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1.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34201962

RESUMO

Sphingosine-1-phosphate (S1P) is a crucial mediator involved in the progression of different cancers, including glioblastoma multiforme (GBM), the most frequent and deadly human brain tumor, characterized by extensive invasiveness and rapid cell growth. Most of GBMs overexpress the epidermal growth factor receptor (EGFR), and we investigated the possible link between S1P and EGFR signaling pathways, focusing on its role in GBM survival, using the U87MG human cell line overexpressing EGFR (EGFR+). We previously demonstrated that EGFR+ cells have higher levels of extracellular S1P and increased sphingosine kinase-1 (SK1) activity than empty vector expressing cells. Notably, we demonstrated that EGFR+ cells are resistant to temozolomide (TMZ), the standard chemotherapeutic drug in GBM treatment, and the inhibition of SK1 or S1P receptors made EGFR+ cells sensitive to TMZ; moreover, exogenous S1P reverted this effect, thus involving extracellular S1P as a survival signal in TMZ resistance in GBM cells. In addition, both PI3K/AKT and MAPK inhibitors markedly reduced cell survival, suggesting that the enhanced resistance to TMZ of EGFR+ cells is dependent on the increased S1P secretion, downstream of the EGFR-ERK-SK1-S1P pathway. Altogether, our study provides evidence of a functional link between S1P and EGFR signaling pathways enhancing the survival properties of GBM cells.


Assuntos
Regulação Neoplásica da Expressão Gênica , Lisofosfolipídeos/metabolismo , Esfingosina/análogos & derivados , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Receptores ErbB/genética , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Humanos , Modelos Biológicos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Esfingosina/metabolismo
2.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202589

RESUMO

BACKGROUND: Treatment resistance of glioblastoma multiforme to chemo- and radiotherapy remains a challenge yet to overcome. In particular, the O6-methylguanine-DNA-methyltransferase (MGMT) promoter unmethylated patients have only little benefit from chemotherapy treatment using temozolomide since MGMT counteracts its therapeutic efficacy. Therefore, new treatment options in radiotherapy need to be developed to inhibit MGMT and increase radiotherapy response. METHODS: Lomeguatrib, a highly specific MGMT inhibitor, was used to inactivate MGMT protein in vitro. Radiosensitivity of established human glioblastoma multiforme cell lines in combination with lomeguatrib was investigated using the clonogenic survival assay. Inhibition of MGMT was analyzed using Western Blot. Cell cycle distribution and apoptosis were investigated to determine the effects of lomeguatrib alone as well as in combination with ionizing radiation. RESULTS: Lomeguatrib significantly decreased MGMT protein and reduced radiation-induced G2/M arrest. A radiosensitizing effect of lomeguatrib was observed when administered at 1 µM and increased radioresistance at 20 µM. CONCLUSION: Low concentrations of lomeguatrib elicit radiosensitization, while high concentrations mediate a radioprotective effect.


Assuntos
Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/genética , Purinas/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/genética , Proteínas Supressoras de Tumor/genética , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Proteínas Supressoras de Tumor/metabolismo
3.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205043

RESUMO

Glioblastoma (GBM) is the most common and most deadly primary malignant brain tumor. Current therapies are not effective, the average survival of GBM patients after diagnosis being limited to few months. Therefore, the discovery of new treatments for this highly aggressive brain cancer is urgently needed. Chalcones are synthetic and naturally occurring compounds that have been widely investigated as anticancer agents. In this work, three chalcone derivatives were tested regarding their inhibitory activity and selectivity towards GBM cell lines (human and mouse) and a non-cancerous mouse brain cell line. The chalcone 1 showed the most potent and selective cytotoxic effects in the GBM cell lines, being further investigated regarding its ability to reduce critical hallmark features of GBM and to induce apoptosis and cell cycle arrest. This derivative showed to successfully reduce the invasion and proliferation capacity of tumor cells, both key targets for cancer treatment. Moreover, to overcome potential systemic side effects and its poor water solubility, this compound was encapsulated into liposomes. Therapeutic concentrations were incorporated retaining the potent in vitro growth inhibitory effect of the selected compound. In conclusion, our results demonstrated that this new formulation can be a promising starting point for the discovery of new and more effective drug treatments for GBM.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Ciclo Celular/efeitos dos fármacos , Chalconas/farmacologia , Glioblastoma/metabolismo , Animais , Antineoplásicos/química , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chalconas/química , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , Lipossomos , Camundongos , Estrutura Molecular , Invasividade Neoplásica
4.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207114

RESUMO

Haptoglobin (Hp) is a blood plasma glycoprotein that plays a critical role in tissue protection and the prevention of oxidative damage. Haptoglobin is an acute-phase protein, its concentration in plasma changes in pathology, and the test for its concentration is part of normal clinical practice. Haptoglobin is a conservative protein and is the subject of research as a potential biomarker of many diseases, including malignant neoplasms. The Human Hp gene is polymorphic and controls the synthesis of three major phenotypes-homozygous Hp1-1 and Hp2-2, and heterozygous Hp2-1, determined by a combination of allelic variants that are inherited. Numerous studies indicate that the phenotype of haptoglobin can be used to judge the individual's predisposition to various diseases. In addition, Hp undergoes various post-translational modifications (PTMs). Glioblastoma multiform (GBM) is the most malignant primary brain tumor. In our study, we have analyzed the state of Hp proteoforms in plasma and cells using 1D (SDS-PAGE) and 2D electrophoresis (2DE) with the following mass spectrometry (LC ES-MS/MS) or Western blotting. We found that the levels of α2- and ß-chain proteoforms are up-regulated in the plasma of GBM patients. An unprocessed form of Hp2-2 (PreHp2-2, zonulin) with unusual biophysical parameters (pI/Mw) was also detected in the plasma of GBM patients and glioblastoma cells. Altogether, this data shows the possibility to use proteoforms of haptoglobin as a potential GBM-specific plasma biomarker.


Assuntos
Biomarcadores Tumorais , Glioblastoma/etiologia , Glioblastoma/metabolismo , Haptoglobinas/metabolismo , Linhagem Celular Tumoral , Cromatografia Líquida , Biologia Computacional/métodos , Suscetibilidade a Doenças , Regulação Neoplásica da Expressão Gênica , Glioblastoma/diagnóstico , Humanos , Prognóstico , Proteólise , Proteômica/métodos , Espectrometria de Massas em Tandem
5.
Mol Cell ; 81(13): 2686-2687, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34214442

RESUMO

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 , Oxirredução
6.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204510

RESUMO

Glioblastoma, a subset of aggressive brain tumors, deploy several means to increase blood vessel supply dedicated to the tumor mass. This includes typical program borrowed from embryonic development, such as vasculogenesis and sprouting angiogenesis, as well as unconventional processes, including co-option, vascular mimicry, and transdifferentiation, in which tumor cells are pro-actively engaged. However, these neo-generated vascular networks are morphologically and functionally abnormal, suggesting that the vascularization processes are rather inefficient in the tumor ecosystem. In this review, we reiterate the specificities of each neovascularization modality in glioblastoma, and, how they can be hampered mechanistically in the perspective of anti-cancer therapies.


Assuntos
Glioblastoma/metabolismo , Glioblastoma/patologia , Neovascularização Patológica/metabolismo , Animais , Biomarcadores , Comunicação Celular , Diferenciação Celular , Suscetibilidade a Doenças , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Glioblastoma/etiologia , Glioblastoma/terapia , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Tolerância a Radiação , Transdução de Sinais , Microambiente Tumoral
7.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34210107

RESUMO

Brain tumors are the most common malignant primary intracranial tumors of the central nervous system. They are often recognized too late for successful therapy. Minimally invasive methods are needed to establish a diagnosis or monitor the response to treatment of CNS tumors. Brain tumors release molecular information into the circulation. Liquid biopsies collect and analyze tumor components in body fluids, and there is an increasing interest in the investigation of liquid biopsies as a substitute for tumor tissue. Tumor-derived biomarkers include nucleic acids, proteins, and tumor-derived extracellular vesicles that accumulate in blood or cerebrospinal fluid. In recent years, circulating tumor cells have also been identified in the blood of glioblastoma patients. In this review of the literature, the authors highlight the significance, regulation, and prevalence of molecular biomarkers such as O6-methylguanine-DNA methyltransferase, epidermal growth factor receptor, and isocitrate dehydrogenase. Herein, we critically review the available literature on plasma circulating tumor cells (CTCs), cell-free tumors (ctDNAs), circulating cell-free microRNAs (cfmiRNAs), and circulating extracellular vesicles (EVs) for the diagnosis and monitoring of brain tumor. Currently available markers have significant limitations. While much research has been conductedon these markers, there is still a significant amount that we do not yet understand, which may account for some conflicting reports in the literature.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Células Neoplásicas Circulantes/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Detecção Precoce de Câncer , Vesículas Extracelulares/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Biópsia Líquida , Células Neoplásicas Circulantes/metabolismo , O(6)-Metilguanina-DNA Metiltransferase/genética , Prognóstico
8.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068110

RESUMO

The aim of the study was to investigate the anticancer potential of LY294002 (PI3K inhibitor) and temozolomide using glioblastoma multiforme (T98G) and anaplastic astrocytoma (MOGGCCM) cells. Apoptosis, autophagy, necrosis, and granules in the cytoplasm were identified microscopically (fluorescence and electron microscopes). The mitochondrial membrane potential was studied by flow cytometry. The activity of caspases 3, 8, and 9 and Akt was evaluated fluorometrically, while the expression of Beclin 1, PI3K, Akt, mTOR, caspase 12, and Hsp27 was determined by immunoblotting. SiRNA was used to block Hsp27 and PI3K expression. Cell migration and localization of Hsp27 were tested with the wound healing assay and immunocytochemistry, respectively. LY294002 effectively diminished the migratory potential and increased programmed death of T98G and MOGGCCM. Autophagy was dominant in MOGGCCM, while apoptosis was dominant in T98G. LY294002 with temozolomide did not potentiate cell death but redirected autophagy toward apoptosis, which was correlated with ER stress. A similar effect was observed after blocking PI3K expression with siRNA. Transfection with Hsp27 siRNA significantly increased apoptosis related to ER stress. Our results indicate that inhibition of the PI3K/Akt/mTOR pathway sensitizes glioma cells to apoptosis upon temozolomide treatment, which was correlated with ER stress. Hsp27 increases the resistance of glioma cells to cell death upon temozolomide treatment.


Assuntos
Biomarcadores Tumorais/metabolismo , Cromonas/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/tratamento farmacológico , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Temozolomida/farmacologia , Antineoplásicos Alquilantes/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Inibidores Enzimáticos/farmacologia , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Potencial da Membrana Mitocondrial , Necrose , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Células Tumorais Cultivadas
9.
Int J Mol Sci ; 22(11)2021 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-34072607

RESUMO

Glioblastoma (GBM) is an extremely aggressive tumor originating from neural stem cells of the central nervous system, which has high histopathological and genomic diversity. Mitochondria are cellular organelles associated with the regulation of cellular metabolism, redox signaling, energy generation, regulation of cell proliferation, and apoptosis. Accumulation of mutations in mitochondrial DNA (mtDNA) leads to mitochondrial dysfunction that plays an important role in GBM pathogenesis, favoring abnormal energy and reactive oxygen species production and resistance to apoptosis and to chemotherapeutic agents. The present review summarizes the known mitochondrial DNA alterations related to GBM, their cellular and metabolic consequences, and their association with diagnosis, prognosis, and treatment.


Assuntos
DNA Mitocondrial , Variação Genética , Glioblastoma/genética , Mitocôndrias/genética , Linhagem Celular Tumoral , Metabolismo Energético , Genoma Mitocondrial , Genômica/métodos , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Lipogênese/genética , Mitocôndrias/metabolismo , Mutação
10.
Int J Mol Sci ; 22(11)2021 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-34071132

RESUMO

Demethoxycurcumin (DMC), a derivate of curcumin, has been shown to induce apoptotic cell death in human glioblastoma multiforme GBM 8401 cells via cell cycle arrest and induction of cell apoptosis. However, there is no report showing DMC suppresses glioblastoma multiforme cells in vivo. In the present study, we investigated the effects of DMC on GBM8401 cells in vivo. At first, we established a luciferase-expressing stable clone named GBM 8401/luc2. Second, mice were inoculated subcutaneously with GBM 8401/luc2 cells to generate a xenograft tumor mice model. After inoculation, tumor volume reached 100-120 mm3, and all mice were randomly divided into three groups: Group I was treated with 110 µL phosphate-buffered solution (PBS) containing 0.1% dimethyl sulfoxide, Group II with 30 mg/kg of DMC, and Group III with 60 mg/kg of DMC. Mice from each group were given the oral treatment of DMC by gavage for 21 days. The body weight and tumor volume were recorded every 3 days. DMC significantly decreased the tumor volumes, and 60 mg/kg treatment showed a higher decrease in tumor volumes than that of 30 mg/kg, However, DMC did not affect the body weights. The photons emitted from mice tumors were detected with Xenogen IVIS imaging system, DMC at both doses decreased the total photon flux and 60 mg/kg treatment of DMC has low total photon flux than that of 30 mg/kg. The tumor volumes and weights in 60 mg/kg treatment of DMC were lower than that of 30 mg/kg. Immunohistochemical analysis was used to measure protein expression of tumors and results showed that DMC treatment led to lightly staining with anti-Bcl-2 and -XIAP and 60 mg/kg treatment of DMC has lighter staining with anti-Bcl-2 and -XIAP than that of 30 mg/kg. The higher dose (60 mg/kg) of DMC has higher signals of cleaved-caspase-3 than that of the lower dose (30 mg/kg). Furthermore, the hematoxylin and eosin (H&E) staining of liver tissues showed no significant difference between DMC-treated and control-groups. Overall, these observations showed that DMC suppressed tumor properties in vivo and DMC may be used against human glioblastoma multiforme in the future.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Diarileptanoides/uso terapêutico , Glioblastoma/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Diarileptanoides/toxicidade , Genes Reporter , Glioblastoma/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Distribuição Aleatória , Carga Tumoral , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/análise , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/análise
11.
Int J Mol Sci ; 22(10)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067658

RESUMO

Epithelial membrane protein 3 (EMP3) is a tetraspan membrane protein overexpressed in isocitrate dehydrogenase-wild-type (IDH-wt) glioblastoma (GBM). Several studies reported high EMP3 levels as a poor prognostic factor in GBM patients. Experimental findings based on glioma and non-glioma models have demonstrated the role of EMP3 in the regulation of several membrane proteins known to drive IDH-wt GBM. In this review, we summarize what is currently known about EMP3 biology. We discuss the regulatory effects that EMP3 exerts on a variety of oncogenic receptors and discuss how these mechanisms may relate to IDH-wt GBM. Lastly, we enumerate the open questions towards EMP3 function in IDH-wt GBM.


Assuntos
Glioblastoma/metabolismo , Glicoproteínas de Membrana/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/genética , Glioma/genética , Glioma/metabolismo , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Glicoproteínas de Membrana/fisiologia , Prognóstico
12.
Cell Mol Life Sci ; 78(14): 5587-5604, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34100981

RESUMO

To clarify whether differential compartmentalization of Survivin impacts temozolomide (TMZ)-triggered end points, we established a well-defined glioblastoma cell model in vitro (LN229 and A172) and in vivo, distinguishing between its nuclear and cytoplasmic localization. Expression of nuclear export sequence (NES)-mutated Survivin (SurvNESmut-GFP) led to impaired colony formation upon TMZ. This was not due to enhanced cell death but rather due to increased senescence. Nuclear-trapped Survivin reduced homologous recombination (HR)-mediated double-strand break (DSB) repair, as evaluated by γH2AX foci formation and qPCR-based HR assay leading to pronounced induction of chromosome aberrations. Opposite, clones, expressing free-shuttling cytoplasmic but not nuclear-trapped Survivin, could repair TMZ-induced DSBs and evaded senescence. Mass spectrometry-based interactomics revealed, however, no direct interaction of Survivin with any of the repair factors. The improved TMZ-triggered HR activity in Surv-GFP was associated with enhanced mRNA and stabilized RAD51 protein expression, opposite to diminished RAD51 expression in SurvNESmut cells. Notably, cytoplasmic Survivin could significantly compensate for the viability under RAD51 knockdown. Differential Survivin localization also resulted in distinctive TMZ-triggered transcriptional pathways, associated with senescence and chromosome instability as shown by global transcriptome analysis. Orthotopic LN229 xenografts, expressing SurvNESmut exhibited diminished growth and increased DNA damage upon TMZ, as manifested by PCNA and γH2AX foci expression, respectively, in brain tissue sections. Consequently, those mice lived longer. Although tumors of high-grade glioma patients expressed majorly nuclear Survivin, they exhibited rarely NES mutations which did not correlate with survival. Based on our in vitro and xenograft data, Survivin nuclear trapping would facilitate glioma response to TMZ.


Assuntos
Núcleo Celular/metabolismo , Senescência Celular , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/tratamento farmacológico , Recombinação Homóloga , Survivina/metabolismo , Temozolomida/farmacologia , Animais , Antineoplásicos Alquilantes/farmacologia , Apoptose , Biomarcadores Tumorais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Núcleo Celular/genética , Proliferação de Células , Dano ao DNA , Reparo do DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Survivina/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Nat Commun ; 12(1): 3895, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162860

RESUMO

Brain tumors are typically immunosuppressive and refractory to immunotherapies for reasons that remain poorly understood. The unbiased profiling of immune cell types in the tumor microenvironment may reveal immunologic networks affecting therapy and course of disease. Here we identify and validate the presence of hematopoietic stem and progenitor cells (HSPCs) within glioblastoma tissues. Furthermore, we demonstrate a positive link of tumor-associated HSPCs with malignant and immunosuppressive phenotypes. Compared to the medullary hematopoietic compartment, tumor-associated HSPCs contain a higher fraction of immunophenotypically and transcriptomically immature, CD38- cells, such as hematopoietic stem cells and multipotent progenitors, express genes related to glioblastoma progression and display signatures of active cell cycle phases. When cultured ex vivo, tumor-associated HSPCs form myeloid colonies, suggesting potential in situ myelopoiesis. In experimental models, HSPCs promote tumor cell proliferation, expression of the immune checkpoint PD-L1 and secretion of tumor promoting cytokines such as IL-6, IL-8 and CCL2, indicating concomitant support of both malignancy and immunosuppression. In patients, the amount of tumor-associated HSPCs in tumor tissues is prognostic for patient survival and correlates with immunosuppressive phenotypes. These findings identify an important element in the complex landscape of glioblastoma that may serve as a target for brain tumor immunotherapies.


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Células Cultivadas , Progressão da Doença , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Estimativa de Kaplan-Meier , RNA-Seq/métodos , Transdução de Sinais/genética , Análise de Célula Única/métodos , Microambiente Tumoral/genética
14.
Nat Commun ; 12(1): 3720, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140524

RESUMO

Low levels of reactive oxygen species (ROS) are crucial for maintaining cancer stem cells (CSCs) and their ability to resist therapy, but the ROS regulatory mechanisms in CSCs remains to be explored. Here, we discover that prohibitin (PHB) specifically regulates mitochondrial ROS production in glioma stem-like cells (GSCs) and facilitates GSC radiotherapeutic resistance. We find that PHB is upregulated in GSCs and is associated with malignant gliomas progression and poor prognosis. PHB binds to peroxiredoxin3 (PRDX3), a mitochondrion-specific peroxidase, and stabilizes PRDX3 protein through the ubiquitin-proteasome pathway. Knockout of PHB dramatically elevates ROS levels, thereby inhibiting GSC self-renewal. Importantly, deletion or pharmacological inhibition of PHB potently slows tumor growth and sensitizes tumors to radiotherapy, thus providing significant survival benefits in GSC-derived orthotopic tumors and glioblastoma patient-derived xenografts. These results reveal a selective role of PHB in mitochondrial ROS regulation in GSCs and suggest that targeting PHB improves radiotherapeutic efficacy in glioblastoma.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/metabolismo , Adulto , Idoso , Animais , Astrocitoma/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Inativação de Genes , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/radioterapia , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Gradação de Tumores , Peroxirredoxinas/metabolismo , Prognóstico , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Análise Serial de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065350

RESUMO

Glioblastoma (GBM) cells feature mitochondrial alterations, which are documented and quantified in the present study, by using ultrastructural morphometry. Mitochondrial impairment, which roughly occurs in half of the organelles, is shown to be related to mTOR overexpression and autophagy suppression. The novelty of the present study consists of detailing an mTOR-dependent mitophagy occlusion, along with suppression of mitochondrial fission. These phenomena contribute to explain the increase in altered mitochondria reported here. Administration of the mTOR inhibitor rapamycin rescues mitochondrial alterations. In detail, rapamycin induces the expression of genes promoting mitophagy (PINK1, PARKIN, ULK1, AMBRA1) and mitochondrial fission (FIS1, DRP1). This occurs along with over-expression of VPS34, an early gene placed upstream in the autophagy pathway. The topographic stoichiometry of proteins coded by these genes within mitochondria indicates that, a remarkable polarization of proteins involved in fission and mitophagy within mitochondria including LC3 takes place. Co-localization of these proteins within mitochondria, persists for weeks following rapamycin, which produces long-lasting mitochondrial plasticity. Thus, rapamycin restores mitochondrial status in GBM cells. These findings add novel evidence about mitochondria and GBM, while fostering a novel therapeutic approach to restore healthy mitochondria through mTOR inhibition.


Assuntos
Glioblastoma/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Sirolimo/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Humanos , Mitocôndrias/metabolismo , Serina-Treonina Quinases TOR/metabolismo
16.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070493

RESUMO

5-Aminolevulinic acid (5-ALA) is a naturally occurring non-proteinogenic amino acid, which contributes to the diagnosis and therapeutic approaches of various cancers, including glioblastoma (GBM). In the present study, we aimed to investigate whether 5-ALA exerted cytotoxic effects on GBM cells. We assessed cell viability, apoptosis rate, mRNA expressions of various apoptosis-related genes, generation of reactive oxygen species (ROS), and migration ability of the human U-87 malignant GBM cell line (U87MG) treated with 5-ALA at different doses. The half-maximal inhibitory concentration of 5-ALA on U87MG cells was 500 µg/mL after 7 days; 5-ALA was not toxic for human optic cells and NIH-3T3 cells at this concentration. The application of 5-ALA led to a significant increase in apoptotic cells, enhancement of Bax and p53 expressions, reduction in Bcl-2 expression, and an increase in ROS generation. Furthermore, the application of 5-ALA increased the accumulation of U87MG cells in the SUB-G1 population, decreased the expression of cyclin D1, and reduced the migration ability of U87MG cells. Our data indicate the potential cytotoxic effects of 5-ALA on U87MG cells. Further studies are required to determine the spectrum of the antitumor activity of 5-ALA on GBM.


Assuntos
Ácido Aminolevulínico/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
17.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065977

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is the most frequent and aggressive primary brain tumor, and macrophages account for 30-40% of its composition. Most of these macrophages derive from bone marrow monocytes playing a crucial role in tumor progression. Unraveling the mechanisms of macrophages-GBM crosstalk in an appropriate model will contribute to the development of specific and more successful therapies. We investigated the interaction of U87MG human GBM cells with primary human CD14+ monocytes or the THP-1 cell line with the aim of establishing a physiologically relevant heterotypic culture model. METHODS: primary monocytes and THP-1 cells were cultured in the presence of U87MG conditioned media or co-cultured together with previously formed GBM spheroids. Monocyte differentiation was determined by flow cytometry. RESULTS: primary monocytes differentiate to M2 macrophages when incubated with U87MG conditioned media in 2-dimensional culture, as determined by the increased percentage of CD14+CD206+ and CD64+CD206+ populations in CD11b+ cells. Moreover, the mitochondrial protein p32/gC1qR is expressed in monocytes exposed to U87MG conditioned media. When primary CD14+ monocytes or THP-1 cells are added to previously formed GBM spheroids, both invade and establish within them. However, only primary monocytes differentiate and acquire a clear M2 phenotype characterized by the upregulation of CD206, CD163, and MERTK surface markers on the CD11b+CD14+ population and induce alterations in the sphericity of the cell cultures. CONCLUSION: our results present a new physiologically relevant model to study GBM/macrophage interactions in a human setting and suggest that both soluble GBM factors, as well as cell-contact dependent signals, are strong inducers of anti-inflammatory macrophages within the tumor niche.


Assuntos
Neoplasias Encefálicas/metabolismo , Técnicas de Cocultura/métodos , Glioblastoma/metabolismo , Macrófagos/citologia , Monócitos/citologia , Biomarcadores/metabolismo , Proteínas de Transporte/metabolismo , Comunicação Celular , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Proteínas Mitocondriais/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Cultura Primária de Células , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Células THP-1
18.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065991

RESUMO

Although there are many patients with brain tumors worldwide, there are numerous difficulties in overcoming brain tumors. Among brain tumors, glioblastoma, with a 5-year survival rate of 5.1%, is the most malignant. In addition to surgical operations, chemotherapy and radiotherapy are generally performed, but the patients have very limited options. Temozolomide is the most commonly prescribed drug for patients with glioblastoma. However, it is difficult to completely remove the tumor with this drug alone. Therefore, it is necessary to discuss the potential of anticancer drugs, other than temozolomide, against glioblastomas. Since the discovery of cisplatin, platinum-based drugs have become one of the leading chemotherapeutic drugs. Although many studies have reported the efficacy of platinum-based anticancer drugs against various carcinomas, studies on their effectiveness against brain tumors are insufficient. In this review, we elucidated the anticancer effects and advantages of platinum-based drugs used in brain tumors. In addition, the cases and limitations of the clinical application of platinum-based drugs are summarized. As a solution to overcome these obstacles, we emphasized the potential of a novel approach to increase the effectiveness of platinum-based drugs.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Compostos de Platina/uso terapêutico , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Compostos de Platina/farmacologia , Análise de Sobrevida , Resultado do Tratamento
19.
Int J Mol Sci ; 22(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064291

RESUMO

The Arg-Gly-Asp (RGD) peptide shows a high affinity for αvß3 integrin, which is overexpressed in new tumor blood vessels and many types of tumor cells. The radiolabeled RGD peptide has been studied for cancer imaging and radionuclide therapy. We have developed a long-term tumor-targeting peptide DOTA-EB-cRGDfK, which combines a DOTA chelator, a truncated Evans blue dye (EB), a modified linker, and cRGDfK peptide. The aim of this study was to evaluate the potential of indium-111(111In) radiolabeled DOTA-EB-cRGDfK in αvß3 integrin-expressing tumors. The human glioblastoma cell line U-87 MG was used to determine the in vitro binding affinity of the radiolabeled peptide. The in vivo distribution of radiolabeled peptides in U-87 MG xenografts was investigated by biodistribution, nanoSPECT/CT, pharmacokinetic and excretion studies. The in vitro competition assay showed that 111In-DOTA-EB-cRGDfK had a significant binding affinity to U-87 MG cancer cells (IC50 = 71.7 nM). NanoSPECT/CT imaging showed 111In-DOTA-EB-cRGDfK has higher tumor uptake than control peptides (111In-DOTA-cRGDfK and 111In-DOTA-EB), and there is still a clear signal until 72 h after injection. The biodistribution results showed significant tumor accumulation (27.1 ± 2.7% ID/g) and the tumor to non-tumor ratio was 22.85 at 24 h after injection. In addition, the pharmacokinetics results indicated that the 111In-DOTA-EB-cRGDfK peptide has a long-term half-life (T1/2λz = 77.3 h) and that the calculated absorbed dose was safe for humans. We demonstrated that radiolabeled DOTA-EB-cRGDfK may be a promising agent for glioblastoma tumor imaging and has the potential as a theranostic radiopharmaceutical.


Assuntos
Quelantes/metabolismo , Glioblastoma/metabolismo , Oligopeptídeos/metabolismo , Animais , Linhagem Celular Tumoral , Compostos Heterocíclicos com 1 Anel/metabolismo , Xenoenxertos/metabolismo , Humanos , Radioisótopos de Índio/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Imagem Molecular/métodos , Peptídeos Cíclicos/metabolismo , Compostos Radiofarmacêuticos/metabolismo , Ratos , Distribuição Tecidual
20.
Neuroreport ; 32(9): 771-775, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-33994523

RESUMO

Since coronavirus disease 2019 (COVID-19) swept all over the world, several studies have shown the susceptibility of a patient with cancer to COVID-19. In this case, the removed glioblastoma multiforme (GBM)-adjacent (GBM-A), GBM-peritumor and GBM-central (GBM-C) tissues from a convalescent patient of COVID-19, who also suffered from glioblastoma meanwhile, together with GBM-A and GBM tissues from a patient without COVID-19 history as negative controls, were used for RNA ISH, electron microscopy observing and immunohistochemical staining of ACE2 and the virus antigen (N protein). The results of RNA ISH, electron microscopy observing showed that SARS-CoV-2 directly infects some cells within human GBM tissues and SARS-CoV-2 in GBM-C tissue still exists even when it is cleared elsewhere. Immunohistochemical staining of ACE2 and N protein showed that the expressions of ACE2 are significantly higher in specimens, including GBM-C tissue from COVID-19 patient than other types of tissue. The unique phenomenon suggests that the surgical protection level should be upgraded even if the patient is in a convalescent period and the pharyngeal swab tests show negative results. Furthermore, more attention should be paid to confirm whether the shelter-like phenomenon happens in other malignancies due to the similar microenvironment and high expression of ACE2 in some malignancies.


Assuntos
Neoplasias Encefálicas/virologia , COVID-19/metabolismo , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Glioblastoma/virologia , SARS-CoV-2/metabolismo , Adulto , Enzima de Conversão de Angiotensina 2/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/ultraestrutura , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19 , Convalescença , Glioblastoma/metabolismo , Glioblastoma/cirurgia , Glioblastoma/ultraestrutura , Humanos , Hibridização In Situ , Masculino , Microscopia Eletrônica de Transmissão , Fosfoproteínas/metabolismo , RNA Viral/metabolismo , Receptores de Coronavírus/metabolismo , SARS-CoV-2/ultraestrutura , Vírion/ultraestrutura
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