migration of glioma cells

Rac1 (Ras-related C3 botulinum toxin substrate 1) protein has been found in the cell nucleus many years ago, however, its nuclear functions are still poorly characterized but some data suggest its nuclear accumulation in cancers. We investigated nuclear Rac1 in glioma cancer cells nuclei and compared its levels and activity to normal astrocytes, and also characterized the studied cells on various nuclear properties and cell migration patterns.Nuclear Rac1 indeed was found accumulated in glioma cells, but only a small percentage of the protein was in active, GTP-bound state in comparison to healthy control. Altering the nuclear activity of Rac1 influenced chromatin architecture and cell motility in GTP-dependent and independent manner. This suggests that the landscape of Rac1 nuclear interactions might be as complicated and wide as its well-known, non-nuclear signaling.

Metabolic Roles of HIF1, c-Myc, and p53 in Glioma Cells.

The metabolic reprogramming that promotes tumorigenesis in glioblastoma is induced by dynamic alterations in the hypoxic tumor microenvironment, as well as in transcriptional and signaling networks, which result in changes in global genetic expression. The signaling pathways PI3K/AKT/mTOR and RAS/RAF/MEK/ERK stimulate cell metabolism, either directly or indirectly, by modulating the transcriptional factors p53, HIF1, and c-Myc. The overexpression of HIF1 and c-Myc, master regulators of cellular metabolism, is a key contributor to the synthesis of bioenergetic molecules that mediate glioma cell transformation, proliferation, survival, migration, and invasion by modifying the transcription levels of key gene groups involved in metabolism. Meanwhile, the tumor-suppressing protein p53, which negatively regulates HIF1 and c-Myc, is often lost in glioblastoma. Alterations in this triad of transcriptional factors induce a metabolic shift in glioma cells that allows them to adapt and survive changes such as mutations, hypoxia, acidosis, the presence of reactive oxygen species, and nutrient deprivation, by modulating the activity and expression of signaling molecules, enzymes, metabolites, transporters, and regulators involved in glycolysis and glutamine metabolism, the pentose phosphate cycle, the tricarboxylic acid cycle, and oxidative phosphorylation, as well as the synthesis and degradation of fatty acids and nucleic acids. This review summarizes our current knowledge on the role of HIF1, c-Myc, and p53 in the genic regulatory network for metabolism in glioma cells, as well as potential therapeutic inhibitors of these factors.

Open-Top Patterned Hydrogel-Laden 3D Glioma Cell Cultures for Creation of Dynamic Chemotactic Gradients to Direct Cell Migration.

The laminar flow profiles in microfluidic systems coupled to rapid diffusion at flow streamlines have been widely utilized to create well-controlled chemical gradients in cell cultures for spatially directing cell migration. However, within hydrogel-based closed microfluidic systems of limited depth (≤0.1 mm), the biomechanical cues for the cell culture are dominated by cell interactions with channel surfaces rather than with the hydrogel microenvironment. Also, leaching of poly(dimethylsiloxane) (PDMS) constituents in closed systems and the adsorption of small molecules to PDMS alter chemotactic profiles. To address these limitations, we present the patterning and integration of a PDMS-free open fluidic system, wherein the cell-laden hydrogel directly adjoins longitudinal channels that are designed to create chemotactic gradients across the 3D culture width, while maintaining uniformity across its ∼1 mm depth to enhance cell-biomaterial interactions. This hydrogel-based open fluidic system is assessed for its ability to direct migration of U87 glioma cells using a hybrid hydrogel that includes hyaluronic acid (HA) to mimic the brain tumor microenvironment and gelatin methacrylate (GelMA) to offer the adhesion motifs for promoting cell migration. Chemotactic gradients to induce cell migration across the hydrogel width are assessed using the chemokine CXCL12, and its inhibition by AMD3100 is validated. This open-top hydrogel-based fluidic system to deliver chemoattractant cues over square-centimeter-scale areas and millimeter-scale depths can potentially serve as a robust screening platform to assess emerging glioma models and chemotherapeutic agents to eradicate them.

The role of ST3GAL4 in glioma malignancy, macrophage infiltration, and prognostic outcomes

BackgroundGlioma, a prevalent malignancy of the brain and spinal cord, poses a considerable threat to human health. The association between aberrant sialic acid modification and glioma progression has been suggested, but the precise mechanism is still elusive. ST3GAL4, a sialoglycosyltransferase, is implicated in increased metastatic potential and poor prognosis in various cancers; however, its specific role in glioma requires further elucidation. MethodsWe evaluated ST3GAL4 expression levels and their clinical relevance using the TCGA database, and we assessed immune infiltration via the Tumor Immune Evaluation Resource (TIMER) database. In vitro experiments were performed to determine the effects of ST3GAL4 knockdown on glioma cell malignancy, with additional co-culture assays to assess its impact on macrophage phenotype. ResultsST3GAL4 expression was markedly elevated in glioma tissues compared to normal brain tissues, with a strong correlation to glioma patient clinical characteristics. Survival analyses and receiver operating characteristic (ROC) curves suggested that ST3GAL4 is a feasible diagnostic and prognostic biomarker for glioma. Knockdown studies revealed that ST3GAL4 inhibition reduces glioma cell line proliferation, migration, and invasion, while causing G1 phase cell cycle arrest. ST3GAL4 appears to mediate glioma progression through extracellular matrix reorganization and EMT signaling pathway activation, further contributing to M2 macrophage polarization and infiltration within the tumor microenvironment. ConclusionOur research highlights the critical role of ST3GAL4 in glioma development, positioning it as a promising candidate for diagnostic and therapeutic interventions.

Integration analysis of cell division cycle-associated family genes revealed potential mechanisms of gliomagenesis and constructed an artificial intelligence-driven prognostic signature

Cell division cycle-associated (CDCA) gene family members are essential cell proliferation regulators and play critical roles in various cancers. However, the function of the CDCA family genes in gliomas remains unclear. This study aims to elucidate the role of CDCA family members in gliomas using in vitro and in vivo experiments and bioinformatic analyses. We included eight glioma cohorts in this study. An unsupervised clustering algorithm was used to identify novel CDCA gene family clusters. Then, we utilized multi-omics data to elucidate the prognostic disparities, biological functionalities, genomic alterations, and immune microenvironment among glioma patients. Subsequently, the scRNA-seq analysis and spatial transcriptomic sequencing analysis were carried out to explore the expression distribution of CDCA2 in glioma samples. In vivo and in vitro experiments were used to investigate the effects of CDCA2 on the viability, migration, and invasion of glioma cells. Finally, based on ten machine-learning algorithms, we constructed an artificial intelligence-driven CDCA gene family signature called the machine learning-based CDCA gene family score (MLCS). Our results suggested that patients with the higher expression levels of CDCA family genes had a worse prognosis, more activated RAS signaling pathways, and more activated immunosuppressive microenvironments. CDCA2 knockdown inhibited the proliferation, migration, and invasion of glioma cells. In addition, the MLCS had robust and favorable prognostic predictive ability and could predict the response to immunotherapy and chemotherapy drug sensitivity.

NCAPH serves as a prognostic factor and promotes the tumor progression in glioma through PI3K/AKT signaling pathway.

Non-SMC (Structural Maintenance of Chromosomes) condensin I complex subunit H (NCAPH) has been shown to facilitate progression and predict adverse prognostic outcome in many cancer types. However, the function of NCAPH in gliomas is still unclear. Series of experiments were taken to uncover the function of NCAPH in glioma. The expression of NCAPH and potential mechanism regulating progression of glioma was verified by bioinformatics analysis. Lentiviral transfection was used for establishment of loss-of-function and gain-of-function cell lines. CCK-8 assay and Colony-formation assay were used to evaluate proliferation. Transwell assay and Cell wound healing assay were used to assess migration and invasion. Cell cycle and apoptosis were measured by flow cytometry. Protein and RNA were quantified by WB and RT-PCR, respectively. The nude mice model of glioma was used to evaluate the effect of NCAPH in vivo. The expression of NCAPH increased significantly in glioma tissues and correlated with WHO grade, IDH wild-type and non-1p/19q codeletion. Glioma patients with high expression of NCAPH had an undesirable prognosis. Functionally, upregulated NCAPH promotes the malignant hallmarks of glioma cells in vivo and in vitro. NCAPH correlated with DNA damage repair ability of glioma cells and facilitated the proliferation, invasion, and migration of glioma cells by promoting the PI3K/AKT signaling pathway. This study identifies the important pro-tumor role of NCAPH in glioma and suggests that NCAPH is a potential therapeutic target.

Knockdown of PGBD5 inhibits the malignant progression of glioma through upregulation of the PPAR pathway.

Glioma is the most common type of primary intracranial malignant tumor, and because of its high invasiveness and recurrence, its prognosis remains poor. The present study investigated the biological function of piggyBac transportable element derived 5 (PGBD5) in glioma. Glioma and para-cancerous tissues were obtained from five patients. Reverse transcription-quantitative PCR and western blotting were used to detect the expression levels of PGBD5. Transwell assay and flow cytometry were used to evaluate cell migration, invasion, apoptosis and cell cycle distribution. In addition, a nude mouse tumor transplantation model was established to study the downstream pathways of PGBD5 and the molecular mechanism was analyzed using transcriptome sequencing. The mRNA and protein expression levels of PGBD5 were increased in glioma tissues and cells. Notably, knockdown of PGBD5 in vitro could inhibit the migration and invasion of glioma cells. In addition, the knockdown of PGBD5 expression promoted apoptosis and caused cell cycle arrest in the G2/M phase, thus inhibiting cell proliferation. Furthermore, in vivo experiments revealed that knockdown of PGBD5 expression could inhibit Ki67 expression and slow tumor growth. Changes in PGBD5 expression were also shown to be closely related to the peroxisome proliferator-activated receptor (PPAR) signaling pathway. In conclusion, interference with PGBD5 could inhibit the malignant progression of glioma through the PPAR pathway, suggesting that PGBD5 may be a potential molecular target of glioma.

Has-miR-134-5p inhibits the proliferation and migration of glioma cells by regulating the BDNF/ERK signaling pathway.

Our research investigated the effects of hsa-miR-134-5p on glioma progression, focusing on its interaction with the BDNF/ERK signaling pathway. U251 and U87 cell lines were analyzed post-transfection with hsa-miR-134-5p mimics and inhibitors, confirming the miRNA's binding to BDNF using dual luciferase assays. Q-PCR was employed to measure expression changes, revealing that hsa-miR-134-5p markedly inhibited glioma cell proliferation, migration, and invasion, as evidenced by CCK8, monoclonal formation, and Transwell assays. Scratch tests and Western blotting demonstrated hsa-miR-134-5p's modulation of the BDNF/ERK pathway and associated decrease in MMP2/9 protein levels. Flow cytometry suggested that hsa-miR-134-5p might also block the G0/S phase transition. In vivo studies using nude mice corroborated the tumor-suppressing effects of hsa-miR-134-5p, which were negated by elevated BDNF levels. Comparative protein analysis across groups confirmed the pathway's significance in tumorigenesis. Our findings identify hsa-miR-134-5p as a key molecule impeding glioma cell growth by curtailing the BDNF/ERK pathway, with the reversal by BDNF upregulation pointing to the potential of therapeutically exploiting the hsa-miR-134-5p/BDNF axis in glioma care.

GPR65 sensing tumor-derived lactate induces HMGB1 release from TAM via the cAMP/PKA/CREB pathway to promote glioma progression

BackgroundLactate has emerged as a critical regulator within the tumor microenvironment, including glioma. However, the precise mechanisms underlying how lactate influences the communication between tumor cells and tumor-associated macrophages (TAMs), the most abundant immune cells in glioma, remain poorly understood. This study aims to elucidate the impact of tumor-derived lactate on TAMs and investigate the regulatory pathways governing TAM-mediated tumor-promotion in glioma.MethodsBioinformatic analysis was conducted using datasets from TCGA and CGGA. Single-cell RNA-seq datasets were analyzed by using UCSC Cell Browser and Single Cell Portal. Cell proliferation and mobility were evaluated through CCK8, colony formation, wound healing, and transwell assays. Western blot and immunofluorescence staining were applied to assess protein expression and cell distribution. RT-PCR and ELISA were employed to identify the potential secretory factors. Mechanistic pathways were explored by western blotting, ELISA, shRNA knockdown, and specific inhibitors and activators. The effects of pathway blockades were further assessed using subcutaneous and intracranial xenograft tumor models in vivo.ResultsElevated expressions of LDHA and MCT1 were observed in glioma and exhibited a positive correlation with M2-type TAM infiltration. Lactate derived from glioma cells induced TAMs towards M2-subtype polarization, subsequently promoting glioma cells proliferation, migration, invasion, and mesenchymal transition. GPR65, highly expressed on TAMs, sensed lactate-stimulation in the TME, fueling glioma cells malignant progression through the secretion of HMGB1. GPR65 on TAMs triggered HMGB1 release in response to lactate stimulation via the cAMP/PKA/CREB signaling pathway. Disrupting this feedback loop by GPR65-knockdown or HMGB1 inhibition mitigated glioma progression in vivo.ConclusionThese findings unveil the intricate interplay between TAMs and tumor cells mediated by lactate and HMGB1, driving tumor progression in glioma. GPR65, selectively highly expressed on TAMs in glioma, sensed lactate stimulation and fostered HMGB1 secretion via the cAMP/PKA/CREB signaling pathway. Blocking this feedback loop presents a promising therapeutic strategy for GBM.

DNA Damage-Induced Apoptosis Suppressor Triggers Progression and Stemness of Glioma by Enhancing Lymphoid Enhancer-Binding Factor 1 Expression.

DNA damage-induced apoptosis suppressor (DDIAS) has recently been discovered to induce cancer progression, but its functions and mechanisms in glioma have not been well studied. DDIAS expression in glioma tissues was analyzed by the Gene Expression Profiling Interactive Analysis server (GEPIA) and the Gene Expression database of Normal and Tumor tissue 2 (GENT2) databases. The role of DDIAS in glioma progression was studied by short hairpin RNA (shRNA) targeting DDIAS. The effects of DDIAS on glioma cell viability, cell proliferation, invasion, migration, and tumor sphere formation were determined by cell counting kit-8 (CCK-8), EdU, Transwell, tumor spheroid formation, extreme limiting dilution analysis assays in vitro and xenograft model construction in vivo. In addition, RNA sequencing and further functional experiments were used to analyze the DDIAS regulatory mechanism in glioma. We found that DDIAS was highly expressed in glioma and that upregulated DDIAS indicated poor prognosis. Functionally, DDIAS knockdown inhibited glioma cell viability, cell proliferation, invasion and migration in vitro and tumor growth in vivo. In addition, lymphoid enhancer-binding factor 1 (LEF1) was identified as the downstream effector of DDIAS by RNA sequencing. DDIAS downregulation inhibited LEF1 mRNA and protein expression. The expression of DDIAS and LEF1 was positively correlated, and LEF1 overexpression rescued the inhibitory phenotype induced by DDIAS downregulation. We further showed that DDIAS downregulation inhibited cyclin A1, vimentin and the stemness-related factor CD133 and decreased the sphere formation capability, but these features were rescued by upregulation of LEF1. Taken together, these findings suggest that DDIAS promotes glioma progression and stemness by inducing LEF1 expression, proving that DDIAS may be a potential target for the treatment of glioma.

Network pharmacology-based investigation of the effects of Shenqi Fuzheng injection on glioma proliferation and migration via the SRC/PI3K/AKT signaling pathway

Ethnopharmacological relevanceIn the clinic, Shenqi Fuzheng Injection (SFI) is used as an adjuvant for cancer chemotherapy. However, the molecular mechanism is unclear. Aim of the studyWe screened potential targets of SFI action on gliomas by network pharmacology and performed experiments to validate possible molecular mechanisms against gliomas. Materials and methodsWe consulted relevant reports on the SFI and glioma incidence from PubMed and Web of Science and focused on the mechanism through which the SFI inhibits glioma. According to the literature, two primary SFI components—Codonopsis pilosula (Franch.) Nannf. and Astragalus membranaceus (Fisch.) Bunge—have been found. All plant names have been sourced from "The Plant List" (www.theplantlist.org). The cell lines U87, T98G and GL261 were used in this study. The inhibitory effects of SFI on glioma cells U87 and T98G were detected by CCK-8 assay, EdU, plate cloning assay, scratch assay, Transwell assay, immunofluorescence, flow cytometry and Western blot. A subcutaneous tumor model of C57BL/6 mice was constructed using GL261 cells, and the SFI was evaluated by HE staining and immunohistochemistry. The targets of glioma and the SFI were screened using network pharmacology. ResultsA total of 110 targets were enriched, and a total of 26 major active components in the SFI were investigated. There were a total of 3,343 targets for gliomas, of which 79 targets were shared between the SFI and glioma tissues. SFI successfully prevented proliferation and caused cellular S-phase blockage in U87 and T98G cells, thus decreasing their growth. Furthermore, SFI suppressed cell migration by downregulating EMT marker expression. According to the results of the in vivo tests, the SFI dramatically decreased the development of tumors in a transplanted tumour model. Network pharmacological studies revealed that the SRC/PI3K/AKT signaling pathway may be the pathway through which SFI exerts its anti-glioma effects. ConclusionsThe findings revealed that the SRC/PI3K/AKT signaling pathway may be involved in the mechanism through which SFI inhibits the proliferation and migration of glioma cells.

High expression of RTEL1 predicates worse progression in gliomas and promotes tumorigenesis through JNK/ELK1 cascade

Gliomas are the most common primary intracranial tumor worldwide. The maintenance of telomeres serves as an important biomarker of some subtypes of glioma. In order to investigate the biological role of RTEL1 in glioma. Relative telomere length (RTL) and RTEL1 mRNA was explored and regression analysis was performed to further examine the relationship of the RTL and the expression of RTEL1 with clinicopathological characteristics of glioma patients. We observed that high expression of RTEL1 is positively correlated with telomere length in glioma tissue, and serve as a poor prognostic factor in TERT wild-type patients. Further in vitro studies demonstrate that RTEL1 promoted proliferation, formation, migration and invasion ability of glioma cells. In addition, in vivo studies also revealed the oncogene role of RTEL1 in glioma. Further study using RNA sequence and phospho-specific antibody microarray assays identified JNK/ELK1 signaling was up-regulated by RTEL1 in glioma cells through ROS. In conclusion, our results suggested that RTEL1 promotes glioma tumorigenesis through JNK/ELK1 cascade and indicate that RTEL1 may be a prognostic biomarker in gliomas.

CD13 expression affects glioma patient survival and influences key functions of human glioblastoma cell lines in vitro

CD13 (APN) is an Alanyl-Aminopeptidase with diverse functions. The role of CD13 for gliomas is still unknown. In this study, data of glioma patients obtained by TCGA and CGGA databases were used to evaluate the survival rate and prognostic value of CD13 expression level. Protein expression of CD13 was confirmed by immunofluorescence staining of fresh patient tissues. Eight human glioblastoma cell lines were studied by RT-PCR, Western Blot, immunofluorescence staining and flow cytometry to define CD13 expression. Cell lines with different CD13 expression status were treated with a CD13 inhibitor, bestatin, and examined by MTT, scratch and colony formation assaysas well as by apoptosis assay and Western Blots. Bioinformatics analysis indicated that patients with high expression of CD13 had poor survival and prognosis. Additionally, CD13 protein expression was positively associated with clinical malignant characteristics. Investigated glioblastoma cell lines showed distinct expression levels and subcellular localization of CD13 with intracellular enrichment. Bestatin treatment reduced proliferation, migration and colony formation of glioma cells in a CD13-dependent manner while apoptosis was increased. In summary, CD13 has an impact on glioma patient survival and is important for the main function of specific glioma cells.

Abstract 3355: Unraveling the molecular mechanisms of glioma migration: Exploring the role of cell intrinsic and stromal ephrin receptor-ligand signaling

Abstract Diffuse invasion, a hallmark of malignant gliomas, makes these tumors surgically incurable and is the ultimate cause of death. While glioma cells can migrate along blood vessels and in neuron-rich regions, their preferred route of migration is along white matter (WM) tracts, which allows tumor cells to spread to the contralateral hemisphere with devastating neurocognitive consequences. The underlying mechanisms of in vivo glioma cell migration are poorly understood. There is emerging evidence that glioblastoma multiforme (GBM) cells may hijack migration mechanisms used during brain development. Accordingly, we used a neonatal plasmid electroporation GBM model (CRISPR-Cas9, -Cre,gRNAs targeting NF1, p53, PTEN, and piggyBac-glast) to generate a highly penetrant diffusely invasive glioma models with preference for migration along myelinated fiber tracts including the corpus callosum (CC). To test the in vivo role of integrin-mediated migration, tumors were generated using conditional integrin β1f/f (ITGB1) or focal adhesion kinase (FAKf/f) mice. Both ITGB1 and FAK null GBM cells (confirmed by western blot analysis) showed diffuse infiltration similar to WT mice, suggesting that integrin signaling is not essential for in vivo GBM cell migration. Next, we tested the role ephrin-signaling using a series of transgenic neonatal mice, including EPH-B1-/-, -B2-/-, -B1/2-/-, -kinase-dead (KD) and a gain-of-function mutant). EPH1/2-/- GBM, but not the other genetic models, consistently formed tumors which showed no diffuse single-cell infiltration, but rather grew as a solid expanding mass. An extensive panel of in vitro studies comparing WT and EPHB1/2-/- GBM patterns of growth and migration, including time-lapse random walk, neurosphere radial migration, migration along patterned surfaces, and laminin-coated confined 3D channels, showed similar patterns of migration, despite the marked differences in vivo. These contrasting in vivo and in vitro results raise the possibility that EPH-B1/2 receptors may require their cognate ephrin ligands to facilitate migration through the WM tracts. To test this hypothesis, we are using Ephrin-B1f/f, B2f/f mice for in vivo cell-type specific deletion in WM tract stroma cells and primary astrocytes derived from these mice for ex vivo co-culture studies. Our preliminary data suggest that EPH/EPHRIN interactions may regulate GBM cell migration. Citation Format: Jesung Moon, Xiaofei Gao, Peiguo Ding, Fnu Bilal, Smita Rindhe, Ning Gao, Digant P. Dave, Mark Henkemeyer, Elizabeth A. Maher, Robert M. Bachoo. Unraveling the molecular mechanisms of glioma migration: Exploring the role of cell intrinsic and stromal ephrin receptor-ligand signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3355.

Identification of CREB5 as a prognostic and immunotherapeutic biomarker in glioma through multi-omics pan-cancer analysis

BackgroundThe functional relevance of cyclic adenosine monophosphate (cAMP)-response element-binding protein 5 (CREB5) in cancers remains elusive, despite its significance as a member of the CREB family. The current research aims to explore the role of CREB5 in multiple cancers. MethodsPan-cancer analysis was performed to explore the expression patterns, prognostic value, mutational landscape as well as single-cell omic, immunologic, and drug sensitivity profiles of CREB5. Furthermore, we incorporated five distinct machine learning algorithms and determined that the least absolute shrinkage and selection operator-COX (LASSO-COX) algorithm, which exhibited the highest C index, was the optimal selection. Subsequently, we constructed a prognostic model centered around CREB5-associated genes. To elucidate the biological function of CREB5 in glioma cells, several assays including cell counting kit-8 (CCK-8), wound healing, transwell, flow cytometric were performed. ResultsCREB5 was overexpressed in pan-cancer and was linked to unfavorable prognosis, particularly in glioma. Furthermore, genetic alterations were determined in various types of cancer, and modifications in the CREB5 gene were linked to the prognosis. The single-cell omics and enrichment analyses showed that CREB5 was predominantly expressed in malignant glioma cells and was critically involved in the regulation of various oncogenic processes. Elevated levels of CREB5 were strongly linked with the infiltration of cancer-associated fibroblasts and the Th1 subset of CD4+ T cells. The validated CREB5-associated prognostic model reliably predicted the prognosis and drug response of glioma patients. The in vitro experiments showed that CREB5 promoted glioma cell proliferation, invasion, migration, and gap phase 2/mitotic (G2/M) phase arrest and recruited M2 macrophages into glioma cells. ConclusionCREB5 has the potential to act as an oncogene and a biological marker in multiple cancers, particularly glioma.

MiR-26-3p regulates proliferation, migration, invasion and apoptosis of glioma cells by targeting CREB1

To investigate the regulatory role of miR-26b-3p in proliferation, migration and invasion of glioma. The expressions of miR-26b-3p and cAMP-responsive element binding protein 1 (CREB1) in gliomas of different pathological grades were detected with RT-qPCR and Western blotting. Bioinformatic methods were used to analyze the target sequence of miRNA-26b-3p binding to CREB1, and dual luciferase gene reporter experiment was performed to explore the mechanism for targeted regulation of CREB1 by miR-26b-3p. Glioma U251 cells were treated with miR-26b-3p mimic or inhibitor, and the changes in CREB1 expression and cell proliferation, migration, invasion and apoptosis were determined with Western blotting, CCK-8 assay, wound healing assay, Transwell assay, and flow cytometry. The expression of miR-26b-3p decreased while CREB1 expression increased significantly as the pathological grade of gliomas increased (P < 0.05). Dual luciferase gene reporter experiment confirmed that CREB1 was a downstream target of miR-26b-3p. Inhibition of miR-26b-3p significantly upregulated the expression of CERB1, suppressed apoptosis and promoted proliferation and invasion of glioma cells, and overexpression of miR-26b-3p produced the opposite effects (P < 0.05). MiR-26b-3p regulates CREB1 expression to modulate apoptosis, proliferation, migration and invasion of glioma cells, thereby participating in tumorigenesis and progression of glioma.

PSMB2 plays an oncogenic role in glioma and correlates to the immune microenvironment

There has been an upward trend in the incidence of glioma, with high recurrence and high mortality. The beta subunits of the 20S proteasome are encoded by the proteasome beta (PSMB) genes and may affect the proteasome’s function in glioma, assembly and inhibitor binding. This study attempted to reveal the function of the proliferation and invasion of glioma cells, which is affected by proteasome 20S subunit beta 2 (PSMB2). We subjected the data downloaded from the TCGA database to ROC, survival, and enrichment analyses. After establishing the stable PSMB2 knockdown glioma cell line. We detect the changes in the proliferation, invasion and migration of glioma cells by plate colony formation assay, transwell assay, wound healing assay and flow cytometry and PSMB2 expression was verified by quantitative PCR and Western blotting to identify the mRNA and protein levels. PSMB2 expression was higher in glioma tissues, and its expression positively correlated with poor prognosis and high tumor grade and after PSMB2 knockdown, the proliferation, invasion and migration of glioma cells were weakened.