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1.
Sci Rep ; 14(1): 16721, 2024 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030304

RESUMO

Antigen-specific cytotoxic CD8 T cells are extremely effective in controlling tumor growth and have been the focus of immunotherapy approaches. We leverage in silico tools to investigate whether the occurrence of mutations in proteins previously described as immunogenic and highly expressed by glioblastoma multiforme (GBM), such as Epidermal Growth Factor Receptor (EGFR), Isocitrate Dehydrogenase 1 (IDH1), Phosphatase and Tensin homolog (PTEN) and Tumor Protein 53 (TP53), may be contributing to the differential presentation of immunogenic epitopes. We recovered Class I MHC binding information from wild-type and mutated proteins using the Immune Epitope Database (IEDB). After that, we built peptide-MHC (pMHC-I) models in HLA-arena, followed by hierarchical clustering analysis based on electrostatic surface features from each complex. We identified point mutations that are determinants for the presentation of a set of peptides from TP53 protein. We point to structural features in the pMHC-I complexes of wild-type and mutated peptides, which may play a role in the recognition of CD8 T cells. To further explore these features, we performed 100 ns molecular dynamics simulations for the peptide pairs (wt/mut) selected. In pursuit of novel therapeutic targets for GBM treatment, we selected peptides where our predictive results indicated that mutations would not disrupt epitope presentation, thereby maintaining a specific CD8 T cell immune response. These peptides hold potential for future GBM interventions, including peptide-based or mRNA vaccine development applications.


Assuntos
Apresentação de Antígeno , Linfócitos T CD8-Positivos , Glioblastoma , Isocitrato Desidrogenase , Proteína Supressora de Tumor p53 , Glioblastoma/imunologia , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Linfócitos T CD8-Positivos/imunologia , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/imunologia , Isocitrato Desidrogenase/química , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/imunologia , Apresentação de Antígeno/imunologia , Mutação , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/imunologia , PTEN Fosfo-Hidrolase/química , Receptores ErbB/imunologia , Receptores ErbB/genética , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia
2.
Braz J Med Biol Res ; 57: e13961, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985083

RESUMO

Glioblastomas are known for their poor clinical prognosis, with recurrent tumors often exhibiting greater invasiveness and faster growth rates compared to primary tumors. To understand the intratumoral changes driving this phenomenon, we employed single-cell sequencing to analyze the differences between two pairs of primary and recurrent glioblastomas. Our findings revealed an upregulation of ferroptosis in endothelial cells within recurrent tumors, identified by the significant overexpression of the NOX4 gene. Further analysis indicated that knocking down NOX4 in endothelial cells reduced the activity of the ferroptosis pathway. Utilizing conditioned media from endothelial cells with lower ferroptosis activity, we observed a decrease in the growth rate of glioblastoma cells. These results highlighted the complex role of ferroptosis within tumors and suggested that targeting ferroptosis in the treatment of glioblastomas requires careful consideration of its effects on endothelial cells, as it may otherwise produce counterproductive outcomes.


Assuntos
Neoplasias Encefálicas , Células Endoteliais , Ferroptose , Glioblastoma , Isocitrato Desidrogenase , Recidiva Local de Neoplasia , Humanos , Glioblastoma/patologia , Glioblastoma/genética , Ferroptose/genética , Ferroptose/fisiologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Isocitrato Desidrogenase/genética , Células Endoteliais/patologia , Linhagem Celular Tumoral , Proliferação de Células
3.
Biol Res ; 57(1): 30, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760850

RESUMO

BACKGROUND: Mutations in isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2), are present in most gliomas. IDH1 mutation is an important prognostic marker in glioma. However, its regulatory mechanism in glioma remains incompletely understood. RESULTS: miR-182-5p expression was increased within IDH1-mutant glioma specimens according to TCGA, CGGA, and online dataset GSE119740, as well as collected clinical samples. (R)-2-hydroxyglutarate ((R)-2HG) treatment up-regulated the expression of miR-182-5p, enhanced glioma cell proliferation, and suppressed apoptosis; miR-182-5p inhibition partially eliminated the oncogenic effects of R-2HG upon glioma cells. By direct binding to Cyclin Dependent Kinase Inhibitor 2 C (CDKN2C) 3'UTR, miR-182-5p inhibited CDKN2C expression. Regarding cellular functions, CDKN2C knockdown promoted R-2HG-treated glioma cell viability, suppressed apoptosis, and relieved cell cycle arrest. Furthermore, CDKN2C knockdown partially attenuated the effects of miR-182-5p inhibition on cell phenotypes. Moreover, CDKN2C knockdown exerted opposite effects on cell cycle check point and apoptosis markers to those of miR-182-5p inhibition; also, CDKN2C knockdown partially attenuated the functions of miR-182-5p inhibition in cell cycle check point and apoptosis markers. The engineered CS-NPs (antagomir-182-5p) effectively encapsulated and delivered antagomir-182-5p, enhancing anti-tumor efficacy in vivo, indicating the therapeutic potential of CS-NPs(antagomir-182-5p) in targeting the miR-182-5p/CDKN2C axis against R-2HG-driven oncogenesis in mice models. CONCLUSIONS: These insights highlight the potential of CS-NPs(antagomir-182-5p) to target the miR-182-5p/CDKN2C axis, offering a promising therapeutic avenue against R-2HG's oncogenic influence to glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Isocitrato Desidrogenase , MicroRNAs , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Glioma/genética , Glioma/metabolismo , Animais , Camundongos , Xenoenxertos , Transplante de Neoplasias , Neoplasias Encefálicas/genética , MicroRNAs/metabolismo
5.
Purinergic Signal ; 20(1): 47-64, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36964277

RESUMO

Malignant gliomas are highly heterogeneous glia-derived tumors that present an aggressive and invasive nature, with a dismal prognosis. The multi-dimensional interactions between glioma cells and other tumor microenvironment (TME) non-tumoral components constitute a challenge to finding successful treatment strategies. Several molecules, such as extracellular purines, participate in signaling events and support the immunosuppressive TME of glioma patients. The purinergic signaling and the ectoenzymes network involved in the metabolism of these extracellular nucleotides are still unexplored in the glioma TME, especially in lower-grade gliomas (LGG). Also, differences between IDH-mutant (IDH-Mut) versus wild-type (IDH-WT) gliomas are still unknown in this context. For the first time, to our knowledge, this study characterizes the TME of LGG, high-grade gliomas (HGG) IDH-Mut, and HGG IDH-WT patients regarding purinergic ectoenzymes and P1 receptors, focusing on tumor-infiltrating lymphocytes. Here, we show that ectoenzymes from both canonical and non-canonical pathways are increased in the TME when compared to the peripheral blood. We hypothesize this enhancement supports extracellular adenosine generation, hence increasing TME immunosuppression.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/patologia , Linfócitos do Interstício Tumoral/patologia , Isocitrato Desidrogenase/genética , Glioma/patologia , Prognóstico , Mutação , Microambiente Tumoral
6.
Cancer Res ; 84(5): 741-756, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38117484

RESUMO

Tumor adaptation or selection is thought to underlie therapy resistance in glioma. To investigate longitudinal epigenetic evolution of gliomas in response to therapeutic pressure, we performed an epigenomic analysis of 132 matched initial and recurrent tumors from patients with IDH-wildtype (IDHwt) and IDH-mutant (IDHmut) glioma. IDHwt gliomas showed a stable epigenome over time with relatively low levels of global methylation. The epigenome of IDHmut gliomas showed initial high levels of genome-wide DNA methylation that was progressively reduced to levels similar to those of IDHwt tumors. Integration of epigenomics, gene expression, and functional genomics identified HOXD13 as a master regulator of IDHmut astrocytoma evolution. Furthermore, relapse of IDHmut tumors was accompanied by histologic progression that was associated with survival, as validated in an independent cohort. Finally, the initial cell composition of the tumor microenvironment varied between IDHwt and IDHmut tumors and changed differentially following treatment, suggesting increased neoangiogenesis and T-cell infiltration upon treatment of IDHmut gliomas. This study provides one of the largest cohorts of paired longitudinal glioma samples with epigenomic, transcriptomic, and genomic profiling and suggests that treatment of IDHmut glioma is associated with epigenomic evolution toward an IDHwt-like phenotype. SIGNIFICANCE: Standard treatments are related to loss of DNA methylation in IDHmut glioma, resulting in epigenetic activation of genes associated with tumor progression and alterations in the microenvironment that resemble treatment-naïve IDHwt glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Isocitrato Desidrogenase , Humanos , Neoplasias Encefálicas/patologia , Epigênese Genética , Epigenômica , Glioma/patologia , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Mutação , Recidiva Local de Neoplasia/genética , Microambiente Tumoral
7.
J Neurol Sci ; 452: 120762, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37562166

RESUMO

Diffuse gliomas are tumors that arise from glial or glial progenitor cells. They are currently classified as astrocytoma isocitrate dehydrogenase (IDH)-mutant or oligodendroglioma IDH-mutant, and 1p/19q-codeleted, both slower-growing tumors, or glioblastoma (GBM), a more aggressive tumor. Despite advances in the diagnosis and treatment of gliomas, the median survival time after diagnosis of GBM remains low, approximately 15 months, with a 5-year overall survival rate of only 6.8%. Therefore, new biomarkers that could support the earlier diagnosis and prognosis of these tumors would be of great value. MUC17, a membrane-bound mucin, has been identified as a potential biomarker for several tumors. However, the role of this mucin in adult gliomas has not yet been explored. Here, we show for the first time, in a retrospective study and by in silico analysis that MUC17 is one of the relevant mutant genes in adult gliomas. Moreover, that an increase in MUC17 methylation correlates with an increase in glioma malignancy grade. Patients with MUC17 mutations had a poorer prognosis than their wild-type counterparts in both GBM and non-GBM glioma cohorts. We also analyzed mutational profiles that correlated strongly with poor survival. Therefore, in this study, we present a new potential biomarker for further investigation, especially for the prognosis of adult diffuse gliomas.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Adulto , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Metilação , Estudos Retrospectivos , Glioma/diagnóstico , Glioma/genética , Glioma/patologia , Mutação/genética , Prognóstico , Mucinas/genética , Isocitrato Desidrogenase/genética
8.
Clinics (Sao Paulo) ; 78: 100238, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37354775

RESUMO

OBJECTIVE: To investigate the value of a nomogram based on multiparametric and multiregional MR images to predict Isocitrate Dehydrogenase-1 (IDH1) gene mutations in glioma. DATA AND METHODS: The authors performed a retrospective analysis of 110 MR images of surgically confirmed pathological gliomas; 33 patients with IDH1 gene Mutation (IDH1-M) and 77 patients with Wild-type IDH1 (IDH1-W) were divided into training and validation sets in a 7:3 ratio. The clinical features were statistically analyzed using SPSS and R software. Three glioma regions (rCET, rE, rNEC) were outlined using ITK-SNAP software and projected to four conventional sequences (T1, T2, Flair, T1C) for feature extraction using AI-Kit software. The extracted features were screened using R software. A logistic regression model was established, and a nomogram was generated using the selected clinical features. Eight models were developed based on different sequences and ROIs, and Receiver Operating Characteristic (ROC) curves were used to evaluate the predictive efficacy. Decision curve analysis was performed to assess the clinical usefulness. RESULTS: Age was selected with Radscore to construct the nomogram. The Model 1 AUC values based on four sequences and three ROIs were the highest in these models, at 0.93 and 0.89, respectively. Decision curve analysis indicated that the net benefit of model 1 was higher than that of the other models for most Pt-values. CONCLUSION: A nomogram based on multiparametric and multiregional MR images can predict the mutation status of the IDH1 gene accurately.


Assuntos
Glioma , Nomogramas , Humanos , Estudos Retrospectivos , Glioma/diagnóstico por imagem , Glioma/genética , Curva ROC , Mutação/genética , Imageamento por Ressonância Magnética/métodos , Isocitrato Desidrogenase/genética
9.
Gac Med Mex ; 159(2): 161-168, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37094238

RESUMO

In 2021, the latest version of the World Health Organization classification of central nervous system tumors (WHO CNS5) was published, which is considered an international standard. The first editions of this classification were based on histological characteristics and, subsequently, aspects related to new knowledge were incorporated. In the 2016 revision, molecular characteristics were implemented for the classification and staging of gliomas, such as the presence of mutations in IDH1 or IDH2. Currently, advanced magnetic resonance imaging (MRI) techniques allow assessing for the presence of 2-HG (increased oncometabolite that precedes IDH mutations), whereby IDH mutations can be indirectly identified, without invasive procedures being required. Advanced MRI is a growing field, highly useful for diagnosis and management of different pathologies. This document addresses the implications of WHO CNS5 classification in the evaluation of gliomas, as well as historical aspects, the bases of conventional MRI, and advanced MRI sequences useful in current classification.


En 2021 se publicó la última versión de la clasificación de tumores del sistema nervioso central de la Organización Mundial de la Salud (WHO CNS5 por sus siglas en inglés), considerada un estándar internacional. Las primeras ediciones se basaron en características histológicas y posteriormente se incorporaron aspectos relacionados con nuevos conocimientos. En la revisión de 2016 se implementaron características moleculares para la clasificación y estadificación de los gliomas, como la presencia de mutaciones en IDH1 y IDH2. Actualmente, las técnicas de resonancia magnética avanzada permiten valorar la presencia de 2-HG (oncometabolito incrementado ante mutaciones en IDH), de forma que indirectamente y sin procedimientos invasivos pueden identificarse las mutaciones en IDH. La resonancia magnética avanzada es un procedimiento aún en desarrollo, de gran utilidad para el diagnóstico y manejo de distintas patologías. En el presente documento se abordan las implicaciones de la WHO CNS5 en la evaluación de gliomas, así como aspectos históricos, las bases de la resonancia magnética convencional y secuencias de resonancia magnética avanzada útiles en la clasificación actual.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética , Biomarcadores , Mutação , Organização Mundial da Saúde
10.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36076905

RESUMO

Tumor cell infiltrative ability into surrounding brain tissue is a characteristic of diffusely infiltrative astrocytoma and is strongly associated with extracellular matrix (ECM) stiffness. Collagens are the most abundant ECM scaffolding proteins and contribute to matrix organization and stiffness. LOX family members, copper-dependent amine oxidases, participate in the collagen and elastin crosslinking that determine ECM tensile strength. Common IDH mutations in lower-grade gliomas (LGG) impact prognosis and have been associated with ECM stiffness. We analyzed the expression levels of LOX family members and matrisome-associated genes in astrocytoma stratified by malignancy grade and IDH mutation status. A progressive increase in expression of all five LOX family members according to malignancy grade was found. LOX, LOXL1, and LOXL3 expression correlated with matrisome gene expressions. LOXL1 correlations were detected in LGG with IDH mutation (IDHmut), LOXL3 correlations in LGG with IDH wild type (IDHwt) and strong LOX correlations in glioblastoma (GBM) were found. These increasing correlations may explain the increment of ECM stiffness and tumor aggressiveness from LGG-IDHmut and LGG-IDHwt through to GBM. The expression of the mechanosensitive transcription factor, ß-catenin, also increased with malignancy grade and was correlated with LOXL1 and LOXL3 expression, suggesting involvement of this factor in the outside-in signaling pathway.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Proteínas da Matriz Extracelular , Matriz Extracelular , Glioblastoma , Glioma , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Astrocitoma/genética , Neoplasias Encefálicas/metabolismo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Expressão Gênica , Glioblastoma/genética , Glioma/metabolismo , Humanos , Isocitrato Desidrogenase/genética , Mutação
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