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Glioblastoma (GBM) is the most aggressive brain tumor, still considered incurable. In this study, conducted on primary GBM stem cells (GSCs), specifically selected as the most therapy-resistant, we examined the efficacy of luteolin, a natural flavonoid, as an anti-tumoral compound. Luteolin is known to impact the sphingolipid rheostat, a pathway regulated by the proliferative sphingosine-1-phosphate (S1P) and the proapoptotic ceramide (Cer), and implicated in numerous oncopromoter biological processes. Here, we report that luteolin is able to inhibit the expression of SphK1/2, the two kinases implicated in S1P formation, and to increase the expression of both SGPL1, the lyase responsible for S1P degradation, and CERS1, the ceramide synthase 1, thus shifting the balance toward the production of ceramide. In addition, luteolin proved to decrease the expression of protumoral signaling as MAPK, RAS/MEK/ERK and PI3K/AKT/mTOR and cyclins involved in cell cycle progression. In parallel, luteolin succeeded in upregulation of proapoptotic mediators as caspases and Bcl-2 family and cell cycle controllers as p53 and p27. Furthermore, luteolin determined the shutdown of autophagy contributing to cell survival. Overall, our data support the use of luteolin as add-on therapy, having demonstrated a good ability in impairing GSC viability and survival and increasing cell sensitivity to TMZ.
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Glioblastoma , Lisofosfolipídeos , Esfingolipídeos , Esfingosina/análogos & derivados , Humanos , Glioblastoma/tratamento farmacológico , Luteolina/farmacologia , Fosfatidilinositol 3-Quinases , CeramidasRESUMO
The neurotransmitter glutamate increases cerebral blood flow by activating postsynaptic neurons and presynaptic glial cells within the neurovascular unit. Glutamate does so by causing an increase in intracellular Ca2+ concentration ([Ca2+ ]i ) in the target cells, which activates the Ca2+ /Calmodulin-dependent nitric oxide (NO) synthase to release NO. It is unclear whether brain endothelial cells also sense glutamate through an elevation in [Ca2+ ]i and NO production. The current study assessed whether and how glutamate drives Ca2+ -dependent NO release in bEND5 cells, an established model of brain endothelial cells. We found that glutamate induced a dose-dependent oscillatory increase in [Ca2+ ]i , which was maximally activated at 200 µM and inhibited by α-methyl-4-carboxyphenylglycine, a selective blocker of Group 1 metabotropic glutamate receptors. Glutamate-induced intracellular Ca2+ oscillations were triggered by rhythmic endogenous Ca2+ mobilization and maintained over time by extracellular Ca2+ entry. Pharmacological manipulation revealed that glutamate-induced endogenous Ca2+ release was mediated by InsP3 -sensitive receptors and nicotinic acid adenine dinucleotide phosphate (NAADP) gated two-pore channel 1. Constitutive store-operated Ca2+ entry mediated Ca2+ entry during ongoing Ca2+ oscillations. Finally, glutamate evoked a robust, although delayed increase in NO levels, which was blocked by pharmacologically inhibition of the accompanying intracellular Ca2+ signals. Of note, glutamate induced Ca2+ -dependent NO release also in hCMEC/D3 cells, an established model of human brain microvascular endothelial cells. This investigation demonstrates for the first time that metabotropic glutamate-induced intracellular Ca2+ oscillations and NO release have the potential to impact on neurovascular coupling in the brain.
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Encéfalo/irrigação sanguínea , Sinalização do Cálcio/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Inositol 1,4,5-Trifosfato/metabolismo , NADP/análogos & derivados , Acoplamento Neurovascular/efeitos dos fármacos , Óxido Nítrico/metabolismo , Animais , Canais de Cálcio/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Humanos , Camundongos , NADP/metabolismo , Receptores de Glutamato Metabotrópico/agonistas , Fatores de TempoRESUMO
X-linked intellectual disability (XLID) refers to a clinically and genetically heterogeneous neurodevelopmental disorder, in which males are more heavily affected than females. Among the syndromic forms of XLID, identified by additional clinical signs as part of the disease spectrum, the association between XLID and severe myopia has been poorly characterized. We used whole exome sequencing (WES) to study two Italian male twins presenting impaired intellectual function and adaptive behavior, in association with severe myopia and mild facial dysmorphisms. WES analysis detected the novel, maternally inherited, mutation c.916G > C (G306R) in the X-linked heparan sulfate 6-O-sulfotransferase 2 (HS6ST2) gene. HS6ST2 transfers sulfate from adenosine 3'-phosphate, 5'-phosphosulfate to the sixth position of the N-sulphoglucosamine residue in heparan sulfate (HS) proteoglycans. Low HS sulfation levels are associated with defective optic disc and stalk morphogenesis during mammalian visual system development. The c.916G>C variant affects the HS6ST2 substrate binding site, and its effect was considered "deleterious" by in-silico tools. An in-vitro enzymatic assay showed that the HS6ST2 mutant isoform had significantly reduced sulphotransferase activity. Taken together, the results suggest that mutant HS6ST2 is possibly involved in the development of myopia and cognitive impairment, characteristics of the probands reported here.
Assuntos
Genes Ligados ao Cromossomo X , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Mutação , Miopia/diagnóstico por imagem , Miopia/genética , Sulfotransferases/genética , Biologia Computacional/métodos , Análise Mutacional de DNA , Ativação Enzimática , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Modelos Moleculares , Linhagem , Fenótipo , Índice de Gravidade de Doença , Relação Estrutura-Atividade , Sulfotransferases/química , Sulfotransferases/metabolismo , Gêmeos Monozigóticos , Sequenciamento do ExomaRESUMO
Glioblastoma multiforme (GBM) is the most common and fatal intracranial cancer in humans and exhibits intense and aberrant angiogenesis that sustains its malignancy and involves several angiogenic signals. Among them, vascular endothelial growth factor (VEGF) plays a key role and is overexpressed in GBM. Different cells appear to act as triggers of the aberrant angiogenesis, and, among them, platelets act as key participants. In order to provide further insights into the platelet features and angiogenic role in GBM, this study investigated the effects of platelet releasate on GBM-derived endothelial cells (GECs) and the levels of VEGF and endostatin, as pro- and anti-angiogenic components of platelet releasate from GBM patients. We demonstrate for the first time that: 1) platelet releasate exerts powerful pro-angiogenic effect on GECs, suggesting it might exert a role in the aberrant angiogenesis of GBM; 2) ADP and thrombin stimulation leads to significantly higher level of VEGF, but not of endostatin, in the releasate of platelets from GBM patients than those from healthy subjects; and 3) the intraplatelet concentrations of VEGF were significantly elevated in GBM patients as compared to controls. Moreover, we found a direct correlation between platelet-released VEGF and overall survival in our patient cohort. Although preliminary, these findings prompt further investigations to clarify the biologic relevance of platelet VEGF in GBM and prospective studies for screening GBM patients for anti-VEGF therapy and/or to optimize this treatment.
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Plaquetas/metabolismo , Neoplasias Encefálicas/metabolismo , Células Endoteliais/metabolismo , Glioblastoma/metabolismo , Neovascularização Patológica/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Plaquetas/patologia , Neoplasias Encefálicas/patologia , Células Endoteliais/patologia , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Células Tumorais CultivadasRESUMO
Beyond key functions in hemostasis and thrombosis, platelets are recognized as key players of inflammation, an underlying feature of a variety of diseases. In this regard, platelets act as a circulating source of several pro- and anti-inflammatory molecules, which are secreted from their intracellular stores upon activation. Among them, mounting evidence highlights a crucial role of sphingosine-1-phosphate (S1P), a multifunctional sphingoid mediator. S1P-induced pleiotropic effects include those crucial in inflammatory processes, such as the maintenance of the endothelial barrier integrity, and leukocyte activation and recruitment at the injured site. This review outlines the peculiar features and molecular mechanisms that allow platelets for acting as a unique factory that produces and stores S1P in large quantities. A particular emphasis is placed on the autocrine and paracrine roles of S1P derived from the "inflamed" platelets, highlighting the role of its cross-talk with endothelial and blood cells involved in inflammation, and the mechanisms of its contribution to the development and progression of inflammatory diseases. Finally, potential clinical implications of platelet-derived S1P as diagnostic tool of inflammatory severity, and as therapeutic target in inflammation are discussed.
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Plaquetas/metabolismo , Inflamação/metabolismo , Lisofosfolipídeos/metabolismo , Esfingosina/análogos & derivados , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Comunicação Autócrina , Transporte Biológico , Plaquetas/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Inflamação/tratamento farmacológico , Leucócitos/metabolismo , Lisofosfolipídeos/antagonistas & inibidores , Lisofosfolipídeos/sangue , Terapia de Alvo Molecular , Ativação Plaquetária , Transdução de Sinais , Esfingosina/antagonistas & inibidores , Esfingosina/sangue , Esfingosina/metabolismo , Trombose/sangue , Trombose/metabolismoRESUMO
Complex sphingolipids are essential structural components of intestinal membranes, providing protection and integrity to the intestinal mucosa and regulating intestinal absorption processes. The role of sphingolipid signaling has been established in numerous cellular events, including intestinal cell survival, growth, differentiation, and apoptosis. A significant body of knowledge demonstrates that intestinal sphingolipids play a crucial role, as such and through their signaling pathways, in immunity and inflammatory disorders. In this review, we report on and discuss the current knowledge on the metabolism, signaling, and functional implications of sphingolipids in inflammatory bowel disease (IBD), focusing on the different aspects of sphingolipid actions on inflammatory responses and on the potential of sphingolipid-targeted molecules as anti-IBD therapeutic agents.
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Doenças Inflamatórias Intestinais/metabolismo , Esfingolipídeos/metabolismo , Animais , HumanosRESUMO
Accumulating reports suggest that human glioblastoma contains glioma stem-like cells (GSCs) which act as key determinants driving tumor growth, angiogenesis, and contributing to therapeutic resistance. The proliferative signals involved in GSC proliferation and progression remain unclear. Using GSC lines derived from human glioblastoma specimens with different proliferative index and stemness marker expression, we assessed the hypothesis that sphingosine-1-phosphate (S1P) affects the proliferative and stemness properties of GSCs. The results of metabolic studies demonstrated that GSCs rapidly consume newly synthesized ceramide, and export S1P in the extracellular environment, both processes being enhanced in the cells exhibiting high proliferative index and stemness markers. Extracellular S1P levels reached nM concentrations in response to increased extracellular sphingosine. In addition, the presence of EGF and bFGF potentiated the constitutive capacity of GSCs to rapidly secrete newly synthesized S1P, suggesting that cooperation between S1P and these growth factors is of central importance in the maintenance and proliferation of GSCs. We also report for the first time that S1P is able to act as a proliferative and pro-stemness autocrine factor for GSCs, promoting both their cell cycle progression and stemness phenotypic profile. These results suggest for the first time that the GSC population is critically modulated by microenvironmental S1P, this bioactive lipid acting as an autocrine signal to maintain a pro-stemness environment and favoring GSC proliferation, survival and stem properties.
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Neoplasias Encefálicas/patologia , Proliferação de Células/fisiologia , Glioblastoma/patologia , Lisofosfolipídeos/metabolismo , Células-Tronco Neoplásicas/fisiologia , Esfingosina/análogos & derivados , Animais , Células Cultivadas , Ceramidas/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Cloridrato de Fingolimode , Humanos , Imunossupressores/farmacologia , Antígeno Ki-67/metabolismo , Lisofosfolipídeos/farmacologia , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/efeitos dos fármacos , Propilenoglicóis/farmacologia , Esfingolipídeos/metabolismo , Esfingosina/metabolismo , Esfingosina/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Drug resistance elicited by cancer cells still constitutes a huge problem that frequently impairs the efficacy of both conventional and novel molecular therapies. Chemotherapy usually acts to induce apoptosis in cancer cells; therefore, the investigation of apoptosis control and of the mechanisms used by cancer cells to evade apoptosis could be translated in an improvement of therapies. Among many tools acquired by cancer cells to this end, the de-regulated synthesis and metabolism of sphingolipids have been well documented. Sphingolipids are known to play many structural and signalling roles in cells, as they are involved in the control of growth, survival, adhesion, and motility. In particular, in order to increase survival, cancer cells: (a) counteract the accumulation of ceramide that is endowed with pro-apoptotic potential and is induced by many drugs; (b) increase the synthesis of sphingosine-1-phosphate and glucosylceramide that are pro-survivals signals; (c) modify the synthesis and the metabolism of complex glycosphingolipids, particularly increasing the levels of modified species of gangliosides such as 9-O acetylated GD3 (αNeu5Ac(2-8)αNeu5Ac(2-3)ßGal(1-4)ßGlc(1-1)Cer) or N-glycolyl GM3 (αNeu5Ac (2-3)ßGal(1-4)ßGlc(1-1)Cer) and de-N-acetyl GM3 (NeuNH(2)ßGal(1-4)ßGlc(1-1)Cer) endowed with anti-apoptotic roles and of globoside Gb3 related to a higher expression of the multidrug resistance gene MDR1. In light of this evidence, the employment of chemical or genetic approaches specifically targeting sphingolipid dysregulations appears a promising tool for the improvement of current chemotherapy efficacy.
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Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Esfingolipídeos/metabolismo , Animais , Humanos , Modelos Biológicos , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais/efeitos dos fármacos , Esfingolipídeos/químicaRESUMO
Introduction: Glioblastoma IDH-wildtype (GBM) is the most malignant brain tumor in adults, with a poor prognosis of approximately 15 months after diagnosis. Most patients suffer from a recurrence in <1 year, and this renders GBM a life-threatening challenge. Among molecular mechanisms driving GBM aggressiveness, angiogenesis mediated by GBM endothelial cells (GECs) deserves consideration as a therapeutic turning point. In this scenario, calpains, a family of ubiquitously expressed calcium-dependent cysteine proteases, emerged as promising targets to be investigated as a novel therapeutic strategy and prognostic tissue biomarkers. Methods: To explore this hypothesis, GECs were isolated from n=10 GBM biopsies and characterized phenotypically by immunofluorescence. The expression levels of calpains were evaluated by qRT-PCR and Western blot, and their association with patients' prognosis was estimated by Pearson correlation and Kaplan-Meier survival analysis. Calpain targeting efficacy was assessed by a time- and dose-dependent proliferation curve, MTT assay for viability, caspase-3/7 activity, migration and angiogenesis in vitro, and gene and protein expression level modification. Results: Immunofluorescence confirmed the endothelial phenotype of our primary GECs. A significant overexpression was observed for calpain-1/2/3 (CAPN) and calpain-small-subunits-1/2 (CAPNS1), whereas calpastatin gene, the calpain natural inhibitor, was reported to be downregulated. A significant negative correlation was observed between CAPN1/CAPNS1 and patient overall survival. GEC challenging revealed that the inhibition of calpain-1 exerts the strongest proapoptotic efficacy, so GEC mortality reached the 80%, confirmed by the increased activity of caspase-3/7. Functional assays revealed a strong affection of in vitro migration and angiogenesis. Gene and protein expression proved a downregulation of MAPK, VEGF/VEGFRs, and Bcl-2, and an upregulation of caspases and Bax-family mediators. Conclusion: Overall, the differential expression of calpains and their correlation with patient survival suggest a novel promising target pathway, whose blockade showed encouraging results toward precision medicine strategies.
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BACKGROUND: Glioblastoma is the most aggressive primary brain malignancy in adults, with a poor prognosis of about 14 months. Recent evidence ascribed to metformin (MET), an antihyperglycemic drug, the potential to reduce cancer incidence and progression, but the molecular mechanisms underlying these effects need to be better investigated. METHODS: Here, we tested the efficacy of MET on n = 10 primary glioblastoma endothelial cells (GECs), by viability and proliferation tests, as MTT and Live/Dead assays, apoptosis tests, as annexin V assay and caspase 3/7 activity, functional tests as tube-like structure formation and migration assay and by mRNA and protein expression performed by quantitative real-time PCR analysis (qRT-PCR) and Western Blot, respectively. RESULTS: Data resulting revealed a time- and µ-dependent ability of MET to decrease cell viability and proliferation, increasing pro-apoptotic mechanisms mediated by caspases 3/7. Also, MET impacted GEC functionality with a significant decrease of angiogenesis and invasiveness potential. Mechanistically, MET was able to interfere with sphingolipid metabolism, weakening the oncopromoter signaling promoted by sphingosine-1-phosphate (S1P) and shifting the balance toward the production of the pro-apoptotic ceramide. CONCLUSIONS: These observations ascribed to MET the potential to serve as add-on therapy against glioblastoma, suggesting a repurposing of an old, totally safe and tolerable drug for novel oncology therapeutics.
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Glioblastoma is the most common primitive tumor in adult central nervous system (CNS), classified as grade IV according to WHO 2016 classification. Glioblastoma shows a poor prognosis with an average survival of approximately 15 months, representing an extreme therapeutic challenge. One of its distinctive and aggressive features is aberrant angiogenesis, which drives tumor neovascularization, representing a promising candidate for molecular target therapy. Although several pre-clinical studies and clinical trials have shown promising results, anti-angiogenic drugs have not led to a significant improvement in overall survival (OS), suggesting the necessity of identifying novel therapeutic strategies. Metformin, an anti-hyperglycemic drug of the Biguanides family, used as first line treatment in Type 2 Diabetes Mellitus (T2DM), has demonstrated in vitro and in vivo antitumoral efficacy in many different tumors, including glioblastoma. From this evidence, a process of repurposing of the drug has begun, leading to the demonstration of inhibition of various oncopromoter mechanisms and, consequently, to the identification of the molecular pathways involved. Here, we review and discuss metformin's potential antitumoral effects on glioblastoma, inspecting if it could properly act as an anti-angiogenic compound to be considered as a safely add-on therapy in the treatment and management of glioblastoma patients.
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The severity of coronavirus disease 2019 (COVID-19) is a crucial problem in patient treatment and outcome. The aim of this study is to evaluate circulating level of sphingosine-1-phosphate (S1P) along with severity markers, in COVID-19 patients. One hundred eleven COVID-19 patients and forty-seven healthy subjects were included. The severity of COVID-19 was found significantly associated with anemia, lymphocytopenia, and significant increase of neutrophil-to-lymphocyte ratio, ferritin, fibrinogen, aminotransferases, lactate dehydrogenase (LDH), C-reactive protein (CRP), and D-dimer. Serum S1P level was inversely associated with COVID-19 severity, being significantly correlated with CRP, LDH, ferritin, and D-dimer. The decrease in S1P was strongly associated with the number of erythrocytes, the major source of plasma S1P, and both apolipoprotein M and albumin, the major transporters of blood S1P. Not last, S1P was found to be a relevant predictor of admission to an intensive care unit, and patient's outcome. Circulating S1P emerged as negative biomarker of severity/mortality of COVID-19 patients. Restoring abnormal S1P levels to a normal range may have the potential to be a therapeutic target in patients with COVID-19.
Assuntos
COVID-19/sangue , Lisofosfolipídeos/sangue , Esfingosina/análogos & derivados , Idoso , Biomarcadores/sangue , COVID-19/diagnóstico , COVID-19/patologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Esfingosina/sangueRESUMO
The etiology of intervertebral disc degeneration is largely unknown, but local neuroinflammation may exert a crucial role through activation of cells as microglia and pro-inflammatory cytokines production. We aimed to compare the effect of degenerated and normal intervertebral disc microenvironment on microglial cells and the potential role of sphingosine-1-phosphate, a pro-inflammatory sphingolipid, in their crosstalk. Human degenerated intervertebral discs (Pfirrmann grade IV) were obtained at surgery for spondylolisthesis. Normal intervertebral discs were collected from cadaveric normal lumbar spines. Normal and degenerated-intervertebral discs were kept in culture to obtain media conditioning. Then, microglial cells were cocultured with conditioned media and viability, proliferation, migration, chemotaxis, and inflammatory gene expression were evaluated. The results demonstrate that conditioned media from degenerated intervertebral discs activate microglial cells, increasing chemotaxis, migration, and pro-inflammatory mediators release to a great extent than normal discs. In addition, we show that the administration of sphingosine-1-phosphate to normal intervertebral disc/microglia coculture mimicked degenerative effects. Interestingly, sphingosine-1-phosphate content in conditioned media from degenerated discs was significantly higher than that from normal ones. In addition, FTY720, a functional antagonist of sphingosine-1-phosphate, potently inhibited the effect of degenerated intervertebral discs on microglial inflammatory factor transcription and migration. Our data report, for the first time, that sphingosine-1-phosphate is involved as signal in the microenvironment of human degenerated intervertebral discs. Sphingosine-1-phosphate signaling modulation by FTY720 may induce beneficial effects in counteracting microglial activation during intervertebral disc degeneration.
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Degeneração do Disco Intervertebral/metabolismo , Lisofosfolipídeos/metabolismo , Microglia/metabolismo , Esfingosina/análogos & derivados , Animais , Linhagem Celular , Microambiente Celular , Quimiotaxia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Receptor Cross-Talk , Esfingosina/metabolismoRESUMO
Sphingolipids are a family of ubiquitous membrane components that exhibit multiple functional properties fundamental to cell properties. Sphingolipid transport represents a crucial aspect in the metabolism, signaling and biological role of sphingolipids. Different mechanisms of sphingolipid movements contribute to their selective localization in different membranes but also in different portions and sides of the same membrane, thus ensuring and regulating their interaction with different enzymes and target molecules. In this chapter we will describe the knowledge of the different mechanisms ofsphingolipid movements within and between membranes, focusing on the recent advances in this field and considering the role played by selective sphingolipid molecules in the regulation of these mechanisms.
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Esfingolipídeos/metabolismo , Animais , Transporte Biológico Ativo , Ceramidas/metabolismo , Endocitose , Glicoesfingolipídeos/metabolismo , Humanos , Bicamadas Lipídicas/metabolismo , Microdomínios da Membrana/metabolismo , Modelos Biológicos , Esfingomielinas/metabolismoRESUMO
As a key hub of malignant properties, the cancer microenvironment plays a crucial role intimately connected to tumor properties. Accumulating evidence supports that the lysophospholipid sphingosine-1-phosphate acts as a key signal in the cancer extracellular milieu. In this review, we have a particular focus on glioblastoma, representative of a highly aggressive and deleterious neoplasm in humans. First, we highlight recent advances and emerging concepts for how tumor cells and different recruited normal cells contribute to the sphingosine-1-phosphate enrichment in the cancer microenvironment. Then, we describe and discuss how sphingosine-1-phosphate signaling contributes to favor cancer hallmarks including enhancement of proliferation, stemness, invasion, death resistance, angiogenesis, immune evasion and, possibly, aberrant metabolism. We also discuss the potential of how sphingosine-1-phosphate control mechanisms are coordinated across distinct cancer microenvironments. Further progress in understanding the role of S1P signaling in cancer will depend crucially on increasing knowledge of its participation in the tumor microenvironment.
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Lisofosfolipídeos/metabolismo , Neoplasias/metabolismo , Transdução de Sinais , Esfingosina/análogos & derivados , Microambiente Tumoral , Animais , Transporte Biológico , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Esfingosina/metabolismoRESUMO
Pineal tumors are rare, about 1% of all intracranial tumors. At variance with pineocytomas, usually characterized by a good prognosis, papillary tumors behave more aggressively. Owing to their rarity, little is known about their biology and clinical behavior, moreover conflicting data on prognosis have been reported. Here we present an unusual case of papillary neuroepithelial tumor of the pineal region in a 40-year-old man who was admitted in a state of unconsciousness due to the presence of intracranial hemorrhage. After 21 days from admission, he underwent third ventriculostomy for hydrocephalus and biopsy of the lesion. Since bleeding manifestations are uncommonly associated with this kind of tumors, we performed some additional non routine laboratory tests in order to identify biological indicators of disease course and abnormal angiogenesis. Coagulation screening tests were performed to rule out the presence of coagulopathy and vascular endothelial growth factor (VEGF ) levels were measured in plasma as marker of tumor angiogenic potential. Histologic evaluation confirmed the diagnosis of a papillary tumor of the pineal region with the presence of tiny vessel lumens that may account for increased angiogenesis Coagulation screening was normal and VEGF levels were extremely high if compared to healthy individuals. After 20 months of follow-up the tumor mass, radiotherapy treated, appeared dramatically reduced at MRI evaluation, and, interestingly, VEGF levels, although still higher than in healthy individuals, resulted significantly decreased as compared to those measured at time of first hospital admission suggesting a role for VEGF as indicator of tumor aggressiveness. In conclusion, measurement of angiogenesis circulating soluble markers could have an additional feedback in the diagnosis, therapy and monitoring the disease in patients with very rare CNS tumors as papillary tumors of pineal region that have non univocal clinical behavior and prognosis.
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Biomarcadores Tumorais/sangue , Hemorragias Intracranianas/etiologia , Neoplasias Neuroepiteliomatosas/patologia , Neovascularização Patológica/patologia , Pinealoma/patologia , Fator A de Crescimento do Endotélio Vascular/sangue , Adulto , Humanos , Masculino , Neoplasias Neuroepiteliomatosas/sangue , Neoplasias Neuroepiteliomatosas/complicações , Neovascularização Patológica/sangue , Pinealoma/sangue , Pinealoma/complicaçõesRESUMO
Personalized medicine (PM) aims to optimize patient management, taking into account the individual traits of each patient. The main purpose of PM is to obtain the best response, improving health care and lowering costs. Extending traditional approaches, PM introduces novel patient-specific paradigms from diagnosis to treatment, with greater precision. In neuro-oncology, the concept of PM is well established. Indeed, every neurosurgical intervention for brain tumors has always been highly personalized. In recent years, PM has been introduced in neuro-oncology also to design and prescribe specific therapies for the patient and the patient's tumor. The huge advances in basic and translational research in the fields of genetics, molecular and cellular biology, transcriptomics, proteomics, and metabolomics have led to the introduction of PM into clinical practice. The identification of a patient's individual variation map may allow to design selected therapeutic protocols that ensure successful outcomes and minimize harmful side effects. Thus, clinicians can switch from the "one-size-fits-all" approach to PM, ensuring better patient care and high safety margin. Here, we review emerging trends and the current literature about the development of PM in neuro-oncology, considering the positive impact of innovative advanced researches conducted by a neurosurgical laboratory.
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Neoplasias Encefálicas , Neurocirurgia , Neoplasias Encefálicas/cirurgia , Humanos , Laboratórios , Medicina de Precisão , ProteômicaRESUMO
: Circulating platelets (PLTs) are able to affect glioblastoma (GBM) microenvironment by supplying oncopromoter and pro-angiogenic factors. Among these mediators, sphingosine-1-phophate (S1P) has emerged as a potent bioactive lipid enhancing cell proliferation and survival. Here, we investigated the effect of "tumor education", characterizing PLTs from GBM patients in terms of activation state, protein content, and pro-angiogenic potential. PLTs from healthy donors (HD-PLTs) and GBM patients (GBM-PLTs) were collected, activated, and analyzed by flow cytometry, immunofluorescence, and Western blotting. To assess the pro-angiogenic contribution of GBM-PLTs, a functional cord formation assay was performed on GBM endothelial cells (GECs) with PLT-releasate. GBM-PLTs expressed higher positivity for P-selectin compared to HD-PLTs, both in basal conditions and after stimulation with adenosine triphosphate (ADP) and thrombin receptor activating peptide (TRAP). PLTs showed higher expression of VEGFR-1, VEGFR-2, VWF, S1P, S1PR1, SphK1, and SPNS. Interestingly, increased concentrations of VEGF and its receptors VEGFR1 and VEGFR2, VWF, and S1P were found in GBM-PLT-releasate with respect to HD-PLTs. Finally, GBM-PLT-releasate showed a pro-angiogenic effect on GECs, increasing the vascular network's complexity. Overall, our results demonstrated the contribution of PLTs to GBM angiogenesis and aggressiveness, advancing the potential of an anti-PLT therapy and the usefulness of PLT cargo as predictive and monitoring biomarkers.
Assuntos
Biomarcadores Tumorais/metabolismo , Plaquetas/metabolismo , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Neovascularização Patológica/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismo , Difosfato de Adenosina/farmacologia , Adulto , Idoso , Plaquetas/efeitos dos fármacos , Plaquetas/patologia , Neoplasias Encefálicas/patologia , Células Cultivadas , Células Endoteliais/metabolismo , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Prognóstico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Intracellular movements of ceramide are strongly limited by its hydrophobic nature, and the mechanisms involved in ceramide transport can represent a crucial aspect of sphingolipid metabolism and signaling. The recent identification of the ceramide specific carrier protein CERT has revealed a novel pathway for the delivery of ceramide to the Golgi apparatus for sphingomyelin biosynthesis. In this study we investigated the metabolic and functional role of CERT in C6 glioma cells. These cells were found to constitutively express CERT, the protein being mainly associated with the cytosolic fraction. Metabolic experiments performed with different radioactive metabolic precursors of sphingolipids demonstrated that the down regulation of CERT by RNAi technology resulted in a significant but not complete reduction of ceramide metabolism to sphingomyelin, without affecting its utilization for glycosphingolipid biosynthesis. Since nitric oxide is an inhibitor of ceramide ER-to-Golgi traffic and metabolism in C6 glioma cells, we evaluated the possibility that the CERT-mediated transport of ceramide might represent a target for nitric oxide. The data obtained demonstrate that CERT down regulation does not affect the inhibitory activity of nitric oxide on Cer metabolism, and the effects of nitric oxide and CERT silencing on ceramide utilization were additive. These results strongly suggest that a CERT-mediated and a CERT-independent, nitric oxide-sensitive Cer transport coexist in C6 glioma cells and can separately contribute to the control of sphingolipid metabolism and Cer levels in these cells.