RESUMO
Glioma contains malignant cells in diverse states. Here, we combine spatial transcriptomics, spatial proteomics, and computational approaches to define glioma cellular states and uncover their organization. We find three prominent modes of organization. First, gliomas are composed of small local environments, each typically enriched with one major cellular state. Second, specific pairs of states preferentially reside in proximity across multiple scales. This pairing of states is consistent across tumors. Third, these pairwise interactions collectively define a global architecture composed of five layers. Hypoxia appears to drive the layers, as it is associated with a long-range organization that includes all cancer cell states. Accordingly, tumor regions distant from any hypoxic/necrotic foci and tumors that lack hypoxia such as low-grade IDH-mutant glioma are less organized. In summary, we provide a conceptual framework for the organization of cellular states in glioma, highlighting hypoxia as a long-range tissue organizer.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Análise Espacial , Transcriptoma/genética , Microambiente Tumoral , Proteômica , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Regulação Neoplásica da Expressão GênicaRESUMO
Glioblastoma multiforme (GBM) is an aggressive brain tumor for which current immunotherapy approaches have been unsuccessful. Here, we explore the mechanisms underlying immune evasion in GBM. By serially transplanting GBM stem cells (GSCs) into immunocompetent hosts, we uncover an acquired capability of GSCs to escape immune clearance by establishing an enhanced immunosuppressive tumor microenvironment. Mechanistically, this is not elicited via genetic selection of tumor subclones, but through an epigenetic immunoediting process wherein stable transcriptional and epigenetic changes in GSCs are enforced following immune attack. These changes launch a myeloid-affiliated transcriptional program, which leads to increased recruitment of tumor-associated macrophages. Furthermore, we identify similar epigenetic and transcriptional signatures in human mesenchymal subtype GSCs. We conclude that epigenetic immunoediting may drive an acquired immune evasion program in the most aggressive mesenchymal GBM subtype by reshaping the tumor immune microenvironment.
Assuntos
Neoplasias Encefálicas/imunologia , Epigênese Genética , Glioblastoma/imunologia , Evasão da Resposta Imune/imunologia , Células Mieloides/imunologia , Células-Tronco Neoplásicas/imunologia , Microambiente Tumoral/imunologia , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Metilação de DNA , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células Mieloides/metabolismo , Células Mieloides/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Glioblastoma (GBM) tumors consist of multiple cell populations, including self-renewing glioblastoma stem cells (GSCs) and immunosuppressive microglia. Here we identified Kunitz-type protease inhibitor TFPI2 as a critical factor connecting these cell populations and their associated GBM hallmarks of stemness and immunosuppression. TFPI2 promotes GSC self-renewal and tumor growth via activation of the c-Jun N-terminal kinase-signal transducer and activator of transcription (STAT)3 pathway. Secreted TFPI2 interacts with its functional receptor CD51 on microglia to trigger the infiltration and immunosuppressive polarization of microglia through activation of STAT6 signaling. Inhibition of the TFPI2-CD51-STAT6 signaling axis activates T cells and synergizes with anti-PD1 therapy in GBM mouse models. In human GBM, TFPI2 correlates positively with stemness, microglia abundance, immunosuppression and poor prognosis. Our study identifies a function for TFPI2 and supports therapeutic targeting of TFPI2 as an effective strategy for GBM.
Assuntos
Glioblastoma , Animais , Camundongos , Humanos , Glioblastoma/metabolismo , Inibidores de Proteases/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Microambiente Tumoral , Transdução de Sinais , Proteínas de Transporte/metabolismo , Imunossupressores/farmacologia , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/metabolismoRESUMO
Glioblastomas exhibit vast inter- and intra-tumoral heterogeneity, complicating the development of effective therapeutic strategies. Current in vitro models are limited in preserving the cellular and mutational diversity of parental tumors and require a prolonged generation time. Here, we report methods for generating and biobanking patient-derived glioblastoma organoids (GBOs) that recapitulate the histological features, cellular diversity, gene expression, and mutational profiles of their corresponding parental tumors. GBOs can be generated quickly with high reliability and exhibit rapid, aggressive infiltration when transplanted into adult rodent brains. We further demonstrate the utility of GBOs to test personalized therapies by correlating GBO mutational profiles with responses to specific drugs and by modeling chimeric antigen receptor T cell immunotherapy. Our studies show that GBOs maintain many key features of glioblastomas and can be rapidly deployed to investigate patient-specific treatment strategies. Additionally, our live biobank establishes a rich resource for basic and translational glioblastoma research.
Assuntos
Técnicas de Cultura de Células/métodos , Glioblastoma/metabolismo , Organoides/crescimento & desenvolvimento , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Bancos de Espécimes Biológicos , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Modelos Biológicos , Organoides/metabolismo , Reprodutibilidade dos Testes , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Glioblastoma (GBM) is an incurable primary malignant brain cancer hallmarked with a substantial protumorigenic immune component. Knowledge of the GBM immune microenvironment during tumor evolution and standard of care treatments is limited. Using single-cell transcriptomics and flow cytometry, we unveiled large-scale comprehensive longitudinal changes in immune cell composition throughout tumor progression in an epidermal growth factor receptor-driven genetic mouse GBM model. We identified subsets of proinflammatory microglia in developing GBMs and anti-inflammatory macrophages and protumorigenic myeloid-derived suppressors cells in end-stage tumors, an evolution that parallels breakdown of the blood-brain barrier and extensive growth of epidermal growth factor receptor+ GBM cells. A similar relationship was found between microglia and macrophages in patient biopsies of low-grade glioma and GBM. Temozolomide decreased the accumulation of myeloid-derived suppressor cells, whereas concomitant temozolomide irradiation increased intratumoral GranzymeB+ CD8+T cells but also increased CD4+ regulatory T cells. These results provide a comprehensive and unbiased immune cellular landscape and its evolutionary changes during GBM progression.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Animais , Neoplasias Encefálicas/metabolismo , Receptores ErbB , Glioblastoma/metabolismo , Humanos , Camundongos , Análise de Sequência de RNA , Análise de Célula Única , Temozolomida/uso terapêutico , Microambiente Tumoral/genéticaRESUMO
The anatomic location and immunologic characteristics of brain tumors result in strong lymphocyte suppression. Consequently, conventional immunotherapies targeting CD8 T cells are ineffective against brain tumors. Tumor cells escape immunosurveillance by various mechanisms and tumor cell metabolism can affect the metabolic states and functions of tumor-infiltrating lymphocytes. Here, we discovered that brain tumor cells had a particularly high demand for oxygen, which affected γδ T cell-mediated antitumor immune responses but not those of conventional T cells. Specifically, tumor hypoxia activated the γδ T cell protein kinase A pathway at a transcriptional level, resulting in repression of the activatory receptor NKG2D. Alleviating tumor hypoxia reinvigorated NKG2D expression and the antitumor function of γδ T cells. These results reveal a hypoxia-mediated mechanism through which brain tumors and γδ T cells interact and emphasize the importance of γδ T cells for antitumor immunity against brain tumors.
Assuntos
Neoplasias Encefálicas/imunologia , Citotoxicidade Imunológica , Glioblastoma/imunologia , Linfócitos Intraepiteliais/imunologia , Linfócitos do Interstício Tumoral/imunologia , Evasão Tumoral , Microambiente Tumoral , Animais , Apoptose , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Antígenos CD8/genética , Antígenos CD8/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Codificadores da Cadeia delta de Receptores de Linfócitos T , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Linfócitos Intraepiteliais/metabolismo , Linfócitos Intraepiteliais/patologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos Nus , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Fenótipo , Transdução de Sinais , Hipóxia TumoralRESUMO
Immunosuppressive macrophages restrict anti-cancer immunity in glioblastoma (GBM). Here, we studied the contribution of microglia (MGs) and monocyte-derived macrophages (MDMs) to immunosuppression and mechanisms underlying their regulatory function. MDMs outnumbered MGs at late tumor stages and suppressed T cell activity. Molecular and functional analysis identified a population of glycolytic MDM expressing GLUT1 with potent immunosuppressive activity. GBM-derived factors promoted high glycolysis, lactate, and interleukin-10 (IL-10) production in MDMs. Inhibition of glycolysis or lactate production in MDMs impaired IL-10 expression and T cell suppression. Mechanistically, intracellular lactate-driven histone lactylation promoted IL-10 expression, which was required to suppress T cell activity. GLUT1 expression on MDMs was induced downstream of tumor-derived factors that activated the PERK-ATF4 axis. PERK deletion in MDM abrogated histone lactylation, led to the accumulation of intratumoral T cells and tumor growth delay, and, in combination with immunotherapy, blocked GBM progression. Thus, PERK-driven glucose metabolism promotes MDM immunosuppressive activity via histone lactylation.
Assuntos
Glioblastoma , Glucose , Histonas , Macrófagos , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Animais , Histonas/metabolismo , Camundongos , Macrófagos/imunologia , Macrófagos/metabolismo , Glucose/metabolismo , Humanos , Linhagem Celular Tumoral , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/genética , Interleucina-10/metabolismo , Glicólise , Microglia/metabolismo , Microglia/imunologia , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia , Linfócitos T/metabolismo , Tolerância ImunológicaRESUMO
Low-grade gliomas almost invariably progress into secondary glioblastoma (sGBM) with limited therapeutic option and poorly understood mechanism. By studying the mutational landscape of 188 sGBMs, we find significant enrichment of TP53 mutations, somatic hypermutation, MET-exon-14-skipping (METex14), PTPRZ1-MET (ZM) fusions, and MET amplification. Strikingly, METex14 frequently co-occurs with ZM fusion and is present in â¼14% of cases with significantly worse prognosis. Subsequent studies show that METex14 promotes glioma progression by prolonging MET activity. Furthermore, we describe a MET kinase inhibitor, PLB-1001, that demonstrates remarkable potency in selectively inhibiting MET-altered tumor cells in preclinical models. Importantly, this compound also shows blood-brain barrier permeability and is subsequently applied in a phase I clinical trial that enrolls MET-altered chemo-resistant glioma patients. Encouragingly, PLB-1001 achieves partial response in at least two advanced sGBM patients with rarely significant side effects, underscoring the clinical potential for precisely treating gliomas using this therapy.
Assuntos
Neoplasias Encefálicas , Éxons , Glioblastoma , Mutação , Inibidores de Proteínas Quinases , Proteínas Proto-Oncogênicas c-met , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Sistemas de Liberação de Medicamentos , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Ratos Sprague-Dawley , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Genetic drivers of cancer can be dysregulated through epigenetic modifications of DNA. Although the critical role of DNA 5-methylcytosine (5mC) in the regulation of transcription is recognized, the functions of other non-canonical DNA modifications remain obscure. Here, we report the identification of novel N6-methyladenine (N6-mA) DNA modifications in human tissues and implicate this epigenetic mark in human disease, specifically the highly malignant brain cancer glioblastoma. Glioblastoma markedly upregulated N6-mA levels, which co-localized with heterochromatic histone modifications, predominantly H3K9me3. N6-mA levels were dynamically regulated by the DNA demethylase ALKBH1, depletion of which led to transcriptional silencing of oncogenic pathways through decreasing chromatin accessibility. Targeting the N6-mA regulator ALKBH1 in patient-derived human glioblastoma models inhibited tumor cell proliferation and extended the survival of tumor-bearing mice, supporting this novel DNA modification as a potential therapeutic target for glioblastoma. Collectively, our results uncover a novel epigenetic node in cancer through the DNA modification N6-mA.
Assuntos
Adenina/análogos & derivados , Neoplasias Encefálicas/patologia , Metilação de DNA , Glioblastoma/patologia , Adenina/análise , Adenina/química , Adulto , Idoso , Homólogo AlkB 1 da Histona H2a Dioxigenase/antagonistas & inibidores , Homólogo AlkB 1 da Histona H2a Dioxigenase/genética , Homólogo AlkB 1 da Histona H2a Dioxigenase/metabolismo , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Hipóxia Celular , Criança , Epigenômica , Feminino , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Heterocromatina/metabolismo , Histonas/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
The limited efficacy of immunotherapies against glioblastoma underscores the urgency of better understanding immunity in the central nervous system. We found that treatment with αCTLA-4, but not αPD-1, prolonged survival in a mouse model of mesenchymal-like glioblastoma. This effect was lost upon the depletion of CD4+ T cells but not CD8+ T cells. αCTLA-4 treatment increased frequencies of intratumoral IFNγ-producing CD4+ T cells, and IFNγ blockade negated the therapeutic impact of αCTLA-4. The anti-tumor activity of CD4+ T cells did not require tumor-intrinsic MHC-II expression but rather required conventional dendritic cells as well as MHC-II expression on microglia. CD4+ T cells interacted directly with microglia, promoting IFNγ-dependent microglia activation and phagocytosis via the AXL/MER tyrosine kinase receptors, which were necessary for tumor suppression. Thus, αCTLA-4 blockade in mesenchymal-like glioblastoma promotes a CD4+ T cell-microglia circuit wherein IFNγ triggers microglia activation and phagocytosis and microglia in turn act as antigen-presenting cells fueling the CD4+ T cell response.
Assuntos
Glioblastoma , Camundongos , Animais , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Antígeno CTLA-4 , Células Th1 , Microglia , Linfócitos T CD8-Positivos , Fagocitose , Células Dendríticas , Linfócitos T CD4-PositivosRESUMO
Angiogenin (ANG) is a secreted ribonuclease (RNase) with cell-type- and context-specific roles in growth, survival, and regeneration. Although these functions require receptor-mediated endocytosis and appropriate subcellular localization, the identity of the cell surface receptor remains undefined. Here, we show that plexin-B2 (PLXNB2) is the functional receptor for ANG in endothelial, cancer, neuronal, and normal hematopoietic and leukemic stem and progenitor cells. Mechanistically, PLXNB2 mediates intracellular RNA processing that contribute to cell growth, survival, and regenerative capabilities of ANG. Antibodies generated against the ANG-binding site on PLXNB2 restricts ANG activity in vitro and in vivo, resulting in inhibition of established xenograft tumors, ANG-induced neurogenesis and neuroprotection, levels of pro-self-renewal transcripts in hematopoietic and patient-derived leukemic stem and progenitor cells, and reduced progression of leukemia in vivo. PLXNB2 is therefore required for the physiological and pathological functions of ANG and has significant therapeutic potential in solid and hematopoietic cancers and neurodegenerative diseases.
Assuntos
Proteínas do Tecido Nervoso/metabolismo , Ribonuclease Pancreático/metabolismo , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Células-Tronco Hematopoéticas/metabolismo , Xenoenxertos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neurogênese , Ribonuclease Pancreático/químicaRESUMO
In this issue, Lv et al.1 explore EGFR-driven epitranscriptomic reprogramming in glioblastoma, revealing the pivotal role of the EGFR-ALKBH5-GCLM axis in ferroptosis protection. Their findings offer mechanistic insight and therapeutic strategies involving novel combination targets to enhance tumor responses.
Assuntos
Neoplasias Encefálicas , Receptores ErbB , Glioblastoma , Humanos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismoRESUMO
Glioblastomas and brain metastases are highly proliferative brain tumors with short survival times. Previously, using (13)C-NMR analysis of brain tumors resected from patients during infusion of (13)C-glucose, we demonstrated that there is robust oxidation of glucose in the citric acid cycle, yet glucose contributes less than 50% of the carbons to the acetyl-CoA pool. Here, we show that primary and metastatic mouse orthotopic brain tumors have the capacity to oxidize [1,2-(13)C]acetate and can do so while simultaneously oxidizing [1,6-(13)C]glucose. The tumors do not oxidize [U-(13)C]glutamine. In vivo oxidation of [1,2-(13)C]acetate was validated in brain tumor patients and was correlated with expression of acetyl-CoA synthetase enzyme 2, ACSS2. Together, the data demonstrate a strikingly common metabolic phenotype in diverse brain tumors that includes the ability to oxidize acetate in the citric acid cycle. This adaptation may be important for meeting the high biosynthetic and bioenergetic demands of malignant growth.
Assuntos
Acetato-CoA Ligase/metabolismo , Acetatos/metabolismo , Neoplasias Encefálicas/metabolismo , Ciclo do Ácido Cítrico , Glioblastoma/metabolismo , Acetato-CoA Ligase/genética , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Modelos Animais de Doenças , Glioblastoma/patologia , Ácido Glutâmico/metabolismo , Humanos , Camundongos , Metástase Neoplásica/patologiaRESUMO
Developmental fate decisions are dictated by master transcription factors (TFs) that interact with cis-regulatory elements to direct transcriptional programs. Certain malignant tumors may also depend on cellular hierarchies reminiscent of normal development but superimposed on underlying genetic aberrations. In glioblastoma (GBM), a subset of stem-like tumor-propagating cells (TPCs) appears to drive tumor progression and underlie therapeutic resistance yet remain poorly understood. Here, we identify a core set of neurodevelopmental TFs (POU3F2, SOX2, SALL2, and OLIG2) essential for GBM propagation. These TFs coordinately bind and activate TPC-specific regulatory elements and are sufficient to fully reprogram differentiated GBM cells to "induced" TPCs, recapitulating the epigenetic landscape and phenotype of native TPCs. We reconstruct a network model that highlights critical interactions and identifies candidate therapeutic targets for eliminating TPCs. Our study establishes the epigenetic basis of a developmental hierarchy in GBM, provides detailed insight into underlying gene regulatory programs, and suggests attendant therapeutic strategies. PAPERCLIP:
Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/patologia , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Neoplasias Encefálicas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Células Cultivadas , Proteínas Correpressoras/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Fator de Transcrição 2 de Oligodendrócitos , Elementos Reguladores de Transcrição , Fatores de Transcrição/metabolismoRESUMO
Inhibition of the tumour suppressive function of p53 (encoded by TP53) is paramount for cancer development in humans. However, p53 remains unmutated in the majority of cases of glioblastoma (GBM)-the most common and deadly adult brain malignancy1,2. Thus, how p53-mediated tumour suppression is countered in TP53 wild-type (TP53WT) GBM is unknown. Here we describe a GBM-specific epigenetic mechanism in which the chromatin regulator bromodomain-containing protein 8 (BRD8) maintains H2AZ occupancy at p53 target loci through the EP400 histone acetyltransferase complex. This mechanism causes a repressive chromatin state that prevents transactivation by p53 and sustains proliferation. Notably, targeting the bromodomain of BRD8 displaces H2AZ, enhances chromatin accessibility and engages p53 transactivation. This in turn enforces cell cycle arrest and tumour suppression in TP53WT GBM. In line with these findings, BRD8 is highly expressed with H2AZ in proliferating single cells of patient-derived GBM, and is inversely correlated with CDKN1A, a canonical p53 target that encodes p21 (refs. 3,4). This work identifies BRD8 as a selective epigenetic vulnerability for a malignancy for which treatment has not improved for decades. Moreover, targeting the bromodomain of BRD8 may be a promising therapeutic strategy for patients with TP53WT GBM.
Assuntos
Epigênese Genética , Glioblastoma , Fatores de Transcrição , Proteína Supressora de Tumor p53 , Adulto , Humanos , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Histonas/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proliferação de CélulasRESUMO
Diffuse gliomas, particularly glioblastomas, are incurable brain tumours1. They are characterized by networks of interconnected brain tumour cells that communicate via Ca2+ transients2-6. However, the networks' architecture and communication strategy and how these influence tumour biology remain unknown. Here we describe how glioblastoma cell networks include a small, plastic population of highly active glioblastoma cells that display rhythmic Ca2+ oscillations and are particularly connected to others. Their autonomous periodic Ca2+ transients preceded Ca2+ transients of other network-connected cells, activating the frequency-dependent MAPK and NF-κB pathways. Mathematical network analysis revealed that glioblastoma network topology follows scale-free and small-world properties, with periodic tumour cells frequently located in network hubs. This network design enabled resistance against random damage but was vulnerable to losing its key hubs. Targeting of autonomous rhythmic activity by selective physical ablation of periodic tumour cells or by genetic or pharmacological interference with the potassium channel KCa3.1 (also known as IK1, SK4 or KCNN4) strongly compromised global network communication. This led to a marked reduction of tumour cell viability within the entire network, reduced tumour growth in mice and extended animal survival. The dependency of glioblastoma networks on periodic Ca2+ activity generates a vulnerability7 that can be exploited for the development of novel therapies, such as with KCa3.1-inhibiting drugs.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Camundongos , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , NF-kappa B/metabolismo , Sistema de Sinalização das MAP Quinases , Sinalização do Cálcio , Morte Celular , Análise de Sobrevida , Cálcio/metabolismoRESUMO
Gliomas synaptically integrate into neural circuits1,2. Previous research has demonstrated bidirectional interactions between neurons and glioma cells, with neuronal activity driving glioma growth1-4 and gliomas increasing neuronal excitability2,5-8. Here we sought to determine how glioma-induced neuronal changes influence neural circuits underlying cognition and whether these interactions influence patient survival. Using intracranial brain recordings during lexical retrieval language tasks in awake humans together with site-specific tumour tissue biopsies and cell biology experiments, we find that gliomas remodel functional neural circuitry such that task-relevant neural responses activate tumour-infiltrated cortex well beyond the cortical regions that are normally recruited in the healthy brain. Site-directed biopsies from regions within the tumour that exhibit high functional connectivity between the tumour and the rest of the brain are enriched for a glioblastoma subpopulation that exhibits a distinct synaptogenic and neuronotrophic phenotype. Tumour cells from functionally connected regions secrete the synaptogenic factor thrombospondin-1, which contributes to the differential neuron-glioma interactions observed in functionally connected tumour regions compared with tumour regions with less functional connectivity. Pharmacological inhibition of thrombospondin-1 using the FDA-approved drug gabapentin decreases glioblastoma proliferation. The degree of functional connectivity between glioblastoma and the normal brain negatively affects both patient survival and performance in language tasks. These data demonstrate that high-grade gliomas functionally remodel neural circuits in the human brain, which both promotes tumour progression and impairs cognition.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Vias Neurais , Humanos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Trombospondina 1/antagonistas & inibidores , Gabapentina/farmacologia , Gabapentina/uso terapêutico , Progressão da Doença , Cognição , Taxa de Sobrevida , Vigília , Biópsia , Proliferação de Células/efeitos dos fármacosRESUMO
Liu et al. (2021) demonstrate that CHKα2 is capable of promoting lipolysis of lipid droplets through mechanisms that require sequential steps of post-translational modifications after glucose deprivation. Intriguingly, the oxidation of fatty acids derived from lipid droplets is essential for the survival of tumor cells that informs clinical outcome among glioblastoma patients.
Assuntos
Glioblastoma , Lipólise , Ácidos Graxos/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Gotículas Lipídicas/metabolismo , OxirreduçãoRESUMO
Aberrant cell proliferation is a hallmark of cancer, including glioblastoma (GBM). Here we report that protein arginine methyltransferase (PRMT) 6 activity is required for the proliferation, stem-like properties, and tumorigenicity of glioblastoma stem cells (GSCs), a subpopulation in GBM critical for malignancy. We identified a casein kinase 2 (CK2)-PRMT6-regulator of chromatin condensation 1 (RCC1) signaling axis whose activity is an important contributor to the stem-like properties and tumor biology of GSCs. CK2 phosphorylates and stabilizes PRMT6 through deubiquitylation, which promotes PRMT6 methylation of RCC1, which in turn is required for RCC1 association with chromatin and activation of RAN. Disruption of this pathway results in defects in mitosis. EPZ020411, a specific small-molecule inhibitor for PRMT6, suppresses RCC1 arginine methylation and improves the cytotoxic activity of radiotherapy against GSC brain tumor xenografts. This study identifies a CK2α-PRMT6-RCC1 signaling axis that can be therapeutically targeted in the treatment of GBM.
Assuntos
Neoplasias Encefálicas , Carcinogênese , Proteínas de Ciclo Celular , Glioblastoma , Fatores de Troca do Nucleotídeo Guanina , Mitose/efeitos da radiação , Proteínas de Neoplasias , Proteínas Nucleares , Proteína-Arginina N-Metiltransferases , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/efeitos da radiação , Caseína Quinase II/genética , Caseína Quinase II/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Feminino , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/radioterapia , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos , Mitose/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Necrosis in solid tumors is commonly associated with poor prognostic but how these lesions expand remains unclear. Studies have found that neutrophils associate with and contribute to necrosis development in glioblastoma by inducing tumor cell ferroptosis through transferring myeloperoxidase-containing granules. However, the mechanism of neutrophilic granule transfer remains elusive. We performed an unbiased small molecule screen and found that statins inhibit neutrophil-induced tumor cell death by blocking the neutrophilic granule transfer. Further, we identified a novel process wherein neutrophils are engulfed by tumor cells before releasing myeloperoxidase-containing contents into tumor cells. This neutrophil engulfment is initiated by integrin-mediated adhesion, and further mediated by LC3-associated phagocytosis (LAP), which can be blocked by inhibiting the Vps34-UVRAG-RUBCN-containing PI3K complex. Myeloperoxidase inhibition or Vps34 depletion resulted in reduced necrosis formation and prolonged mouse survival in an orthotopic glioblastoma mouse model. Thus, our study unveils a critical role for LAP-mediated neutrophil internalization in facilitating the transfer of neutrophilic granules, which in turn triggers tumor cell death and necrosis expansion. Targeting this process holds promise for improving glioblastoma prognosis.