RESUMO
Cryptocarya alba (Peumo; CA) and Laurelia sempervirens (Laurel; LS) are herbs native to the Chilean highlands and have historically been used for medicinal purposes by the Huilliches people. In this work, the essential oils were extracted using hydrodistillation in Clevenger apparatus and analyzed by GC-MS to determine their composition. The antioxidant capacity (AC) was evaluated in vitro. The cytotoxicity was determined using cell line cultures both non tumoral and tumoral. The toxicity was determined using the nematode Caenorhabditis elegans. The antimicrobial activity was evaluated against 52 bacteria using the agar disc diffusion method and the minimum inhibitory concentrations (MICs) were determined. The principal compounds found in C. alba essential oil (CA_EO) were α-terpineol (24.96%) and eucalyptol (21.63%) and were isazafrol (91.9%) in L. sempervirens essential oil (LS_EO). Both EOs showed antioxidant capacity in vitro. Both EO showed antibacterial activity against bacteria using. LS_EO showed more inhibitory effect on these cell lines respect to CA_EO. Both EOs showed toxicity against the nematode C.elegans at 3.12-50 mg/mL. The essential oils of CA and LS have an important bioactive potential in their antioxidant, antibacterial and cytotoxicity activity. Both essential oils could possibly be used in the field of natural medicine, natural food preservation, cosmetics, sanitation and plaguicides among others.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Cryptocarya/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/crescimento & desenvolvimento , Proliferação de Células , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Células Tumorais CultivadasRESUMO
Diabetic nephropathy (DN) is the main cause of end-stage renal disease, which remains incurable. The progression of DN is associated with progressive and irreversible renal fibrosis and also high levels of adenosine. Our aim was to evaluate the effects of ADORA3 antagonism on renal injury in streptozotocin-induced diabetic rats. An ADORA3 antagonist that was administered in diabetic rats greatly inhibited the levels of inflammatory interleukins IL-1ß and IL-18, meanwhile when adenosine deaminase was administered, there was a non-selective attenuation of the inflammatory mediators IL-1ß, IL-18, IL-6, and induction of IL-10. The ADORA3 antagonist attenuated the high glucose-induced activation of caspase 1 in HK2 cells in vitro. Additionally, ADORA3 antagonisms blocked the increase in caspase 1 and the nuclear localization of NFκB in the renal tubular epithelium of diabetic rats, both events that are involved in regulating the production and activation of IL-1ß and IL-18. The effects of the A3 receptor antagonist resulted in the attenuation of kidney injury, as evidenced by decreased levels of the pro-fibrotic marker α-SMA at histological levels and the restoration of proteinuria in diabetic rats. We conclude that ADORA3 antagonism represents a potential therapeutic target that mechanistically works through the selective blockade of the NLRP3 inflammasome.
Assuntos
Antagonistas do Receptor A3 de Adenosina/administração & dosagem , Caspase 1/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Antagonistas do Receptor A3 de Adenosina/farmacologia , Adenosina Desaminase/efeitos adversos , Animais , Linhagem Celular , Diabetes Mellitus Experimental/enzimologia , Nefropatias Diabéticas/induzido quimicamente , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Injeções Intraperitoneais , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/enzimologia , Masculino , Ratos , EstreptozocinaRESUMO
Glioblastoma (GBM) is the most common and aggressive brain tumor, which causes the highest number of deaths worldwide. It is a highly vascularized tumor, infiltrative, and its tumorigenic capacity is exacerbated. All these hallmarks are therapeutic targets in GBM treatment, including surgical removal followed by radiotherapy and chemotherapy. Current therapies have not been sufficient for the effective patient's management, so the classic therapies have had to expand and incorporate new alternative treatments, including natural compounds. This review summarizes natural products and their physiological effects in in vitro and in vivo models of GBM, specifically by modulating signaling pathways involved in angiogenesis, cell migration/invasion, cell viability, apoptosis, and chemoresistance. The most important aspects of natural products and their derivatives were described in relation to its antitumoral effects. As a final result, it can be obtained that within the compounds with more evidence that supports or suggests its clinical use are the cannabinoids, terpenes, and curcumin, because many have been shown to have a significant effect in decreasing the progress of GBM through known mechanisms, such as chemo-sensitization or decrease migration and cell invasion. Natural compounds emerge as promising therapies to attack the progress of GBM.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Animais , Apoptose , Canabinoides/farmacologia , Movimento Celular , Sobrevivência Celular , Flavonoides/farmacologia , Humanos , Neovascularização Patológica , Óleos Voláteis/farmacologia , Polifenóis/farmacologia , Transdução de Sinais , Terpenos/farmacologiaRESUMO
Poor response to current treatments for glioblastoma has been attributed to the presence of glioblastoma stem-like cells (GSCs). GSCs are able to expel antitumor drugs to the extracellular medium using the multidrug resistance-associated protein 1 (MRP1) transporter. Tacrolimus (FK506) has been identified as an MRP1 regulator in differentiated glioblastoma (GBM) cells (non-GSCs); however, the effect of FK506 on GSCs is currently unknown. The objective of the following research is to evaluate the effect of FK506 on the MRP1-related chemo-resistant phenotype of GSCs. For this, U87MG and C6 glioma cell lines were used to generate non-GSCs and GSCs. mRNA and MRP1-positive cells were evaluated by RT-qPCR and flow cytometry, respectively. A Carboxyfluorescein Diacetate (CFDA)-retention assay was performed to evaluate the MRP1 activity. Apoptosis and MTT assays were employed to evaluate the cytotoxic effects of FK506 plus Vincristine (MRP1 substrate). GSC-derived subcutaneous tumors were generated to evaluate the in vivo effect of FK506/Vincristine treatment. No differences in transcript levels and positive cells for MRP1 were observed in FK506-treated cells. Lesser cell viability, increased apoptosis, and CFDA-retention in the FK506/Vincristine-treated cells were observed. In vivo, the FK506/Vincristine treatment decreased the tumor size as well as ki67, Glial Fibrillary Acidic Protein (GFAP), and nestin expression. We conclude that FK506 confers a chemo-sensitive phenotype to MRP1-drug substrate in GSCs.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Tacrolimo/uso terapêutico , Vincristina/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Masculino , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fenótipo , Ratos Sprague-Dawley , Tacrolimo/farmacologia , Vincristina/farmacologiaRESUMO
Glioblastoma (GBM) is a neoplasm characterized by an extensive blood vessel network. Hypoxic niches of GBM can induce tumorigenic properties of a small cell subpopulation called Glioblastoma stem-like cells (GSCs) and can also increase extracellular adenosine generation which activates the A3 adenosine receptor (A3AR). Moreover, GSCs potentiates the persistent neovascularization in GBM. The aim of this study was to determine if A3AR blockade can reduce the vasculogenesis mediated by the differentiation of GSCs to Endothelial Cells (ECs) under hypoxia. We evaluated the expression of endothelial cell markers (CD31, CD34, CD144, and vWF) by fluorescence-activated cell sorting (FACS), and vascular endothelial growth factor (VEGF) secretion by ELISA using MRS1220 (A3AR antagonist) under hypoxia. We validate our results using U87MG-GSCs A3AR knockout (GSCsA3-KO). The effect of MRS1220 on blood vessel formation was evaluated in vivo using a subcutaneous GSCs-tumor model. GSCs increased extracellular adenosine production and A3AR expression under hypoxia. Hypoxia also increased the percentage of GSCs positive for endothelial cell markers and VEGF secretion, which was in turn prevented when using MRS1220 and in GSCsA3-KO. Finally, in vivo treatment with MRS1220 reduced tumor size and blood vessel formation. Blockade of A3AR decreases the differentiation of GSCs to ECs under hypoxia and in vivo blood vessel formation.
Assuntos
Diferenciação Celular , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Receptor A3 de Adenosina/metabolismo , Adenosina/farmacologia , Antagonistas do Receptor A3 de Adenosina/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Diferenciação Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Endoteliais/efeitos dos fármacos , Humanos , Masculino , Modelos Biológicos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Ratos Sprague-DawleyRESUMO
The most aggressive type of brain tumor is glioblastoma multiforme, which to date remains incurable. Thuja occidentalis is used in homeopathy for the treatment of cancer, however, its mechanism of action remains unknown. We set out to study the effects of thujone fractions of Thuja on glioblastoma using in vitro and in vivo models. We found that the α/ ß-thujone fraction decrease the cell viability and exhibit a potent anti-proliferative, pro-apoptotic and anti-angiogenic effects in vitro. In vivo assays showed that α /ß-thujone promotes the regression of neoplasia and inhibits the angiogenic markers VEGF, Ang-4 and CD31 into the tumor.
Assuntos
Antineoplásicos/farmacologia , Glioblastoma/tratamento farmacológico , Monoterpenos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Thuja , Inibidores da Angiogênese/farmacologia , Animais , Apoptose/efeitos dos fármacos , Monoterpenos Bicíclicos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/irrigação sanguínea , Glioblastoma/patologia , Glioblastoma/fisiopatologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Masculino , Transplante de Neoplasias , Ratos Sprague-DawleyRESUMO
RATIONALE: Endothelial adherens junction proteins constitute an important element in the control of microvascular permeability. Platelet-activating factor (PAF) increases permeability to macromolecules via translocation of endothelial nitric oxide synthase (eNOS) to cytosol and stimulation of eNOS-derived nitric oxide signaling cascade. The mechanisms by which nitric oxide signaling regulates permeability at adherens junctions are still incompletely understood. OBJECTIVE: We explored the hypothesis that PAF stimulates hyperpermeability via S-nitrosation (SNO) of adherens junction proteins. METHODS AND RESULTS: We measured PAF-stimulated SNO of ß-catenin and p120-catenin (p120) in 3 cell lines: ECV-eNOSGFP, EAhy926 (derived from human umbilical vein), and postcapillary venular endothelial cells (derived from bovine heart endothelium) and in the mouse cremaster muscle in vivo. SNO correlated with diminished abundance of ß-catenin and p120 at the adherens junction and with hyperpermeability. Tumor necrosis factor-α increased nitric oxide production and caused similar increase in SNO as PAF. To ascertain the importance of eNOS subcellular location in this process, we used ECV-304 cells transfected with cytosolic eNOS (GFPeNOSG2A) and plasma membrane eNOS (GFPeNOSCAAX). PAF induced SNO of ß-catenin and p120 and significantly diminished association between these proteins in cells with cytosolic eNOS but not in cells wherein eNOS is anchored to the cell membrane. Inhibitors of nitric oxide production and of SNO blocked PAF-induced SNO and hyperpermeability, whereas inhibition of the cGMP pathway had no effect. Mass spectrometry analysis of purified p120 identified cysteine 579 as the main S-nitrosated residue in the region that putatively interacts with vascular endothelial-cadherin. CONCLUSIONS: Our results demonstrate that agonist-induced SNO contributes to junctional membrane protein changes that enhance endothelial permeability.
Assuntos
Junções Aderentes/metabolismo , Permeabilidade Capilar/fisiologia , Cateninas/metabolismo , Células Endoteliais/metabolismo , Transdução de Sinais/fisiologia , beta Catenina/metabolismo , Sequência de Aminoácidos , Animais , Permeabilidade Capilar/efeitos dos fármacos , Cateninas/genética , Bovinos , Proteínas de Fluorescência Verde/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Nitrosação/fisiologia , Fator de Crescimento Derivado de Plaquetas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Vênulas/citologia , delta CateninaRESUMO
Glioblastoma multiforme (GBM) cells are characterised by their extreme chemoresistance. The activity of multiple-drug resistance (MDR) transporters that extrude antitumor drugs from cells plays the most important role in this phenomenon. To date, the mechanism controlling the expression and activity of MDR transporters is poorly understood. Activity of the enzyme ecto-5'-nucleotidase (CD73) in tumor cells, which hydrolyses AMP to adenosine, has been linked to immunosuppression and prometastatic effects in breast cancer and to the proliferation of glioma cells. In this study, we identify a high expression of CD73 in surgically resected samples of human GBM. In primary cultures of GBM, inhibition of CD73 activity or knocking down its expression by siRNA reversed the MDR phenotype and cell viability was decreased up to 60% on exposure to the antitumoral drug vincristine. This GBM chemosensitization was caused by a decrease in the expression and activity of the multiple drug associated protein 1 (Mrp1), the most important transporter conferring multiple drug resistance in these cells. Using pharmacological modulators, we have recognized the adenosine A(3) receptor subtype in mediation of the chemoresistant phenotype in these cells. In conclusion, we have determined that the activity of CD73 to trigger adenosine signaling sustains chemoresistant phenotype in GBM cells.
Assuntos
5'-Nucleotidase/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , 5'-Nucleotidase/antagonistas & inibidores , 5'-Nucleotidase/genética , Sequência de Bases , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , RNA Interferente Pequeno/genética , Receptor A3 de Adenosina/metabolismo , Transdução de Sinais , Vincristina/farmacologiaRESUMO
Diabetic nephropathy ranks as the most devastating kidney disease worldwide. It characterizes in the early onset by glomerular hypertrophy, hyperfiltration and mesangial expansion. Experimental models show that overproduction of vascular endothelial growth factor (VEGF) is a pathogenic condition for podocytopathy; however the mechanisms that regulate this growth factor induction are not clearly identified. We determined that the adenosine A(2B) receptor (A(2B)AR) mediates VEGF overproduction in ex vivo glomeruli exposed to high glucose concentration, requiring PKCα and Erk1/2 activation. The glomerular content of A(2B)AR was concomitantly increased with VEGF at early stages of renal disease in streptozotocin-induced diabetic rats. Further, in vivo administration of an antagonist of A(2B)AR in diabetic rats blocked the glomerular overexpression of VEGF, mesangial cells activation and proteinuria. In addition, we also determined that the accumulation of extracellular adenosine occurs in glomeruli of diabetic rats. Correspondingly, raised urinary adenosine levels were found in diabetic rats. In conclusion, we evidenced that adenosine signaling at the onset of diabetic kidney disease is a pathogenic event that promotes VEGF induction.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Receptor A2B de Adenosina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Acetamidas/farmacologia , Adenosina/metabolismo , Adenosina/urina , Animais , Glicemia/metabolismo , Pressão Sanguínea/fisiologia , Peso Corporal/fisiologia , Diabetes Mellitus Experimental/urina , Nefropatias Diabéticas/urina , Histocitoquímica , Glomérulos Renais/química , Glomérulos Renais/metabolismo , Masculino , Purinas/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologiaRESUMO
Herpes simplex virus type 1 (HSV-1) is the most common pathogenic cause of sporadic acute encephalitis and it produces latent persistent infection lifelong in infected individuals. Brain inflammation is associated with activation of glial cells, which can detect pathogen-associated molecular patterns (PAMPs) through a variety of pattern-recognition receptors (PRR), including Toll-like receptors (TLRs). In this study, we evaluated the expression and activation of TLR2, TLR3, and TLR4 in HSV-1-infected astrocyte and neuronal primary cultures. Our results showed a clear induction in TLR2 and TLR4 expression in astrocytes as early as 1 h after HSV-1 infection, whereas no significant change was observed in neurons. In addition, infected astrocytes showed increased levels of interferon regulatory factors IRF3 and IRF7, interferon ß (INFß), interleukin 6 (IL6), and serum amyloid A (SAA3) transcripts, as well as phospho-IRF3 protein. These effects seemed to be dependent on viral replication since previous treatment of the cells with acyclovir resulted in low levels of TLRs expression and activation even after 4 h post-infection. These results suggest that reactivation of HSV-1 at the central nervous system (CNS) would likely induce and activate TLR2 and TLR4 receptors directly through interaction of astrocytes with the pathogen and also indirectly by endogenous ligands produced locally, such as serum amyloid protein, potentiating the neuroinflammatory response.
Assuntos
Astrócitos/metabolismo , Astrócitos/virologia , Herpesvirus Humano 1/imunologia , Proteína Amiloide A Sérica/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Regulação para Cima , Animais , Células Cultivadas , Herpesvirus Humano 1/patogenicidade , Interleucina-6/metabolismo , Ligantes , Camundongos , Neurônios/metabolismo , Neurônios/virologiaRESUMO
Glioblastoma (GBM) is the most frequent and aggressive brain tumor, characterized by great resistance to treatments, as well as inter- and intra-tumoral heterogeneity. GBM exhibits infiltration, vascularization and hypoxia-associated necrosis, characteristics that shape a unique microenvironment in which diverse cell types are integrated. A subpopulation of cells denominated GBM stem-like cells (GSCs) exhibits multipotency and self-renewal capacity. GSCs are considered the conductors of tumor progression due to their high tumorigenic capacity, enhanced proliferation, invasion and therapeutic resistance compared to non-GSCs cells. GSCs have been classified into two molecular subtypes: proneural and mesenchymal, the latter showing a more aggressive phenotype. Tumor microenvironment and therapy can induce a proneural-to-mesenchymal transition, as a mechanism of adaptation and resistance to treatments. In addition, GSCs can transition between quiescent and proliferative substates, allowing them to persist in different niches and adapt to different stages of tumor progression. Three niches have been described for GSCs: hypoxic/necrotic, invasive and perivascular, enhancing metabolic changes and cellular interactions shaping GSCs phenotype through metabolic changes and cellular interactions that favor their stemness. The phenotypic flexibility of GSCs to adapt to each niche is modulated by dynamic epigenetic modifications. Methylases, demethylases and histone deacetylase are deregulated in GSCs, allowing them to unlock transcriptional programs that are necessary for cell survival and plasticity. In this review, we described the effects of GSCs plasticity on GBM progression, discussing the role of GSCs niches on modulating their phenotype. Finally, we described epigenetic alterations in GSCs that are important for stemness, cell fate and therapeutic resistance.
RESUMO
Oxidative stress has been linked to the podocytopathy, mesangial expansion and progression of diabetic nephropathy. The major cell defence mechanism against oxidative stress is reduced glutathione (GSH). Some ABC transporters have been shown to extrude GSH, oxidised glutathione or their conjugates out of the cell, thus implying a role for these transporters in GSH homeostasis. We found a remarkable expression of mRNA for multidrug resistance-associated proteins (MRP/ABCC) 1, 3, 4 and 5 in rat glomeruli. Three weeks after induction of diabetes in glomeruli of streptozotocin-treated rats, we observed a decline in reduced GSH levels and an increase in the expression and activity of MRP1 (ABCC1). These lower GSH levels were improved by ex vivo treatment with pharmacological inhibitors of MRP1 activity (MK571). We conclude that increased activity of MRP1 in diabetic glomeruli is correlated with an inadequate adaptive response to oxidative stress.
Assuntos
Diabetes Mellitus Experimental/genética , Glomérulos Renais/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Glutationa/metabolismo , Masculino , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Propionatos/farmacologia , Quinolinas/farmacologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estreptozocina , Relação Estrutura-AtividadeRESUMO
Glioblastoma multiforme (GBM) is a brain tumour characterised by a remarkably high chemoresistance and infiltrating capability. To date, chemotherapy with temozolomide has contributed only poorly to improved survival rates in patients. One of the most important mechanisms of chemoresistance comes about through the activity of certain proteins from the ATP-binding cassette superfamily that extrudes antitumour drugs, or their metabolites, from cells. We identify an increased expression of the multiple drug resistance-associated protein 1 (Mrp1) in glioblastoma multiforme biopsies and in T98G and G44 cell lines. The activity of this transporter was also confirmed by measuring the extrusion of the fluorescent substrate CFDA. The sensitivity of GBM cells was low upon exposure to temozolomide, vincristine and etoposide, with decreases in cell viability of below 20% seen at therapeutic concentrations of these drugs. However, combined exposure to vincristine or etoposide with an inhibitor of Mrp1 efficiently decreased cell viability by up to 80%. We conclude that chemosensitization of cells with inhibitors of Mrp1 activity might be an efficient tool for the treatment of human GBM.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Neoplasias Encefálicas/patologia , Criança , Quimioterapia Combinada , Etoposídeo/farmacologia , Etoposídeo/uso terapêutico , Glioblastoma/patologia , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Vincristina/farmacologia , Vincristina/uso terapêuticoRESUMO
BACKGROUND: Mortality rate is dramatically high in high grade brain tumors. The presence of multiple drug resistance transporters in glioblastoma multiforme, has contributed largely to the poor efficacy of targeted therapy against cancer in the central nervous system. AIM: To analyze the percentage of survival and mortality of patients with glioblastoma multiforme in a cohort of patients in Chile and to co-rrelate the chemo-resistance of these cells with the expression level of multiple drug resistance transporters. MATERIALS AND METHODS: Eighteen biopsies of glioblastoma multiforme were obtained from patients at the Institute of Neurosurgery Dr. Asenjo (INCA). The tumor cells were obtained from primary cultures and the expression and activity of multiple drug resistance transporters was assessed by RT-PCR and immunohistochemistry. Population-based study was performed using the databases of the Department of Neurosurgery of INCA. RESULTS: The number of patients with glioblastoma multiforme increased between 2007 and 2009, from 3.5% to 7.9% of total brain tumors. Mortality of these tumors is 90 % at three years. A high expression and activity of the multiple drugs resistance associated protein 1 (Mrp1) transporter was observed in primary cultures of biopsies. CONCLUSIONS: We propose that Mrp1 activity is responsible for the chemo-resistance of the glioblastoma multiforme and inhibition of this transporter could represent a plausible strategy for the treatment.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Células Tumorais Cultivadas , Adulto JovemRESUMO
Gallbladder cancer (GBC) is an aggressive and highly lethal disease with relatively low global incidence, but one that constitutes a major health problem in Asian and Latin American countries, particularly in Chile. The identification of new tumor-associated markers with potential prognosis value is required for GBC clinical practice. Using immunohistochemistry/tumor tissue microarray, we evaluated the expression of 17 gastrointestinal tumor-associated protein markers (CK7, CK17, CK19, CK20, CKLMW, CKHMW, MUC1, MUC2, MUC5AC, MUC6, CA125, CD10, CEA, vimentin, villin, claudin-4, and CDX2) in primary gallbladder adenocarcinomas from 180 Chilean patients and analyzed potential associations with their pathological and clinical characteristics. Younger female patients with well- to moderately differentiated tumors had a better prognosis than that of older female or male patients with tumors with a similar tumor differentiation grade. Among all analyzed markers, MUC6 expression was associated with better prognosis in patients with well- to moderately differentiated tumors, whereas CK17 or CD10 was associated with worse prognosis in patients with poorly differentiated tumors. In addition, the MUC6+CK17- expression pattern was strongly associated with better prognosis in patients with well- to moderately differentiated tumors, whereas patients with poorly differentiated tumors and with the CK17+CD10+ expression pattern showed worse prognosis. Our results suggest that tumor MUC6, CK17, and CD10 can be considered as potential prognosis markers for GBC.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Diabetic nephropathy (DN) is considered the main cause of kidney disease in which myofibroblasts lead to renal fibrosis. Macrophages were recently identified as the major source of myofibroblasts in a process known as macrophage-myofibroblast transition (MMT). Adenosine levels increase during DN and in vivo administration of MRS1754, an antagonist of the A2B adenosine receptor (A2BAR), attenuated glomerular fibrosis (glomerulosclerosis). We aimed to investigate the association between A2BAR and MMT in glomerulosclerosis during DN. Kidneys/glomeruli of non-diabetic, diabetic, and MRS1754-treated diabetic (DM+MRS1754) rats were processed for histopathologic, transcriptomic, flow cytometry, and cellular in vitro analyses. Macrophages were used for in vitro cell migration/transmigration assays and MMT studies. In vivo MRS1754 treatment attenuated the clinical and histopathological signs of glomerulosclerosis in DN rats. Transcriptomic analysis demonstrated a decrease in chemokine-chemoattractants/cell-adhesion genes of monocytes/macrophages in DM+MRS1754 glomeruli. The number of intraglomerular infiltrated macrophages and MMT cells increased in diabetic rats. This was reverted by MRS1754 treatment. In vitro cell migration/transmigration decreased in macrophages treated with MRS1754. Human macrophages cultured with adenosine and/or TGF-ß induced MMT, a process which was reduced by MRS1754. We concluded that pharmacologic blockade of A2BAR attenuated some clinical signs of renal dysfunction and glomerulosclerosis, and decreased intraglomerular macrophage infiltration and MMT in DN rats.
Assuntos
Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Macrófagos/patologia , Monócitos/patologia , Miofibroblastos/patologia , Receptor A2B de Adenosina/metabolismo , Acetamidas/farmacologia , Antagonistas do Receptor A2 de Adenosina/farmacologia , Animais , Biomarcadores/metabolismo , Moléculas de Adesão Celular/metabolismo , Quimiocinas/metabolismo , Fatores Quimiotáticos/farmacologia , Fibrose , Humanos , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Purinas/farmacologia , Ratos Sprague-Dawley , Transcrição Gênica/efeitos dos fármacosRESUMO
Progressive diabetic nephropathy (DN) and loss of renal function correlate with kidney fibrosis. Crosstalk between TGF-ß and adenosinergic signaling contributes to the phenotypic transition of cells and to renal fibrosis in DN models. We evaluated the role of TGF-ß on NT5E gene expression coding for the ecto-5`-nucleotidase CD73, the limiting enzyme in extracellular adenosine production. We showed that high d-glucose may predispose HK-2 cells towards active transcription of the proximal promoter region of the NT5E gene while additional TGF-ß results in full activation. The epigenetic landscape of the NT5E gene promoter was modified by concurrent TGF-ß with occupancy by the p300 co-activator and the phosphorylated forms of the Smad2/3 complex and RNA Pol II. Transcriptional induction at NT5E in response to TGF-ß was earlier compared to the classic responsiveness genes PAI-1 and Fn1. CD73 levels and AMPase activity were concomitantly increased by TGF-ß in HK-2 cells. Interestingly, we found increased CD73 content in urinary extracellular vesicles only in diabetic patients with renal repercussions. Further, CD73-mediated AMPase activity was increased in the urinary sediment of DN patients. We conclude that the NT5E gene is a target of the profibrotic TGF-ß cascade and is a traceable marker of progressive DN.
Assuntos
5'-Nucleotidase/genética , Nefropatias Diabéticas/genética , Fibrose/genética , Fator de Crescimento Transformador beta/genética , Adenosina/biossíntese , Biomarcadores/metabolismo , Linhagem Celular , Nefropatias Diabéticas/patologia , Proteína p300 Associada a E1A/genética , Epigênese Genética/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibrose/patologia , Proteínas Ligadas por GPI/genética , Regulação da Expressão Gênica , Humanos , Rim/metabolismo , Rim/patologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Nucleotidases/genética , Regiões Promotoras Genéticas/genética , RNA Polimerase II/genéticaRESUMO
Glioblastoma (GBM) is the most devastating and least treatable brain tumor with median survival <15 months and extremely high recurrence rates. Promising results of immune checkpoint blockade obtained from pre-clinical studies in mice did not translate to clinic, and new strategies are urgently needed, particularly those targeting GBM stem cells (GSCs) that are held responsible for drug resistance and tumor recurrence. Patient-derived GSC cultures are critical for finding effective brain tumor therapies. Here, we investigated the ability of the recently described monoclonal antibody Nilo1 to specifically recognize GSCs isolated from GBM surgical samples. We employed five patient-derived GSC cultures with different stemness marker expression and differentiation potential, able to recapitulate original tumors when xenotransplanted in vivo. To answer whether Nilo1 has any functional effects in patient-derived GSCs lines, we treated the cells with Nilo1 in vitro and analyzed cell proliferation, cell cycle, apoptosis, sphere formation, as well as the expression of stem vs. differentiation markers. All tested GSCs stained positively for Nilo1, and the ability of Nilo1 to recognize GSCs strongly relied on their stem-like phenotype. Our results showed that a subset of patient-derived GSCs were sensitive to Nilo1 treatment. In three GSC lines Nilo1 triggered differentiation accompanied by the induction of p21. Most strikingly, in one GSC line Nilo1 completely abrogated self-renewal and led to Bax-associated apoptosis. Our data suggest that Nilo1 targets a molecule functionally relevant for stemness maintenance and pinpoint Nilo1 as a novel antibody-based therapeutical strategy to be used either alone or in combination with cytotoxic drugs for GSC targeting. Further pre-clinical studies are needed to validate the effectiveness of GSC-specific Nilo1 targeting in vivo.
RESUMO
Glioblastoma multiforme is one of the most malignant types of cancer. This is mainly due to a cell subpopulation with an extremely aggressive potential, called glioblastoma stem-like cells (GSCs). These cells produce high levels of extracellular adenosine which has been associated with increased chemoresistance, migration, and invasion in glioblastoma. In this study, we attempted to elucidate the mechanisms that control extracellular adenosine levels in GSC subtypes. By using primary and U87MG-derived GSCs, we associated increased extracellular adenosine with the mesenchymal phenotype. [3H]-adenosine uptake occurred mainly through the equilibrative nucleoside transporters (ENTs) in GSCs, but mesenchymal GSCs have lower expression and ENT1-mediated uptake activity than proneural GSCs. By analyzing expression and enzymatic activity, we determined that ecto-5'-nucleotidase (CD73) is predominantly expressed in proneural GSCs, driving AMPase activity. While in mesenchymal GSCs, both CD73 and Prostatic Acid Phosphatase (PAP) contribute to the AMP (adenosine monophosphate) hydrolysis. We did not observe significant differences between the expression of proteins involved in the metabolization of adenosine among the GCSs subtypes. In conclusion, the lower expression and activity of the ENT1 transporter in mesenchymal GSCs contributes to the high level of extracellular adenosine that these GSCs present.