Biological Functions Of Glioma Cells Research Articles

Glucose regulates the HMGB1 signaling pathway through SIRT1 in glioma

BackgroundGlucose is a fundamental substance for numerous cancers, including glioma. However, its influence on tumor cells regulatory mechanisms remains uncertain. SIRT1 is a regulator of deacetylation and a key player in the progression of malignant tumors. The objective of this study was to examine the role of glucose and SIRT1 in glioma. MethodsThis study investigated the association of SIRT1 expression with clinicopathological features and prognosis in glioma patients using the TCGA database. The Western blotting technique was used to identify the expression of SIRT1 protein in glioma cells. The study also examined the impact of differing glucose concentrations on the biological functions of glioma cells. The study investigated the expression of SIRT1 and HMGB1 signaling pathways in glioma. Additionally, resilience experiments were conducted utilizing SRT1720. ResultsSIRT1 is a gene that suppresses tumors and is low expressed in gliomas. Low expression of this gene is strongly linked to a poor prognosis in patients with glioma. High concentrations of glucose can promote the proliferation, migration, and invasion of glioma cells, while also inhibiting apoptosis. The findings of this mechanistic study provide evidence that glucose can down-regulate SIRT1 expression, leading to increased levels of acetylated HMGB1. This in turn promotes the ex-nuclear activation of HMGB1 and associated signaling pathways, ultimately driving glioma malignancy. ConclusionGlucose has the ability to regulate the HMGB1 associated signaling pathway through SIRT1, thus promoting glioma progression. This holds significant research value.

MiR-381-3p Involves in Glioma Progression by Suppressing Tumor-Promoter Factor ANTXR1.

Accumulating studies revealed association between development of glioma and miRNA dysregulation. A case in point is miR-381-3p, but its mechanism in glioma is unclear yet. In this work, we confirmed that overexpressed miR-381-3p repressed biological functions of glioma cells. Additionally, we also discovered that upregulated anthrax toxin receptor 1 (ANTXR1) was negatively mediated by miR-381-3p. We further proved that miR-381-3p-targeted ANTXR1 was able to counteract the suppression of miR-381-3p on biological functions of glioma. We concluded that miR-381-3p and ANTXR1 were both important factors in modulating glioma progression. miR-381-3p/ANTXR1 axis is expected to be a molecular target for glioma.

RNF144A-AS1 promotes the development of glioma cells by targeting miR-665/HMGA1 axis

PurposeGlioma is a malignant tumor in the central nervous system. Long non-coding RNA (lncRNA) RNF144A-AS1 exerts a regulatory effect in cancers, but its role in glioma remains obscure and needs to be further study. MethodsExpressions of RNF144A-AS1, miR-665 and High-mobility group A1 (HMGA1) in glioma tissues and/or cells were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The relationship between miR-665 and RNF144A-AS1/HMGA1 was determined by bioinformatics and Dual-Luciferase Reporter assay. The effect of RNF144A-AS1 on the biological functions of glioma cells was confirmed by loss and gain experiments (including cell counting kit 8, clone formation, wound healing, Transwell, qRT-PCR and western blot). The regulatory mechanism of RNF144A-AS1/miR-665/HMGA1 axis on glioma was confirmed by rescue experiments. ResultsRNF144A-AS1 and HMGA1 were high-expressed in gliomas, and miR-665 was low-expressed in gliomas, which led to the increase of glioma cell viability, proliferation, migration and invasion ability and insufficient apoptosis ability. Overexpression of RNF144A-AS1 suppressed the expressions of Bax and cleaved caspase-3, and promoted Bcl-2 expression. RNF144A-AS1 up-regulated the expression of HMGA1 by targeting miR-665, thereby promoting the development of glioma cells. ConclusionRNF144A-AS1/miR-665/HMGA1 axis implicated in the development of glioma.

The Inhibitory Effect of miR-345 on Glioma Progression Is Closely Related to circRNA-hsa_circ_0073237 and HDGF

Glioma is the most common primary malignant tumor of the central nervous system and has a poor prognosis. Therefore, exploring the key molecular targets is a new opportunity for basic research and clinical treatment of glioma. Previous studies found that circRNA-hsa_circ_0073237 was upregulated in gliomas. Our further analyses of the biological function and molecular mechanism of hsa_circ_0073237 showed that hsa_circ_0073237 was also upregulated in glioma cell lines and could combine with miR-345 to inhibit its expression. miR-345 was downregulated in glioma tissues and cells, and targeted to regulate the expression of hepatoma-derived growth factor (HDGF), while HDGF expression was enhanced in glioma. Hsa_circ_0073237 promoted the expression of HDGF in glioma cells by adsorbing miR-345. Hsa_circ_0073237 siRNA, miR-345, and HDGF siRNA effectively inhibited cell viability and invasion and promoted cell apoptosis. When expression of hsa_circ_0073237 and miR-345 was inhibited simultaneously, cell viability, apoptosis, and invasion did not change significantly; however, after transfection with HDGF overexpression vector, the effects of hsa_circ_0073237 siRNA and miR-345 on glioma cell viability, apoptosis, and invasion were obviously reversed. Further construction of glioma xenograft models in nude mice confirmed that the introduction of miR-345 in vivo effectively inhibited tumor growth, significantly reduced tumor diameter and weight, and obviously decreased the expression of HDGF. Therefore, hsa_circ_0073237 can regulate the biological functions of glioma cells through miR-345/HDGF, thereby affecting the progression of tumors, indicating that the hsa_circ_0073237/miR-345/HDGF pathway may be a key target for the treatment of glioma.

M2 bone marrow-derived macrophage-derived exosomes shuffle microRNA-21 to accelerate immune escape of glioma by modulating PEG3

BackgroundGrowing studies have focused on the role of microRNA-21 (miR-21) in glioma, thus our objective was to discuss the effect of M2 bone marrow-derived macrophage (BMDM)-derived exosomes (BMDM-Exos) shuffle miR-21 on biological functions of glioma cells by regulating paternally expressed gene 3 (PEG3).MethodsSeventy-one cases of human glioma tissues and 30 cases of non-tumor normal brain tissues were collected and stored in liquid nitrogen. PEG3 and miR-21 expression in glioma tissues was tested. The fasting venous blood of glioma patients and healthy control was collected and centrifuged, and then the supernatant was stored at − 80 °C refrigerator. The contents of interferon (IFN)-γ and transforming growth factor-β1 (TGF-β1) in serum were tested by ELISA. Glioma cells and normal glial cells were cultured to screen the target cells for further in vitro experiments. BMDM-Exos was obtained by ultra-high speed centrifugation and then was identified. BMDM-Exos was co-cultured with U87 cells to detect the biological functions. The fasting venous blood of glioma patients was extracted and treated with ethylene diamine tetraacetic acid-K2 anti-freezing, and then CD8+T cells were isolated. CD8+T cells were co-cultured with U87 cells to detect the CD8+T proliferation, cell cytotoxic activity, U87 cell activity, as well as IFN-γ and TGF-β1 levels. Moreover, BALB/c-nu/nu mice was taken, and the human-nude mouse glioma orthotopic transplantation model was established with U87 cells, and then mice were grouped to test the trends in tumor growth. The brain of mice (fixed by 10% formaldehyde) was sliced to detect the expression of Ki67 and proliferating cell nuclear antigen (PCNA). The spleen of mice was taken to prepare single-cell suspension, and the percentage of T lymphocytes in spleen to CD8+T cells was detected.ResultsPEG3 expression was decreased and miR-21 expression was increased in glioma cells and tissues. Depleting miR-21 or restoring PEG3 suppressed growth, migration and invasion as well as accelerated apoptosis of glioma cells, also raised CD8+T proliferation, cell cytotoxic activity, and IFN-γ level as well as decreased U87 cell activity and TGF-β1 level. BMDM-Exos shuttle miR-21 promoted migration, proliferation and invasion as well as suppressed apoptosis of glioma cells by reducing PEG3. Exosomes enhanced the volume of tumor, Ki67 and PCNA expression, reduced the percentage of CD8+T cells in glioma mice.ConclusionBMDM-Exos shuffle miR-21 to facilitate invasion, proliferation and migration as well as inhibit apoptosis of glioma cells via inhibiting PEG3, furthermore, promoting immune escape of glioma cells.

Circ-DONSON promotes malignant progression of glioma through modulating FOXO3.

The aim of this study was to investigate the expression level of circ-DONSON in glioma and to explore its effect on glioma metastasis and the underlying mechanism. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine circ-DONSON expression in 40 paired glioma tumor tissues and adjacent tissues. Meanwhile, the relation between circ-DONSON level and clinical parameters of glioma and the prognosis of patients was analyzed. The expression of circ-DONSON in glioma cell lines was analyzed by qRT-PCR as well. In addition, circs-DONSON silencing model was constructed in glioma cell lines. Cell counting kit-8 (CCK-8), cell scratch, and transwell migration assays were performed to investigate the effect of circ-DONSON on biological functions of glioma cells. Finally, the interplay between FOXO3 and circ-DONSON was explored. QRT-PCR results revealed that the expression level of circ-DONSON in glioma tumor tissues was remarkably higher than that of adjacent tissues, and the difference was statistically significant (p<0.05). Compared with patients with low expression of circ-DONSON, significantly higher prevalence of lymph node or distant metastasis and worse prognosis were observed in patients with high expression of circ-DONSON (p<0.05). The proliferation and migration abilities of glioma cells in circ-DONSON silenced group were remarkably suppressed when compared with NC group (p<0.05). Additionally, FOXO3 expression was remarkably down-regulated in glioma cell lines and tissues. FOXO3 expression was negatively correlated with circ-DONSON expression. In addition, cell reverse experiment demonstrated that circ-DONSON and FOXO3 can regulate each other, thereby together affecting the malignant progression of glioma. Circ-DONSON was remarkably associated with lymph node or distant metastasis, as well as poor prognosis of patients with glioma. Furthermore, it promoted the metastasis of glioma cells via regulating FOXO3.

FoxD2-AS1 promotes glioma progression by regulating miR-185-5P/HMGA2 axis and PI3K/AKT signaling pathway.

Background/Aims: The present study was aimed at exploring the role of long noncoding RNA (lncRNA) FOXD2-AS1 in the development and progression of glioma and the underlying mechanism of FOXD2-AS1/miR-185-5p/HMGA2 network in glioma via regulation of PI3K/Akt signaling pathway.Methods: Microarray analysis was used for preliminary screening for candidate lncRNAs and mRNAs in glioma tissues. qRT-PCR and Western blot were used to determine the expression of FOXD2-AS1. The potential effects of FOXD2-AS1 on the viability, mobility and apoptosis of glioma cells were evaluated using MTT assay, Transwell assays and flow cytometry. The xenograft tumor model was performed to examine the influence of the lncRNA FOXD2-AS1/miR-185-5p/HMGA2 network on the biological functions of glioma cells. Luciferase assay and immunoprecipitation assay were examined to dissect molecular mechanisms.Results: LncRNA FOXD2-AS1 was overexpressed in human glioma, and upregulated FOXD2-AS11 expression indicated higher WHO grade (p < 0.05). MiR-185-5p was downregulated, whereas HMGA2 was upregulated in glioma tissues in comparison with para-carcinoma tissues. FOXD2-AS1 could regulate the expression of HMGA2 via miR-185-5p. Knockdown of FOXD2-AS1 significantly inhibited proliferation and metastatic potential of glioma cells, whereas endogenous expression FOXD2-AS1 inhibited the glioma cell activity through targeting HMGA2.Conclusions: lncRNA FOXD2-AS1 acted as a sponge of miR-185-5p and influenced the PI3K/Akt signaling pathway through regulating HMGA2. LncRNA FOXD2-AS1 modulated HMGA2 and PI3K/Akt downstream signaling through sponging miR-185-5p, thereby promoting tumorigenesis and progression of glioma.

Long noncoding RNA nuclear enriched abundant transcript 1 impacts cell proliferation, invasion, and migration of glioma through regulating miR-139-5p/ CDK6.

We aimed to explore the impact of long noncoding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) on cell proliferation, invasion, and migration of glioma. Differentially expressed genes were screened out from Gene Expression Omnibus data set based on the microarray analysis. The expression levels of lncRNA NEAT1, miR-139-5p, and CDK6 in glioma cells and tissues were examined by quantitative reverse transcription polymerase chain reaction, and the protein level of CDK6 in glioma cells was determined by western blot and immunohistochemistry. Glioma cell viability, cell cycle, and apoptosis were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) and flow cytometry, respectively, whereas cell invasion and migration were analyzed by transwell assay. The target relationships among NEAT1, miR-139-5p, and CDK6 were confirmed by dual-luciferase reporter gene assay. The effects of lncRNA NEAT1 on tumor growth were further testified through glioma xenografts in nude mice. LncRNA NEAT1 and CDK6 were highly expressed in glioma tissues and cells, whereas miR-139-5p was lowly expressed. There were target relationships and correlations on expressions between miR-139-5p and NEAT1/ CDK6. NEAT1 and CDK6 could promote cell proliferation and metastasis of glioma cells and impeded cell apoptosis, whereas miR-139-5p exerted suppressive effects on the biological functions of glioma cells. NEAT1 regulated CDK6 to affect glioma growth through sponging miR-139-5p. LncRNA NEAT1 promotes cell proliferation, invasion, and migration of glioma through regulating miR-139-5p/CDK6 pathway.

RETRACTED: LncRNA PVT1 Facilitates Tumorigenesis and Progression of Glioma via Regulation of MiR-128-3p/GREM1 Axis and BMP Signaling Pathway

The current research was aimed at probing into the role of long noncoding RNA (lncRNA) PVT1 in the pathogenesis of glioma and the regulatory mechanism of PVT1/miR-128-3p/GREM1 network in glioma via regulation of the bone morphogenetic protein (BMP) signaling pathway. Microarray analysis was used for preliminary screening for candidate lncRNAs and mRNAs in glioma tissues. Real-time quantitative polymerase chain reaction, Western blot, MTT assay, flow cytometry, migration and invasion assays, and xenograft tumor model were utilized to examine the influence of the lncRNA PVT1/miR-128-3p/GREM1 network on the biological functions of glioma cells. Luciferase assay and RNA-binding protein immunoprecipitation assay were used to validate the miR-128-3p-target relationships with lncRNA PVT1 or GREM1. In addition, the impact of GREM1 on BMP signaling pathway downstream proteins BMP2 and BMP4 was detected via Western blot. LncRNA PVT1 was highly expressed in human glioma tissues and significantly associated with WHO grade (I-II vs III-IV; p < 0.05). There existed a regulatory relationship between lncRNA PVT1 and miR-128-3p as well as that between miR-128-3p and GREM1. MiR-128-3p was downregulated, whereas GREM1 was upregulated in glioma tissues in comparison with para-carcinoma tissues. Overexpression of GREM1 promoted the proliferation and metastatic potential of glioma cells, whereas miR-128-3p mimics inhibited the glioma cell activity through targeting GREM1. Furthermore, lncRNA PVT1 acted as a sponge of miR-128-3p and, thus, influenced the BMP signaling pathway downstream proteins BMP2 and BMP4 through regulating GREM1. LncRNA PVT1 modulated GREM1 and BMP downstream signaling proteins through sponging miR-128-3p, thereby promoting tumorigenesis and progression of glioma.

Ketohexokinase is involved in fructose utilization and promotes tumor progression in glioma

Many studies have pinpointed that fructose could be utilized as a carbon source in some cancers, and we also defined that glioma cells could utilize fructose to maintain themselves survival and proliferation depending on GLUT5 expression recently. However, ketohexokinase (KHK), as a key enzyme involved in fructose catabolism, drew less attention in cancers, especially in glioma. In the present study, we first analyzed the expression levels of KHK in glioma tissues and the correlations of KHK expression with clinicopathological variables of patients with glioma. Meanwhile, we detected the effect of silencing KHK on the biological functions of glioma cells in fructose medium. From the results, we found that KHK was expressed at significantly higher level in glioma tissues than in non-tumor brain, and KHK expression was significantly correlated with tumor malignancy and poor survival of glioma patients (p < 0.01). Functionally, knockdown of KHK could significantly inhibit cell proliferation and migration of glioma cells in fructose medium. Furthermore, we investigated the KHK expression level after long-time treatment with fructose, and detected the change of cell biological behaviour, then we found that the expression level of KHK was significantly increased and these cells showed more malignant properties. Taken together, our results suggest that high fructose diet and KHK overexpression are correlated with glioma malignant progression and patients' poor survival, and we believe this hypothesis would open the door for novel therapeutic agents and mentalities for glioma.

Effects of three-dimensional collagen scaffolds on the expression profiles and biological functions of glioma cells.

Three-dimensional (3D) culture has been increasingly used to investigate tumor cell biology for improved simulation of the natural developing environment. However, the way in which 3D culture affects the gene expression and biological functions of glioma cells remains to be fully elucidated. In the present study, 3D culture environments were established using collagen scaffolds with different pore sizes, followed by the comparison of gene expression profiles and associated biological functions of glioma cells, including the U87, U251 and HS683 cell lines, in 3D collagen scaffolds with conventional two-dimensional (2D) cultured cells. Finally, the possible signaling pathways regulating these differences were investigated. It was found that the 3D collagen scaffold culture upregulated the expression of genes associated with stemness, cell cycle, apoptosis, epithelia-mesenchymal transition, migration, invasion and glioma malignancy, and induced the corresponding functional changes. Apoptotic pathways, the Wnt pathway, Sonic Hedgehog pathway and Notch pathway, may be involved in the regulation of these changes. The aperture size of the collagen-scaffold did not appear to affect the gene expression or functions of the glioma cells. The results of the study suggested that the 3D collagen scaffold enhanced the malignancy of glioma cells and may be a promising in vitro platform for investigations of glioma.

High expression of VRK1 is related to poor prognosis in glioma

Vaccinia-related kinase 1 (VRK1) is a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases, which phosphorylates several transcription factors and has been postulated to be involved in regulation of cell proliferation. However, it remains unclear whether aberrant expression of VRK1 is related to the development of glioma. In this study, we aimed to investigate the clinical significance of VRK1 expression in human glioma and its biological function in glioma cells. Western blot and immunohistochemical analysis revealed that VRK1 was highly expressed in glioma tissues and cell lines. In addition, the expression level of VRK1 was positively correlated with glioma pathological grade, as well as Ki-67 expression. Kaplan-Meier analysis revealed that patients with high VRK1 expression was associated with a poorer prognosis. To determine whether VRK1 could regulate the proliferation of glioma cells, we transfected glioma cells with interfering RNA target VRK1, then investigated cell proliferation with cell counting kit (CCK) −8, flow cytometry assays and colony formation analyses. Our results indicated that knockdown of VRK1 would inhibit the proliferation of glioma cells. Besides, reduced expression of VRK1 could induce the apoptosis of glioma cells. On the basis of these findings, we suggested that VRK1 might be a promising prognostic biomarker of glioma.

Knockdown of DIXDC1 Inhibits the Proliferation and Migration of Human Glioma Cells.

DIX domain containing 1 (DIXDC1), the human homolog of coiled-coil-DIX1 (Ccd1), is a positive regulator of Wnt signaling pathway. Recently, it was found to act as a candidate oncogene in colon cancer, non-small-cell lung cancer, and gastric cancer. In this study, we aimed to investigate the clinical significance of DIXDC1 expression in human glioma and its biological function in glioma cells. Western blot and immunohistochemistry analysis showed that DIXDC1 was overexpressed in glioma tissues and glioma cell lines. The expression level of DIXDC1 was evidently linked to glioma pathological grade and Ki-67 expression. Kaplan-Meier curve showed that high expression of DIXDC1 may lead to poor outcome of glioma patients. Serum starvation and refeeding assay indicated that the expression of DIXDC1 was associated with cell cycle. To determine whether DIXDC1 could regulate the proliferation and migration of glioma cells, we transfected glioma cells with interfering RNA-targeting DIXDC1; investigated cell proliferation with Cell Counting Kit (CCK)-8, flow cytometry assays, and colony formation analyses; and investigated cell migration with wound healing assays and transwell assays. According to our data, knockdown of DIXDC1 significantly inhibited proliferation and migration of glioma cells. These data implied that DIXDC1 might participate in the development of glioma, suggesting that DIXDC1 can become a potential therapeutic strategy for glioma.

Upregulation of B23 promotes tumor cell proliferation and predicts poor prognosis in glioma

B23 (also known as Nucleophosmin, NPM, numatrin or NO38) is a ubiquitously expressed phosphoprotein belonging to the nucleoplasmin family of chaperones. In this study we intended to investigate the clinical significance of B23 expression in human glioma and its biological function in glioma cells. Western blot and immunohistochemistry analysis showed that B23 was overexpressed in glioma tissues and glioma cell lines. In addition, the expression level of B23 was positively correlated with glioma pathological grade and Ki-67 expression. Kaplan–Meier analysis revealed that a higher B23 expression in patients with glioma was associated with a poorer prognosis. In vitro, after the release of glioma cell lines from serum starvation, the expression of B23 was upregulated, as well as PCNA (Proliferating Cell Nuclear Antigen) and cyclin A. In addition, knockdown of B23 by small interfering RNA transfection diminished the expression of PCNA, cyclin D1 and arrested cell growth at G1 phase. Taken together, our results implied that B23 could be a candidate prognostic biomarker as well as a potential therapeutical target of glioma.

CHD1L Regulates Cell Cycle, Apoptosis, and Migration in Glioma.

Chromodomain helicase/ATPase DNA binding protein 1-like (CHD1L) gene is a newly identified oncogene located at Chr1q21 and it is amplified in many solid tumors. In this study, we intended to investigate the clinical significance of CHD1L expression in human glioma and its biological function in glioma cells. Western blot and immunohistochemistry analysis showed that CHD1L was overexpressed in glioma tissues and glioma cell lines. In addition, the expression level of CHD1L was positively correlated with glioma pathological grade and Ki-67 expression. Kaplan-Meier curve indicated that high expression of CHD1L may result in poor prognosis of glioma patients. Accordingly, suppression of CHD1L in glioma cells was shown to induce cell cycle arrest and increase apoptosis. In addition, knockdown of CHD1L significantly accelerated migration and invasion ability of glioma cells. Together our findings suggest that CHD1L is involved in the progression of glioma and may be a novel target for further therapy.

LAP3 promotes glioma progression by regulating proliferation, migration and invasion of glioma cells

Leucine aminopeptidase 3 (LAP3), belonging to the M1 family, has been proved to catalyze the hydrolysis of leucine residues. Leucine aminopeptidases are involved in many pathological disorders and regulate cell proliferation, invasion and/or angiogenesis of tumor. Recent study showed that LAP3 is highly expressed in several malignant and affects tumor angiogenesis. We aimed at investigating the clinical significance of LAP3 expression in human gliomas and its biological function in glioma cells. RT-PCR, Western blot and immunohistochemistry analysis were used to detect the expression levels of LAP3 in 121 glioma tissues, high LAP3 expression was correlated with the grade of malignancy and poor prognosis of glioma patients. In vitro, after increasing of LAP3 by myc-LAP3 transfection and knockdown of LAP3 by siRNA transfection in glioma cells, cell viability, cell cycle, migration and invasion were determined with CCK8 assay, flow cytometry, wound healing and transwell invasion assays. The results indicated that increasing LAP3 could promte cell viability, cell cycle, migration and invasion, knockdown LAP3 could decrease cell viability, suppress cell proliferation, migration and invasion. Our findings uncover that LAP3 might be a new prognostic factor and be close correlation with glioma cell growth, magration, invasion.