Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.807
Filtrar
1.
Biol Pharm Bull ; 45(3): 339-353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35228400

RESUMO

Transforming growth factor (TGF)-ß1 and prostaglandin E2 (PGE2) are humoral factors critically involved in the induction of immunosuppression in the microenvironment of various types of tumors, including melanoma. In this study, we identified a natural compound that attenuated TGF-ß1- and PGE2-induced immunosuppression and examined its effect on B16 melanoma growth in mice. By screening 502 natural compounds for attenuating activity against TGF-ß1- or PGE2-induced suppression of cytolysis in poly(I:C)-stimulated murine splenocytes, we found that betulin was the most potent compound. Betulin also reduced TGF-ß1- and PGE2-induced downregulation of perforin and granzyme B mRNA expression and cell surface expression of NKG2D and CD69 in natural killer (NK) cells. Cell depletion and coculture experiments showed that NK cells, dendritic cells, B cells, and T cells were necessary for the attenuating effects of betulin. Structure-activity relationship analysis revealed that two hydroxyl groups at positions C3 and C28 of betulin, their cis-configuration, and methyl group at C30 played crucial roles in its attenuating activity. In a subcutaneous implantation model of B16 melanoma in mice, intratumor administration of betulin and LY2157299, a TGF-ß1 type I receptor kinase inhibitor, significantly retarded the growth of B16 melanoma. Notably, betulin increased significantly the number of CD69 positive NK cells in tumor sites at early stages of post-tumor cell injection. Our data suggest that betulin inhibits the growth of B16 melanoma by enhancing NK cell activity through attenuating the immunosuppressive tumor microenvironment.


Assuntos
Dinoprostona , Melanoma Experimental , Fator de Crescimento Transformador beta1 , Triterpenos , Animais , Dinoprostona/metabolismo , Células Matadoras Naturais , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Camundongos , Fator de Crescimento Transformador beta1/metabolismo , Triterpenos/farmacologia , Microambiente Tumoral
2.
Cells ; 11(4)2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35203350

RESUMO

Inter-organellar communication is emerging as one of the most crucial regulators of cellular physiology. One of the key regulators of inter-organellar communication is Mitofusin-2 (MFN2). MFN2 is also involved in mediating mitochondrial fusion-fission dynamics. Further, it facilitates mitochondrial crosstalk with the endoplasmic reticulum, lysosomes and melanosomes, which are lysosome-related organelles specialized in melanin synthesis within melanocytes. However, the role of MFN2 in regulating melanocyte-specific cellular function, i.e., melanogenesis, remains poorly understood. Here, using a B16 mouse melanoma cell line and primary human melanocytes, we report that MFN2 negatively regulates melanogenesis. Both the transient and stable knockdown of MFN2 leads to enhanced melanogenesis, which is associated with an increase in the number of mature (stage III and IV) melanosomes and the augmented expression of key melanogenic enzymes. Further, the ectopic expression of MFN2 in MFN2-silenced cells leads to the complete rescue of the phenotype at the cellular and molecular levels. Mechanistically, MFN2-silencing elevates mitochondrial reactive-oxygen-species (ROS) levels which in turn increases melanogenesis. ROS quenching with the antioxidant N-acetyl cysteine (NAC) reverses the MFN2-knockdown-mediated increase in melanogenesis. Moreover, MFN2 expression is significantly lower in the darkly pigmented primary human melanocytes in comparison to lightly pigmented melanocytes, highlighting a potential contribution of lower MFN2 levels to higher physiological pigmentation. Taken together, our work establishes MFN2 as a novel negative regulator of melanogenesis.


Assuntos
Melanoma Experimental , Melanossomas , Animais , Melaninas/metabolismo , Melanócitos/metabolismo , Melanoma Experimental/metabolismo , Melanossomas/metabolismo , Camundongos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Int J Mol Sci ; 23(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163074

RESUMO

The question of whether exosome lipids can be considered as potential cancer biomarkers faces our current limited knowledge of their composition. This is due to the difficulty in isolating pure exosomes, the variability of the biological sources from which they are extracted, and the uncertainty of the methods for lipid characterization. Here, we present a procedure to isolate exosomes and obtain a deep, repeatable, and rapid phospholipid (PL) composition of their lipid extracts, from embryonic murine fibroblasts (NIH-3T3 cell line) and none (B16-F1) and high (B16-F10) metastatic murine skin melanoma cells. The analytical method is based on High Performance Thin-Layer Chromatography with Ultraviolet and fluorescence densitometry and coupled to Electrospray (ESI)-tandem Mass Spectrometry (MS). Under the conditions described in this work, separation and determination of PL classes, (sphingomyelins, SM; phosphatidylcholines, PC; phosphatidylserines, PS; and phosphatidylethanolamines, PE) were achieved, expressed as µg PL/100 µg exosome protein, obtained by bicinchoninic acid assay (BCA). A detailed structural characterization of molecular species of each PL class was performed by simultaneous positive and negative ESI-MS and MS/MS directly from the chromatographic plate, thanks to an elution-based interface.


Assuntos
Cromatografia em Camada Delgada/métodos , Exossomos/metabolismo , Fibroblastos/metabolismo , Melanoma Experimental/patologia , Fosfolipídeos/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Melanoma Experimental/metabolismo , Camundongos , Células NIH 3T3 , Fosfolipídeos/análise
4.
Int J Mol Sci ; 23(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163092

RESUMO

2D culture as a model for drug testing often turns to be clinically futile. Therefore, 3D cultures (3Ds) show potential to better model responses to drugs observed in vivo. In preliminary studies, using melanoma (B16F10) and renal (RenCa) cancer, we confirmed that 3Ds better mimics the tumor microenvironment. Here, we evaluated how the proposed 3D mode of culture affects tumor cell susceptibility to anti-cancer drugs, which have distinct mechanisms of action (everolimus, doxorubicin, cisplatin). Melanoma spheroids showed higher resistance to all used drugs, as compared to 2D. In an RCC model, such modulation was only observed for doxorubicin treatment. As drug distribution was not affected by the 3D shape, we assessed the expression of MDR1 and mTor. Upregulation of MDR1 in RCC spheroids was observed, in contrast to melanoma. In both models, mTor expression was not affected by the 3D cultures. By NGS, 10 genes related with metabolism of xenobiotics by cytochrome p450 were deregulated in renal cancer spheroids; 9 of them were later confirmed in the melanoma model. The differences between 3D models and classical 2D cultures point to the potential to uncover new non-canonical mechanisms to explain drug resistance set by the tumor in its microenvironment.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Esferoides Celulares/efeitos dos fármacos , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Sobrevivência Celular , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Células Tumorais Cultivadas , Microambiente Tumoral
5.
Mol Med Rep ; 25(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35137924

RESUMO

The present study investigated the anti­melanogenic activity of 10 essential oils using the B16F10 cell model. Initially, a wide range of concentrations of these essential oils were screened in order to determine their toxicity levels. The assigned non­toxic concentrations of the tested essential oils were then used to evaluate their effects on melanogenesis. The effects of the essential oils with potent anti­melanogenic activity on cell proliferation, protection against H2O2­induced cell death and the expression of certain melanogenesis­related genes, including MITF, tyrosinase, tyrosinase related protein (TRP)­1 and TRP­2 were also evaluated. The results revealed that the essential oils extracted from Citrus unshiu, Juniperus chinensis L., Zanthoxylum piperitum and Artemisia capillaris (A. capillaris) inhibited melanogenesis. However, among these four extracts, only A. capillaris extract enhanced cell proliferation, exhibited anti­H2O2 activities and decreased the expression level of TRP­1. It was demonstrated that A. capillaris extract inhibited melanin synthesis via the downregulation of the TRP­1 translational level. These essential oil extracts, particularly that of A. capillaris, may thus be used as natural anti­melanogenic agents for therapeutic purposes and in the cosmetic industry for skin whitening effects with beneficial proliferative properties. However, further studies using in vivo models are required to validate these findings and to examine the effects of these extracts on various molecular pathways.


Assuntos
Artemisia/química , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Óleos Voláteis/farmacologia , Substâncias Protetoras/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citrus/química , Peróxido de Hidrogênio/toxicidade , Juniperus/química , Melaninas/genética , Melaninas/metabolismo , Glicoproteínas de Membrana/metabolismo , Camundongos , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Oxirredutases/metabolismo , Extratos Vegetais/farmacologia , Zanthoxylum/química
6.
Mar Drugs ; 20(2)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35200653

RESUMO

Melanin synthesis is a defense mechanism that prevents skin damage, but excessive accumulation of melanin occurs in the skin in various reactions such as pigmentation, lentigines, and freckles. Although anti-melanogenic effects have been demonstrated for various naturally occurring marine products that inhibit and control tyrosinase activity, most studies have not been extended to in vivo applications. Phlorofucofuroeckol-A (PFF-A, 12.5-100 µM) isolated from Ecklonia cava has previously been shown to have tyrosinase-mitigative effects in B16F10 cells, but it has not been evaluated in an in vivo model, and its underlying mechanism for anti-melanogenic effects has not been studied. In the present study, we evaluated the safety and efficacy of PFF-A for anti-melanogenic effects in an in vivo model. We selected low doses of PFF-A (1.5-15 nM) and investigated their mitigative effects on pigmentation stimulated by α-MSH in vivo and their related-mechanism in an in vitro model. The findings suggest that low-dose PFF-A derived from E. cava suppresses pigmentation in vivo and melanogenesis in vitro. Therefore, this study presents the possibility that PFF-A could be utilized as a new anti-melanogenic agent in the cosmeceutical industries.


Assuntos
Benzofuranos/farmacologia , Dioxinas/farmacologia , Melaninas/biossíntese , Feófitas/química , Pigmentação/efeitos dos fármacos , Animais , Benzofuranos/administração & dosagem , Benzofuranos/isolamento & purificação , Linhagem Celular Tumoral , Dioxinas/administração & dosagem , Dioxinas/isolamento & purificação , Relação Dose-Resposta a Droga , Feminino , Masculino , Melanoma Experimental/metabolismo , Camundongos , Peixe-Zebra , alfa-MSH/metabolismo
7.
Mar Drugs ; 20(2)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35200684

RESUMO

The tricyclic quinazoline alkaloid deoxyvasicinone (DOV, 1) was isolated from a marine-derived Streptomyces sp. CNQ-617, and its anti-melanogenic effects were investigated. Deoxyvasicinone was shown to decrease the melanin content of B16F10 and MNT-1 cells that have been stimulated by α-melanocyte-stimulating hormone (α-MSH). In addition, microscopic images of the cells showed that deoxyvasicinone attenuated melanocyte activation. Although, deoxyvasicinone did not directly inhibit tyrosinase (TYR) enzymatic activity, real-time PCR showed that it inhibited the mRNA expression of TYR, tyrosinase-related protein 1 (TRP-1), and tyrosinase-related protein 2 (TRP-2). In the artificial 3D pigmented skin model MelanodermTM, deoxyvasicinone brightened the skin significantly, as confirmed by histological examination. In conclusion, this study demonstrated that the marine microbial natural product deoxyvascinone has an anti-melanogenic effect through downregulation of melanogenic enzymes.


Assuntos
Melaninas/metabolismo , Quinazolinas/farmacologia , Pele/efeitos dos fármacos , Streptomyces/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanoma/metabolismo , Melanoma Experimental/metabolismo , Camundongos , Quinazolinas/isolamento & purificação , Pele/metabolismo
8.
Biochim Biophys Acta Mol Cell Res ; 1869(5): 119236, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35143901

RESUMO

Urea transporter B (UT-B, encoded by the SLC14A1 gene) is a membrane channel protein involved in urea transmembrane transport. Compared with normal tissues, UT-B expression is significantly decreased in most tumours, especially melanoma. However, the UT-B role in tumorigenesis and development is still unclear. Herein, we investigated the effects of UT-B overexpression on polyamine metabolism and the urea cycle in murine melanoma B16 cells, to explore the roles of mitochondrial dysfunction and p53 activation in cell growth and polyamines metabolism. UT-B overexpression in B16 cells decreased cell growth, increased apoptosis, and significantly altered metabolic pathways related to the urea cycle, which were characterized by reduced production of urea and polyamines and increased production of nitric oxide. Subsequently, we observed that activation of the p53 pathway may be the main cause of the above phenomena. The p53 inhibitor pifithrin-α partially restored the production of polyamines, but the mitochondrial morphology and function were still impaired. Further treatment of UT-B-overexpressing B16 cells with reactive oxygen species scavenging agent N-acetyl-l-cysteine and coenzyme Q10 restored cell viability and mitochondrial function and increased polyamine production. In conclusion, UT-B overexpression caused mitochondrial dysfunction and increased oxidative stress in B16 cells, and then activated p53 expression, which may be one of the mechanisms leading to the decrease in intracellular polyamines.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Poliaminas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acetilcisteína/farmacologia , Animais , Apoptose , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo/efeitos dos fármacos , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Putrescina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Tolueno/análogos & derivados , Tolueno/farmacologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia
9.
Bioengineered ; 13(2): 4557-4572, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35142593

RESUMO

Integrins play an important role in multiple stages of tumor progression and metastasis. Previous studies have shown synergistic effects of combined αvß6-integrin and αvß8-integrin inhibitors with immunotherapy. However, the role of αvß3-integrin inhibitor in tumor immunity is still unclear. In this study, we aimed to elucidate the impact of the αvß3-integrin inhibitor on PD-L1 expression and sensitivity to immune checkpoint blockade in melanoma. We investigated the effects of cilengitide, an αvß3-integrin inhibitor, on cell viability and apoptosis of melanoma cell lines. And we explored how cilengitide regulated the expression of PD-L1 in melanoma cells in vitro and in vivo, using immunofluorescence, flow cytometry, Western blotting, and immunohistochemistry. A subcutaneous B16 murine melanoma model was utilized to determine whether combining cilengitide with anti-PD1 therapy inhibited tumor growth and positively regulated tumor microenvironment (TME). Our results showed that cilengitide inhibited cell viability and induced apoptosis in B16 and A375 cell lines. Furthermore, cilengitide decreased PD-L1 expression by reducing STAT3 phosphorylation in two melanoma cell lines. Cilengitide also reduced subcutaneous tumor PD-L1 expression in the B16 murine melanoma model. Accordingly, cilengitide positively regulated antitumor immune responses and provided durable therapy when combined with anti-PD1 monoclonal antibody in the murine melanoma model. This combination therapy reduced tumor growth and extended survival. Our study highlights that cilengitide enhances the efficacy of anti-PD1 therapy and produces a stronger antitumor immune response. This combination therefore represents a novel therapeutic regimen that may improve immunotherapy treratment.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Integrina alfaVbeta3/antagonistas & inibidores , Melanoma Experimental/metabolismo , Neoplasias Cutâneas/metabolismo , Venenos de Serpentes/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL
10.
Mol Cell Biochem ; 477(4): 1041-1052, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34994923

RESUMO

Cytotoxic chemotherapy dominates the field of cancer treatment. Consequently, anticancer phytochemicals are largely screened on the basis of their cytotoxicity towards cancer cells which are achieved at higher doses, leading to various toxic side effects. Some phytochemicals also showed pro-carcinogenic effects at certain doses. The concept of hormesis has taught us to look into biphasic responses of phytochemicals in a more systematic way. Interestingly, the monoterpenoid alcohol, linalool, also has been reported to display both anti-oxidant and pro-oxidant properties, which prompted us to explore a probable biphasic effect on cancer cells. Cytotoxicity of various concentrations of linalool (0.1-4 mM) was tested on B16F10 murine melanoma cell line, and two sub-lethal concentrations (0.4 and 0.8 mM) were selected for further experiments. 0.4 mM linalool inhibited angiogenesis and metastasis, while 0.8 mM increased them. Similarly, B16F10 cell migration, invasion, and epithelial-mesenchymal transition markers also showed inhibition and induction with lower and higher linalool concentrations, respectively. Chorioallantoic membrane assay, scratch wound assay, and Boyden's chamber were used to analyze angiogenesis and metastasis. Expression of molecular markers such as vascular endothelial growth factor (VEGF) and its receptor phosphorylated VEGF receptor II (p-VEGFRII or p-Flk-1), Hypoxia-inducible factor-1 α (HIF-1α), E-cadherin, and vimentin were detected using Western blot, ELISA, PCR, qPCR, and immunofluorescence. Finally, ChIP assay was performed to evaluate HIF-1α association with VEGF promoter. Interestingly, measurement of intracellular reactive oxygen species at the selected concentrations of linalool using DCFDA in a flow cytometer showed that the phytochemical induced significant amount of ROS at 0.8 mM. This work sheds light on bimodal dose-response relationship exhibited by dietary phytochemicals like linalool, and it should be taken into consideration to elicit a desirable therapeutic effect.


Assuntos
Monoterpenos Acíclicos/farmacologia , Melanoma Experimental , Neovascularização Patológica , Animais , Embrião de Galinha , Células HEK293 , Humanos , Melanoma Experimental/sangue , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Metástase Neoplásica , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia
11.
J Ethnopharmacol ; 289: 115009, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35077827

RESUMO

ETHNO-PHARMACOLOGICAL RELEVANCE: The bark of Semialarium mexicanum commonly known as 'Cancerina' is used as an infusion in Central America and Mexico to treat various wound infections, as well as skin and vaginal ulcers. AIM OF THE STUDY: This study aimed to determine the wound healing, anti-inflammatory and anti-melanogenic activities of the aqueous extract of Semialarium mexicanum and to identify the compounds related to these activities. MATERIALS AND METHODS: A bio-guided isolation of the active compounds of Semialarium mexicanum was carried out, selecting the sub-extracts and fractions depending on their wound healing, anti-inflammatory and anti-melanogenic activities in the RAW 264.7, NIH/3T3 and B16-F10 cells. RESULTS: Three compounds were obtained and characterised by nuclear magnetic resonance and mass spectrometry. These compounds are (3ß)-3-Hydroxy-urs-12-en-28-oic acid (1), (3ß)-Urs-12-ene-3,28-diol (2) and (2α, 19α)-2,19-Dihydroxy-3-oxo-urs-12-en-28-oic acid (3). Regarding the anti-inflammatory activity, the three compounds inhibited the production of NF-κB and NO, however, compound 3 was the most active with IC50 values of 8.15-8.19 µM and 8.94-9.14 µM, respectively, in all cell lines. The anti-melanogenic activity of these compounds was evaluated by the inhibition of tyrosinase and melanin in the B16-F10 cell line. The three compounds showed anti-melanogenic activity, however, compound 3 was the most active with an IC50 of 8.03 µM for the inhibition of tyrosinase production, and an IC50 of 8.53 µM for the inhibition of melanin production. Finally, concerning the wound healing activity, the three compounds presented proliferative activity in all the tested cell lines, however, compound 3 showed higher cell proliferation percentages than compounds 1 and 2 (88.89-89.60% compared to 64.92-65.71% and 71.53-71.99%, respectively). CONCLUSION: The wound healing, anti-inflammatory and anti-melanogenic activity of the aqueous extract of Semialarium mexicanum was tested and analysed in the present study, after having isolated three ursane-type triterpenes.


Assuntos
Anti-Inflamatórios/farmacologia , Celastraceae/química , Triterpenos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular Tumoral , Concentração Inibidora 50 , Medicina Tradicional , Melaninas/metabolismo , Melanoma Experimental/metabolismo , Camundongos , Células NIH 3T3 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Triterpenos/química , Triterpenos/isolamento & purificação
12.
Molecules ; 27(1)2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35011507

RESUMO

Fungal mycelium cultures are an alternative to natural sources in order to obtain valuable research materials. They also enable constant control and adaptation of the process, thereby leading to increased biomass growth and accumulation of bioactive metabolites. The present study aims to assess the biosynthetic potential of mycelial cultures of six Ganoderma species: G. adspersum, G. applanatum, G. carnosum, G. lucidum, G. pfeifferi, and G. resinaceum. The presence of phenolic acids, amino acids, indole compounds, sterols, and kojic acid in biomass extracts was determined by HPLC. The antioxidant and cytotoxic activities of the extracts and their effects on the inhibition of selected enzymes (tyrosinase and acetylcholinesterase) were also evaluated. The total content of phenolic acids in the extracts ranged from 5.8 (G. carnosum) to 114.07 mg/100 g dry weight (d.w.) (G. pfeifferi). The total content of indole compounds in the extracts ranged from 3.03 (G. carnosum) to 11.56 mg/100 g d.w. (G. lucidum) and that of ergosterol ranged from 28.15 (G. applanatum) to 74.78 mg/100 g d.w. (G. adspersum). Kojic acid was found in the extracts of G. applanatum and G. lucidum. The tested extracts showed significant antioxidant activity. The results suggest that the analyzed mycelial cultures are promising candidates for the development of new dietary supplements or pharmaceutical preparations.


Assuntos
Antioxidantes/química , Inibidores da Colinesterase/química , Misturas Complexas/química , Citotoxinas/química , Ganoderma/química , Micélio/química , Animais , Antioxidantes/farmacologia , Inibidores da Colinesterase/farmacologia , Misturas Complexas/farmacologia , Citotoxinas/farmacologia , Ganoderma/crescimento & desenvolvimento , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Micélio/crescimento & desenvolvimento
13.
Mol Cell Biochem ; 477(1): 181-189, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34637074

RESUMO

The aim of the study was to investigate the in vitro and in vivo antitumor activity of leaves ethanol extract from Smilax fluminensis on murine melanoma. The extract was performed by ethylic alcohol and submitted to classical chemical analysis. Cytotoxicity test were performed on neoplastic cells, where antitumor activity was expressed in GI50 (concentration that inhibits 50% of cell growth) and the determination of selectivity index using a normal cell line. In addition, BALB/c mice models were used to evaluate the in vivo antitumor activity of extract in two different concentrations against B16-F10 melanoma cells. The tumor inhibition ratio was determined and the histopathological analyses of nodules and liver were compared. The chemical analysis indicated a major presence of phenolic compounds and flavonoids. Cytotoxicity test results that S. fluminensis extract was active in B16-F10 line (GI50: 4.37 µg/mL), being the extract considered a promising antineoplastic agent. In the experimental model, the inhibition percentage of tumoral growth was between 78.77 and 83.49%. Histopathology analysis of nodules showed necrotic cells reduction, adipocytes presence, melanin deposition, vascularization, and inflammatory process in a concentration-dependent manner. On the liver, the animals treated with the extract on both concentrations showed normal hepatic organization, normal hepatocytes, and absence of inflammatory focus. The results indicate that S. fluminensis extract demonstrated both in vitro and in vivo antitumor activity, reducing the tumoral growth in B16-F10 and could therefore be a promising antineoplastic agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Etanol/química , Melanoma Experimental/tratamento farmacológico , Extratos Vegetais/farmacologia , Smilax/química , Animais , Antineoplásicos Fitogênicos/química , Células HT29 , Humanos , Células MCF-7 , Melanoma Experimental/metabolismo , Camundongos , Células NIH 3T3 , Células PC-3 , Extratos Vegetais/química
14.
Cell Biol Int ; 46(1): 73-82, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34506671

RESUMO

Oxidative stress role on metformin process of dacarbazine (DTIC) inducing resistance of B16F10 melanoma murine cells are investigated. To induce resistance to DTIC, murine melanoma cells were exposed to increasing concentrations of dacarabazine (DTIC-res group). Metformin was administered before and during the induction of resistance to DTIC (MET-DTIC). The oxidative stress parameters of the DTIC-res group showed increased levels of malondialdehyde (MDA), thiol, and reduced nuclear p53, 8-hydroxy-2'-deoxyguanosine (8-OH-DG), nuclear factor kappa B (NF-ĸB), and Nrf2. In presence of metformin in the resistant induction process to DTIC, (MET-DTIC) cells had increased antioxidant thiols, MDA, nuclear p53, 8-OH-DG, Nrf2, and reducing NF-ĸB, weakening the DTIC-resistant phenotype. The exclusive administration of metformin (MET group) also induced the cellular resistance to DTIC. The MET group presented high levels of total thiols, MDA, and reduced percentage of nuclear p53. It also presented reduced nuclear 8-OH-DG, NF-ĸB, and Nrf2 when compared with the control. Oxidative stress and the studied biomarkers seem to be part of the alterations evidenced in DTIC-resistant B16F10 cells. In addition, metformin administration is able to play a dual role according to the experimental protocol, preventing or inducing a DTIC-resistant phenotype. These findings should help future research with the aim of investigating DTIC resistance in melanoma.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Antioxidantes/farmacologia , Dacarbazina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Metformina/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Animais , Linhagem Celular Tumoral , Malondialdeído/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/metabolismo
15.
Histochem Cell Biol ; 157(2): 153-172, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34837514

RESUMO

The incidence of cutaneous malignant melanoma is increasing worldwide. While the treatment of initial stages of the disease is simple, the advanced disease frequently remains fatal despite novel therapeutic options . This requires identification of novel therapeutic targets in melanoma. Similarly to other types of tumours, the cancer microenvironment plays a prominent role and determines the biological properties of melanoma. Importantly, melanoma cell-produced exosomes represent an important tool of intercellular communication within this cancer ecosystem. We have focused on potential differences in the activity of exosomes produced by melanoma cells towards melanoma-associated fibroblasts and normal dermal fibroblasts. Cancer-associated fibroblasts were activated by the melanoma cell-produced exosomes significantly more than their normal counterparts, as assessed by increased transcription of genes for inflammation-supporting cytokines and chemokines, namely IL-6 or IL-8. We have observed that the response is dependent on the duration of the stimulus via exosomes and also on the quantity of exosomes. Our study demonstrates that melanoma-produced exosomes significantly stimulate the tumour-promoting proinflammatory activity of cancer-associated fibroblasts. This may represent a potential new target of oncologic therapy .


Assuntos
Exossomos/metabolismo , Fibroblastos/metabolismo , Melanoma Experimental/metabolismo , Fibroblastos/patologia , Humanos , Melanoma Experimental/patologia , Células Tumorais Cultivadas
16.
Pharmacol Res ; 175: 105983, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34822972

RESUMO

Angiogenesis plays an important role in the growth and metastasis of solid tumors including melanoma. Inhibiting tumor-associated angiogenesis is a tactic in treating melanoma. Dioscin restrains angiogenesis in colon tumor and has anti-melanoma effects in cell and animal models. In a previous study, we found that dioscin inhibits Src/STAT3 signaling in melanoma cells. Activation of the Src/STAT3 pathway has been shown to promote tumor angiogenesis. This study aimed to determine whether dioscin's anti-melanoma effects is related to inhibiting Src/STAT3 signaling-mediated angiogenesis. In a B16F10 allograft mouse model, we found that dioscin inhibited melanoma growth and angiogenesis. To exclude the impact of tumor growth on angiogenesis, a chicken chorioallantoic membrane (CAM) model was used to verify the anti-angiogenic effect of dioscin. Results showed that dioscin suppressed vessel formation in CAM. To determine if tumor secreted pro-angiogenic cytokines are involved in the anti-angiogenic effect of dioscin, conditioned media from dioscin-treated A375 melanoma cells were used to culture human umbilical vein endothelial cells (HUVECs), and tube formation was monitored. It was observed that the tube formation of HUVECs was inhibited. Mechanistic studies revealed that dioscin inhibited the activation of Src and STAT3, and lowered mRNA and protein levels of STAT3 transcriptionally-regulated genes, in B16F10 melanomas. ELISA assays showed that dioscin decreased the secretion of MMP-2, MMP-9 and VEGF from A375 cells. Over-activation of STAT3 lessened the effects of dioscin in decreasing the secretion of pro-angiogenic cytokines from melanoma cells, and in inhibiting tube formation of HUVECs cultured with conditioned media from melanoma cell cultures. In summary, we for the first time demonstrated that inhibiting Src/STAT3 signaling-mediated angiogenesis is involved in the anti-melanoma effects of dioscin. This study provides further pharmacological groundwork for developing dioscin as an anti-melanoma agent.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Diosgenina/análogos & derivados , Melanoma Experimental/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fator de Transcrição STAT3/antagonistas & inibidores , Quinases da Família src/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Animais , Linhagem Celular Tumoral , Diosgenina/farmacologia , Diosgenina/uso terapêutico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fator de Transcrição STAT3/metabolismo , Carga Tumoral/efeitos dos fármacos , Quinases da Família src/metabolismo
17.
Am J Pathol ; 192(2): 379-388, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34861214

RESUMO

Vascular endothelial growth factor (VEGF) blockers are used widely in clinics to target various types of human cancer. Although VEGF blockers exert marked tumor suppressive effects, the therapeutic effects can be limited. Moreover, accumulating evidence shows that VEGF acts not just on endothelial cells but also on various nonendothelial cells, including tumor and immune cells, suggesting a need to revisit the bona fide action of VEGF on endothelial cells using specific genetic mouse models. Herein, tamoxifen-inducible endothelial-specific knockout mice lacking VEGF receptor 2 (Vegfr2), the major signal transducer for VEGF, were used. The initial event resulting from cessation of endothelial Vegfr2 signaling was vascular truncation and fragmentation, rather than maturation of abnormalized vessels. Although deletion of endothelial Vegfr2 suppressed intratumor hemorrhage, it enhanced hypoxia in tumor cells and reduced the number of infiltrating cytotoxic T cells, suggesting a profound reduction in intratumor blood flow. In various tissues, deletion of endothelial Vegfr2 induced regression of healthy capillaries in intestinal villi, substantiating intestinal perforation, which is one of the most common adverse effects of VEGF blockade in humans. Overall, the data suggest that some of the known effects of VEGF blockers on tumor vessels are caused by partial cessation of VEGF signaling, or by actions on nonendothelial cells. The results increase the understanding of the mechanisms underlying anti-angiogenic therapy.


Assuntos
Células Endoteliais , Deleção de Genes , Melanoma Experimental , Proteínas de Neoplasias , Neovascularização Patológica , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Animais , Hipóxia Celular/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
18.
J Nutr Biochem ; 100: 108910, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34801689

RESUMO

Isoflavone is a species of polyphenol found mainly in soy and soy products. Many studies have demonstrated its estrogen receptor (ER)-dependent action. Equol is an intestinal metabolite of a major soy isoflavone daidzein. We aimed to elucidate the mechanism for ER-independent actions of equol. Equol has been shown to inhibit proliferation of HeLa human cervical cancer cells and mouse melanoma B16 cells in an ER-independent manner. Using functional genetic screening, PAP associated domain containing 5 (PAPD5), which is a non-canonical poly(A) polymerase, was identified as an essential molecule in the ER-independent action. While peroral administration of equol inhibited tumor growth of control B16 cells subcutaneously inoculated in mice, it had little effect on the growth of PAPD5-ablated B16 cells. Intriguingly, equol progressed tumor growth of the PAPD5-ablated human breast cancer MCF-7 cells, which have high ERα expression. Equol has been found to induce polyadenylation of snoRNAs in a PAPD5-depdendent manner. Furthermore, peroral equol administration increased microRNA miR-320a expression in tumors. Together, these results suggest that equol may have a dual effect on ER-positive cancer cells, acting with, antiproliferative activity through PAPD5 and exhibiting proliferative activity via ERα and the former could be associated with miR-320a.


Assuntos
Proliferação de Células/efeitos dos fármacos , Equol/farmacologia , Melanoma Experimental/patologia , RNA Nucleotidiltransferases/metabolismo , Receptores de Estrogênio/metabolismo , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/metabolismo , Células HeLa , Humanos , Isoflavonas/farmacologia , Células MCF-7 , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Transplante de Neoplasias , RNA Nucleolar Pequeno/metabolismo
19.
In Vivo ; 36(2): 713-722, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35241526

RESUMO

BACKGROUND/AIM: Natural skin whiteners have been investigated for centuries. The development of preparations that safely achieve whitening of hyper-pigmented skin lesions is a challenge for the cosmetics industry. Furthermore, promoting rapid wound healing and minimizing inflammation in injured skin are key to prevent from abnormal pigmentation in scar tissue. Natural products, including the fungus Tremella fuciformis (TF), are attracting attention as potential sources of lead compounds for these applications. MATERIALS AND METHODS: We investigated the in vitro effects of TF on melanogenesis in murine B16F10 cells. Melanin and tyrosinase levels were measured after treatment with TF. Wound healing in human keratinocytes (HaCaT) and fibroblasts (Detroit 551) was also determined via cell migration assay prior to TF exposure. RESULTS: TF significantly decreased melanin content and tyrosinase expression in a concentration-dependent manner in B16F10 cells. Furthermore, TF promoted wound healing in human HaCaT keratinocytes and Detroit 551 fibroblasts. CONCLUSION: TF proved effectively on inhibiting melanogenesis and promoting wound healing in vitro, demonstrating its potential as a novel skin-whitening agent. However, further clinical studies of safety and efficacy are required.


Assuntos
Basidiomycota , Melanoma Experimental , Animais , Basidiomycota/metabolismo , Linhagem Celular Tumoral , Fibroblastos/metabolismo , Humanos , Queratinócitos/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , alfa-MSH/metabolismo , alfa-MSH/farmacologia
20.
Biochem Pharmacol ; 197: 114894, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34968486

RESUMO

Mithramycin A (MIT) has reacquired extensive research attention due to its anti-solid tumor activity and improved pharmacological production. Mechanismly, MIT was broadly used as a c-Myc inhibitor, and c-Myc regulated CD47 and PD-L1 expression which has been demonstrated. However, how MIT affects immune check-point molecules remains unknown. In this study, we found CD47 expression was higher in melanoma of pan-tissue array. MIT inhibited CD47 expression both in mRNA and protein level in melanoma cells (SK-MEL-28 and B16). MIT inhibited c-Myc, Sp-1 and CD47 expression in a concentration-dependent way. MIT inhibited the surface CD47 expression and promoted the phagocytosis of SK-MEL-28 cells by THP-1 cells. We found MIT inhibited tumor growth in melanoma allograft mice and CD47 expression in tumor mass. We also found MIT upregulated PD-L1 expression in cancer cells possibly via inhibiting PD-L1 ubiquitination, increasing ROS and IFN-γ. Combination of MIT and anti-PD-1 antibody showed enhanced antitumor activity compared to MIT and anti-PD-1 antibody alone in MC38 allograft mice. Using immune checkpoint array we found MIT inhibited expression of FasL and Galectin3. These results suggest that MIT inhibits CD47 expression, while improves PD-L1 expression. Furthermore, the combination of MIT and anti-PD-1 antibody exerts potent antitumor effect.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Antígeno B7-H1/biossíntese , Antígeno CD47/biossíntese , Melanoma Experimental/metabolismo , Plicamicina/uso terapêutico , Animais , Antibióticos Antineoplásicos/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno CD47/antagonistas & inibidores , Relação Dose-Resposta a Droga , Feminino , Expressão Gênica , Humanos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Plicamicina/farmacologia , Células THP-1 , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...