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INTRODUCTION: Research in tumor treatment has shown promising results using extracellular vesicles (EVs) derived from immune cells. EVs derived from M1 macrophages (proinflammatory), known as M1-EVs, have properties that suppress tumor growth, making them a promising treatment tool for immune susceptible tumors such as melanoma. Here, small unaltered M1-EVs (M1-sEVs) were employed in a 3D mouse melanoma model (melanospheres) to evaluate such activity. METHODS: Macrophages were polarized and EVs were isolated by ultracentrifugation. The EVs obtained were characterized based on size, with measurements performed by dynamic light scattering and electron microscopy, and the expression profiles of microRNAs were analyzed by microarray and PCR. Melanospheres were used to evaluate the cytotoxicity of M1-sEVs. Pondering a possible future transposition from the animal model to the human, human melanoma cells were transfected with a specific miRNA, and the impact on cell proliferation was evaluated. RESULTS: The isolated EVs showed a size distribution between 50-400 nm in diameter, but preeminently in a range of 70-90 nm. M1-sEVs demonstrated a remarkable ability to reduce cell proliferation and viability in the melanospheres, leading to a decrease in their volume. M1-sEVs contained unique miRNAs, including miR-29a-3p, which exhibited significant antitumor activities according to bioinformatics analysis. Validation of the antitumor effects of miR-29a-3p was obtained by a functional evaluation, i.e., by inducing miRNA overexpression in human melanoma cells (SK-MEL-28). CONCLUSION: Although further research would be advisable, the study provides evidence supporting the potential of M1-sEVs and their miRNA load as a possible targeted immune therapy for melanoma.
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Vesículas Extracelulares , Melanoma , MicroRNAs , Animais , Humanos , Camundongos , Melanoma/terapia , Modelos Animais de Doenças , Macrófagos , MicroRNAs/genéticaRESUMO
Bone metastatic prostate cancer (PCa) is associated with a high risk of mortality. Changes in the expression pattern of miRNAs seem to be related to early aspects of prostate cancer, as well as its establishment and proliferation, including the necessary steps for metastasis. Here we compiled, for the first time, the important roles of miRNAs in the development, diagnosis, and treatment of bone metastasis, focusing on recent in vivo and in vitro studies. PCa exosomes are proven to promote metastasis-related events, such as osteoblast and osteoclast differentiation and proliferation. Aberrant miRNA expression in PCa may induce abnormal bone remodeling and support tumor development. Furthermore, miRNAs are capable of binding to multiple mRNA targets, a dynamic property that can be harnessed for the development of treatment tools, such as antagomiRs and miRNA mimics, which have emerged as promising candidates in PCa treatment. Finally, miRNAs may serve as noninvasive biomarkers, as they can be detected in tissue and bodily fluids, are highly stable, and show differential expression between nonmetastatic PCa and bone metastatic samples. Taken together, the findings underscore the importance of miRNA expression profiles and miRNA-based tools as rational technologies to increase the quality of life and longevity of patients.
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BACKGROUND: Considering that microRNAs (miRNAs), extracellular vesicles and particles (EVPs) and the amyloid precursor protein (APP) processing have been shown to be altered in oral squamous cells carcinoma (OSCC), it is possible that miRNAs that target APP processing pathways in EVPs are impacted in tumor cells. Our aim was to evaluate miRNAs that target APP itself or disintegrin and metalloproteinase domain 10 (ADAM10), which generate a trophic compound, sAPPα, in EVPs derived from OSCC cell lines, an aggressive and non-invasive, compared to normal keratinocytes. METHODS: We used two OSCC cell lines, an aggressive human oral squamous cell carcinoma cell line (SCC09) and a less aggressive cell line (CAL27) compared with a keratinocyte lineage (HaCaT). Cells were maintained in cell media, from which we isolated EVPs. EVPs were evaluated regarding their size and concentration using Nanotracking Analysis. We measured the levels of miRNAs which had as potential downstream target APP or ADAM10, specifically miR-20a-5p, miR-103a-3p, miR-424-5p, miR-92b-3p, miR-31-5p, and miR-93-5. RESULTS: There were no differences on size distributions and concentration of isolated EVPs. OSCC cell lines-derived EVPs miR-20a-5p, miR-92b-3p, and miR-93-5p were upregulated in comparison to HaCaT-derived EVPs; while miR-31-5p was reduced in EVPs obtained from CAL27 cells. CONCLUSION: Our results indicate changes in miRNAs that target APP machinery processing in EVPs derived from OSCC cell lines of different aggressiveness, which may be involved with abnormal miRNA expression in OSCC tissue and/or releasing tumor suppressor miRNA.
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Carcinoma de Células Escamosas , Vesículas Extracelulares , Neoplasias de Cabeça e Pescoço , MicroRNAs , Neoplasias Bucais , Humanos , MicroRNAs/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Neoplasias Bucais/patologia , Neoplasias de Cabeça e Pescoço/genética , Células Epiteliais/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genéticaRESUMO
Acanthamoeba spp. are the causative agents of a sight-threatening infection of the cornea known as Acanthamoeba keratitis (AK). Amphotericin B - deoxycholate (AB) is used in the treatment of infectious keratitis, however, its topical administration has side effects as blepharitis, iritis, and painful instillation. In this context, the preheating of AB can decrease its toxicity by the formation of super aggregates (hAB). hAB associated with a thermoreversible in situ gelling ophthalmic system is a promising option due to the latter biocompatibility, low toxicity, and high residence time on the ocular surface. Our objective was to develop a topical ocular formulation of hAB for the treatment of AK. After heating at 70°C for 20 min, hAB was incorporated into a thermoreversible gelling system. The amebicidal activity of AB and hAB was evaluated against trophozoites and cysts of A. castellanii (ATCC 50492) and a regional clinical isolate (IC01). The results showed that the preheating of AB did not change the pharmacological action of the drug, with the amebicidal effect of AB and hAB under trophozoites and cysts of Acanthamoeba spp. The thermoreversible system remained stable, allowing the increase of drug retention time. For assessment of cytotoxicity, HUVEC (ATCC® CRL-1730) cells were challenged with AB and hAB for 48h. Cell viability was assessed, and hAB did not show cytotoxicity for HUVEC cells. As far as we know this was the first study that showed the preheated AB associated with a thermoreversible in situ gelling ophthalmic system as a promising system for topical ocular topical administration of hAB for AK therapy.
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Ceratite por Acanthamoeba , Acanthamoeba , Amebicidas , Ceratite por Acanthamoeba/tratamento farmacológico , Amebicidas/farmacologia , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Animais , TrofozoítosRESUMO
The progression to a castration-resistant prostate cancer can occur after treatment with androgen deprivation therapy, resulting in poor prognosis and ineffective therapy response. Hormone dependence transition has been associated with increased tumor vascularization. Considering that exosomes are important components in communication between tumor cells and the microenvironment, we examined the angiogenic potential of exosomes released from Pca cell lines with distinctive profiles of androgen response through exosomes isolation, microscopy and uptake, functional assays follow up by microarray, RT-qPCR and bioinformatics analysis. HUVEC cells treated with PC-3 exosomes (androgen independent) showed increased invasion and tube formation ability. In order to identify microRNAs (miRNAs) related to the angiogenic response, the characterization of exosomal miRNA profile was performed. As result we suggest that the miR-27a-3p could be involved in the pro-angiogenic effect of PC-3 exosomes.
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Exossomos , MicroRNAs , Neoplasias da Próstata , Antagonistas de Androgênios/metabolismo , Linhagem Celular Tumoral , Exossomos/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/patologia , Microambiente TumoralRESUMO
Prostate cancer-related deaths are mostly caused by metastasis, which indicates the importance of identifying clinical prognostic biomarkers. In this study, we evaluated the expression profile of exosomal microRNAs (miRNAs) derived from metastatic prostate cancer (mPCa) cell lines (LNCaP and PC-3). miRNA signatures in exosomes and cells were evaluated by miRNA microarray analysis. Fourteen miRNAs were identified as candidates for specific noninvasive biomarkers. The expression of five miRNAs was validated using RT-qPCR, which confirmed that miR-205-5p, miR-148a-3p, miR-125b-5p, miR-183-5p, and miR-425-5p were differentially expressed in mPCa exosomes. Bioinformatic analyses showed that miR-425-5p was associated with residual tumor, pathologic T and N stages, and TP53 status in PCa samples. Gene ontology analysis of negatively correlated and predicted targeted genes showed enrichment of genes related to bone development pathways. The LinkedOmics database indicated that the potential target HSPB8 has a significant negative correlation with miR-425-5p. In conclusion, this study identified a panel of exosomal miRNAs with potential value as prognostic biomarkers for prostate cancer.
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Exossomos , MicroRNAs , Neoplasias da Próstata , Biomarcadores/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biologia Computacional , Exossomos/genética , Exossomos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/patologiaRESUMO
There is a consensus regarding the efficacy of physical exercise in maintaining or improving human health; however, there are few studies examining the effect of physical exercise on the expression levels of microRNAs (miRNA/miRs) in Parkinson's disease (PD). The aim of the present study was to investigate the effects of an interval training program on a cycle ergometer on the expression levels of miR106a5p, miR103a3p and miR29a3p in serum samples from men with PD. This was a quasiexperimental study with pre and posttesting and with a nonequivalent group design. The participants were selected based on the eligibility criteria and subsequently classified into two groups: Experimental group and control group. The evaluations were performed at the beginning of the study (week 0) and after 8 weeks of the intervention program (week 9). The interval training program was performed on a cycle ergometer for 30 min, three times a week during an 8week period. The expression levels of miR106a5p, miR103a3p and miR29a3p in the experimental group were increased after physical exercise and were associated with cognitive improvement in men with PD. However, further studies are required to clarify the potential use of these circulating miRNAs as markers of adaptation to physical exercise. Collectively, the present results indicated that these three miRNAs may be associated with the exercise response and cognitive improvement in men with PD.
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Cognição/fisiologia , Terapia por Exercício/métodos , Exercício Físico/fisiologia , MicroRNAs/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/terapia , Idoso , Correlação de Dados , Regulação da Expressão Gênica , Humanos , Masculino , Testes de Estado Mental e Demência , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , Doença de Parkinson/metabolismo , Teste de CaminhadaRESUMO
BACKGROUND: The use of RNA interference (iRNA) therapy has proved to be an interesting target therapy for the cancer treatment; however, siRNAs are unstable and quickly eliminated from the bloodstream. To face these barriers, the use of biocompatible and efficient nanocarriers emerges as an alternative to improve the success application of iRNA to the cancer, including breast cancer. RESULTS: A hybrid nanocarrier composed of calcium phosphate as the inorganic phase and a block copolymer containing polyanions as organic phase, named HNPs, was developed to deliver VEGF siRNA into metastatic breast cancer in mice. The particles presented a rounded shape by TEM images with average size measured by DLS suitable and biocompatible for biomedical applications. The XPS and EDS spectra confirmed the hybrid composition of the nanoparticles. Moreover, after intravenous administration, the particles accumulated mainly in the tumor site and kidneys, which demonstrates the tumor targeting accumulation through the Enhanced Permeability and Retention Effect (EPR). A significant decrease in size of the tumors treated with the nanoparticles containing siVEGF (HNPs-siVEGF) was observed and the reduction was related to enhanced tumor accumulation of siRNA as well as in vivo VEGF silencing at gene and protein levels. CONCLUSION: The hybrid system prepared was successful in promoting the RNAi effect in vivo with very low toxicity. GENERAL SIGNIFICANCE: This study shows the valuable development of a hybrid nanoparticle carrying VEGF siRNA, as well as their tumor targeting, accumulation and reduction in mice triple-negative breast cancer.
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Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Nanopartículas/química , RNA Interferente Pequeno/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , RNA Interferente Pequeno/química , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Jungia sellowii Less. (Asteraceae) is a native plant found in Southeast Brazil used traditionally to treat inflammatory diseases. This study was conducted (1) to investigate the toxicity of the crude extract (CE) and (2) to investigate the mechanism of the anti-inflammatory action of J. sellowii L. roots. The potential acute toxicity of CE was performed by administration of only different doses of CE (500, 1,000, and 2,000 i.p.) on mice for 14 days. The anti-inflammatory effect was evaluated using carrageenan-induced acute pleural cavity inflammation in a mouse model, evaluated through the following inflammatory variables: leukocyte, protein concentrations of the exudate, myeloperoxidase (MPO), adenosine deaminase (ADA), nitric oxide metabolites (NOx), and proinflammatory cytokine (tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), interleukin- (IL-) 6, and IL-12) levels in mouse pleural fluid leakage. The p65 protein phosphorylation of nuclear factor NF-kappa B (p65 NF-κB) and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation were analyzed in lung tissue. Our results demonstrated that the administration of CE up to 2,000 mg/kg did not present a toxic effect. In addition, the pretreatment of mice with CE; its derived fractions (aqueous fraction (AqF), butanol fraction (BuOHF), and ethyl acetate fraction (EtOAcF)); and isolated compounds (curcuhydroquinone O-ß-glucose (CUR) and α and ß piptizol (Pip)) reduced the following inflammatory variables: neutrophils, protein concentrations of the exudate, MPO, ADA, NOx, and proinflammatory cytokine (TNF-α, IFN-γ, IL-6, and IL-12) levels in mouse pleural fluid leakage. The compounds CUR and Pip also decreased the p65 protein phosphorylation of NF-kappa B and p38 (MAPK) in lung tissue. J. sellowii L. has important anti-inflammatory activity with potential applications in drug development against inflammatory disorders. These effects found can be attributed to the ability of the new isolated compounds CUR and Pip to suppress p65 NF-κB and p-p38 MAPK pathways.
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Anti-Inflamatórios/farmacologia , Asteraceae , Mediadores da Inflamação/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Extratos Vegetais/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Adenosina Desaminase/metabolismo , Animais , Asteraceae/química , Células Cultivadas , Regulação para Baixo , Feminino , Mediadores da Inflamação/análise , Camundongos , Extratos Vegetais/toxicidade , Transdução de Sinais/efeitos dos fármacosRESUMO
Acute-on-chronic liver failure (ACLF) is a condition characterized by acute decompensation of cirrhosis, associated with organ failure(s), and high short-term mortality. The microRNAs or miRNAs are small non-coding RNA molecules, stable in circulating samples such as biological fluids, and the difference in expression levels may indicate the presence, absence and/or stage of the disease. We analyzed here the miRNA profiling to identify potential diagnostic or prognostic biomarkers for ACLF. The major miRNAs discovered were validated in a cohort of patients with acute decompensation of cirrhosis grouped in no ACLF or ACLF according to EASL-CLIF definition. Relationship between serum miRNAs and variables associated with liver-damage and survival outcomes were verified to identify possible prognostic markers. Our results showed twenty altered miRNAs between no ACLF and ACLF patients, and twenty-seven in patients who died in 30 days compared with who survived. In validation phase, miR-223-3p and miR-25-3p were significantly altered in ACLF patients and in those who died in 30 days. miR-223-3p and miR-25-3p expression were associated with the lowest survival in 30 days. The decrease in miR-223-3p and miR-25-3p expression was associated with the presence of ACLF and poor prognosis. Of these, miR-25-3p was independently related to ACLF and 30-day mortality.
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Insuficiência Hepática Crônica Agudizada/mortalidade , Biomarcadores/sangue , Cirrose Hepática/mortalidade , MicroRNAs/genética , Insuficiência Hepática Crônica Agudizada/sangue , Insuficiência Hepática Crônica Agudizada/genética , Insuficiência Hepática Crônica Agudizada/patologia , Estudos de Casos e Controles , Feminino , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Prognóstico , Curva ROC , Índice de Gravidade de Doença , Taxa de SobrevidaRESUMO
In a previous study, we described a series of 28 aryl- and alkyl-substituted isothiouronium salts with antitumor activity and selectivity toward a leukemia cell line. Among the synthesized compounds, methyl (Z)-2-(isothioureidomethyl)-2-pentenoate hydrobromide (IS-MF08) showed conspicuous activity. In the present study, we investigated the mechanism of action of IS-MF08. Our results showed that its mechanism most likely is related with the membrane receptor Fas and subsequent activation of the extrinsic cell death pathway, triggered by a decrease in the levels of the anti-apoptotic protein Bcl-2 and caspase-8 and -3 cascade activation, causing DNA damage and mitotic arrest. IS-MF08 also caused an increase in intracellular ROS, endoplasmic reticulum (ER) stress, and mitochondrial membrane permeabilization, resulting in organelle degradation as an attempt to reestablish cell homeostasis. Furthermore, cells exposed to IS-MF08 combined to an autophagy inhibitor were less susceptible to compound's cytotoxicity, suggesting that autophagy makes part of its mechanism of action. These data support the hypothesis that IS-MF08 acts by the apoptosis extrinsic pathway and possibly by autophagy as mechanisms of cell death.
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Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Isotiurônio/farmacologia , Leucemia/patologia , Mitose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacosRESUMO
Short interfering RNA (siRNA) showed to be a viable alternative to a better prognosis in cancer therapy. Nevertheless, the successful application of this strategy still depends on the development of nanocarriers for the safe delivery of siRNA into the diseased tissue, which mostly occurs by passive accumulation. When an external magnetic field is applied, magnetic nanoparticles biodistribution is partially modulated to favor accumulation in a target tissue. In this work we designed a novel magnetic responsive siRNA nanocarrier. The new delivery system is composed of superparamagnetic iron oxide nanoparticles (SPIONs) coated with calcium phosphate (CaP) and PEG-polyanion block copolymers, which are known to be biocompatible. The nanoparticles presented rounded shape with small size and narrow distribution suitable for biomedical applications. TEM images showed dark spheres in the core surrounded by a lower electron density material in the corona. The X-ray photoelectron spectra (XPS) confirmed CaP-polymer coating of the magnetic core. In addition, the coating procedure did not affect the superparamagnetic property as showed using a vibrating sample magnetometer (VSM). With a high loading efficiency (80%), the nanoparticles enhanced vascular endothelium growth factor (VEGF) silencing in breast cancer cells in vitro, at gene and protein levels (~60% and 40%, respectively), without associated toxicity. Iron and siRNA quantification showed that the novel nanoparticles move towards a magnetic source carrying siRNA molecules. Therefore, these novel nanoparticles are a promising tool for cancer therapy based on RNAi effect, added by a magnetic capability to further modulate siRNA accumulation in the target tissue.
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Neoplasias da Mama/metabolismo , Magnetismo , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Inativação Gênica , Humanos , Campos Magnéticos , Nanopartículas/ultraestrutura , Tamanho da Partícula , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Glioblastoma is the most common and aggressive glioma, characterized by brain invasion capability. Being very resistant to the current therapies, since even under treatment, surgery, and chemotherapy with temozolomide (TMZ), patients achieve a median survival of one year. In the search for more effective therapies, new molecules have been designed. For nervous system cancers, molecules able to cross the blood-brain barrier are handled with priority. Accordingly, tacrine was chosen for this study and the inclusion of spiro-heterocyclic rings was done in its structure resulting in new compounds. Cytotoxic activity of tacrine derivatives was assayed using glioblastoma cell line (SF295) as well as analyzing cell death mechanism. Increased caspases activities were observed, confirming apoptosis as cell death type. Some derivatives also increased reactive oxygen species formation and decreased the mitochondrial membrane potential. Moreover, compounds acted on several glioblastoma-related proteins including p53, HLA-DR, beta-catenin, Iba-1, MAP2c, Olig-2, and IDH1. Therefore, tacrine derivatives presented promising results for the development of new glioblastoma therapy, particularly to treat those patients resistant to TMZ.
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Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Proteínas de Neoplasias/fisiologia , Tacrina/farmacologia , Apoptose/efeitos dos fármacos , Caspases/fisiologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitose/efeitos dos fármacos , Estrutura Molecular , Terapia de Alvo Molecular , Necrose , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Espécies Reativas de Oxigênio/metabolismo , Tacrina/análogos & derivados , TemozolomidaRESUMO
The present study characterized propolis extracts produced by Scaptotrigona bipunctata (Tubuna) and Melipona quadrifasciata (Mandaçaia) by LC-MS/MS; their cytotoxicity as well as the mechanism of action in a melanoma cellular model were also assessed. The chemical characterization performed by UPLC-ESI-QTOF/MS2 analysis revealed uncommon presence of piperidinic alkaloids in Tubuna's propolis extract together with C-glycopyranoside flavonoids. Mandaçaia's propolis collected in the same area rather presented terpenoids and flavonoids. Regarding the mechanism of cytotoxicity, propolis extracts increased the accumulation of reactive oxygen species (ROS), reduced the potential of mitochondrial membrane, induced a decrease in the proteins Bcl-2 and AKT-3 levels, and decreased melanoma cells' migration and invasion. Both propolis extracts induced apoptosis while only Mandaçaia's propolis extract induced cell cycle arrest in G2/M.
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Apoptose/efeitos dos fármacos , Melanoma/tratamento farmacológico , Própole/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Alcaloides/química , Alcaloides/farmacologia , Animais , Abelhas/fisiologia , Brasil , Linhagem Celular Tumoral , Movimento Celular , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Piperidinas/química , Piperidinas/farmacologia , Própole/química , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodosRESUMO
Tumorigenesis is related to an imbalance in controlling mechanisms of apoptosis. Expression of the genes BCL-2 and BCL-xL results in the promotion of cell survival by inhibiting apoptosis. Thus, a novel approach to suppress antiapoptotic genes is the use of small interfering RNA (siRNA) in cancer cells. However, there are some limitations for the application of siRNA such as the need for vectors to pass the cell membrane and deliver the nucleic acid. In this study CaP-siRNA-PEG-polyanion hybrid nanoparticles were developed to promote siRNA delivery to cultured human breast cancer cells (MCF-7) in order to evaluate whether the silencing of antiapoptotic genes BCL-2 and BCL-xL by siRNA would increase cancer cell death. After 48 h of incubation the expression of BCL-2 and BCL-xL genes decreased to 49% and 23%, respectively. The siRNA sequence used induced cancer cell death at a concentration of 200 nM siRNA after 72 h of incubation. As the targeted proteins are related to the resistance to chemotherapeutic drugs, the nanocarriers systems were also tested in the presence of doxorubicin (DOX). The results showed a significant reduction in the CC50 of the DOX, after silencing the antiapoptotic genes. In addition, an increase in apoptotic cell counts for both incubations conditions was observed as well. In conclusion, silencing antiapoptotic genes such as BCL-2 and BCL-xL through the use of siRNA carried by hybrid nanoparticles showed to be effective in vitro, and presents a promising strategy for pre-clinical analysis, especially when combined with DOX against breast cancer.
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Apoptose/genética , Neoplasias da Mama/terapia , Nanopartículas/uso terapêutico , RNA Interferente Pequeno/administração & dosagem , Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Sobrevivência Celular/genética , Doxorrubicina/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Nanopartículas/administração & dosagem , Nanopartículas/química , Polietilenoglicóis/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismoRESUMO
A series of 28 aryl- and alkyl-substituted isothiouronium salts were readily synthesized in high yields through the reaction of allylic bromides with thiourea, N-monosubstituted thioureas or thiosemicarbazide. The S-allylic isothiouronium salts substituted with aliphatic groups were found to be the most effective against leukemia cells. These compounds combine high antitumor activity and low toxicity toward non-tumoral cells, with selectivity index higher than 20 in some cases. Furthermore, the selected isothiouronium salts induced G2/M cell cycle arrest and cell death, possibly by apoptosis. Therefore, these compounds can be considered as a promising class of antitumor agents due to the potent cytostatic activity associated with high selectivity.
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Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Isotiurônio/síntese química , Isotiurônio/farmacologia , Tioureia/análogos & derivados , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Humanos , Relação Estrutura-AtividadeRESUMO
In light of the evidence that in contrast to most healthy tissues, several neoplasms overexpress fatty acid synthase (FASN) upon their dependence on increased lipogenesis; targeting of this protein is being considered as a valuable strategy in anticancer drug development. This can be particularly relevant for aggressive tumors such as melanoma in which FASN overexpression has been associated with increased depth of invasion and worse prognosis. We have previously shown that a sub-class of cyclic imides, the N-phenylmaleimides, presented antitumor activity against L1210 leukemia and B16F10 melanoma with evidences of interference in the energetic metabolism. Here, we aimed to investigate if some selected N-phenylmaleimides (M1 and M5) interfere with fatty acids metabolism and its relation with cancer. For that, a model of pre-adipocytes differentiation (3T3-L1 cells) and also human melanoma cells (SK-Mel-147) were used. As results, when 3T3-L1 cells were exposed to non-cytotoxic concentrations of M1 and M5 in the presence of an adipogenic cocktail, intracellular lipid content decreased by 26-36%, marking the inhibition of adipocyte differentiation. High selectivity indexes were obtained for both compounds for tumoral cells. Cell cycle phases analysis revealed a remarkable proportion of cells with DNA fragmentation after their exposure to M1 and M5. This was correlated to both apoptosis and necrosis, showed by Annexin-V/PI assay. Furthermore, M1 and M5 reduced FASN expression by 19-39%, respectively. In conclusion, M1 and M5 presented antiadipogenic and antitumoral activities. The antitumoral activity that was associated to apoptosis and necrosis is a possible consequence of the FASN reduction, which in turn, might result in a fuel decrease to cell proliferation. As it happens with antiangiogenic activity, reduction of fatty acid synthesis might be a potential target for cancer treatment in a strategy of hunger-strike, which valorizes these N-phenylmaleimides as candidates for drug development.
Assuntos
Adipogenia/efeitos dos fármacos , Antineoplásicos/farmacologia , Ácido Graxo Sintases/genética , Maleimidas/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ácido Graxo Sintases/metabolismo , Citometria de Fluxo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Maleimidas/química , CamundongosRESUMO
Nine types of solid lipid nanoparticle (SLN) formulations were produced using tripalmitin (TPM), glyceryl monostearate (GM) or stearic acid (SA), stabilized with lecithin S75 and polysorbate 80. Formulations were prepared presenting PI values within 0.25 to 0.30, and the physicochemical properties, stability upon storage and biocompatibility were evaluated. The average particle size ranged from 116 to 306 nm, with a negative surface charge around -11 mV. SLN presented good stability up to 60 days. The SLN manufactured using SA could not be measured by DLS due to the reflective feature of this formulation. However, TEM images revealed that SA nanoparticles presented square/rod shapes with an approximate size of 100 nm. Regarding biocompatibility aspects, SA nanoparticles showed toxicity in fibroblasts, causing cell death, and produced high hemolytic rates, indicating toxicity to red blood cells. This finding might be related to lipid type, as well as, the shape of the nanoparticles. No morphological alterations and hemolytic effects were observed in cells incubated with SLN containing TPM and GM. The SLN containing TPM and GM showed long-term stability, suggesting good shelf-life. The results indicate high toxicity of SLN prepared with SA, and strongly suggest that the components of the formulation should be analyzed in combination rather than separately to avoid misinterpretation of the results.
Assuntos
Lipídeos/química , Nanopartículas/toxicidade , Tensoativos/química , Animais , Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/ultraestrutura , Hemólise/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Células NIH 3T3 , Nanopartículas/química , Tamanho da PartículaRESUMO
A series of chalcones substituted by a quinoxaline unit at the B-ring were synthesized and tested as inhibitors of breast cancer resistance protein-mediated mitoxantrone efflux. These compounds appeared more efficient than analogs containing other B-ring substituents such as 2-naphthyl or 3,4-methylenedioxyphenyl while an intermediate inhibitory activity was obtained with a 1-naphthyl group. In all cases, two or three methoxy groups had to be present on the phenyl A-ring to produce a maximal inhibition. Molecular modeling indicated both electrostatic and steric positive contributions. A higher potency was observed when the 2-naphthyl or 3,4-methylenedioxyphenyl group was shifted to the A-ring and methoxy substituents were shifted to the phenyl B-ring, indicating preferences among polyspecificity of inhibition.
Assuntos
Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Chalconas/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Quinoxalinas/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Antineoplásicos/síntese química , Antineoplásicos/química , Células Cultivadas , Chalconas/síntese química , Chalconas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HEK293 , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Chalcones, naturally occurring open-chain flavonoids abundant in plants, have demonstrated anticancer activity in multiple tumor cells. In a previous work, the potential anticancer activity of three naphthylchalcones named R7, R13 and R15 was shown. In this study, the mechanism of actions of these chalcones was originally shown. The chalcones presented concentration and time-dependent cytotoxicity. To determine the type of cell death induced by chalcones, we assessed a series of assays including measurements of the caspase-8, -9 and -12 activities, expression of important apoptosis-related genes and proteins, changes in the cell calcium concentration and cytochrome c release. The activities of caspase-8, -9 and -12 increased after the treatment of L1210 cells with the three compounds. Chalcones R7 and R13 induced an increase of pro-apoptotic proteins Bax, Bid and Bak (only chalcone R13), as well as a decrease in anti-apoptotic Bcl-2 expression. These chalcones also induced an increase in Fas and a decrease in p21 and p53 expression. Chalcone R15 seems to act by a different mechanism to promote cell death, as it did not change the mitochondrion-related proteins, nor did it induce the cytochrome c release. All compounds induced an increase in cell calcium concentration and an increase in CHOP expression, which together with an increase in caspase-12 activity, suggest that chalcones could induce an endoplasmic reticulum (ER) stress. Taken together, these results suggest that chalcones induce apoptosis by different pathways, being an interesting strategy to suggest for cancer therapy.