幕上星形细胞瘤的凋亡及相关基因p53、bcl—2的表达

目的 探讨幕上星形细胞瘤的细胞凋亡以及p53、bcl-2在凋亡中的意义。方法 免疫组化TUNEL法检测细胞凋亡,SP法检测p53、bcl-2,实验数据由SPSS软件包分析处理。结果 细胞凋亡指数（AI）随着肿瘤级别的增高而增加,各级别肿瘤间AI的差异均有显著性意义（P＜0．01）;死亡组与存活组的AI的差异有显著性意义（P＜0．01）,AI＞0．5％组与AI＜0．5％组的术后1年生存率的差异有显著性意义（P＜0．05）;AI／MI（分裂指数）在高、低级别的星形细胞瘤中的差异有显著性意义（P＜0．05）。p53阳性组与p53阴性组的AI、MI术后1年生存率的差异均有显著性意义（均P＜0．05）。bcl-2阳性组与阴性组的AI、MI、预后均无统计学意义（均P＞0．05）。多因素logistic回归分析年龄分组、AI、AI／MI、放疗均与预后优劣相关。结论 AI可以作为提示预后的指标,并对判断幕上星形细胞瘤的生物学行为及肿瘤分级有指导意义;AI／MI值越小,肿瘤的恶性转化能力越强,预后越差;p53过度表达提示肿瘤恶性程度高、预后差;AI＜0．5％、AI／MI值大的、年龄较轻的、术后放疗病人预后较好。     

Differential expression of sst1, sst2A, and sst3 somatostatin receptor proteins in low-grade and high-grade astrocytomas

We have previously reported that sst2A somatostatin receptors are frequently overexpressed in human meningiomas. Initial clinical observations suggest that somatostatin analogues may also be of value for imaging and treatment of other human intracranial tumors, including astrocytomas. However, contradictory results have been reported regarding the expression of somatostatin receptors in low-grade and high-grade astrocytomas. Therefore, we determined the precise pattern of somatostatin receptor protein expression in 8 diffuse astrocytoma (DA), 10 anaplastic astrocytomas (AA), and 32 glioblastoma multiforme (GBM) using immunohistochemistry and Western blot analysis. sst1 and sst2A somatostatin receptors were not present in DA and only occasionally detected in AA. In GBM, sst1 was present in 66%, and sst2A was found in 44% of the tumors. sst3 receptors were present in 38% of DA, 40% of AA, and 84% of GBM. Thus, loss of differentiation was significantly associated with increased expression of sst1, sst2A, and sst3 somatostatin receptors. In contrast, sst4 and sst5 receptors were found in 80% and 25% of all cases, respectively, in a manner independent of histological grade. No significant correlation was found between somatostatin receptor expression and the proliferation rate of the tumors as determined by MIB-I immunostaining. Furthermore, the presence or absence of the 5 somatostatin receptor subtypes did not significantly influence survival time in 14 GBM patients.     

Preirradiation ifosfamide,carboplatin, and etoposide (ICE) for the treatment of high-grade astrocytomas in children

Background Astrocytomas are the most common form of primary intracranial tumor; however, survival of patients with high-grade tumors has not changed much compared with that reported in the early 1970s.Objective Our objective was to assess the efficacy, security, and survival rate of postoperative chemotherapy with ifosfamide, carboplatin, and etoposide (ICE) in pediatric patients with anaplastic astrocytomas (AA) and glioblastoma multiforme (GM).Methods In a phase II study, we evaluated 25 children with AA or GM. The proposed treatment was four courses of chemotherapy with ICE followed by hyperfractionated radiotherapy, and then four more courses of ICE. Patients were evaluated using MRI after surgery, after the second course of chemotherapy, and again after the last. Toxicity was determined before each course.Results The overall and disease-free survival at 60 months was 67% and 56% respectively. For supratentorial localization it was 92% at 60 months and 20% at 18 months for brain stem tumors. Fourteen patients had a complete response and 9 died as a result of tumor progression.Conclusions Postoperative chemotherapy with ICE reduces the tumor size and increases the survival rate of pediatric patients with malignant astrocytomas with minimal toxicity.A commentary on this paper is available at     

Interleukin-1α (IL-1α), IL-1β, IL-1 receptor type I, IL-1 receptor antagonist, and TGF-β1 mRNAs in pediatric astrocytomas, ependymomas, and primitive neuroectodermal tumors

Interleukin-1α (IL-1α), IL-1β, interleukin-1 receptor type I (IL-1RI, signaling receptor), and IL-1 receptor antagonist (IL-1Ra, endogenous inhibitor) are pivotal components of the IL-1 system. IL-1 and other cytokines induced by IL-1, such as TGF-β1, may participate in the growth of various tumor cells. In children, primary nervous system tumors represent the most common solid malignancy. We investigated the levels of IL-1α, IL-1β, IL-1RI, IL-1Ra, and TGF-β1 mRNAs in pediatric astrocytomas (n=19), ependymomas (n=13), and primitive neuroectodermal tumors (n=22) using sensitive and specific RNase protection assays. The data show a significant distinct cytokine mRNA profile among brain tumor types. Pilocytic, nonpilocytic, and anaplastic astrocytomas have significant increased levels of IL-1β, IL-1RI, and TGF-β1 mRNAs, but low levels of IL-1Ra mRNA; this may have implications for an IL-1β feedback system and IL-1β?TGF-β1 interactions in astrocytomas. Ependymomas show increased levels of IL-1α and IL-1β mRNAs associated with low levels of IL-1Ra mRNA; primitive neuroectodermal tumors do not exhibit increased levels of any cytokine component examined. The data also suggest that a dysregulation of the balance between stimulatory and inhibitory cytokines may be involved in the growth and development of brain tumors via autocrine/paracrine mechanisms.     

MMP-2, -3 and -9 levels and activity are not related to Abeta load in the frontal cortex in Alzheimer's disease

Matrix metalloproteinases (MMPs) -2, -3 and -9 are up-regulated in several cell types on exposure to amyloid β peptide (Aβ) and have Aβ-degrading activity in vitro . The aims of this study were to determine (i) the distribution of MMP-2, -3 and -9 in the cerebral cortex in Alzheimer's disease (AD) and control brains; (ii) whether the levels and activity of these proteases are increased in AD; and (iii) whether their activity is related to Aβ load. In addition, we examined whether promoter polymorphisms in the MMP-3 and -9 genes are associated with AD in the study cohort. Paraffin sections of frontal lobe from AD and control cases were immunostained for MMP-2, -3 and -9 and tissue homogenates used for MMP activity assays. DNA from these cases was genotyped for the MMP-3 5A/6A (-1171) and MMP-9 C-1562T promoter polymorphisms. Immunohistochemistry revealed MMP-3 in plaques and both MMP-3 and -9 around scattered neurones. The levels and activity of all three MMPs were similar in AD and control brains and bore no relationship to Aβ load. Analysis of MMP-3 -1171 5A/6A allele frequencies showed that the 6A allele (with reduced promoter activity) was associated with AD; the MMP-9 C-1562T polymorphism was not. The levels and activities of MMP-2, -3 and -9 are not increased in the frontal cortex in AD and are not related to Aβ load. Our findings suggest that altered expression of these proteases does not make a significant contribution to the accumulation of Aβ in AD.     

GFRα-3, a protein related to GFRα-1, is expressed in developing peripheral neurons and ensheathing cells

We report here the identification of a gene, termed GFRα-3 (glial cell line-derived neurotrophic factor family receptor alpha-3), related to GFRα-1 and GFRα-2 (also known as GDNFR-α and GDNFR-β), and describe distribution of GDNFα-3 in the nervous system and other parts of the mouse body during development and in the adult. GFRα-3 in situ hybridization signals were found mainly in the peripheral nervous system, with prominent signals in developing dorsal root and trigeminal ganglia. Sympathetic ganglia were also positive. Developing nerves manifested strong GFRα-3 mRNA signals, presumably generated by the Schwann cells. Olfactory ensheathing cells were also positive. Other non-neuronal cells appearing positive during development included chromaffin cells in the adrenal gland and small clusters of cells in the intestinal epithelium. In the central nervous system no robust signals could be detected at any stage investigated with the present probes. Compared with the previously described GFRα-1 and GFRα-2 mRNAs, which are widely distributed in the central nervous system and peripheral organs, the expression of GFRα-3 mRNA is much more restricted. The prominent expression in Schwann cells during development suggests a key role for GFRα-3 in the development of the peripheral nervous system. As Schwann cells are known to lack expression of the transducing RET receptor, we propose that a possible function of GFRα-3 during development could be to bind Schwann cell-derived GDNF-like ligands, thus presenting such molecules to growing axons.     

Alterations of hHrd1 expression are related to hyperphosphorylated tau in the hippocampus in Alzheimer's disease

The degradation of aberrantly phosphorylated tau in neurons plays an important role in the pathogenesis of Alzheimer's disease (AD). hHrd1 is a newly identified ubiquitin ligase involved in the endoplasmic reticulum (ER)-associated protein degradation. The expression and function of hHrd1 in AD brain remains elusive. In the present study, the expression of hHrd1 in AD hippocampus and the morphological relations between hHrd1 expression and pretangle formation were studied by using immunohistochemical single- and double-labeling methods. The results showed that hHrd1 was expressed in neurons and reactive astrocytes, especially in the CA2-CA4 hippocampal subfields. The ratio of hHrd1-positive neurons/astrocytes to total neurons/astrocytes was increased in the CA1 subfield in AD hippocampus compared with the age-matched controls (P < 0.05). Most Alz-50 labeled pretangles were colocalized with hHrd1, and the expression levels showed an inversed change, implied that hHrd1 might be associated with the degradation of hyperphosphorylated tau.     

Circulating levels of MMP-1, -2, -3, -9, and TIMP-1 are increased in POEMS syndrome

The authors quantitatively measured levels of matrix metalloproteinases (MMP), tissue inhibitor of metalloproteinases (TIMP), and vascular endothelial growth factor (VEGF) in blood samples of POEMS syndrome. Circulating levels of MMP-1, -2, -3, -9, and TIMP-1 were more increased in patients with POEMS syndrome than in patients with other neurologic disorders or in healthy controls. Serum levels of VEGF and TIMP-1 were strongly correlated with each other. Increased circulating levels of MMP-1, -2, -3, -9, and TIMP-1 may lead to a better understanding the pathogenesis of POEMS syndrome.     

14-3-3 Proteins,particularly of the epsilon isoform,are detectable in cerebrospinal fluids of cerebellar diseases in children

Background: Detection of 14-3-3 proteins in cerebrospinal fluid (CSF) is a powerful tool for elucidating the mechanisms of neurological disorders. There have been useful studies on 14-3-3 CSF protein detection in Creutzfeldt–Jakob disease and other neurological disorders, but none on cerebellar diseases. Objective: To elucidate whether 14-3-3 CSF proteins are a sensitive biomarker of cerebellar disruption in children. Materials and Methods: We examined 14-3-3 CSF proteins by immunoblotting in seven patients with cerebellar disorders: two with acute cerebellitis, two with acute cerebellar ataxia, and three with cerebellar atrophy. We also investigated 14-3-3 CSF proteins in four cases of febrile seizure and three of influenza-related encephalopathy. Isoforms of 14-3-3 proteins were also identified using isoform-specific antibodies. Results: 14-3-3 proteins were detected in CSF of six patients with cerebellar disorders, the exception being one with acute cerebellar ataxia caused by viral infection. Interestingly, only the 14-3-3 ε isoform was detected in two tested patients with cerebellar involvement. Moreover, longitudinal analysis of 14-3-3 CSF proteins in one patient with infantile neuroaxonal dystrophy showed that the 14-3-3 band density proportionally decreased when the cerebellar atrophy gradually progressed. Another CSF derived from a case of febrile seizure showed no 14-3-3 proteins, whereas all those derived from influenza-related encephalopathy demonstrated 14-3-3 CSF proteins with six isoforms. Conclusions: This is the first report on 14-3-3 CSF proteins as a significant biomarker of cerebellar disruption, as well as other brain diseases. Since 14-3-3 ε is localized in the molecular layer of cerebellum, the unique detection of 14-3-3 ε may indicate cerebellar involvement in the brain.     

GAT1 and GAT3 expression are differently localized in the human epileptogenic hippocampus

The gamma amino butyric acid (GABA) transporters GAT-1 and GAT-3 were localized by immunohistochemistry in hippocampi removed for the control of medically intractable temporal lobe epilepsy (TLE). The study aimed to determine the relationship of GABA transporter expression to known patterns of hippocampal hyperexcitability and extracellular GABA levels. GAT-1 was localized in axon terminals and small neuronal cell bodies, and in non-sclerotic hippocampi was strongly expressed throughout all regions of the hippocampal formation. In the epileptogenic hippocampus exhibiting Ammon’s horn sclerosis, immunoreactivity was reduced in the sclerotic regions CA3 and CA1, and around the cell bodies of dentate granule cells, but was increased along granule cell dendrites. GAT-3 was weakly expressed, if at all, in non-sclerotic hippocampi, but more prominently expressed in sclerotic hippocampi. GAT-3 expression was confined to cells resembling protoplasmic astrocytes, which were located in regions of relative neuronal sparing such as the dentate gyrus and hilus of the sclerotic hippocampus. The reduction in GAT-1 around granule cells in the sclerotic hippocampus could explain the prolonged GABA responses in this region. The loss of GAT-1 (a marker of GABAergic terminals) would also suggest a reduced GABAergic input to the granule cells, thus facilitating hyperexcitability. The increased GAT-3 expression in astrocytes in regions of relative neuronal sparing in the sclerotic hippocampus may be related to the overall low levels of extracellular GABA observed in the sclerotic hippocampus and their increased excitability.     

Role of OLR1 and its regulating hsa-miR369-3p in Alzheimer's disease: genetics and expression analysis

The oxidized LDL receptor 1 gene (OLR1) rs1050283 single nucleotide polymorphism (SNP) has been previously shown to be associated with Alzheimer's disease (AD). An association analysis of OLR1 was carried out in a population of 443 patients with AD as compared with 393 age-matched controls. In addition, an expression analysis of OLR1 and its regulatory hsa-miR369-3p was performed in peripheral mononuclear blood cells (PBMC) from 20 patients and 15 controls. Logistic regression analysis, adjusted for gender and apolipoprotein E (ApoE) status, showed a statistically significant association of OLR1 rs1050283 under the assumption of a dominant model (CC and CT individuals versus TT: p = 0.014, OR: 1.50, 95%CI: 1.08-2.08) and a genotypic model (TC versus TT: p = 0.002, OR: 1.61, 95%CI: 1.14-2.26). No significant differences in OLR1 expression was observed between patients and controls (p > 0.05). However, stratifying patients according to the rs1050283 status, significantly decreased relative PBMC expression levels of OLR1 were observed in carriers of CC+CT genotypes as compared with TT carriers (0.13 ± 0.013 versus 0.46 ± 0.028, p = 0.022), whereas no differences in relative expression levels of the hsa-miR369-3p were observed (p > 0.05). The effect observed was not due to the presence of the ApoE ε4 allele. The OLR1 rs1050283 SNP likely acts as a risk factor for sporadic AD. The presence of at least one C allele is associated with a decreased expression of OLR1 mRNA in the absence of hsa-miR369-3p de-regulation, suggesting that the presence of the polymorphic allele influences the binding of hsa-miR369-3p to its 3'UTR consensus sequence. Nevertheless, the limited power of the study requires further investigations with a larger sample size.     

Seizure,neurotransmitter release,and gene expression are closely related in the striatum of 4-aminopyridine-treated rats

The present experiments aimed to compare the length of seizure activity with the time-related increase of transmitter release and the induction of c-fos gene expression in the striatum of the rat. Anesthetized Wistar rats were intraperitoneally treated with 7 mg/kg 4-aminopyridine, and the transmitter levels in the striatum were measured by means of in vivo microdialysis, 30, 60, 90, 120, and 150 min following the treatment. Striatal and neocortical electric activity was monitored with depth and surface electrodes, respectively. The expression level of the c-fos gene was estimated by counting the striatal c-fos-immunostained cell nuclei at the time intervals of the microdialysis. 4-aminopyridine elicited high-frequency seizure discharges in the EEG and significantly increased glutamate, aspartate, GABA, serotonin, noradrenaline, and dopamine levels in the extracellular dialysates. The number of c-fos-stained cell nuclei in the striatum displayed a prolonged increase, showing significantly elevated numbers throughout the experiment. The increase of c-fos expression in time correlated best with the increase of glutamate release, which was also significantly elevated at every sampling time. The GABA release, culminating at 60 min after the seizure onset, correlated best with the cessation of the electrographic seizure. Aspartate, norepinephrine, serotonin, and dopamine displayed transient but significant elevations. We conclude that glutamate plays the essential role (most probably through ionotropic and metabotropic receptors) in the extracellular signaling, which eventually leads to intracellular cascades and c-fos gene expression in the striatum during convulsions.     

GDNF, RET and GFRalpha-1-3 mRNA expression in the developing human spinal cord and ganglia.

The identification of endogenous neurotrophic factors and their receptors in human spinal cord is important not only to understand development, but also in the consideration of possible future therapies for neurodegenerative disorders and trauma. Using in situ hybridization, the expression of glial cell line-derived neurotrophic factor (GDNF), neurturin (NTN), persephin (PSP), GFRalpha-1, GFRalpha-2, GFRalpha-3 and RET mRNA in human fetal spinal cord was studied. Strong GDNF mRNA hybridization signal, presumably restricted to Clarke's nucleus, was detected in the thoracic spinal cord. mRNA encoding GFRalpha-1 was expressed in the entire spinal cord gray matter with particularly high expression in the ventral horn. GFRbeta-1 was also expressed more weakly in dorsal root ganglia. NTN and persephin mRNA were not detected in either the fetal spinal cord or the dorsal root ganglia. mRNA coding for GFRalpha-2, however, was found in most cells of the spinal cord gray matter. A strong expression of GFRalpha-3 mRNA was detected in dorsal root ganglia cells and Schwann cells. The transducing receptor RET was expressed strongly in motorneurons and dorsal root ganglion neurons. We conclude that basic features concerning the role of the GDNF family of ligands and their receptors revealed in rodents applies to humans.     

Interferon-beta differentially regulates expression of the IL-12 family members p35, p40, p19 and EBI3 in activated human dendritic cells

Interferon-beta is thought to provide clinical improvement to multiple sclerosis (MS) patients, in part, through its ability to suppress the generation of IL-12-dependent autoimmune T helper type 1 (Th1) cells by monocyte-derived dendritic cells (DC). We now describe how pre-incubation with 1000 U/ml of IFN-beta differentially regulates expression of multiple IL-12 family members in activated, immature human DC, inhibiting CD40/IFN-gamma-induced p35 and p40 message levels, while enhancing p19 and Epstein-Barr virus-induced gene 3 (EBI3) levels. IFN-beta-mediated inhibition of p40 mRNA and augmentation of p19 mRNA both require de novo protein synthesis. These findings indicate that IFN-beta will be found to have contrasting effects on DC secretion of the various IL-12 family homo- and heterodimers.