RESUMO
Glioblastoma is the most common malignant brain tumor in adults, the survival rate of which has not significantly improved over the past three decades. Therefore, there is an urgent need to develop novel treatment modalities. We previously reported that G1 to S phase transition 1 (GSPT1) depletion induces delayed cell cycle in primary astrocytes. Herein, we examined the potential of GSPT1 as a novel target for glioblastoma therapy. CC-885, a cereblon modulator that degrades GSPT1 by bridging GSPT1 to the CRL4 E3 ubiquitin ligase complex, was administered to nude mice with transplanted brain tumors of U87 glioblastoma cells. The survival period was significantly longer in CC-885 treated mice than in control mice. Furthermore, we generated GSPT1-knockout (KO) U87 cells and GSPT1-KO U87 cells with stable overexpression of FLAG-tagged GSPT1 (Rescued GSPT1-KO). Mice with transplanted GSPT1-KO U87 cells and Rescued GSPT1-KO U87 cells showed significantly longer and similar survival periods, respectively, as those with wild-type (WT) U87 cells. GSPT1-KO U87 cells showed enhanced apoptosis, detected by cleaved PARP1, compared to WT U87 cells. Brain tumors with transplantation of GSPT1-KO U87 cells also showed enhanced apoptosis compared to those with transplantation of WT and Rescued GSPT1-KO U87 cells. GSPT1 expression was confirmed in patients with glioblastoma. However, the clinical study using 87 glioblastoma samples showed that GSPT1 mRNA levels were not associated with overall survival. Taken together, we propose that GSPT1 is an essential protein for glioblastoma growth, but not its malignant characteristics, and that GSPT1 is a potential target for developing glioblastoma therapeutics.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Camundongos Nus , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/metabolismo , Animais , Humanos , Linhagem Celular Tumoral , Camundongos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Apoptose , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: Treatment paradigms for isocitrate dehydrogenase (IDH)-mutant gliomas are rapidly evolving. Although typically indolent and responsive to initial treatment, these tumors invariably recur at a higher grade and require salvage treatment. Homozygous deletion of the tumor suppressor gene CDKN2A/B frequently emerges at recurrence in these tumors, driving poor patient outcomes. We investigated the effect of CDK-Rb pathway blockade on IDH-mutant glioma growth in vitro and in vivo using CDK4/6 inhibitors (CDKi). EXPERIMENTAL DESIGN: Cell viability, proliferation assays, and flow cytometry were used to examine the pharmacologic effect of two distinct CDKi, palbociclib and abemaciclib, in multiple patient-derived IDH-mutant glioma lines. Isogenic models were used to directly investigate the influence of CDKN2A/B status on CDKi sensitivity. Orthotopic xenograft tumor models were used to examine the efficacy and tolerability of CDKi in vivo. RESULTS: CDKi treatment leads to decreased cell viability and proliferative capacity in patient-derived IDH-mutant glioma lines, coupled with enrichment of cells in the G1 phase. CDKN2A inactivation sensitizes IDH-mutant glioma to CDKi in both endogenous and isogenic models with engineered CDKN2A deletion. CDK4/6 inhibitor administration improves survival in orthotopically implanted IDH-mutant glioma models. CONCLUSIONS: IDH-mutant gliomas with deletion of CDKN2A/B are sensitized to CDK4/6 inhibitors. These results support the investigation of the use of these agents in a clinical setting.
Assuntos
Aminopiridinas , Benzimidazóis , Proliferação de Células , Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p15 , Inibidor p16 de Quinase Dependente de Ciclina , Glioma , Isocitrato Desidrogenase , Mutação , Piperazinas , Inibidores de Proteínas Quinases , Piridinas , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Animais , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/genética , Glioma/genética , Glioma/tratamento farmacológico , Glioma/patologia , Camundongos , Inibidor p16 de Quinase Dependente de Ciclina/genética , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/antagonistas & inibidores , Benzimidazóis/farmacologia , Inibidor de Quinase Dependente de Ciclina p15/genética , Aminopiridinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Piridinas/farmacologia , Piridinas/uso terapêutico , Linhagem Celular Tumoral , Deleção de Genes , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , HomozigotoRESUMO
A subset of patients with IDH-mutant glioma respond to inhibitors of mutant IDH (IDHi), yet the molecular underpinnings of such responses are not understood. Here, we profiled by single-cell or single-nucleus RNA-sequencing three IDH-mutant oligodendrogliomas from patients who derived clinical benefit from IDHi. Importantly, the tissues were sampled on-drug, four weeks from treatment initiation. We further integrate our findings with analysis of single-cell and bulk transcriptomes from independent cohorts and experimental models. We find that IDHi treatment induces a robust differentiation toward the astrocytic lineage, accompanied by a depletion of stem-like cells and a reduction of cell proliferation. Furthermore, mutations in NOTCH1 are associated with decreased astrocytic differentiation and may limit the response to IDHi. Our study highlights the differentiating potential of IDHi on the cellular hierarchies that drive oligodendrogliomas and suggests a genetic modifier that may improve patient stratification.
Assuntos
Neoplasias Encefálicas , Diferenciação Celular , Isocitrato Desidrogenase , Mutação , Oligodendroglioma , Oligodendroglioma/genética , Oligodendroglioma/patologia , Oligodendroglioma/tratamento farmacológico , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/antagonistas & inibidores , Humanos , Diferenciação Celular/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/tratamento farmacológico , Linhagem da Célula/efeitos dos fármacos , Receptor Notch1/genética , Receptor Notch1/metabolismo , Proliferação de Células/efeitos dos fármacos , Animais , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Camundongos , Análise de Célula Única/métodosRESUMO
INTRODUCTION: Multidrug chemoimmunotherapy with rituximab, high-dose methotrexate, procarbazine and vincristine (R-MPV) is a standard therapy for younger patients with primary central nervous system lymphoma (PCNSL); however, prospective data regarding its use in elderly patients are lacking. This multi-institutional, non-randomised, phase II trial will assess the efficacy and safety of R-MPV and high-dose cytarabine (HD-AraC) for geriatric patients with newly diagnosed PCNSL. METHODS AND ANALYSIS: Forty-five elderly patients will be included. If R-MPV does not achieve complete response, the patients will undergo reduced-dose, whole-brain radiotherapy comprising 23.4 Gy/13 fractions, followed by local boost radiotherapy comprising 21.6 Gy/12 fractions. After achieving complete response using R-MPV with or without radiotherapy, the patients will undergo two courses of HD-AraC. All patients will undergo baseline geriatric 8 (G8) assessment before HD-AraC and after three, five and seven R-MPV courses. Patients with screening scores of ≥14 points that decrease to <14 points during subsequent treatment, or those with screening scores <14 points that decrease from the baseline during subsequent treatment are considered unfit for R-MPV/HD-AraC. The primary endpoint is overall survival, and the secondary endpoints are progression-free survival, treatment failure-free survival and frequency of adverse events. The results will guide a later phase III trial and provide information about the utility of a geriatric assessment for defining chemotherapy ineligibility. ETHICS AND DISSEMINATION: This study complies with the latest Declaration of Helsinki. Written informed consent will be obtained. All participants can quit the study without penalty or impact on treatment. The protocol for the study, statistical analysis plan and informed consent form have been approved by the Certified Review Board at Hiroshima University (CRB6180006) (approval number: CRB2018-0011). The study is ongoing within nine tertiary and two secondary hospitals in Japan. The findings of this trial will be disseminated through national and international presentations and peer-reviewed publications. TRIAL REGISTRATION: jRCTs061180093.
Assuntos
Neoplasias do Sistema Nervoso Central , Linfoma , Idoso , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Encéfalo/patologia , Sistema Nervoso Central/patologia , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/patologia , Ensaios Clínicos Fase II como Assunto , Citarabina/uso terapêutico , Linfoma/terapia , Metotrexato/uso terapêutico , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Rituximab , Resultado do Tratamento , VincristinaRESUMO
OBJECTIVE: Adult brainstem gliomas (BSGs) are rare tumors of the CNS that are poorly understood. Upregulation of the oncometabolite 2-hydroxyglutarate (2HG) in the tumor indicates the mutation of isocitrate dehydrogenase (IDH), which can be detected by magnetic resonance spectroscopy (MRS). Although histological examination is required for the definitive diagnosis of BSG, 2HG-optimized MRS (2HG-MRS) may be useful, considering the difficult nature of brainstem lesion biopsy. The aim of this study was to evaluate the utility of 2HG-MRS for diagnosing IDH-mutant adult BSG. METHODS: Patients with a radiographically confirmed brainstem tumor underwent 3T MRS. A single voxel was set in the lesion with reference to the T2 or fluid-attenuated inversion recovery image and analyzed according to the 2HG-tailored MRS protocol (point-resolved spectroscopic sequence; echo time 35 msec). All patients underwent intraoperative navigation-guided or CT-guided stereotactic biopsy for histopathological diagnosis. The status of IDH and H3K27M mutations was confirmed by immunohistochemistry and direct DNA sequencing. In addition, the authors examined the relationship between patients' 2HG concentrations and survival time. RESULTS: Ten patients (7 men, 3 women; median age 33.5 years) underwent 2HG-MRS and biopsy. Four patients had an H3K27M mutation and 4 had an IDH1 mutation (1 R132H canonical IDH mutation, 2 R132S and 1 R132G noncanonical IDH mutations). Two had neither H3K27M nor IDH mutations. The H3K27M and IDH mutations were mutually exclusive. Most tumors were located in the pons. There was no significant radiological difference between mutant H3K27M and IDH on a conventional MRI sequence. A 2HG concentration ≥ 1.8 mM on MRS demonstrated 100% (95% CI 28%-100%) sensitivity and 100% (95% CI 42%-100%) specificity for IDH-mutant BSG (p = 0.0048). The median overall survival was 10 months in IDH-wild-type BSG patients (n = 6) and could not be estimated in IDH-mutant BSG patients (n = 4) due to the small number of deaths (p = 0.008). CONCLUSIONS: 2HG-MRS demonstrated high sensitivity and specificity for the prediction of IDH-mutant BSG. In addition, 2HG-MRS may be useful for predicting the prognosis of adult BSG patients.
Assuntos
Neoplasias Encefálicas , Neoplasias do Tronco Encefálico , Glioma , Masculino , Adulto , Humanos , Feminino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Glioma/diagnóstico por imagem , Glioma/genética , Espectroscopia de Ressonância Magnética/métodos , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/genética , Biópsia Guiada por Imagem , Isocitrato Desidrogenase/genética , MutaçãoRESUMO
Ror1 plays a crucial role in cancer progression by regulating cell proliferation and migration. Ror1 is expressed abundantly in various types of cancer cells and cancer stem-like cells. However, the molecular mechanisms regulating expression of Ror1 in these cells remain largely unknown. Ror1 and its putative ligand Wnt5a are expressed highly in malignant gliomas, especially in glioblastomas, and the extents of Ror1 expression are correlated positively with poorer prognosis in patients with gliomas. We show that Ror1 expression can be upregulated in glioblastoma cells under spheroid culture, but not adherent culture conditions. Notch and hypoxia signaling pathways have been shown to be activated in spheroid-forming glioblastoma stem-like cells (GSCs), and Ror1 expression in glioblastoma cells is indeed suppressed by inhibiting either Notch or hypoxia signaling. Meanwhile, either forced expression of the Notch intracellular domain (NICD) in or hypoxic culture of glioblastoma cells result in enhanced expression of Ror1 in the cells. Consistently, we show that both NICD and hypoxia-inducible factor 1 alpha bind to upstream regions within the Ror1 gene more efficiently in GSCs under spheroid culture conditions. Furthermore, we provide evidence indicating that binding of Wnt5a to Ror1, upregulated by Notch and hypoxia signaling pathways in GSCs, might promote their spheroid-forming ability. Collectively, these findings indicate for the first time that Notch and hypoxia signaling pathways can elicit a Wnt5a-Ror1 axis through transcriptional activation of Ror1 in glioblastoma cells, thereby promoting their stem cell-like property.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Glioblastoma/metabolismo , Glioma/patologia , Transdução de Sinais , Hipóxia/patologia , Células-Tronco Neoplásicas/metabolismo , Linhagem Celular Tumoral , Neoplasias Encefálicas/patologia , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismoRESUMO
Owing to recent advances in medical optical technology, a high-definition (4K) three-dimensional (3D) exoscope has been developed as an alternative tool to using conventional microscopes for microscopic surgery, and its efficacy for neurosurgery has been reported. We report a case who underwent simultaneous surgery aiming for en bloc resection of an anterior skull base malignancy with concurrent exoscopic transcranial and endoscopic endonasal approaches using a 4K 3D exoscope. The patient was a 76-year-old woman who underwent en bloc resection for an anterior skull base olfactory neuroblastoma 13 years ago. After confirming the recurrence of progressive olfactory neuroblastoma, tumor resection was again decided to be performed. As with the first procedure, surgery was performed in an en bloc manner, using both transcranial and endonasal approaches. Exoscope provided enough space above the surgical field to allow us to perform transcranial and endonasal surgeries simultaneously. Moreover, the surgeons could maintain a comfortable posture throughout the procedure, and total tumor removal was successfully achieved without any abnormal event. To our knowledge, this is the first report of the introduction of an exoscope aiming for en bloc resection of an anterior skull base malignancy while performing simultaneous surgery with both transcranial and endonasal approaches. We believe that the more cases are accumulated, the more efficacy of a 4K 3D exoscope will be elucidated.
RESUMO
Unruptured middle cerebral artery (MCA) aneurysms often exist bilaterally, and a unilateral approach for bilateral MCA aneurysms has been reported; however, this remains challenging because there are various technical nuances.1-4 Wall properties have been reported to be an important issue for this strategy.2,3 Atherosclerotic changes in the aneurysm wall can make clipping difficult. We present a video case demonstrating clipping of bilateral MCA aneurysms via a unilateral craniotomy assisted by preoperative understanding of the aneurysm wall properties using computational fluid dynamic analysis (Video 1). A 71-year-old woman had bilateral MCA bifurcation aneurysms. The oscillatory shear index color map by computational fluid dynamic analysis demonstrated that the contralateral MCA aneurysm did not have a high oscillatory shear index area in the dome, which means that there was no wall thickening, and the ipsilateral MCA aneurysm had scattered high oscillatory shear index areas, which were expected to have extreme wall thickening.5 After pterional craniotomy, the sylvian fissure was widely opened. As expected, the contralateral MCA aneurysm did not have a thick-walled region, enabling simple neck clipping using a straight clip. In contrast, the ipsilateral MCA aneurysm had thick-walled areas, as predicted, necessitating a multiple clip application. Postoperatively, the patient was discharged without any neurological deficits. Prediction of aneurysm wall properties using computational fluid dynamic analysis could assist in determining clippability of intracranial aneurysms, especially for aneurysms approached by narrow and deep surgical fields, such as contralateral MCA aneurysms. The patient consented to the procedure and the publication of their images.
Assuntos
Meios de Comunicação , Aneurisma Intracraniano , Idoso , Craniotomia/métodos , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Microcirurgia , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/cirurgia , Instrumentos CirúrgicosRESUMO
OBJECTIVE: Epilepsy in glioblastoma patients significantly reduces their quality of life; however, little is known about the association between predicting epilepsy and metabolites in tumors. In this study, we used 3.0-T magnetic resonance imaging and 1H-magnetic resonance spectroscopy (MRS) to quantify metabolite concentrations in patients with varying epilepsy histories. METHODS: Fifty-one patients with glioblastoma underwent pretreatment 3.0-T MRI/1H-MRS scanning. Single-voxel (1.5 cm3) MRS, in an enhanced lesion, was acquired using a double-echo point-resolved spectroscopic sequence with chemical-shift selective water suppression. MRS data were quantified with linear combination model (LC-Model) software. We compared the MRS data between groups with and without epilepsy during the postoperative course (EP). RESULTS: The ratios of glutamate (Glu) and glutamate + glutamine (Glx) to total creatine (Glu/tCr and Glx/tCr) in the tumor were associated with epilepsy history. The receiver operating characteristic curve analysis showed that a Glu/tCr value of 1.81 was 70% sensitive and 90% specific for the prediction of EP (area under curve: 0.82). In the analysis excluding patients with preoperative epilepsy, a Glu/tCr value of 1.81 was 75% sensitive and 88% specific for the prediction (area under curve: 0.87). CONCLUSIONS: Intratumoral metabolite concentrations measured using pretreatment 3.0-T MRI/1H-MRS changed characteristically in the group with EP. Our study suggests that the Glu/tCr ratio in tumors has adequate reliability in predicting EP. Pretreatment MRS is a minimally invasive and simple procedure that can provide useful information on glioblastoma patients.
Assuntos
Epilepsia , Glioblastoma , Creatina/metabolismo , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Glioblastoma/diagnóstico por imagem , Glioblastoma/cirurgia , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos , Qualidade de Vida , Reprodutibilidade dos TestesRESUMO
PURPOSE: Photodynamic therapy (PDT) subsequent to surgical tumor removal is a novel localized treatment for malignant glioma that provides effective local control. The acute response of malignant glioma to PDT can be detected as linear transient hyperintense signal on diffusion-weighted imaging (DWI) and a decline in apparent diffusion coefficient values without symptoms. However, their long-term clinical significance has not yet been examined. The aim of this study was to clarify the link between hyperintense signal on DWI as an acute response and recurrence after PDT in malignant glioma. METHODS: Thirty patients (16 men; median age, 60.5 years) underwent PDT for malignant glioma at our institution between 2017 and 2020. We analyzed the signal changes on DWI after PDT and the relationship between these findings and the recurrence pattern. RESULTS: All patients showed linear hyperintense signal on DWI at the surface of the resected cavity from day 1 after PDT. These changes disappeared in about 30 days without any neurological deterioration. During a mean post-PDT follow-up of 14.3 months, 19 patients (63%) exhibited recurrence: 10 local, 1 distant, and 8 disseminated. All of the local recurrences arose from areas that did not show hyperintense signal on DWI obtained on day 1 after PDT. CONCLUSIONS: The local recurrence in malignant glioma after PDT occurs in an area without hyperintense signal on DWI as an acute response to PDT. This characteristic finding could aid in the monitoring of local recurrence after PDT.
Assuntos
Glioma , Fotoquimioterapia , Imagem de Difusão por Ressonância Magnética , Feminino , Glioma/diagnóstico por imagem , Glioma/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
OBJECTIVE: The T2-FLAIR mismatch sign is a useful imaging sign in clinical magnetic resonance imaging studies for detecting isocitrate dehydrogenase (IDH)-mutant 1p/19q non-codeleted astrocytomas. However, the association between the mismatch sign and pathologic findings is poorly understood. Therefore, the aim of this study was to elucidate the relationship of histopathologic and radiologic features with the mismatch sign in IDH-mutant 1p/19q non-codeleted astrocytomas. METHODS: We divided 17 IDH-mutant 1p/19q non-codeleted patients into 2 groups according to mismatch sign presence (WITH, n = 9; WITHOUT, n = 8) and retrospectively analyzed their pathologic findings and apparent diffusion coefficient (ADC) values. We also compared these findings between the tumor Core (central area) and Rim (marginal area). RESULTS: In the pathologic analysis, Core of the WITH group contained numerous microcysts whereas Rim had abundant neuroglial fibrils and cellularity. In contrast, Core of the WITHOUT group had highly concentrated neuroglial fibrils. In ADC analysis, Core of the WITH group had significantly higher ADC values compared with Rim (P < 0.001). However, there was no significant difference between Core and Rim in the WITHOUT group (P = 0.12). The WITH group had a significantly higher Core/Rim ratio of ADC values compared with the WITHOUT group (P < 0.001). CONCLUSIONS: This study provides evidence that a region-dependent microstructural difference could reflect the mismatch sign in IDH-mutant 1p/19q non-codeleted astrocytomas. Core of the mismatch sign characteristically had microcystic changes accompanied by higher ADC values, whereas Rim had abundant neuroglial fibrils and cellularity accompanied by lower ADC values.
Assuntos
Astrocitoma/diagnóstico por imagem , Astrocitoma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neuroimagem/métodos , Adulto , Idoso , Astrocitoma/genética , Neoplasias Encefálicas/genética , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Mutação , Adulto JovemRESUMO
Cancer cells optimize nutrient utilization to supply energetic and biosynthetic pathways. This metabolic process also includes redox maintenance and epigenetic regulation through nucleic acid and protein methylation, which enhance tumorigenicity and clinical resistance. However, less is known about how cancer cells exhibit metabolic flexibility to sustain cell growth and survival from nutrient starvation. Here, we find that serine and glycine levels were higher in low-nutrient regions of tumors in glioblastoma multiforme (GBM) patients than they were in other regions. Metabolic and functional studies in GBM cells demonstrated that serine availability and one-carbon metabolism support glioma cell survival following glutamine deprivation. Serine synthesis was mediated through autophagy rather than glycolysis. Gene expression analysis identified upregulation of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) to regulate one-carbon metabolism. In clinical samples, MTHFD2 expression was highest in the nutrient-poor areas around "pseudopalisading necrosis." Genetic suppression of MTHFD2 and autophagy inhibition caused tumor cell death and growth inhibition of glioma cells upon glutamine deprivation. These results highlight a critical role for serine-dependent one-carbon metabolism in surviving glutamine starvation and suggest new therapeutic targets for glioma cells adapting to a low-nutrient microenvironment.
Assuntos
Aminoidrolases/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Glutamina/metabolismo , Glicina/metabolismo , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Enzimas Multifuncionais/genética , Serina/metabolismo , Aminoidrolases/metabolismo , Autofagia/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Espectroscopia de Ressonância Magnética , Metabolômica , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Enzimas Multifuncionais/metabolismo , Microambiente Tumoral/genética , Regulação para CimaRESUMO
The ketogenic diet (KD) is a high fat and low carbohydrate diet that produces ketone bodies through imitation of starvation. The combination of KD and Bevacizumab (Bev), a VEGF inhibitor, is considered to further reduce the supply of glucose to the tumor. The metabolite changes in U87 glioblastoma mouse models treated with KD and/or Bev were examined using gas chromatography-mass spectrometry. The combination therapy of KD and Bev showed a decrease in the rate of tumor growth and an increase in the survival time of mice, although KD alone did not have survival benefit. In the metabolome analysis, the pattern of changes for most amino acids are similar between tumor and brain tissues, however, some amino acids such as aspartic acid and glutamic acid were different between tumors and brain tissues. The KD enhanced the anti-tumor efficacy of Bev in a glioblastoma intracranial implantation mouse model, based on lowest levels of microvascular density (CD31) and cellular proliferation markers (Ki-67 and CCND1) in KD + Bev tumors compared to the other groups. These results suggested that KD combined with Bev may be a useful treatment strategy for patients with GBM.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Dieta Cetogênica , Glioblastoma/terapia , Aminoácidos/metabolismo , Animais , Ciclo do Ácido Cítrico , Terapia Combinada , Dieta Cetogênica/métodos , Modelos Animais de Doenças , Cromatografia Gasosa-Espectrometria de Massas , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Glicólise , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Análise de SobrevidaRESUMO
BACKGROUND: Isocitrate dehydrogenase (IDH)-mutant tumors exhibit an altered metabolic state and are critically dependent upon nicotinamide adenine dinucleotide (NAD+) for cellular survival. NAD+ steady-state levels can be influenced by both biosynthetic and consumptive processes. Here, we investigated activation of sirtuin (SIRT) enzymes, which consume NAD+ as a coenzyme, as a potential mechanism to reduce cellular NAD+ levels in these tumors. METHODS: The effect of inhibition or activation of sirtuin activity, using (i) small molecules, (ii) clustered regularly interspaced short palindromic repeat/CRISPR associated protein 9 gene editing, and (iii) inducible overexpression, was investigated in IDH-mutant tumor lines, including patient-derived IDH-mutant glioma lines. RESULTS: We found that Sirt1 activation led to marked augmentation of NAD+ depletion and accentuation of cytotoxicity when combined with inhibition of nicotinamide phosphoribosyltransferase (NAMPT), consistent with the enzymatic activity of SIRT1 as a primary cellular NAD+ consumer in IDH-mutant cells. Activation of Sirt1 through either genetic overexpression or pharmacologic Sirt1-activating compounds (STACs), an existing class of well-tolerated drugs, led to inhibition of IDH1-mutant tumor cell growth. CONCLUSIONS: Activation of Sirt1 can selectively target IDH-mutant tumors. These findings indicate that relatively nontoxic STACs, administered either alone or in combination with NAMPT inhibition, could alter the growth trajectory of IDH-mutant gliomas while minimizing toxicity associated with cytotoxic chemotherapeutic regimens.
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Glioma , Sirtuínas , Citocinas , Glioma/tratamento farmacológico , Glioma/genética , Humanos , Isocitrato Desidrogenase/genética , NAD , Sirtuína 1RESUMO
The aggressive primary brain tumor glioblastoma (GBM) is characterized by aberrant metabolism that fuels its malignant phenotype. Diverse genetic subtypes of malignant glioma are sensitive to selective inhibition of the NAD+ salvage pathway enzyme nicotinamide phosphoribosyltransferase (NAMPT). However, the potential impact of NAD+ depletion on the brain tumor microenvironment has not been elaborated. In addition, systemic toxicity of NAMPT inhibition remains a significant concern. Here we show that microparticle-mediated intratumoral delivery of NAMPT inhibitor GMX1778 induces specific immunologic changes in the tumor microenvironment of murine GBM, characterized by upregulation of immune checkpoint PD-L1, recruitment of CD3+, CD4+, and CD8+ T cells, and reduction of M2-polarized immunosuppressive macrophages. NAD+ depletion and autophagy induced by NAMPT inhibitors mediated the upregulation of PD-L1 transcripts and cell surface protein levels in GBM cells. NAMPT inhibitor modulation of the tumor immune microenvironment was therefore combined with PD-1 checkpoint blockade in vivo, significantly increasing the survival of GBM-bearing animals. Thus, the therapeutic impacts of NAMPT inhibition extended beyond neoplastic cells, shaping surrounding immune effectors. Microparticle delivery and release of NAMPT inhibitor at the tumor site offers a safe and robust means to alter an immune tumor microenvironment that could potentiate checkpoint immunotherapy for glioblastoma. SIGNIFICANCE: Microparticle-mediated local inhibition of NAMPT modulates the tumor immune microenvironment and acts cooperatively with anti-PD-1 checkpoint blockade, offering a combination immunotherapy strategy for the treatment of GBM.
Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Encefálicas/terapia , Cianetos/administração & dosagem , Citocinas/antagonistas & inibidores , Glioblastoma/terapia , Guanidinas/administração & dosagem , NAD/efeitos dos fármacos , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Microambiente Tumoral/efeitos dos fármacos , Acrilamidas/administração & dosagem , Animais , Autofagia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Movimento Celular , Cianetos/efeitos adversos , Preparações de Ação Retardada , Portadores de Fármacos/síntese química , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Guanidinas/efeitos adversos , Humanos , Injeções Intralesionais , Macrófagos/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Camundongos , NAD/análise , NAD/deficiência , Piperidinas/administração & dosagem , Polímeros/síntese química , RNA Mensageiro/metabolismo , Transdução de Sinais , Microambiente Tumoral/imunologia , Regulação para Cima/efeitos dos fármacosRESUMO
The metabolic gene isocitrate dehydrogenase 1 (IDH1) is commonly mutated in lower grade glioma (LGG) and secondary glioblastoma (GBM). Regulatory T cells (Tregs) play a significant role in the suppression of antitumor immunity in human glioma. Given the importance of Tregs in the overall framework of designing immune-based therapies, a better understanding on their association with IDH mutational status remains of critical clinical importance. Using multispectral imaging analysis, we compared the incidence of Tregs in IDH-mutant and IDH wild-type glioma from patient tumor samples of LGG. An orthotopic IDH-mutant murine model was generated to evaluate the role of mutant IDH on Treg infiltration by immunohistochemistry. When compared to IDH wild-type controls, Tregs are disproportionally underrepresented in mutant disease, even when taken as a proportion of all infiltrating T cells. Our findings suggest that therapeutic agents targeting Tregs may be more appropriate in modulating the immune response to wild-type disease.
Assuntos
Neoplasias Encefálicas , Glioma , Animais , Neoplasias Encefálicas/genética , Glioma/genética , Humanos , Isocitrato Desidrogenase/genética , Camundongos , Mutação , Linfócitos T ReguladoresRESUMO
NAD+ is an essential cofactor metabolite and is the currency of metabolic transactions critical for cell survival. Depending on tissue context and genotype, cancer cells have unique dependencies on NAD+ metabolic pathways. PARPs catalyze oligomerization of NAD+ monomers into PAR chains during cellular response to alkylating chemotherapeutics, including procarbazine or temozolomide. Here we find that, in endogenous IDH1-mutant tumor models, alkylator-induced cytotoxicity is markedly augmented by pharmacologic inhibition or genetic knockout of the PAR breakdown enzyme PAR glycohydrolase (PARG). Both in vitro and in vivo, we observe that concurrent alkylator and PARG inhibition depletes freely available NAD+ by preventing PAR breakdown, resulting in NAD+ sequestration and collapse of metabolic homeostasis. This effect reversed with NAD+ rescue supplementation, confirming the mechanistic basis of cytotoxicity. Thus, alkylating chemotherapy exposes a genotype-specific metabolic weakness in tumor cells that can be exploited by PARG inactivation. SIGNIFICANCE: Oncogenic mutations in the isocitrate dehydrogenase genes IDH1 or IDH2 initiate diffuse gliomas of younger adulthood. Strategies to maximize the effectiveness of chemotherapy in these tumors are needed. We discover alkylating chemotherapy and concurrent PARG inhibition exploits an intrinsic metabolic weakness within these cancer cells to provide genotype-specific benefit.See related commentary by Pirozzi and Yan, p. 1629.This article is highlighted in the In This Issue feature, p. 1611.
Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Glicosídeo Hidrolases/metabolismo , NAD/metabolismo , Humanos , Células Tumorais CultivadasRESUMO
BACKGROUND: Few studies have examined the usefulness of intraoperative magnetic resonance spectroscopy (iMRS) for identifying abnormal signals at the resection margin during glioma surgery. The aim of this study was to assess the value of iMRS for detecting proliferative remnants of glioma at the resection margin. METHODS: Fifteen patients with newly diagnosed glioma underwent single-voxel 3-T iMRS concurrently with intraoperative magnetic resonance imaging-assisted surgery. Volumes of interest (VOIs) were placed at T2-hyperintense or contrast-enhancing lesions at the resection margin. In addition to technical verification, the correlation between the MIB-1 labeling index (a pathologic feature) and metabolites measured using iMRS (N-acetyl-L-aspartate [NAA], choline [Cho], and Cho/NAA ratio) was analyzed. RESULTS: iMRS was performed for 20 VOIs in 15 patients. Fourteen (70%) of these VOIs were confirmed to be MIB-1-positive. There was a significant positive correlation between the Cho/NAA ratio and MIB-1 index (r = 0.46, P = 0.04). Cho level (P = 0.003) and Cho/NAA ratio (P = 0.002) were significantly higher in VOIs that were MIB-1-positive than in those that were MIB-1-negative. Detection of a Cho level >1.074 mM and a Cho/NAA ratio >0.48 using iMRS resulted in high diagnostic accuracy for MIB-1-positive remnants (Cho level: sensitivity 86%, specificity 100%; Cho/NAA ratio: sensitivity 79%, specificity 100%). CONCLUSIONS: This study provides evidence that 3-T iMRS can detect proliferative remnants of glioma at the resection margin using the Cho level and Cho/NAA ratio, suggesting that intraoperative magnetic resonance imaging-assisted surgery with iMRS would be practicable in glioma.
Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Glioma/patologia , Glioma/cirurgia , Espectroscopia de Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Encéfalo/cirurgia , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: Emergence of mismatch repair (MMR) deficiency is a frequent mechanism of acquired resistance to the alkylating chemotherapeutic temozolomide (TMZ) in gliomas. Poly(ADP-ribose) polymerase inhibitors (PARPi) have been shown to potentiate TMZ cytotoxicity in several cancer types, including gliomas. We tested whether PARP inhibition could re-sensitize MSH6-null MMR-deficient gliomas to TMZ, and assessed the role of the base excision repair (BER) DNA damage repair pathway in PARPi-mediated effects. EXPERIMENTAL DESIGN: Isogenic pairs of MSH6 wild-type and MSH6-inactivated human glioblastoma (GBM) cells (including both IDH1/2 wild-type and IDH1 mutant), as well as MSH6-null cells derived from a patient with recurrent GBM were treated with TMZ, the PARPi veliparib or olaparib, and combination thereof. Efficacy of PARPi combined with TMZ was assessed in vivo. We used genetic and pharmacological approaches to dissect the contribution of BER. RESULTS: While having no detectable effect in MSH6 wild-type GBMs, PARPi selectively restored TMZ sensitivity in MSH6-deficient GBM cells. This genotype-specific restoration of activity translated in vivo, where combination treatment of veliparib and TMZ showed potent suppression of tumor growth of MSH6-inactivated orthotopic xenografts, compared with TMZ monotherapy. Unlike PARPi, genetic and pharmacological blockage of BER pathway did not re-sensitize MSH6-inactivated GBM cells to TMZ. Similarly, CRISPR PARP1 knockout did not re-sensitize MSH6-inactivated GBM cells to TMZ. CONCLUSIONS: PARPi restoration of TMZ chemosensitivity in MSH6-inactivated glioma represents a promising strategy to overcome acquired chemoresistance caused by MMR deficiency. Mechanistically, this PARPi-mediated synthetic phenotype was independent of BER blockage and was not recapitulated by loss of PARP1.