Maximal cardiopulmonary exercise testing in glioblastoma patients undergoing chemotherapy: assessment of feasibility, safety, and physical fitness status.

PURPOSE: Maximal cardiopulmonary exercise testing (max. CPET) provides the most accurate measurement of cardiorespiratory fitness. However, glioblastoma (GBM) patients often undergo less intensive tests, e.g., 6-min walk test or self-rating scales. This study aims to demonstrate feasibility and safety of max. CPET in GBM patients, concurrently evaluating their physical fitness status. METHODS: Newly diagnosed GBM patients undergoing adjuvant chemotherapy were offered participation in an exercise program. At baseline, max. CPET assessed cardiorespiratory fitness including peak oxygen consumption (VO2peak), peak workload, and physical work capacity (PWC) at 75% of age-adjusted maximal heart rate (HR). Criteria for peak workload were predefined based on threshold values in HR, respiratory quotient, respiratory equivalent, lactate, and rate of perceived effort. Data were compared to normative values. Adverse events were categorized according to standardized international criteria. Further, self-reported exercise data pre- and post-diagnosis were gathered. RESULTS: All 36 patients (median-aged 60; 21 men) met the predefined criteria for peak workload. Mean absolute VO2peak was 1750 ± 529 ml/min, peak workload averaged 130 ± 43 W, and mean PWC was 0.99 ± 0.38 W/kg BW, all clinically meaningful lower than age- and sex-predicted normative values (87%, 79%, 90%, resp.). Only once (3%) a minor, transient side effect occurred (post-test dizziness, no intervention needed). Self-reported exercise decreased from 15.8 MET-h/week pre-diagnosis to 7.2 MET-h/week post-diagnosis. CONCLUSION: Max. CPET in this well-defined population proved feasible and safe. GBM patients exhibit reduced cardiorespiratory fitness, indicating the need for tailored exercise to enhance health and quality of life. CPET could be essential in establishing precise exercise guidelines.

The Loss of 1p as a Reliable Marker of Progression in a Child with Aggressive Meningioma: A 16-Year Follow-Up Case Report.

BACKGROUND: Here, we present the case of a 32-year-old female with a progressing history of meningioma for 16 years starting with an ethmoidal lesion in 2002. The initial tumor specimen of this patient showed a deletion of the short arm of chromosome 1 through a translocation between chromosomes 1 and 11 (t[1; 11]) as well as additional chromosomal aberrations, including partial or complete monosomy of chromosomes 2, 6, 7, 11, 13, and 22. These molecular characteristics were already known to be associated with an aggressive course of the disease, and the patient was, therefore, included in a strict follow-up regime. From 2003 to 2019, the patient suffered multiple relapses and consecutive tumor resections. METHODS: Tumor specimen from 2017 was examined using a genome-wide methylation analysis as well as a whole-genome sequencing. RESULTS: These analyses confirmed the findings of 2002 and proved genetic alteration in the meningioma to be very stable over the time. Yet SMO and AKT1 mutations, which have been described to be paradigmatic in frontobasal meningioma, could not be found. CONCLUSIONS: Genetic characteristics seem to be very stable during progression of the disease. The loss of 1p represents to be a potential marker for the poor clinical course of our child meningioma. In 2019, our patient passed away due to the progress of her meningioma disease.

Mutational patterns and regulatory networks in epigenetic subgroups of meningioma.

DNA methylation patterns delineate clinically relevant subgroups of meningioma. We previously established the six meningioma methylation classes (MC) benign 1-3, intermediate A and B, and malignant. Here, we set out to identify subgroup-specific mutational patterns and gene regulation. Whole genome sequencing was performed on 62 samples across all MCs and WHO grades from 62 patients with matched blood control, including 40 sporadic meningiomas and 22 meningiomas arising after radiation (Mrad). RNA sequencing was added for 18 of these cases and chromatin-immunoprecipitation for histone H3 lysine 27 acetylation (H3K27ac) followed by sequencing (ChIP-seq) for 16 samples. Besides the known mutations in meningioma, structural variants were found as the mechanism of NF2 inactivation in a small subset (5%) of sporadic meningiomas, similar to previous reports for Mrad. Aberrations of DMD were found to be enriched in MCs with NF2 mutations, and DMD was among the most differentially upregulated genes in NF2 mutant compared to NF2 wild-type cases. The mutational signature AC3, which has been associated with defects in homologous recombination repair (HRR), was detected in both sporadic meningioma and Mrad, but widely distributed across the genome in sporadic cases and enriched near genomic breakpoints in Mrad. Compared to the other MCs, the number of single nucleotide variants matching the AC3 pattern was significantly higher in the malignant MC, which also exhibited higher genomic instability, determined by the numbers of both large segments affected by copy number alterations and breakpoints between large segments. ChIP-seq analysis for H3K27ac revealed a specific activation of genes regulated by the transcription factor FOXM1 in the malignant MC. This analysis also revealed a super enhancer near the HOXD gene cluster in this MC, which, together with general upregulation of HOX genes in the malignant MC, indicates a role of HOX genes in meningioma aggressiveness. This data elucidates the biological mechanisms rendering different epigenetic subgroups of meningiomas, and suggests leveraging HRR as a novel therapeutic target.

Fluorescence imaging of meningioma cells with somatostatin receptor ligands: an in vitro study.

BACKGROUND: The use of five-aminolevulinic acid (5-ALA) in the staining of malignant glioma cells has significantly improved intraoperative radicality in the resection of gliomas in the last decade. Currently, there is no comparable selective fluorescent substance available for meningiomas. There is however a demand for intraoperative fluorescent identification of, e.g., invasive skull base meningiomas to help improve safe radical resection. Meningiomas show high expression of the somatostatin receptor type 2, offering the possibility of receptor-targeted imaging. The authors used a somatostatin receptor-labeled fluorescence dye in the identification of meningiomas in vitro. The aim of this study was to evaluate the possibility of selective identification of meningioma cells with fluorescent techniques. METHODS: Twenty-four primary human meningioma cell cultures were analyzed. The tumor cells were incubated with FAM-TOC (5,6-Carboxyfluoresceine-Tyr3-Octreotide). As a negative control, four human dura tissues were cultured as well as a mixed cell culture in vitro and incubated with the same somatostatin receptor-labeled fluorescence substance. After incubation, fluorescence signal and intensity in all cell cultures were analyzed at three different time points using a fluorescence microscope with 488 nm epi-illumination. RESULTS: Sixteen WHO I, six WHO II, two WHO III meningioma primary cell cultures, and four dura cell cultures were analyzed. Fluorescence was detected in all meningioma cell cultures (22 cell culture stained strongly, 2 cell cultures moderately) directly after incubation up until 4 h later. There were no differences in the quality and quantity of fluorescence signal between the various meningioma grades. The fluorescence signal persisted unchanged during the analyzed period. In the negative control, dura cell cultures remained unstained. CONCLUSIONS: This study demonstrates the use of FAM-TOC in the selective fluorescent identification of meningioma cells in vitro. Further evaluation of the chemical kinetics of the applied somatostatin receptor ligand and fluorescence dye is warranted. As a next step, an experimental animal model is needed to evaluate these promising results in vivo.

miRNA-26a expression influences the therapy response to carmustine wafer implantation in patients with glioblastoma multiforme.

BACKGROUND: Glioblastoma multiforme is the most frequent malignant brain tumor in adults being marked with a very poor prognosis. Therapy concept implies concomitant radio-chemotherapy and facultative implantation of carmustine-eluted wafer. Current literature suggests microRNA 26a expression in glioblastoma to interact with alkylating chemotherapy. Subsequently, the aim of this study was to investigate the correlation of miRNA-26a expression and carmustine wafer implantation and its potential usefulness as a predictive marker for therapy response. METHODS: In total, 229 patients with glioblastoma multiforme were included into the final analysis. Of them, 80 cases were recruited from the Saarland University Medical Center for a retrospective matched-pair analysis stratified after therapy regime: One group (carmustine wafer group; n=40) received concomitant radio-chemotherapy with carmustine wafer implantation. The other group (control group; n=40) only received concomitant radio-chemotherapy. The results were confirmed by comparing them with an independent dataset of 149 patients from the TCGA database. All tumor specimens were evaluated for miRNA-26a expression, MGMT promoter methylation, and IDH1 R132H mutation status, and the results were correlated with the clinical data. RESULTS: Twenty-three patients in the carmustine wafer group showed low expression of miRNA-26a, while 17 patients showed a high expression. In the control group, 28 patients showed low expression, while 12 patients showed a high expression. The patients with high miRNA-26a expression in the carmustine wafer group were characterized by a significantly longer overall (hazard ratio [HR] 2.750 [95% CI 1.352-5.593]; p=0.004) and progression-free survival (HR 3.091 [95% CI 1.436-6.657]; p=0.003) than patients with low miRNA-26a expression. The 17 patients in the carmustine wafer group with high miRNA-26a expression showed a significantly longer progression-free survival (p=0.013) and overall survival (p=0.007) compared with the control group. There were no such correlations identified within the control group. TCGA datasets supported these findings. CONCLUSIONS: MiRNA-26a expression turned out to be a promising predictor of therapy response and clinical outcome in glioblastoma patients treated with carmustine wafer implantation. For evaluation of the role of miRNA-26a in a combined therapy setting, further studies are needed in order to translate general findings to the patient's individual situation.

Tumor antigen-specific T cells for immune monitoring of dendritic cell-treated glioblastoma patients.

BACKGROUND AIMS: CD8(+) T cells are part of the adaptive immune system and, as such, are responsible for the elimination of tumor cells. Dendritic cells (DC) are professional antigen-presenting cells (APC) that activate CD8(+) T cells. Effector CD8(+) T cells in turn mediate the active immunotherapeutic response of DC vaccination against the aggressive glioblastoma (GBM). The lack of tumor response assays complicates the assessment of treatment success in GBM patients. METHODS: A novel assay to identify specific cytotoxicity of activated T cells by APC was evaluated. Tumor antigen-pulsed DCs from HLA-A*02-positive GBM patients were cultivated to stimulate autologous cytotoxic T lymphocytes (CTL) over a 12-day culture period. To directly correlate antigen specificity and cytotoxic capacity, intracellular interferon (IFN)-γ fluorescence flow cytometry-based measurements were combined with anti-GBM tumor peptide dextramer staining. IFN-γ response was quantified by real-time polymerase chain reaction (PCR), and selected GBM genes were compared with healthy human brain cDNA by single specific primer PCR characterization. RESULTS: Using CTL of GBM patients stimulated with GBM lysate-pulsed DCs increased IFN-γ messenger RNA levels, and intracellular IFN-γ protein expression was positively correlated with specificity against GBM antigens. Moreover, the GBM peptide-specific CD8(+) T-cell response correlated with specific GBM gene expression. Following DC vaccination, GBM patients showed 10-fold higher tumor-specific signals compared with unvaccinated GBM patients. DISCUSSION: These data indicate that GBM tumor peptide-dextramer staining of CTL in combination with intracellular IFN-γ staining may be a useful tool to acquire information on whether a specific tumor antigen has the potential to induce an immune response in vivo.

Integrin-based meningioma cell migration is promoted by photon but not by carbon-ion irradiation.

PURPOSE: Sublethal doses of photon irradiation (IR) are suspected to increase tumor cell migration and support locoregional recurrence of disease, which has already been shown in other cell lines. This manuscript describes the effect of photon and carbon-ion IR on WHO class I meningioma cell migration and provides an approach to the underlying cellular mechanisms. MATERIALS AND METHODS: Meningioma cells were gained operatively at the university hospital in Homburg/Saar, Germany. For migration, membranes (8-µm pore sizes) were coated with collagen I, with collagen IV, and with fibronectin. Cells were analyzed in migration experiments with or without serum stimulation, with or without photon and carbon IR 24 h prior to experiments, and with or without integrin antibodies. Fluorescence-activated cell sorting (FACS) analyses of the integrins ανß1, ανß3, and ανß5 were performed without IR and 6, 12 and 24 h after IR. Enzyme-linked immunosorbent assay (ELISA) analyses of matrix metalloproteinases (MMP)-2 and MMP-9 were realized with and without IR after cells were cultured on collagen I, collagen IV, or fibronectin for 24 h. Cells and supernatants for FACS and ELISA were stored at - 18 °C. The significance level was set at 5 % using both Student's t test and two-way ANOVA. RESULTS: Migration of meningioma cells was serum-inducible (p < 0.001). It could be increased by photon IR (p < 0.02). The integrins ανß1 and ανß5 showed a 21 and 11 % higher expression after serum stimulation (not significant), respectively, and ανß1 expression was raised by 14 % (p = 0.0057) after photon IR. Antibody blockage of the integrins ανß1 and ανß5 inhibited serum- and photon-induced migration. Expression of MMP-2 and MMP-9 remained unchanged after both IR and fetal bovine serum (FBS). Carbon-ion IR left both integrin expression and meningioma cell migration unaffected. CONCLUSION: Photon but not carbon-ion IR promotes serum-based meningioma cell migration. Fibronectin receptor integrin ανß1 signaling can be identified as an important mechanism for serum- and photon-induced migration of WHO class I meningioma cells.

AKT1E17K mutations cluster with meningothelial and transitional meningiomas and can be detected by SFRP1 immunohistochemistry.

The activating E17K mutation in the AKT1 gene has been detected in several tumor entities. Currently several clinical studies with specific AKT1 inhibitors are under way. To determine whether AKT1 mutations are involved in human tumors of the nervous system, we examined a series of 1,437 tumors including 391 primary intracranial brain tumors and 1,046 tumors of the coverings of the central and peripheral nervous system. AKT1E17K mutations were exclusively seen in meningiomas and occurred in 65 of 958 of these tumors. A strong preponderance was seen in the variant of meningothelial meningioma WHO grade I of basal and spinal localization. In contrast, AKT1E17K mutations were rare in WHO grade II and absent in WHO grade III meningiomas. In order to more effectively detect this mutation, we tested for immunohistochemical markers associated with this alteration. We observed strong up-regulation of SFRP1 expression in all meningiomas with AKT1E17K mutation and in HEK293 cells after transfection with mutant AKT1E17K, but not in meningiomas and HEK293 cells lacking this mutation.

RB1­promoter methylation in glioblastoma: A rare event in glioblastoma.

The retinoblastoma gene (RB1) is a tumor suppressor gene that serves a key role in the development of numerous tumor diseases that can be downregulated by DNA methylation within its promoter region. The present study analyzed the methylation status of the RB1 promoter of 85 glioblastomas to assess its role in this tumor. To elucidate the underlying mechanism, RB1 promoter methylation was evaluated using methylation­specific PCR with subsequent evaluation of the results via gel electrophoresis using ethidium bromide. Of the 85 samples analyzed, only one demonstrated RB1­promoter methylation. While there are contradictory results on this matter in the literature, this study is, to the best of our knowledge, the largest on this topic to date as well as the first to use the WHO 2016 classification. The results of the present indicated that the RB1 promoter methylation does not serve a role in the development and progression of glioblastoma.

MicroRNA 200a as a histologically independent marker for meningioma recurrence: Results of a four microRNA panel analysis in meningiomas.

INTRODUCTION: Meningiomas are mostly benign neoplasms of the central nervous system. Nevertheless there are recurrences in about 20% after surgical resection. Previous studies could reveal several predictors of meningioma recurrence. Tumor progression often is associated with a specific pattern of chromosome losses. Our study investigated the potential function of selected microRNAs as markers of tumor progression. METHODS: By real-time polymerase chain reaction the expressions of microRNA 21-3p, 34a-3p, 200a-3p, and 409-3p were analyzed in solid tumor and in blood samples of 51 meningioma patients as well as in blood samples of 20 healthy individuals. Additionally, aberrations of parts of chromosomes 1, 14, 18, and 22 were analyzed by FISH. Tumor and blood samples were statistically analyzed, using Spearman's rank correlation coefficient as well as Mann-Whitney U- and Kruskal-Wallis-Test. RESULTS: MicroRNA 200a showed significantly lower expressions in recurrent meningiomas than in newly diagnosed ones. MicroRNA 409 in meningiomas was correlated significantly with tumor volume and showed a significant negative correlation with patient age. Significance was found between the expression patterns of microRNAs 34a and 200a with the respective aberrations of chromosome 1p and the microRNA 409 with aberration of chromosome 14. In the male cohort the expression of microRNA 200a in blood was significantly upregulated in patients compared to healthy volunteers. By our research the function of microRNA 200a was proved to detect meningioma patients by liquid biopsy. CONCLUSION: We detected microRNA 200a as a new biomarker to indicate meningioma recurrences. Future transferability to blood could be important for patient follow-up.

MiRNA-181d Expression Correlates in Tumor versus Plasma of Glioblastoma Patients-the Base of a Preoperative Stratification Tool for Local Carmustine Wafer Use.

OBJECTIVE: Patients with a low micro-RNA-181d (miRNA-181d) level in glioblastoma tissue benefit most of carmustine wafer use. The study compares preoperative miRNA-181d plasma and tumor expression. This may form the base to decide, from a preoperative blood test, if carmustine wafer implantation is recommendable. METHODS: A total of 60 patients suffering from glioblastoma treated between 2018 and 2020 were enrolled prospectively. Preoperatively, blood was drawn and the plasma was isolated. Tumor specimens were collected. Blood samples from 30 healthy individuals served as a reference. MiRNA-181d expression in plasma and tumor were acquired as fold change, using quantitative reverse transcription-polymerase chain reaction. Results were correlated with relevant demographic, clinical, and histopathologic aspects of the cohort. Further factors like tumor volume as well as blood panel results were considered. The Cancer Genome Atlas analysis was performed to investigate specific miRNA-181d-protein interactions to elude how miRNA-181 impact therapy response to carmustine. RESULTS: Patients with glioblastoma showed a significant overexpression of miRNA-181d compared with healthy individuals (P = 0.029). There was a significant correlation between miRNA-181d expression in tumor tissue and plasma (P = 0.001, R = 0.51). The sensitivity of low miRNA-181d expression in plasma predicting low miRNA-181d tumor expression was 76.6%. Tumor volume, preoperative medication, and items of blood panel analysis did not influence the prognostic value of plasma miRNA-181d expression. The Cancer Genome Atlas analysis revealed 8 potential protein targets to be regulated by miRNA-181d. CONCLUSION: miRNA-181d seems to be a potential molecular marker that can reliably be detected in blood samples of patients with glioblastoma. It should therefore prospectively be evaluated as a potential preoperative prognostic marker regarding carmustine wafer implantation.

Bisulfite profiling of the MGMT promoter and comparison with routine testing in glioblastoma diagnostics.

BACKGROUND: Promoter methylation of the DNA repair gene O6-methylguanine-DNA methyltransferase (MGMT) is an acknowledged predictive epigenetic marker in glioblastoma multiforme and anaplastic astrocytoma. Patients with methylated CpGs in the MGMT promoter benefit from treatment with alkylating agents, such as temozolomide, and show an improved overall survival and progression-free interval. A precise determination of MGMT promoter methylation is of importance for diagnostic decisions. We experienced that different methods show partially divergent results in a daily routine. For an integrated neuropathological diagnosis of malignant gliomas, we therefore currently apply a combination of methylation-specific PCR assays and pyrosequencing. RESULTS: To better rationalize the variation across assays, we compared these standard techniques and assays to deep bisulfite sequencing results in a cohort of 80 malignant astrocytomas. Our deep analysis covers 49 CpG sites of the expanded MGMT promoter, including exon 1, parts of intron 1 and a region upstream of the transcription start site (TSS). We observed that deep sequencing data are in general in agreement with CpG-specific pyrosequencing, while the most widely used MSP assays published by Esteller et al. (N Engl J Med 343(19):1350-1354, 2000. https://doi.org/10.1056/NEJM200011093431901 ) and Felsberg et al. (Clin Cancer Res 15(21):6683-6693, 2009. https://doi.org/10.1158/1078-0432.CCR-08-2801 ) resulted in partially discordant results in 22 tumors (27.5%). Local deep bisulfite sequencing (LDBS) revealed that CpGs located in exon 1 are suited best to discriminate methylated from unmethylated samples. Based on LDBS data, we propose an optimized MSP primer pair with 83% and 85% concordance to pyrosequencing and LDBS data. A hitherto neglected region upstream of the TSS, with an overall higher methylation compared to exon 1 and intron 1 of MGMT, is also able to discriminate the methylation status. CONCLUSION: Our integrated analysis allows to evaluate and redefine co-methylation domains within the MGMT promoter and to rationalize the practical impact on assays used in daily routine diagnostics.

CK2 Activity Mediates the Aggressive Molecular Signature of Glioblastoma Multiforme by Inducing Nerve/Glial Antigen (NG)2 Expression.

Nerve/glial antigen (NG)2 expression crucially determines the aggressiveness of glioblastoma multiforme (GBM). Recent evidence suggests that protein kinase CK2 regulates NG2 expression. Therefore, we investigated in the present study whether CK2 inhibition suppresses proliferation and migration of NG2-positive GBM cells. For this purpose, CK2 activity was suppressed in the NG2-positive cell lines A1207 and U87 by the pharmacological inhibitor CX-4945 and CRISPR/Cas9-mediated knockout of CK2α. As shown by quantitative real-time PCR, luciferase-reporter assays, flow cytometry and western blot, this significantly reduced NG2 gene and protein expression when compared to vehicle-treated and wild type controls. In addition, CK2 inhibition markedly reduced NG2-dependent A1207 and U87 cell proliferation and migration. The Cancer Genome Atlas (TCGA)-based data further revealed not only a high expression of both NG2 and CK2 in GBM but also a positive correlation between the mRNA expression of the two proteins. Finally, we verified a decreased NG2 expression after CX-4945 treatment in patient-derived GBM cells. These findings indicate that the inhibition of CK2 represents a promising approach to suppress the aggressive molecular signature of NG2-positive GBM cells. Therefore, CX-4945 may be a suitable drug for the future treatment of NG2-positive GBM.

A different view on DNA amplifications indicates frequent, highly complex, and stable amplicons on 12q13-21 in glioma.

To further understand the biological significance of amplifications for glioma development and recurrencies, we characterized amplicon frequency and size in low-grade glioma and amplicon stability in vivo in recurring glioblastoma. We developed a 12q13-21 amplicon-specific genomic microarray and a bioinformatics amplification prediction tool to analyze amplicon frequency, size, and maintenance in 40 glioma samples including 16 glioblastoma, 10 anaplastic astrocytoma, 7 astrocytoma WHO grade 2, and 7 pilocytic astrocytoma. Whereas previous studies reported two amplified subregions, we found a more complex situation with many amplified subregions. Analyzing 40 glioma, we found that all analyzed glioblastoma and the majority of pilocytic astrocytoma, grade 2 astrocytoma, and anaplastic astrocytoma showed at least one amplified subregion, indicating a much higher amplification frequency than previously suggested. Amplifications in low-grade glioma were smaller in size and displayed clearly different distribution patterns than amplifications in glioblastoma. One glioblastoma and its recurrencies revealed an amplified subregion of 5 Mb that was stable for 6 years. Expression analysis of the amplified region revealed 10 overexpressed genes (i.e., KUB3, CTDSP2, CDK4, OS-9, DCTN2, RAB3IP, FRS2, GAS41, MDM2, and RAP1B) that were consistently overexpressed in all cases that carried this amplification. Our data indicate that amplifications on 12q13-21 (a) are more frequent than previously thought and present in low-grade tumors and (b) are maintained as extended regions over long periods of time.

p15 promoter methylation - a novel prognostic marker in glioblastoma patients.

Glioblastomas are the most frequent and malignant brain tumors in adults. Surgical cure is virtually impossible and despite radiation and chemotherapy the clinical course is very poor. Epigenetic silencing of MGMT has been associated with a better response to temozolomide-chemotherapy. We previously showed that temozolomide increases the median survival time of patients with tumors harbouring deletions on 9p within the region for p15(INK4b), p16(INK4a), and 10q (MGMT). The aim of this study was to investigate the methylation status of p15, p16, p14ARF and MGMT in glioblastomas (n=27) and to correlate the results with the clinical data. Only patients with KPS >70, radical tumor resection, radiation and temozolomide-chemotherapy after recurrence were included. We observed promoter methylation of MGMT in 56% and of p15 in 37% of the tumors, whereas methylation of p16 and p14ARF were rare. Interestingly, methylation of p15 emerged as a significant predictor of shorter overall survival (16.9 vs. 23.8 months, p=0.025), whereas MGMT promoter methylation had no significant effect on median overall survival under this treatment regimen (22.5 vs. 22.1 months, p=0.49). In the presence of other clinically relevant factors, p15 methylation remains the only significant predictor (p=0.021). Although these results need to be confirmed in larger series as well as under different treatment conditions, our retrospective study shows clear evidence that p15 methylation is an important prognostic factor for survival and underlines that this tumor suppressor, involved in cell cycle control, is an attractive candidate for therapeutic approaches in glioblastomas.

Deletions in the 17q chromosomal region and their influence on the clonal cytogenetic evolution of recurrent meningiomas.

OBJECTIVE: Meningiomas are among the most frequent intracranial tumors. Although the majority of meningiomas can be cured by surgical resection, up to 20% of the patients develop an aggressive clinical course with tumor recurrence or progressive disease.Cytogenetically, meningiomas frequently harbour a normal karyotype or monosomy of chromosome 22 as the sole anomaly. However, progression of meningiomas is associated with a non-random pattern of secondary losses of the chromosomes and chromosomal regions 1p, 6, 10, 14, 18, and 19. There is evidence, that loss of chromosome 17 might be involved in the clonal cytogenetic evolution of recurrent meningiomas. The aim of this study was to determine the role of deletions in the 17q chromosomal region in patients with recurrent meningiomas. RESULTS: The authors retrospectively reviewed all patients that underwent repeated surgery for recurrent meningiomas between 1999 and 2015 at the Department of Neurosurgery of the Saarland University Hospital. Patients were included in this study if tumor samples from two or more different meningiomas were available.A total of 7 patients underwent repeated surgery for recurrent meningiomas (4 males, 3 females, mean age: 45.4 years at the date of surgery) between 1999 and 2015. Collectively, 22 biopsies were analyzed with FISH (fluorescence-in-situ-hybridization) for the chromosomal region 17q23.3. In 20/22 (90.1%) specimens, the tumor samples harboured a significant deletion in the chromosomal region 17q (range: 10 to 63% of the cells). In 3/3 (100%) cases, deletion in the 17q chromosomal region was detectable in the primary tumor. In the tumor evolution, there was no steady in- or decrease in the percentage of this deletion. CONCLUSION: Deletion in the 17q chromosomal region was present in the patients' primary tumors as well as in late recurrences. Overall, a significant deletion in the 17q chromosomal region was detected in 90.1% of the tumors. Thus, the authors assume that deletion in the 17q chromosomal region displays rather an early event in meningioma progression. Accordingly, deletion in the 17q chromosomal region might clinically serve as a potential early marker for malignancy and a higher risk for recurrence in meningiomas.

MiRNA-181d Expression Significantly Affects Treatment Responses to Carmustine Wafer Implantation.

BACKGROUND: Standard therapeutic protocols for glioblastoma, the most aggressive type of brain cancer, include surgery followed by chemoradiotherapy. Additionally, carmustine-eluting wafers can be implanted locally into the resection cavity. OBJECTIVE: To evaluate microRNA (miRNA)-181d as a prognostic marker of responses to carmustine wafer implantation. METHODS: A total of 80 glioblastoma patients (40/group) were included in a matched pair analysis. One group (carmustine wafer group) received concomitant chemoradiotherapy with carmustine wafer implantation (Stupp protocol). The second group (control group) received only concomitant chemoradiotherapy. All tumor specimens were subjected to evaluations of miRNA-181d expression, results were correlated with further individual clinical data. The Cancer Genome Atlas (TCGA) dataset of 149 patients was used as an independent cohort to validate the results. RESULTS: Patients in the carmustine wafer group with low miRNA-181d expression had significantly longer overall (hazard ratio [HR], 35.03, [95% confidence interval (CI): 3.50-350.23], P = .002) and progression-free survival (HR, 20.23, [95% CI: 2.19-186.86], P = .008) than patients of the same group with a high miRNA-181d expression. These correlations were not observed in the control group. The nonsignificance in the control group was confirmed in the independent TCGA dataset. The carmustine wafer group patients with low miRNA-181d expression also had a significantly longer progression-free (P = .049) and overall survival (OS) (P = .034), compared with control group patients. Gross total resection correlated significantly with longer OS (P = .023). CONCLUSION: MiRNA-181d expression significantly affects treatment responses to carmustine wafer implantation.

Incidence, mortality and outcome of meningiomas: A population-based study from Germany.

BACKGROUND: Meningiomas are mostly benign tumors that originate from the coverings of the brain and spinal cord. Compared to malignant glial tumors, meningiomas are relatively understudied with regard to their risk factors and epidemiology. In particular, population-based data on cancer burden and patient outcomes are scant. METHODS: Population-based data from Saarland, a federal state in South-Western Germany, were used; the data included 992 patients diagnosed with a first meningioma between 2000 and 2015. Incidence and mortality rates-as well as estimates of observed and relative survival and cumulative incidence of tumor recurrence up to 10 years after diagnosis-were derived by sex, age, WHO grade, and whether or not the patient had undergone surgery. RESULTS: This population-based study not only included patients treated in the regional university hospital but also those treated elsewhere or patients without any surgical treatment. The mean age of the patients at diagnosis was 63 years, and 70%, 28% and 3% had WHO grade I, II and III meningiomas, respectively. Ten-year observed and relative survival of all patients combined was 72% and 91% respectively. Tumor-related mortality varied by sex and increased with age at diagnosis and the WHO grade of the tumor. The overall 10-year cumulative incidence of meningioma recurrence was 9%. CONCLUSION: This analysis represents the first modern population-based analysis of meningioma incidence and mortality and outcomes of patients with such neoplasms in Germany. Derived from an unselected sample of patients, this study may fill a hitherto existing gap in the literature on meningiomas.

The Influence of Distinct Regulatory miRNAs of the p15/p16/RB1/E2F Pathway on the Clinical Progression of Glioblastoma Multiforme.

OBJECTIVE: The microRNAs (miRNAs) -26a, -24, and -21 have been reported as regulators of the P15/P16/RB1/E2F pathway, which plays a major role in glioblastoma multiforme (GBM) progression. In the present study, their predictive marker for the progression of GBMs is evaluated and described. METHODS: The expression of miRNA-21, -24, and -26a was analyzed as fold change (FC) in tumor specimens of 104 patients with GBM and 8 specimen of non-neoplastic brain tissue as control group. The results were referred to the individual clinical data sets and evaluated statistically. RESULTS: The FC of miRNA-21, -24, and -26a was 1.51 ± 1.35, 0.75 ± 0.67, and 0.39 ± 0.24 in the tumor samples. Within the control group, FC of miRNA-21, -24, and -26a was 0.31 ± 0.51, 0.66 ± 0.33, and 0.18 ± 0.11, respectively. MiRNA-26a and -21 were significantly overexpressed in GBM samples compared with healthy brain tissue (miRNA-21: P < 0.001; miRNA-26a: P = 0.011). High expression ofmiRNA-24 trended for a prolonged overall survival (P = 0.07). Patients with high miRNA-26a expression showed a significantly prolonged progression-free survival (hazard ratio 0.21; 95% confidence interval 0.09-0.51], P < 0.001) and overall survival (hazard ratio 0.3; 95% confidence interval 0.136-0.682], P = 0.003). The effect of miRNA-26a was mediated via regulation of mRNA of RB1. There was a significant inverse correlation between mRNA-26a and mRNA expression of RB1. CONCLUSIONS: The expression levels of miRNA-26a and -24 turned out to be promising predictors of further clinical course in patients with GBM multiforme.