Elevated SLC3A2 associated with poor prognosis and enhanced malignancy in gliomas.

The role of SLC3A2, a gene implicated in disulfidptosis, has not been characterized in gliomas. This study aims to clarify the prognostic value of SLC3A2 and its influence on glioma. We evaluated the expression of SLC3A2 and its prognostic importance in gliomas using publicly accessible databases and our clinical glioma samples and with reliance on Meta and Cox regression analysis approaches. Functional enrichment analyses were performed to explore SLC3A2's function. Immune infiltration was evaluated using CIBERSORT, ssGSEA, and single-cell sequencing data. Additionally, Tumor immune dysfunction and exclusion (TIDE) and epithelial-mesenchymal transition scores were determined. CCK8, colony formation, migration, and invasion assays were utilized in vitro, and an orthotopic glioma xenograft model was employed in vivo, to investigate the role of SLC3A2 in gliomas. Bioinformatics analyses indicated high SLC3A2 expression correlates with adverse clinicopathological features and poor patient prognosis. Upregulated SLC3A2 influenced the tumor microenvironment by altering immune cell infiltration, particularly of macrophages, and tumor migration and invasion. SLC3A2 expression positively correlated with immune therapy indicators, including immune checkpoints and TIDE. Elevated SLC3A2 was revealed as an independent risk element for poor glioma prognosis through Cox regression analyses. In vitro experiments showed that reduced SLC3A2 expression decreased cell proliferation, migration, and invasion. In vivo, knockdown of SLC3A2 led to a reduction in tumor volume and prolonged survival in tumor-bearing mice. Therefore, SLC3A2 is a prognostic biomarker and associated with immune infiltration in gliomas.

Mendelian Randomization Analyses Accounting for Causal Effect of COVID-19 on Brain Imaging-Derived Phenotypes.

BACKGROUND: The coronavirus disease 2019 (COVID-19) has been a major challenge to global health and a financial burden. Little is known regarding the possible causal effects of COVID-19 on the macro- and micro-structures of the human brain. OBJECTIVE: To determine the causal links between susceptibility, hospitalization, and the severity of COVID-19 and brain imaging-derived phenotypes (IDPs). METHODS: Mendelian randomization (MR) analyses were performed to investigate the causal effect of three COVID-19 exposures (SARS-CoV-2 infection, hospitalized COVID-19, and critical COVID-19) on brain structure employing summary datasets of genome-wide association studies. RESULTS: In terms of cortical phenotypes, hospitalization due to COVID-19 was associated with a global decrease in the surface area (SA) of the cortex structure (ß= -624.77, 95% CI: -1227.88 to -21.66, p = 0.042). At the regional level, SARS-CoV-2 infection was found to have a nominally causal effect on the thickness (TH) of the postcentral region (ß= -0.004, 95% CI: -0.007 to -0.001, p = 0.01), as well as eight other IDPs. Hospitalized COVID-19 has a nominally causal relationship with TH of postcentral (ß= -0.004, 95% CI: -0.007 to -0.001, p = 0.01) and other 6 IDPs. The nominally causal effects of critical COVID-19 on TH of medial orbitofrontal (ß=0.004, 95% CI: 0.001to 0.007, p = 0.004) and other 7 IDPs were revealed. CONCLUSIONS: Our study provides compelling genetic evidence supporting causal relationships between three COVID-19 traits and brain IDPs. This discovery holds promise for enhancing predictions and interventions in brain imaging.

GPR37 expression as a prognostic marker in gliomas: a bioinformatics-based analysis.

BACKGROUND: Gliomas are the most frequently diagnosed primary brain tumors, and are associated with multiple molecular aberrations during their development and progression. GPR37 is an orphan G protein-coupled receptor (GPCR) that is implicated in different physiological pathways in the brain, and has been linked to various malignancies. The aim of this study was to explore the relationship between GPR37 gene expression and the clinicopathological factors, patient prognosis, tumor-infiltrating immune cell signature GSEA and methylation levels in glioma. METHODS: We explored the diagnostic value, clinical relevance, and molecular function of GPR37 in glioma using TCGA, STRING, cBioPortal, Tumor Immunity Estimation Resource (TIMER) database and MethSurv databases. Besides, the "ssGSEA" algorithm was conducted to estimate immune cells infiltration abundance, with 'ggplot2' package visualizing the results. Immunohistochemical staining of clinical samples were used to verify the speculations of bioinformatics analysis. RESULTS: GPR37 expression was significantly higher in the glioma tissues compared to the normal brain tissues, and was linked to poor prognosis. Functional annotation of GPR37 showed enrichment of ether lipid metabolism, fat digestion and absorption, and histidine metabolism. In addition, GSEA showed that GPR37 was positively correlated to the positive regulation of macrophage derived foam cell differentiation, negative regulation of T cell receptor signaling pathway, neuroactive ligand receptor interaction, calcium signaling pathway, and negatively associated with immunoglobulin complex, immunoglobulin complex circulating, ribosome and spliceosome mediated by circulating immunoglobulin etc. TIMER2.0 and ssGSEA showed that GPR37 expression was significantly associated with the infiltration of T cells, CD8 T cell, eosinophils, macrophages, neutrophils, NK CD56dim cells, NK cells, plasmacytoid DCs (pDCs), T helper cells and T effector memory (Tem) cells. In addition, high GPR37 expression was positively correlated with increased infiltration of M2 macrophages, which in turn was associated with poor prognosis. Furthermore, GPR37 was positively correlated with various immune checkpoints (ICPs). Finally, hypomethylation of the GPR37 promoter was associated with its high expression levels and poor prognosis in glioma. CONCLUSION: GPR37 had diagnostic and prognostic value in glioma. The possible biological mechanisms of GPR37 provide novel insights into the clinical diagnosis and treatment of glioma.

Comprehensive analysis of the prognostic and immunological signature of eight Tripartitemotif (TRIM) family molecules in human gliomas.

BACKGROUND: TRIM family molecules have been identified as being involved in the tumor progression of various cancer types. Increasingly, experimental evidence indicates that some of TRIM family molecules are implicated in glioma tumorigenesis. However, the diverse genomic changes, prognostic values and immunological landscapes of TRIM family of molecules have yet to be fully determined in glioma. METHODS: In our study, employing the comprehensive bioinformatics tools, we evaluated the unique functions of 8 TRIM members including TRIM5/17/21/22/24/28/34/47 in gliomas. RESULTS: The expression levels of 7 TRIM members (TRIM5/21/22/24/28/34/47) were higher in glioma as well as its diverse cancer subtypes than in normal tissues, whereas the expression level of TRIM17 was the opposite, lower in the former than in the latter. In addition, survival analysis revealed that the high expression profiles of TRIM5/21/22/24/28/34/47 were associated with poor overall survival (OS), disease-specific survival (DSS) and progress-free interval (PFI) in glioma patients, whereas TRIM17 displayed adverse outcomes. Moreover, the 8 TRIM molecules expression as well as methylation profiles remarkably correlated with different WHO grades. And genetic alterations, including mutations and copy number alterations (CNAs), in the TRIM family were correlated with longer OS, DSS and progress-free survival (PFS) in glioma patients. Furthermore, through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis results of these 8 molecules and their related genes, we found that these molecules may change the immune infiltration of the tumor microenvironment and regulate the expression of immune checkpoint molecules (ICMs), affecting the occurrence and development of gliomas. The correlation analyses between the 8 TRIM molecules and TMB (tumor mutational burden)/MSI (microsatellite instability)/ICMs discovered that as the expression level of TRIM5/21/22/24/28/34/47 increased, the TMB score also increased significantly, while TRIM17 showed an opposite outcome. Further, a 6-gene signature (TRIM 5/17/21/28/34/47) for predicting overall survival (OS) in gliomas was built by using the least absolute shrinkage and selection operator (LASSO) regression, and the survival and time-dependent ROC analyses all were found to perform well in testing and validation cohorts. Results of multivariate COX regression analysis showed that TRIM5/28 are both expected to become independent risk predictors to guide clinical treatment. CONCLUSION: In general, the results indicate that TRIM5/17/21/22/24/28/34/47 might exert a crucial influence on gliomas tumorigenesis and might be putative prognostic markers and therapeutic targets for glioma patients.

Elevated LILRB1 expression predicts poor prognosis and is associated with tumor immune infiltration in patients with glioma.

BACKGROUND: Leukocyte immunoglobulin-like receptor subfamily B1 (LILRB1) is regarded as an inhibitory molecule. However, the importance of LILRB1 expression in glioma has not yet been determined. This investigation examined the immunological signature, clinicopathological importance and prognostic value of LILRB1 expression in glioma. METHODS: We used data from the UCSC XENA database, the Cancer Genome Atlas (TCGA) database, the Chinese Glioma Genome Atlas (CGGA) database, the STRING database, the MEXPRESS database and our clinical glioma samples to perform bioinformatic analysis and used vitro experiments to examine the predictive value and potential biological roles of LILRB1 in glioma. RESULTS: Higher LILRB1 expression was considerably present in the higher WHO grade glioma group and was linked to a poorer prognosis in patients with glioma. Gene set enrichment analysis (GSEA) revealed that LILRB1 was positively correlated with the JAK/STAT signaling pathway. LILRB1 combined with tumor mutational burden (TMB) and microsatellite instability (MSI) may be a promising indicator for the effectiveness of immunotherapy in patients with glioma. Increased LILRB1 expression was positively linked with the hypomethylation, M2 macrophage infiltration, immune checkpoints (ICPs) and M2 macrophage makers. Univariate and multivariate Cox regression analyses determined that increased LILRB1 expression was a standalone causal factor for glioma. Vitro experiments determined that LILRB1 positively enhanced the proliferation, migration and invasion in glioma cells. MRI images demonstrated that higher LILRB1 expression was related with larger tumor volume in patients with glioma. CONCLUSION: Dysregulation of LILRB1 in glioma is correlated with immune infiltration and is a standalone causal factor for glioma.

Lipidomics of the erythrocyte membrane and network pharmacology to explore the mechanism of mangiferin from Anemarrhenae rhizoma in treating type 2 diabetes mellitus rats.

Mangiferin, a natural C-glucoside xanthone, is one of the major bioactive ingredients derived from the dry rhizome of Anemarrhenae rhizome, which has been reported to exhibit various pharmacological effects, including anti-oxidant, anti-inflammatory, anti-fatty liver, anti-metabolic syndrome, and anti-diabetic. However, the precise molecular mechanisms underlying its impact on phospholipid metabolism in the erythrocyte membrane of type 2 diabetes mellitus (T2DM) remain unclear. The present research aimed to evaluate the effects of mangiferin on glucose and lipid metabolism in T2DM model rats and discuss the relationship between lipid metabolites and potential targets involved in the hypoglycemic effects by integrating lipidomics and network pharmacology method. After 8 consecutive weeks of treatment with mangiferin, the T2DM model rats exhibited significant improvements in several biochemical indices and cytokines, including fasting blood glucose (FBG) levels after 12 h of fasting, fasting insulin level (FINS), total cholesterol (T-CHO), triacylglycerols (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), homeostasis model assessment of insulin resistance (HMOA-IR), TNF-α and IL-6. A total of 22 differential lipid metabolites were selected from erythrocyte membrane phospholipids, which were closely associated with the processes of T2DM. These metabolites mainly belonged to glycerophospholipid metabolism and sphingolipid metabolism. Based on network pharmacology analysis, 22 genes were recognized as the potential targets of mangiferin against diabetes. Moreover, molecular docking analysis revealed that the targets of TNF, CASP3, PTGS2, MMP9, RELA, PLA2G2A, PPARA, and NOS3 could be involved in the modulation of inflammatory signaling pathways and arachidonic acid (AA) metabolism to improve IR and hyperglycemia. The combination of immunohistochemical staining and PCR showed that mangiferin could treat T2DM by regulating the expression of PPARγ protein and NF-κB mRNA expression to impact glycerophospholipids (GPs) and AA metabolism. The present study showed that mangiferin might alleviate IR and hyperglycemia of T2DM model rats via multiple targets and multiple pathways to adjust their phospholipid metabolism, which may be the underlying mechanism for mangiferin in the treatment of T2DM.

PRMT6-CDC20 facilitates glioblastoma progression via the degradation of CDKN1B.

PRMT6, a type I arginine methyltransferase, di-methylates the arginine residues of both histones and non-histones asymmetrically. Increasing evidence indicates that PRMT6 plays a tumor mediator involved in human malignancies. Here, we aim to uncover the essential role and underlying mechanisms of PRMT6 in promoting glioblastoma (GBM) proliferation. Investigation of PRMT6 expression in glioma tissues demonstrated that PRMT6 is overexpressed, and elevated expression of PRMT6 is negatively correlated with poor prognosis in glioma/GBM patients. Silencing PRMT6 inhibited GBM cell proliferation and induced cell cycle arrest at the G0/G1 phase, while overexpressing PRMT6 had opposite results. Further, we found that PRMT6 attenuates the protein stability of CDKN1B by promoting its degradation. Subsequent mechanistic investigations showed that PRMT6 maintains the transcription of CDC20 by activating histone methylation mark (H3R2me2a), and CDC20 interacts with and destabilizes CDKN1B. Rescue experimental results confirmed that PRMT6 promotes the ubiquitinated degradation of CDKN1B and cell proliferation via CDC20. We also verified that the PRMT6 inhibitor (EPZ020411) could attenuate the proliferative effect of GBM cells. Our findings illustrate that PRMT6, an epigenetic mediator, promotes CDC20 transcription via H3R2me2a to mediate the degradation of CDKN1B to facilitate GBM progression. Targeting PRMT6-CDC20-CDKN1B axis might be a promising therapeutic strategy for GBM.

Primary angioleiomyoma of right frontal cranial base with intracranial and extracranial communication.

INTRODUCTION: Primary intracranial angioleiomyoma (ALM) is quite rare and ALM of the adolescent is even rarer. To date, only three cases of adolescents have been reported. MATERIAL AND METHODS: We carefully introduced a new location of intracranial ALM in an adolescent. The clinical, pathological and imaging features of intracranial ALM were described in detail and published literature was reviewed. RESULTS: To our best knowledge, we presented the fourth primary intracranial ALM of adolescent and the first ALM of the right frontal cranial base with intracranial and extracranial communication. We not only summarize the generalities of ALM but also illustrate the difference between adult and adolescent ALM in the aspects of gender and age predominance, etiology, common location and pathologic subtype. CONCLUSIONS: We reported the first ALM of the right frontal cranial base with intracranial and extracranial communication of an adolescent with a good prognosis. We also summarize the generalities of ALM and illustrate the difference between adult and adolescent ALM. Future investigation of control study with large patient cohorts is needed for both adult and adolescent ALM to compare the difference between them.

Paeoniflorin Inhibits EMT and Angiogenesis in Human Glioblastoma via K63-Linked C-Met Polyubiquitination-Dependent Autophagic Degradation.

Epithelial-to-mesenchymal transition (EMT) and angiogenesis have emerged as two pivotal events in cancer progression. Paeoniflorin has been widely studied in experimental models and clinical trials for cancer treatment because of its anti-cancer property. However, the underlying mechanisms of paeoniflorin in EMT and angiogenesis in glioblastoma was not fully elucidated. The present study aimed to investigate whether paeoniflorin inhibits EMT and angiogenesis, which involving c-Met suppression, while exploring the potential ways of c-Met degradation. In our study, we found that paeoniflorin inhibited EMT via downregulating c-Met signaling in glioblastoma cells. Furthermore, overexpressing c-Met in glioblastoma cells abolished the effects of paeoniflorin on EMT. Moreover, paeoniflorin showed anti-angiogenic effects by suppressing cell proliferation, migration, invasion and tube formation through downregulating c-Met in human umbilical vein endothelial cells (HUVECs). And c-Met overexpression in HUVECs offset the effects of paeoniflorin on angiogenesis. Additionally, paeoniflorin induced autophagy activation involving mTOR/P70S6K/S6 signaling and promoted c-Met autophagic degradation, a process dependent on K63-linked c-Met polyubiquitination. Finally, paeoniflorin suppressed mesenchymal makers (snail, vimentin, N-cadherin) and inhibited angiogenesis via the identical mechanism in an orthotopic xenograft mouse model. The in vitro and in vivo experiments showed that paeoniflorin treatment inhibited EMT, angiogenesis and activated autophagy. What's more, for the first time, we identified c-Met may be a potential target of paeoniflorin and demonstrated paeoniflorin downregulated c-Met via K63-linked c-Met polyubiquitination-dependent autophagic degradation. Collectively, these findings indicated that paeoniflorin inhibits EMT and angiogenesis via K63-linked c-Met polyubiquitination-dependent autophagic degradation in human glioblastoma.

Echinacoside (ECH) suppresses proliferation, migration, and invasion of human glioblastoma cells by inhibiting Skp2-triggered epithelial-mesenchymal transition (EMT).

BACKGROUND: Echinacoside (ECH) is a phenylethanoid extracted from the stems of Cistanches salsa, an herb used in Chinese medicine formulations, and is effective against glioblastoma multiforme (GBM). Epithelial-mesenchymal transition (EMT) is the cornerstone of tumorigenesis and metastasis, and increases the malignant behavior of GBM cells. The S phase kinase-related protein 2 (skp2), an oncoprotein associated with EMT, is highly expressed in GBM and significantly associated with drug resistance, tumor grade and dismal prognosis. The aim of this study was to explore the inhibitory effects of ECH against GBM development and skp2-induced EMT. METHODS: CCK-8, EdU incorporation, transwell, colony formation and sphere formation assays were used to determine the effects of ECH on GBM cell viability, proliferation, migration and invasion in vitro. The in vivo anti-glioma effects of ECH were examined using a U87 xenograft model. The expression levels of skp2 protein, EMT-associated markers (vimentin and snail) and stemness markers (Nestin and sox2) were analyzed by immunofluorescence staining and western blotting experiments. RESULTS: ECH suppressed the proliferation, invasiveness and migration of GBM cells in vitro, as well as the growth of U87 xenograft in vivo. In addition, ECH downregulated the skp2 protein, EMT-related markers (vimentin and snail) and stemness markers (sox2 and Nestin). The inhibitory effects of ECH were augmented in the skp2-knockdown GBM cells, and reversed in cells with ectopic expression of skp2. CONCLUSION: ECH inhibits glioma development by suppressing skp2-induced EMT of GBM cells.

Prognostic and Immunological Role of PPP1R14A as a Pan-Cancer Analysis Candidate.

Despite emerging evidence revealing the remarkable roles of protein phosphatase 1 regulatory inhibitor subunit 14A (PPP1R14A) in cancer tumorigenesis and progression, no pan-cancer analysis is available. A comprehensive investigation of the potential carcinogenic mechanism of PPP1R14A across 33 tumors using bioinformatic techniques is reported for the first time. PPP1R14A is downregulated in major malignancies, and there is a significant correlation between the PPP1R14A expression and the prognosis of patients. The high expression of PPP1R14A in most cases was associated with poor overall survival (OS), disease-specific survival (DSS), and progress-free interval (PFI) across patients with various malignant tumors, including adrenocortical carcinoma (ACC) and bladder urothelial carcinoma (BLCA), indicated through pan-cancer survival analysis. Receiver operating characteristic (ROC) analysis subsequently exhibited that the molecule has high reference significance in diagnosing a variety of cancers. The frequency of PPP1R14A genetic changes including genetic mutations and copy number alterations (CNAs) in uterine carcinosarcoma reached 16.07%, and these alterations brought misfortune to the survival and prognosis of cancer patients. In addition, methylation within the promoter region of PPP1R14A DNA was enhanced in a majority of cancers. Downregulated phosphorylation levels of phosphorylation sites including S26, T38, and others in most cases took place in several tumors, such as breast cancer and colon cancer. PPP1R14A remarkably correlated with the levels of infiltrating cells and immune checkpoint genes. Our research on the carcinogenic effect of PPP1R14A in different tumors is comprehensively summarized and analyzed and provides a theoretical basis for future therapeutic and immunotherapy strategies.

3BDO inhibits the proliferation, epithelial-mesenchymal transition (EMT), and stemness via suppressing survivin in human glioblastoma cells.

Background: Glioblastoma (GBM) is a tumor of the central nervous system with an extremely poor prognosis. Stemness and EMT play important roles in GBM progression. 3-benzyl-5-((2-nitrophenoxy) methyl) dihydrofuran-2(3H)-one (3BDO), an autophagy inhibitor, has been reported to exert anti-cancer activities on lung carcinoma. However, the effects of 3BDO on GBM remain unknown. Therefore, the purpose of this study was to explore the effects of 3BDO on GBM and to investigate the underlying molecular mechanisms. Method: CCK-8 experiments and clone formation assays were conducted to determine the level of cell proliferation. Transwell assay was conducted to examine cell migration and invasion abilities. Western blotting and immunofluorescence staining were used to analyze protein expression levels. A xenograft mouse model was used to evaluate the effect of 3BDO in vivo. Results: We found that 3BDO inhibited U87 and U251 cell proliferation in a dose-dependent manner. Additionally, 3BDO decreased the degree of sphere formation and levels of stemness markers (sox2, nestin, and CD133) in GSCs. 3BDO also inhibited migration and invasion abilities and suppressed EMT markers (N-cadherin, vimentin, and snail) in GBM cells. Moreover, we found that 3BDO downregulated the expression of survivin in both GBM cells (U87, U251) and GSCs. Furthermore, overexpression of survivin decreased the therapeutic effect of 3BDO on EMT, invasion, migration, and proliferation of GBM cells, as well as decreased the stemness of GSCs. Finally, we demonstrated that 3BDO could inhibit tumor growth in a tumor xenograft mouse model constructed using U87 cells. Similar to the in vitro findings, 3BDO decreased the expression of survivin, EMT makers, and the degree of stemness in vivo. Conclusions: Our results demonstrate that 3BDO can repress GBM both in vitro and in vivo via downregulating survivin-mediated stemness and EMT.

Effects of DISC1 on Alzheimer's disease cell models assessed by iTRAQ proteomics analysis.

Alzheimer's disease (AD) is a form of neurodegenerative disease in the elderly with no cure at present. In a previous study, we found that the scaffold protein, disrupted in Schizophrenia 1 (DISC1) is down-regulated in the AD brains, and ectopic expression of DISC1 can delay the progression of AD by protecting synaptic plasticity and down-regulating BACE1. However, the underlying mechanisms remain not to be elucidated. In the present study, we compared the proteomes of normal and DISC1high AD cells expressing the amyloid precursor protein (APP) using isobaric tag for relative and absolute quantitation (iTRAQ) and mass spectrometry (MS). The differentially expressed proteins (DEPs) were identified, and the protein-protein interaction (PPI) network was constructed to identify the interacting partners of DISC1. Based on the interaction scores, NDE1, GRM3, PTGER3 and KATNA1 were identified as functionally or physically related to DISC1, and may therefore regulate AD development. The DEPs were functionally annotated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases with the DAVID software, and the Non-supervised Orthologous Groups (eggNOG) database was used to determine their evolutionary relationships. The DEPs were significantly enriched in microtubules and mitochondria-related pathways. Gene set enrichment analysis (GSEA) was performed to identify genes and pathways that are activated when DISC1 is overexpressed. Our findings provide novel insights into the regulatory mechanisms underlying DISC1 function in AD.

Hsa_circ_0076931 suppresses malignant biological properties, down-regulates miR-6760-3p through direct binding, and up-regulates CCBE1 in glioma.

The function of circular RNAs (circRNAs) in gliomas is as yet unknown. The present study explored role of hsa_circ_0076931 in glioma. circRNA expression profiles were identified via RNA-seq followed by qRT-PCR validation in three pairs of glioma and normal brain tissues (NBT). The function of hsa_circ_0076931 was investigated in vitro using cell lines as well as in vivo using a xenograft tumor. Hsa_circ_0076931 was up-regulated by overexpression and an mRNA profile compared with wild-type was identified by RNA-seq. The relationship between miR-6760-3p and hsa_circ_0076931 or CCBE1 was confirmed via luciferase reporter or AGO2-RIP assays. A total of 507 circRNAs were identified in glioma tissues that were differentially expressed compared with that in NBT, and the sequencing data were deposited in BioProject (ID: PRJNA746438). Hsa_circ_0007694 and hsa_circ_0008016 were memorably increased whereas hsa_circ_0076931 and hsa_circ_0076948 decreased in glioma compared with those in NBT. Additionally, hsa_circ_0076931 expression was negatively correlated with histological grade. Overexpression of hsa_circ_0076931 inhibited proliferation, migration, and invasion while promoting apoptosis of glioma cells. A total of 4383 and 537 aberrantly expressed genes were identified between the hsa_circ_0076931-overexpressed and control groups in H4 and U118-MG cells, respectively; the sequencing data were deposited in BioProject (ID: PRJNA746438). These differentially expressed genes were mainly enriched in cancer-related pathways. In addition, elevated hsa_circ_0076931 levels induced the expression of CCBE1 while suppressing miR-6760-3p expression. miR-6760-3p can bind to hsa_circ_0076931. The experimental evidence supports using hsa_circ_0076931 as a marker for glioma and to help prevent malignant progression. The mechanism might be relevant to miR-6760-3p and CCBE1.

Deficiency of TRIM32 Impairs Motor Function and Purkinje Cells in Mid-Aged Mice.

Proper functioning of the cerebellum is crucial to motor balance and coordination in adult mammals. Purkinje cells (PCs), the sole output neurons of the cerebellar cortex, play essential roles in cerebellar motor function. Tripartite motif-containing protein 32 (TRIM32) is an E3 ubiquitin ligase that is involved in balance activities of neurogenesis in the subventricular zone of the mammalian brain and in the development of many nervous system diseases, such as Alzheimer's disease, autism spectrum disorder, attention deficit hyperactivity disorder. However, the role of TRIM32 in cerebellar motor function has never been examined. In this study we found that motor balance and coordination of mid-aged TRIM32 deficient mice were poorer than those of wild-type littermates. Immunohistochemical staining was performed to assess cerebella morphology and TRIM32 expression in PCs. Golgi staining showed that the extent of dendritic arborization and dendritic spine density of PCs were decreased in the absence of TRIM32. The loss of TRIM32 was also associated with a decrease in the number of synapses between parallel fibers and PCs, and in synapses between climbing fibers and PCs. In addition, deficiency of TRIM32 decreased Type I inositol 1,4,5-trisphosphate 5-phosphatase (INPP5A) levels in cerebellum. Overall, this study is the first to elucidate a role of TRIM32 in cerebellar motor function and a possible mechanism, thereby highlighting the importance of TRIM32 in the cerebellum.

Elevated TYROBP expression predicts poor prognosis and high tumor immune infiltration in patients with low-grade glioma.

BACKGROUND: Tyrosine protein tyrosine kinase binding protein (TYROBP) binds non-covalently to activated receptors on the surface of various immune cells, and mediates signal transduction and cellular activation. It is dysregulated in various malignancies, although little is known regarding its role in low-grade glioma. The aim of this study is to explore the clinicopathological significance, prognostic value and immune signature of TYROBP expression in low-grade glioma (LGG). METHODS: The differentially expressed genes (DEGs) between glioma samples and normal tissues were identified from two GEO microarray datasets using the limma package. The DEGs overlapping across both datasets were functionally annotated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. STRING database was used to establish the protein-protein interaction (PPI) of the DEGs. The PPI network was visualized by Cytoscape and cytoHubba, and the core module and hub genes were identified. The expression profile of TYROBP and patient survival were validated in the Oncomine, GEPIA2 and CGGA databases. The correlation between TYROBP expression and the clinicopathologic characteristics were evaluated. Gene Set Enrichment Analysis (GSEA) and single-sample GSEA (ssGSEA) were performed by R based on the LGG data from TCGA. The TIMER2.0 database was used to determine the correlation between TYROBP expression and tumor immune infiltrating cells in the LGG patients. Univariate and multivariate Cox regression analyses were performed to determine the prognostic impact of clinicopathological factors via TCGA database. RESULTS: Sixty-two overlapping DEGs were identified in the 2 datasets, and were mainly enriched in the response to wounding, focal adhesion, GTPase activity and Parkinson disease pathways. TYROBP was identified through the PPI network and cytoHubba. TYROBP expression levels were significantly higher in the LGG tissues compared to the normal tissues, and was associated with worse prognosis and poor clinicopathological parameters. In addition, GSEA showed that TYROBP was positively correlated to neutrophil chemotaxis, macrophage activation, chemokine signaling pathway, JAK-STAT signaling pathway, and negatively associated with gamma aminobutyric acid signaling pathway, neurotransmitter transport, neuroactive ligand receptor intersection etc. TIMER2.0 and ssGSEA showed that TYROBP expression was significantly associated with the infiltration of neutrophils, macrophages, myeloid dendritic cells and monocytes. The infiltration of the M2 phenotype macrophages, cancer-associated fibroblasts and myeloid dendritic cells correlated to worse prognosis in LGG patients. Finally, multivariate analysis showed that elevated TYROBP expression is an independent risk factor for LGG. CONCLUSION: TYROBP is dysregulated in LGG and correlates with immune infiltration. It is a potential therapeutic target and prognostic marker for LGG.

LHPP impedes energy metabolism by inducing ubiquitin-mediated degradation of PKM2 in glioblastoma.

Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) is a new-found tumor suppressor in a variety of tumors. While, it is still unknown about its role in glioma. In this study, we found that LHPP is abnormally decreasing or absent in glioblastoma, and the low expression of LHPP is associated with poor median survival in glioma patients. Functional assay revealed that LHPP-overexpression significantly inhibited U87MG and U118MG growth in vitro and in vivo. As to the mechanism, mass-spectrometric analysis indicated that the LHPP interacting proteins were mainly enriched in regulation of energy metabolism, including Carbon metabolism, Oxidative phosphorylation, and Glycolysis. Seahorse assay and metabolites detection confirmed that LHPP-overexpression obviously impeded glycolysis and respiration in U87MG and U118MG cells. For the further study, western blot assay showed that the protein level of PKM2 at dimeric, tetrameric, and total protein, were all decreased significantly, and its enzymatic activity was decreased as well. ChIP and RNAseq integrated analysis indicated that the decreased protein level of PKM2 was independent of PKM2 transcription, and LHPP did not reprogram transcription level of metabolic genome. Co-IP and immunofluorescence assay manifested that LHPP interacted with PKM2, and this interaction interfered the protein stability, then induced ubiquitin-mediated degradation of PKM2. Rescue assay confirmed that restoring the expression of PKM2 effectively reversed the restrained energy metabolism and the inhibited cancer cell growth caused by LHPP-overexpression in U87MG and U118MG cells. Taking together, we demonstrated that LHPP impedes the glycolysis and respiration during energy metabolic process via inducing ubiquitin-mediated degradation of PKM2, thus inhibits the growth of glioblastoma.

Clemastine attenuates AD-like pathology in an AD model mouse via enhancing mTOR-mediated autophagy.

Alzheimer's disease (AD) is a neurodegenerative disorder with limited available drugs for treatment. Enhancing autophagy attenuates AD pathology in various AD model mice. Thus, development of potential drugs which enhance autophagy may bring beneficial effects in AD therapy. In the present study, we show clemastine, a first-generation histamine H1R antagonist and being originally marketed for the treatment of allergic rhinitis, ameliorates AD pathogenesis in APP/PS1 transgenic mice. Chronic treatment with clemastine orally reduced amyloid-ß (Aß) load, neuroinflammation and cognitive deficits of APP/PS1 transgenic mice. Clemastine decreases Aß generation via reducing the levels of BACE1, CTFs of APP. Mechanistically, clemastine enhances autophagy concomitant with a suppression of mTOR signaling. Therefore, we propose that clemastine attenuates AD pathology via enhancing mTOR-mediated autophagy.

Clemastine promotes recovery of neural function and suppresses neuronal apoptosis by restoring balance of pro-inflammatory mediators in an experimental model of intracerebral hemorrhage.

Intracerebral hemorrhage (ICH) represents a common acute cerebrovascular event that imparts high rates of disability. The microglia-mediated inflammatory response is a critical factor in determining cerebral damage post-ICH. Clemastine (CLM) is a histamine receptor H1 (HRH1) antagonist that has been shown to modulate the inflammatory response. However, the effects of CLM on ICH and the underlying mechanism remain to be determined. This investigation reveals that CLM resulted in reduction of cerebral hematoma volume, decreased cerebral edema and lower rates of neuronal apoptosis as well as improved behavioral scores in an acute ICH murine model. CLM treatment was noted to decrease pro-inflammatory effectors and increased anti-inflammatory effectors post-ICH. In addition, CLM reduced the deleterious effects of activated microglia on neurons in a transwell co-culture system. Our findings show that CLM likely mediates its therapeutic effect through inhibition of microglia-induced inflammatory response and apoptosis, thereby enhancing restoration of neuronal function.

A low MW inhibitor of CD44 dimerization for the treatment of glioblastoma.

BACKGROUND AND PURPOSE: As a hallmark of glioblastoma multiforme (GBM), CD44 plays a crucial role in promoting glioblastoma stem cell (GSC) stemness phenotypes and multiple drug resistance. The therapeutic potential of CD44 has been validated by the clinical successes of several CD44 inhibitors, including antibodies and hyaluronan-related drugs. EXPERIMENTAL APPROACH: We used systemsDock software to predict verbascoside as a candidate CD44 inhibitor. Microscale thermophoresis was used to confirm the interaction between CD44 and verbascoside. Four glioblastoma cell lines and a patient-derived glioblastoma cell line were used to test the influences of verbascoside on glioblastoma. CD44-overexpressing and CD44-knockout cell lines were also used. Real-time quantitative PCR and western blot analyses were performed. A xenograft mouse model was used to test verbascoside. KEY RESULTS: Verbascoside bound to CD44 and suppressed its dimerization. By inhibiting CD44 dimerization, verbascoside decreased the release of the CD44 intracellular domain (CD44ICD) and suppressed the expression of CD44 downstream genes. Verbascoside treatment suppressed the stemness phenotypes of cells with high CD44 expression. In a mouse model of glioma, verbascoside treatment highly reduced the growth of intracranial tumours and inhibited CD44ICD release. Both stem cell marker and mesenchymal GBM subtype marker genes were down-regulated in verbascoside-treated mice. CONCLUSION AND IMPLICATIONS: Verbascoside suppressed growth of glioblastoma cells by inhibiting CD44 dimerization. Stem cell-like cell properties and tumour cell growth were also suppressed by verbascoside, both in vitro and in vivo. Verbascoside significantly prolonged survival of xenografted mice.