Geminin: a good prognostic factor in high-grade astrocytic brain tumors

BACKGROUND: Geminin is a nuclear protein that belongs to the DNA replication inhibitor group. It inhibits DNA replication by preventing Cdt1 from loading minichromosome maintenance protein onto chromatin, as is required for DNA replication. For this study, the authors investigated geminin expression in high-grade astrocytic tumors, including anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM), with a view to predicting clinical outcomes on this basis in patients with these malignant brain tumors. METHODS: Immunohistochemistry was used to detect geminin expression in 51 patients with high-grade astrocytic tumors (19 AA and 32 GBM). Samples were categorized by taking the median value as the cut-off point for constructing Kaplan-Meier curves. The relation of geminin expression to clinical outcome in these malignant brain tumors was analyzed by using the Kaplan-Meier method and a Cox proportional hazards regression model. RESULTS: Geminin was expressed in all high-grade astrocytomas (mean geminin labeling index [LI], 24.90%). Kaplan-Meier curves showed that the group with higher geminin LI (>or=22.50%) had a better prognosis than the group with lower LI (<22.50%; P = .0296). Similarly, the Cox regression analysis showed that geminin expression has a significant correlation with survival in patients with high-grade astrocytoma (P = .0278), especially in an early stage. CONCLUSIONS: Although it is an inhibitor of DNA proliferation and, thus, is a cell cycle inhibitor, geminin expression was found in all malignant astrocytic tumors. The geminin LI was a significant predictive factor of outcomes in patients with high-grade astrocytoma, with higher expression indicating a good prognosis.     

Expression of tenascin-C in various human brain tumors and its relevance for survival in patients with astrocytoma

BACKGROUND: Tenascin-C (TN-C), a large extracellular matrix (ECM) glycoprotein with a molecular weight of 180-250 kilodaltons, is present in several normal adult tissues. TN-C is up-regulated during embryogenesis, in wound healing, and in tumor tissues. Glioblastoma multiforme (GBM) is the most frequent and malignant astrocytic tumor comprised of poorly differentiated, neoplastic astrocytes. Recently, TN-C-based radioimmunotherapy was administered to patients with GBM. METHODS: In the current study, the authors used immunohistochemistry to conduct a systematic investigation of TN-C distribution patterns in normal human brain tissue and in a large variety of brain tumors (n = 485 tumors). Immunoreactivity for TN-C was assessed with regard to its localization within tumor cells, blood vessels, and ECM using three different monoclonal antibodies (clones BC2, BC4, and TN2). RESULTS: In control human brains, a significant difference was noted in the expression of TN-C when comparing gray with white matter using either Western blot analysis or immunohistochemistry. TN-C was found in the white matter of the frontal, temporal, parietal, and occipital lobes and in the hippocampus, where the immunoreaction was especially strong in the hippocampal formation. In 181 astrocytomas of different grades (World Health Organization [WHO] Grade 2-4), TN-C immunopositivity was seen to varying degrees in the cellular and stromal components of the tumor and in tumor-associated vessels. Glioblastomas (n = 113 tumors) showed strong immunopositivity in the vessels and moderate immunopositivity of the ECM. A statistically significant reduction of TN-C immunopositivity in tumor-associated vessels or ECM was observed in anaplastic astrocytomas (WHO Grade 3) compared with GBM (WHO Grade 4). A Kaplan-Meier analysis showed that patients who had GBM lesions that lacked TN-C immunopositivity in the ECM had a significantly longer survival (median, 28 months; standard error, 7.8 months) (n = 12 patients) compared with patients who had GBM lesions with TN-C immunopositivity (median, 12 months; standard error, 1.6 months) (n = 87 patients). In meningiomas (n = 24 tumors), the neoplastic cells, the ECM of the tumor, and the vessels were TN-C negative. In schwannomas (n = 31 tumors), the tumor cells were TN-C negative; whereas, in > 50% of tumors, the vessels and the ECM of regressively altered tumor areas were positive. In metastatic carcinomas (n = 53 tumors), the tumor cells were negative; seldom were vessels stained positive for TN-C. Focal areas of the ECM, often accompanied with fibrotic changes, were immunopositive for TN-C. CONCLUSIONS: The most constant TN-C immunopositivity was noted in the ECM of the fibrotic stroma in highly malignant brain tumors and along the tumor border, especially in high-grade astrocytomas. The current results suggest that TN-C expression may be correlated with the grade of malignancy in astrocytic tumors and that the presence or absence of TN-C expression in the stroma of astrocytic tumors may play a not yet clearly understood role in shortening or prolonging, respectively, the survival of patients.     

星形细胞肿瘤DEK的表达及其与病理分级的关系

目的:检测星形细胞肿瘤组织中DEK的表达,分析其与病理分级之间的关系。方法:应用免疫组化技术并用图像分析系统检测各级别星形细胞肿瘤组织及脑组织中DEK的表达水平。结果:各组免疫组化染色阳性率分别为:肿瘤组织（86.6%）,其中毛细胞型星形细胞瘤(WHO I级66.7%),弥漫性星形细胞瘤（WHO II级84.2%）,间变性星形细胞瘤（WHO III级93.3%）,胶质母细胞瘤（WHO IV级100.0%）;脑组织（33.3%）。各组免疫组化染色强度分别为:肿瘤组织 23.57±8.12,其中毛细胞型星形细胞瘤14.23±5.31,弥漫性星形细胞瘤19.52±6.68,间变性星形细胞瘤32.12±13.56,胶质母细胞瘤36.92±15.61;脑组织11.61±1.85。DEK在肿瘤组织中的表达显著高于其在脑组织中的表达（P<0.05）。结论:DEK的过表达与星形细胞肿瘤的发生密切相关,并且与肿瘤的病理分级也密切相关;DEK表达改变,为星形细胞肿瘤临床诊断、治疗和预后判断提供了新思路。     

Expression of phosphoprotein enriched in astrocytes 15 kDa (PEA-15) in astrocytic tumors: a novel approach of correlating malignancy grade and prognosis

Phosphoprotein enriched in astrocytes 15 kDa (PEA-15) is a multifunctional protein that was first identified in brain astrocytes and that has subsequently been shown to be expressed in different tissues. Despite its many important roles, the clinical significance of PEA-15 expression levels in astrocytic tumors has yet to be properly defined. We studied the PEA-15 expression pattern of 65 patients [diagnosed according to World Health Organization (WHO) criteria] with diffuse astrocytoma (WHO grade II), anaplastic astrocytoma (grade III), and glioblastoma (grade IV). PEA-15 expression levels were immunohistochemically measured and categorized as no, low, or high expression. All tumors expressed PEA-15 in our study. Twenty-three (35.4%) and 42 (64.6%) tumors expressed low and high PEA-15 levels, respectively. In grade II astrocytoma (diffuse astrocytoma) and grade III astrocytoma (anaplastic astrocytoma), 100% and 88.9% of patients expressed high PEA-15 levels, respectively, while a smaller number (50%) of patients with grade IV astrocytoma (glioblastoma) expressed high PEA-15 levels. PEA-15 expression level was inversely associated with WHO grade (P = 0.0006). Next, we evaluated prognosis and PEA-15 expression levels in 43 patients with high-grade astrocytomas based on the following parameters: age, gender, WHO grade, surgical resection extent, MIB-1 labeling index (LI), and PEA-15 expression level. Multivariable analyses revealed that high PEA-15 expression level displayed a significant correlation with longer overall survival (OS) in high-grade astrocytomas (P = 0.0024). Patients with total resection survived significantly longer (P = 0.0044) than those with lower resection extent, while patients with MIB-1 labeling index ≤25% indicated significant (P = 0.0434) correlation with OS as well. In conclusion, PEA-15 expression level was inversely associated with WHO grade and may serve as an important prognostic factor for high-grade astrocytomas.     

Human leukocyte antigen and antigen processing machinery component defects in astrocytic tumors.

PURPOSE: To determine the frequency of abnormalities in human leukocyte antigen (HLA) and antigen processing machinery (APM) component expression in malignant brain tumors. This information may contribute to our understanding of the immune escape mechanisms used by malignant brain tumors because HLA antigens mediate interactions of tumor cells with the host's immune system. EXPERIMENTAL DESIGN: Eighty-eight surgically removed malignant astrocytic tumors, classified according to the WHO criteria, were stained in immunoperoxidase reactions with monoclonal antibody recognizing monomorphic, locus-specific, and allospecific determinants of HLA class I antigens, beta2-microglobulin, APM components (LMP2, LMP7, TAP1, TAP2, calnexin, calreticulin, and tapasin), and HLA class II antigens. RESULTS: HLA class I antigens were lost in approximately 50% of the 47 glioblastoma multiforme (GBM) lesions and in approximately 20% of the 18 grade 2 astrocytoma lesions stained. Selective HLA-A2 antigen loss was observed in approximately 80% of the 24 GBM lesions and in approximately 50% of the 12 grade 2 astrocytoma lesions stained. HLA class I antigen loss was significantly (P < 0.025) correlated with tumor grade. Among the APM components investigated, tapasin expression was down-regulated in approximately 20% of the GBM lesions analyzed; it was associated, although not significantly, with HLA class I antigen down-regulation and tumor grade. HLA class II antigen expression was detected in approximately 30% of the 44 lesions analyzed. CONCLUSION: The presence of HLA antigen defects in malignant brain tumors may provide an explanation for the relatively poor clinical response rates observed in the majority of the T cell-based immunotherapy clinical trials conducted to date in patients with malignant brain tumors.     

Lack of Prognostic Significance of C-erbB-2 Expression in Low- and High- grade Astrocytomas

Background: Astrocytic tumors, the most common primary glial tumors of the central nervous system, areclassified from low to high grade according to the degree of anaplasia and presence of necrosis. Despite advancesin therapeutic management of high grade astrocytic tumors, prognosis remains poor. In the present study, thefrequency and prognostic significance of c-erb-B2 in astrocytic tumors was investigated. Materials and Methods:Records of 72 patients with low- and high-grade astrocytic tumors were evaluated. The expression of C-erbB-2was determined immunohistochemically and intensity was recorded as 0 to 3+. Tumors with weak staining (1+)or no staining (0) were considered Her-2 negative, while tumors with moderate (2+) and strong (3+) stainingwere considered Her-2 positive. Results: Of the 72 patients, 41 (56.9%) had glioblastoma (GBM), 10 (13.9%)had diffuse astrocytoma, 15 (20.8%) had anaplastic astrocytoma, 6 (8.3%) had pilocytic astrocytoma. C-erbB-2overexpression was detected in the tumor specimens of 17 patients (23.6%). Six (8.3%) tumors, all GBMs,exhibited strong staining, 2 (2.7%) specimens, both GBMs, exhibited moderate staining, and 9 specimens, 5 ofthem GBMs (12.5%), exhibited weak staining. No staining was observed in diffuse astrocytoma and pilocyticastrocytoma specimens. Median overall survival of patients with C-erbB-2 negative and C-erbB-2 positive tumorswere 30 months (95%CI: 22.5-37.4 months) and 16.9 months (95%CI: 4.3-29.5 months), respectively (p=0.244).Conclusions: Although there was no difference in survival, C-erbB-2 overexpression was observed only in theGBM subtype.     

Preirradiation endocrinopathies in pediatric brain tumor patients determined by dynamic tests of endocrine function

PURPOSE: To prospectively evaluate pediatric patients with localized primary brain tumors for evidence of endocrinopathy before radiotherapy (RT). METHODS AND MATERIALS: Seventy-five pediatric patients were evaluated with the arginine tolerance test and L-dopa test for growth hormone secretory capacity and activity; thyroid-stimulating hormone surge and thyrotropin-releasing hormone stimulation test for the hypothalamic-thyroid axis; the 1-microg adrenocorticotropin hormone (ACTH) and metyrapone test for ACTH reserve; and, depending on age, a gonadotropin-releasing hormone stimulation test to determine gonadotropin response. The study included 38 male and 37 female patients, age 1-21 years with ependymoma (n = 35), World Health Organization (WHO) Grade I-II astrocytoma (n = 18), WHO Grade III-IV astrocytoma (n = 10), craniopharyngioma (n = 7), optic pathway tumor (n = 4), and germinoma (n = 1). Seven patients receiving dexamethasone at the time of the evaluation were excluded from the final analysis. RESULTS: Of 68 assessable patient, 45 (66%) had evidence of endocrinopathy before RT, including 15 of 32 patients (47%) with posterior fossa tumors. Of the 45 patients, 38% had growth hormone deficiency, 43% had thyroid-stimulating hormone secretion abnormality, 22% had an abnormality in ACTH reserve, and 13% had an abnormality in age-dependent gonadotropin secretion. CONCLUSION: The incidence of pre-RT endocrinopathy in pediatric brain tumor patients is high, including patients with tumors not adjacent to the hypothalamic-pituitary unit. These data suggest an overestimation in the incidence of radiation-induced endocrinopathy. Baseline endocrine function should be determined for brain tumor patients before therapy. The potential for radiation-induced endocrinopathy alone cannot be used as an argument for alternatives to RT for most patients. Pre-RT endocrinopathy may be an early indicator of central nervous system damage that will influence the functional outcome unrelated to RT.     

The prostate stem cell antigen represents a novel glioma-associated antigen

Gliomas of WHO grades III-IV are malignant brain tumors mostly resistant to conventional therapies. Therefore, novel strategies for the treatment of gliomas are warranted. Although immunotherapy is gaining increased attention for the treatment of malignant gliomas and in particular of glioblastoma multiforme (GBM), this approach requires the identification of appropriate antigens. Our aim was to investigate the expression of the prostate stem cell antigen (PSCA), a highly N-glycosylated phosphatidylinositol (GPI)-anchored cell surface protein, in gliomas of different WHO grades in order to evaluate its potential as a diagnostic marker and as a target for immunotherapy. Tumor specimens and controls were assessed by quantitative RT-PCR, Western blotting and immunohistochemistry. The samples investigated in the study consisted of 210 human glial tumors, among which 31 were oligodendrogliomas, 9 ependymomas and 170 were astrocytomas (including 134 glioblastomas). PSCA was absent in normal brain tissue, but was detected in WHO grade III-IV gliomas. Weak PSCA protein expression was also recognized in some WHO grade I and WHO grade II tumors. The difference between WHO grade I-II tumors and WHO grade III-IV tumors was statistically significant (p<0.001). Our results suggest that increased PSCA expression levels are linked to gliomas of WHO grades III and IV, and may represent a suitable additional target for immunotherapy of gliomas.     

脑星形细胞肿瘤中FAK、Pyk2表达及其与血管生成的关系

背景与目的：非受体酪氨酸蛋白激酶家族成员FAK和Pyk2具有高度同源性,对肿瘤细胞增殖和侵袭具有重要的调控作用,但其是否参与肿瘤血管生成过程尚不明确。本研究旨在探讨FAK和Pyk2在脑星形细胞肿瘤中表达与血管生成的关系。方法：应用免疫组化法检测58例脑星形细胞肿瘤中FAK、Pyk2和血管内皮生长因子（VEGF）表达,并用CD31标记计数瘤内微血管密度。结果：FAK、Pyk2蛋白主要表达于肿瘤细胞胞浆,Pyk2阳性表达也见于肿瘤血管内皮细胞。在Ⅰ、Ⅱ、Ⅲ、Ⅳ级星形细胞肿瘤中,FAK阳性率分别为20.0%（1/5）、26.7%（4/15）、44.4%（8/18）、50.0%（10/20）,Pyk2阳性率分别为40.0%（2/5）、60.0%（9/15）、77.8%（14/18）、85.0%（17/20）;FAK和Pyk2阳性表达强度评分在Ⅱ级星形细胞肿瘤与Ⅲ、Ⅳ级星形细胞肿瘤中具有显著差异性（P〈0.05）。FAK、Pyk2表达与VEGF和微血管密度呈正相关,相关系数分别为rs=0.423（P=0.001）和rs=0.729（P〈0.005）。结论：FAK、Pyk2可能通过与VEGF的相互作用而参与脑星形细胞肿瘤的血管生成过程。     

Clinical significance of the 2016 WHO classification in Japanese patients with gliomas

In this study, we retrospectively compared the prognostic value of the 2016 WHO classification with the former classification in 387 patients with glioma treated at our institution. According to the new classification, diagnoses included oligodendroglioma with isocitrate dehydrogenase (IDH) mutation and 1p/19q co-deletion (5.4%), anaplastic oligodendroglioma with IDH mutation and 1p/19q co-deletion (3.4%), diffuse astrocytoma IDH-mutated (3.9%), anaplastic astrocytoma IDH-mutated (2.8%), glioblastoma IDH-mutated (7.8%), glioblastoma IDH-wildtype (58.4%), diffuse midline glioma H3 K27M mutation (2.6%), oligodendroglioma NOS (1.3%), anaplastic oligodendroglioma NOS (0.8%), diffuse astrocytoma IDH-wildtype (2.8%), and anaplastic astrocytoma IDH-wildtype (10.9%). The prognoses of IDH-mutated astrocytomas clearly varied according to tumor grade. However, we identified no survival difference between IDH-wildtype anaplastic astrocytomas and glioblastomas; additionally, these tumors showed similar gene expression profiles. After exclusion of those without 1p/19q co-deletion, patients with oligodendroglial tumors showed excellent survival regardless of tumor grade. Our evaluation of chromosomal aberrations suggests that the MAPK/PI3K pathway plays a role in acquired malignancy of astrocytic tumors, whereas TP53 participates in tumorigenesis. We suspect the RB pathway also plays a role in tumorigenesis of IDH-mutated gliomas. The new WHO classification more clearly reflects the tumorigenesis of gliomas and improves the prognostic power of classification.     

WT1 Clone 6F-H2 Cytoplasmic Expression Differentiates Astrocytic Tumors from Astrogliosis and Associates with Tumor Grade,Histopathology, IDH1 Status,Apoptotic and Proliferative Indices: A Tissue Microarray Study

Objectives: This tissue microarray (TMA) immunohistochemical (IHC) study elucidates the role of Wilms’ tumor 1 protein (WT1) in diagnosis and prognostication of astrocytic tumors. Methods: IHC was applied to 75 astrocytic lesions (18 astrogliosis and 57 astrocytic tumors) using antibodies directed against WT1 clone 6F-H2, isocitrate dehydrogenase 1(IDH1), Bcl2 and Ki67. WT1 IHC staining was evaluated and scored blindly by 2 pathologists. Bcl2 and Ki67 scores and labelling indices were assessed and IDH1 status determined. Statistical analysis was performed using the appropriate methodology. Results: WT1 cytoplasmic expression was detected in 89.5% of astrocytic tumors but not in astrogliosis. Positive WT1 differentiated astrocytic tumors (92.6% accuracy) and grade II diffuse astrocytomas (93.5% accuracy) from astrogliosis with high sensitivity, specificity and positive predictive values (p<0.001). Increased WT1 score significantly associated higher Bcl2 and Ki67 labelling indices, increasing WHO tumor grade and tumor’s histopathologic type (p<0.05) showing staining pattern variability by tumor entity and cell type. Glioblastomas, gliosarcomas and subependymal giant cell astrocytomas were the most frequently WT1 expressing tumors with frequent +3 WT1 score. About 21.4% of pilocytic astrocytomas had +3WT1 score in association with increased Bcl2 and Ki67 indices. Low WT1 scores in grade II and III diffuse astrocytomas were linked to the high frequency of IDH1 positivity, and were associated with low Bcl2 and Ki67 labelling indices. In glioblastomas, WT1 significantly associated poor prognostic variables: older age, negative-IDH1 status, high Bcl2 and Ki67 labelling indices (p=0.04, <0.001, =0.001 and     

Selective cancer-germline gene expression in pediatric brain tumors

Cancer-germline genes (CGGs) code for immunogenic antigens that are present in various human tumors and can be targeted by immunotherapy. Their expression has been studied in a wide range of human tumors in adults. We measured the expression of 12 CGGs in pediatric brain tumors, to identify targets for therapeutic cancer vaccines. Real Time PCR was used to quantify the expression of genes MAGE-A1, MAGE-A2, MAGE-A3, MAGE-A4, MAGE-A6, MAGE-A10, MAGE-A12, MAGE-C2, NY-ESO-1 and GAGE-1,2,8 in 50 pediatric brain tumors of different histological subtypes. Protein expression was examined with immunohistochemistry. Fifty-five percent of the medulloblastomas (n = 11), 86% of the ependymomas (n = 7), 40% of the choroid plexus tumors (n = 5) and 67% of astrocytic tumors (n = 27) expressed one or more CGGs. Immunohistochemical analysis confirmed qPCR results. With exception of a minority of tumors, the overall level of CGG expression in pediatric brain tumors was low. We observed a high expression of at least one CGG in 32% of the samples. CGG-encoded antigens are therefore suitable targets in a very selected group of pediatric patients with a brain tumor. Interestingly, glioblastomas from adult patients expressed CGGs more often and at significantly higher levels compared to pediatric glioblastomas. This observation is in line with the notion that pediatric and adult glioblastomas develop along different genetic pathways.     

p53 expression and subcellular survivin localization improve the diagnosis and prognosis of patients with diffuse astrocytic tumors

Purpose

Diffuse astrocytic tumors are the most frequently occurring primary central nervous system (CNS) tumors. Their histological sub-classification into diffuse astrocytoma (DA), anaplastic astrocytoma (AA) and glioblastoma (GB) is challenging and the available prognostic factors are limited to age and tumor subtype. Biomarkers that may improve the histological sub-classification and/or serve as prognostic factors are, therefore, urgently needed. The relationship between survivin and p53 in diffuse astrocytic tumor progression and survival is currently unclear. Here, we aimed to assess the relevance of these proteins in the accuracy of the histological sub-classification of these tumors and their respective treatment responses.

Methods

One hundred and thirty-three formalin-fixed paraffin-embedded diffuse astrocytic tumor samples were included. The tumor samples were histologically reviewed and subsequently assessed for p53 and survivin expression and the presence of the IDH R132H mutation by immunohistochemistry. p53 expression levels and survivin subcellular localization patterns were correlated with histological classification and clinical outcome.

Results

We found that age and histological subtype were the only features with a prognostic impact. In addition, we found that high p53 expression levels and a nuclear survivin localization correlated with the AA subtype, whereas cytoplasmic survivin localization correlated with the GB subtype. We also found that patients carrying tumors with a high cytoplasmic survivin expression, a high nuclear survivin expression or a high p53 expression, and who did not receive radiotherapy, exhibited poorer short-term and long-term overall survival rates.

Conclusions

Our data suggest that subcellular survivin localization and p53 expression may be employed as valuable tools to improve the accuracy of the histological sub-classification of diffuse astrocytic tumors. Patients whose tumors overexpress these proteins may benefit from radiotherapy, irrespective age and/or histological classification.

     

DEK蛋白在星形细胞肿瘤组织中的表达及意义

目的:探讨DEK蛋白表达与星形细胞肿瘤发生、发展的关系。方法:免疫印迹杂交法检测DEK蛋白在星形细胞肿瘤组织及正常脑组织中的表达水平。结果:DEK蛋白表达阳性率在肿瘤组织中为93.75%,DEK蛋白相对含量分别为:低级别肿瘤组织0.55±0.11,高级别肿瘤组织0.85±0.07;DEK蛋白在肿瘤组织中的表达显著高于其在正常脑组织中的表达（P<0.05）。结论:DEK蛋白表达与星形细胞肿瘤的发生、发展呈显著正相关,是评估星形细胞肿瘤恶性生物学行为的可靠指标。DEK作为凋亡抑制基因为星形细胞肿瘤的治疗提供了一个新靶点。     

微小染色体维持蛋白2 在非小细胞肺癌的表达及其预后意义

 目的　探讨微小染色体维持蛋白2（MCM2）在非小细胞肺癌（NSCLC）中的表达及其预后意义。方法　采用免疫组织化学方法检测73例NSCLC组织和10例正常肺组织中MCM2的表达,分析NSCLC中MCM2的表达与临床病理参数的关系及其对患者的预后评估价值。结果　正常肺组织中未见MCM2的表达,NSCLC组织中MCM2阳性表达率为87.7 %（46／73）,两者差异有统计学意义（P＜0.001）。 低分化的NSCLC中MCM2表达高于中高分化者（P＝0.008）,肺鳞状细胞癌中MCM2表达高于腺癌（P＝0.005）。MCM2高表达患者的死亡风险较低表达者明显升高（RR＝3.389,95 % CI＝1.803～7.146,P＜0.001）,累积生存率显著降低（P＝0.001）,多因素预后分析显示MCM2的表达是NSCLC的独立预后因素（P＝0.041）。结论　MCM2能很好地反映NSCLC细胞的增殖能力,MCM2检测对判断NSCLC的发展及预后具有一定的临床意义,为NSCLC的靶向治疗提供了潜在的靶点。