TUSC3 suppresses glioblastoma development by inhibiting Akt signaling.

Glioblastoma multiform is one of the most common and most aggressive brain tumors in humans. The molecular and cellular mechanisms responsible for the onset and progression of GBM are elusive and controversial. The function of tumor suppressor candidate 3 (TUSC3) has not been previously characterized in GBM. TUSC3 was originally identified as part of an enzyme complex involved in N-glycosylation of proteins, but was recently implicated as a potential tumor suppressor gene in a variety of cancer types. In this study, we demonstrated that the expression levels of TUSC3 were downregulated in both GBM tissues and cells, and also found that overexpression of TUSC3 inhibits GBM cell proliferation and invasion. In addition, the effects of increased levels of methylation on the TUSC3 promoter were responsible for decreased expression of TUSC3 in GBM. Finally, we determined that TUSC3 regulates proliferation and invasion of GBM cells by inhibiting the activity of the Akt signaling pathway.

Simvastatin Inhibits Tumor Growth and Migration by Mediating Caspase-1-Dependent Pyroptosis in Glioblastoma Multiforme.

OBJECTIVES: Glioblastoma multiforme (GBM) is the most common and lethal central nervous system cancer and is associated with a poor prognosis. Simvastatin, a kind of widely used hypolipidemic agent, has been investigated for its beneficial effects on various types of cancers. The main purpose of this paper is to investigate the potential inhibitory effects of simvastatin on GBM and the underlying mechanism. METHODS: Cell viability and cell cycle of simvastatin-treated U87 and U251 cells were determined by CCK8 assay and flow cytometry, respectively. Additionally, we assessed cell migration and invasion abilities using a wound-healing assay and transwell assay. mRNA and protein expression patterns of caspase-1 and its markers nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3 (NLRP3) and IL-1ß in different conditions were detected by real-time polymerase chain reaction, immunofluorescence staining, and Western blot. RESULTS: Simvastatin decreased the viability of GBM cells and inhibited cell migration and invasion in a dose-dependent manner. Moreover, suppression of pyroptosis, as characterized by decreased expression of caspase-1, NLRP3, and IL-1ß, was observed. However, use of an miR-214 inhibitor reversed the simvastatin suppressive effect on GBM cells. CONCLUSIONS: Simvastatin inhibits GBM progression by suppressing caspase-1-dependent pyroptosis, regulated by miR-214.

Antitumor Effects of Berberine on Gliomas via Inactivation of Caspase-1-Mediated IL-1ß and IL-18 Release.

Gliomas arise in the glial cells of the brain or spine and are the most prevalent and devastating type of brain tumors. Studies of tumor immunology have established the importance of the tumor micro-environment as a driver of oncogenesis. Inflammatory mediators such as IL-1ß and IL-18 released by monocytes regulate transcriptional networks that are required for malignant cell growth. Berberine is a natural botanical alkaloid that is widely found in the Berberis species. Although it has been widely used as an anti-diarrheal treatment in North America for several decades, our study is the first to investigate berberine as an anti-tumor agent in glioma cells. In this study, we demonstrate that berberine significantly inhibits inflammatory cytokine Caspase-1 activation via ERK1/2 signaling and subsequent production of IL-1ß and IL-18 by glioma cells. Moreover, we found that berberine treatment led to decreased motility and subsequently cell death in U251 and U87 cells. In addition, our study is the first to indicate that berberine can reverse the process of epithelial-mesenchymal transition, a marker of tumor invasion. Taken together, our work supports berberine as a putative anti-tumor agent targeting glioma cells.

miRNA-214 Inhibits Cellular Proliferation and Migration in Glioma Cells Targeting Caspase 1 Involved in Pyroptosis.

Pyroptosis is a type of proinflammatory programmed cell death mediated by caspase 1 activity and occurs in several types of eukaryotic tumor cells, including gliomas. MicroRNAs (miRNAs), small endogenous noncoding RNAs, have been demonstrated to be advantageous in glioma therapy. However, the question of whether miRNAs regulate pyroptosis in glioma remains unknown. The current study found that caspase 1 expression was substantially increased in both glioma tissues and glioma cell lines, U87 and T98G, while miR-214 expression was significantly downregulated. Luciferase reporter assay recognized caspase 1 as a target gene of miR-214. These findings demonstrate that miR-214 could inhibit cell proliferation and migration through the regulation of pyroptosis intermediated by caspase 1 in glioma U87 and T98G cells and may suggest a novel therapeutic for the intervention of glioma.

Gene expression analysis reveals the dysregulation of immune and metabolic pathways in Alzheimer's disease.

In recent years, several pathway analyses of genome-wide association studies reported the involvement of metabolic and immune pathways in Alzheimer's disease (AD). Until now, the exact mechanisms of these pathways in AD are still unclear. Here, we conducted a pathway analysis of a whole genome AD case-control expression dataset (n=41, 25 AD cases and 16 controls) from the human temporal cortex tissue. Using the differently expressed AD genes, we identified significant KEGG pathways related to metabolism and immune processes. Using the up- and down- regulated AD gene list, we further found up-regulated AD gene were significantly enriched in immune and metabolic pathways. We further compare the immune and metabolic KEGG pathways from the expression dataset with those from previous GWAS datasets, and found that most of these pathways are shared in both GWAS and expression datasets.

The effect of simvastatin treatment on proliferation and differentiation of neural stem cells after traumatic brain injury.

OBJECTIVE: To study the effect of simvastatin on neurological functional recovery after traumatic brain injuries (TBI) and the possible molecular mechanisms, we evaluated simvastatin-induced proliferation and differentiation of neural stem cells (NSCs) in vitro and in vivo and possible involvement of Notch-1 signaling in this process. METHODS: Adult Wistar rats were randomly divided into three groups (n=28 for each): sham group, saline-treated group and simvastatin-treated group. Simvastatin was given orally at a dose of 1mg/kg/day starting at day 1 after TBI. At 1, 3, 7, 14, 21, 28, and 35 days after simvastatin treatment, functional outcome was measured using modified neurological severity scores (mNSS). Immunofluorescence of nestin was used to identify neurogenesis of NSCs in injured area of TBI rats. Western blot was applied to detect the expression level of Notch-1 protein in TBI rats with simvastatin. RESULTS: Immunostaining showed a significant increase in the number of nestin-positive cells in injured area of the simvastatin-treated group compared to that of the saline-treated group (p<0.05). In in vitro experiment, simvastatin induced enhanced proliferation and neurogenesis of cultured NSCs and elevated Notch-1 protein expression. Co-incubation of γ-secretase inhibitor, an inhibitor of Notch-1 pathway, with simvastatin abolished its neurorestoration effect. Most importantly, the simvastatin-treated group had significantly decreased mNSS at day 35 after TBI compared with the saline-treated group (p<0.05). CONCLUSION: Simvastatin treatment enhanced neurological functional recovery after TBI possibly via activation of Notch signaling and increasing neurogenesis in the injured area.

Long-term seizure outcome for international consensus classification of hippocampal sclerosis: a survival analysis.

PURPOSE: Surgery is regarded as a common treatment option for patients with mesial temporal lobe epilepsy (MTLE) as a result of hippocampal sclerosis (HS). However, approximately one-third of patients with intractable epilepsy did not become seizure-free after tailored resection strategies. It would be compelling to identify predictive factors of postoperative seizure outcomes. Our aim was to assess the correlation between HS classification and long-term postoperative seizure outcome in patients with MTLE due to HS. METHODS: To investigate HS classification, semi-quantitative analysis and immunohistochemical staining of neuronal nuclei (NeuN) were performed on 100 postoperative hippocampal specimens. All patients had a 1-7 year postoperative follow-up. The postoperative seizure outcome was evaluated using International League Against Epilepsy (ILAE) outcome classification. RESULTS: Three types of HS were recognized. The highest incidence of initial precipitating injury (IPI) was noted in the HS ILAE type 1 group (53.1%). The most favorable long-term seizure outcome was also noted in the HS ILAE type 1 group. The shortest epilepsy duration was recorded in the HS ILAE type 2 group (mean epilepsy duration=6.64 ± 5.83 years). The completely seizure free rate of patients in all groups declined with an increase in time. CONCLUSIONS: Our study for the first time demonstrated a significant correlation between HS ILAE types and long-term postoperative seizure outcome in patients with MTLE due to HS. Therefore, HS ILAE types have predictive value in long-term seizure outcome following epilepsy surgery.

miR-603 promotes glioma cell growth via Wnt/ß-catenin pathway by inhibiting WIF1 and CTNNBIP1.

Gliomas are the most common and deadly type of brain tumor. In spite of progressive treatments, patient prognosis has not improved significantly. MicroRNAs are considered promising candidates for glioma therapy. MiR-603 was found overexpressed in both glioma tissues and cell lines. MiR-603 promoted cell proliferation, cell cycle progression and neurosphere formation. Conversely, inhibition of miR-603 remarkably reduced these effects. We confirmed that WIF1 and CTNNBIP1 are bona fide targets of miR-603. The negative correlation between miR-603 and these molecules' expression was shown by Pearson correlation in 50 primary glioma tissue samples. Furthermore, overexpression of miR-603 promoted nuclear ß-catenin levels and TOPflash luciferase activity, indicating that miR-603 activates the Wnt/ß-catenin signaling pathway. Our in vivo results confirmed the positive role of miR-603 in glioma development. We demonstrate that miR-603 regulates glioma development via its WIF1 and CTNNBIP1 targets, which suggests that miR-603 may be a promising candidate for therapeutic applications in glioma treatment.

Long-term outcome of epilepsy surgery: a retrospective study in a population of 379 cases.

We evaluated the long-term outcome of epilepsy surgery in drug-resistant epilepsy patients, and investigated preoperative factors associated with postoperative long-term surgical outcome. We performed a retrospective study of 379 patients who received epilepsy surgeries from 2000 to 2010. Patients had completed a minimum of 2-year and up to 12-year follow-up. Preoperative evaluations, surgical outcomes and clinical data of patients were collected and analyzed. We found that the epilepsy surgery was effective in drug-resistant patients and the long-term outcome of epilepsy surgery was satisfactory. The bipolar electro-coagulation could improve the surgical outcome when the epileptogenic focus was on the functional cortex. Results of the 2-year follow-up showed that preoperative seizure characteristics including the history of febrile seizure, seizure frequency, and location, quantity and range of seizure foci were significantly associated with the surgical outcome. The surgery procedure including the surgery type and the extent of resection also affected outcome. Abnormal head or hippocampus MRI, inconsistent results of preoperative investigations, seizure types, and pathology type might also be predictors of long-term surgical outcome.

The effects of simvastatin on hippocampal caspase-3 and Bcl-2 expression following kainate-induced seizures in rats.

Status epilepticus (SE) causes neuronal loss and apoptosis by inducing several apoptosis-regulatory genes. Two such genes, cysteinyl aspartate-specific protease-3 (caspase-3), an apoptosis activator, and B-cell leukemia-2 (Bcl-2), an apoptosis suppressor, are tightly regulated for their expression and activation. Statins, inhibitors of HMG-CoA reductase, have been recently recognized as neuroprotective drugs. However, their underlying mechanisms are still unclear. In this study, we examined the neuroprotective effects of simvastatin in a rat model of SE induced by kainic acid (KA). Feeding of simvastatin for 3 days after kainate injection rescued SE-induced neuronal apoptosis, as determined by histological examination of brain sections at the level of the dorsal hippocampus. Semi-quantitative RT-PCR showed that SE treatment markedly increased caspase-3 mRNA expression and reduced Bcl-2 mRNA expression in the hippocampus. Similarly, western blot analysis and immunohistochemical analysis of the rat hippocampus demonstrated that under SE treatment, caspase-3 protein levels significantly increased and peaked at 72 h, whereas Bcl-2 protein levels decreased from 6-24 h following SE. Interestingly, simvastatin could reverse the aforementioned SE-induced changes, suggesting that the neuroprotective effects of simvastatin against neuronal apoptosis may be achieved by inhibiting caspase-3 expression and increasing Bcl-2 expression.

Administration of simvastatin after kainic acid-induced status epilepticus restrains chronic temporal lobe epilepsy.

In this study, we examined the effect of chronic administration of simvastatin immediately after status epilepticus (SE) on rat brain with temporal lobe epilepsy (TLE). First, we evaluated cytokines expression at 3 days post KA-lesion in hippocampus and found that simvastatin-treatment suppressed lesion-induced expression of interleukin (IL)-1ß and tumor necrosis factor-α (TNF-α). Further, we quantified reactive astrocytosis using glial fibrillary acidic protein (GFAP) staining and neuron loss using Nissl staining in hippocampus at 4-6 months after KA-lesion. We found that simvastatin suppressed reactive astrocytosis demonstrated by a significant decrease in GFAP-positive cells, and attenuated loss of pyramidal neurons in CA3 and interneurons in dentate hilar (DH). We next assessed aberrant mossy fiber sprouting (MFS) that is known to contribute to recurrence of spontaneous seizure in epileptic brain. In contrast to the robust MFS observed in saline-treated animals, the extent of MFS was restrained by simvastatin in epileptic rats. Attenuated MFS was related to decreased neuronal loss in CA3 and DH, which is possibly a mechanism underlying decreased hippocampal susceptibility in animal treated with simvastatin. Electronic encephalography (EEG) was recorded during 4 to 6 months after KA-lesion. The frequency of abnormal spikes in rats with simvastatin-treatment decreased significantly compared to the saline group. In summary, simvastatin treatment suppressed cytokines expression and reactive astrocytosis and decreased the frequency of discharges of epileptic brain, which might be due to the inhibition of MFS in DH. Our study suggests that simvastatin administration might be a possible intervention and promising strategy for preventing SE exacerbating to chronic epilepsy.