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1.
J Neurooncol ; 161(3): 563-572, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36719614

RESUMEN

PURPOSE: To assess the impact of individual surgeon experience on overall survival (OS), extent of resection (EOR) and surgery-related morbidity in elderly patients with glioblastoma (GBM), we performed a retrospective case-by-case analysis. METHODS: GBM patients aged ≥ 65 years who underwent tumor resection at two academic centers were analyzed. The experience of each neurosurgeon was quantified in three ways: (1) total number of previously performed glioma surgeries (lifetime experience); (2) number of surgeries performed in the previous five years (medium-term experience) and (3) in the last two years (short-term experience). Surgeon experience data was correlated with survival (OS) and surrogate parameters for surgical quality (EOR, morbidity). RESULTS: 198 GBM patients (median age 73.0 years, median preoperative KPS 80, IDH-wildtype status 96.5%) were included. Median OS was 10.0 months (95% CI 8.0-12.0); median EOR was 89.4%. Surgery-related morbidity affected 19.7% patients. No correlations of lifetime surgeon experience with OS (P = .693), EOR (P = .693), and surgery-related morbidity (P = .435) were identified. Adjuvant therapy was associated with improved OS (P < .001); patients with surgery-related morbidity were less likely to receive adjuvant treatment (P = .002). In multivariable testing, adjuvant therapy (P < .001; HR = 0.064, 95%CI 0.028-0.144) remained the only significant predictor for improved OS. CONCLUSION: Less experienced neurosurgeons achieve similar surgical results and outcome in elderly GBM patients within the setting of academic teaching hospitals. Adjuvant treatment and avoidance of surgery-related morbidity are crucial for generating a treatment benefit for this cohort.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Anciano , Humanos , Glioblastoma/patología , Estudios Retrospectivos , Neoplasias Encefálicas/patología , Procedimientos Neuroquirúrgicos/métodos , Neurocirujanos , Hospitales de Enseñanza
2.
Neuropathol Appl Neurobiol ; 48(3): e12773, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34799864

RESUMEN

TERT promoter mutations have been associated with increased risk of recurrence in meningioma cohorts, thus a potential biomarker for aggressive phenotypes. A main purpose of refining tumour classification is better predictions on the patient level. We compiled data from previous published cohorts to investigate patient-level predictions of recurrence based on TERTp-mut status. Implementation of TERTp-mut into the WHO grading led to better patient prognostication by improved prediction of recurrence. Our results support implementation of TERTp-mut into diagnostics and classification of meningiomas.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Telomerasa , Humanos , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Meningioma/genética , Meningioma/patología , Mutación , Regiones Promotoras Genéticas/genética , Telomerasa/genética , Organización Mundial de la Salud
3.
Acta Neuropathol ; 142(2): 339-360, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34046693

RESUMEN

Ependymomas (EPN) are central nervous system tumors comprising both aggressive and more benign molecular subtypes. However, therapy of the high-risk subtypes posterior fossa group A (PF-A) and supratentorial RELA-fusion positive (ST-RELA) is limited to gross total resection and radiotherapy, as effective systemic treatment concepts are still lacking. We have recently described fibroblast growth factor receptors 1 and 3 (FGFR1/FGFR3) as oncogenic drivers of EPN. However, the underlying molecular mechanisms and their potential as therapeutic targets have not yet been investigated in detail. Making use of transcriptomic data across 467 EPN tissues, we found that FGFR1 and FGFR3 were both widely expressed across all molecular groups. FGFR3 mRNA levels were enriched in ST-RELA showing the highest expression among EPN as well as other brain tumors. We further identified high expression levels of fibroblast growth factor 1 and 2 (FGF1, FGF2) across all EPN subtypes while FGF9 was elevated in ST-EPN. Interrogation of our EPN single-cell RNA-sequencing data revealed that FGFR3 was further enriched in cycling and progenitor-like cell populations. Corroboratively, we found FGFR3 to be predominantly expressed in radial glia cells in both mouse embryonal and human brain datasets. Moreover, we detected alternative splicing of the FGFR1/3-IIIc variant, which is known to enhance ligand affinity and FGFR signaling. Dominant-negative interruption of FGFR1/3 activation in PF-A and ST-RELA cell models demonstrated inhibition of key oncogenic pathways leading to reduced cell growth and stem cell characteristics. To explore the feasibility of therapeutically targeting FGFR, we tested a panel of FGFR inhibitors in 12 patient-derived EPN cell models revealing sensitivity in the low-micromolar to nano-molar range. Finally, we gain the first clinical evidence for the activity of the FGFR inhibitor nintedanib in the treatment of a patient with recurrent ST-RELA. Together, these preclinical and clinical data suggest FGFR inhibition as a novel and feasible approach to combat aggressive EPN.


Asunto(s)
Ependimoma/patología , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Animales , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/patología , Ependimoma/genética , Humanos , Ratones , Recurrencia Local de Neoplasia/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptores de Factores de Crecimiento de Fibroblastos/genética
4.
Int J Mol Sci ; 22(22)2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-34830407

RESUMEN

Due to its cost-efficiency, high resolution melting (HRM) analysis plays an important role in genotyping of candidate single nucleotide polymorphisms (SNPs). Studies indicate that HRM analysis is not only suitable for genotyping individual SNPs, but also allows genotyping of multiple SNPs in one and the same amplicon, although with limited discrimination power. By targeting the three C>T SNPs rs527559815, rs547832288, and rs16906252, located in the promoter of the O6-methylguanine-DNA methyltransferase (MGMT) gene within a distance of 45 bp, we investigated whether the discrimination power can be increased by coupling HRM analysis with pyrosequencing (PSQ). After optimizing polymerase chain reaction (PCR) conditions, PCR products subjected to HRM analysis could directly be used for PSQ. By analyzing oligodeoxynucleotide controls, representing the 36 theoretically possible variant combinations for diploid human cells (8 triple-homozygous, 12 double-homozygous, 12 double-heterozygous and 4 triple-heterozygous combinations), 34 out of the 36 variant combinations could be genotyped unambiguously by combined analysis of HRM and PSQ data, compared to 22 variant combinations by HRM analysis and 16 variant combinations by PSQ. Our approach was successfully applied to genotype stable cell lines of different origin, primary human tumor cell lines from glioma patients, and breast tissue samples.


Asunto(s)
Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Glioma/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Regiones Promotoras Genéticas/genética , Proteínas Supresoras de Tumor/genética , Mama/metabolismo , Mama/patología , Metilación de ADN/genética , Femenino , Congelación , Genotipo , Glioma/metabolismo , Glioma/patología , Humanos , Polimorfismo de Nucleótido Simple/genética
5.
Br J Cancer ; 122(10): 1441-1444, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32203223

RESUMEN

Elevated levels of serum ferritin (SF) are observed in several types of cancer; however, little is known on the association between ferritin and glioma, the most frequent type of human primary brain tumour. Here we report that GBM patients show significantly increased pre-surgical SF levels (i.e. ferritinaemia) within the SF reference range and a marked ferritin immunoreactivity of resected tumour tissue. Our findings account for an indirect association between ferritin synthesis in glioma-tissue and altered SF levels, which limits the clinical value of SF as a tumour marker in glioma. Importantly, we show for the first time that GBM-derived glioma cells release ferritin in vitro, which exerts an apoptosis-stimulating activity. Albeit the pathophysiologic context of apoptosis induction by a tumour-derived ferritin remains to be defined, our findings account for a distinct growth-regulatory role of these ferritin species in tumour biology.


Asunto(s)
Biomarcadores de Tumor/sangre , Ferritinas/sangre , Glioblastoma/sangre , Glioma/sangre , Apoptosis/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Proliferación Celular/genética , Femenino , Ferritinas/genética , Regulación Neoplásica de la Expresión Génica/genética , Glioblastoma/genética , Glioblastoma/patología , Glioma/genética , Glioma/patología , Humanos , Masculino , Adhesión en Parafina , Transducción de Señal/genética
6.
J Neurol Neurosurg Psychiatry ; 91(4): 378-387, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32041819

RESUMEN

BACKGROUND: TERT gene alterations (TERT-alt) have been linked to increased risk of recurrence in meningiomas, whereas the association to mortality largely remain incompletely investigated. As incongruence between clinical course and WHO grade exists, reliable biomarkers have been sought. METHODS: We applied the Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data Statement. We compiled data from eight studies and allocated patients to TERT-alt (n=59) or TERT promoter wild-type (TERTp-wt; n=618). We compared the two groups stratified for WHO grades as: incidence rates, survival probabilities and cumulative recurrences. We estimated the effects of WHO grade, age at diagnosis and sex as HRs. RESULTS: TERT-alt occurred in 4.7%, 7.9% and 15.4% of WHO-I/WHO-II/WHO-III meningiomas, respectively. The median recurrence-free survival was 14 months for all TERT-alt patients versus 101 months for all TERTp-wt patients. The HR for TERT-alt was 3.74 in reference to TERTp-wt. For all TERT-alt patients versus all TERTp-wt patients, the median overall survival was 58 months and 160 months, respectively. The HR for TERT-alt was 2.77 compared with TERTp-wt. TERT-alt affected prognosis independent of WHO grades. Particularly, the recurrence rate was 4.8 times higher in WHO-I/-II TERT-alt patients compared with WHO-III TERTp-wt patients. The mortality rate was 2.7 times higher in the WHO-I and WHO-II TERT-alt patients compared with WHO-III TERTp-wt patients. CONCLUSIONS: TERT-alt is an important biomarker for significantly higher risk of recurrence and death in meningiomas. TERT-alt should be managed and surveilled aggressively. We propose that TERT-alt analysis should be implemented as a routine diagnostic test in meningioma and integrated into the WHO classification. TRIAL REGISTRATION NUMBER: PROSPERO: CRD42018110566.


Asunto(s)
Neoplasias Meníngeas/genética , Meningioma/genética , Telomerasa/genética , Humanos , Neoplasias Meníngeas/mortalidad , Neoplasias Meníngeas/patología , Meningioma/mortalidad , Meningioma/patología , Mutación , Pronóstico , Regiones Promotoras Genéticas , Tasa de Supervivencia , Organización Mundial de la Salud
7.
J Cell Mol Med ; 23(1): 281-292, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30467961

RESUMEN

Glioblastoma is the most dangerous brain cancer. One reason for glioblastoma's aggressiveness are glioblastoma stem-like cells. To target them, a number of markers have been proposed (CD133, CD44, CD15, A2B5, CD36, CXCR4, IL6R, L1CAM, and ITGA6). A comprehensive study of co-expression patterns of them has, however, not been performed so far. Here, we mapped the multidimensional co-expression profile of these stemness-associated molecules. Gliomaspheres - an established model of glioblastoma stem-like cells - were used. Seven different gliomasphere systems were subjected to multicolor flow cytometry measuring the nine markers CD133, CD44, CD15, A2B5, CD36, CXCR4, IL6R, L1CAM, and ITGA6 all simultaneously based on a novel 9-marker multicolor panel developed for this study. The viSNE dimensionality reduction algorithm was applied for analysis. All gliomaspheres were found to express at least five different glioblastoma stem-like cell markers. Multi-dimensional analysis showed that all studied gliomaspheres consistently harbored a cell population positive for the molecular signature CD44+/CD133+/ITGA6+/CD36+. Glioblastoma patients with an enrichment of this combination had a significantly worse survival outcome when analyzing the two largest available The Cancer Genome Atlas datasets (MIT/Harvard Affymetrix: P = 0.0015, University of North Carolina Agilent: P = 0.0322). In sum, we detected a previously unknown marker combination - demonstrating feasibility, usefulness, and importance of high-dimensional gliomasphere marker combinatorics.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/patología , Citometría de Flujo/métodos , Glioblastoma/patología , Antígeno AC133/análisis , Algoritmos , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Antígenos CD36/análisis , Adhesión Celular/fisiología , Línea Celular Tumoral , Simulación por Computador , Glioblastoma/metabolismo , Glioblastoma/mortalidad , Humanos , Receptores de Hialuranos/análisis , Integrina alfa6/análisis , Estimación de Kaplan-Meier , Células Madre Neoplásicas/metabolismo
8.
Cytotherapy ; 21(6): 643-658, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30975602

RESUMEN

BACKGROUND: Glioblastoma is the most aggressive type of brain cancer. Dendritic cell (DC)-based immunotherapy against glioblastoma depends on the effectiveness of loaded antigens. Sphere-inducing culture conditions are being studied by many as a potential antigen source. Here, we investigated two different in vitro conditions (spheroid culture versus adherent culture) in relation to DC immunotherapy: (1) We studied the specific spheroid-culture proteome and assessed the clinical importance of spheroid proteins. (2) We evaluated the immunogenicity of spheroid lysate - both compared to adherent conditions. METHODS: We used seven spheroid culture systems, three of them patient-derived. Stemness-related markers were studied in those three via immunofluorescence. Spheroid-specific protein expression was measured via quantitative proteomics. The Cancer Genome Atlas (TCGA) survival data was used to investigate the clinical impact of spheroid proteins. Immunogenicity of spheroid versus adherent cell lysate was explored in autologous ELISPOT systems (DCs and T cells from the three patients). RESULTS: (1) The differential proteome of spheroid versus adherent glioblastoma culture conditions could successfully be established. The top 10 identified spheroid-specific proteins were associated with significantly decreased overall survival (TCGA MIT/Harvard cohort; n = 350, P = 0.014). (2) In exploratory experiments, immunogenicity of spheroid lysate vis-á-vis interferon (IFN)γ production was lower than that of adherent cell lysate (IFNγ ELISPOT; P = 0.034). CONCLUSIONS: Spheroid culture proteins seem to represent survival-relevant targets, supporting the use of spheroid culture conditions as an antigen source for DC immunotherapy. However, immunogenicity enhancement should be considered for future research. Transferability of our findings in terms of clinical impact and regarding different spheroid-generation techniques needs further validation.


Asunto(s)
Neoplasias Encefálicas/inmunología , Técnicas de Cultivo de Célula/métodos , Células Dendríticas/inmunología , Glioblastoma/inmunología , Proteínas de Neoplasias/inmunología , Antígenos de Neoplasias/inmunología , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/patología , Glioblastoma/patología , Humanos , Inmunoterapia/métodos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Proteínas de Neoplasias/metabolismo , Esferoides Celulares/patología , Linfocitos T/inmunología , Células Tumorales Cultivadas
10.
Cells ; 12(12)2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37371109

RESUMEN

The repair protein O6-methylguanine-DNA methyltransferase (MGMT) is regulated epigenetically, mainly by the methylation of the MGMT promoter. MGMT promoter methylation status has emerged as a prognostic and predictive biomarker for patients with newly diagnosed glioblastoma (GBM). However, a strong negative correlation between MGMT promoter methylation and MGMT protein expression cannot be applied as a rule for all GBM patients. In order to investigate if the DNA methylation status of MGMT enhancers is associated with MGMT promoter methylation, MGMT expression, and the overall survival (OS) of GBM patients, we established assays based on high-resolution melting analysis and pyrosequencing for one intragenic and three intergenic MGMT enhancers. For CpGs in an enhancer located 560 kb upstream of the MGMT promoter, we found a significant negative correlation between the methylation status and MGMT protein levels of GBM samples expressing MGMT. The methylation status of CpGs in the intragenic enhancer (hs696) was strongly negatively correlated with MGMT promoter methylation and was significantly higher in MGMT-expressing GBM samples than in MGMT-non-expressing GBM samples. Moreover, low methylation of CpGs 01-03 and CpGs 09-13 was associated with the longer OS of the GBM patients. Our findings indicate an association between MGMT enhancer methylation and MGMT promoter methylation, MGMT protein expression, and/or OS.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Neoplasias Encefálicas/metabolismo , Metilación de ADN/genética , Metilasas de Modificación del ADN/genética , Metilasas de Modificación del ADN/metabolismo , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Glioblastoma/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
11.
Cancers (Basel) ; 15(24)2023 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-38136323

RESUMEN

The response of glioblastoma (GBM) patients to the alkylating agent temozolomide (TMZ) vitally depends on the expression level of the repair protein O6-methylguanine-DNA methyltransferase (MGMT). Since MGMT is strongly regulated by promoter methylation, the methylation status of the MGMT promoter has emerged as a prognostic and predictive biomarker for GBM patients. By determining the methylation levels of the four enhancers located within or close to the MGMT gene, we recently found that enhancer methylation contributes to MGMT regulation. In this study, we investigated if methylation of the four enhancers is associated with SNP rs16906252, TERT promoter mutations C228T and C250T, TERT SNP rs2853669, proliferation index Ki-67, overall survival (OS), age, and sex of the patients. In general, associations with genetic variants, clinical parameters, and demographic characteristics were caused by a complex interplay of multiple CpGs in the MGMT promoter and of multiple CpGs in enhancer regions. The observed associations for intragenic enhancer 4, located in intron 2 of MGMT, differed from associations observed for the three intergenic enhancers. Some findings were restricted to subgroups of samples with either methylated or unmethylated MGMT promoters, underpinning the relevance of the MGMT promoter status in GBMs.

12.
EMBO Mol Med ; 15(3): e16959, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36740985

RESUMEN

The natural compound Artemisinin is the most widely used antimalarial drug worldwide. Based on its cytotoxicity, it is also used for anticancer therapy. Artemisinin and its derivates are endoperoxides that damage proteins in eukaryotic cells; their definite mechanism of action and host cell targets, however, have remained largely elusive. Using yeast and haploid stem cell screening, we demonstrate that a single cellular pathway, namely porphyrin (heme) biosynthesis, is required for the cytotoxicity of Artemisinins. Genetic or pharmacological modulation of porphyrin production is sufficient to alter its cytotoxicity in eukaryotic cells. Using multiple model systems of human brain tumor development, such as cerebral glioblastoma organoids, and patient-derived tumor spheroids, we sensitize cancer cells to dihydroartemisinin using the clinically approved porphyrin enhancer and surgical fluorescence marker 5-aminolevulinic acid, 5-ALA. A combination treatment of Artemisinins and 5-ALA markedly and specifically killed brain tumor cells in all model systems tested, including orthotopic patient-derived xenografts in vivo. These data uncover the critical molecular pathway for Artemisinin cytotoxicity and a sensitization strategy to treat different brain tumors, including drug-resistant human glioblastomas.


Asunto(s)
Antimaláricos , Artemisininas , Neoplasias Encefálicas , Humanos , Artemisininas/farmacología , Artemisininas/uso terapéutico , Antimaláricos/farmacología , Hemo/metabolismo , Ácido Aminolevulínico , Neoplasias Encefálicas/tratamiento farmacológico
13.
Cancer ; 118(20): 5038-49, 2012 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-22392434

RESUMEN

BACKGROUND: Meningiomas are common intracranial tumors arising from the meninges and usually are benign. However, a few meningiomas have aggressive behavior and, for such patients, effective treatment options are needed. Trabectedin is a novel, marine-derived, antineoplastic agent that has been approved and is used routinely as therapy for advanced soft tissue sarcoma and ovarian cancer. METHODS: The authors investigated the in vitro effects of trabectedin alone and in combination with hydroxyurea, cisplatin, and doxorubicin in primary cell cultures of benign (n = 9), atypical (n = 6), and anaplastic (n = 4) meningiomas using chemosensitivity assays (3-[4,5dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide [MTT]), Western blot analysis, cell cycle analysis, and immunofluorescent staining. RESULTS: Strong antimeningioma activity of trabectedin was observed and was characterized by distinct cell cycle arrest, down-regulation of multiple cyclins, deregulated expression of cell death-regulatory genes, and massive apoptosis induction. Cytotoxic activity was especially intense in higher grade meningiomas with a half-maximal inhibitory concentration <10 nM. Combination with trabectedin synergistically enhanced the antimeningioma activity of hydroxyurea but also enhanced the activity of doxorubicin and cisplatin. On the basis of these findings, trabectedin was given to 1 patient who had heavily pretreated, anaplastic meningioma, and a favorable response was observed with radiologic disease stabilization, marked reductions in brain edema and requirement for corticosteroids, and improvement of clinical symptoms. However, treatment had to be discontinued after 5 cycles because of adverse drug effects. CONCLUSIONS: The current results indicated that trabectedin may represent a promising new therapeutic option for patients with aggressive meningioma and should be evaluated in prospective clinical studies.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Dioxoles/uso terapéutico , Neoplasias Meníngeas/tratamiento farmacológico , Meningioma/tratamiento farmacológico , Tetrahidroisoquinolinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis , Dioxoles/administración & dosificación , Evaluación Preclínica de Medicamentos , Humanos , Masculino , Neoplasias Meníngeas/patología , Meningioma/patología , Persona de Mediana Edad , Tetrahidroisoquinolinas/administración & dosificación , Trabectedina , Células Tumorales Cultivadas
14.
Acta Neuropathol Commun ; 10(1): 65, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35484633

RESUMEN

Glioblastoma (GBM) is characterized by a particularly invasive phenotype, supported by oncogenic signals from the fibroblast growth factor (FGF)/ FGF receptor (FGFR) network. However, a possible role of FGFR4 remained elusive so far. Several transcriptomic glioma datasets were analyzed. An extended panel of primary surgical specimen-derived and immortalized GBM (stem)cell models and original tumor tissues were screened for FGFR4 expression. GBM models engineered for wild-type and dominant-negative FGFR4 overexpression were investigated regarding aggressiveness and xenograft formation. Gene set enrichment analyses of FGFR4-modulated GBM models were compared to patient-derived datasets. Despite widely absent in adult brain, FGFR4 mRNA was distinctly expressed in embryonic neural stem cells and significantly upregulated in glioblastoma. Pronounced FGFR4 overexpression defined a distinct GBM patient subgroup with dismal prognosis. Expression levels of FGFR4 and its specific ligands FGF19/FGF23 correlated both in vitro and in vivo and were progressively upregulated in the vast majority of recurrent tumors. Based on overexpression/blockade experiments in respective GBM models, a central pro-oncogenic function of FGFR4 concerning viability, adhesion, migration, and clonogenicity was identified. Expression of dominant-negative FGFR4 resulted in diminished (subcutaneous) or blocked (orthotopic) GBM xenograft formation in the mouse and reduced invasiveness in zebrafish xenotransplantation models. In vitro and in vivo data consistently revealed distinct FGFR4 and integrin/extracellular matrix interactions. Accordingly, FGFR4 blockade profoundly sensitized FGFR4-overexpressing GBM models towards integrin/focal adhesion kinase inhibitors. Collectively, FGFR4 overexpression contributes to the malignant phenotype of a highly aggressive GBM subgroup and is associated with integrin-related therapeutic vulnerabilities.


Asunto(s)
Glioblastoma , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos , Animales , Carcinogénesis , Glioblastoma/genética , Glioblastoma/patología , Humanos , Integrinas , Ratones , Recurrencia Local de Neoplasia , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos/genética , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos/metabolismo , Pez Cebra/metabolismo , Proteínas de Pez Cebra
15.
Exp Dermatol ; 19(12): 1040-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21087322

RESUMEN

Aurora kinases represent promising novel cancer therapy targets. Genomic analyses of human cutaneous melanoma (CMM) models (N = 51, low passage) by classical and/or array CGH revealed frequent gains at chromosome 20q (65%, amplifications in 45%) repeatedly including the Aurora A gene locus. Accordingly, the majority of CMM cell cultures overexpressed Aurora A when compared to proliferating non-malignant cells. Moreover, CMM cells even when arrested in G1/S cell cycle phase contained readily detectable levels of Aurora A indicating incomplete degradation during mitosis. Already at low concentrations (10-100 nm), long-term (7-10 days) application of the pan-Aurora kinase inhibitor VE-465 completely prevented colony formation in all CMM models tested. In contrast, blockade of cell survival/proliferation and DNA synthesis as well as the induction of apoptosis by VE-465 distinctly differed in short-term experiments (up to 72 h exposure). Both cell cycle arrest and DNA synthesis blockade depended on the level of VE-465-mediated p53/p21 activation while p53/p21 unresponsiveness led to repetitive endoreduplication (>8n DNA content). In contrast, apoptosis induction by VE-465 and Aurora A siRNA did not correlate with p53/p21 responsiveness and DNA synthesis blockade. Moreover, application of the Aurora B-specific inhibitor ZM447439 and siRNA was less efficient to induce CMM cell death proofing that apoptosis induction by VE-465 depended predominantly on Aurora A targeting. In combination experiments with chemotherapeutic agents, VE-465 acted additive to antagonistic when applied concomitantly but in several cases even synergistic when applied consecutively. In summary, we suggest that the Aurora A kinase might represent a promising target of well-designed novel antimelanoma strategies.


Asunto(s)
Melanoma/tratamiento farmacológico , Melanoma/patología , Piperazinas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Aurora Quinasa B , Aurora Quinasas , Caspasa 7/metabolismo , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cromosomas Humanos/genética , Sinergismo Farmacológico , Amplificación de Genes/genética , Células HCT116 , Humanos , Melanoma/enzimología , Melanoma/genética , Células Madre Neoplásicas/efectos de los fármacos , Poliploidía , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Interferente Pequeño/genética , Células Tumorales Cultivadas/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo
16.
Anticancer Res ; 40(11): 6229-6236, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33109560

RESUMEN

BACKGROUND/AIM: To compare the GeneXpert® O6-methylguanine DNA methyltransferase (MGMT) methylation prototype (GX MGMT) assay with pyrosequencing in glioblastomas. MATERIALS AND METHODS: The MGMT methylation status was retrospectively assessed in formalin-fixed paraffin embedded (FFPE) tumor blocks from 262 glioblastoma patients obtained from three independent cohorts using either a standard of care pyrosequencing laboratory developed test or the GX MGMT assay. RESULTS: The concordance rate was 92.1% (58/63) for Oregon Health and Science University (OSHU) samples, 91.7% (88/96) for Medical University of Vienna (MUV) samples, and 82.5% (85/103) for Kepler University Hospital (KUH) samples. Patients with MGMT promoter hypermethylation assessed by pyrosequencing or the GX MGMT test had a significantly longer overall survival compared to patients without hypermethylation (HR=0.43, 95%CI=0.26-0.72, p=0.001 and HR=0.51, 95%CI=0.31-0.84, p=0.008, respectively). CONCLUSION: Standardized, simplified, and on-demand testing of MGMT promoter methylation by the GX MGMT assay is feasible.


Asunto(s)
Bioensayo/métodos , Neoplasias Encefálicas/genética , Metilación de ADN/genética , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Glioblastoma/genética , Reacción en Cadena de la Polimerasa/métodos , Regiones Promotoras Genéticas , Proteínas Supresoras de Tumor/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Adulto Joven
17.
Neoplasia ; 22(2): 61-75, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31846834

RESUMEN

Malignant cells ensure telomere maintenance by the alternative lengthening of telomeres (ALT) in the absence of telomerase activity (TA). The retrotransposons "long interspersed nuclear element-1" (LINE-1, L1) are expressed in malignant cells and are primarily known to contribute to complex karyotypes. Here we demonstrate that LINE-1 ribonucleoprotein particles (L1-RNPs) expression is significantly higher in ALT+- versus in TA+-human glioma. Analyzing a role of L1-RNP in ALT, we show that L1-RNPs bind to telomeric repeat containing RNA (TERRA), which is critical for telomere stabilization and which is overexpressed in ALT+ cells. In turn, L1-RNP knockdown (KD) abrogated the nuclear retention of TERRA, resulted in increased telomeric DNA damage, decreased cell growth and reduced expression of ALT characteristics such as c-circles and PML-bodies. L1-RNP KD also decreased the expression of Shelterin- and the ALT-regulating protein Topoisomerase IIIα (TopoIIIα) indicating a more general role of L1-RNPs in supporting telomeric integrity in ALT. Our findings suggest an impact of L1-RNP on telomere stability in ALT+ dependent tumor cells. As L1-RNPs are rarely expressed in normal adult human tissue those elements might serve as a novel target for tumor ablative therapy.


Asunto(s)
ADN-Topoisomerasas de Tipo I/genética , Proteínas de Unión al ADN/genética , Glioma/genética , Telómero/genética , Factores de Transcripción/genética , Línea Celular Tumoral , Daño del ADN/genética , Glioma/patología , Humanos , Elementos de Nucleótido Esparcido Largo/genética , Ribonucleoproteínas/genética , Homeostasis del Telómero/genética
18.
Cancers (Basel) ; 12(11)2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33143299

RESUMEN

The small-molecule E26 transformation-specific (ETS) factor inhibitor YK-4-279 was developed for therapy of ETS/EWS fusion-driven Ewing's sarcoma. Here we aimed to identify molecular factors underlying YK-4-279 responsiveness in ETS fusion-negative cancers. Cell viability screenings that deletion of P53 induced hypersensitization against YK-4-279 especially in the BRAFV600E-mutated colon cancer model RKO. This effect was comparably minor in the BRAF wild-type HCT116 colon cancer model. Out of all ETS transcription factor family members, especially ETS1 overexpression at mRNA and protein level was induced by deletion of P53 specifically under BRAF-mutated conditions. Exposure to YK-4-279 reverted ETS1 upregulation induced by P53 knock-out in RKO cells. Despite upregulation of p53 by YK-4-279 itself in RKOp53 wild-type cells, YK-4-279-mediated hyperphosphorylation of histone histone H2A.x was distinctly more pronounced in the P53 knock-out background. YK-4-279-induced cell death in RKOp53-knock-out cells involved hyperPARylation of PARP1, translocation of the apoptosis-inducible factor AIF into nuclei, and induction of mitochondrial membrane depolarization, all hallmarks of parthanatos. Accordingly, pharmacological PARP as well as BRAFV600E inhibition showed antagonistic activity with YK-4-279 especially in the P53 knock-out background. Taken together, we identified ETS factor inhibition as a promising strategy for the treatment of notoriously therapy-resistant p53-null solid tumours with activating MAPK mutations.

19.
NPJ Vaccines ; 5(1): 5, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31969991

RESUMEN

Glioblastoma is the most prevalent and aggressive brain cancer. With a median overall survival of ~15-20 months under standard therapy, novel treatment approaches are desperately needed. A recent phase II clinical trial with a personalized immunotherapy based on tumor lysate-charged dendritic cell (DC) vaccination, however, failed to prolong survival. Here, we investigated tumor tissue from trial patients to explore glioblastoma survival-related factors. We followed an innovative approach of combining mass spectrometry-based quantitative proteomics (n = 36) with microRNA sequencing plus RT-qPCR (n = 38). Protein quantification identified, e.g., huntingtin interacting protein 1 (HIP1), retinol-binding protein 1 (RBP1), ferritin heavy chain (FTH1) and focal adhesion kinase 2 (FAK2) as factor candidates correlated with a dismal prognosis. MicroRNA analysis identified miR-216b, miR-216a, miR-708 and let-7i as molecules potentially associated with favorable tissue characteristics as they were enriched in patients with a comparably longer survival. To illustrate the utility of integrated miRNomics and proteomics findings, focal adhesion was studied further as one example for a pathway of potential general interest. Taken together, we here mapped possible drivers of glioblastoma outcome under immunotherapy in one of the largest DC vaccination tissue analysis cohorts so far-demonstrating usefulness and feasibility of combined proteomics/miRNomics approaches. Future research should investigate agents that sensitize glioblastoma to (immuno)therapy-potentially building on insights generated here.

20.
World Neurosurg ; 133: e583-e591, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31561040

RESUMEN

OBJECTIVE: To assess the prognostic profile, clinical outcome, treatment-associated morbidity, and treatment burden of elderly patients with glioblastoma (GBM) undergoing microsurgical tumor resection as part of contemporary treatment algorithms. METHODS: We retrospectively identified patients with GBM ≥65 years of age who were treated by resection at 2 neuro-oncology centers. Survival was assessed by Kaplan-Meier analyses; log-rank tests identified prognostic factors. RESULTS: The study population included 160 patients (mean age, 73.1 ± 5.1 years), and the median contrast-enhancing tumor volume was 31.0 cm3. Biomarker analyses revealed O(6)-methylguanine-DNA methyltransferase-promoter methylation in 62.7% and wild-type isocitrate dehydrogenase in 97.5% of tumors. The median extent of resection (EOR) was 92.3%, surgical complications were noted in 10.0% of patients, and the median postoperative hospitalization period was 8 days. Most patients (60.0%) received adjuvant radio-/chemotherapy. The overall treatment-associated morbidity was 30.6%. The median progression-free and overall survival were 5.4 months (95% confidence interval [CI], 4.6-6.4 months) and 10.0 months (95% CI, 7.9-11.7 months). The strongest predictors for favorable outcome were patient age ≤73.0 years (P = 0.0083), preoperative Karnofsky Performance Status Scale score ≥80% (P = 0.0179), postoperative modified Rankin Scale score ≤1 (P < 0.0001), adjuvant treatment (P < 0.0001), and no treatment-associated morbidity (P = 0.0478). Increased EOR did not correlate with survival (P = 0.5046), but correlated significantly with treatment-associated morbidity (P = 0.0031). CONCLUSIONS: Clinical outcome for elderly patients with GBM remains limited. Nonetheless, the observed treatment-associated morbidity and treatment burden were moderate in the patients, and patient age and performance status remained the strongest predictors for survival. The risks and benefits of tumor resection in the age of biomarker-adjusted treatment concepts require further prospective evaluation.


Asunto(s)
Neoplasias Encefálicas/cirugía , Glioblastoma/cirugía , Procedimientos Neuroquirúrgicos , Anciano , Anciano de 80 o más Años , Austria , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Femenino , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
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