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1.
Neurooncol Adv ; 5(1): vdad147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38024245

RESUMO

Background: Infiltration is a life-threatening growth pattern in malignant astrocytomas and a significant cause of therapy resistance. It results in the tumor cell spreading deeply into the surrounding brain tissue, fostering tumor recurrence and making complete surgical resection impossible. We need to thoroughly understand the mechanisms underlying diffuse infiltration to develop effective therapies. Methods: We integrated in vitro and in vivo functional assays, RNA sequencing, clinical, and expression information from public data sets to investigate the role of ADAM23 expression coupling astrocytoma's growth and motility. Results: ADAM23 downregulation resulted in increased infiltration, reduced tumor growth, and improved overall survival in astrocytomas. Additionally, we show that ADAM23 deficiency induces γ-secretase (GS) complex activity, contributing to the production and deposition of the Amyloid-ß and release of NICD. Finally, GS ablation in ADAM23-low astrocytomas induced a significant inhibitory effect on the invasive programs. Conclusions: Our findings reveal a role for ADAM23 in regulating the balance between cell proliferation and invasiveness in astrocytoma cells, proposing GS inhibition as a therapeutic option in ADAM23 low-expressing astrocytomas.

2.
Arch Rheumatol ; 38(2): 189-199, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37680507

RESUMO

Objectives: This study aims to evaluate the effects of exercise training on intramuscular lipid content and genes related to insulin pathway in patients with systemic autoimmune myopathies (SAMs). Patients and methods: Between January 2016 and May 2019, a total of seven patients with dermatomyositis (DM; 3 males, 4 females; mean age: 49.8±2.3 years; range, 43 to 54 years), six with immune mediated necrotizing myopathy (IMNM; 3 males, 3 females; mean age: 58.5±10.6 years; range, 46 to 74 years), and 10 control individuals (CTRL group; 4 males, 6 females; mean age: 48.7±3.9 years; range, 41 to 56 years) were included. The muscle biopsy before and after the intervention was performed to evaluate the intramuscular lipid content. Patients underwent a combined exercise training program for 12 weeks. Skeletal muscle gene expression was analyzed and the DM versus CTRL group, DM pre- and post-, and IMNM pre- and post-intervention were compared. Results: The DM group had a higher intramuscular lipid content in type II muscle fibers compared to the CTRL group. After the intervention, there was a reduction of lipid content in type I and II fibers in DM and IMNM group. The CTRL group showed a significantly higher expression of genes related to insulin and lipid oxidation pathways (AMPKß2, AS160, INSR, PGC1-α, PI3K, and RAB14) compared to the DM group. After exercise training, there was an increase gene expression related to insulin pathway and lipid oxidation in DM group (AMPKß2, AS160, INSR, PGC1-α, PI3K, and RAB14) and in IMNM group (AKT2, AMPKß2, RAB10, RAB14, and PGC1-α). Conclusion: Exercise training attenuated the amount of fat in type I and II muscle fibers in patients with DM and IMNM and increased gene expression related to insulin pathways and lipid oxidation in DM and IMNM. These results suggest that exercise training can improve the quality and metabolic functions of skeletal muscle in these diseases.

3.
Cancers (Basel) ; 15(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36765551

RESUMO

Glioblastoma (GBM) is an aggressive brain cancer associated with poor overall survival. The metabolic status and tumor microenvironment of GBM cells have been targeted to improve therapeutic strategies. TLR4 is an important innate immune receptor capable of recognizing pathogens and danger-associated molecules. We have previously demonstrated the presence of TLR4 in GBM tumors and the decreased viability of the GBM tumor cell line after lipopolysaccharide (LPS) (TLR4 agonist) stimulation. In the present study, metformin (MET) treatment, used in combination with temozolomide (TMZ) in two GBM cell lines (U87MG and A172) and stimulated with LPS was analyzed. MET is a drug widely used for the treatment of diabetes and has been repurposed for cancer treatment owing to its anti-proliferative and anti-inflammatory actions. The aim of the study was to investigate MET and LPS treatment in two GBM cell lines with different metabolic statuses. MET treatment led to mitochondrial respiration blunting and oxidative stress with superoxide production in both cell lines, more markedly in U87MG cells. Decreased cell viability after MET + TMZ and MET + LPS + TMZ treatment was observed in both cell lines. U87MG cells exhibited apoptosis after MET + LPS + TMZ treatment, promoting increased ER stress, unfolded protein response, and BLC2 downregulation. LPS stimulation of U87MG cells led to upregulation of SOD2 and genes related to the TLR4 signaling pathway, including IL1B and CXCL8. A172 cells attained upregulated antioxidant gene expression, particularly SOD1, TXN and PRDX1-5, while MET treatment led to cell-cycle arrest. In silico analysis of the TCGA-GBM-RNASeq dataset indicated that the glycolytic plurimetabolic (GPM)-GBM subtype had a transcriptomic profile which overlapped with U87MG cells, suggesting GBM cases exhibiting this metabolic background with an activated inflammatory TLR4 pathway may respond to MET treatment. For cases with upregulated CXCL8, coding for IL8 (a pro-angiogenic factor), combination treatment with an IL8 inhibitor may improve tumor growth control. The A172 cell line corresponded to the mitochondrial (MTC)-GBM subtype, where MET plus an antioxidant inhibitor, such as anti-SOD1, may be indicated as a combinatory therapy.

4.
J Neurosurg ; 138(3): 649-662, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36029259

RESUMO

OBJECTIVE: The authors searched for genetic and transcriptional signatures associated with tumor progression and recurrence in their cohort of patients with meningiomas, combining the analysis of targeted exome, NF2-LOH, transcriptome, and protein expressions. METHODS: The authors included 91 patients who underwent resection of intracranial meningioma at their institution between June 2000 and November 2007. The search of somatic mutations was performed by Next Generation Sequencing through a customized panel and multiplex ligation-dependent probe amplification for NF2 loss of heterozygosity. The transcriptomic profile was analyzed by QuantSeq 3' mRNA-Seq. The differentially expressed genes of interest were validated at the protein level analysis by immunohistochemistry. RESULTS: The transcriptomic analysis identified an upregulated set of genes related to metabolism and cell cycle and downregulated genes related to immune response and extracellular matrix remodeling in grade 2 (atypical) meningiomas, with a significant difference in recurrent compared with nonrecurrent cases. EZH2 nuclear positivity associated with grade 2, particularly with recurrent tumors and EZH2 gene expression level, correlated positively with the expression of genes related to cell cycle and negatively to genes related to immune response and regulation of cell motility. CONCLUSIONS: The authors identified modules of dysregulated genes in grade 2 meningiomas related to the activation of oxidative metabolism, cell division, cell motility due to extracellular remodeling, and immune evasion that were predictive of survival and exhibited significant correlations with EZH2 expression.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/cirurgia , Neoplasias Meníngeas/cirurgia , Recidiva Local de Neoplasia/patologia , Ciclo Celular , Divisão Celular , Proteína Potenciadora do Homólogo 2 de Zeste/genética
5.
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
6.
Adv Exp Med Biol ; 1382: 39-70, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36029403

RESUMO

Aberrant glycosylation has been associated with several processes of tumorigenesis from cell signaling, migration and invasion, to immune regulation and metastasis formation. The biosynthesis of glycoconjugates is regulated through concerted and finely tuned enzymatic reactions. This includes the levels and activity of glycosyltransferases and glycosidases, nucleotide sugar metabolism, substrate availability, epigenetic condition, and cellular functional state. Glioblastoma (GBM) is the most aggressive brain tumor, frequently occurring in adults with overall survival not surpassing 17 months after diagnosis. GBM has been classified by the World Health Organization (WHO) as a grade 4 astrocytoma and stratified into G-CIMP, proneural, classical, and mesenchymal subtypes. Several biomolecular features associated with GBM aggressiveness have been elucidated; however, more studies are needed to elucidate the role of glycosylation in GBM pathology, looking at their potential as cancer targets. Here, we focus on the alteration of genes involved in protein N- and O-linked glycosylation in GBM. Specifically, the mRNA levels of glycogenes were analyzed using astrocytoma-TCGA-RNAseq datasets from public repositories. A total of 68 genes were differentially regulated in the most aggressive, mesenchymal subtype of GBM compared to the proneural and classical subtypes, and the expression of these genes was compared to normal brain tissues. Among them, we focused on 38 genes coding for proteins that belong to: 1) asparagine glycosylation (ALG); 2) glycosyltransferases (B3T, B4T); 3) fucosyltransferase (FUT); 4) acetylgalactosaminyltransferases (GALNT); 5) hexosaminidase (HEX); 6) mannosidase (MAN); 7) acetylglucosaminyltransferase (MGAT); 8) sialidase or neuraminidase (NEU); 9) solute carrier 35 family (SLC); and 10) sialyltransferase (ST). The differential expression of some genes was already reported in several solid tumors; however, several of them were found to be dysregulated in GBM for the first time. These data represent an important starting point to perform further orthogonal and functional validations to pinpoint the role of these glycogenes in GBM as diagnostic and therapeutic targets.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glicosilação , Glicosiltransferases , Humanos
7.
J Mol Med (Berl) ; 99(8): 1101-1113, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33903940

RESUMO

Although ependymoma (EPN) molecular subgroups have been well established by integrated high-throughput platforms, low- and middle-income countries still need low-cost techniques to promptly classify these molecular subtypes. Here, we applied low-cost methods to classify EPNs from a Brazilian cohort with 60 pediatric EPN patients. Fusion transcripts (C11orf95-RELA, YAP1-MAMLD1, and YAP1-FAM118B) were investigated in supratentorial EPN (ST-EPNs) samples through RT-PCR/Sanger sequencing and immunohistochemistry (IHC) for p65/L1CAM. qRT-PCR and IHC were used to evaluate expression profiling of CXorf67, LAMA2, NELL2, and H3K27me3 in posterior fossa EPN (PF-EPNs) samples. In silico analysis was performed using public microarray data to validate the molecular assignment PF-EPNs with LAMA2/NELL2 markers. RELA cases and YAP1-MAMLD1 fusions were identified in nine and four ST-EPNs, respectively. An additional RELA case was identified by IHC. Of note, LAMA2 and NELL2 gene expression and immunoprofiling were less accurate for classifying PF-EPNs, which were confirmed by in silico analysis. Yet, H3K27me3 staining was sufficient to classify PF-EPN subgroups. Our results emphasize the feasibility of a simplified strategy to molecularly classify EPNs in the vast majority of cases (49/60; 81.7%). A coordinated combination of simple methods can be effective to screen pediatric EPN with the available laboratory resources at most low-/mid-income countries, giving support for clinical practice in pediatric EPN. KEY MESSAGES: Low- and middle-income countries need effective low-cost approaches to promptly distinguish between EPN molecular subgroups. RT-PCR plus Sanger sequencing is able to recognize the most common types of RELA and YAP1 fusion transcripts in ST-EPNs. Genetic and protein expressions of LAMA2 and NELL2 are of limited value to accurately stratify PF-EPNs. Immunohistochemical staining for H3K27me3 may be used as a robust method to accurately diagnose PF-EPNs subgroups. A coordinated flow diagram based on these validated low-cost methods is proposed to help clinical-decision making and to reduce costs with NGS assessment outside research protocols.


Assuntos
Ependimoma/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Algoritmos , Biomarcadores Tumorais/genética , Brasil , Criança , Biologia Computacional/métodos , Gerenciamento Clínico , Suscetibilidade a Doenças , Ependimoma/etiologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Técnicas de Diagnóstico Molecular/economia , Técnicas de Diagnóstico Molecular/normas , Gradação de Tumores , Estadiamento de Neoplasias , Proteínas de Fusão Oncogênica/genética , Curva ROC , Reprodutibilidade dos Testes , Análise de Sequência de DNA
8.
Cancer Metab ; 9(1): 18, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33910646

RESUMO

BACKGROUND: Glioblastoma is the most frequent and high-grade adult malignant central nervous system tumor. The prognosis is still poor despite the use of combined therapy involving maximal surgical resection, radiotherapy, and chemotherapy. Metabolic reprogramming currently is recognized as one of the hallmarks of cancer. Glutamine metabolism through glutaminolysis has been associated with tumor cell maintenance and survival, and with antioxidative stress through glutathione (GSH) synthesis. METHODS: In the present study, we analyzed the glutaminolysis-related gene expression levels in our cohort of 153 astrocytomas of different malignant grades and 22 non-neoplastic brain samples through qRT-PCR. Additionally, we investigated the protein expression profile of the key regulator of glutaminolysis (GLS), glutamate dehydrogenase (GLUD1), and glutamate pyruvate transaminase (GPT2) in these samples. We also investigated the glutathione synthase (GS) protein profile and the GSH levels in different grades of astrocytomas. The differential gene expressions were validated in silico on the TCGA database. RESULTS: We found an increase of glutaminase isoform 2 gene (GLSiso2) expression in all grades of astrocytoma compared to non-neoplastic brain tissue, with a gradual expression increment in parallel to malignancy. Genes coding for GLUD1 and GPT2 expression levels varied according to the grade of malignancy, being downregulated in glioblastoma, and upregulated in lower grades of astrocytoma (AGII-AGIII). Significant low GLUD1 and GPT2 protein levels were observed in the mesenchymal subtype of GBM. CONCLUSIONS: In glioblastoma, particularly in the mesenchymal subtype, the downregulation of both genes and proteins (GLUD1 and GPT2) increases the source of glutamate for GSH synthesis and enhances tumor cell fitness due to increased antioxidative capacity. In contrast, in lower-grade astrocytoma, mainly in those harboring the IDH1 mutation, the gene expression profile indicates that tumor cells might be sensitized to oxidative stress due to reduced GSH synthesis. The measurement of GLUD1 and GPT2 metabolic substrates, ammonia, and alanine, by noninvasive MR spectroscopy, may potentially allow the identification of IDH1mut AGII and AGIII progression towards secondary GBM.

9.
Clin Neurol Neurosurg ; 190: 105647, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31945623

RESUMO

OBJECTIVE: The aim of the present study was to analyze if the pathway Skp2-p27-cyclin E1 could also be a tumor progression marker for meningiomas. PATIENTS AND METHODS: We used quantitative real-time PCR to assess the relative expression levels of the genes coding for cyclin E1 (CCNE1), Skp2 (SKP2), and p27 (P27). The expression levels were compared in grades I to III meningiomas and among different histological subtypes of grade I meningiomas. RESULTS: Anaplastic meningiomas accounted for 4.9%, atypical meningiomas for 23.5% and grade I meningiomas for 71.6%.CCNE1 expression level was significantly higher in grade II compared to grade I meningiomas (p = 0.0027), and its expression level reliably predicts grade II meningiomas (ROC AUC = 0.731, p = 0.003). CCNE1 expression also correlated with SKP2 and P27 expression levels in grade I meningiomas (r = 0.539, p < 0.0001 and r = 0.687, p = <0.0001, respectively for CCNE1/SKP2 and CCNE1/P27, Spearman's test). Fibrous subtype among grade I meningiomas presented the highest expression levels of CCNE1, SKP2 and P27. Higher expression of cyclin E1 protein was detected in the nuclei of atypical meningiomas compared to grade I meningiomas. CONCLUSIONS: CCNE1 expression level predicts meningioma malignancy, and the fibrous subtype presents the highest gene expression levels among grade I meningiomas.


Assuntos
Ciclina E/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Proteínas Oncogênicas/genética , Proteínas Quinases Associadas a Fase S/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Neoplasias Meníngeas/classificação , Neoplasias Meníngeas/patologia , Meningioma/classificação , Meningioma/patologia , Pessoa de Meia-Idade , Gradação de Tumores , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Adulto Jovem
10.
Neurol Sci ; 41(3): 691-694, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31728854

RESUMO

BACKGROUND: Ependymoma (EPN) is the third most common childhood cancer of the central nervous system. RELA fusion-positive EPN accounts for approximately 70% of all childhood supratentorial tumors and shows the worst prognosis among the supratentorial EPNs. TP53 mutation is infrequent in RELA fusions EPNs. In the population from the Southern region of Brazil, there is a high incidence of the germline TP53 p.R337H mutation that predisposes carriers to develop early-onset tumors. However, despite this high incidence, the frequency of this mutation among EPN patients remains to be determined. Here, we investigated the presence of the TP53 p.R337H mutation in a larger cohort of pediatric EPNs of three institutions located in the state of São Paulo, Brazil. METHODS: The TP53 p.R337H mutation was screened by conventional RT-PCR and Sanger sequencing in 49 pediatric EPNs diagnosed during the period from 1995 to 2016. RESULTS: We described for the first time a case of a 5-year-old girl with RELA fusion EPN with a heterozygous TP53 p.R337H mutation. CONCLUSIONS: The present finding indicates that the TP53 p.R337H germline mutation is uncommon in patients with EPN in Brazil and screening of pediatric patients RELA fusion EPN may be informative to better understand the role of TP53 germline mutations in the development and prognosis of these tumors.


Assuntos
Ependimoma/genética , Neoplasias Supratentoriais/genética , Proteína Supressora de Tumor p53/genética , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Ependimoma/epidemiologia , Feminino , Mutação em Linhagem Germinativa , Humanos , Masculino , Neoplasias Supratentoriais/epidemiologia , Fator de Transcrição RelA
11.
Clinics ; 75: e1913, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1133412

RESUMO

OBJECTIVES: High-throughput sequencing of genomes, exomes, and disease-focused gene panels is becoming increasingly common for molecular diagnostics. However, identifying a single clinically relevant pathogenic variant among thousands of genetic polymorphisms is a challenging task. Publicly available genomic databases are useful resources to filter out common genetic variants present in the population and enable the identification of each disease-causing variant. Based on our experience applying these technologies at Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), São Paulo, Brazil, we recognized that the Brazilian population is not adequately represented in widely available genomic databases. METHODS: Here, we took advantage of our 5-year experience as a high-throughput sequencing core facility focused on individuals with putative genetic disorders to build a genomic database that may serve as a more accurate reference for our patient population: SELAdb. RESULTS/CONCLUSIONS: Currently, our database comprises a final cohort of 523 unrelated individuals, including patients or family members managed by different clinics of HCFMUSP. We compared SELAdb with other publicly available genomic databases and demonstrated that this population is very heterogeneous, largely resembling Latin American individuals of mixed origin, rather than individuals of pure European ancestry. Interestingly, exclusively through SELAdb, we identified a spectrum of known and potentially novel pathogenic variants in genes associated with highly penetrant Mendelian disorders, illustrating that pathogenic variants circulating in the Brazilian population that is treated in our clinics are underrepresented in other population databases. SELAdb is freely available for public consultation at: http://intranet.fm.usp.br/sela


Assuntos
Humanos , Genômica , Bases de Dados Genéticas , Brasil , Estudos de Coortes , Sequenciamento de Nucleotídeos em Larga Escala
12.
Acta Neuropathol Commun ; 7(1): 33, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832734

RESUMO

Next-generation sequencing platforms are routinely used for molecular assignment due to their high impact for risk stratification and prognosis in medulloblastomas. Yet, low and middle-income countries still lack an accurate cost-effective platform to perform this allocation. TaqMan Low Density array (TLDA) assay was performed using a set of 20 genes in 92 medulloblastoma samples. The same methodology was assessed in silico using microarray data for 763 medulloblastoma samples from the GSE85217 study, which performed MB classification by a robust integrative method (Transcriptional, Methylation and cytogenetic profile). Furthermore, we validated in 11 MBs samples our proposed method by Methylation Array 450 K to assess methylation profile along with 390 MB samples (GSE109381) and copy number variations. TLDA with only 20 genes accurately assigned MB samples into WNT, SHH, Group 3 and Group 4 using Pearson distance with the average-linkage algorithm and showed concordance with molecular assignment provided by Methylation Array 450 k. Similarly, we tested this simplified set of gene signatures in 763 MB samples and we were able to recapitulate molecular assignment with an accuracy of 99.1% (SHH), 94.29% (WNT), 92.36% (Group 3) and 95.40% (Group 4), against 97.31, 97.14, 88.89 and 97.24% (respectively) with the Ward.D2 algorithm. t-SNE analysis revealed a high level of concordance (k = 4) with minor overlapping features between Group 3 and Group 4. Finally, we condensed the number of genes to 6 without significantly losing accuracy in classifying samples into SHH, WNT and non-SHH/non-WNT subgroups. Additionally, we found a relatively high frequency of WNT subgroup in our cohort, which requires further epidemiological studies. TLDA is a rapid, simple and cost-effective assay for classifying MB in low/middle income countries. A simplified method using six genes and restricting the final stratification into SHH, WNT and non-SHH/non-WNT appears to be a very interesting approach for rapid clinical decision-making.


Assuntos
Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Meduloblastoma/genética , Meduloblastoma/patologia , Análise Serial de Proteínas/métodos , Adolescente , Criança , Pré-Escolar , Metilação de DNA/fisiologia , Feminino , Seguimentos , Humanos , Lactente , Masculino , Adulto Jovem
13.
Int J Mol Sci ; 20(5)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845661

RESUMO

Glioblastoma (GBM) is the most aggressive type of brain tumor, with an overall survival of 17 months under the current standard of care therapy. CD99, an over-expressed transmembrane protein in several malignancies, has been considered a potential target for immunotherapy. To further understand this potentiality, we analyzed the differential expression of its two isoforms in human astrocytoma specimens, and the CD99 involved signaling pathways in glioma model U87MG cell line. CD99 was also analyzed in GBM molecular subtypes. Whole transcriptomes by RNA-Seq of CD99-siRNA, and functional in vitro assays in CD99-shRNA, that are found in U87MG cells, were performed. Astrocytoma of different malignant grades and U87MG cells only expressed CD99 isoform 1, which was higher in mesenchymal and classical than in proneural GBM subtypes. Genes related to actin dynamics, predominantly to focal adhesion, and lamellipodia/filopodia formation were down-regulated in the transcriptome analysis, when CD99 was silenced. A decrease in tumor cell migration/invasion, and dysfunction of focal adhesion, were observed in functional assays. In addition, a striking morphological change was detected in CD99-silenced U87MG cells, further corroborating CD99 involvement in actin cytoskeleton rearrangement. Inhibiting the overexpressed CD99 may improve resectability and decrease the recurrence rate of GBM by decreasing tumor cells migration and invasion.


Assuntos
Antígeno 12E7/genética , Antígeno 12E7/metabolismo , Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica/métodos , Glioblastoma/genética , Regulação para Cima , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Quinase 1 de Adesão Focal/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes src/genética , Glioblastoma/metabolismo , Humanos , Invasividade Neoplásica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Interferente Pequeno/farmacologia , Análise de Sequência de RNA
14.
Childs Nerv Syst ; 35(4): 689-694, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30631904

RESUMO

BACKGROUND: Ependymoma (EPN) is the third most common central nervous system tumor in childhood. Recent advances in the molecular classification of EPN revealed a supratentorial (ST) ependymoma subgroup characterized by C11orf95-RELA fusion. CASE REPORT: We describe a novel RELA-fusion composed by a chimeric transcript C11orf95-LOC-RELA in a supratentorial WHO grade II EPN occurring in a 4-year-old child. Metastatic loci at the brain, leptomeningeal involvement, and pulmonary nodules were identified at tumor recurrence. The child eventually died before 1 year after recurrence. CONCLUSION: This index case showed aggressive behavior and nuclear accumulation of p65/RELA.


Assuntos
Ependimoma/genética , Proteínas de Fusão Oncogênica/genética , Proteínas/genética , Neoplasias Supratentoriais/genética , Fator de Transcrição RelA/genética , Pré-Escolar , Ependimoma/patologia , Humanos , Masculino , Neoplasias Supratentoriais/patologia
15.
Clin Neurol Neurosurg ; 176: 89-96, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30553171

RESUMO

Meningiomas, tumors that originate from meningothelial cells, account for approximately 30% of all new diagnoses of central nervous system neoplasms. According to the 2016 WHO classification of central nervous system tumors meningiomas are classified into three grades: I, II, and III. Past studies have shown that the risk of meningiomas recurrence is strongly correlated with the molecular profile of the tumor. Extensive whole-exome or whole-genome sequencing has provided a large body of information about the mutational landscape of meningiomas. However, such a stratification of meningiomas based on mutational analysis alone has been proven not to satisfy the clinical need for distinction between patients who need (or do not need) an adjuvant treatment. Combined analysis of exome, transcriptome, methylome and future approaches for epigenetic aspects in meningiomas may allow researchers to unveil a more comprehensive understanding of tumor progression mechanisms and, consequently, a more personalized clinical approach for patients with meningioma. A better understanding of the genetics and clinical behavior of high-grade meningiomas is mandatory in order to better design future clinical trials. By studying the mechanisms underlying these new tumorigenesis pathways, we should be able to offer personalized chemotherapy to patients with surgery and radiation-refractory meningiomas in the near future. The purpose of this article is to accurately bring the compilation of this information, for a greater understanding of the subject.


Assuntos
Neoplasias do Sistema Nervoso Central/patologia , Meningioma/genética , Meningioma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias do Sistema Nervoso Central/diagnóstico , Análise Mutacional de DNA , Humanos , Neoplasias Meníngeas/patologia , Meningioma/diagnóstico , Mutação/genética
16.
PLoS One ; 13(6): e0199211, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29912993

RESUMO

Toll-like receptors (TLRs) are the first to identify disturbances in the immune system, recognizing pathogens such as bacteria, fungi, and viruses. Since the inflammation process plays an important role in several diseases, TLRs have been considered potential therapeutic targets, including treatment for cancer. However, TLRs' role in cancer remains ambiguous. This study aims to analyze the expression levels of plasmatic cell membrane TLRs (TLR1, TLR2, TLR4, TLR5, and TLR6) in human astrocytomas the most prevalent tumors of CNS different grades (II-IV). We demonstrated that TLR expressions were higher in astrocytoma samples compared to non-neoplastic brain tissue. The gene and protein expressions were observed in GBM cell lines U87MG and A172, proving their presence in the tumor cells. Associated expressions between the known heterodimers TLR1-TLR2 were found in all astrocytoma grades. In GBMs, the mesenchymal subtype showed higher levels of TLR expressions in relation to classical and proneural subtypes. A strong association of TLRs with the activation of cell cycle process and signaling through canonical, inflammasome and ripoptosome pathways was observed by in silico analysis, further highlighting TLRs as interesting targets for cancer treatment.


Assuntos
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Membrana Celular/metabolismo , Receptores Toll-Like/metabolismo , Encéfalo/metabolismo , Linhagem Celular Tumoral , Imunofluorescência , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Receptor 1 Toll-Like/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor 5 Toll-Like/metabolismo , Receptor 6 Toll-Like/metabolismo
17.
Adv Rheumatol ; 58(1): 37, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30657098

RESUMO

BACKGROUND: Different inflammatory cells (i.e., CD4, CD8, CD20 and CD68) are involved in pathogenesis of DM muscle. In this context, the aim of this study was to assess and compare these inflammatory cell phenotyping in muscle samples of treatment naive juvenile and adult patients with dermatomyositis. METHODS: This is a cross-sectional study, in which 28 untreated juvenile and 28 adult untreated dermatomyositis patients were included. Immunohistochemical analysis was performed on serial frozen muscle sections. Inflammatory cell phenotyping was analyzed quantitatively in endomysium, perimysium, and perivascular (endomysium and perimysium) area. RESULTS: Mean age at disease onset was 7.3 and 42.0 years in juvenile and adult dermatomyositis, respectively. Both groups had comparable time duration from symptom's onset to biopsy performance. CD4 and CD8 positive cells distributions were similar in both groups in all analyzed area, except for more predominance of CD4 in perimysium at juvenile muscle biopsies. The CD20 and CD68 positive cells were predominantly observed in adult muscle biopsy sections, when compared to juvenile samples, except for similar distribution of CD20 in perivascular endomysium, and CD68 in perimysium. CONCLUSIONS: These data show that the differences between juvenile and adult dermatomyositis may be restricted not only to patients' age, but also to different inflammatory cell distribution, particularly, in new-onset disease. Further studies are necessary to confirm the present study data and to analyze meaning of the different inflammatory cell phenotyping distribution finding in these both diseases.


Assuntos
Dermatomiosite/patologia , Músculo Esquelético/patologia , Adulto , Fatores Etários , Idade de Início , Antígenos CD/análise , Antígenos CD20/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biópsia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Criança , Estudos Transversais , Dermatomiosite/imunologia , Feminino , Secções Congeladas , Humanos , Imuno-Histoquímica , Masculino , Músculo Esquelético/imunologia , Fenótipo
18.
MedicalExpress (São Paulo, Online) ; 4(5)Sept.-Oct. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-894363

RESUMO

OBJECTIVE: To analyze the associated expression of STMN1, MELK and FOXM1 in search of alternative drugable target in glioblastoma (GBM) and to review relevant functional roles of STMN1 in cancer biology. METHOD: STMN1, MELK and FOXM1 expressions were studied by quantitative PCR and their coexpressions were analyzed in two independent glioblastoma cohorts. A review of articles in indexed journals that addressed the multiple functional aspects of STMN1 was conducted, focusing on the most recent reports discussing its role in cancer, in chemoresistance and in upstream pathways involving MELK and FOXM1. RESULTS: Significant associated expressions of MELK and FOXM1 were observed with STMN1 in GBM. Additionally, the literature review highlighted the relevance of STMN1 in cancer progression. CONCLUSION: STMN1 is very important to induce events in cancer development and progression, as cellular proliferation, migration, and drug resistance. Therefore, STMN1 can be an important therapeutic target for a large number of human cancers. In glioblastoma, the most aggressive brain tumor, the MELK/FOXM1/STMN1 presented significant associated expressions, thus pointing MELK and FOXM1 as alternative targets for therapy instead of STMN1, which is highly expressed in normal brain tissue. Continuous functional research to understand the STMN1 signaling pathway is worthwhile to improve the therapeutic approaches in cancer.


OBJETIVO: Analisar as expressões associadas de STMN1, MELK e FOXM1 na procura de alvos alternativos de tratamento em glioblastoma (GBM) e revisar os papeis funcionais relevantes de STMN1 na biologia do câncer. MÉTODO: As expressões de STMN1, MELK e FOXM1 foram estudadas por PCR quantitativo e suas coexpressões foram analisadas em dois coortes independentes de GBM. A revisão dos artigos publicados em revistas indexadas na procura dos aspectos funcionais múltiplos de STMN1 foi conduzida focando-se nos estudos mais recentes discutindo o seu papel em câncer, quimiorresistência e vias de sinalização envolvendo MELK e FOXM1. RESULTADOS: Observou-se expressões associadas significantes de MELK e FOXM1 com STMN1. Adicionalmente, a revisão da literatura salientou a relevância do STMN1 na progressão do câncer. CONCLUSÃO: STMN1 é muito importante nos eventos relacionados ao desenvolvimento e progressão do câncer, como proliferação celular, migração e resistência ao tratamento. Desta forma, STMN1 pode ser um forte alvo terapêutico em um grande número de cânceres humanos. Em GBM, o tumor cerebral mais agressivo, MELK/FOXM1/STMN1 apresentaram significativa associação em suas expressões gênicas, indicando, portanto, MELK e FOXM1 como alvos alternativos para terapia em substituição ao STMN1, que apresenta alta expressão no tecido cerebral normal. Perseverar nos estudos funcionais para o entendimento da via de sinalização do STMN1 é relevante para melhorar os esquemas terapêuticos para câncer.


Assuntos
Humanos , Glioblastoma/terapia , Estatmina/análise , Proteína Forkhead Box M1/análise , Citoesqueleto , Microtúbulos
19.
MedicalExpress (São Paulo, Online) ; 4(4)July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894358

RESUMO

OBJECTIVES. The ANKRD1 gene codes for the ankyrin repeat domain containing protein 1 and has an important role in myogenesis and possibly also in angiogenesis. Microvasculopathy is a cornerstone and an early pathological marker of change in dermatomyositis, leading to hypoxia and muscle perifascicular atrophy. These alterations could upregulate genes involved in myogenesis and angiogenesis such as ANKRD1. Therefore, we analyzed ANKRD1 expression in muscle biopsies of dermatomyositis and correlated with other hypoxia parameters and with histological changes. METHODS. Total RNA was extracted from frozen muscle biopsies samples of 29 dermatomyositis patients. A control group consisted of 20 muscle biopsies from adult patients with non-inflammatory myopathy diseases. The gene coding for hypoxia-inducible factor 1, alpha subunit (HIF1A), was analyzed to estimate the degree of hypoxia. ANKRD1 and HIF1A transcript expression levels were determined by quantitative real time PCR. RESULTS. Significantly higher ANKRD1 and HIF1A expression levels were observed in dermatomyositis relative to the control group (P<0.001, both genes). In addition, ANKRD1 and HIF1A were coexpressed (r=0.703, P=0.001) and their expression levels correlated positively to perifascicular atrophy (r=0.420, P=0.023 and r=0.404, P=0.030, respectively). CONCLUSIONS. Our results demonstrate ANKRD1 overexpression in dermatomyositis correlated to HIF1A expression and perifascicular atrophy. ANKRD1 involvement in myogenesis and angiogenesis mechanisms indicates that further investigation is worthwhile.


OBJETIVOS: ANKRD1 codifica "ankyrin repeat domain containing protein 1" e tem um papel importante na miogênese e possivelmente também na angiogênese. Microvasculopatia é considerada como um ponto central e uma alteração patológica precoce na dermatomiosite (DM), levando à hipóxia e à atrofia perifascicular muscular. Estas alterações poderiam estimular genes envolvidos na miogênese e angiogênese como ANKRD1. Portanto, analisamos a expressão de ANKRD1 em biópsias musculares de DM e correlacionamos com outros parâmetros de hipóxia e alterações histológicas. MÉTODOS: O RNA total foi extraído de biópsias de músculos congelados de 29 pacientes com DM. Como grupo controle, foram usadas 20 biópsias de músculo de pacientes adultos com miopatia não-inflamatória. O gene que codifica a subunidade alfa do fator 1 induzido por hipóxia (HIF1A) foi analisado para estimar o grau de hipóxia. Os níveis de expressão dos transcritos ANKRD1 e HIF1A foram determinados por PCR quantitativa em tempo real. RESULTADOS: Níveis aumentados de expressões de ANKRD1 e HIF1A foram observados em DM quando comparados ao grupo controle (P<0,001, ambos os genes). Além disso, ANKRD1 e HIF1A apresentaram coexpressão (r=0,703, P=0,001) e seus níveis de expressão correlacionaram-se também positivamente com atrofia perifascicular (r=0,420, P=0,023 e r=0,404, P=0,030, respectivamente). CONCLUSÕES: Nossos resultados demonstraram aumento de expressão de ANKRD1 na DM, que correlacionou com a expressão de HIF1A e atrofia perifascicular. Investigações adicionais do envolvimento de ANKRD1 no mecanismo de miogênese e angiogênese devem ser realizadas.


Assuntos
Humanos , RNA/análise , Desenvolvimento Muscular , Dermatomiosite/fisiopatologia , Hipóxia
20.
J Neurooncol ; 132(3): 383-391, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28283801

RESUMO

Serum amyloid A1 (SAA1) is a sensitive acute phase reactant primarily produced by the liver in response to acute inflammation. We have recently shown that SAA affects proliferation, migration, and invasion of glioblastoma cell lines, which suggest its participation in the malignant process. Consistently, levels of SAA have been used as a non-invasive biomarker for the prognosis of many cancers. In this study, we aimed to investigate SAA serum levels and expression of SAA genes in human astrocytomas tissues. Serum and tissue samples were obtained from patients with astrocytoma grades I to III and glioblastoma (GBM or grade IV). Levels of circulating SAA were significantly higher in the serum of patients with AGII-IV when compared to non-neoplastic samples derived from non-neoplastic patients (NN) (p > 0.0001). Quantitative real time PCR (qRT-PCR) of 148 astrocytomas samples (grades I-IV) showed that SAA1 mRNA was significantly higher in GBM when compared to AGI-III and NN samples (p < 0.0001). Immunohistochemistry analysis revealed cytoplasmic positivity for SAA in GBM. There was no correlation of SAA1 with clinical end-point of overall survival among GBM patients. However, it was found a positive correlation between SAA1 and genes involved in tumor progression, such as: HIF1A (r = 0.50; p < 0.00001), CD163 (r = 0.52; p < 0.00001), CXCR4 (r = 0.42; p < 0.00001) and CXCR7 (r = 0.33; p = 0.002). In conclusions, we show that astrocytoma patients have increased levels of serum SAA and SAA1 is expressed and secreted in GBM, and its co-expression with tumor-related genes supports its involvement in GBM angiogenesis and progression.


Assuntos
Astrocitoma/patologia , Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Proteína Amiloide A Sérica/análise , Adulto , Idoso , Astrocitoma/sangue , Astrocitoma/mortalidade , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/mortalidade , Intervalo Livre de Doença , Feminino , Glioblastoma/sangue , Glioblastoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Proteína Amiloide A Sérica/metabolismo , Regulação para Cima , Adulto Jovem
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