NLRP3 inflammasome inhibitor ameliorates ischemic stroke by reprogramming the phenotype of microglia/macrophage in a murine model of distal middle cerebral artery occlusion.

Stroke is one of the leading causes of death and disability worldwide. NLRP3 inflammasome has an essential role in the neuropathology of stroke. Recent studies report that shifting the microglial M1 phenotype to the M2 phenotype protects against ischemic stroke. In the present study, the precise effects of Tranilast, a NLPR3 inflammasome inhibitor, on stroke were evaluated. We established a murine model of distal middle cerebral artery occlusion (dMCAO) and administered Tranilast to dMCAO-induced stroke mice. The NLRP3 level, caspase 1 activity, and infarct volume stroke mice were measured. The sensorimotor function, pro-inflammatory cytokine production, and M1/M2 marker expression were measured. The M1 phenotype was induced by treatment of BV2 microglia with lipopolysacharide and interferon γ, and these BV-2 cells were further treated with Tranilast. The expression of CD16 and CD206 was monitored. dMCAO increased the NLRP3 expression and enhanced caspase 1 activity. Tranilast treatment significantly decreased the infarct volume, improved sensorimotor function, and suppressed the production of inflammatory cytokines in stroke mice. Moreover, Tranilast decreased the M1 marker level while promoting the expression of M2 markers. In summary, our findings suggest that Tranilast ameliorates ischemic stroke through stimulating M2 polarization of microglia.

ATRX-dependent SVCT2 mediates macrophage infiltration in the glioblastoma xenograft model.

The α thalassemia/mental retardation syndrome X-linked (ATRX) mutation impairs DNA damage repair in glioblastoma (GBM), making these cells more susceptible to treatment, which may contribute to the survival advantage in patients with GBM containing ATRX mutations. To better understand the role of ATRX in GBM, genes correlated with ATRX expression were screened in the Cancer Genome Atlas (702 cases) and Chinese Glioma Genome Atlas (325 cases) databases. Sodium-vitamin C cotransporter 2 (SVCT2) was the most positively correlated gene with ATRX expression. ATRX (about 1.99-fold) and SVCT2 (about 2.25-fold) were upregulated in GBM tissues from 40 patients compared with normal brain tissues from 23 subjects. ShSVCT2 transfection did not alter the in vitro viability of GL261 cells. At the same time, it could inhibit the proliferation of GL261 cells in the orthotopic transplantation model with diminished infiltrating macrophages (CD45highCD11b+), downregulated chemokine (C-C motif) ligand 2 (Ccl2), Ccl4, C-X-C motif chemokine ligand 1 (Cxcl1), and Cxcl15 expression, and decreased p-IκBα and p-c-Jun expression. Effect of ShSVCT2 transfection could be reversed by overexpression of SVCT2. siRNA interference of ATRX-dependent SVCT2 signal with shSVCT2 could inhibit tumor cell proliferation in Glu261-LuNeo xenograft tumor model with more survival advantage, probably by the inhibited macrophage chemotaxis. These results indicate that ATRX-dependent SVCT2-mediated chemokine-induced macrophage infiltration is regulated by the NF-κB pathway, which could be considered as treatment targets.NEW & NOTEWORTHY This study demonstrates that interference of ATRX-dependent SVCT2-mediated chemokine-induced macrophage infiltration could inhibit tumor cell proliferation in the GBM cell line-derived xenograft model. ATRX and SVCT2 are potential treatment targets identified in this study.

Phosphatidylinositol 3,4,5-Trisphosphate-Dependent Rac Exchanger 2 Protein Facilitates Glioma Progression via Akt and Stat3 Signaling.

Glioblastoma multiforme (GBM) is the recognized as the most aggressive brain tumor with poor prognosis and low 1-year and 5-year survival rate. The treatment methods for GBM are limited and inefficient, and novel strategies for GBM treatment are urgently warranted. MiR-338-3p is described as a tumor suppressor in a variety of malignancies, including GBM. However, its role in GBM is not fully understood. The mRNA or protein levels of targets in cells or tissues were determined by quantitative reverse transcription PCR (RT-qPCR) or Western blot, respectively. The GBM cell growth rate in vitro or in vivo was measured by Cell Counting Kit-8 or bioluminescence imaging, respectively. Upregulation of hsa-miR-338-3p and downregulation of phosphatidylinositol 3,4,5-trisphosphate-dependent Rac exchanger 2 protein (Prex2) were observed in GBM tissues compared to normal brain tissues. We further confirmed that murine Prex2 was a target of mmu-miR-338-3p in GBM. Mmu-miR-338-3p exerted profound inhibition effects on GBM cell growth in vitro or in vivo through targeting Prex2, leading to attenuation of (Protein kinase B) AKT/Signal transducer and activator of transcription 3 (STAT3) signaling activation. Restoration of mmu-miR-338-3p or inhibition of Prex2 may facilitate the development of innovative therapies for GBM treatment.

LncRNA NEAT1 promotes glioma cancer progression via regulation of miR-98-5p/BZW1.

BACKGROUND: Glioma is the most common malignant tumor in the human central nervous system. Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) promotes oncogenesis in various tumors. In the present study, we aimed to examine the role of NEAT1 in altering the properties of gliomas. METHODS: Quantitative real-time PCR technology was used to determine the expression levels of relevant genes in tumor tissues and cell lines. The protein expression levels were validated by Western blotting. Cell counting kit-8 (CCK-8) and colony formation assays were used to test the cell proliferation ability. A luciferase reporter assay was used to determine the interactions of the genes. Tumor xenografts were used to detect the role of NEAT1 in gliomas in vivo. RESULTS: We demonstrated that NEAT1 up-regulated glioma cells and negatively correlated with miR-98-5p in glioma tissues. A potential binding region between NEAT1 and miR-98-5p was confirmed by dual-luciferase assays. NEAT1 knockdown inhibited glioma cell proliferation. The inhibition of miR-98-5p rescued the knockdown of NEAT1 in glioma cells. Basic leucine zipper and W2 domain containing protein 1 (BZW1) was identified as a direct target of miR-98-5p. We also identified that BZW1 was positively correlated with NEAT1 in glioma tissues. NEAT1 knockdown inhibited glioma cell proliferation in vivo via miR-98-5p/BZW1. CONCLUSION: Our results suggest that NEAT1 plays an oncogenic function in glioma progression. Targeting NEAT1/miR-98-5p/BZW1 may be a novel therapeutic treatment approach for glioma patients.

Effectiveness of Superficial Temporal Artery-to-Middle Cerebral Artery Anastomosis in Treating Moyamoya Disease by Reducing Endothelial Progenitor Cells.

OBJECTIVE: To explore the effectiveness of superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis in treating moyamoya disease (MMD). METHODS: A total of 30 patients with MMD (hemorrhagic type, n = 13; ischemic type, n = 17) who had undergone STA-MCA anastomosis were enrolled in this study (anastomosis group). Cerebral blood flow was evaluated before and after surgery using cerebral angiography and computed tomography (CT) perfusion imaging. In addition, 27 patients with MMD (hemorrhagic type, n = 11; ischemic type, n = 16) who had received only conservative treatment were enrolled as the control group. Patients in both the anastomosis group and the control group were followed up for 5 years, and the incidences of cerebral hemorrhage and cerebral ischemia were analyzed. Blood samples were collected in both groups before and after treatment. Mononuclear cells were separated by density gradient centrifugation. After labeling with 3 direct fluorescent antibodies (CD133, CD34, and vascular endothelial growth factor receptor 2), the number of endothelial progenitor cells (EPCs) was detected using flow cytometry. RESULTS: Cerebral blood flow was remarkably improved after STA-MCA anastomosis. The incidences of cerebral hemorrhage and cerebral ischemia were significantly lower in the anastomosis group than in the control group. The number of EPCs showed no significant change before and after treatment in the control group; in contrast, it was decreased significantly after surgery in the anastomosis group. CONCLUSIONS: STA-MCA anastomosis can reduce the number of EPCs in MMD patients, lower the risk of rebreeding, and improve cerebral ischemic attacks.

[Preoperative location of major language functional cerebral areas using functional magnetic resonance imaging].

OBJECTIVE: To design a set of functional magnetic resonance imaging (fMRI) tasks to activate the major Chinese language functional areas. METHODS: Eight volunteers and 3 patients received fMRI studies with the tasks of semantic judgment, word reading and listening comprehension. Brain activation map of each task was obtained after standard fMRI data processing. RESULTS: The fMRI examination with 3 tasks activated middle frontal gyrus (BA 9), Broca area and Wernicke area respectively. CONCLUSION: A set of fMRI examinations, including semantic judgment, word reading and listening comprehension, can activate the major Chinese language functional areas steadily and may be used as a preoperative localizer of language areas.

[Melanocytic neoplasms of central nervous system analysis].

OBJECTIVE: To explore the clinical manifestations, diagnosis, treatment and prognostic features of melanocytic neoplasms of central nervous system (CNS). METHODS: A total of 24 patients with melanocytic neoplasms of CNS underwent surgery and were confirmed pathologically our hospital during 2006 - 2012. Their clinical data were collected. There were primitive melanocytic neoplasms (n = 8) and metastatic melanoma (n = 16) according to the diagnostic criteria of Willis. The scans of magnetic resonance imaging (MRI) showed hyper-intensity on T1 weighted image (n = 15) and hypo-intensity on T2 weighted image (n = 20). RESULTS: The outcomes were total resection (n = 11), subtotal resection (n = 9) and partial resection (n = 4). All 8 primitive melanocytic neoplasms were followed up. Among them, 2 cases died postoperatively at 15 and 40 months respectively. The remaining 6 cases survived 13 - 56 months after craniotomy. And 14/16 patients of metastatic melanoma were followed up, 8 cases died and the mean survival period was 4.5 months. The remaining 6 cases survived 1-7 months after craniotomy. Immunohistochemical staining demonstrated that the positive rate of HMB-45 was 9/10, S-100 9/11 and Vimentin 8/11. CONCLUSION: Melanocytic neoplasms of CNS are rare lesions with characteristic MRI features. Immunohistochemical staining helps to reach a definite pathological diagnosis. Surgical excision is recommended. Differentiation of primary and metastatic neoplasm is critical for prognostic evaluations.