Exploring the causal role of immune cells in cerebral aneurysm through single-cell transcriptomics and Mendelian randomization analysis.

Cerebral aneurysm (CA) represents a significant clinical challenge, characterized by pathological dilation of cerebral arteries. Recent evidence underscores the crucial involvement of immune cells in CA pathogenesis. This study aims to explore the complex interplay between immune cells and CA formation. We analyzed single-cell RNA sequencing data from the GSE193533 dataset, focusing on unruptured CA and their controls. Comprehensive cell-type identification and pseudo-time trajectory analyses were conducted to delineate the dynamic shifts in immune cell populations. Additionally, a two-sample Mendelian randomization (MR) approach was employed to investigate the causal influence of various immunophenotypes on CA susceptibility and the reciprocal effect of CA formation on immune phenotypes. Single-cell transcriptomic analysis revealed a progressive loss of vascular smooth muscle cells (VSMCs) and an increase in monocytes/macrophages (Mo/MΦ) and other immune cells, signifying a shift from a structural to an inflammatory milieu in CA evolution. MR analysis identified some vital immunophenotypes, such as CD64 on CD14+ CD16+ monocytes (OR: 1.236, 95% CI: 1.064-1.435, P = 0.006), as potential risk factors for CA development, while others, like CD28- CD8br %CD8br (OR: 0.883, 95% CI: 0.789-0.988, P = 0.030), appeared protective. Reverse MR analysis demonstrated that CA formation could modulate specific immunophenotypic expressions, highlighting a complex bidirectional interaction between CA pathology and immune response. This study underscores the pivotal role of immune cells in this process through the integration of single-cell transcriptomics with MR analysis, offering a comprehensive perspective on CA pathogenesis, and potentially guiding future therapeutic strategies targeting specific immune pathways.

Overexpression of PPM1B inhibited chemoresistance to temozolomide and proliferation in glioma cells.

Protein phosphatase magnesium-dependent 1B (PPM1B) functions as IKKß phosphatases to terminate nuclear factor kappa B (NF-κB) signaling. NF-κB signaling was constitutively activated in glioma cells. At present, little is known about the role of PPM1B in glioma. In the current study, we found that the expression of PPM1B was reduced in glioma tissues and cells, and decreased expression of PPM1B was related to poor overall survival of patients. Overexpression of PPM1B inhibited the proliferation and promoted apoptosis of glioma cells. Moreover, PPM1B overexpression reduced the phosphorylation of IKKß and inhibited the nuclear localization of NF-κBp65. PDTC, an inhibitor of NF-κB signaling, reversed PPM1B-knockdown-induced cell proliferation. Furthermore, overexpression of PPM1B enhanced the sensitivity of glioma cells to temozolomide. In vivo experiments showed that overexpression of PPM1B could inhibit tumor growth, improve the survival rate of nude mice, and enhance the sensitivity to temozolomide. In conclusion, PPM1B suppressed glioma cell proliferation and the IKKß-NF-κB signaling pathway, and enhanced temozolomide sensitivity of glioma cells.

LncRNA SNHG15 regulates autophagy and prevents cerebral ischaemia-reperfusion injury through mediating miR-153-3p/ATG5 axis.

Ischaemic stroke is a common cerebrovascular disease. Long non-coding RNA (lncRNA) of small nucleolar RNA host gene (SNHG15) has been supposedly performed a regulatory role in many diseases. Nonetheless, the function of SNHG15 in cerebral ischaemia-reperfusion injury has not been clarified. The OGD/R of Neuro2A cells simulated the ischaemic and reperfused states of the brain. Neuro2a cell line with stable transfection of plasmid with silent expression of SNHG15 was constructed. Neuro2a cell lines transfected with miR-153-3p mimic (miR-153-3p-mimics) and miR-153-3p inhibitor (miR-153-3p-inhibition) were constructed. Expression of SNHG15, mi R-200a, FOXO3 and ATG7 in mouse brain tissue and N2a cells was identified by qRT-PCR. Western blot (WB) analysis of mouse brain tissue and Neuro2a cells revealed the presence of the proteins ATG5, Cle-caspase-3, Bax, Bcl-2, LC3 II/I and P62 (WB). The representation and distribution of LC3B were observed by immunofluorescence. The death of cells was measured using a technique called flow cytometry (FACS). SNHG15 was highly expressed in cerebral ischaemia-reperfusion injury model. Down-regulation of SNHG15 lead to lower apoptosis rate and decreased autophagy. Dual luciferase assay and co-immunoprecipitation (CoIP) found lncRNA SNHG15/miR-153-3p/ATG5. Compared to cells transfected with NC suppression, cells transfected with miR-153-3p-inhibition had substantially greater overexpression of LC 3 II/I, ATG5, cle-Caspase-3, and Bax, as determined by a recovery experiment, the apoptosis rate was elevated, yet both P62 and Bcl-2 were significantly lower and LC3+ puncta per cells were significantly increased. Co-transfection of miR-153-3p-inhibition and sh-SNHG15 could reverse these results. LncRNA SNHG15 regulated autophagy and prevented cerebral ischaemia-reperfusion injury through mediating the miR-153-3p/ATG5 axis.

Knock-down of PGM1 inhibits cell viability, glycolysis, and oxidative phosphorylation in glioma under low glucose condition via the Myc signaling pathway.

PGM1 is an essential enzyme for glucose metabolism and is involved in cell viability, proliferation, and metabolism. However, the regulatory role of PGMI in glioma progression and the relation between gliomas and PGM1 expression are still unclear. This study aimed to explore the role of PGM1 in glycolysis and oxidative phosphorylation in glioma. Correlation and enrichment analyses of PGM1 in glioma cells were explored in TCGA database and two hospital cohorts. The cell viability, glycolysis, and oxidative phosphorylation were investigated in PGM1 knock-down and overexpression situations. Higher PGM1 expression in glioma patients was associated with a poor survival rate. However, knock-down of PGM1 reduced glioma cell viability, glycolysis, and oxidative phosphorylation under low glucose condition. Moreover, it suppressed tumor growth in vivo. On the other hand, PGM1 overexpression promoted glioma cell viability, glycolysis, and oxidative phosphorylation under low glucose condition by a Myc positive feedback loop. Glioma patients with higher PGM1 expression were associated with poor survival rates. Additionally, PGM1 could promote glioma cell viability, glycolysis, and oxidative phosphorylation under low glucose condition via a myc-positive feedback loop, suggesting PGM1 could be a potential therapeutic target for gliomas.

Establishment and Validation of a Prognostic Immune Signature in Neuroblastoma.

BACKGROUND: Neuroblastoma (NBL) is the most common extracranial solid tumor in childhood, and patients with high-risk neuroblastoma had a relatively poor prognosis despite multimodal treatment. To improve immunotherapy efficacy in neuroblastoma, systematic profiling of the immune landscape in neuroblastoma is an urgent need. METHODS: RNA-seq and according clinical information of neuroblastoma were downloaded from the TARGET database and GEO database (GSE62564). With an immune-related-gene set obtained from the ImmPort database, Immune-related Prognostic Gene Pairs for Neuroblastoma (IPGPN) for overall survival (OS) were established with the TARGET-NBL cohort and then verified with the GEO-NBL cohort. Immune cell infiltration analysis was subsequently performed. The integrated model was established with IPGPN and clinicopathological parameters. Immune cell infiltration was analyzed with the XCELL algorithm. Functional enrichment analysis was performed with clusterProfiler package in R. RESULTS: Immune-related Prognostic Gene Pairs for Neuroblastoma was successfully established with seven immune-related gene pairs (IGPs) involving 13 unique genes in the training cohort. In the training cohort, IPGPN successfully stratified neuroblastoma patients into a high and low immune-risk groups with different OS (HR=3.92, P = 2 × 10-8) and event-free survival (HR=3.66, P=2 × 10-8). ROC curve analysis confirmed its predictive power. Consistently, high IPGPN also predicted worse OS (HR=1.84, P = .002) and EFS in validation cohort (HR=1.38, P = .06) Moreover, higher activated dendritic cells, M1 macrophage, Th1 CD4+, and Th2 CD4+ T cell enrichment were evident in low immune-risk group. Further integrating IPGPN with age and stage demonstrated improved predictive performance than IPGPN alone. CONCLUSION: Herein, we presented an immune landscape with IPGPN for prognosis prediction in neuroblastoma, which complements the present understanding of the immune signature in neuroblastoma.

LncRNA Gm4419 contributes to OGD/R injury of cerebral microglial cells via IκB phosphorylation and NF-κB activation.

Ischemic stroke is one of major causes of adult morbidity. Recent studies have shown that over-activated microglial cells play a critical role in aggravating cerebral oxygen glucose deprivation/reoxygenation (OGD/R) damage by releasing excessive inflammatory cytokines. However, the involving mechanisms are not distinct yet. Long non-coding RNAs (lncRNAs) have been reported to in participate in lots of complicated biological processes. Our understandings of the relationship between lncRNAs and OGD/R injury are largely limited. In this study, we demonstrated that a lncRNA Gm4419 functioned as a crucial mediator in the activation of NF-κB signaling pathway, causing neuroinflammation damage during OGD/R. Gm4419 was abnormally up-regulated in OGD/R-treated microglial cells. We found that the high level of Gm4419 promoted the phosphorylation of IκBα by physically associating with IκBα, therefore, led to increased nucleus NF-κB levels for the transcriptional activation of TNF-α, IL-1ß and IL-6. In addition, we also demonstrated that knockdown of Gm4419 functioned as NF-κB inhibitor in OGD/R microglial cells, showing that down-regulation of Gm4419 had protective role against OGD/R injury. In summary, Gm4419 is required for microglial cell OGD/R injury though the activation of NF-κB signaling. Thus, Gm4419 appears to be a promising therapeutic target for ischemic stroke.

Long non-coding RNA Gm4419 promotes trauma-induced astrocyte apoptosis by targeting tumor necrosis factor α.

Traumatic brain injury (TBI) remains a life-threatening disease. Accumulating evidences have showed that neuroinflammatory response is a critical biological event in the progression of TBI induced astrocyte damage. However, the exact mechanisms are not well understood. In this study, we demonstrated that long non-coding RNA (lncRNA) Gm4419 promoted trauma-induced astrocyte apoptosis by up-regulating the expression of inflammatory cytokine tumor necrosis factor α (TNF-α). We observed that Gm4419 was aberrantly induced after injury on astroglial cells in vitro. Overexpression of Gm4419 in injury-treated astrocytes increased protein expressions of TNF-α, Bax, cleaved caspase-3 and cleaved caspase-9, decreased levels of Bcl-2 and CyclinD1, and significantly led to cellular apoptosis. Mechanically, Gm4419 transcript could function as a sponge for miR-466l and miR-466l could target TNF-α 3' UTR for degradation and translation inhibition. Therefore, Gm4419 could up-regulate TNF-α expression by competitively binding miR-466l and then contribute to inflammatory damage as well as astrocyte apoptosis during TBI. Generally speaking, our findings provide better understandings of the mechanism underlying Gm4419 in trauma-induced neuroinflammation and neurological deficits. Thus, the present study would expand the insight into the novel approaches for TBI therapy.

Nuclear SMAD2 restrains proliferation of glioblastoma.

AIMS: Although TGFß receptor signaling has been shown to play a role in regulation of the growth and metastasis of glioblastoma multiforme (GBM), the downstream pathway through either SMAD2 or SMAD3 has not been elucidated. In this study, we investigate whether nuclear SMAD2 can restrain the proliferation of glioblastoma. METHODS: A total of 23 resected specimens from GBM patients were collected for SMAD2 detection. Human GBM cell line A172, U87mg, D341m and Hs683 were maintained in Dulbecco's modified Eagle's medium and transfected with SMAD2 and SMAD3 shRNA plasmids. Gene expression was detected by RT-qPCR and Western and cell growth were detected by MTT assay. RESULTS: Our results showed that the phosphorylated SMAD2 (pSMAD2, the nuclear and functional form of SMAD2) levels in GBM were significantly lower than the paired normal brain tissue in patients. Depletion of SMAD2, but not SMAD3, significantly abolished the inhibitory effects of TGFß1 on the growth of GBM cells, possibly through pSMAD2-mediated increases in cell-cycle inhibitor, p27. CONCLUSION: Our data suggest that TGFß/SMAD2 signaling cascades restrains growth of GBM.

Effect of l-oxiracetam and oxiracetam on memory and cognitive impairment in mild-to-moderate traumatic brain injury patients: Study protocol for a randomized controlled trial.

Objectives: Patients with traumatic brain injury (TBI) often suffer memory and cognitive impairments, and oxiracetam-like drugs are considered to have a positive impact on these symptoms potentially. However, the efficacy and safety of l-oxiracetam and oxiracetam in TBI patients have not been sufficiently investigated. Methods: The study adopts a multicenter, randomized, double-blind, parallel-group, phase 3 clinical trial design in 74 centers across 51 hospitals in China. A total of 590 TBI patients meeting criteria will be randomly allocated into three groups in a 2:2:1 ratio: l-oxiracetam group, oxiracetam group, and placebo group. The treatment period is 14 days, with a follow-up period of 90 days. The primary outcome measure is the change in the Loewenstein Occupational Therapy Cognitive Assessment score at 90 days after treatment. Secondary outcomes include changes in other cognitive assessments, neurological function, activities of daily living, and safety assessments. Discussion: There is no robust evidence to suggest that l-oxiracetam and oxiracetam can enhance memory and cognitive function in patients with mild to moderate TBI. This study has the potential to answer this crucial clinical question. Trial registration: chinadrugtrials.org.cn, identifier CTR20192539; ClinicalTrials.gov, identifier NCT04205565.

Multimodality management for chronic subdural hematoma in China: protocol and characteristics of an ambidirectional, nationwide, multicenter registry study.

BACKGROUND: Despite its prevalence, there is ongoing debate regarding the optimal management strategy for chronic subdural hematoma (CSDH), reflecting the variability in clinical presentation and treatment outcomes. This ambidirectional, nationwide, multicenter registry study aims to assess the efficacy and safety of multimodality treatment approaches for CSDH in the Chinese population. METHODS/DESIGN: A multicenter cohort of CSDH patients from 59 participating hospitals in mainland China was enrolled in this study. The treatment modalities encompassed a range of options and baseline demographics, clinical characteristics, radiographic findings, and surgical techniques were documented. Clinical outcomes, including hematoma resolution, recurrence rates, neurological status, and complications, were assessed at regular intervals during treatment, 3 months, 6 months, 1 year, and 2 years follow-up. RESULT: Between March 2022 and August 2023, a comprehensive cohort comprising 2173 individuals who met the criterion was assembled across 59 participating clinical sites. Of those patients, 81.1% were male, exhibiting an average age of 70.12 ± 14.53 years. A historical record of trauma was documented in 48.0% of cases, while headache constituted the predominant clinical presentation in 58.1% of patients. The foremost surgical modality employed was the burr hole (61.3%), with conservative management accounting for 25.6% of cases. Notably, a favorable clinical prognosis was observed in 88.9% of CSDH patients at 3 months, and the recurrence rate was found to be 2.4%. CONCLUSION: This registry study provides critical insights into the multimodality treatment of CSDH in China, offering a foundation for advancing clinical practices, optimizing patient management, and ultimately, improving the quality of life for individuals suffering from this challenging neurosurgical condition. TRIAL REGISTRATION: ChiCTR2200057179.

Retraction notice to "Globularifolin exerts anticancer effects on glioma U87 cells through inhibition of Akt/mTOR and MEK/ERK signaling pathways in vitro and inhibits tumor growth in vivo" [Biochmie 142C (2017) 144-151].

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. Reason for retraction: Figures 5 and 7B show shared images with Figures 4 and 7 of a publication in Mol Med Reports, Zeng et al. (2018) 10.3892/mmr.2018.8599. The two manuscripts were submitted from different laboratories at almost exactly the same time. The authors were contacted but did not respond to the allegation.

DNA5mC Regulator-Mediated Molecular Clusters and Tumor Microenvironment Signatures in Glioblastoma.

Growing evidence links DNA methylation to tumor immunity. The impact of DNA methylation (5 mC) on the microenvironment surrounding tumors and immunotherapy remains to be clarified. Through clustering gene expression of 20 DNA methylation regulators, this study aimed at systematically analyzing DNA methylation regulator patterns and tumor microenvironment characteristics of TCGA-GBM patients. Various subtypes of glioblastoma exhibit different tumor microenvironments and DNA methylation patterns. Each DNA methylation modification was then assigned a DNA methylation score (DMS). High DMS was associated with a good prognosis. In contrast, the low DMS group had a relatively low survival rate. A correlation was also found between high DMS and enhanced immunotherapy efficacy in two immune checkpoint blocking treatment cohorts. To conclude, identifying DNA methylation regulation patterns may prove critical to understanding glioblastoma progression and differentiation, as well as future therapeutic targets.

SP1 transcriptionally activates NLRP6 inflammasome and induces immune evasion and radioresistance in glioma cells.

Glioma accounts for approximately 80% of all malignant brain tumors. This study aimed to investigate the interaction between specificity protein 1 (SP1) and NLR family pyrin domain containing 6 (NLRP6) and their roles in the activity of glioma cells. Differentially expressed genes in glioma were identified using transcriptome analysis tools, and a protein-protein-interaction network was performed based on the DEGs. SP1 and NLRP6 were abundantly expressed in glioma cells and indicated unfavorable prognosis of patients according to the GEO datasets. SP1could bind to the promoter of NLRP6 and induce its transcriptional activity. Downregulation of SP1 reduced proliferation, migration and invasion of glioma U87 cells in vitro as well as tumorigenesis in vivo. The malignancy of cells was restored after NLRP6 upregulation. Downregulation of SP1 in glioma cells also increased proliferation of CD8+ T cells and the immune activity in U87 cells, and it reduced the radioresistance of U87 cells. However, the immune evasion and radioresistance of glioma cells were restored upon NLRP6 upregulation. NLRP6 mediated the innate immune pathway through an ASC/caspase-1/IL-1ß axis. To conclude, this study suggested that SP1 interacts with NLRP6 inflammasome to enhance malignant behaviors, immune evasion and radioresistance in glioma cells.

Dissecting Prognosis Modules and Biomarkers in Glioblastoma Based on Weighted Gene Co-Expression Network Analysis.

INTRODUCTION: As one of the most prevalent and malignant brain cancers, glioblastoma multiforme (GBM) presents a poor prognosis and the molecular mechanisms remain poorly understood. Consequently, molecular research, including various biomarkers, is essential to exploit the occurrence and development of glioma. METHODS: Weighted gene co-expression network analysis (WGCNA) was used to construct gene co-expression modules and networks based on the Chinese Glioma Genome Atlas (CGGA) glioblastoma specimens. Then, protein-protein interaction (PPI) and gene ontology (GO) analyses were performed to mine hub genes. RT-PCR and immunohistochemistry were employed to examine the expression level of GRPR, CXCL5, and CXCL11 in glioma patients. RESULTS: We confirmed two gene modules by protein-protein interaction networks. Functional enrichment analysis was performed to identify the significance of gene modules. Prognostic biomarkers GRPR, CXCL5, and CXCL11 related to the survival time of GBM samples were mined in The Cancer Genome Atlas (TCGA) dataset. qRT-PCR revealed that GRPR, CXCL5, and CXCL11 led to a significant increase in GBM sample compared to control. CONCLUSION: In this study, we developed and confirmed three mRNA signatures (GRPR, CXCL5, and CXCL11) for evaluating overall survival in GBM patients. Our research assists in existing understanding of GBM diagnosis and prognosis.

Exosomal miR-199a-5p derived from endothelial cells attenuates apoptosis and inflammation in neural cells by inhibiting endoplasmic reticulum stress.

Remote ischemic post-conditioning (RIPostC) is a technique that can protect vital organs in an indirect manner, the effects of which are exerted by the long-distance exosome-mediated transfer of functional factors. In the current study, the possible mechanism driving the function of RIPostC was explored using an in vitro system by focusing on miR-199a-5p and its downstream effectors involved in endoplasmic reticulum (ER) stress. Human umbilical vein endothelial cells (HUVECs) were administrated with hypoxia/re-oxygenation (H/R) process and exosomes were collected from the H/R-treated HUVECs. The levels of miR-199a-5p in HUVECs and exosomes were detected. Afterwards, H/R-treated SH-SY5Y neural cells was incubated with H/R HUVEC-derived exosomes, and the effect on cell apoptosis, inflammation, and miR-199a-5p-mediated ER stress was assessed. Furthermore, the key role of miR-199a-5p suppression in the protection effect of HUVEC-derived exosomes was validated by transfecting neural cells with specific inhibitor. The results showed that H/R administration increased miR-199a-5p levels both in HUVECs and exosomes. The incubation of neural cells with exosomes suppressed cell apoptosis and inflammation, and induced the level of miR-199a-5p, which led to suppressed ER stress. Moreover, the transfection of miR-199a-5p inhibitor blocked the anti-H/R function of exosomes. Taken together, the findings outlined in the current study showed that the protection effect of HUVEC derived miR-199a-5p on neural cells was exerted via exosome transfer, which then suppressed the ER stress-induced apoptosis and inflammation by targeting BIP.

Low expression or hypermethylation of PLK2 might predict favorable prognosis for patients with glioblastoma multiforme.

BACKGROUND: As the most aggressive brain tumor, patients with glioblastoma multiforme (GBM) have a poor prognosis. Our purpose was to explore prognostic value of Polo-like kinase 2 (PLK2) in GBM, a member of the PLKs family. METHODS: The expression profile of PLK2 in GBM was obtained from The Cancer Genome Atlas database. The PLK2 expression in GBM was tested. Kaplan-Meier curves were generated to assess the association between PLK2 expression and overall survival (OS) in patients with GBM. Furthermore, to assess its prognostic significance in patients with primary GBM, we constructed univariate and multivariate Cox regression models. The association between PLK2 expression and its methylation was then performed. Differentially expressed genes correlated with PLK2 were identified by Pearson test and functional enrichment analysis was performed. RESULTS: Overall survival results showed that low PLK2 expression had a favorable prognosis of patients with GBM (P-value = 0.0022). Furthermore, PLK2 (HR = 0.449, 95% CI [0.243-0.830], P-value = 0.011) was positively associated with OS by multivariate Cox regression analysis. In cluster 5, DNA methylated PLK2 had the lowest expression, which implied that PLK2 expression might be affected by its DNA methylation status in GBM. PLK2 in CpG island methylation phenotype (G-CIMP) had lower expression than non G-CIMP group (P = 0.0077). Regression analysis showed that PLK2 expression was negatively correlated with its DNA methylation (P = 0.0062, Pearson r = -0.3855). Among all differentially expressed genes of GBM, CYGB (r = 0.5551; P < 0.0001), ISLR2 (r = 0.5126; P < 0.0001), RPP25 (r = 0.5333; P < 0.0001) and SOX2 (r = -0.4838; P < 0.0001) were strongly correlated with PLK2. Functional enrichment analysis results showed that these genes were enriched several biological processes or pathways that were associated with GBM. CONCLUSION: Polo-like kinase 2 expression is regulated by DNA methylation in GBM, and its low expression or hypermethylation could be considered to predict a favorable prognosis for patients with GBM.

Functional importance of the TGF-ß1/Smad3 signaling pathway in oxygen-glucose-deprived (OGD) microglia and rats with cerebral ischemia.

We investigated the transforming growth factor-b1 (TGF-ß1)/Smad3 signaling pathway in rats with cerebral ischemia and oxygen-glucose-deprived (OGD) microglia. Cerebral ischemia is a clinical condition that occurs when insufficient blood flows to the brain to maintain metabolic activity. TGF-ß1 is a well-known functional peptide that regulates cell differentiation, migration, proliferation, and apoptosis. In the current study, we determined the infarct size and TGF-ß1/Smad3 protein expression in stroke-induced rats. Apoptosis and TGF-ß1/Smad3 mRNA and protein expression were determined in transfected OGD human microglial cells. TGF-ß1 treatment resulted in smaller infarct regions than in control cells, whereas TGF-ß1 inhibitor treatment resulted in larger infarcts. The TGF-ß1-treated groups showed substantial TGF-ß1 and Smad3 expression by immunofluorescence compared to the controls. Apoptosis was significantly reduced in TGF-ß1- and Smad3-transfected cells, and an increased rate of apoptosis was observed in Smad3 or TGF-ß1 siRNA-transfected cells. TGF-ß1 and Smad3 mRNA and protein expression increased following TGF-ß1 and Smad3 transfection. Taken together, our experimental results show that Smad3 and TGF-ß1 play a protective role against ischemic stroke, as demonstrated by the reduced infarct size. Smad3 and TGF-ß1 expression was increased in cells transfected with TGF-ß1, whereas Smad3 and TGF-ß1 expression was increased in TGF-ß1 inhibitor-transfected cells.

[Retracted] Regulatory T cells exhibit neuroprotective effect in a mouse model of traumatic brain injury.

We would like to retract our article entitled 'Regulatory T cells exhibit neuroprotective effect in a mouse model of traumatic brain injury' published in Molecular Medicine Reports 14: 5556-5566, 2016. After careful consideration, we recognize that there was an undeclared conflict of interest on the part of certain of the authors. All the authors agree to this retraction. We sincerely apologize for any inconvenience that might result from the retraction of this article. [The original article was published in Molecular Medicine Reports 14: 5556-5566, 2016; DOI: 10.3892/mmr.2016.5954].

Globularifolin exerts anticancer effects on glioma U87 cells through inhibition of Akt/mTOR and MEK/ERK signaling pathways in vitro and inhibits tumor growth in vivo.

Gliomas are the most recurrently occurring primary malignancies in the central nervous system. Despite surgical interventions, chemo- and radiotherapy, the results are unfortunately poor. Therefore, there is pressing need to explore more effective and efficient treatment options for treatment of glioma. In the present study we determined the anticancer potential of globularifolin against human glioma U87 cell line and human astrocytes. The results showed that globularifolin exhibits an IC50 value of 7.5 µM against glioma U87 cells as against the IC50 of 65 µM against human astrocytes. The molecule exerted its anticancer activity through induction of apoptosis as evident from the Bid-, and Bax controlled cytochrome c and Omi/HtrA2 release, XIAP suppression, and caspase-9 and 3 signalling cascade. Additionally, it also caused cell cycle arrest of human glioma U87 cancer cells in the S phase of the cell cycle. Interestingly, globularifolin also caused significant inhibition of Akt/mTOR/p70S6K and MEK/ERK pathways. Globularifolin also inhibits cell migration and invasion by regulating the expression of matrix metalloproteinases (MMPs) in U87 glioma cells. We further investigated whether globularifolin exhibits the same effectiveness against glioma cell xenografts in nude mice in vivo and it was observed that globularifolin significantly reduced the tumor growth and volume in vivo indicating the potential of globularifolin as lead molecule for glioma chemotherapy.

Regulatory T cells exhibit neuroprotective effect in a mouse model of traumatic brain injury.

Traumatic brain injury (TBI) is a major health and socioeconomic problem as it is associated with high rates of mortality and morbidity worldwide. Regulatory T cells (Tregs) have been reported to reduce inflammatory response in several diseases, including myasthenia gravis, viral myocarditis and cerebral infarction. The present study investigated the role of Tregs in mediating neuro­protective effects in a mouse model of TBI. Initially, Treg levels were determined, and compared between the controlled cortical impact (CCI) model for moderate TBI and the sham group, by using flow cytometry and ELISA. Afterwards, the number of Tregs was upregulated (by injection) and downregulated (by depletion), respectively, to elucidate the effect of Tregs in the presence of an inflammatory reaction and a deficient neurological function and consequently, in the prognosis of TBI in the mouse. The expression of pro­inflammatory cytokines [tumor necrosis factor (TNF)­α, interleukin (IL)­1ß, IL­6)] and anti­inflammatory cytokines [IL­10, transforming growth factor (TGF)­ß] in blood and brain tissues was also measured in the five groups: Μice receiving a saline injection, mice experiencing Treg depletion, small­dose (SD Tregs, 1.25x105), and mice receiving different doses of Tregs: Moderate­dose (MD Tregs, 2.5x105) and large­dose (LD Tregs, 5x105), using ELISA and PCR. Co­cultures of Tregs and microglia were performed to evaluate the expression of pro­inflammatory cytokines and observe the interaction between the two types of cells. The regulation patterns in JNK­NF­κB pathway by Tregs were also evaluated by western blot analysis. Treg levels were significantly reduced in TBI mouse group on the 3rd day after TBI (P<0.05). In the mouse model of TBI, the expression of pro­inflammatory cytokines (TNF­α, IL­1ß, IL­6) was enhanced, while the expression of anti­inflammatory cytokines (IL­10, TGF­ß) was reduced (P<0.05). Tregs exhibited a suppressive effect on inflammatory reactions. In the MD group, the activation of microglia cells was markedly inhibited, compared to the activation in SD and LD groups. The expression of ERK1/2, JNK1/2/3 and NK­κB was significantly downregulated in the MD group. The results indicated that Tregs exhibited significant neuro­protective effects, suppressing pro­inflammatory responses and promoting tissue repair after TBI injury in the mouse, specifically by deactivating the JNK­NF­κB pathway. The results of the study show that Tregs potentially participates in neuro­therapeutic approaches for TBI.