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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.

Meningiomas are tumors that arise from the coverings of the brain or spinal cord. 5% of the cases turn into malignant forms with aggressive clinical behavior and increased risk of tumor recurrence. One hundred and five patients with meningiomas were operated by open surgery. To investigate predictors of meningioma recurrence in total 124 samples of 105 patients were investigated by iFISH. Dual-probe hybridization was performed to access chromosomal alterations of chromosomes 1p-, 9p- and 22q. Additionally, methylation of TIMP3 and p16 was analyzed with MS-PCR. Of the 105 investigated tumors 59.1% (62/105) were WHO grade I, 33.3% (35/105) were WHO grade II and 7.7% (8/105) were anaplastic meningiomas (grade III), respectively. The histopathological data correlates with the recurrence rate of the investigated meningiomas. Hypermethylation of TIMP3 was detected in 13.3% of all meningiomas: 10.9% in WHO grade I meningiomas, 25.0% in grade II and 14.3% in grade III meningiomas, respectively. No correlation of TIMP3 hypermethylation with tumor recurrence or WHO grade (p = 0.2) was observed. Interestingly, deletion of 1p36 emerged as a significant predictor of shorter overall survival (log rank test, p<0.001), whereas TIMP3 promoter methylation had no significant effect on overall survival (log rank test, p = 0.799). The results of the current study support the finding that the deletion of chromosome 1p is an independent marker of meningioma recurrence and progression (p = 0.0097). Therefore the measurement of genetic aberrations in meningiomas allows in a combined histological approach a more precise assessment of the prognosis of meningiomas than histopathology alone.

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.

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. Workflow process: Comparison of expression levels of microRNAs with chromosomal aberrations and clinical data.

•We analysed more than 1500 meningioma patients with a follow up as far as 38 yrs.•Main result is the better progression free survival nowadays.•The prognosis of meningiomas could be improved by the introduction of imaging.•Perioperative mortality rate has been reduced since the 1970s.•Detection of meningioma WHO grade II has been increased significantly today. The benefit of the current strategy of diagnosis and treatment of meningiomas in contrast to the standard treatment in use before computer tomographic and magnetic resonance imaging and before the microsurgical era has not yet been determined. Two groups of patients were compared, those on which surgery was performed before the year of 1985, when computer tomographic (CT) imaging was not yet available in our clinic and those who were treated after at the Neurosurgical Department of Saarland University. Average follow-up time was 17.9±9.3years for group 1 and 9.2±4.3years for group 2. The number of patients with advanced age who had surgical treatment was significantly increased in the second group, whereas the number of perioperative complications found was nearly equal in both groups (17.8% vs. 18.8%). Nevertheless, perioperative morbidity was reduced from 2.2% to 1.2%. The postoperative recurrence free time period could be revealed to be longer in the first collective (p<0.0001). Furthermore, this study shows a notable increase of the incidence of WHO grade II meningiomas in patients treated after 1985. Based on the presented results, the overall prognosis for patients with meningiomas has changed from the 1960s until today, since over the last two decades there has been a prolonged progression free survival time in addition to a reduced perioperative mortality rate. In the postoperative management of these patients genetic aberrations and microbiological markers should be considered as prognostic factors for meningiomas in addition to histopathological grading.

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.

Background To assess the influence of molecular markers with potential prognostic value to groups of patients with newly diagnosed glioblastoma patients were examined: group A with 36 patients (surgical resection plus standard combined chemoradiotherapy) and group B with 36 patients (surgical resection, standard combined chemoradiotherapy plus carmustine wafer implantation). Our aim was to determine chromosomal alterations, methylation status of MGMT, p15, and p16 (CDKN2A) in order to analyse the influence on patient survival time as well as radio- and chemotherapy responses. Promoter hypermethylation of MGMT, p16, and p15 genes were determined by MS-PCR. Comparative genomic hybridisation (CGH) analyses were performed with isolated, labelled DNA of each tumor to detect genetic alterations. Results Age of onset of the disease showed a significant effect on overall survival (OS) ( p  < 0.0001). Additional treatment with carmustine wafer (group B) compared to the control group (group A) did not result in improved OS ( p  = 0.562). Patients with a methylated MGMT promotor showed a significant longer OS compared to those patients with unmethylated MGMT promotor ( p  = 0.041). Subgroup analyses revealed that patients with methylated p15 showed a significant shorter OS when administered to group B rather than in group A ( p  = 0.0332). In patients additionally treated with carmustine wafer an amplification of 4q12 showed a significant impact on a reduced OS ( p  = 0.00835). In group B, a loss of 13q was significantly associated with a longer OS ( p  = 0.0364). If a loss of chromosome 10 occurred, patients in group B showed a significantly longer OS ( p  = 0.0123). Conclusion A clinical benefit for the widespread use of additional carmustine wafer implantation could not be found. However, carmustine wafer implantation shows a significantly improved overall survival if parts of chromosome 10 or chromosome 13 are deleted. In cases of 4q12 amplification and in cases of a methylated p15 promotor, the use of carmustine wafers is especially not recommended. The MGMT promoter methylation is a strong prognostic Biomarker for benefit from temozolomide and BCNU chemotherapy.

•First population-based analysis of meningioma from Germany.•Incidence and mortality and outcomes of patients with meningiomas.•Unselected samples of patients with meningiomas. 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. 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. 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%. 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.

BackgroundThe 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.MethodsTwenty-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.ResultsSixteen 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.ConclusionsThis 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.

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 methylation-specific PCR with subsequent evaluation of the results via gel electrophoresis using ethidium bromide. Of the 85 samples analyzed, only one demonstrated RB1-promoter 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.