RESUMO
Glioma stem cells (GSCs) are glioblastoma (GBM) cells that are resistant to therapy and can give rise to recurrent tumors. The identification of patient-related factors that support GSCs is thus necessary to design effective therapies for GBM patients. Glucocorticoids (GCs) are used to treat GBM-associated edema. However, glucocorticoids participate in the physiological response to psychosocial stress, which has been linked to poor cancer prognosis. This raises concern that glucocorticoids affect the tumor and GSCs. Here, we treated primary human GBM cells with dexamethasone and evaluated GC-driven changes in cell morphology, proliferation, migration, gene expression, secretory activity and growth as neurospheres. Dexamethasone treatment of GBM cells appeared to promote the development of a GSC-like phenotype and conferred resistance to physiological stress and chemotherapy. We also analyzed a potential correlation between GC treatment and tumor recurrence after surgical excision in a population-based consecutive cohort of 48 GBM patients, adjusted for differences in known prognostic factors concerning baseline and treatment characteristics. In this cohort, we found a negative correlation between GC intake and progression-free survival, regardless of the MGMT methylation status. In conclusion, our findings raise concern that treatment of GBM with GCs may compromise the efficacy of chemotherapy and may support a GSC population, which could contribute to tumor recurrence and the poor prognosis of the disease.
Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/terapia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/terapia , Glucocorticoides/efeitos adversos , Recidiva Local de Neoplasia/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Encéfalo/patologia , Encéfalo/cirurgia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Quimiorradioterapia Adjuvante/métodos , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Feminino , Glioblastoma/complicações , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Procedimentos Neurocirúrgicos , Cultura Primária de Células , Prognóstico , Estresse Fisiológico/efeitos dos fármacos , Resultado do Tratamento , Células Tumorais CultivadasRESUMO
BACKGROUND: Glioblastoma (GBM) is the most common malignant brain tumor with median survival of 12-15 months. Owing to uncertainty in clinical outcome, additional prognostic marker(s) apart from existing markers are needed. Since overexpression of endothelin B receptor (ETBR) has been demonstrated in gliomas, we aimed to test whether ETBR is a useful prognostic marker in GBM and examine if the clinically available endothelin receptor antagonists (ERA) could be useful in the disease treatment. METHODS: Data from The Cancer Genome Atlas and the Gene Expression Omnibus database were analyzed to assess ETBR expression. For survival analysis, glioblastoma samples from 25 Swedish patients were immunostained for ETBR, and the findings were correlated with clinical history. The druggability of ETBR was assessed by protein-protein interaction network analysis. ERAs were analyzed for toxicity in in vitro assays with GBM and breast cancer cells. RESULTS: By bioinformatics analysis, ETBR was found to be upregulated in glioblastoma patients, and its expression levels were correlated with reduced survival. ETBR interacts with key proteins involved in cancer pathogenesis, suggesting it as a druggable target. In vitro viability assays showed that ERAs may hold promise to treat glioblastoma and breast cancer. CONCLUSIONS: ETBR is overexpressed in glioblastoma and other cancers and may be a prognostic marker in glioblastoma. ERAs may be useful for treating cancer patients.
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Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Receptor de Endotelina B/genética , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Antagonistas dos Receptores de Endotelina/uso terapêutico , Feminino , Redes Reguladoras de Genes , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Prognóstico , Receptor de Endotelina B/metabolismoRESUMO
INTRODUCTION: A pilot study of temozolomide (TMZ) given before radiotherapy (RT) for anaplastic astrocytoma (AA) and glioblastoma (GBM) resulted in prolonged survival compared to historical controls receiving RT alone. We therefore investigated neoadjuvant TMZ (NeoTMZ) in a randomized trial. During enrollment, concomitant and adjuvant radio-chemotherapy with TMZ became standard treatment. The trial was amended to include concurrent TMZ. PATIENTS AND METHODS: Patients, after surgery for GBM or AA, age ≤60 years and performance status (PS) 0-2, were randomized to either 2-3 cycles of TMZ, 200 mg/m2 days 1-5 every 28 days, followed by RT 60 Gy in 30 fractions or RT only. Patients without progressive disease after two TMZ cycles, received the third cycle. From March 2005, TMZ 75 mg/m2 was administered daily concomitant with RT. TMZ was recommended first-line treatment at progression. Primary endpoint was overall survival and secondary safety. RESULTS: The study closed prematurely after enrolling 144 patients, 103 with GBM and 41 with AA. Median age was 53 years (range 24-60) and 89 (62%) were male. PS was 0-1 for 133 (92%) patients, 53 (37%) had complete surgical resection and 18 (12%) biopsy. Ninety-two (64%) received TMZ concomitant with RT. Seventy-two (50%) were randomized to neoadjuvant treatment. For the overall study population survival was 20.3 months for RT and 17.7 months for NeoTMZ (p = .76), this not reaching the primary objective. For the preplanned subgroup analysis, we found that NeoTMZ AA patients had a median survival of 95.1 months compared to 35.2 months for RT (p = .022). For patients with GBM, no difference in survival was observed (p = .10). MGMT and IDH status affected outcome. CONCLUSIONS: No advantage of NeoTMZ was noted for the overall study population or subgroup of GBM, while NeoTMZ resulted in 5 years longer median survival for patients diagnosed as AA.
Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Astrocitoma/terapia , Neoplasias Encefálicas/terapia , Quimiorradioterapia Adjuvante/métodos , Dacarbazina/análogos & derivados , Glioblastoma/terapia , Procedimentos Neurocirúrgicos , Radioterapia Adjuvante/métodos , Adulto , Astrocitoma/genética , Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/uso terapêutico , Feminino , Glioblastoma/genética , Humanos , Isocitrato Desidrogenase/genética , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mutação , Projetos Piloto , Prognóstico , Regiões Promotoras Genéticas , Taxa de Sobrevida , Temozolomida , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Proteína Nuclear Ligada ao X/genética , Adulto JovemRESUMO
Importance: Tumor-treating fields (TTFields) is an antimitotic treatment modality that interferes with glioblastoma cell division and organelle assembly by delivering low-intensity alternating electric fields to the tumor. Objective: To investigate whether TTFields improves progression-free and overall survival of patients with glioblastoma, a fatal disease that commonly recurs at the initial tumor site or in the central nervous system. Design, Setting, and Participants: In this randomized, open-label trial, 695 patients with glioblastoma whose tumor was resected or biopsied and had completed concomitant radiochemotherapy (median time from diagnosis to randomization, 3.8 months) were enrolled at 83 centers (July 2009-2014) and followed up through December 2016. A preliminary report from this trial was published in 2015; this report describes the final analysis. Interventions: Patients were randomized 2:1 to TTFields plus maintenance temozolomide chemotherapy (n = 466) or temozolomide alone (n = 229). The TTFields, consisting of low-intensity, 200 kHz frequency, alternating electric fields, was delivered (≥ 18 hours/d) via 4 transducer arrays on the shaved scalp and connected to a portable device. Temozolomide was administered to both groups (150-200 mg/m2) for 5 days per 28-day cycle (6-12 cycles). Main Outcomes and Measures: Progression-free survival (tested at α = .046). The secondary end point was overall survival (tested hierarchically at α = .048). Analyses were performed for the intent-to-treat population. Adverse events were compared by group. Results: Of the 695 randomized patients (median age, 56 years; IQR, 48-63; 473 men [68%]), 637 (92%) completed the trial. Median progression-free survival from randomization was 6.7 months in the TTFields-temozolomide group and 4.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.52-0.76; P < .001). Median overall survival was 20.9 months in the TTFields-temozolomide group vs 16.0 months in the temozolomide-alone group (HR, 0.63; 95% CI, 0.53-0.76; P < .001). Systemic adverse event frequency was 48% in the TTFields-temozolomide group and 44% in the temozolomide-alone group. Mild to moderate skin toxicity underneath the transducer arrays occurred in 52% of patients who received TTFields-temozolomide vs no patients who received temozolomide alone. Conclusions and Relevance: In the final analysis of this randomized clinical trial of patients with glioblastoma who had received standard radiochemotherapy, the addition of TTFields to maintenance temozolomide chemotherapy vs maintenance temozolomide alone, resulted in statistically significant improvement in progression-free survival and overall survival. These results are consistent with the previous interim analysis. Trial Registration: clinicaltrials.gov Identifier: NCT00916409.
Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Terapia por Estimulação Elétrica , Glioblastoma/tratamento farmacológico , Adulto , Idoso , Antineoplásicos Alquilantes/efeitos adversos , Quimiorradioterapia , Dacarbazina/efeitos adversos , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Feminino , Seguimentos , Glioblastoma/radioterapia , Glioblastoma/cirurgia , Humanos , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Mitose , Análise de Sobrevida , TemozolomidaRESUMO
A lack of gap junctional intercellular communication (GJIC) is common in cancer. Many oncogenic viruses have been shown to downregulate the junctional protein connexin 43 (Cx43) and reduce GJIC. Human cytomegalovirus (HCMV) is a ubiquitous, species-specific betaherpesvirus that establishes life-long latency after primary infection. It encodes two viral gene products, immediate early (IE) proteins IE1 and IE2, which are crucial in viral replication and pathogenesis of many diseases. Emerging evidence demonstrates that HCMV DNA and proteins are highly prevalent in glioblastoma multiforme (GBM) and in other tumors, but HCMV's role in tumorigenesis remains obscure. In the present study, we examined the effects of HCMV infection on Cx43 expression and GJIC as well as the viral mechanism mediating the effects in human GBM cells and tissue samples. We found that HCMV downregulated Cx43 protein, resulting in disruption of functional GJIC as assayed by fluorescent dye transfer assay. We show that both HCMV-IE72 and IE86 mediate downregulation of Cx43 by silencing RNA targeting either IE72 or IE86 coupled with ganciclovir. This finding was further validated by transfection with expression vectors encoding IE72 or IE86, and we show that viral-mediated Cx43 depletion involved proteasomal degradation. Importantly, we also observed that the Cx43 protein levels and IE staining correlated inversely in 10 human GBM tissue specimens. Thus, HCMV regulates Cx43 expression and GJIC, which may contribute to gliomagenesis.
Assuntos
Neoplasias do Sistema Nervoso Central/virologia , Conexina 43/metabolismo , Infecções por Citomegalovirus/metabolismo , Junções Comunicantes/metabolismo , Glioblastoma/virologia , Proteínas Imediatamente Precoces/metabolismo , Transativadores/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Conexina 43/genética , Citomegalovirus/metabolismo , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/virologia , Fibroblastos/metabolismo , Fibroblastos/virologia , Glioblastoma/patologia , Humanos , Proteínas Imediatamente Precoces/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Transativadores/genética , Células Tumorais CultivadasRESUMO
Cytomegalovirus is highly prevalent in glioblastomas. In 2006, we initiated a randomized, double-blind, placebo-controlled, hypothesis-generating study to examine the safety and potential efficacy of Valganciclovir as an add-on therapy for glioblastoma. Forty-two glioblastoma patients were randomized in double-blind fashion to receive Valganciclovir or placebo in addition to standard therapy for 6 months. Magnetic resonance images were obtained before and immediately and 3 and 6 months after surgery to evaluate treatment efficacy by measuring contrast enhancing tumor volume (primary end point). Survival data were analyzed for patients and controls in explorative analyses to aid the design of future randomized trials. Trends but no significant differences were observed in tumor volumes in Valganciclovir and placebo patients at 3 (3.58 vs. 7.44 cm3, respectively, p = 0.2881) and 6 (3.31 vs. 13.75 cm3, p = 0.2120) months. Median overall survival (OS) was similar in both groups (17.9 vs. 17.4 months, p = 0.430). Patients could take Valganciclovir for compassionate use after the study phase. Explorative analyses showed an OS of 24.1 months (95% CI, 17.4-40.3) in patients receiving >6 months of Valganciclovir (Val > 6M) versus 13.1 months (95% CI, 7.9-17.7, p < 0.0001) in patients receiving Valganciclovir for 0 or <6 months, and 13.7 months (95% CI, 6.9-17.3, p = 0.0031) in contemporary controls. OS at 4 years was 27.3% in Val>6M patients versus 5.9% in controls (p = 0.0466). Prolonged OS in Val>6M patients suggest that future randomized trials are warranted and should evaluate whether continuous antiviral treatment can improve outcome in glioblastoma patients.
Assuntos
Antivirais/uso terapêutico , Neoplasias Encefálicas/virologia , Citomegalovirus/efeitos dos fármacos , Ganciclovir/análogos & derivados , Glioblastoma/virologia , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Método Duplo-Cego , Feminino , Ganciclovir/efeitos adversos , Ganciclovir/uso terapêutico , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , ValganciclovirRESUMO
OBJECTIVES: Non-small cell lung cancer (NSCLC) with brain metastases (BM) is a challenging clinical issue with poor prognosis. No data exist regarding extensive genetic analysis of cerebrospinal fluid (CSF) and its correlation to associated tumor compartments. MATERIALS AND METHODS: We designed a study across multiple NSCLC patients with matched material from four compartments; primary tumor, BM, plasma and CSF. We performed enrichment-based targeted next-generation sequencing analysis of ctDNA and exosomal RNA in CSF and plasma and compared the outcome with the solid tumor compartments. RESULTS: An average of 105 million reads per sample was generated with fractions of mapped reads exceeding 99% in all samples and with a mean coverage above 10,000x. We observed a high degree of overlap in variants between primary lung tumor and BM. Variants specific for the BM/CSF compartment included in-frame deletions in AR, FGF10 and TSC1 and missense mutations in HNF1a, CD79B, BCL2, MYC, TSC2, TET2, NRG1, MSH3, NOTCH3, VHL and EGFR. CONCLUSION: Our approach of combining ctDNA and exosomal RNA analyses in CSF presents a potential surrogate for BM biopsy. The specific variants that were only observed in the CNS compartments could serve as targets for individually tailored therapies in NSCLC patients with BM.
Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Mutação/genética , Biópsia Líquida , Neoplasias Encefálicas/genéticaRESUMO
Glioblastoma invariably recurs despite aggressive and multimodal first-line treatment and no standardized second-line therapy exists. We previously reported that treatment with the antiviral drug valganciclovir as an add-on to standard therapy significantly prolonged overall survival in 102 patients with newly diagnosed glioblastoma compared to contemporary controls. Here we present the results of retrospective survival analyses including patients with glioblastoma that initiated valganciclovir therapy after recurrence. Twenty-nine patients with recurrent glioblastoma received valganciclovir as an add-on to second-line therapy at Karolinska University Hospital. Contemporary controls were 109 patients with glioblastoma who received similar second-line therapy at our institution. We retrospectively analyzed survival data of these patients. Patients with recurrent glioblastoma who received valganciclovir had longer median overall survival after recurrence than controls (12.1 vs. 7.4 months, respectively, p = 0.0028). The drug was well tolerated. Both patients who underwent re-operation and patients that were not re-operated after recurrence benefitted significantly from valganciclovir therapy. Valganciclovir prolonged survival after recurrence both in patients with an unmethylated and methylated MGMT promoter gene. Valganciclovir was safe to use and prolonged median survival after recurrence for patients with recurrent glioblastoma, re-operated or not after recurrence, and with methylated or unmethylated MGMT promoter gene.
Assuntos
Antivirais/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Ganciclovir/análogos & derivados , Glioblastoma/tratamento farmacológico , Animais , Neoplasias Encefálicas/mortalidade , Quimioterapia Combinada , Ganciclovir/uso terapêutico , Glioblastoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Estudos Retrospectivos , Taxa de Sobrevida , ValganciclovirRESUMO
BACKGROUND: There is an urgent need for effective treatments against glioblastoma (GBM). In this trial, we investigated the efficacy and safety of an adoptive cell-based immunotherapy. METHODS: Patients with newly diagnosed GBM were recruited at 4 study sites in Sweden. The patients were randomized 1:2 to receive either radiotherapy (RT), 60 Gy/30 fractions, with concomitant and adjuvant temozolomide (TMZ) only, or RT and TMZ with the addition of Autologous Lymphoid Effector Cells Specific Against Tumor (ALECSAT) in an open-label phase II trial. The primary endpoint was investigator-assessed progression-free survival (PFS). The secondary endpoints were survival and safety of ALECSAT. RESULTS: Sixty-two patients were randomized to either standard of care (SOC) with RT and TMZ alone (n = 22) or SOC with ALECSAT (n = 40). Median age was 57 years (range 38-69), 95% of the patients were in good performance status (WHO 0-1). There was no significant difference between the study arms (SOC vs ALECSAT + SOC) in PFS (7.9 vs 7.8 months; hazard ratio [HR] 1.28; 95% confidence interval [CI] 0.70-2.36; P = .42) or in median overall survival (OS) (18.3 vs 19.2 months; HR 1.16, 95% CI 0.58-2.31; P = .67). The treatment groups were balanced in terms of serious adverse events (52.4% vs 52.5%), but adverse events ≥grade 3 were more common in the experimental arm (81.0% vs 92.5%). CONCLUSION: Addition of ALECSAT immunotherapy to standard treatment with radiochemotherapy was well tolerated but did not improve PFS or OS for patients with newly diagnosed GBM.
RESUMO
We investigated the presence of cognitive impairment, in adults with presumed low-grade glioma at early stage of disease prior to major treatments, in relation to neurological symptoms and radiological characteristics of the tumour. Sixteen patients were evaluated. A subset of patients was identified with clearly impaired cognition. Patients with cognitive impairment often had large tumours in the left frontal lobe, were relatively young, and most of them were males. We conclude that cognitive dysfunction may be present already at early stage of disease, and that early identification of patients at risk is warranted.
Assuntos
Neoplasias Encefálicas/complicações , Transtornos Cognitivos/etiologia , Cognição , Lobo Frontal/patologia , Glioma/complicações , Imageamento por Ressonância Magnética , Adulto , Fatores Etários , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/psicologia , Estudos de Casos e Controles , Transtornos Cognitivos/patologia , Transtornos Cognitivos/psicologia , Feminino , Glioma/diagnóstico , Glioma/patologia , Glioma/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fatores de TempoRESUMO
Patients with glioblastoma have a very poor prognosis despite aggressive therapeutic strategies. Cytomegalovirus has been detected in >90% of glioblastoma tumors. This virus can affect tumor progression and may represent a novel glioblastoma therapy target. We report, here, a retrospective survival analysis of patients with secondary glioblastoma who were treated with the anti-viral drug valganciclovir at Karolinska University Hospital in Stockholm. We performed survival analyses of eight patients with secondary glioblastoma who were treated with a standard dose of valganciclovir as an add-on to second-line therapy after their disease progression to glioblastoma. Thirty-six patients with secondary glioblastoma admitted during the same time period who received similar treatment and care served as contemporary controls. The patients treated with valganciclovir showed an increased median overall survival after progression to glioblastoma compared with controls (19.1 versus 12.7 months, p = 0.0072). This result indicates a potential positive effect of valganciclovir in secondary glioblastoma, which is in agreement with our previous observation that valganciclovir treatment improves the outcomes of patients with newly diagnosed glioblastoma. Larger randomized studies are warranted to prove this hypothesis.
RESUMO
PURPOSE: Several groups have reported a prevalence of human cytomegalovirus (CMV) in glioblastoma close to 100%. Previously, we reported that treatment with the antiviral drug valganciclovir as an add-on to standard therapy significantly prolonged survival in 50 patients with glioblastoma. Here, we present an updated retrospective analysis that includes an additional 52 patients. EXPERIMENTAL DESIGN: From December 2006 to November 2019, 102 patients with newly diagnosed glioblastoma received valganciclovir as an add-on to standard therapy. No additional toxicity was observed. Contemporary controls were 231 patients with glioblastoma who received similar baseline therapy. RESULTS: Patients with newly diagnosed glioblastoma receiving valganciclovir had longer median overall survival (OS 24.1 vs. 13.3 months, P < 0.0001) and a 2-year survival rate (49.8% vs. 17.3%) than controls. Median time-to-tumor progression was also longer than in controls; 9.9 (0.7-67.5 months) versus 7.3 (1.2-49 months), P = 0.0003. Valganciclovir improved survival in patients with radical or partial resection and an unmethylated or methylated MGMT promoter gene. CONCLUSIONS: Valganciclovir prolonged median OS of patients with newly diagnosed glioblastoma (with methylated or unmethylated MGMT promoter gene) and was safe to use.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Valganciclovir/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Progressão da Doença , Feminino , Glioblastoma/diagnóstico , Glioblastoma/genética , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Proteínas Supressoras de Tumor/genética , Valganciclovir/efeitos adversos , Adulto JovemRESUMO
Glioblastoma (GBM) is the most aggressive form of brain tumor in adults, with a devastating outcome. Emerging evidence shows that human cytomegalovirus (HCMV) proteins and nucleic acids are present in GBM tissues. DNA methylation is important for the initiation and progression of cancer and is an established host response against invading nucleic acids. The expression and localization of DNA methyltransferase 1 (DNMT1) was assessed, and the effects of DNA methylation inhibitor 5azacytidine (5AZA) were analyzed in the context of the viral replication, proliferation and invasion capacities of HCMVinfected GBM U343MG cells. In addition, the expression of various HCMV proteins and DNMT1 was examined in GBM tissue specimens obtained from five patients. DNMT1 was localized in the nucleus of cells expressing HCMVimmediate early, whereas in cells expressing HCMVglycoprotein gB (gB), extranuclear/cytoplasmic localization was observed. This was also observed in vitro in U343MG cells. In addition, DNMT1 was localized to the extranuclear/cytoplasmic space of cells lining blood vessel walls within the GBM tumors. Treatment of infected U343MG cells with 5AZA did not affect viral replication, but reduced cell invasion and proliferation (P=0.05 and P<0.0001, respectively). However, 5AZA treatment of uninfected cells did not affect cell invasion (P=0.09), but proliferation was significantly reduced (P<0.0001). These findings may be of importance in further investigations aimed at using DNA methylation and viral inhibitors in GBM therapy.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Glioblastoma/tratamento farmacológico , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Azacitidina/uso terapêutico , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/patogenicidade , Citomegalovirus/fisiologia , Citoplasma/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Metilação de DNA/efeitos dos fármacos , Progressão da Doença , Feminino , Glioblastoma/patologia , Glioblastoma/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Proteínas do Envelope Viral/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
Medulloblastomas are the most common, and often fatal, paediatric brain tumours that feature high genomic instability, frequent infection by human cytomegalovirus (HCMV) and resistance to radiation and chemotherapy. The causes of the pronounced chromosomal instability and its potential links with HCMV infection and/or resistance to genotoxic therapies remain largely unknown. To address these issues, here we have combined immunohistochemical analysis of a series of 25 paediatric medulloblastomas, complemented by medulloblastoma cell culture models including experimental HCMV infection. Using eight established immunohistochemical markers to assess the status of the DDR machinery, we found pronounced endogenous DNA damage signalling (γH2AX marker) and robust constitutive activation of both the ATM-Chk2 and ATR-Chk1 DNA damage checkpoint kinase cascades, yet unexpectedly modest p53 tumour suppressor activation, across our medulloblastoma cohort. Most tumours showed high proliferation (Ki67 marker), variable oxidative DNA damage (8-oxoguanine lesions) and formation of 53BP1 nuclear 'bodies', the latter indicating (along with ATR-Chk1 signalling) endogenous replication stress. The bulk of the clinical specimens also showed expression of HCMV immediate early and late proteins, in comparative analyses using three immunohistochemical protocols. Cell culture experiments validated the chronic endogenous replication stress in medulloblastoma cell lines and showed sharply differential, intriguing responses of normal cells and medulloblastoma cells to HCMV infection, including differential subcellular mislocalization and enhancement of replication stress-related 53BP1 body formation, the latter in cell-non-autonomous manner. Overall, our results strongly indicate that in human medulloblastomas, the DDR checkpoint barrier is widely activated, at least in part due to replication stress. Furthermore, we propose that unorthodox p53 defects other than mutations may allow high proliferation despite the ongoing checkpoint signalling and that the highly prevalent HCMV may impact the medulloblastoma host cell replication stress and DNA repair. Collectively, the scenario we report here likely fuels genomic instability and evolution of medulloblastoma resistance to standard-of-care genotoxic treatments.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Cerebelares/metabolismo , Infecções por Citomegalovirus/metabolismo , Citomegalovirus/metabolismo , Dano ao DNA , Meduloblastoma/metabolismo , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Adolescente , Neoplasias Cerebelares/patologia , Criança , Pré-Escolar , Infecções por Citomegalovirus/patologia , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Meduloblastoma/patologiaRESUMO
Glioblastoma multiforme (GBM) is a highly malignant tumor with a poor outcome that is often positive for human cytomegalovirus (HCMV). GBM patients often have excessive numbers of neutrophils and macrophages near and within the tumor. Here, we characterized the cytokine patterns in the blood of GBM patients with and without Valganciclovir treatment. Furthermore, we determined whether neutrophil activation is related to HCMV status and patient outcome. Blood samples for analyses of cytokines and growth factors were collected from 42 GBM patients at the time of diagnosis (n = 42) and at weeks 12 and 24 after surgery. Blood neutrophils of 28 GBM patients were examined for CD11b expression. The levels of pro- and anti-inflammatory cytokines and chemokines-including interleukin (IL)-1ß, IL-2, IL-6, IL-8, IL-10, IL-12p70, IL-17A, transforming growth factor (TGF)-ß1, interferon-γ, interferon-α, tumor necrosis factor α, and monocyte chemoattractant protein (MCP)-1were analyzed with a bead-based flow cytometry assay. During the first six months after surgery, neutrophil activity was increased in 12 patients and was unchanged or decreased in 16. Patients with increased neutrophil activity had enhanced IL-12p70, high grade HCMV and a shorter time to tumor progression (TTP) than patients without or decreased neutrophil activity (median TTP; 5.4 vs. 12 months, 95% confidence interval; 1.6-10 vs. 0.1-0.6, hazard ratio = 3 vs. 0.4, p = 0.004). The levels of IL-12p70 were significantly decreased in Valganciclovir treated patients (n = 22, T 12W vs. T 24W, p = 0.03). In conclusion, our findings suggest that neutrophil activation is an early sign of tumor progression in GBM patients.
RESUMO
Patients with glioblastoma multiforme (GBM) are immunosuppressed and have a broad range of immunological defects in both innate and adaptive immune responses. GBMs are frequently infected with human cytomegalovirus (HCMV), a virus capable of causing immunosuppression. In 42 HCMV-positive GBM patients in a clinical trial (VIGAS), we investigated T-cell phenotypes in the blood and assessed their relation to survival. Blood was collected before and 3, 12, and 24 weeks after surgery, and the frequency of T-cell subsets was compared with that in 26 age-matched healthy controls. GBM patients had lower levels of CD3 cells than the controls, but had significantly higher levels of CD4+CD28- T cells before and 3 and 12 weeks after surgery and increased levels of CD4+CD57+ and CD4+CD57+CD28+ T cells at all-time points. These T-cell subsets were associated with both immunosenescence and HCMV infection. GBM patients also had higher levels of γδ T cells at all-times after surgery and lower levels of CD4+CD25+ cells before and 3 weeks after surgery than healthy controls. Overall survival was significantly shorter in patients with higher levels of CD4+CD28- T cells (p = 0.025), CD4+CD57+ T (p = 0.025) cells, and CD4+CD28-CD57+CD28- T cells (p < 0.0004) at 3 weeks after surgery. Our findings indicate that signs of immunosenescence in the CD4+ compartment are associated with poor prognosis in patients with HCMV-positive GBMs and may reflect the HCMV activity in their tumors.