Brain ischemic stroke is one of the most common causes of death and disability, currently has no efficient therapeutic strategy in clinic. Due to irreversible functional neurons loss and neural tissue injury, stem cell transplantation may be the most promising treatment approach. Neural stem cells (NSCs) as the special type of stem cells only exist in the nervous system, can differentiate into neurons, astrocytes, and oligodendrocytes, and have the abilities to compensate insufficient endogenous nerve cells and improve the inflammatory microenvironment of cell survival. In this review, we focused on the important role of NSCs therapy for brain ischemic stroke, mainly introduced the methods of optimizing the therapeutic efficacy of NSC transplantation, such as transfection and overexpression of specific genes, pretreatment of NSCs with inflammatory factors, and co-transplantation with cytokines. Next, we discussed the potential problems of NSC transplantation which seriously limited their rapid clinical transformation and application. Finally, we expected a new research topic in the field of stem cell research. Based on the bystander effect, exosomes derived from NSCs can overcome many of the risks and difficulties associated with cell therapy. Thus, as natural seed resource of nervous system, NSCs-based cell-free treatment is a newly therapy strategy, will play more important role in treating ischemic stroke in the future.

No abstract

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.

No abstract

Glioblastoma multiforme (GBM), the most frequently occurring malignant brain tumor in adults, remains mostly untreatable. Because of the heterogeneity of invasive gliomas and drug resistance associated with the tumor microenvironment, the prognosis is poor, and the survival rate of patients is low. Communication between GBMs and non-glioma cells in the tumor microenvironment plays a vital role in tumor growth and recurrence. Emerging data have suggested that neural stem cells (NSCs) in the subventricular zone (SVZ) are the cells-of-origin of gliomas, and SVZ NSC involvement is associated with the progression and recurrence of GBM. This review highlights the interaction between SVZ NSCs and gliomas, summarizes current findings on the crosstalk between gliomas and other non-glioma cells, and describes the links between SVZ NSCs and gliomas. We also discuss the role and mechanism of SVZ NSCs in glioblastoma, as well as the interventions targeting the SVZ and their therapeutic implications in glioblastoma. Taken together, understanding the biological mechanism of glioma-NSC interactions can lead to new therapeutic strategies for GBM.

JNK activity has been implicated in the malignant proliferation, invasion and drug‐resistance of glioma cells (GCs), but the molecular mechanisms underlying JNK activation are currently unknown. Here, we reported that MKK7, not MKK4, directly activates JNK in GCs and exerts oncogenic effects on tumor formation. Notably, MKK7 expression in glioma tissues was closely correlated with the grade of the glioma and JNK/c‐Jun activation. Mechanistically, MKK7 transcription critically depends on the complexes formed by HDAC4 and the transcriptional factors SP1 and Krüppel‐like factor‐5 (KLF5), wherein HDAC4 directly deacetylates both SP1 and KLF5 and synergistically upregulates MKK7 transcription through two SP1 sites located on its promoter. In contrast, the increases in acetylated‐SP1 and acetylated‐KLF5 after HDAC4 inhibition switched to transcriptionally suppress MKK7. Selective inhibition of HDAC4 by LMK235, siRNAs or blockage of SP1 and KLF5 by the ectopic dominant‐negative SP1 greatly reduced the malignant capacity of GCs. Furthermore, suppression of both MKK7 expression and JNK/c‐Jun activities was involved in the tumor‐growth inhibitory effects induced by LMK235 in U87‐xenograft mice. Interestingly, HDAC4 is highly expressed in glioma tissues, and the rate of HDAC4 nuclear import is closely correlated with glioma grade, as well as with MKK7 expression. Collectively, these findings demonstrated that highly expressed MKK7 contributes to JNK/c‐Jun signaling‐mediated glioma formation. MKK7 transcription, regulated by SP1 and KLF5, critically depends on HDAC4 activity, and inhibition of HDAC4 presents a potential strategy for suppressing the oncogenic roles of MKK7/JNK/c‐Jun signaling in GCs.

Our study demonstrated that neuritin plays a neuroprotective role on EBI after SAH by attenuating BBB disruption, brain edema and apoptosis.

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.