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1.
Nat Immunol ; 22(11): 1403-1415, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34686867

RESUMO

Tumor-associated macrophages (TAMs) display pro-tumorigenic phenotypes for supporting tumor progression in response to microenvironmental cues imposed by tumor and stromal cells. However, the underlying mechanisms by which tumor cells instruct TAM behavior remain elusive. Here, we uncover that tumor-cell-derived glucosylceramide stimulated unconventional endoplasmic reticulum (ER) stress responses by inducing reshuffling of lipid composition and saturation on the ER membrane in macrophages, which induced IRE1-mediated spliced XBP1 production and STAT3 activation. The cooperation of spliced XBP1 and STAT3 reinforced the pro-tumorigenic phenotype and expression of immunosuppressive genes. Ablation of XBP1 expression with genetic manipulation or ameliorating ER stress responses by facilitating LPCAT3-mediated incorporation of unsaturated lipids to the phosphatidylcholine hampered pro-tumorigenic phenotype and survival in TAMs. Together, we uncover the unexpected roles of tumor-cell-produced lipids that simultaneously orchestrate macrophage polarization and survival in tumors via induction of ER stress responses and reveal therapeutic targets for sustaining host antitumor immunity.


Assuntos
Estresse do Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Ativação de Macrófagos , Melanoma/metabolismo , Lipídeos de Membrana/metabolismo , Neoplasias Cutâneas/metabolismo , Macrófagos Associados a Tumor/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Retículo Endoplasmático/ultraestrutura , Glucosilceramidase/metabolismo , Membranas Intracelulares/ultraestrutura , Melanoma/genética , Melanoma/ultraestrutura , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/ultraestrutura , Evasão Tumoral , Microambiente Tumoral , Macrófagos Associados a Tumor/ultraestrutura , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismo
2.
Cells ; 10(4)2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917849

RESUMO

It was reported that lumican inhibits the activity of metalloproteinase MMP-14 and melanoma cell migration in vitro and in vivo. Moreover, Snail triggers epithelial-to-mesenchymal transition and the metastatic potential of cancer cells. Therefore, the aim of this study was to examine the effect of lumican on Mock and Snail overexpressing melanoma B16F1 cells in vivo. Lung metastasis was analyzed after intravenous injections of Mock-B16F1 and Snail-B16F1 cells in Lum+/+ and Lum-/- mice. At day 14, mice were sacrificed, and lungs were collected. The number of lung metastatic nodules was significantly higher in mice injected with Snail-B16F1 cells as compared to mice injected with Mock-B16F1 cells confirming the pro-metastatic effect of Snail. This effect was stronger in Lum-/- mice as compared to Lum+/+, suggesting that endogenous lumican of wild-type mice significantly inhibits metastasis to lungs. Scanning electron and confocal microscopy investigations demonstrated that lumican inhibits the development of elongated cancer cell phenotypes which are known to develop invadopodia releasing MMPs. Moreover, lumican was shown to affect the expression of cyclin D1, cortactin, vinculin, hyaluronan synthase 2, heparanase, MMP-14 and the phosphorylation of FAK, AKT, p130 Cas and GSK3α/ß. Altogether, these data demonstrated that lumican significantly inhibits lung metastasis in vivo, as well as cell invasion in vitro, suggesting that a lumican-based strategy targeting Snail-induced metastasis could be useful for melanoma treatment.


Assuntos
Biomarcadores Tumorais/metabolismo , Lumicana/metabolismo , Melanoma/patologia , Podossomos/patologia , Neoplasias Cutâneas/patologia , Animais , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Forma Celular , Cortactina/metabolismo , Ciclina D1/metabolismo , Matriz Extracelular/metabolismo , Adesões Focais/metabolismo , Humanos , Ácido Hialurônico/metabolismo , Neoplasias Pulmonares/secundário , Melanoma/metabolismo , Melanoma/ultraestrutura , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Fosforilação , Transdução de Sinais , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/ultraestrutura , Fatores de Transcrição da Família Snail/metabolismo , Vinculina/metabolismo
3.
J Cutan Pathol ; 48(9): 1115-1123, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33660310

RESUMO

BACKGROUND: PRAME (PReferentially expressed Antigen in Melanoma) immunohistochemistry has demonstrated high specificity for unequivocal melanomas; however, its utility in ambiguous melanocytic neoplasms has yet to be fully elucidated. METHODS: Cases of challenging melanocytic neoplasms were subclassified into one of three categories: challenging, favor benign (FB), challenging, cannot be subclassified (CCS), or challenging, favor malignant (FM). Using a previously published system, whereby cases with diffuse staining (>75%) were considered positive, scoring of PRAME was performed. Additionally, tumors with hotspot staining were also considered positive. RESULTS: Sixteen out of 85 tumors showed positive staining representing 5% of FB tumors, 24% of CCS tumors, and 47% of FM. In FB and CCS tumors, positive staining was mainly encountered in atypical intraepidermal melanocytic proliferations and spitzoid neoplasms. The specificity of positive PRAME staining was 95% and its concordance with the final diagnostic interpretation was 75%. CONCLUSIONS: PRAME positivity is more common in neoplasms favored to be malignant by histopathologic evaluation. Its clinical utility may include early diagnosis of incipient melanoma in situ. Rarely, benign melanocytic neoplasms could show diffuse expression of PRAME, and additional studies are needed to determine optimal utilization. Lastly, hotspot staining may increase its sensitivity without much compromise in specificity.


Assuntos
Antígenos de Neoplasias/metabolismo , Imuno-Histoquímica/métodos , Melanócitos/patologia , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Masculino , Melanoma/classificação , Melanoma/diagnóstico , Melanoma/ultraestrutura , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Sensibilidade e Especificidade , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/ultraestrutura , Adulto Jovem , Melanoma Maligno Cutâneo
5.
Anticancer Res ; 40(6): 3505-3512, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32487651

RESUMO

AIM: To assess the prognostic significance of nucleolar morphological parameters in a large cohort of patients with uveal melanoma. PATIENTS AND METHODS: The presence, size and number of nucleoli of cancer cells were assessed in haematoxylin and eosin (HE)-stained slides of 164 formalin-fixed paraffin-embedded primary uveal melanoma tissue specimens. The results were correlated with clinicopathological features and patient survival. RESULTS: The presence of macronucleoli and multiple nucleoli significantly correlated with the epithelioid type of uveal melanoma, high mitotic rate, and marked pleomorphism. There was a positive correlation between the presence of macronucleoli as well as the number of nucleoli and the largest tumour basal diameter. The increased nucleolus count in tumour cells positively correlated with primary tumour (pT) staging. The presence of both prominent and multiple nucleoli was associated with significantly reduced overall and disease-free survival. CONCLUSION: Histological assessment of nucleolar morphology in routine HE staining would be a helpful low-cost method to obtain reliable prognostic information.


Assuntos
Nucléolo Celular/patologia , Melanoma/patologia , Neoplasias Uveais/patologia , Idoso , Nucléolo Celular/ultraestrutura , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Melanoma/ultraestrutura , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Carga Tumoral , Neoplasias Uveais/mortalidade , Neoplasias Uveais/ultraestrutura
6.
Cells ; 9(5)2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414111

RESUMO

Metastatic melanoma is the most aggressive type of skin cancer. Previously, we identified the plasma membrane Ca2+ pump isoform 4b (PMCA4b or ATP2B4) as a putative metastasis suppressor in BRAF mutant melanoma cells. Metastasis suppressors are often downregulated in cancer, therefore, it is important to identify the pathways involved in their degradation. Here, we studied the role of p38 MAPK in PMCA4b degradation and its effect on melanoma metastasis. We found that activation of p38 MAPK induces internalization and subsequent degradation of PMCA4b through the endo/lysosomal system that contributes to the low PMCA4b steady-state protein level of BRAF mutant melanoma cells. Moreover, BRAF wild type cell models including a doxycycline-inducible HEK cell system revealed that p38 MAPK is a universal modulator of PMCA4b endocytosis. Inhibition of the p38 MAPK pathway markedly reduced migration, colony formation and metastatic activity of BRAF mutant cells in vitro partially through an increase in PMCA4b and a decrease in ß4 integrin abundance. In conclusion, our data suggest that the p38 MAPK pathway plays a key role in PMCA4b degradation and inhibition of this pathway-by increasing the stability of PMCA4b-may provide a potential therapeutic target for inhibition of melanoma progression and metastasis.


Assuntos
Movimento Celular/genética , Melanoma/genética , Melanoma/patologia , Mutação/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Proteólise , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Cálcio/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Melanoma/enzimologia , Melanoma/ultraestrutura , NF-kappa B/metabolismo , Metástase Neoplásica , Inibidores de Proteínas Quinases/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/ultraestrutura , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Ensaio Tumoral de Célula-Tronco , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
7.
Nat Commun ; 11(1): 1335, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32165639

RESUMO

Immune checkpoint blockade (ICB)-based or natural cancer immune responses largely eliminate tumours. Yet, they require additional mechanisms to arrest those cancer cells that are not rejected. Cytokine-induced senescence (CIS) can stably arrest cancer cells, suggesting that interferon-dependent induction of senescence-inducing cell cycle regulators is needed to control those cancer cells that escape from killing. Here we report in two different cancers sensitive to T cell-mediated rejection, that deletion of the senescence-inducing cell cycle regulators p16Ink4a/p19Arf (Cdkn2a) or p21Cip1 (Cdkn1a) in the tumour cells abrogates both the natural and the ICB-induced cancer immune control. Also in humans, melanoma metastases that progressed rapidly during ICB have losses of senescence-inducing genes and amplifications of senescence inhibitors. Metastatic cells also resist CIS. Such genetic and functional alterations are infrequent in metastatic melanomas regressing during ICB. Thus, activation of tumour-intrinsic, senescence-inducing cell cycle regulators is required to stably arrest cancer cells that escape from eradication.


Assuntos
Ciclo Celular , Senescência Celular , Interferons/metabolismo , Melanoma/imunologia , Melanoma/patologia , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , Imunoterapia , Antígeno Ki-67/metabolismo , Linfonodos/patologia , Melanoma/terapia , Melanoma/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT1/metabolismo , Análise de Sobrevida , Carga Tumoral
8.
Cells ; 9(2)2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012858

RESUMO

Urokinase Plasminogen Activator (uPA) Receptor (uPAR) is a well-known GPI-anchored three-domain membrane protein with pro-tumor roles largely shown in all the malignant tumors where it is over-expressed. Here we have exploited the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 gene knock out approach to investigate its role in the oxidative metabolism in human melanoma and colon cancer as the consequences of its irreversible loss. Knocking out PLAUR, a uPAR-encoding gene, in A375p, A375M6 and HCT116, which are two human melanoma and a colon carcinoma, respectively, we have observed an increased number of mitochondria in the two melanoma cell lines, while we evidenced an immature biogenesis of mitochondria in the colon carcinoma culture. Such biological diversity is, however, reflected in a significant enhancement of the mitochondrial spare respiratory capacity, fueled by an increased expression of GLS2, and in a decreased glycolysis paired with an increased secretion of lactate by all uPAR KO cells. We speculated that this discrepancy might be explained by an impaired ratio between LDHA and LDHB.


Assuntos
Neoplasias do Colo/metabolismo , Técnicas de Inativação de Genes , Glicólise , Melanoma/metabolismo , Fosforilação Oxidativa , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Sequência de Bases , Proteína 9 Associada à CRISPR/metabolismo , Linhagem Celular Tumoral , Respiração Celular/genética , Neoplasias do Colo/genética , Neoplasias do Colo/ultraestrutura , Desoxirribonuclease I/metabolismo , Fluorescência , Regulação Neoplásica da Expressão Gênica , Glicólise/genética , Humanos , Ácido Láctico/metabolismo , Melanoma/genética , Melanoma/ultraestrutura , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Biogênese de Organelas , RNA Guia de Cinetoplastídeos/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Estresse Fisiológico
9.
J Cutan Pathol ; 47(6): 541-547, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31943331

RESUMO

Undifferentiated melanoma should be considered in the differential diagnosis of sarcomatoid cutaneous malignancies to ensure that patients receive the correct treatment. Dermatopathologists should recognize the pitfalls of relying too heavily on immunohistochemistry to establish this diagnosis and consider ancillary tests, including single-nucleotide polymorphism (SNP) copy number arrays and targeted next-generation sequencing (NGS), when a definitive diagnosis cannot be rendered on a primary or metastatic tumor. This technology can also help to exclude a collision of melanoma and sarcoma when both differentiated and undifferentiated components are juxtaposed. We describe an exceedingly rare, illustrative example of undifferentiated sarcomatoid melanoma presenting as a pedunculated nodule. The clinical context and presence of a small differentiated component helped to establish the diagnosis; however, the transition from differentiated to undifferentiated melanoma was accompanied by an abrupt loss of S100, Sox10, MITF, MelanA, and HMB45 with gain of CD10 and p63 staining. SNP copy number array and NGS revealed shared chromosomal copy number changes and overlapping mutations with additional aberrances detected exclusively in the sarcomatoid component, thereby excluding a collision tumor and confirming our putative impression of melanoma with progression to an undifferentiated sarcomatoid phenotype.


Assuntos
Melanoma/genética , Proteínas de Membrana/metabolismo , Neprilisina/metabolismo , Sarcoma/genética , Assistência ao Convalescente , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Diagnóstico Diferencial , Humanos , Linfadenopatia/patologia , Antígeno MART-1/metabolismo , Masculino , Melanoma/patologia , Melanoma/ultraestrutura , Antígenos Específicos de Melanoma/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Mutação , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição SOXE/metabolismo , Sarcoma/patologia , Sarcoma/secundário , Neoplasias Cutâneas/patologia , Neoplasias de Tecidos Moles/patologia , Resultado do Tratamento , Antígeno gp100 de Melanoma
10.
Bull Exp Biol Med ; 168(2): 285-290, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31782005

RESUMO

Typical blood capillaries and vessels in uveal melanoma were shown and different types of uveal melanoma stromal cells were determined by electron microscopy and immunohistochemical analysis. Macrophages, fibroblasts of varying degrees of differentiation and endothelial-like cells with numerous caveolae in the cytoplasm were found in the channels of the extracellular matrix surrounding accumulations of tumor cells. The presence local structures positively stained for markers of the blood and lymphatic vessels (CD31 and podoplanin) in channels of the extracellular matrix suggests that the described endothelial-like cells can be the structural basis for blood and lymphatic vessels of the tumor.


Assuntos
Células Endoteliais/citologia , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Macrófagos/citologia , Melanoma/ultraestrutura , Células Estromais/ultraestrutura , Neoplasias Uveais/ultraestrutura , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Diferenciação Celular/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Vasos Linfáticos/citologia , Melanoma/patologia , Microscopia Eletrônica , Pessoa de Meia-Idade , Úvea/irrigação sanguínea , Úvea/citologia , Úvea/patologia , Neoplasias Uveais/patologia
11.
Mol Vis ; 25: 502-516, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31588174

RESUMO

Purpose: Periodic acid-Schiff (PAS) positive patterns of vasculogenic mimicry (VM) have been associated with poor prognosis in uveal melanoma (UM). We examined these patterns with digital image analysis and transmission electron microscopy, and correlated them with BAP-1 expression, gene expression class, macrophage infiltration, and metastatic disease in full tumor cross-sections and intratumor regions. Methods: Thirty-two enucleated eyes with UM were stained immunohistochemically (BAP-1, laminin, CD31, and CD68) and with PAS without hematoxylin counterstain. Retrospective data on gene expression class and patient survival were retrieved. Tumor sections were digitally scanned and analyzed with the QuPath Bioimage analysis software, and imaged with transmission electron microscopy. Results: The mean area proportion covered by CD31, laminin, and PAS positive patterns in tumor cross-sections was 0.9% (SD 0.6), 3.0% (SD 1.9), and 8.4% (SD 5.9), respectively. PAS density was statistically significantly greater in tumors with gene expression class 2 (p=0.02). The cumulative 5-year metastasis-free survival decreased for each quartile of increased PAS density (1.0, 0.75, 0.40, and 0.17, p=0.004). Forty percent of the tumors had heterogeneous BAP-1 expression. Intratumor regions with low BAP-1 expression were more likely to harbor VM (p<0.0001), and had statistically significantly greater PAS density (p<0.0001) and number of CD68 positive cells (p=0.01). Conclusions: PAS positive patterns in UM are composed of a mixture of blood vessels and extracellular matrix (ECM), including VM. Increased density of PAS positive patterns correlated with gene expression class and metastasis, and colocated to tumor regions with macrophage infiltration and low BAP-1 expression.


Assuntos
Regulação Neoplásica da Expressão Gênica , Macrófagos/patologia , Melanoma/irrigação sanguínea , Melanoma/genética , Neovascularização Patológica/genética , Reação do Ácido Periódico de Schiff , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Neoplasias Uveais/irrigação sanguínea , Neoplasias Uveais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Corioide/irrigação sanguínea , Corioide/patologia , Corioide/ultraestrutura , Intervalo Livre de Doença , Enucleação Ocular , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Macrófagos/metabolismo , Masculino , Melanoma/patologia , Melanoma/ultraestrutura , Pessoa de Meia-Idade , Metástase Neoplásica , Neovascularização Patológica/patologia , Reconhecimento Automatizado de Padrão , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/metabolismo , Neoplasias Uveais/patologia , Neoplasias Uveais/ultraestrutura , Adulto Jovem
12.
J Biochem Mol Toxicol ; 33(9): e22376, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31328346

RESUMO

Nickel oxide nanoparticles (NiO-NPs) are progressively used for an immense number of new applications in modern industries sectors. Nevertheless, the toxic impact of NiO-NPs has not been clearly elucidated on human melanoma cell lines at the cellular and molecular level. Hence, this study was designed to examine the in vitro cytotoxicity potentials of NiO-NPs on malignant cutaneous melanoma (MCM) mitochondria. Results revealed that NiO-NPs significantly increased reactive oxygen species level, lipid peroxidation, and mitochondrial membrane potential and decreased succinate dehydrogenase activity, glutathione level, and ATP content on skin mitochondria isolated from the mouse model of melanoma compared with the non-cancerous mouse skin mitochondria. Our results revealed that NiO-NPs induced lysosomal membrane labialization on mentioned mitochondria. The current study showed that NiO-NPs could significantly induce selective cytotoxicity on MCM mitochondria. Therefore, this compound may be considered as a promising candidate for further in vivo and clinical studies to reach a new anti-MCM drug.


Assuntos
Lisossomos/efeitos dos fármacos , Melanoma/patologia , Nanopartículas Metálicas/toxicidade , Mitocôndrias/efeitos dos fármacos , Níquel/química , Pele/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Lisossomos/metabolismo , Masculino , Melanoma/metabolismo , Melanoma/ultraestrutura , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
13.
Actas dermo-sifiliogr. (Ed. impr.) ; 110(5): 366-371, jun. 2019. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-180925

RESUMO

Antecedentes: Las queratosis seborreicas (QS) son reconocidas con facilidad a través de una aproximación clínica y dermatoscópica, sin embargo, algunas lesiones presentan un comportamiento que simula distintas afecciones de la piel que carecen de criterios clínicos y dermatoscópicos típicos. Objetivo: El objetivo de este estudio fue encontrar características dermatoscópicas específicas o un patrón general que permita mejorar las habilidades diagnósticas en los casos de QS complejas. Materiales y métodos: Estudiamos 72 casos de QS atípicas extirpadas entre septiembre del 2014 y septiembre del 2017 utilizando para ello el algoritmo en 2 pasos modificado por Malvehy (2002) y Argenziano (2003). Resultados: En nuestra población de estudio, encontramos una media de 4,04 de los 15 criterios específicos dermatoscópicos de QS (por ejemplo, múltiples puntos similares a quistes tipo milium). Se identificaron los siguientes criterios adicionales no incluidos en el algoritmo en 2 pasos: velo azul-blanquecino (en 3 QS; 4,2%), patrón vascular polimorfo (18 QS; 25%), manchas/glóbulos (6 QS; 8,3%), manchas blancas brillantes (3 lesiones; 4,2%). Los patrones generales más representados fueron el patrón reticular (27 QS; 37,5%) y no específico (15 QS; 20,8%). Todas las lesiones exhibieron hallazgos peculiares de QS; además, en el 79,2% de todas las lesiones estudiadas se identificaron elementos indicativos de lesión melanocítica. Cuando comparamos la literatura con nuestros resultados, encontramos 3 diferencias significativas: a) una menor prevalencia de los criterios específicos de QS en nuestra población de estudio; b) la identificación de hallazgos generalmente no relacionados con la QS, como el velo azul-blanquecino, el patrón vascular polimorfo, las manchas/glóbulos y las manchas blancas brillantes, y c) también se describieron 2 patrones no definidos previamente representados por «patrón no específico» (20,9% de todas las lesiones examinadas) y "patrón vascular" (12,5% de todas las lesiones examinadas). No se encontró ninguna característica específica o patrón general estadísticamente significativo para el diagnóstico dermatoscópico de QS de diagnóstico difícil. Conclusión: A pesar de los hallazgos, no hemos encontrado ningún patrón específico o general estadísticamente significativo para el diagnóstico dermatoscópico de la QS de diagnóstico difícil. Conforme al algoritmo en 2 pasos y el sistema de puntuación dermatoscópica para lesiones melanocíticas y no melanocíticas, las QS con uno o varios hallazgos dermatoscópicos típicos de lesión melanocítica deberían ser extirpados quirúrgicamente para excluir el melanoma clásico o el melanoma que simula una QS


Background: Seborrheic keratoses (SK) are easily recognizable by clinical and dermoscopic approach, nevertheless, some lesions act as a simulator of different skin conditions lacking typical clinical and dermoscopic criteria. Objective: The aim of our study was to find specific dermoscopic features or a global pattern to improve diagnostic skills for challenging SK. Materials and methods: We examined 72 atypical SK excised from September 2014 up to September 2017 by using the 2-step algorithm modified by Malvehy (2002) and Argenziano (2003). Results: In our study population, an average of 4.04 out of 15 dermoscopic specific criteria for SK was found (for example, multiple milia-like cysts). Additional criteria not included in 2-step algorithm were blue-whitish veil (found in 3 SK; 4.2%), polymorphous vessels (18 SK; 25%), blotch/globules (6 SK; 8.3%), shiny white streaks (3 lesions; 4.2%). The most represented global patterns were reticular (27 SK; 37.5%) and not specific (15 SK; 20.8%). All lesions exhibited peculiar findings of SK, furthermore elements suggestive for melanocytic lesion were found in 79.2% of all lesions. Comparing the literature and our results, we found 3 significant differences: a) the less prevalence of SK specific criteria in our study population; b) the description of findings usually not related to SK, among which blue-whitish veil, polymorphous vessels, blotch/globules and shiny white streaks, and c) 2 patterns not previously defined represented by "not specific pattern" (20.9% of all lesions examined) and "vascular pattern" (12.5% of all lesions examined) were also described. No specific feature or global pattern, statistically significant for dermoscopic diagnosis of difficult-to-diagnose SK have been found. Conclusion. Nevertheless the useful findings, no specific feature or global pattern statistically significant for dermoscopic diagnosis of challenging SK have been found. According to the 2-step algorithm and the dermatoscopic scoring system for melanocytic and not melanocytic lesion, SK with one or more dermatoscopic findings typical of melanocytic lesion should be removed surgically to exclude classic melanoma or melanoma mimicking SK


Assuntos
Humanos , Ceratose Seborreica/diagnóstico por imagem , Técnicas e Procedimentos Diagnósticos/instrumentação , Neoplasias Cutâneas , Melanoma/diagnóstico por imagem , Diagnóstico Diferencial , Técnicas e Procedimentos Diagnósticos , Melanoma/ultraestrutura
14.
Int J Nanomedicine ; 14: 3155-3176, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118629

RESUMO

BACKGROUND: Traditional physicochemical approaches for the synthesis of compounds, drugs, and nanostructures developed as potential solutions for antimicrobial resistance or against cancer treatment are, for the most part, facile and straightforward. Nevertheless, these approaches have several limitations, such as the use of toxic chemicals and production of toxic by-products with limited biocompatibility. Therefore, new methods are needed to address these limitations, and green chemistry offers a suitable and novel answer, with the safe and environmentally friendly design, manufacturing, and use of minimally toxic chemicals. Green chemistry approaches are especially useful for the generation of metallic nanoparticles or nanometric structures that can effectively and efficiently address health care concerns. OBJECTIVE: Here, tellurium (Te) nanowires were synthesized using a novel green chemistry approach, and their structures and cytocompatibility were evaluated. METHOD: An easy and straightforward hydrothermal method was employed, and the Te nanowires were characterized using transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, and optical microscopy for morphology, size, and chemistry. Cytotoxicity tests were performed with human dermal fibroblasts and human melanoma cells (to assess anticancer properties). The results showed that a treatment with Te nanowires at concentrations between 5 and 100 µg/mL improved the proliferation of healthy cells and decreased cancerous cell growth over a 5-day period. Most importantly, the green chemistry -synthesized Te nanowires outperformed those produced by traditional synthetic chemical methods. CONCLUSION: This study suggests that green chemistry approaches for producing Te nanostructures may not only reduce adverse environmental effects resulting from traditional synthetic chemistry methods, but also be more effective in numerous health care applications.


Assuntos
Antineoplásicos/farmacologia , Química Verde/métodos , Nanopartículas Metálicas/química , Nanofios/química , Telúrio/química , Morte Celular , Linhagem Celular Tumoral , Fibroblastos/citologia , Fibroblastos/ultraestrutura , Humanos , Concentração Inibidora 50 , Melanoma/patologia , Melanoma/ultraestrutura , Nanopartículas Metálicas/ultraestrutura , Nanofios/ultraestrutura , Espectroscopia Fotoeletrônica , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Sci Rep ; 9(1): 4096, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858407

RESUMO

Melanoma is a leading cause of high mortality that frequently spreads to the brain and is associated with deterioration in quality and quantity of life. Treatment opportunities have been restricted until now and new therapy options are urgently required. Our focus was to reveal the potential heterogeneity of melanoma brain metastasis. We succeeded to establish a brain melanoma metastasis cell line, namely MUG-Mel1 and two resulting clones D5 and C8 by morphological variety, differences in lipidome, growth behavior, surface, and stem cell markers. Mutation analysis by next-generation sequencing, copy number profiling, and cytogenetics demonstrated the different genetic profile of MUG-Mel1 and clones. Tumorigenicity was unsuccessfully tested in various mouse systems and finally established in a zebra fish model. As innovative treatment option, with high potential to pass the blood-brain barrier a peptide isolated from lactoferricin was studied in potential toxicity. Brain metastases are a major clinical challenge, therefore the development of relevant in vitro and in vivo models derived from brain melanoma metastases provides valuable information about tumor biology and offers great potential to screen for new innovative therapies.


Assuntos
Neoplasias Encefálicas/secundário , Células Clonais/patologia , Melanoma/patologia , Animais , Neoplasias Encefálicas/ultraestrutura , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Feminino , Dosagem de Genes , Humanos , Concentração Inibidora 50 , Lipídeos/análise , Masculino , Melanoma/ultraestrutura , Camundongos Nus , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Peptídeos/farmacologia , Peixe-Zebra
16.
J Eur Acad Dermatol Venereol ; 33(2): 439-446, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30242916

RESUMO

BACKGROUND: Diagnostic accuracy of reflectance confocal microscopy (RCM) as a stand-alone diagnostic tool for suspect skin lesions has not been extensively studied. OBJECTIVE: Primary aim was to measure experts' accuracy in RCM-based management decisions. Secondary aim was to identify melanoma-specific RCM features. METHODS: The study enrolled patients ≥18 years that underwent biopsy of skin lesions clinically suspected to be melanoma. One hundred lesions imaged by RCM were randomly selected from 439 lesions prospectively collected at four pigmented lesion clinics. The study data set included 23 melanomas, three basal cell and two squamous cell carcinomas, 11 indeterminate melanocytic lesions and 61 benign lesions including 50 nevi. Three expert RCM evaluators were blinded to clinical or dermoscopic images, and to the final histopathological diagnosis. Evaluators independently issued a binary RCM-based management decision, 'biopsy' vs. 'observation'; these decisions were scored against histopathological diagnosis, with 'biopsy' as the correct management decision for malignant and indeterminate lesions. A subset analysis of 23 melanomas and 50 nevi with unequivocal histopathological diagnosis was performed to identify melanoma-specific RCM features. RESULTS: Sensitivity, specificity and diagnostic accuracy were 74%, 67% and 70% for reader 1, 46%, 84% and 69% for reader 2, and 72%, 46% and 56% for reader 3, respectively. The overall kappa for management decisions was 0.34. Readers had unanimous agreement on management for 50 of the 100 lesions. Non-specific architecture, non-visible papillae, streaming of nuclei, coarse collagen fibres and abnormal vasculature showed a significant association with melanoma in the evaluation of at least two readers. CONCLUSIONS: Reflectance confocal microscopy tele-consultation of especially challenging lesions, based on image review without benefit of clinical or dermoscopy images, may be associated with limited diagnostic accuracy and interobserver agreement. Architectural and stromal criteria may emerge as potentially useful and reproducible criteria for melanoma diagnosis.


Assuntos
Melanoma/ultraestrutura , Microscopia Confocal/métodos , Nevo Pigmentado/ultraestrutura , Consulta Remota/métodos , Neoplasias Cutâneas/ultraestrutura , Centros Médicos Acadêmicos , Adulto , Idoso , Biópsia por Agulha , Institutos de Câncer , Tomada de Decisão Clínica , Dermoscopia/métodos , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/diagnóstico por imagem , Pessoa de Meia-Idade , Nevo Pigmentado/diagnóstico por imagem , Sensibilidade e Especificidade , Neoplasias Cutâneas/diagnóstico por imagem
18.
Semin Cell Dev Biol ; 73: 45-56, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28807883

RESUMO

Elucidation the nano-organization of membrane proteins at/within the plasma membrane is probably the most demanding and still challenging task in cell biology since requires experimental approaches with nanoscale resolution. During last decade, atomic force microscopy (AFM)-based simultaneous topography and recognition imaging (TREC) has become a powerful tool to quickly obtain local receptor nano-maps on complex heterogeneous biosurfaces such as cells and membranes. Here we emphasize the TREC technique and explain how to unravel the nano-landscape of mammalian cells. We describe the procedures for all steps of the experiment including tip functionalization with ligand molecules, sample preparation, and localization of key molecules on the cell surface. We also discuss the current limitations and future perspectives of this technique.


Assuntos
Membrana Celular/ultraestrutura , Microscopia de Força Atômica , Imagem Óptica , Animais , Membrana Celular/química , Humanos , Melanoma/patologia , Melanoma/ultraestrutura
19.
Cancer Cell ; 32(3): 377-391.e9, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28898698

RESUMO

How tumor-infiltrating T lymphocytes (TILs) adapt to the metabolic constrains within the tumor microenvironment (TME) and to what degree this affects their ability to combat tumor progression remain poorly understood. Using mouse melanoma models, we report that CD8+ TILs enhance peroxisome proliferator-activated receptor (PPAR)-α signaling and catabolism of fatty acids (FAs) when simultaneously subjected to hypoglycemia and hypoxia. This metabolic switch partially preserves CD8+ TILs' effector functions, although co-inhibitor expression increases during tumor progression regardless of CD8+ TILs' antigen specificity. Further promoting FA catabolism improves the CD8+ TILs' ability to slow tumor progression. PD-1 blockade delays tumor growth without changing TIL metabolism or functions. It synergizes with metabolic reprogramming of T cells to achieve superior antitumor efficacy and even complete cures.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Ácidos Graxos/metabolismo , Imunoterapia , Melanoma/imunologia , Melanoma/terapia , Microambiente Tumoral/imunologia , Animais , Antígenos CD/metabolismo , Linfócitos T CD8-Positivos/ultraestrutura , Hipóxia Celular , Progressão da Doença , Feminino , Técnicas de Silenciamento de Genes , Glucose/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Melanoma/patologia , Melanoma/ultraestrutura , Camundongos Endogâmicos C57BL , Oxigênio/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Estresse Fisiológico , Resultado do Tratamento , Proteína do Gene 3 de Ativação de Linfócitos
20.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 43(3): 216-221, abr. 2017. ilus
Artigo em Espanhol | IBECS | ID: ibc-162552

RESUMO

La incidencia de cáncer de piel está aumentando paulatinamente en el mundo desde la década de 1960. Actualmente representa un problema sanitario y económico para los diferentes sistemas de salud. La dermatoscopia es una técnica diagnóstica in vivo, no invasiva, desarrollada para estudiar las lesiones cutáneas. Mejora la precisión diagnóstica de las lesiones hiperpigmentadas y el diagnóstico precoz de las lesiones potencialmente malignas, especialmente el melanoma. No incrementa significativamente el tiempo dedicado a la exploración física. Actualmente se están descubriendo nuevas aplicaciones para esta técnica. Requiere un proceso de aprendizaje. Debido a la complejidad del tema, hemos dividido el texto en 2 partes, para intentar simplificar su exposición. Esta primera parte se centrará en los aspectos más técnicos y en las características del dispositivo denominado dermatoscopio. En la segunda parte se expondrán 2 métodos diagnósticos de sencilla interpretación y gran utilidad en Atención Primaria (AU)


The incidence of skin cancer has been gradually increasing worldwide since the 1960s. It is currently a health and economic problem for the different health systems. Dermoscopy is a non-invasive in vivo diagnostic technique, developed to study skin lesions. It improves the diagnostic accuracy of hyperpigmented lesions, as well as an early diagnosis of potentially malignant lesions, especially melanoma. The time spent on physical examination is not significantly increased. New applications have currently been discovered for this technique. Dermoscopy requires a learning process. Due to the complexity of the topic, the text has been divided into 2 parts to try to simplify its presentation. This first part will focus on the more technical aspects and the characteristics of the device called dermoscope. In the second part, 2 diagnostical methods will be presented along with their easy interpretation and usefulness in Primary Care (AU)


Assuntos
Humanos , Neoplasias Cutâneas/diagnóstico , Endoscopia , Melanoma/ultraestrutura , Hiperpigmentação/diagnóstico , Detecção Precoce de Câncer/métodos , Atenção Primária à Saúde
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