Mitogen-activated protein kinases/Extracellular signal-regulated kinase (MAPK/ERK) pathway is essential for migration and invasion of malignant glioma. It is efficient to inhibit migration and invasion of glioma cells by targeting this pathway. Oleanolic acid (OA) has been well demonstrated to suppress survival, growth and angiogenesis of glioma cells. However, it is still unknown if OA affects the migration and invasion of glioma cells. We utilized U-87 MG glioma cell lines and primary glioma cells from patients to study the effect of OA on migration and invasion of glioma cells with multidisciplinary approaches. In this study, we found that OA significantly decreased the ability of glioma cells to migrate and invade. Epithelial-mesenchymal transition (EMT) of glioma cells was also suppressed by OA treatment. Furthermore, MAPK/ERK pathway was greatly inhibited in glioma cells under OA treatment. MAPK/ERK reactivation induced by a recombinant lentiviral vector, Lv-MEK, was able to rescue the inhibitory effect of OA on migration and invasion of glioma cells. Taken together, we provided evidences that OA was a MAPK/ERK pathway-targeting anti-tumor agent. Although the concentrations we used exceeded its physiological level, OA may be used to prevent migration and invasion of glioma cells by developing its derivatives with enhanced bioactivity.

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As an aggressive cancer with high morbidity, malignant glioma always has a poor prognosis even after surgery, chemotherapy and radiotherapy. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) shows a strong apoptosis-inducing effect on a variety of cancer cells including glioma. However so far, TRAIL delivery mediated by adenoviral vectors lacks tumor specificity and thus has cytotoxicity to normal cells. To improve the tumor-specificity of adenovirus-mediated TRAIL delivery, we utilized miR-124, miR-128, miR-146b and miR-218 to restrict its expression to within glioma cells. qPCR assay showed that expression of these four miRNAs was greatly downregulated in glioma in comparison with normal brain tissue. Luciferase reporter assay confirmed that miR-124, miR-128, miR-146b and miR-218 conferred exogenous gene expression with glioma-specificity. By inserting miRNA response elements (MREs) of these miRNAs into the downstream of TRAIL on adenoviral vectors, TRAIL was highly expressed in glioma cells, but not in normal brain cells. Cell viability and immunoblotting assays and FACS analysis showed that cytotoxicity and apoptosis elicited by TRAIL was only observed in glioma cells, rather than normal brain cells. Animal experiments also showed that MREs-regulated TRAIL delivery reduced the growth of glioma xenograft. In this study, we proved that miRNA-mediated tumor specific delivery of TRAIL was able to inhibit the survival of glioma cells and reduce the growth of glioma in vivo.

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Nano-sized hydroxyapatite (nHA) particles have been demonstrated to exert anti-cancer effects on multiple cancer cell lines and animal models of cancer biology. However, the molecular mechanism underlying the effects of nHA particles on glioma cells remains unclear. The present study aimed to examine the effects of nHA on the behavior of glioma cells and investigate its underlying molecular mechanism. Rat glioma C6 cells and human glioma U87MG ATCC cells were exposed to nHA (20–100 µg/ml), and its effects on cell morphology, viability, apoptosis, cell cycle, invasion and nuclear factor (NF)-κB signaling were analyzed. Exposure of C6 and U87MG ATCC cells to 20 µg/ml nHA for 24 h caused cell detachment. Viability of C6 and U87MG ATCC cells were significantly reduced by nHA in a dose-dependent manner (P<0.05). Nuclear staining with Hoechst 33258 exhibited clear chromatin condensation in C6 cells following 24 h exposure to ≥25 µg/ml nHA. Flow cytometry revealed that nHA (20–100 µg/ml) significantly induced apoptosis and cell cycle G2/M arrest in C6 and U87MG ATCC cells (P<0.05). Transwell invasion assay demonstrated that nHA (20–60 µg/ml) significantly inhibited invasion of U87MG ATCC cells (P<0.05). Furthermore, western blotting and confocal immunofluorescence microscopy revealed that nHA (20–100 µg/ml) decreased NF-κB p65 protein expression and blocked NF-κB p65 nuclear translocation in C6 cells. The protein expression of NF-κB target molecules, such as B cell lymphoma 2, cyclooxygenase-2 and survivin, were also significantly reduced by nHA in a dose-dependent manner in both C6 and U87MG ATCC cells (P<0.05). In conclusion, it was demonstrated that the inhibitory effect of nHA on glioma cells is likely associated with the downregulation of NF-κB signaling.

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Background: Some microRNAs have been found to be abnormal in patients with acute cerebral infarction (ACI) after intravenous thrombolysis. This study aimed to measure the expression of miR-106a-5p in ACI patients before and after thrombolytic treatment, and to investigate the prognostic value of miR-106a-5p and computed tomography perfusion imaging (CTPI) parameters in ACI patients receiving thrombolysis. Methods: The levels of serum miR-106a-5p were detected by quantitative real-time PCR in 78 ACI patients before thrombolysis, 24 hours after thrombolysis, and 3 months (90 days) after onset. The correlation of miR-106a-5p with continuous variables were analyzed using Pearson correlation analysis. The association of miR-106a-5p and CTPI parameters with prognosis of patients receiving thrombolysis was evaluated by logistic regression analysis. The accuracy and thresholds of miR-106a-5p and CTPI parameters for discriminating patients with unfavorable prognosis after thrombolysis were assessed by receiver operating characteristic analysis. Results: Serum miR-106a-5p expression was decreased in ACI patient after thrombolysis. Then, significant correlations of miR-106a-5p with National Institutes of Health Stroke Scale and CTPI parameters were found. Moreover, miR-106a-5p, cerebral blood flow (CBF) and cerebral blood volume (CBV), which are 2 CTPI parameters, were independently correlated with short- and long-term prognosis after thrombolysis. Furthermore, miR-106a-5p, CBF and CBV revealed good accuracy in predicting the prognosis of patients after thrombolysis, and their combination showed the best accuracy. Conclusion: Thrombolysis downregulates miR-106a-5p in ACI patients, and miR-106a-5p, CBF and CBV have considerable potentials to predict short- and long-term prognosis in ACI patients receiving intravenous thrombolysis.