Normal Astrocyte Cells Research Articles

Interference of FZD2 suppresses proliferation, vasculogenic mimicry and stemness in glioma cells via blocking the Notch/NF‑κB signaling pathway.

Frizzled family protein 2 (FZD2) is widely associated with tumor development and metastasis. The present study aimed to gain an insight into the role and regulatory mechanism of FZD2 in glioma. The expression level of FZD2 in normal astrocyte and glioma cells was determined by reverse transcription-quantitative PCR and western blotting, and cell transfection was conducted for FZD2 expression knockdown. Malignant behaviors including cell proliferation, migration and invasion, vasculogenic mimicry (VM) and cell stemness were determined using Cell Counting Kit-8, 5-Ethynyl-2'-deoxyuridine (EdU) staining, colony formation, wound healing, Transwell, 3D culturing and sphere formation assays. The expression levels of proteins related to stemness, epithelial-mesenchymal transition (EMT) and Notch/NF-κB signaling were measured by western blotting. Then, the Notch agonist, Jagged-1 (JAG), was adopted for rescue experiments. The results demonstrated that FZD2 was highly expressed in glioma cells. Interference of FZD2 expression suppressed the proliferation of glioma cells, as evidenced by the reduced cell viability and the number of EdU+ cells and colonies. Meanwhile, the reduced sphere formation ability and decreased protein expression of Nanog, Sox2 and Oct4 following FZD2 knockdown confirmed that FZD2 repressed cell stemness in glioma. Additionally, FZD2 knockdown suppressed the migration, invasion, EMT and VM formation capabilities of glioma cells, and also blocked the Notch/NF-κB signaling pathway. Furthermore, activation of Notch by JAG treatment partially reversed the aforementioned FZD2 knockdown-mediated changes in glioma cell malignant behaviors. In conclusion, FZD2 may contribute to glioma progression through activating the Notch/NF-κB signaling pathway, providing a plausible therapeutic target for the treatment of glioma.

A novel fluorescence enhancement Al(III) sensor based on C1 symmetric Binol imine derivative: Recognition, binding mechanism and Bio-imaging application

A novel C1 symmetric Binol imine Schiff base fluorescence sensor (Sa,R)-6 was designed and synthesized by using (S)-Binol-3-aldehyde as initial material. The probe showed great fluorescence enhancement at λ = 552 nm and visual light yellow fluorescence under 365 nm UV lamp irradiation with presence of Al3+. Quantitative test was feasible from 10 μM to the detection limit which reaches nanomole level. Job’s plot, HRMS spectroscopic and NMR titration indicated the formation of Al[(Sa,R)-6]2+. DFT calculations suggested the coordination reaction lead to a CHEF effect and the “turn-on” fluorescence response. Moreover, (Sa,R)-6 was well tolerable to human normal astrocyte cell line HA-1800 in cell viability test so that it could be utilized for detecting trace Al3+ in vitro in a concentration-dependent manner via confocal imaging which proved its potential of diagnosis and treatment of Aluminum related diseases.

Comparative assessment of direct and indirect cold atmospheric plasma effects, based on helium and argon, on human glioblastoma: an in vitro and in vivo study

Recent research has highlighted the promising potential of cold atmospheric plasma (CAP) in cancer therapy. However, variations in study outcomes are attributed to differences in CAP devices and plasma parameters, which lead to diverse compositions of plasma products, including electrons, charged particles, reactive species, UV light, and heat. This study aimed to evaluate and compare the optimal exposure time, duration, and direction-dependent cellular effects of two CAPs, based on argon and helium gases, on glioblastoma U-87 MG cancer cells and an animal model of GBM. Two plasma jets were used as low-temperature plasma sources in which helium or argon gas was ionized by high voltage (4.5 kV) and frequency (20 kHz). In vitro assessments on human GBM and normal astrocyte cell lines, using MTT assays, flow cytometry analysis, wound healing assays, and immunocytochemistry for Caspase3 and P53 proteins, demonstrated that all studied plasma jets, especially indirect argon CAP, selectively induced apoptosis, hindered tumor cell growth, and inhibited migration. These effects occurred concurrently with increased intracellular levels of reactive oxygen species and decreased total antioxidant capacity in the cells. In vivo results further supported these findings, indicating that single indirect argon and direct helium CAP therapy, equal to high dose Temozolomide treatment, induced tumor cell death in a rat model of GBM. This was concurrent with a reduction in tumor size observed through PET-CT scan imaging and a significant increase in the survival rate. Additionally, there was a decrease in GFAP protein levels, a significant GBM tumor marker, and an increase in P53 protein expression based on immunohistochemical analyses. Furthermore, Ledge beam test analysis revealed general motor function improvement after indirect argon CAP therapy, similar to Temozolomide treatment. Taken together, these results suggest that CAP therapy, using indirect argon and direct helium jets, holds great promise for clinical applications in GBM treatment.

Glioma Single-Cell Biomechanical Analysis by Cyclic Conical Constricted Microfluidics.

Determining the grade of glioma is a critical step in choosing patients' treatment plans in clinical practices. The pathological diagnosis of patient's glioma samples requires extensive staining and imaging procedures, which are expensive and time-consuming. Current advanced uniform-width-constriction-channel-based microfluidics have proven to be effective in distinguishing cancer cells from normal tissues, such as breast cancer, ovarian cancer, prostate cancer, etc. However, the uniform-width-constriction channels can result in low yields on glioma cells with irregular morphologies and high heterogeneity. In this research, we presented an innovative cyclic conical constricted (CCC) microfluidic device to better differentiate glioma cells from normal glial cells. Compared with the widely used uniform-width-constriction microchannels, the new CCC configuration forces single cells to deform gradually and obtains the biophysical attributes from each deformation. The human-derived glioma cell lines U-87 and U-251, as well as the human-derived normal glial astrocyte cell line HA-1800 were selected as the proof of concept. The results showed that CCC channels can effectively obtain the biomechanical characteristics of different 12-25 μm glial cell lines. The patient glioma samples with WHO grades II, III, and IV were tested by CCC channels and compared between Elastic Net (ENet) and Lasso analysis. The results demonstrated that CCC channels and the ENet can successfully select critical biomechanical parameters to differentiate the grades of single-glioma cells. This CCC device can be potentially further applied to the extensive family of brain tumors at the single-cell level.

Chalcone 9X Contributed to Repressing Glioma Cell Growth and Migration and Inducing Cell Apoptosis by Reducing FOXM1 Expression In Vitro and Repressing Tumor Growth In Vivo.

Objective Natural and synthetic chalcones played roles in inflammation and cancers. Chalcone 9X was an aromatic ketone that was found to inhibit cell growth of hepatic cancer and lung cancer cells. In this study, we wanted to investigate the functions of Chalcone 9X in glioma. Materials and Methods Chemical Chalcone 9X was added in human glioma cell lines (U87 and T98G cells) and normal astrocyte cell lines (HA1800) with various concentrations (0 μmol/L, 20 μmol/L, 50 μmol/L, and 100 μmol/L). CCK-8 assay was used to measure cell viability. Flow cytometric assay was used to measure cell apoptotic rates. Wound healing assay and transwell assay were used to measure cell invasion. RT-PCR was used to detect relative mRNA expressions, and the protein expressions were detected by western blot (WB) and immunohistochemical staining (IHC). Finally, nude mouse xenograft assay was performed to prove the effects of Chalcone 9X in vivo. Results Results revealed that Chalcone 9X treatment suppressed cell viability and cell migration capacity; it could also induce cell apoptosis in U87 and T98G cells with dose dependence. However, it had little cytotoxicity to normal astrocyte HA1800 cells. Moreover, Chalcone 9X treatment could repress the mRNA and protein expressions of FOXM1 in human glioma cell lines, which was an oncogene that could promote the progression and malignancy of glioma. In addition, FOXM1 overexpression dismissed the Chalcone 9X effects on cell proliferation, apoptosis, and migration in human glioma cell lines. Finally, in vivo assay showed that Chalcone 9X treatment repressed the expression of FOXM1, which inhibited the tumor growth of a xenograft model injected with U87 in nude mice. Conclusions In all, we found that Chalcone 9X could suppress cell proliferation and migration and induce cell apoptosis in human glioma cells, while it has little cytotoxicity to normal astrocyte cells. Therefore, we uncovered a novel way that Chalcone 9X could inhibit FOXM1 expression and repress the progression and biofunctions of glioma cells, which might be a potential therapeutic drug for treating human glioma.

Iron oxide nanoparticles-loaded hyaluronic acid nanogels for MRI-aided Alzheimer's disease theranostics

Despite eye-opening advances in developing novel therapeutics for hard-to-treat diseases, treatment of Alzheimer's disease (AD) is still known as the challenge of generations. By the way, scrutinizing and shedding light on a major cause of AD, i.e., fibrillation of β amyloid (Aβ) peptides, have paved the way to find an effective therapy for this life-threatening disease in the foreseeable future. In this study, we endeavored to push forward with research on AD therapy, even as much as an inch, by fabricating and evaluating a theranostic system based on iron oxide nanoparticles-loaded hyaluronic acid nanogels (Fe 3 O 4 -HyA NGs). Fe 3 O 4 nanoparticles were fabricated via a facile co-precipitation method and were loaded in HyA NGs in situ by formation of NGs using a thiolated HyA (HyA-SH) precursor. Standard structural analysis was performed on Fe 3 O 4 -HyA NGs, and the results revealed the NGs were negatively charged, which led to relatively poor adsorption of plasma proteins, and sized at the range of 120–150 nm. Also, Fe 3 O 4 -HyA NGs showed a superparamagnetic property with a magnetic saturation of about 62.8 emu/g indicating the successful loading of Fe 3 O 4 nanoparticles. Besides, findings of the cytotoxicity analysis could primarily show the NGs did not pose a noticeable risk to normal astrocyte cells (i.e., 96.7% cell viability at 100 µg/ml after 48 h treatment). Moreover, in vitro magnetic resonance imaging (MRI) analysis could reveal the noticeable potential ability of the Fe 3 O 4 -HyA NGs to generate negative contrast by reducing both T2-weighted and T2*-weighted MR signal intensities with a relaxation rate (r 2 ) of about 120.87 (1/mM.sec). Finally, Fe 3 O 4 -HyA NGs exhibited a potential ability to impede Aβ aggregation by around 44% at 10 µM; also, they could induce disaggregation of Aβ fibrils by about 13% at 10 µM. Hence, Fe 3 O 4 -HyA NGs could be a promising choice for AD theranostics and could be further scrutinized in vitro and in vivo .

Cold Plasma Discharge Tube Enhances Antitumoral Efficacy of Temozolomide.

Glioblastoma (GBM) is a fatal human brain tumor with a low survival rate. Temozolomide (TMZ) has been widely used in GBM therapy with noticeable side effects. Cold plasma is an ionized gas that is generated near room temperature. Here, we demonstrated the enhancement therapeutic efficacy of TMZ via using a cold plasma source based on nonequilibrium plasma in a sealed glass tube, named a radial cold plasma discharge tube (PDT). The PDT affected glioblastoma cells' function just by its electromagnetic (EM) emission rather than any chemical factors in the plasma. The PDT selectively increased the cytotoxicity of TMZ on two typical glioblastoma cell lines, U87MG and A172, compared with normal astrocyte cell line hTERT/E6/E7 to some extent. Furthermore, on the basis of a patient-derived xenograft model, our preliminary in vivo studies demonstrated the drastically improved mean survival days of the tumor-barrier mice by more than 100% compared to control. The PDT is not only independent of continuous helium supply but is also capable of resisting the interference of environmental changes. Thus, the PDT was a stable and low-cost cold atmospheric plasma source. In short, this study is the first to demonstrate the promising application of PDTs in GBM therapy as a noninvasive and portable modality.

Matteucinol combined with temozolomide inhibits glioblastoma proliferation, invasion, and progression: an in vitro, in silico, and in vivo study.

Glioblastoma is the most prevalent and malignant brain tumor identified in adults. Surgical resection followed by radiotherapy and chemotherapy, mainly with temozolomide (TMZ), is the chosen treatment for this type of tumor. However, the average survival of patients is around 15 months. Novel approaches to glioblastoma treatment are greatly needed. Here, we aimed to investigate the anti-glioblastoma effect of the combination of matteucinol (Mat) (dihydroxyflavanone derived from Miconia chamissois Naudin) with the chemotherapeutic TMZ in vitro using tumor (U-251MG) and normal astrocyte (NHA) cell lines and in vivo using the chick embryo chorioallantoic membrane (CAM) assay. The combination was cytotoxic and selective for tumor cells (28 μg/mL Mat and 9.71 μg/mL TMZ). Additionally, the combination did not alter cell adhesion but caused morphological changes characteristic of apoptosis in vitro. Notably, the combination was also able to reduce tumor growth in the chick embryo model (CAM assay). The docking results showed that Mat was the best ligand to the cell death membrane receptor TNFR1 and to TNFR1/TMZ complex, suggesting that these two molecules may be working together increasing their potential. In conclusion, Mat-TMZ can be a good candidate for pharmacokinetic studies in view of clinical use for the treatment of glioblastoma.

Upregulation of hsa-miR-196a-5p is associated with MIR196A2 methylation and affects the malignant biological behaviors of glioma

Hsa-miR-196a-5p is involved in tumorigenesis and progression. However, the driving factors for hsa-miR-196a-5p overexpression and its correlation with the clinicopathological features and prognosis of patients remain unclear in glioma. Thus, this study aimed to investigate the prognostic value of hsa-miR-196a-5p and its correlation with MIR196A2 methylation in glioma. We observed that hsa-miR-196a-5p expression was upregulated in glioma. Next, 112 patients were divided into high (n = 56) and low (n = 56) hsa-miR-196a-5p expression groups. The chi-square test showed that hsa-miR-196a-5p expression was significantly related to age, WHO grade, histopathology, IDH mutation status, and 1p/19q codeletion. Univariate and multivariate Cox regression analyses showed that hsa-miR-196a-5p expression was an independent prognostic factor. GO and KEGG enrichment analyses showed that hsa-miR-196a-5p may be involved in the MAPK signaling, focal adhesion and cancer-related pathways. Compared with the normal astrocyte cell line, glioma cell lines had an unregulated MIR196A2 methylation level, which was confirmed by TCGA data. The hypermethylated CpG sites of MIR196A2 were mainly concentrated in the gene body region, which was significantly associated with hsa-miR-196a-5p overexpression. Kaplan-Meier curves revealed that MIR196A2 hypermethylation was a poor prognostic factor. These findings suggest that hsa-miR-196a-5p overexpression may be involved in malignant biological behaviors, and MIR196A2 hypermethylation of the gene body was significantly associated with hsa-miR-196a-5p overexpression, which was a poor prognostic factor of glioma. Therefore, MIR196A2 hypermethylation may act as an early marker of prognosis of patients with glioma.

Tumor cell and immune cell profiles in primary human glioblastoma: Impact on patient outcome.

The distribution and role of tumor‐infiltrating leucocytes in glioblastoma (GBM) remain largely unknown. Here, we investigated the cellular composition of 55 primary (adult) GBM samples by flow cytometry and correlated the tumor immune profile with patient features at diagnosis and outcome. GBM single‐cell suspensions were stained at diagnosis (n = 44) and recurrence following radiotherapy and chemotherapy (n = 11) with a panel of 8‐color monoclonal antibody combinations for the identification and enumeration of (GFAP+CD45−) tumor and normal astrocytic cells, infiltrating myeloid cells —i.e. microglial and blood‐derived tumor‐associated macrophages (TAM), M1‐like, and M2‐like TAM, neutrophils. and myeloid‐derived suppressor cells (MDSC)— and tumor‐infiltrating lymphocytes (TIL) —i.e. CD3+T‐cells and their TCD4+, TCD8+, TCD4−CD8−, and (CD25+CD127lo) regulatory (T‐regs) subsets, (CD19+CD20+) B‐cells, and (CD16+) NK‐cells—. Overall, GBM samples consisted of a major population (mean ± 1SD) of tumor and normal astrocytic cells (73% ± 16%) together with a significant but variable fraction of immune cells (24% ± 18%). Within myeloid cells, TAM predominated (13% ± 12%) including both microglial cells (10% ± 11%) and blood‐derived macrophages (3% ± 5%), in addition to a smaller proportion of neutrophils (5% ± 9%) and MDSC (4% ± 8%). Lymphocytes were less represented and mostly included TCD4+ (0.5% ± 0.7%) and TCD8+ cells (0.6% ± 0.7%), together with lower numbers of TCD4−CD8− T‐cells (0.2% ± 0.4%), T‐regs (0.1% ± 0.2%), B‐lymphocytes (0.1% ± 0.2%) and NK‐cells (0.05% ± 0.05%). Overall, three distinct immune profiles were identified: cases with a minor fraction of leucocytes, tumors with a predominance of TAM and neutrophils, and cases with mixed infiltration by TAM, neutrophils, and T‐lymphocytes. Untreated GBM patients with mixed myeloid and lymphoid immune infiltrates showed a significantly shorter patient overall survival versus the other two groups, in the absence of gains of the EGFR gene (p = 0.02). Here we show that immune cell infiltrates are systematically present in GBM, with highly variable levels and immune profiles. Patients with mixed myeloid and T‐lymphoid infiltrates showed a worse outcome.

Hypoxia preconditioning improves structure and function of astrocytes mitochondria via PGC-1α/HIF signal

The protective effect of astrocytes on nerves was demonstrated by mitochondrial transfer. The neuroprotective effect of hypoxic pretreatment is widely accepted. The aim of this research is to investigate the role of hypoxic preconditioning on astrocytes mitochondria. Rat neuronal cells and astrocytes were isolated and cultured. A hypoxic preconditioned astrocyte and oxygen glucose deprivation (OGD) neuronal cell co-culture experiment was used to detect the effect of hypoxic preconditioning (HP) on nerve damage. The silencing of proliferatoractivated receptor γ coactivator-1α (PGC-1α) with siRNA was used to explore the role of HP in the repair of nerve damage and biogenesis of mitochondria. HP increased astrocyte viability and promoted neuroprotective factor secretion. The expression levels of antioxidant enzymes, PGC-1α and uncoupling protein2 (UCP2) were up-regulated by HP. In addition, HP improved mitochondrial function and reduced oxidative stress induced by OGD. It was found that HP astrocytes had a greater neuroprotective effect than normal astrocytes cells. Neuronal apoptosis and reactive oxygen species levels were down-regulated by cell co-culture. The PGC-1α siRNA experiment showed that hypoxia treatment promotes mitochondrial biogenesis and plays a neuroprotective role. HP significantly enhanced the efficacy of astrocytes in the treatment of neuronal injury.

Effect of Piezo1 Overexpression on Peritumoral Brain Edema in Glioblastomas

Previous studies have suggested that increased mortality and disability in patients with brain tumor are associated with peritumoral brain edema. However, the mechanism of peritumoral brain edema in brain tumors is unknown. This study aimed to investigate the effect of Piezo1 overexpression on peritumoral brain edema in glioblastomas. The Piezo1 expression in cell lines and paired samples was detected by quantitative reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry. Sixty-four patients with glioblastomas were analyzed retrospectively. The Piezo1 expression of tumor tissue was detected by immunohistochemistry. The diameters of tumor and edema were measured by preoperative MR imaging, and the edema index value was calculated. Western blot and quantitative reverse transcription polymerase chain reaction showed that Piezo1 expression was higher in 6 glioma cell lines than in the normal astrocyte cell line. Compared with peritumoral tissues, Piezo1 was up-regulated in tumor tissues. Sixty-four patients with glioblastomas were enrolled in further study. Piezo1 was higher in the moderate edema group than in the mild edema group (P < .001), higher in the severe edema group than in the moderate edema group (P < .001), and correlated with the edema index (r = 0.73; P < .001). Receiver operating characteristic curve analysis showed that the edema index yielded an area under the curve of 0.867 (95% CI, 0.76-0.97; P < .001), with a sensitivity of 100% and a specificity of 70%. Piezo1 overexpression is positively correlated with the degree of peritumoral brain edema in glioblastomas. Predicting high Piezo1 expression in tumor tissues based on the edema extent shows good sensitivity and specificity.

Circular RNA SFMBT2 Inhibits the Proliferation and Metastasis of Glioma Cells Through Mir-182-5p/Mtss1 Pathway.

Glioma is a common type of tumor in human central nervous system, and it is characterized with high mobility and mortality. The prognosis of patients with advanced glioma remains poor. Thus, it is necessary to develop novel therapeutic approaches for the treatment of this disease. Circular RNAs are a group of noncoding RNAs which have been detected in eukaryotic cells. They are tissue-specific and characterized with a more stable structure compared with linear RNAs. Recently, studies have revealed that certain circular RNAs are involved in biological processes such as gene regulation; however, the functions of most circular RNAs remain unknown and require further investigation. Furthermore, circular RNAs can act as “sponges” of its target microRNA, consequently suppressing their activity. Additionally, impaired expression of circular RNAs is reported in different diseases including cancer. In our study, low expression of circular RNA Scm like with 4 Mbt domains 2 was detected in glioma samples. Furthermore, reduced circRNA Scm like with 4 Mbt domains 2 expression was observed in human glioma cell lines compared to normal astrocyte cells. Additionally, overexpression of circRNA Scm like with 4 Mbt domains 2 suppressed the growth and metastasis of glioma cells in vitro. Moreover, microRNA-182-5p could be a downstream molecule of circRNA Scm like with 4 Mbt domains 2. The influenced of microRNA-182-5p-induced proliferation, migration, and invasion of glioma cells could be abrogated by overexpressed circRNA Scm like with 4 Mbt domains 2. In addition, metastasis suppressor 1 was predicted as a novel target of microRNA-182-5p, and its expression was restored by circRNA Scm like with 4 Mbt domains 2. In summary, our findings provided novel insight into the roles of circRNA Scm like with 4 Mbt domains 2 in glioma. More importantly, circRNA Scm like with 4 Mbt domains 2/microRNA-182-5p/metastasis suppressor 1 axis could be a putative therapeutic target for the treatment of patients with glioma.

The expression of microRNA-532-5p in glioma and mechanism research

Objective To explore the expression of microRNA(miRNA, miR)-532-5p in primary glioma and to detect the effects of miR-532-5p overexpression on proliferation, migration and invasion in U251 glioma cell line. Methods Real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) was conducted to measure the expression of miR-532-5p in 30 cases of glioma tissues and traumatic brain specimens. We then analyzed the relationship of the level of miR-532-5p and the clinical pathological data of glioma patients. After transfection with miR-532-5p, the effects of on proliferation, migration and invasion were detected using methyl thiazol tetrazolium (MTT) assay, wound healing assay and transwell assay. Results The relative expression of miR-532-5p was significantly lower in glioma tissues(0.381±0.310) than in normal brain tissues (1.040±0.470, P<0.01). The level of miR-532-5p was significantly associated with Karnofsky (KPS) scores and seizures. Expression of miR-532-5p in U251 cell line (0.280±0.080) were significantly higher than those in Normal Human Astrocyte (NHA) cell line (1.021±0.069, P<0.01). The proliferation [(59.5±9.5)%, P<0.01], migration [(55.4±4.2)%, P<0.05] an invasion [(45.7±6.3)%, P<0.01] of U251 cell with miR-532-5p mimic transfection were significantly lower than those in miR-532-5p negative control after transfection. Conclusion The expression of miR-532-5p were decreased in patients with glioma. The low level of miR-532-5p was significantly associated with the KPS scores and seizures. It was shown that miR-532-5p was associated with proliferation, migration and invasion in U251 cell line and high expression of miR-532-5p was significantly associated with the KPS scores and seizures Overexpression of miR-532-5p could inhibit the capability of proliferation, migration and invasion. Key words: MicroRNA-532-5p; Glioma; Migration; Invasion; Pathological parameters

Dp71 Expression in Human Glioblastoma.

Background: Dp71 is the most abundant dystrophin (DMD) gene product in the nervous system. Mutation in the Dp71 coding region is associated with cognitive disturbances in Duchenne muscular dystrophy (DMD) patients, but the function of dystrophin Dp71 in tumor progression remains to be established. This study investigated Dp71 expression in glioblastoma, the most common and aggressive primary tumor of the central nervous system (CNS). Methods: Dp71 expression was analyzed by immunofluorescence, immunohistochemistry, RT-PCR, and immunoblotting in glioblastoma cell lines and cells isolated from human glioblastoma multiforme (GBM) bioptic specimens. Results: Dp71 isoform was expressed in normal human astrocytes (NHA) cell lines and decreased in glioblastoma cell lines and cells isolated from human glioblastoma multiforme bioptic specimens. Moreover, Dp71 was localized in the nucleus in normal cells, while it was localized into the cytoplasm of glioblastoma cells organized in clusters. We have shown, by double labeling, that Dp71 colocalizes with lamin B in normal astrocytes cells, confirming the roles of Dp71 and lamin B in maintaining nuclear architecture. Finally, we demonstrated that decreased Dp71 protein in cells isolated from human bioptic specimens was inversely correlated with the Ki-67 tumor proliferative index. Conclusion: A decreased Dp71 expression is associated with cancer proliferation and poor prognosis in glioblastoma.

Long non‑coding RNA MEG3 suppresses the growth of glioma cells by regulating the miR‑96‑5p/MTSS1 signaling pathway

Glioma is one of the most common types of tumor of the central nervous system with high mobility and mortality. The prognosis of patients with high-grade glioma is poor. Therefore, it is urgent to develop the therapeutic strategies for the treatment of glioma. Long non-coding RNAs (lncRNAs) have been reported as potential inducers or suppressors of numerous types of tumors including glioma. Previous studies have revealed that lncRNA maternally expressed gene 3 (MEG3) is involved in the initiation and progression of cancer; however, the underlying mechanisms remain unclear. In the present study, MEG3 was downregulated in glioma tissue. In addition, downregulation of MEG3 was observed in human glioma cell lines compared with normal astrocyte cells. Furthermore, overexpressed MEG3 inhibited the proliferation, migration and invasion of glioma cells. Additionally, microRNA-96-5p (miR-96-5p) was a promising target of MEG3, and the promoting effects of miR-96-5p on cell growth and metastasis could be reversed by upregulated MEG3. Metastasis suppressor 1 (MTSS1) was predicted as the putative target of miR-96-5p, and its expression was restored by MEG3. In summary, the present data provided novel insight into the roles of MEG3 in glioma, and MEG3/miR-96-5p/MTSS1 signaling could be a promising therapeutic target for the treatment of patients with glioma.

PTB-AS, a Novel Natural Antisense Transcript, Promotes Glioma Progression by Improving PTBP1 mRNA Stability with SND1.

Glioma, the most common primary malignancy in the brain, has high recurrence and lethality rates, and thus, elucidation of the molecular mechanisms of this incurable disease is urgently needed. Poly-pyrimidine tract binding protein (PTBP1, also known as hnRNP I), an RNA-binding protein, has various mechanisms to promote gliomagenesis. However, the mechanisms regulating PTBP1 expression are unclear. Herein, we report a novel natural antisense noncoding RNA, PTB-AS, whose expression correlated positively with PTBP1 mRNA. We found that PTB-AS significantly promoted the proliferation and migration invivo and invitro of glioma cells. PTB-AS substantially increased the PTBP1 level by directly binding to its 3' UTR and stabilizing the mRNA. Furthermore, staphylococcal nuclease domain-containing 1 (SND1) dramatically increased the binding capacity between PTB-AS and PTBP1 mRNA. Mechanistically, PTB-AS could mask the binding site of miR-9 in the PTBP1-3' UTR; miR-9 negatively regulates PTBP1. To summarize, we revealed that PTB-AS, which maintains the PTBP1 level through extended base pairing to the PTBP1 3' UTR with the assistance of SND1, could significantly promote gliomagenesis.

A phthalimidoalkanamide derived novel DNMT inhibitor enhanced radiosensitivity of A549 cells by inhibition of homologous recombination of DNA damage.

Purpose To elucidate the radiosensitizing effect and underlying mechanism of a new kind of DNA methyltransferase (DNMT) inhibitor with biological availability. Methods A novel non-nucleoside compound, designated as MA-17, was recently derived from a phthalimido alkanamide structure. DNMT expressions were confirmed in cultured human lung cancer (A549) and normal astrocyte (NHA) cells, radiosensitivity was measured using clonogenic assay, and assays of cell cycle alteration, apoptosis, DNA damage repair, and differential gene expression were undertaken. Results MA-17 significantly radiosensitized A549 cells with a mean dose enhancement ratio (DER) of 1.43 at the surviving fraction of 0.2 (p < 0.05 by one-tailed ratio paired t-test). MA-17 did not affect normal astrocytes (mean DER0.2, 1.016; p = 0.420). MA-17 demonstrated a mean half-life of 1.0h in vivo and a relatively even distribution in various tissues. Pretreatment with MA-17 increased sub-G1 fractions and inhibited the repair of DNA double-strand breaks, which are induced by irradiation. We found that MA-17 also down-regulated DNA homologous recombination and the Fanconi anemia pathway (FANCA, BRCA1, and RAD51C) in A549 cells. This bioinformatics finding was confirmed in validation Western blot to evaluate the expression of vital proteins. Conclusions A novel phthalimido alkanamide derivative, a DNMT inhibitor, possessed both biostability and favorable and substantial radiosensitizing effects by augmenting apoptosis or inhibiting DNA damage repair.

Radiosensitization of Glioblastoma Cells by a Novel DNA Methyltransferase-inhibiting Phthalimido-Alkanamide Derivative.

Strategies to enhance the therapeutic ratio of radiotherapy in glioblastoma are warranted. Our aim was to report a novel DNA methyltransferase inhibitor as a potential radiosensitizing agent in glioblastoma. Four glioblastoma cell lines and one normal astrocyte cell line were incubated with a newly-synthetized phthalimido-alkanamide derivative, MA17, and its radiosensitizing effects were assessed. We performed a tumor growth delay assay in two glioblastoma lines: U87MG and U138MG. We evaluated DNA methyltransferase (DNMT) inhibition, apoptosis, autophagy, DNA damage repair, and FANCA expression. MA17 radiosensitized all glioblastoma cells (all p<0.05), but it did not affect normal astrocytes (p=0.193). MA17 significantly prolonged the mean tumor doubling time in vivo, in cells treated in addition with radiotherapy, compared to radiotherapy alone (p<0.05). DNMT activity was down-regulated, and apoptosis and autophagy were induced by MA17. Double-stranded DNA break foci were observed for prolonged periods in cells treated with MA17. FANCA expression was also inhibited. A novel phthalimido-alkanamide derivative demonstrated significant radiosensitization in glioblastoma cells in vitro and in vivo. Further investigation is needed to translate these results to the clinic.

CFTR activation suppresses glioblastoma cell proliferation, migration and invasion

The aim of this study was to investigate the function of Cystic fibrosis transmembrane conductance regulator (CFTR) in human glioblastoma (GBM) cells. Data dining results of the Human Protein Atlas showed that low CFTR expression was associated with poor prognosis for GBM patients. We found that CFTR protein expression was lower in U87 and U251 GBM cells than that in normal humane astrocyte cells. CFTR activation significantly reduced GBM cell proliferation. In addition, CFTR activation significantly abrogated migration and invasion of GBM cells. Besides, CFTR activator Forskolin treatment markedly reduced MMP-2 protein expression. These effects of CFTR activation were significantly inhibited by CFTR inhibitor CFTRinh-172 pretreatment. Our findings suggested that JAK2/STAT3 signaling was involved in the anti-glioblastoma effects of CFTR activation. Moreover, CFTR overexpression in combination with Forskolin induced a synergistic anti-proliferative response in U87 cells. Overall, our findings demonstrated that CFTR activation suppressed GBM cell proliferation, migration and invasion likely through the inhibition of JAK2/STAT3 signaling.