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1.
Invest New Drugs ; 38(4): 1044-1055, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31781904

RESUMO

Gliomas account for nearly 70% of the central nervous system tumors and present a median survival of approximately 12-17 months. Studies have shown that administration of novel natural antineoplastic agents is been highly effective for treating gliomas. This study was conducted to investigate the antitumor potential (in vitro and in vivo) of Miconia chamissois Naudin for treating glioblastomas. We investigated the cytotoxicity of the chloroform partition and its sub-fraction in glioblastoma cell lines (GAMG and U251MG) and one normal cell line of astrocytes. The fraction showed cytotoxicity and was selective for tumor cells. Characterization of this fraction revealed a single compound, Matteucinol, which was first identified in the species M. chamissois. Matteucinol promoted cell death via intrinsic apoptosis in the adult glioblastoma lines. In addition, Matteucinol significantly reduced the migration, invasion, and clonogenicity of the tumor cells. Notably, it also reduced tumor growth and angiogenesis in vivo. Moreover, this agent showed synergistic effects with temozolomide, a chemotherapeutic agent commonly used in clinical practice. Our study demonstrates that Matteucinol from M chamissois is a promising compound for the treatment of glioblastomas and may be used along with the existing chemotherapeutic agents for more effective treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Cromonas/uso terapêutico , Glioblastoma/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Cromonas/isolamento & purificação , Cromonas/farmacologia , Glioblastoma/irrigação sanguínea , Humanos , Melastomataceae , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Extratos Vegetais , Folhas de Planta
2.
Mol Immunol ; 111: 172-181, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31063938

RESUMO

Great efforts have been made to identify promising antigens and vaccine formulations against schistosomiasis. Among the previously described Schistosoma vaccine candidates, cyclophilins comprise an interesting antigen that could be used for vaccine formulations. Cyclophilin A is the target for the cyclosporine A, a drug with schistosomicide activity, and its orthologue from Schistosoma japonicum induces a protective immune response in mice. Although Schistosoma mansoni cyclophilin A also represents a promising target for anti-schistosome vaccines, its potential to induce protection has not been evaluated. In this study, we characterized the cyclophilin A (SmCyp), initially described as Smp17.7, analyzed its allergenic potential using in vitro functional assays, and evaluated its ability to induce protection in mice when administered as an antigen using different vaccine formulations and strategies. Results indicated that SmCyp could be successfully expressed by mammalian cells and bacteria. The recombinant protein did not promote IgE-reporter system activation in vitro, demonstrating its probable safety for use in vaccine formulations. T and B-cell epitopes were predicted in the SmCyp sequence, with two of them located within the active isomerase site. The most immunogenic antigen, SmCyp (107-121), was then used for immunization protocols. Immunization with the SmCyp gene or protein failed to reduce parasite burden but induced an immune response that modulated the granuloma area. In contrast, immunization with the synthetic peptide SmCyp (107-121) significantly reduced worm burden (48-50%) in comparison to control group, but did not regulate liver pathology. Moreover, the protection observed in mice immunized with the synthetic peptide was associated with the significant production of antibodies against the SmCyp (107-121) epitope. Therefore, in this study, we identified an epitope within the SmCyp sequence that induces a protective immune response against the parasite, thus representing a promising antigen that could be used for vaccine formulation against schistosomiasis.


Assuntos
Ciclofilina A/imunologia , Epitopos/imunologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/imunologia , Antígenos de Helmintos/imunologia , Feminino , Proteínas de Helminto/imunologia , Imunização/métodos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/imunologia , Vacinação/métodos , Vacinas/imunologia
3.
Clin Oral Investig ; 23(4): 1913-1919, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30229300

RESUMO

OBJECTIVE: The aim of this study was to evaluate the immunohistochemical expressions of PD1, CD4+, and CD8+ in premalignant lesions (OPML) that were transformed into oral squamous cell carcinoma OSCC (OPML-OSCC), in OSCC and also in premalignant lesions that were not transformed into OSCC (OPML-NOSSC). MATERIALS AND METHODS: Retrospective analyses were performed in order to verify the demographic characteristics of the patients. CD4, CD8, and PD1 IMH studies were carried out on OPML and OSCC samples from 11 patients with OPML-OSCC and OPML, together with samples from 14 patients with OPML-NOSCC. The differences between OPML-OSCC and OPML-NOSCC were analyzed. RESULTS: Non-homogenous leukoplakia, together with the related oral subsite, and the lack of an exposure to tobacco, were all associated with malignant transformations. There were no statistical differences in the PD1 expression and the CD4+ cells in OPML-OSCC and OPML-NOSCC. A significant increment in the CD8+ cells was noted in the OPML that evolved into carcinomas when compared with OPML-NOSCC (p = 0.05), whereas there were higher CD8+ cells levels in the carcinomas when compared with the OPML that evolved into carcinomas (p = 0.027). CONCLUSIONS: CD8+ cells infiltrate more in OPML-NOSCC than in OPML-OSCC. Carcinoma is more infiltrated by CD8+ cells than its associated OPML. CLINICAL RELEVANCE: Understanding immunological factors associated with malignant transformation of oral premalignant lesions can open a new way to treat this disease.


Assuntos
Linfócitos T CD8-Positivos/citologia , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Lesões Pré-Cancerosas , Carcinoma de Células Escamosas/imunologia , Feminino , Humanos , Masculino , Neoplasias Bucais/imunologia , Estudos Retrospectivos
4.
Int Immunopharmacol ; 31: 123-31, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26724477

RESUMO

The leaves of Byrsonima verbascifolia (Malpighiaceae) are traditionally used to treat various diseases including inflammatory conditions. The main goal of this study was to evaluate the in vivo anti-inflammatory activity of the polar constituents from the butanolic fraction of B. verbascifolia leaves (BvBF), as well as to investigate the mechanisms involved in the anti-inflammatory activity. The polar constituents were identified by liquid chromatography coupled to diode array detector and mass spectrometry (LC-DAD­MS) and matrix-assisted laser desorption/ionization ­ time-of-flight mass spectrometry (MALDI-TOF MS) to obtain a complete chemical profile of the fraction. Forty-five compounds were detected in the BvBF by LC-DAD­MS/MS, including condensed tannins, phenolic acids, flavonoids (flavones and flavonols) and other compounds. In addition, several condensed tannins were identified by MALDI-MS/MS, which are composed predominantly by procyanidin units (PCY) and up to six flavan-3-ol units. The BvBF exhibited significant antioxidant and anti-inflammatory activities. The BvBF inhibited paw edema and polymorphonuclear (PMN) leukocyte migration to the footpad and pleural cavity induced by carrageenan. Furthermore, a minor dose (12.50 mg/kg) of BvBF effectively decreased tumor necrosis factor alpha (TNF-α) and prostaglandin E2 (PGE2) levels in the footpad. These findings suggest that the mechanism of the anti-inflammatory action in the BvBF is linked to the inhibition of the production of inflammatory mediators such as TNF-α and PGE2 and the PMN cell migration.


Assuntos
Anti-Inflamatórios não Esteroides/imunologia , Edema/tratamento farmacológico , Malpighiaceae/imunologia , Neutrófilos/efeitos dos fármacos , Extratos Vegetais/imunologia , Animais , Anti-Inflamatórios não Esteroides/química , Butanóis/química , Carragenina , Movimento Celular/efeitos dos fármacos , Dinoprostona/metabolismo , Edema/induzido quimicamente , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Extratos Vegetais/química , Folhas de Planta , Fator de Necrose Tumoral alfa/metabolismo
5.
Anticancer Res ; 34(10): 5397-403, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25275034

RESUMO

AIM: The present study evaluated the expression of α1 and ß1 Na,K-ATPase, as well as the effects of digoxin (DGX) on oral squamous cell carcinomas (OSCCs). PATIENTS AND METHODS: Immunohistochemical expression of α1 and ß1 Na,K-ATPase were evaluated in 60 patients who underwent treatment at the São João de Deus Hospital. SCC-25 viability was assessed by the colorimetric assay. Chi-square or Fisher's exact tests were used to analyze the association of α1 and ß1 Na,K-ATPase expression with the variables. RESULTS: Immunoexpression of α1 and ß1 Na,K-ATPase were observed in 28% and 55% of the tumors, however these proteins were not significant prognostic factors. Tobacco was significantly associated with α1 expression. SCC-25 viability decreased significantly after treatment with 1 µM DGX at 24 h. CONCLUSION: The smoking status of OSCC patients was significantly associated with α1 expression and DGX affected the SCC-25 viability in a dose- and duration-dependent manner.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Digoxina/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias Bucais/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Gradação de Tumores , Estadiamento de Neoplasias , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Fatores de Risco , ATPase Trocadora de Sódio-Potássio/genética
6.
Arch Oral Biol ; 57(8): 1026-33, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22727410

RESUMO

Oral squamous cell carcinoma (OSCC) corresponds to 95% of all malignant tumours of the mouth. The association between alcohol and tobacco is the major risk factor for this disease, increasing the chances for the development of OSCC by 35-fold. The plant, Cannabis sativa is smoked as cigarettes or blunts and is commonly used in association with tobacco and alcohol. Any type of smoking habit exposes individuals to a wide range of carcinogens or pro-carcinogens, such as polycyclic aromatic hydrocarbons, as well as some ethanol derived substances such as acetaldehyde (AA), and all are genotoxic in the same way. In addition, ethanol acts in the oral mucosa as a solvent and therefore increases the cellular membrane permeability to carcinogens. Carcinogens found in tobacco are also concentrated in marijuana, but the latter also contains high levels of cannabinoids, bioactive compounds responsible for several effects such as euphoria and analgesia. However, Δ(9)-tetrahydrocannabinol (Δ(9)-THC), the major psychotropic cannabinoid found in plants, causes a reduction of cellular metabolism and induction of apoptosis, both of which are anti-neoplastic properties. Apart from limited epidemiologic and experimental data, the effects of concomitant chronic exposure to marijuana (or Δ(9)-THC), tobacco and alcohol in OSCC development and progression is poorly known. This paper reviews the most recent findings on the effects of marijuana over cellular proliferation, as well as in the risk for OSCC, with emphasis on its interaction with tobacco and ethanol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinógenos/toxicidade , Carcinoma de Células Escamosas/etiologia , Fumar Maconha/efeitos adversos , Neoplasias Bucais/etiologia , Fumar/efeitos adversos , Bebidas Alcoólicas/toxicidade , Cannabis/toxicidade , Progressão da Doença , Relação Dose-Resposta a Droga , Etanol/toxicidade , Humanos , Fatores de Risco
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