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Although the World Health Organization (WHO) histological criteria distinguishing benign from atypical and malignant meningioma are clear, discerning benign from atypical meningioma is still somewhat difficult, leading to interobserver diagnostic variability. Osteopontin (OPN) and cortactin play important roles in tumorigenesis, invasion and metastasis of several human cancers. The aim of this study was to evaluate the usefulness of OPN and cortactin immunohistochemistry for distinguishing between benign, atypical and malignant meningioma and predicting their recurrence.Seventy-five specimens (48 benign, 17 atypical and 10 malignant meningiomas) were investigated immunohistochemically. The mean immunohistochemical scoreimmunohistochemical score ± SE of the mean of both OPN and cortactin were significantly higher in grade II or grade III meningiomas than in grade I meningioma. Discriminant analysis of immunohistochemical OPN expression showed correct classification of 97.7% of WHO grade I meningiomas and 88.2% of WHO grade II meningiomas (95.4% accuracy). However, the same analysis of cortactin expression showed correct classification of 95.8% of WHO grade I meningiomas and only 23.5% of WHO grade II meningiomas (76.9% accuracy). A cut-off for predicting grades I and II meningioma recurrence was determined for OPN (3.0) but not for cortactin. Finally, logistic regression identified both this cut-off (P0.05) and WHO grade (P0.05) as independent risk factors for recurrence.OPN expression is a valuable marker for diagnosis of atypical meningioma and prediction of grades I and II meningioma recurrence.

Mesenchymal stromal/stem cells (MSCs) are widely distributed in different tissues such as bone marrow, adipose tissues, peripheral blood, umbilical cord and amnionic fluid. Recently, MSC-like cells were also found to exist in rat olfactory bulb and are capable of inducing differentiation into mesenchymal lineages - osteocytes, chondrocytes and adipocytes. However, whether these cells can differentiate into myocardial cells is not known. In this study, we examined whether olfactory bulb-derived MSCs could differentiate into myocardial cells in vitro. Fibroblast-like cells isolated from the olfactory bulb of neonatal rats were grown under four conditions: no treatment; in the presence of growth factors (neuregulin-1, bFGF and forskolin); co-cultured with cardiomyocytes; and co-cultured with cardiomyocytes plus neuregulin-1, bFGF and forskolin. Cell differentiation into myocardial cells was monitored by RT-PCR, light microscopy immunofluorescence, western blot analysis and contractile response to pharmacological treatments. The isolated olfactory bulb-derived fibroblast-like cells expressed CD29, CD44, CD90, CD105, CD166 but not CD34 and CD45, consistent with the characteristics of MSCs. Long cylindical cells that spontaneously contracted were only observed following 7 days of co-culture of MSCs with rat cardiomyocytes plus neuregulin-1, bFGF and forskolin. RT-PCR and western blot analysis indicated that the cylindrical cells expressed myocardial markers, such as Nkx2.5, GATA4, sarcomeric α-actinin, cardiac troponin I, cardiac myosin heavy chain, atrial natriuretic peptide and connexin 43. They also contained sarcomeres and gap junction and were sensitive to pharmacological treatments (adrenal and cholinergic agonists and antagonists). These findings indicate that rat olfactory bulb-derived fibroblast-like cells with MSC characteristics can differentiate into myocardial-like cells.

Autoimmune diabetes results from a progressive destruction of insulin-producing beta cells in the pancreatic islets by chemokine-attracted lymphocytes. Because islet cells in NOD mice produce chemokines during the development of autoimmune diabetes, we investigated the role of inflammatory CC chemokines in disease progression in these mice.We generated a transgenic NOD mouse model that overproduces the inflammatory CC chemokine decoy receptor D6 in pancreatic islets.The frequency of diabetes and insulitis scores of transgenic mice were decreased significantly, compared with non-transgenic control littermates. Transgenic expression of D6 (also known as Ccbp2) did not affect systemic lymphocyte development or alter: (1) the T cell subsets such as T helper (Th)1, Th2 and T regulatory cells; or (2) antigen-presenting cells such as dendritic cells or macrophages. The percentages and numbers of T and B lymphocytes were decreased significantly in the pancreas. Activation status, autoantigen-specific proliferation and diabetogenicity of lymphocytes were also markedly reduced.Inflammatory CC chemokines play a critical role in the development of autoimmune diabetes. Transgenic expression of D6 in pancreatic islets of NOD mice reduced this pathogenic process by suppressing activation of autoreactive lymphocytes and by reducing migration of lymphocytes to the pancreas.

Object Glioblastoma, the most common primary brain tumor, has a poor prognosis, even with aggressive resection and chemoradiotherapy. Recent studies indicate that CD133+ cells play a key role in radioresistance and recurrence of glioblastoma. Cyclooxygenase-2 (COX-2), which converts arachidonic acid to prostaglandins, is over-expressed in a variety of tumors, including CD133+ glioblastomas. The COX-2–derived prostaglandins promote neovascularization during tumor development, and conventional radiotherapy increases the proportion of CD133+ cells rather than eradicating them. The aim of the present study was to investigate the role of celecoxib, a selective COX-2 inhibitor, in enhancing the therapeutic effects of radiation on CD133+ glioblastomas. Methods Cells positive for CD133 were isolated from glioblastoma specimens and characterized by flow cytometry, then treated with celecoxib and/or ionizing radiation (IR). Clonogenic assay, cell irradiation, cell cycle analysis, Western blot, and xenotransplantation were used to assess the effects of celecoxib alone, IR alone, and IR with celecoxib on CD133+ and CD133− glioblastoma cells. Three separate xenotransplantation experiments were carried out using 310 severe combined immunodeficient (SCID) mice: 1) an initial tumorigenicity evaluation in which 3 different quantities of untreated CD133– cells or untreated or pretreated CD133+ cells (5 treatment conditions) from 7 different tumors were injected into the striatum of 2 mice (210 mice total); 2) a tumor growth study (50 mice); and 3) a survival study (50 mice). For these last 2 studies the same 5 categories of cells were used as in the tumorigenicity (untreated CD133– cells, untreated or pretreated CD133+ cells, with pretreatment consisting of celecoxib alone, IR alone, or IR and celecoxib), but only 1 cell source (Case 2) and quantity (5 × 104 cells) were used. Results High levels of COX-2 protein were detected in the CD133+ but not the CD133− glioblastoma cells. The authors further demonstrated that 30 μM celecoxib was able to effectively enhance the IR effect in inhibiting colony formation and increasing IR-mediated apoptosis in celecoxib-treated CD133+ glioblastoma cells. Furthermore, reduction in radioresistance was correlated with the induction of G2/M arrest, which was partially mediated through the increase in the level of phosphorylated-cdc2. In vivo xenotransplant analysis further confirmed that CD133+-associated tumorigenicity was significantly suppressed by celecoxib treatment. Importantly, pretreatment of CD133+ glioblastoma cells with a combination of celecoxib and IR before injection into the striatum of SCID mice resulted in a statistically significant reduction in tumor growth and a statistically significant increase in the mean survival rate of the mice. Conclusions Celecoxib combined with radiation plays a critical role in the suppression of growth of CD133+ glioblastoma stemlike cells. Celecoxib is therefore a radiosensitizing drug for clinical application in glioblastoma.

Recent advances in research have found that tumor stem-like cells are resistant to surgery, radiotherapy, and chemotherapy. Tumor stem-like cells play critical roles in tumor recurrence, angiogenesis, and invasion in malignant brain tumors. However, the identification of tumor stem-like cells in meningiomas has not been clarified. In this study, we identified the stem-like features of sphere-forming cells in human meningiomas. The results showed that meningioma stem-like cells possess the ability to form spheres in identical stem cell culture condition. These meningioma sphere cells (MgSCs) expressed progenitor cell marker, CD133, but not differentiated cell marker, epithelial membrane antigen (EMA) on immunofluorescence staining. Importantly, the mRNA expression of ABCG, and CD133 was higher in MgSCs than daughter meningioma adherent cells (MgACs). In addition, cells displayed chemotherapeutic resistance to vincristine more in MgSCs than MgACs. This phenomenon was also found in single cell form from dissociated spheres than MgACs. Moreover, MgSCs are more resistant to irradiation treatment than MgACs. Furthermore, MgSCs revealed high tumorigenicity in vivo following orthotopic inoculation into the brains of immunodeficient mice. The corresponding immunohistochemical (IHC) staining found that MgSCs are positive for EMA, vimentin, and CD133, consistent with IHC of primary human meningiomas. These findings have provided better understanding of meningioma cell biology and suggested that meningioma stem-like cells may serve as a novel target in therapeutic resistant meningiomas.

Angiogenesis is the hallmark of malignant gliomas positively correlated with the vascular endothelial growth factor (VEGF) expression. We previously reported that expression levels of Nodal, a member of transforming growth factor-β super family, correlate with the malignant invasive behavior of human glioma cells. In this study, we show that knockdown of Nodal suppresses glioma angiogenesis by inhibition of VEGF. In human primary glioma specimens, expression of Nodal positively correlates with WHO glioma tumor grades and expression of VEGF in the corresponding glioma specimens. In human U87MG glioma cells, knockdown of endogenous Nodal by RNA interference (RNAi) significantly decreases colony formation and secretion of VEGF. In vivo, cellular depletion of Nodal in U87MG inhibited brain glioma growth and prolonged the survival of mice with U87MG/shNodal glioma compared with controls. Inhibition of Nodal suppressed tumor vessel growth in U87MG gliomas. Using Nodal inhibitor (SB431542), silencing Nodal, or overexpressing Nodal in the U87MG, GBM8401, and GBM glioma cells, our further experiments revealed that Nodal-induced VEGF expression might, at least in part, mediate through the ERK1/2-HIF-1α-mediated signaling pathway. Taken together, our data revealed that alteration of Nodal expression in glioma cells resulted in changes to VEGF secretion, and subsequent colony formation, in vivo tumor growth, and angiogenesis, all of which are consistent with the regulation of VEGF through the ERK1/2-HIF-1α-mediated signaling, suggesting that Nodal may serve as a potential therapeutic target for the treatment of human gliomas.

Uncontrolled growth and diffused invasion are major causes of mortality in patients with malignant gliomas. Nodal has been shown to have a central role in the tumorigenic signaling pathways of malignant melanoma. In this study, we show that grade IV human glioma cell lines expressed different levels of Nodal, paralleled to the potential for cell invasiveness. Treatment of glioma cell lines with recombinant Nodal (rNodal) increased matrix metalloproteinase 2 (MMP-2) secretion and cell invasiveness. The ectopic expression of Nodal in GBM glioma cells that expressed Nodal at low level resulted in increased MMP-2 secretion, enhanced cell invasiveness, raised cell proliferation rates in vitro, increased tumor growth in vivo, and was associated with poor survival in a mice xenograft model. In contrast, the knockdown of Nodal expression in U87MG glioma cells with high Nodal expression level had reduced MMP-2 secretion, less cell invasiveness, lower tumor growth in vivo and longer lifespan in mice with U87MG/shNodal cell xenografts. In addition, Nodal knockdown promoted the reversion of malignant glioma cells toward a differentiated astrocytic phenotype. Furthermore, our data support the notion that Nodal may regulate glioma progression through the induction of the leukemia inhibitory factor (LIF) and Cripto-1 through activated Smad.

Triptolide, a diterpenoid triepoxide derived from the Chinese herb Tripterygium wilfordii, exerts an antitumor effect in KB cancer cells through the induction of apoptosis. In this study, we show that triptolide possesses an anticancer effect on drug-sensitive parental KB cells and multidrug-resistant KB-7D and KB-tax cells that overexpress multidrug resistance protein and MDR, respectively. Our data revealed that triptolide decreases the expression of multidrug resistance protein and MDR in both KB-7D and KB-tax cells. It also induces apoptosis in these multidrug-resistant cancer cells by activating caspase-3, and decreasing Mcl-1 and XIAP. Triptolide not only inhibits tumor growth but also induces apoptosis of these drug-resistant cancer cells in xenograft mouse models. Moreover, we also show that triptolide combined with 5-fluorouracil could be an alternative strategy for chemotherapy enhancement. These results indicate the therapeutic value of triptolide on multidrug-resistant cells, and when combined with 5-fluorouracil for the enhancement of cancer therapy.

Islet transplantation has been established as a potential therapy for type 1 diabetes. However, inflammation, allorejection, and on-going autoimmune damage contribute to early graft loss and failure of islet transplantation. Melatonin is the major secretory product of the pineal gland during the dark period of each day and displays multifunctional properties including the regulation of circadian and seasonal rhythms, antioxidation reactions and immune modulation. Based on the immunosuppressive properties of melatonin, we investigated whether melatonin treatment prolonged the survival of islet grafts in non-obese diabetic (NOD) mice. The mean islet graft survival time was 7.33 ± 1.51 and 7.75 ± 2.66 days in untreated controls and in the solvent-treated animals, respectively. Strikingly, the mean survival time of islet grafts in recipients treated with melatonin (200 mg/kg/bw) was 17 ± 7.76 days. Moreover, melatonin treatment reduced the proliferation of splenocytes in NOD mice. Using a T1 and T2 double transgenic mouse model, we found that T helper 1 (Th1) cells in mice treated with melatonin were significantly decreased. The reduction of Th1 cells and T cell proliferation may result from an increase in the immunosuppressive cytokine IL-10. Our results indicate that melatonin treatment suppresses autoimmune recurrence by inhibiting the proliferation of Th1 cells in NOD mice and thus prolongs the survival of syngeneic islet grafts.

Stereotactic radiosurgery plays an important role in management of metastatic brain tumors, especially when the tumor has recurred after treatment with previous whole brain radiotherapy. Most metastatic brain tumors less than 1 cm 3 show a complete response after stereotactic radio-surgery. However, there are few reports of a dramatic change in the complete response of large metastatic brain tumors. Here, we report a case of adenocarcinoma of lung that had metastasized to the brain. Because the recurrence of the metastatic brain tumor measured approximately 3 cm in diameter, the tumor was previously treated with two prior craniotomies followed by whole brain radiation to the resection cavity. The tumor subsequently recurred and was treated with stereotactic radiosurgery (CyberKnife). A dramatic response was noted 3 months after radiosurgery with complete disappearance of the recurrent tumor.

Purpose To investigate the performance of hematoma shape, hematoma size, Glasgow coma scale (GCS) score, and intracerebral hematoma (ICH) score in predicting the 30-day mortality for ICH patients. To examine the influence of the estimation error of hematoma size on the prediction of 30-day mortality. Materials and Methods This retrospective study, approved by a local institutional review board with written informed consent waived, recruited 106 patients diagnosed as ICH by non-enhanced computed tomography study. The hemorrhagic shape, hematoma size measured by computer-assisted volumetric analysis (CAVA) and estimated by ABC/2 formula, ICH score and GCS score was examined. The predicting performance of 30-day mortality of the aforementioned variables was evaluated. Statistical analysis was performed using Kolmogorov-Smirnov tests, paired t test, nonparametric test, linear regression analysis, and binary logistic regression. The receiver operating characteristics curves were plotted and areas under curve (AUC) were calculated for 30-day mortality. A P value less than 0.05 was considered as statistically significant. Results The overall 30-day mortality rate was 15.1% of ICH patients. The hematoma shape, hematoma size, ICH score, and GCS score all significantly predict the 30-day mortality for ICH patients, with an AUC of 0.692 (P = 0.0018), 0.715 (P = 0.0008) (by ABC/2) to 0.738 (P = 0.0002) (by CAVA), 0.877 (P