Laminin expression by glial fibrillary acidic protein positive cells in human gliomas

Extracellular matrix components are regarded as important substrates for invasive tumor cells. The present work focuses on the expression of laminin in the brain in response to invading brain tumors. Biopsies obtained from tissue macroscopically evaluated as the border zone between tumor and normal brain, in 5 patients undergoing surgery for glioblastoma multiforme, were examined by immunocytochemistry and scanning confocal microscopy for the expression of laminin and glial fibrillary acidic protein. Laminin was mainly found in all the specimens associated with the basal lamina of blood vessels, but a variable degree of punctate laminin deposits were also observed in the parenchyma not associated with blood vessels. In the specimens with substantial deposits, scanning confocal microscopy showed that some of the laminin co-localized with intracellular glial fibrillary acidic protein. Punctate deposits of laminin were also seen in an intracranial BT4C rat glioma model, where it was particularly abundant in the brain/tumor confrontation zone. Previous in vitro studies have shown that laminin, among several extracellular matrix components, represent a highly permissive substrate for glioma cell migration. The presented results indicate that laminin can be produced by glial fibrillary acidic protein positive cells during glioma cell invasion in humans. This glycoprotein may thus represent one important substrate among many, which contribute to the invasive phenotype of gliomas.     

Gene amplification in malignant human gliomas: clinical and histopathologic aspects

Gene amplification occurs in 45-50% of malignant human gliomas (MHG). In the present study, 64 genetically characterized gliomas were evaluated to determine if tumors with amplification of the epidermal growth factor receptor (EGFR), N-myc, c-myc, or gli genes had distinctive histopathologic features. There was no significant difference in age (p = 0.10) or gender (p = 0.78) between patients whose tumors contained amplified genes and those whose tumors did not exhibit this characteristic. Although the patients with amplified genes in their tumors survived slightly longer than patients whose tumors had no detectable gene amplification, these differences were not statistically significant (p = 0.21). The 28 tumors with amplification included 24/48 (50%) glioblastoma multiforme, 2/6 (33%) anaplastic astrocytomas and 2/5 (40%) gliosarcomas. No amplification was seen in one oligodendroglioma, three anaplastic mixed gliomas or one giant cell glioblastoma multiforme. Necrosis and endothelial proliferation were equally prevalent among tumors with and without amplification. Comparison of tumors with gene amplification and tumors without this characteristic revealed similar distributions of most morphologic cells types. Although prominent perivascular lymphocytic infiltrates were more frequent in tumors without amplification, this association was of borderline significance statistically. In situ hybridization of tumors with amplification using an EGFR mRNA probe showed intense labeling of different neoplastic cell types including fibrillary and protoplasmic astrocytes, gemistocytes, anaplastic cells, and multinucleated giant cells. Non-neoplastic cells such as hyperplastic endothelium within the tumors did not express detectable EGFR mRNA. These studies demonstrate that (a) cells with quite different morphology within the same tumor can contain the same genetic alteration; (b) tumors of identical histological appearance may have arisen and evolved by different molecular mechanisms; and (c) molecular analyses are necessary to evaluate gene amplification in MHG since this characteristic cannot be accurately predicted by the morphologic or clinical criteria used in this study.     

Fatty acid binding protein 4 is expressed in distinct endothelial and non-endothelial cell populations in glioblastoma

O. Cataltepe, M. C. Arikan, E. Ghelfi, C. Karaaslan, Y. Ozsurekci, K. Dresser, Y. Li, T. W. Smith and S. Cataltepe (2012) Neuropathology and Applied Neurobiology 38, 400–410 Fatty acid binding protein 4 is expressed in distinct endothelial and non‐endothelial cell populations in glioblastoma Aims: Glioblastoma (GBM) is the most common and aggressive primary brain tumour in adults. Angiogenesis and vasculogenesis play key roles in progression of GBMs. Fatty acid binding protein 4 (FABP4) is an intracellular chaperone for free fatty acids. FABP4 is detected in microvascular endothelial cells (ECs) in several normal tissues and promotes proliferation of ECs. The goal of this study was to characterize the tissue distribution pattern of FABP4 in GBMs. Methods: Immunohistochemistry for FABP4 was performed on paraffin‐embedded tumour sections and the intensity and distribution of FABP4 immunoreactivity were analysed. Double immunofluorescence was employed for detailed characterization of FABP4‐positive cells. Results: FABP4 immunoreactivity was absent in normal brain tissue sections. FABP4‐positive cells were detected in 33%, 43%, 64% and 89% of Grade I, Grade II, Grade III and Grade IV glial tumours, respectively. Thus, the percentage of FABP4‐positive cells in GBMs was significantly higher than lower‐grade gliomas. In general, FABP4‐expressing cells were distributed in a non‐homogenous pattern, as ‘hot spots’ in glial tumours. FABP4 expression was detected in a subset of vascular ECs as well as some non‐ECs. Conclusion: FABP4 is expressed in a significantly higher percentage of GBMs in comparison to both normal brain tissues and lower‐grade glial tumours. FABP4 is expressed in some tumour ECs as well as non‐ECs in glial tumours. As FABP4 promotes proliferation of ECs, detection of FABP4 in GBM‐ECs, but not normal brain ECs suggests that FABP4 may play a role in the robust angiogenesis associated with GBMs.     

Expression and distribution of id helix-loop-helix proteins in human astrocytic tumors

The Id family of helix-loop-helix proteins is involved in a variety of processes, such as development, proliferation, and angiogenesis. In this study, we investigated the expression pattern of Id1, Id2, and Id3 in surgical specimens of human glial tumors. Western blot analysis demonstrated that all three Id proteins were expressed in astrocytic tumors. Expression levels in high-grade tumors were higher than in low-grade tumors. Immunohistochemical analysis confirmed that many of the tumor astrocytes exhibited strong Id1-3 IR. In contrast, in adult human normal brain, Id expression was low both in resting astrocytes and in endothelial cells. In tumor cells, Id proteins displayed cytoplasmic as well as nuclear localization. Id1-3 IR scores in tumor cells were positively correlated with proliferation indices. Moreover, Id1-3 IR was detected in endothelial cells of the astrocytic tumor blood vessels. The vascular Id1-3 expression correlated positively with tumor vascularity and grade. These results support the role of the Id gene family in the enhanced proliferative potential of tumor astrocytes. The evidence also supports the involvement of the Id gene family in tumor angiogenesis, a process that critically influences the malignant behavior of glial tumors.     

大鼠局灶性脑缺血/再灌注后Ku70mRNA的表达

目的　研究大鼠脑缺血 /再灌注后 Ku70 m RNA的表达 ,以了解脑缺血 /再灌注后缺血半暗带 DNA修复酶的动态变化。方法　健康雄性 Wistar大鼠 ,体重 ( 2 5 0± 3 0 ) g,随机分为 2组即造模组和假手术组。造模组大鼠用线栓法成功制作可复流的 MCAO模型 ,2 h后再灌注。再灌注 6、2 4、48h时将大鼠断头取脑 ,作冷冻切片。通过原位杂交方法及末端标记法检测 Ku70 m RNA的表达及 Tunel阳性细胞数。结果　造模组脑缺血 /再灌注各时点 Ku70 m RNA表达均较假手术组明显减少 ( P <0 .0 1 )。随再灌注时间的增加 ,脑缺血半暗带 Ku70 m RNA的表达逐渐减少 ( P<0 .0 5 ) ,造模组脑缺血半暗带 Tunel阳性细胞数逐渐增加 ( P<0 .0 1 )。结论　 Ku70下降可能在脑缺血损伤所致的细胞凋亡中起重要作用。     

Livin在人脑胶质瘤中的表达及生物学意义

目的探讨Livin表达与人脑胶质瘤病理分级、分类和预后的相关性。方法采用免疫组化SP法,检测Livin在41例人脑胶质瘤和10例正常人脑组织中的表达。结果Livin在10例正常脑组织中均不表达,而在41例胶质瘤组织中表达阳性率为87.8%(P<0.01)。Livin表达与胶质瘤病理分级明显相关(P<0.05),与胶质瘤病理类型、是否复发无明显相关(P>0.05)。结论Livin在人脑胶质瘤组织中表达上调,提示Livin与胶质瘤病程发展、恶性程度明显相关,在胶质瘤的发生和发展中起重要作用。     

TEM8在人脑胶质瘤中的表达及其意义

目的 探讨肿瘤内皮标记物8（TEM8）在人脑胶质瘤组织中的表达特点及其意义。方法 采用免疫组化法检测84例脑胶质瘤及15例颅脑损伤减压手术切除的正常脑组织标本TEM8的表达,并分析TEM8表达与胶质瘤临床病理特征及预后的关系。结果 胶质瘤TEM8高表达率（47.6%,40/84）明显高于正常脑组织（6.7%,1/15;P<0.01）。高级别胶质瘤TEM8高表达率（64.4%,29/45）显著高于低级别胶质瘤（28.2%,11/39;P<0.01）。TEM8表达与胶质瘤患者性别,年龄,肿瘤部位和大小无关（P>0.05）。TEM8高表达胶质瘤患者中位生存期（24.5个月）明显长于TEM8低表达胶质瘤患者中位生存期（36.0个月;P<0.05）。结论 胶质瘤组织TEM8呈高表达,并且与胶质瘤级别和预后显著相关。     

Skp2、P27kip1和PTEN在人脑胶质瘤中的表达及其相互关系的研究

目的探讨S期激酶相关蛋白2（skp2）、细胞周期素依赖性激酶抑制蛋白P27^kip1和抑癌基因蛋白PTEN表达与人脑胶质瘤发生、发展的关系。方法用免疫组化SP法检测52例人脑胶质瘤和8例正常脑组织标本中Skp2、P27^kip1和PTEN蛋白的表达。结果Skp2在8例正常脑组织中全部表达阴性。在52例胶质瘤标本中随着肿瘤恶性程度增高而表达增强。在低、高级别胶质瘤中的阳性率分别56％和81．5％，三者之间的表达水平差异有显著性意义（P〈0．001）。P27^kip1和PTEN在正常脑组织中表达均为强阳性，随着肿瘤恶性程度增高而表达减弱，P27^kip1和PTEN各自在低、高级别人脑胶质瘤中阳性率分别96％、77．8％和80％、55．6％。三者之间的表达水平差异有显著性意义（P〈0．01）。在52例胶质瘤标本中，Skp2表达与P27^kip1（r=-0．490，P〈0．01）和肿瘤抑制蛋白PTEN（r=-0．489，P〈0．01）表达呈负相关，PTEN表达与P27^kip1表达呈正相关（r=-0．802，P〈0．01）。结论人脑胶质瘤中Skp2蛋白过表达与P27^kip1降解及PTEN蛋白低表达有关，提示Skp2蛋白过表达可能是人脑胶质瘤发生和发展的一个重要原因。     

Cullin7蛋白在人脑胶质瘤中的表达及临床意义

目的 探讨Cullin7蛋白在人脑胶质瘤中的表达及临床意义。方法 选取2013年1月至2018年12月手术切除脑胶质瘤标本60例,其中WHO分级Ⅰ级12例,Ⅱ级18例,Ⅲ级14例,Ⅳ级16例。另选取重型颅脑损伤内减压术切除正常脑组织10例作为对照组。采用免疫组化染色、免疫印迹法法检测Cullin7蛋白表达情况。51例随访46个月,9例失访;采用Kaplan-Meir法分析和Log-rank检验分析生存曲线。结果 高级别胶质瘤Cullin7蛋白阳性表达率（66.7%）明显高于低级别胶质瘤（36.7%;P<0.05）,而低级别胶质瘤Cullin7蛋白阳性表达率明显高于对照组（0%;P<0.05）。Cullin7高表达病人生存期较低表达病人明显缩短（P<0.05）。结论 Cullin7蛋白在脑胶质瘤中的表达与肿瘤恶性程度呈正相关,与病人生存期呈负相关。     

Diazepam binding inhibitor-like immunoreactivity(51–70): distribution in human brain, spinal cord and peripheral tissues

We have used specific radioimmunoassay to describe the distribution of diazepam binding inhibitor-like immunoreactivity (DBI-IR(51–70)) in human post-mortem tissues. In brain, highest concentrations were found in the cerebellum, amygdala, hippocampus, hypothalamus and substantia nigra. In the spinal cord, DBI-IR(51–70) was evenly distributed. In peripheral tissues, highest concentrations were found in the liver and kidney. Chromatographic analysis revealed several molecular forms of DBI-IR(51–70) the major form being of greater molecular weight and hydrophobicity than the synthetic fragment peptide. In peripheral tissues, but not in the CNS, a small peak of immunoreactivity was indistinguishable form the synthetic peptide. DBI-IR(51–70) is therefore widespread, but tissue processing may be different.     

Proliferating cell nuclear antigen (PCNA): expression in samples of human astrocytic gliomas

In this retrospective study, 55 astrocytic tumours were stained with monoclonal antibody PC10 which recognizes the proliferating cell nuclear antigen (PCNA) in formalin fixed, paraffin-wax embedded sections. All the cases were graded using the Daumas-Duport system and the PCNA labelling indices (LIs) were correlated with tumour grades. Mean PCNA LI was 4.1% in the grade II, 8.1 % in the grade III and 26.1% in the grade IV group. Six juvenile and cerebellar (grade I) astrocytomas had a mean PCNA LI of 5.6%. In general PCNA LI increased with tumour grade, but there was considerable variation of LIs especially in grade IV tumours which often had very high PCNA LIs (up to 72.7%). PC10 may be a useful complementary technique in surgical neuropathology, but the significance of the high LIs, seen in a proportion of glioblastomas, needs to be further determined.     

AEBP1在胶质母细胞瘤中的表达及临床意义

目的 探讨脂肪细胞增强剂结合蛋白1（AEBP1）在胶质母细胞瘤（GBM）中的表达及临床意义。方法 采用生物信息学分析方法,利用ONCOMINE、GEPIA和STRING数据库评估AEBP1在GBM中的表达情况及其预后价值。结果 AEBP1在GBM组织中表达水平显著高于正常组织。生存分析表明,AEBP1表达水平与GBM总体生存率呈显著负相关。KEGG分析显示与AEBP1紧密相关的蛋白质主要参与肿瘤转录失调以及局部粘连信号通路。结论 我们应用生物信息学分析显示AEBP1可能参与GBM发生、发展,AEBP1表达水平增高可能是诊断GBM的重要指标,并有望成为预后指标。然而,AEBP1在GBM中的具体作用机制及其作为预后评估和治疗靶点的价值有待进一步研究     

Neuronal effects of SP600125 pretreatment in a rat model of cerebral ischemia/reperfusion injury Inhibited down-regulation of DNA repair protein

BACKGROUND： Recent studies have shown that the selective inhibitor of c-Jun N-terminal kinases （JNKs） signaling pathway, SP600125, exhibits neuronal protective effects in a rat model of brain ischemia/reperfusion. OBJECTIVE： To determine the mechanisms of neuroprotective effects of SP600125 in a rat model of brain ischemia/reperfusion, and determine the role of the JNK signaling pathway in SP600125-induced effects. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Animal Experiment Center, Medical School of Xi＇an Jiaotong University from June 2007 to September 2008. MATERIALS： SP600125 was provided by Biosource, USA; rabbit anti-phospho-JNK （Thr183/Tyr185） polyclonal antibody from Cell Signaling Technology, USA; rabbit anti-X-ray repair cross-complementing protein 1 （XRCC1） and anti-Ku70 polyclonal antibodies from Santa Cruz Biotechnology, USA; and TUNEL kit from Beijing Huamei Biology, China. METHODS： A total of 108 male, 4-month-old, Sprague Dawley rats were randomly assigned to three groups, with 36 rats per group. The sham operation group and ischemia/reperfusion group （I/R group） were intracerebroventricularly injected with 10 μL 1% DMSO. The SP600125-treated group （pre-SP group） was given 10 μL SP600125 （3 μg/μL）. Thirty minutes later, brain ischemia was induced in the I/R and pre-SP groups using the four-vessel occlusion method. Specifically, whole brain ischemia was induced for 6 minutes, and the clips were released to restore carotid artery blood flow. Rats from each group were observed at 2, 6, 12, 24, 48, and 72 hours, with 6 rats for each time point. The sham operation group was treated with the same surgical exposure procedures, with exception of occlusion of the carotid artery. MAIN OUTCOME MEASURES： Hematoxylin-eosin staining was used to observe neuronal survival in the hippocampal CA1 region, TUNEL was used to detect apoptosis in the hippocampal CA1 region, and immunohistochemistry was used to detect expression of phospho-JNK, XRCC1, and Ku70. RESULTS： Following brain ischemia/reperfusion, neuronal survival significantly decreased, and the number of apoptotic cells significantly increased （P 〈 0.01）. Compared with the I/R group, neuronal survival significantly increased in the pre-SP group, and the number of apoptotic cells significantly decreased （P 〈 0.01）. Expression of phospho-JNK increased, and XRCC1 and Ku70 significantly decreased （P 〈 0.05） following ischemia/reperfusion. Compared with the I/R group, expression of phospho-JNK decreased, and XRCC1 and Ku70 significantly increased in the pre-SP group （P 〈 0.05）. Correlation analysis revealed an inverse correlation between phospho-JNK gray value and XRCC1 and Ku70 gray values in the hippocampal CA1 region （r = -0.983, -0.953, P 〈 0.01）. CONCLUSION： SP600125 treatment decreased apoptosis induced by global brain ischemia/reperfusion in the rat hippocampal CA1 region. Results suggested that the neuroprotective effects were due to inhibited phosphorylation of JNK and reduced down-regulation of XRCC1 and Ku70.     

骨桥蛋白与整合素β3在脑胶质瘤中的表达及其意义

目的探讨骨桥蛋白（OPN）、整合素β3与胶质瘤恶性程度的关系,及OPN与整合素β3之间的相关性.方法采用免疫组化染色、逆转录-聚合酶链反应（RT-PCR）及免疫印迹法（Western B1ot）等方法检测正常人脑组织和胶质瘤组织中OPN、整合素β3的mRNA及蛋白表达.结果正常脑组织中无OPN、整合素β3表达,而胶质瘤细胞膜、细胞质及血管内皮细胞中有表达.随着脑胶质瘤病理分级的增高,OPN与整合素β3的表达显著性增高（P＜0.05）.OPN与整合素β3的mRNA（r=0.990,P＜0.05）及蛋白（=0.943,P＜0.05）表达均呈正相关.结论OPN与整合素β3在人脑胶质瘤组织中的表达强度与其恶性程度相关,且OPN和整合素β3的表达之间有内在联系.     

脑胶质瘤中survivin蛋白表达情况及其与肿瘤恶化程度关系的研究

目的 探讨survivin蛋白在脑胶质瘤的表达情况及其与肿瘤恶性程度之间的关系.方法收集脑胶质瘤患者组织蜡块90例,其中Ⅰ级30例,Ⅱ级30例,Ⅲ级～Ⅳ级30例.另取10例因颅脑创伤行内减压的正常脑组织蜡块作为对照.应用免疫组织化学染色方法检测脑胶质瘤组织survivin蛋白的表达情况. 结果 胶质瘤细胞胞浆中有survivin蛋白的表达,且随着肿瘤级别的增高,survivin蛋白的表达增强.其表达阳性率在Ⅰ级组中为16.67%(6/30),在Ⅱ级组中为46.67%(14/30),在Ⅲ级～Ⅳ级组中为86.67%(26/30),差异有统计学意义(P<0.05).而在正常脑组织中survivin的表达为阴性. 结论 Survivin在脑胶质瘤的恶变过程中起重要作用,针对survivin的靶向治疗有望成为治疗脑胶质瘤的一个新的途径.