Glioma Cell Proliferation Research Articles

FXR1 promotes glioma progression by downregulating microRNA-124-3p through long noncoding RNA FGD5-AS1 upregulation.

As reported, glioma progression is affected by altered FXR1, long non-coding RNA FGD5-AS1, and microRNA (miR)-124-3p. However, relationships among these genes remain unclear. Accordingly, this paper ascertains whether FXR1 manipulates glioma progression via the FGD5-AS1/miR-124-3p axis. Glioma tissues were harvested, in which FGD5-AS1 and miR-124-3p levels were examined with qRT-PCR and FXR1 level was assessed with qRT-PCR and western blot. The interaction of miR-124-3p with FGD5-AS1 was analyzed by dual-luciferase reporter, RIP, and Pearson correlation coefficient assays, and that of FXR1 with FGD5-AS1 was assessed by RIP and Pearson correlation coefficient assays. Glioma cells were obtained, followed by qRT-PCR detection of miR-124-3p expression. After gain- or loss-of-function assays, EdU, Transwell, and tubule formation assays were performed to determine cell proliferation, invasion and migration, and angiogenesis. Next, the intracranial in situ graft tumor model was established for in vivo verification. FGD5-AS1 and FXR1 levels were high, but miR-124-3p level was low in glioma tissues. Likewise, glioma cells had downregulated miR-124-3p expression. Mechanistically, FGD5-AS1 negatively bound to miR-124-3p, and FXR1 was positively correlated and interacted with FGD5-AS1. miR-124-3p overexpression or FGD5-AS1 or FXR1 knockdown restricted cell invasion, proliferation, migration, and angiogenesis in gliomas. miR-124-3p inhibition abrogated the repressive impacts of FXR1 knockdown on the malignant progression of gliomas. Also, FXR1 constrained tumor growth and angiogenesis in mice, which was counterweighed by inhibiting miR-124-3p. FXR1 might act as an oncogene in gliomas by declining miR-124-3p through FGD5-AS1.

Lycium barbarum glycopeptide targets PER2 to inhibit lipogenesis in glioblastoma by downregulating SREBP1c.

Lycium barbarum polysaccharide (LBP) is a substance with various biological activities extracted from Lycium barbarum. LbGPs are peptidoglycans with a short peptide backbone and a complex, branched glycan moiety, which is further extracted and isolated from LBPs. Previous studies have shown that LbGP can inhibit cancer cell growth, but its specific mechanism is not completely clear. In this study, we found that LbGP could inhibit the proliferation of glioma cells and promote the expression of period 2 (PER2) through the PKA-CREB pathway. In addition, LbGP could inhibit the de novo synthesis of lipids by downregulating SREBP1c and its target genes, which depended on the expression of PER2. Moreover, PER2 negatively regulated the expression of SREBP1c via suppressing PI3K/AKT/mTOR pathway. In summary, LbGP may upregulate the expression of PER2 to reduce the expression of SREBP1c, inhibit lipid synthesis in glioblastoma, and inhibit glioblastoma cell proliferation. This study provides an alternative drug for the treatment of glioma and elucidates its potential mechanism.

Potassium Ion Channels in Glioma: From Basic Knowledge into Therapeutic Applications.

Ion channels, specifically those controlling the flux of potassium across cell membranes, have recently been shown to exhibit an important role in the pathophysiology of glioma, the most common primary central nervous system tumor with a poor prognosis. Potassium channels are grouped into four subfamilies differing by their domain structure, gating mechanisms, and functions. Pertinent literature indicates the vital functions of potassium channels in many aspects of glioma carcinogenesis, including proliferation, migration, and apoptosis. The dysfunction of potassium channels can result in pro-proliferative signals that are highly related to calcium signaling as well. Moreover, this dysfunction can feed into migration and metastasis, most likely by increasing the osmotic pressure of cells allowing the cells to initiate the "escape" and "invasion" of capillaries. Reducing the expression or channel blockage has shown efficacy in reducing the proliferation and infiltration of glioma cells as well as inducing apoptosis, priming several approaches to target potassium channels in gliomas pharmacologically. This review summarizes the current knowledge on potassium channels, their contribution to oncogenic transformations in glioma, and the existing perspectives on utilizing them as potential targets for therapy.

Circular RNA XRCC5 aggravates glioma progression by activating CLC3/SGK1 axis via recruiting IGF2BP2

BackgroundIncreasing evidences have reported the critical roles of circular RNA (circRNA) in gliomas. Whereas, the role of circXRCC5 in glioma and its underlying molecular mechanism has not been reported. MethodsThe RNA transcripts and protein levels were detected using qRT-PCR, immunohistochemistry (IHC) and in situ hybridization (ISH) assays. Cell proliferation was characterized by CCK-8 and clone formation assays. The formation of NLRP3-inflammasomes was identified using immunofluorescence (IF) and Western blot assays. The cytokines were determined using immunosorbent assay (ELISA) and Western blot assays. The molecular interactions were validated using RIP and pull-down assays. ResultscircXRCC5 was over-expressed in glioma and positively related to the shorter survival rate, advanced TNM stage and larger tumor volume. circXRCC5 knockdown inhibited cell proliferation and NLRP3-mediated inflammasome activation of glioma cells. Subsequently, we found that circXRCC5 maintained mRNA stability of CLC3 by binding to IGF2BP2. Furthermore, CLC3 accelerated SGK1 expression via PI3K/PDK1/AKT pathway. The rescue experiments showed that both overexpression of CLC3 or SGK1 dramatically alleviated circXRCC5 knockdown-induced inhibition of cell proliferation and NLRP3-mediated inflammasome activation of glioma cells. In vivo, our study proved that circXRCC5 accelerated glioma growth by regulating CLC3/SGK1 axis. ConclusionOur data concluded that circXRCC5 formed a complex with IGF2BP2 to regulate inflammasome activation and tumor growth via CLC3/SGK1 axis.

LncRNA TUSC7 sponges miR-10a-5p and inhibits BDNF/ERK pathway to suppress glioma cell proliferation and migration.

Gliomas as primary cerebral malignancies frequently occurring in adults have relatively high morbidity and mortality. The underlying role of long non-coding ribonucleic acids (lncRNAs) in malignancies has attracted much attention, among which tumor suppressor candidate 7 (TUSC7) is a novel tumor suppressor gene whose regulatory mechanism in human cerebral gliomas remains inconclusive. In this study, bioinformatics analysis indicated that TUSC7 could specifically bind to microRNA (miR)-10a-5p, and according to quantitative polymerase chain reaction (q-PCR), miR-10a-5p was up-regulated in human glioma cells and negatively correlated with TUSC7 expression. Dual-luciferase reporter gene assay showed the ability of TUSC7 to bind to miR-10a-5p, and overexpression of TUSC7 notably inhibited miR-10a-5p expression, restrained human glioma cell proliferation and migration, and regulated cell cycle and cyclin expression via the brain-derived neurotrophic factor/extracellular signal-regulated kinase (BDNF/ERK) pathway. The inhibitory effect of TUSC7 on miR-10a-5p was also verified by designing miR-10a-5p overexpression and knockdown panels for wound healing, Transwell and Western blotting assays. TUSC7 suppresses human glioma cell proliferation and migration by negatively modulating miR-10a-5p and inhibiting the BDNF/ERK pathway, thus acting as a tumor suppressor gene in human gliomas.

AKR1B1 Represses Glioma Cell Proliferation through p38 MAPK-Mediated Bcl-2/BAX/Caspase-3 Apoptotic Signaling Pathways.

This study aimed to investigate the regulatory role of Aldo-keto reductase family 1 member B1 (AKR1B1) in glioma cell proliferation through p38 MAPK activation to control Bcl-2/BAX/caspase-3 apoptosis signaling. AKR1B1 expression was quantified in normal human astrocytes, glioblastoma multiforme (GBM) cell lines, and normal tissues by using quantitative real-time polymerase chain reaction. The effects of AKR1B1 overexpression or knockdown and those of AKR1B1-induced p38 MAPK phosphorylation and a p38 MAPK inhibitor (SB203580) on glioma cell proliferation were determined using an MTT assay and Western blot, respectively. Furthermore, the AKR1B1 effect on BAX and Bcl-2 expression was examined in real-time by Western blot. A luminescence detection reagent was also utilized to identify the effect of AKR1B1 on caspase-3/7 activity. The early and late stages of AKR1B1-induced apoptosis were assessed by performing Annexin V-FITC/PI double-staining assays. AKR1B1 expression was significantly downregulated in glioma tissues and GBM cell lines (T98G and 8401). Glioma cell proliferation was inhibited by AKR1B1 overexpression but was slightly increased by AKR1B1 knockdown. Additionally, AKR1B1-induced p38 MAPK phosphorylation and SB203580 reversed AKR1B1's inhibitory effect on glioma cell proliferation. AKR1B1 overexpression also inhibited Bcl-2 expression but increased BAX expression, whereas treatment with SB203580 reversed this phenomenon. Furthermore, AKR1B1 induced caspase-3/7 activity. The induction of early and late apoptosis by AKR1B1 was confirmed using an Annexin V-FITC/PI double-staining assay. In conclusion, AKR1B1 regulated glioma cell proliferation through the involvement of p38 MAPK-induced BAX/Bcl-2/caspase-3 apoptosis signaling. Therefore, AKR1B1 may serve as a new therapeutic target for glioma therapy development.

Targeting GPR133 via miR-106a-5p inhibits the proliferation, invasion, migration and epithelial-mesenchymal transition (EMT) of glioma cells

Background: Glioma is the most common malignant brain tumor. GPR133 is a key factor in the progression of glioma. However, the role of GPR133 in glioma invasion and EMT and the microRNAs (miRNAs) associated with this pathway are still poorly understood.Objective: This study aims to elucidate the biological function of miR-106a-5p and GPR133 in glioma as well as the molecular mechanism of their interaction.Methods: The mRNA expression of miR-106a-5p and GPR133 in glioma specimens and cells was analyzed by quantitative real-time polymerase chain reaction (qRT–PCR). The protein level of GPR133 and the levels of invasion- and EMT-related proteins were measured by western blotting. miR-106a-5p and GPR133 function in glioma cells was determined through cell counting kit-8 (CCK-8), transwell, wound healing, colony formation assays in vitro and xenograft assays in vivo. To determine the targeting relationship between miR-106a-5p and GPR133, a dual-luciferase reporter assay was conducted.Results: A marked reduction in miR-106a-5p expression was observed in glioma cells and specimens. Patients with high expression of miR-106a-5p had a good prognosis, while patients with high expression of GPR133 had a shorter OS. Additionally, overexpression of miR-106a-5p or downregulation of GPR133 inhibited the progression of glioma cells. Furthermore, miR-106a-5p negatively regulated GPR133 expression by binding to its 3′-UTR, and restrained the invasion, migration, proliferation and EMT of glioma cells by targeting GPR133.Conclusions: miR-106a-5p is a tumor suppressor that negatively regulates GPR133. The miR-106a-5p/GPR133 axis could potentially serve as a therapeutic target for glioma.

Polyphyllin I induces apoptosis and autophagy in temozolomide-resistant glioma via modulation of NRF2 and MAPK-signaling activation

ABSTRACT Glioma is the most prevailing main malignant neoplasm of the central nervous system with a miserable prognosis. Temozolomide is the first-line chemotherapy drug for glioma, but its drug resistance reduces temozolomide’s clinical efficacy and becomes the principal cause of the failure of glioma chemotherapy. Polyphyllin I (PPI), an active component in Rhizoma Paridis, demonstrates favorable therapeutic actions in diverse malignant neoplasms. Its effect on temozolomide-resistant glioma, however, has not yet been characterized. Here, we demonstrated that polyphyllin I inhibited the proliferation of temozolomide-resistant glioma cell in a concentration-dependent manner. Further, we found that polyphyllin I had a direct effect on temozolomide-resistant glioma tumor cells and promote reactive oxygen species (ROS)-dependent apoptosis and autophagy via mitogen-activated protein kinase (MAPK)-signaling (p38-JNK) pathway. Mechanistically, we showed that polyphyllin I downregulate the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway, indicating that polyphyllin I may be an expected therapeutic strategy for patients with temozolomide-resistant gliomas.

Down-Regulation of CEND1 Expression Contributes to The Progression and Temozolomide Resistance of Glioma.

This study was conducted to clarify the expression characteristics of cell cycle exit and neuronal differentiation 1 (CEND1) in glioma and its effects on the proliferation, migration, invasion, and resistance to temozolomide (TMZ) of glioma cells. In this experimental study, CEND1 expression in glioma tissues and its relationship with patients' survival were analyzed through bioinformatics. Quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry were performed to detect CEND1 expression in glioma tissues. The cell counting kit-8 (CCK-8) method was adopted to detect cell viability and the effects of different concentrations of TMZ on the inhibition rate of glioma cell proliferation, and the median inhibitory concentration of TMZ (IC50 value) was calculated. 5-Bromo- 2'-deoxyuridine (BrdU), wound healing and Transwell assays were performed to evaluate the impacts of CEND1 on glioma cell proliferation, migration, and invasion. Besides, the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Gene Ontology (GO) analysis, and Gene Set Enrichment Analysis (GSEA) were applied to predict the pathways regulated by CEND1. Nuclear factor-kappa B p65 (NF-κB p65) and phospho-p65 (p-p65) expression were detected by Western blot. CEND1 expression was reduced in glioma tissues and cells, and its low expression was significantly associated with the shorter survival of glioma patients. CEND1 knockdown promoted glioma cell growth, migration, and invasion, and increased the IC50 value of TMZ, whereas up-regulating CEND1 expression worked oppositely. Genes co-expressed with CEND1 were enriched in the NF-κB pathway, and knocking down CEND1 facilitated p-p65 expression, while CEND1 overexpression suppressed p-p65 expression. CEND1 inhibits glioma cell proliferation, migration, invasion, and resistance to TMZ by inhibiting the NF- κB pathway.

Systematic pan-cancer analysis identifies SLC35C1 as an immunological and prognostic biomarker

GDP-amylose transporter protein 1 (SLC35C1) plays an important role in many types of cancer. Therefore, it is clinically important to further investigate the expression profile of SLC35C1 in human tumors to provide new molecular clues for the pathogenesis of glioma. In this study, we performed a comprehensive pan-cancer analysis of SLC35C1 using a series of bioinformatics approaches and validated its differential tissue expression and biological function. The results showed that SLC35C1 was aberrantly expressed in different types of tumors and significantly correlated with overall survival (OS) and progression-free interval (PFI). More importantly, the expression level of SLC35C1 was closely correlated with Tumor Microenvironment (TME), immune infiltration and immune-related genes. In addition, we found that SLC35C1 expression was also closely related to Tumor Mutation Burden (TMB), Microsatellite Instability (MSI) and antitumor drug sensitivity in various cancer types. Functional bioinformatics analysis indicated that SLC35C1 may be involved in multiple signaling pathways and biological processes in glioma. Based on SLC35C1 expression, a risk factor model was found to predict OS of glioma. In addition, in vitro experiments showed that SLC35C1 knockdown significantly inhibited the proliferation, migration and invasive ability of glioma cells, while SLC35C1 overexpression promoted proliferation, migration, invasion and colony formation of glioma cells. Finally, quantitative real-time PCR confirmed that SLC35C1 was highly expressed in gliomas.

The PODNL1/AKT/β-catenin signaling axis mediates glioma progression and sensitivity to temozolomide

Abnormal expression of small leucine-rich repeat proteins (SLRP) in tumor tissues has been reported as a critical trigger for tumorigenesis and progression. However, the molecular mechanism of PODNL1, a novel member of SLRP family, in glioma remains largely unknown. Therefore, this study aimed to investigate its correlation with clinical factors by glioma cohort and to identify the molecular mechanisms of aberrant PODNL1 gene expression in glioma. Our findings revealed that both PODNL1 mRNA and protein levels were markedly upregulated in glioma tissues, and high PODNL1 mRNA level was significantly associated with poor prognosis of glioma patients. In functional assays, PODNL1 knockdown significantly suppressed the proliferation and invasion abilities of glioma cells, while overexpression of PODNL1 had the opposite effect both in vitro and in vivo. Mechanistically, PODNL1 knockdown suppressed the activation of AKT/mTOR signaling and inhibited nuclear translocation of β-catenin protein in the glioma cells. Our results suggest that PODNL1 acts as an oncogenic factor in glioma by promoting glioma progression through the activation of the kinase AKT, which indeces β-catenin nuclear translocation. Additionally, PODNL1 knockdown enhanced the sensitivity of glioma cells to temozolomide, a chemotherapeutic agent commonly used in the treatment of glioma. The PODNL1/AKT/β-catenin signaling axis represents a new potential therapeutic target against glioma. Furthermore, our data showed the combination of temozolomide and MK-2206, an AKT inhibitor, had a synergistic antitumor effect against glioma cells.

462 RNA-Based Therapeutics Targeting the Oncogenic Splicing Factor TRA2β Rewire Glioblastoma Cell Transcriptomes and Inhibit Their Proliferation

INTRODUCTION: Glioblastomas are an aggressive brain tumor that, despite current treatment paradigms, carry a poor prognosis. Novel therapies aimed at specific glioblastoma alterations are needed. Alternative RNA splicing is a critical step in gene expression that allows a single gene to encode multiple RNA and subsequently protein isoforms. Alternative splicing becomes dysregulated in human tumors, including glioblastoma, through alterations in upstream regulatory splicing factor proteins such as TRA2β, an oncogene that enhances glioma cell proliferation. Despite these known alterations, targeting alternative splicing in glioblastomas has not been leveraged therapeutically. METHODS: U87MG glioblastoma cells were treated with splice-switching antisense oligonucleotides (ASOs) targeting the TRA2β transcript (ASO-1570) or non-targeting control (ASO-CTL). Cancer-relevant phenotypes, including proliferation and apoptosis, were measured using high-content imaging. Transcriptomic splicing signatures were defined using high-depth RNA-sequencing with computational tools that quantify percent splicing event inclusion (PSI) and validated using RT-PCR and western blotting. RESULTS: ASO-1570 treatment increased inclusion of a poison-exon in TRA2β leading to decreased coding transcripts and subsequent reductions in TRA2β protein expression compared to ASO-CTL. ASO-1570 significantly decreased cell proliferation and increased apoptosis. Mechanistically, ASO-1570 treated cells exhibited significant differences in alternatively spliced events, impacting genes involved in cancer-relevant pathways such as p53 and mTOR signaling. For example, ASO-1570 led to increased exon skipping in MDM2 leading to decreased MDM2 protein expression and increased p53 wild-type expression. ASO-1570 treatment also impacted growth of U87MG 3D-neurospheres, suggesting efficacy in advanced models that better capture in vivo conditions. CONCLUSIONS: Glioblastoma cells are sensitive to ASO-mediated TRA2β knockdown, which mechanistically induced transcriptome wide changes that impact cancer-related pathways. Further testing of this ASO in vivo may open novel avenues for its use as a targeted glioblastoma therapeutic.

Integrative analysis of a novel super-enhancer-associated lncRNA prognostic signature and identifying LINC00945 in aggravating glioma progression

BackgroundSuper-enhancers (SEs), driving high-level expression of genes with tumor-promoting functions, have been investigated recently. However, the roles of super-enhancer-associated lncRNAs (SE-lncRNAs) in tumors remain undetermined, especially in gliomas. We here established a SE-lncRNAs expression-based prognostic signature to choose the effective treatment of glioma and identify a novel therapeutic target.MethodsCombined analysis of RNA sequencing (RNA-seq) data and ChIP sequencing (ChIP-seq) data of glioma patient-derived glioma stem cells (GSCs) screened SE-lncRNAs. Chinese Glioma Genome Atlas (CGGA) and The Cancer Genome Atlas (TCGA) datasets served to construct and validate SE-lncRNA prognostic signature. The immune profiles and potential immuno- and chemotherapies response prediction value of the signature were also explored. Moreover, we verified the epigenetic activation mechanism of LINC00945 via the ChIP assay, and its effect on glioma was determined by performing the functional assay and a mouse xenograft model.Results6 SE-lncRNAs were obtained and identified three subgroups of glioma patients with different prognostic and clinical features. A risk signature was further constructed and demonstrated to be an independent prognostic factor. The high-risk group exhibited an immunosuppressive microenvironment and was higher enrichment of M2 macrophage, regulatory T cells (Tregs), and Cancer-associated fibroblasts (CAFs). Patients in the high-risk group were better candidates for immunotherapy and chemotherapeutics. The SE of LINC00945 was further verified via ChIP assay. Mechanistically, BRD4 may mediate epigenetic activation of LINC00945. Additionally, overexpression of LINC00945 promoted glioma cell proliferation, EMT, migration, and invasion in vitro and xenograft tumor formation in vivo.ConclusionOur study constructed the first prognostic SE-lncRNA signature with the ability to optimize the choice of patients receiving immuno- and chemotherapies and provided a potential therapeutic target for glioma.

Deciphering the role of QPCTL in glioma progression and cancer immunotherapy.

Glioma is the most lethal and most aggressive brain cancer, and currently there is no effective treatment. Cancer immunotherapy is an advanced therapy by manipulating immune cells to attack cancer cells and it has been studied a lot in glioma treatment. Targeting the immune checkpoint CD47 or blocking the CD47-SIRPα axis can effectively eliminate glioma cancer cells but also brings side effects such as anemia. Glutaminyl-peptide cyclotransferase-like protein (QPCTL) catalyzes the pyroglutamylation of CD47 and is crucial for the binding between CD47 and SIRPα. Further study found that loss of intracellular QPCTL limits chemokine function and reshapes myeloid infiltration to augment tumor immunity. However, the role of QPCTL in glioma and the relationship between its expression and clinical outcomes remains unclear. Deciphering the role of QPCTL in glioma will provide a promising therapy for glioma cancer immunotherapy. QPCTL expression in glioma tissues and normal adjacent tissues was primarily analyzed in The Cancer Genome Atlas (TCGA) database, and further validated in another independent cohort from the Gene Expression Omnibus (GEO) database, Chinese Glioma Genome Atlas (CGGA), and Human Protein Atlas (HPA). The relationships between QPCTL expression and clinicopathologic parameters and overall survival (OS) were assessed using multivariate methods and Kaplan-Meier survival curves. And the proteins network with which QPCTL interacted was built using the online STRING website. Meanwhile, we use Tumor Immune Estimation Resource (TIMER) and Gene Expression Profiling Interactive Analysis (GEPIA) databases to investigate the relationships between QPCTL expression and infiltrated immune cells and their corresponding gene marker sets. We analyzed the Differentially Expressed Genes (DEGs) including GO/KEGG and Gene Set Enrichment Analysis (GSEA) based on QPCTL-high and -low expression tumors. In contrast to normal tissue, QPCTL expression was higher in glioma tumor tissue (p < 0.05). Higher QPCTL expression was closely associated with high-grade malignancy and advanced tumor stage. Univariate and multivariate analysis indicated the overall survival of glioma patients with higher QPCTL expression is shorter than those with lower QPCTL expression (p < 0.05). Glioma with QPCTL deficiency presented the paucity of infiltrated immune cells and their matching marker sets. Moreover, QPCTL is essential for glioma cell proliferation and tumor growth and is a positive correlation with glioma cell stemness. High QPCTL expression predicts high grades of gliomas and poor prognosis with impaired infiltration of adaptive immune cells in the tumor microenvironment as well as higher cancer stemness. Moreover, targeting QPCTL will be a promising immunotherapy in glioma cancer treatment.

MAPK9 is Correlated with a Poor Prognosis and Tumor Progression in Glioma

Glioma has a high incidence in young and middle-aged adults and a poor prognosis. Because of late diagnosis and uncontrollable recurrence of the primary tumor after failure of existing treatments, glioma patients tend to have a poor prognosis. Recent advances in research have revealed that gliomas exhibit unique genetic features. Mitogen-activated protein kinase 9 (MAPK9) is significantly upregulated in mesenchymal glioma spheres and may be a new target for glioma diagnosis. This study aimed to investigate the potential diagnostic significance and predictive value of MAPK9 in glioma. Paraffin-embedded tumor tissues and paracancerous tissues were collected from 150 glioma patients seen at the General Hospital of Northern Theater Command. Immunohistochemistry and western blot assays were used to detect the expression levels of MAPK9. Prognosis and survival analyses were performed using SPSS 26 software for univariate/multivariate analysis and log-rank analysis. Cellular models were used to assess the effect of MAPK9 overexpression and knockdown in vitro. MAPK9 expression was higher in glioma tissues than in paraneoplastic tissues. Prognostic and survival analyses revealed that the MAPK9 expression level is an independent prognostic factor in glioma patients. In addition, overexpression of MAPK9 significantly promoted the proliferation and migration of primary glioma cells, possibly via the Wnt/β-catenin-regulated EMT pathway. MAPK9 is an independent prognostic factor in glioma and is involved in tumor progression.

CRNDE, an enhancer RNA of prognostic value in glioma, correlates with immune infiltration: A pan-cancer analysis

Background: Recent evidence has emerged regarding the modification of the relationship between the enhancer RNA (eRNA) colorectal neoplasia differentially expressed (CRNDE) and the prognosis of patients with cancer. Nevertheless, the role of CRNDE in pan-cancer and tumour immune microenvironment (TIME) remains largely unexplored. Methods: Multiple bioinformatic methods were employed to unravel the role of elncRNA CRNDE in a wide range of cancers from the perspective of the expression patterns, prognosis, tumour immunity, and the association between CRNDE and its target gene IRX5 based on the public database. A nomogram was created by integrating independent factors. Gene set enrichment analysis (GSEA) was used to determine the potential signalling pathway mechanisms. Molecular biology experiments including RT-qPCR, MTT, Transwell, and wound-healing analyses were performed to evaluate the proliferation, migration, and invasion of glioma cells. Finally, RT-qPCR and immunohistochemistry were performed to analyse the expression and function of CRNDE in gliomas of different grades. Nissl staining was used to evaluate the potential effects of CRNDE knockdown in glioblastoma tissues. Results: CRNDE was dysregulated and associated with clinical features in 15 of the 33 cancer types. The survival analysis showed that high CRNDE expression might lead to a worsened prognosis among the six cancer types. CRNDE might be involved in immune regulation in multiple cancer types. CRNDE correlated with multiple tumours and immune-related pathways. Additionally, CRNDE knockdown inhibited glioma cell proliferation, migration, and invasion. Nissl staining confirmed that CRNDE siRNA notably decreased tumour growth. A stronger correlation between immune cells and CRNDE/IRX5 in lower-grade glioma than in glioblastoma multiforme tissues, and an association with IRX5 and immune checkpoint gene NRP1 were observed. Conclusions: An Enhancer RNA CRNDE may serve as a biomarker for cancer immunologic infiltration and poor prognosis, providing a new approach for cancer treatment.

Biomimetic three-dimensional glioma model printed in vitro for the studies of glioma cells and neurons interactions.

1The interactions between glioma cells and neurons are important for glioma progression but are rarely mimicked and recapitulated in in vitro three-dimensional (3D) models, which may affect the success rate of relevant drug research and development. In this study, an in vitro bioprinted 3D glioma model consisting of an outer hemispherical shell with neurons and an inner hemisphere with glioma cells is proposed to simulate the natural glioma. This model was produced by extrusion-based 3D bioprinting technology. The cells survival rate, morphology, and intercellular Ca2+ concentration studies were carried out up to 5 days of culturing. It was found that neurons could promote the proliferation of glioma cells around them, associate the morphological changes of glioma cells to be neuron-like, and increase the expression of intracellular Ca2+ of glioma cells. Conversely, the presence of glioma cells could maintain the neuronal survival rate and promote the neurite outgrowth. The results indicated that glioma cells and neurons facilitated each other implying a symbiotic pattern established between two types of cells during the early stage of glioma development, which were seldom found in the present artificial glioma models. The proposed bioprinted glioma model can mimic the natural microenvironment of glioma tissue, provide an in-depth understanding of cell-cell interactions, and enable pathological and pharmacological studies of glioma.

Phosducin-like 3 is a novel prognostic and onco-immunological biomarker in glioma: A multi-omics analysis with experimental verification.

Malignant glioma is the most frequent primary tumor of the central nervous system. PDCL3 is a member of the phosducin-like protein family, and its imbalance has been shown to be associated with several human diseases. However, the underlying role of PDCL3 in human malignant cancers, especially in malignant gliomas, is unclear. In this study, we combined public database analysis and experimental verification to explore the differential expression, prognostic value and potential functions and mechanisms of PDCL3. The results revealed that PDCL3 is upregulated in multiple cancers and acts as a potential prognostic biomarker of glioma. Mechanistically, PDCL3 expression is associated with epigenetic modifications and genetic mutations. PDCL3 may directly interact with the chaperonin-containing TCP1 complex, regulating cell malignancy, cell communication and the extracellular matrix. More importantly, the association of PDCL3 with the infiltration of immune cells, immunomodulatory genes, immune checkpoints, cancer stemness and angiogenesis suggested that PDCL3 may regulate the glioma immune landscape. Furthermore, PDCL3 interference also decreased the proliferation, invasion and migration of glioma cells. In conclusion, PDCL3 is a novel oncogene and can be adopted as a biomarker with value in assisting clinical diagnosis, predicting patient outcomes and assessing the immune landscape of the tumor microenvironment in glioma.

Immunological and tumor-intrinsic mechanisms mediate the synergistic growth suppression of experimental glioblastoma by radiotherapy and MET inhibition

The hepatocyte growth factor (HGF)/MET signaling pathway has been proposed to be involved in the resistance to radiotherapy of glioblastoma via proinvasive and DNA damage response pathways.Here we assessed the role of the MET pathway in the response to radiotherapy in vitro and in vivo in syngeneic mouse glioma models. We find that the murine glioma cell lines GL-261, SMA-497, SMA-540 and SMA-560 express HGF and its receptor MET and respond to exogenous HGF with MET phosphorylation. Glioma cell viability or proliferation are unaffected by genetic or pharmacological MET inhibition using tepotinib or CRISPR/Cas9-engineered Met gene knockout and MET inhibition fails to sensitize glioma cells to irradiation in vitro. In contrast, the combination of tepotinib with radiotherapy prolongs survival of orthotopic SMA-560 or GL-261 glioma-bearing mice compared with radiotherapy or tepotinib treatment alone. Synergy is lost when such experiments are conducted in immunodeficient Rag1−/− mice, and, importantly, also when Met gene expression is disrupted in the tumor cells. Combination therapy suppresses a set of pro-inflammatory mediators including matrix metalloproteases that are upregulated by radiotherapy alone and that have been linked to poor outcome in glioblastoma. Several of these mediators are positively regulated by transforming growth factor (TGF)-β, and pSMAD2 levels as a surrogate marker of TGF-β pathway activity are suppressed by combination treatment. We conclude that synergistic suppression of experimental syngeneic glioma growth by irradiation and MET inhibition requires MET expression in the tumor as well as an intact immune system. Clinical evaluation of this combined strategy in newly diagnosed glioblastoma is warranted.

OLFML3, as a potential predictor of prognosis and therapeutic target for glioma, is closely related to immune cell infiltration

AbstractThe low response rate to immunosuppressant is mainly due to the lack of adequate knowledge about the tumor microenvironment (TME) and screening biomarkers for gliomas. We aimed to identify the promising immune biomarkers and new immune classification of glioma. In this study, multiple‐immune algorithms were used to calculate immune‐infiltration scores. Unsupervised and supervised machine learning methods were used to perform the classification. We observed that OLFML3 overexpression was indicated in gliomas and linked to poor prognosis. OLFML3 knockdown inhibited proliferation, invasion and increased the sensitivity of glioma cells to temozolomide. OLFML3 expression could also reflect the aberrant immune status. Based on the immune‐related signature, patients were divided into three immune subtypes via consensus clustering. Patients with C2 subtype presented poorer prognosis and shorter progression free survival than patients with other two subtypes. The TME patterns among subtypes were different. C2 and C3 subtypes are the immune‐inflamed and immune‐desert tumors, respectively. Additionally, compared with C3 subtype, patients with C1/C2 subtypes were more likely to respond to immunotherapy. The pRRophetic algorithm indicated patients with C1/C2 subtypes were more resistant to temozolomide, but sensitive to paclitaxel and cisplatin. To conclude, OLFML3 overexpression affects glioma cell proliferation, invasion, and TMZ sensitivity and has been proved to be an independent prognostic‐ and immune‐related biomarker. Additionally, the novel immune subtype's classification could provide the prognostic and predictive predictors for glioma patients and may guide physicians in selecting potential responders.