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1.
Food Chem ; 455: 139814, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38824735

RESUMO

Persimmon (Diospyros kaki) leaf is widely used as a tea substitute in East Asia, offering potential health benefits. Although studies have highlighted their effects on hyperpigmentation disorders, the active components remain unidentified. This study introduces a novel approach combining LC-MS/MS-based molecular networking with AlphaFold2-enabled virtual screening to expedite the identification of bioactive components in persimmon leaf. A total of 105 compounds were identified by MS/MS analysis. Further, virtual screening identified five flavonoids with potential anti-melanogenic properties. Bioassays confirmed myricetin, quercetin, and kaempferol inhibited melanogenesis in human melanocytes in a dose-dependent manner. Biolayer interferometry assays revealed strong binding affinity between these flavonols and hsTYR, with KD values of 23.26 ± 11.77 for myricetin, 12.43 ± 0.37 for quercetin, and 14.99 ± 3.80 µM for kaempferol. Molecular dynamics simulations provided insights into the binding interactions of these flavonols with hsTYR, particularly highlighting the essential role of the 3-OH group on the C-ring. This study elucidates the bioactive components responsible for the anti-melanogenic effects of persimmon leaf, supporting their use in product development.


Assuntos
Diospyros , Extratos Vegetais , Folhas de Planta , Espectrometria de Massas em Tandem , Diospyros/química , Folhas de Planta/química , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanócitos/química , Flavonoides/química , Flavonoides/farmacologia , Melaninas/química , Melaninas/metabolismo , Cromatografia Líquida , Espectrometria de Massa com Cromatografia Líquida
2.
Indian J Pathol Microbiol ; 66(4): 804-809, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38084536

RESUMO

Background: Cyclic adenosine monophosphate (cAMP) is an intracellular signal transmitter involved in the regulation of melanocyte growth, proliferation, and melanogenesis. R21 is a monoclonal antibody against the soluble adenylyl cyclase (sAC) protein. Various nuclear and cytoplasmic R21 expression patterns in melanocytic lesions have been previously reported. Pan-nuclear staining was defined as specific for melanoma and was found supportive in the assessment of surgical margins. Aims: The aim of this study is to evaluate the different expression patterns of R21 immunostain and investigate its effectiveness in the differential diagnosis of cutaneous malignant and benign melanocytic lesions. Settings and Design: Fifty invasive cutaneous melanoma and 50 benign melanocytic proliferation were included in the study. Materials and Methods: Paraffin blocks that best reflected tumor morphology were studied via immunohistochemical staining for R21. For all patterns, the cases showing staining in 25% or more tumor cells were considered as positive. Statistical Analysis used: Yates' Chi-square, Pearson Chi-square exact test, Spearman correlation were used. Results and Conclusions: Dot-like Golgi staining was characteristic for nevi (12/50) and seen only in one melanoma. Pan-nuclear staining was striking for melanoma (36/50). This pattern was observed in 2 dysplastic and 3 common melanocytic nevi too. None of the Spitz nevi expressed R21 in pan-nuclear pattern. For the diagnosis of melanoma, sensitivity and specificity of the pan-nuclear expression were 72% and 90%, respectively. Positive and negative predictive values were found as 87% and 76%. R21, a second-generation immunohistochemical marker, can be used in the differential diagnosis of benign and malignant melanocytic lesions.


Assuntos
Melanoma , Nevo , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico , Melanoma/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Diagnóstico Diferencial , Biomarcadores Tumorais/análise , Melanócitos/química , Melanócitos/metabolismo , Melanócitos/patologia , Nevo/diagnóstico , Nevo/patologia
3.
Lasers Surg Med ; 55(7): 680-689, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37365922

RESUMO

BACKGROUND: Dynamic in vivo changes in melanin in melasma lesions after exposure to ultraviolet (UV) irradiation have not been described. OBJECTIVES: To determine whether melasma lesions and nearby perilesions demonstrated different adaptive responses to UV irradiation and whether the tanning responses were different among different locations on face. METHODS: We collected sequential images from real-time cellular resolution full-field optical coherence tomography (CRFF-OCT) at melasma lesions and perilesions among 20 Asian patients. Quantitative and layer distribution analyses for melanin were performed using a computer-aided detection (CADe) system that utilizes spatial compounding-based denoising convolutional neural networks. RESULTS: The detected melanin (D) is melanin with a diameter >0.5 µm, among which confetti melanin (C) has a diameter of >3.3 µm and corresponds to a melanosome-rich package. The calculated C/D ratio is proportional to active melanin transportation. Before UV exposure, melasma lesions had more detected melanin (p = 0.0271), confetti melanin (p = 0.0163), and increased C/D ratio (p = 0.0152) in the basal layer compared to those of perilesions. After exposure to UV irradiation, perilesions have both increased confetti melanin (p = 0.0452) and the C/D ratio (p = 0.0369) in basal layer, and this effect was most prominent in right cheek (p = 0.030). There were however no significant differences in the detected, confetti, or granular melanin areas before and after exposure to UV irradiation in melasma lesions in all the skin layers. CONCLUSIONS: Hyperactive melanocytes with a higher baseline C/D ratio were noted in the melasma lesions. They were "fixed" on the plateau and were not responsive to UV irradiation regardless of the location on face. Perilesions retained adaptability with a dynamic response to UV irradiation, in which more confetti melanin was shed, mainly in the basal layer. Therefore, aggravating effect of UV on melasma was mainly due to UV-responsive perilesions rather than lesions.


Assuntos
Melaninas , Melanose , Humanos , Melaninas/análise , Melanócitos/química , Melanócitos/patologia , Pele/patologia , Epiderme/patologia , Raios Ultravioleta
4.
Am J Dermatopathol ; 44(1): 33-36, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33201009

RESUMO

ABSTRACT: The presence of neoplastic melanocytes within the eccrine apparatus into the reticular dermis and/or subcutaneous tissue is extremely rare. The staging of syringotropic melanomas and their biological behavior are still controversial. We present 6 new cases of syringotropic melanoma and their main histopathologic features; review the previous literature; and discuss about the origin, staging, and prognosis of this rare variant of melanoma.


Assuntos
Melanócitos/patologia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Glândulas Sudoríparas/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanócitos/química , Melanoma/química , Melanoma/cirurgia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Neoplasias Cutâneas/química , Neoplasias Cutâneas/cirurgia , Glândulas Sudoríparas/química , Glândulas Sudoríparas/cirurgia , Resultado do Tratamento
5.
Nucleic Acids Res ; 49(8): 4266-4280, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33849058

RESUMO

Cyclobutane pyrimidine dimers (CPDs) are the major products of DNA produced by direct absorption of UV light, and result in C to T mutations linked to human skin cancers. Most recently a new pathway to CPDs in melanocytes has been discovered that has been proposed to arise from a chemisensitized pathway involving a triplet sensitizer that increases mutagenesis by increasing the percentage of C-containing CPDs. To investigate how triplet sensitization may differ from direct UV irradiation, CPD formation was quantified in a 129-mer DNA designed to contain all 64 possible NYYN sequences. CPD formation with UVB light varied about 2-fold between dipyrimidines and 12-fold with flanking sequence and was most frequent at YYYR and least frequent for GYYN sites in accord with a charge transfer quenching mechanism. In contrast, photosensitized CPD formation greatly favored TT over C-containing sites, more so for norfloxacin (NFX) than acetone, in accord with their differing triplet energies. While the sequence dependence for photosensitized TT CPD formation was similar to UVB light, there were significant differences, especially between NFX and acetone that could be largely explained by the ability of NFX to intercalate into DNA.


Assuntos
Região 3'-Flanqueadora , Região 5'-Flanqueadora , DNA/química , DNA/efeitos da radiação , Fármacos Fotossensibilizantes/química , Dímeros de Pirimidina/química , Sequência de Bases , Citosina/química , Humanos , Melanócitos/química , Melanócitos/efeitos da radiação , Mutagênese , Mutação , Neoplasias Cutâneas/genética , Timina/química , Raios Ultravioleta
6.
Am J Surg Pathol ; 45(7): 962-968, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33264137

RESUMO

Clear cell morphology is an uncommon finding in tumors. A subset of clear cell neoplasms also shows melanocytic differentiation, including clear cell sarcoma, PEComa, and some subtypes of renal cell carcinoma. A hallmark of these tumor types is the activation of a member of the MIT/TFE family of transcription factors, which includes MITF, TFE3, TFEB, and TFEC. Microphthalmia transcription factor (MITF is the master regulator of melanin synthesis, while TFEB plays a critical role in lysosome biogenesis. Cytogenetic translocations involving TFE3 and TFEB are now well described in multiple tumor types, but there has been little evidence to suggest similar regulation of MITF. Here we describe a series of 7 clear cell cutaneous neoplasms with melanocytic differentiation that are characterized by ACTIN-MITF gene fusions, either ACTB-MITF or ACTG1-MITF. The chromosomal breakpoints preserve MITF's dimerization and transcriptional activation domains, suggesting that these fusion proteins likely result in hyperactive MITF function, analogously to the previously reported TFE3 and TFEB fusions. Our findings indicate that MITF gene rearrangements may be key drivers of tumor pathogenesis and expand the spectrum of neoplasia associated with the MIT/TFE family.


Assuntos
Biomarcadores Tumorais/genética , Diferenciação Celular , Rearranjo Gênico , Melanócitos/patologia , Proteínas de Fusão Oncogênica/genética , Neoplasias Cutâneas/genética , Translocação Genética , Adolescente , Adulto , Idoso , Boston , Feminino , França , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Melanócitos/química , Pessoa de Meia-Idade , Fenótipo , Estudos Retrospectivos , Análise de Sequência de RNA , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia
7.
Am J Dermatopathol ; 43(4): 273-277, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32675472

RESUMO

ABSTRACT: Lentigo maligna (LM) represents an overgrowth of atypical melanocytes at the dermal-epidermal junction of chronically sun-damaged skin. The presence of LM on sun-damaged skin poses a diagnostic challenge because the solar-induced melanocytic hyperplasia makes it difficult to assess the LM margins. Melanocytic density can be used to discriminate sun-damaged skin from LM. The aim of this study was to quantify the melanocytic density at the surgical margins of scanned whole-slide images of LM comparing sections stained with H&E and SOX10. Twenty-six surgically excised LM diagnosed at the Department of Pathology at Sahlgrenska University Hospital were collected. The slides that contained the closest surgical margin or harbored the highest density of melanocytes at the margin were selected for serial sectioning using H&E and SOX10. Whole-slide imaging at ×40 magnification was used, and a circular field with a diameter of 0.5 mm at the surgical margin was superimposed on the image. Five blinded pathologists reviewed the slides in a randomized order. In the majority of the cases (24/26), the pathologists identified more melanocytes on the SOX10 slides than those on the H&E slides. On average, 2.5 times more melanocytes were counted using SOX10 compared with H&E (P < 0.05). Furthermore, the average group SD on the H&E slides was 4.12 compared with 2.83 on the SOX10 slides (P = 0.004). Thus, the use of SOX10 staining leads to higher melanocytic density counts compared with H&E staining when assessing the surgical margins of LM. The use of SOX10 staining also significantly decreased the interobserver variability between pathologists.


Assuntos
Biomarcadores Tumorais/análise , Proliferação de Células , Sarda Melanótica de Hutchinson/química , Imuno-Histoquímica , Melanócitos/química , Microscopia , Fatores de Transcrição SOXE/análise , Neoplasias Cutâneas/química , Coloração e Rotulagem , Corantes , Amarelo de Eosina-(YS) , Hematoxilina , Humanos , Sarda Melanótica de Hutchinson/patologia , Interpretação de Imagem Assistida por Computador , Melanócitos/patologia , Variações Dependentes do Observador , Patologistas , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Neoplasias Cutâneas/patologia
8.
Am J Dermatopathol ; 43(4): 252-258, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33201012

RESUMO

BACKGROUND: Atypical intraepidermal melanocytic proliferation (AIMP) is a general term assigned to melanocytic proliferations of uncertain biological potential when a definitive histopathological diagnosis cannot be achieved. There are few data available describing the possibility of malignancy of AIMP, or ways to further define diagnosis. OBJECTIVE: To determine the rate of diagnostic change of AIMP to melanoma or melanoma in situ (MIS) after conventional excision. In addition, to determine the role of immunohistochemistry (IHC) in defining AIMP biopsies. METHODS: Retrospective cross-sectional, single-center review of biopsies with a diagnosis of AIMP with a follow-up conventional excision from 2012-2016 was performed. In a separate analysis, a search was performed for AIMP biopsied lesions in which IHC was subsequently performed. RESULTS: The rate of diagnostic change of AIMP to MIS was 4.8% (8/167) after excision. Punch biopsy was a risk factor for diagnostic change to MIS (odds ratio 12.94, confidence interval 2.56-65.38, P = 0.008). The rate of diagnostic change of AIMP biopsies after examining with IHC was 21.3% (34/160) to MIS and 4.4% (7/160) to melanoma. CONCLUSION: The possibility of malignancy of AIMP lesions must be taken into consideration when counseling patients and when planning treatment options. IHC is a useful tool and should be used in the evaluation of AIMP specimens.


Assuntos
Proliferação de Células , Melanócitos/patologia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Terminologia como Assunto , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Masculino , Melanócitos/química , Melanoma/química , Melanoma/classificação , Melanoma/cirurgia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Neoplasias Cutâneas/química , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/cirurgia , Adulto Jovem
9.
Am J Dermatopathol ; 42(12): 956-960, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32809978

RESUMO

Melanomas with complete histological regression have been seen very infrequently. On the other hand, the diagnosis of metastatic melanoma is based on the histopathology and positivity of markers such as S100, Melan-A, and HMB-45 whose sensitivity is 99%, 82%, and 76%, respectively. It is very rare that metastatic melanomas and even more primary melanoma are negative for all of these markers. In these rare cases, there is usually a known primary. We present the case of a 82-year-old woman with a erythematous mass in the left groin and a 1-cm black-bluish irregular nodule on the skin of the ipsilateral foot. This lesion was clinical and dermoscopically compatible with primary melanoma. In the histological evaluation of the skin, a dermis full of melanophages and hemosiderophages were found in a background of fibrosis, scarce lymphocytic infiltrate, and neovascularization. Any cells expressing melanocytic markers were observed. It was diagnosed as tumoral melanosis. Lymph nodes showed a proliferation of atypical epithelioid cells with eosinophilic cytoplasm. Mitosis was conspicuous. Tumoral cells were vimentin and CD99 positive, and S100, CD34, HMB-45, Melan-A, SOX 10, tyrosinase, C-KIT, CD45, and CKAE1/AE3 negative, and BRAF-V600 mutated was detected. During follow-up, atypical vitiligo-like lesions were discovered, suggesting the diagnosis of metastatic melanoma totally regressed in our patient.


Assuntos
Biomarcadores Tumorais/análise , Melanócitos/química , Melanoma/química , Melanose/metabolismo , Neoplasias Cutâneas/química , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Evolução Fatal , Feminino , Humanos , Metástase Linfática , Melanócitos/patologia , Melanoma/genética , Melanoma/secundário , Melanose/genética , Melanose/patologia , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
10.
Mol Med Rep ; 22(2): 733-738, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32626944

RESUMO

Melanogenesis is the synthesis of the skin pigment melanin, which serves a critical role in the study of pigmentary skin diseases. Syntenin has been identified as a melanosome protein, but its role in melanogenesis is not completely understood. The present study aimed to investigate the effects and mechanisms underlying syntenin on melanogenesis in immortalized human melanocytes. Depletion of syntenin expression increased both tyrosinase (Tyr) activity and melanin content. Syntenin silencing also increased the protein expression levels of Tyr, pre­melanosomal protein and microphthalmia­associated transcription factor. In addition, the results indicated that syntenin regulated melanogenesis by upregulating the phosphorylation of p38 mitogen­activated protein kinase (p38 MAPK). Taken together, these findings suggested that the regulation of melanogenesis by syntenin may be mediated by the activation of p38 MAPK and that syntenin might provide new insights into the pathogenesis of pigmented diseases.


Assuntos
Melaninas/biossíntese , Melanócitos/química , Melanócitos/metabolismo , Transdução de Sinais , Sinteninas/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Diferenciação Celular , Células Cultivadas , Técnicas de Silenciamento de Genes , Humanos , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Fosforilação , Pigmentação/fisiologia , Sinteninas/antagonistas & inibidores , Regulação para Cima , Antígeno gp100 de Melanoma/metabolismo
11.
J Nat Prod ; 83(1): 79-87, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31886665

RESUMO

The effects of a single-amino-acid culture strategy on secondary metabolite production in the marine-derived fungus Trichoderma erinaceum F1-1 were investigated by culturing the fungus in GPY medium supplemented or not supplemented with l-phenylalanine. A suite of secondary metabolites, including seven terpenoids (1-7) and one polyketide (8), among which are four new compounds, harziandione A (1), cyclonerodiols A and B (3, 4), and trichodermaerin A (6), were isolated from the GPY medium without l-phenylanine, whereas 18 aromatic compounds (9-26), including six new compounds, trichoderolides A-F (9, 10, and 14-17), were isolated from the culture grown in the GPY medium with l-phenylalanine. The structures of the new compounds were determined by high-resolution mass spectrometry, NMR spectroscopic analysis, optical rotation calculations, chemical methods, and X-ray crystallography. Compounds 10, 12, 13, and 26 exhibited cytotoxic activities against MDA-MB-435 human melanocyte cancer cells. Compound 26 was cytotoxic to A549 adenocarcinomic human alveolar basal epithelial cells.


Assuntos
Antineoplásicos/farmacologia , Diterpenos/química , Hypocreales/química , Lactonas/química , Melanócitos/química , Fenilalanina/química , Antineoplásicos/química , Humanos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas , Melanócitos/efeitos dos fármacos , Estrutura Molecular , Policetídeos/química
12.
Methods Mol Biol ; 2095: 303-317, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31858476

RESUMO

Raman microscopy is an emerging tool in biomedicine. It provides label-free and non-invasive analysis of biological cells. Due to its high biochemical specificity, Raman spectroscopy can be used to acquire spectral fingerprints that allow characterizing cells types and states. Here, we present a methodological approach for implementing Raman microscopy in skin cell measurements. Raman spectra can clearly identify keratinocytes, fibroblasts, and melanocytes cells that are involved in the production of autologous skin grafts. Consequently, Raman microscopy is a promising tool that can be used to analyze single cells and to test the quality of therapeutic cell products.


Assuntos
Fibroblastos/química , Queratinócitos/química , Melanócitos/química , Microscopia/métodos , Análise Espectral Raman/métodos , Células Cultivadas , Humanos , Microscopia/instrumentação , Pele/química , Software , Análise Espectral Raman/instrumentação
13.
Sci Rep ; 9(1): 18585, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31819095

RESUMO

Choroidal melanocytes (HCMs) are melanin-producing cells in the vascular uvea of the human eye (iris, ciliary body and choroid). These cranial neural crest-derived cells migrate to populate a mesodermal microenvironment, and display cellular functions and extracellular interactions that are biologically distinct to skin melanocytes. HCMs (and melanins) are important in normal human eye physiology with roles including photoprotection, regulation of oxidative damage and immune responses. To extend knowledge of cytoplasmic melanins and melanosomes in label-free HCMs, a non-invasive 'fit-free' approach, combining 2-photon excitation fluorescence lifetimes and emission spectral imaging with phasor plot segmentation was applied. Intracellular melanin-mapped FLIM phasors showed a linear distribution indicating that HCM melanins are a ratio of two fluorophores, eumelanin and pheomelanin. A quantitative histogram of HCM melanins was generated by identifying the image pixel fraction contributed by phasor clusters mapped to varying eumelanin/pheomelanin ratio. Eumelanin-enriched dark HCM regions mapped to phasors with shorter lifetimes and longer spectral emission (580-625 nm) and pheomelanin-enriched lighter pigmented HCM regions mapped to phasors with longer lifetimes and shorter spectral emission (550-585 nm). Overall, we demonstrated that these methods can identify and quantitatively profile the heterogeneous eumelanins/pheomelanins within in situ HCMs, and visualize melanosome spatial distributions, not previously reported for these cells.


Assuntos
Corioide/química , Melaninas/química , Melanócitos/química , Microscopia/métodos , Idoso , Citoplasma/química , Feminino , Fundo de Olho , Células HEK293 , Humanos , Masculino , Melanoma/química , Melanossomas/química , Pessoa de Meia-Idade , NAD/química , Fótons , Pigmentação , Neoplasias Cutâneas/química
14.
Am J Surg Pathol ; 43(10): 1368-1376, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31162285

RESUMO

Recurrent activating Gαq mutations in the spectrum of blue nevi have been well studied. However, the clinicopathologic characteristics of the recently described CYSLTR2-mutant and PLCB4-mutant blue nevi remain limited, owing to their rarity. Herein, we present 7 CYSLTR2-mutant melanocytic neoplasms, including 1 cellular blue nevus, 4 atypical cellular blue nevi, and 2 blue nevus-like melanomas. They occurred on the scalp, breast, flank, forearm, thigh, leg, and ankle of 3 male patients and 4 female patients, with a median age of 43 (25 to 81) years at diagnosis. Five exhibited an exophytic growth, and 6 were heavily pigmented. A fascicular arrangement of medium to large spindle melanocytes was seen in 6 cases, but epithelioid cytology was present in only 2 cases, one of them being focal. A junctional component was present in 3 cases. Immunoreactivity for HMB45 was diffusely present, except in 1 cellular blue nevus. BAP1 nuclear immunoexpression was lost in 1 melanoma case. A canonical CYSLTR2 L129Q hotspot mutation was present in all cases. Altogether, these histopathologic findings suggest that CYSLTR2-mutant melanocytic blue neoplasms frequently exhibit a heavily pigmented exophytic tumor with a silhouette resembling "pigmented epithelioid melanocytoma" rather than usual cellular blue nevus. Moreover, most of these tumors were not clinically recognized as blue nevi and not located in the classic topography of cellular blue nevus aside from the scalp. However, a fascicular arrangement of medium to large-sized spindled melanocytes, as well as a lack of epithelioid or nevoid melanocytes, could be potential diagnostic clues to morphologically distinguish CYSLTR2-mutant tumors from "pigmented epithelioid melanocytoma."


Assuntos
Biomarcadores Tumorais/genética , Melanócitos/patologia , Mutação , Nevo Azul/genética , Receptores de Leucotrienos/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Diagnóstico Diferencial , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Melanócitos/química , Antígenos Específicos de Melanoma/análise , Pessoa de Meia-Idade , Nevo Azul/química , Nevo Azul/classificação , Nevo Azul/patologia , Valor Preditivo dos Testes , Neoplasias Cutâneas/química , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/patologia , Proteínas Supressoras de Tumor/análise , Ubiquitina Tiolesterase/análise , Antígeno gp100 de Melanoma
15.
Br J Biomed Sci ; 76(4): 172-177, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31144600

RESUMO

Background: The diagnosis of heavily pigmented melanocytic lesions is problematic. This is often compounded by lack of visibility of nuclear detail of tumour cells due to physical masking by melanin pigment. Similarly, there can be colour merging of chromogenic final reaction products with melanin, making an evidence of antigenic localisation problematic. There are a number of melanin bleaching techniques available for immunohistochemical assessments.Material and methods: All methods to date have involved the bleaching of melanin as a manually performed primary step before loading subsequently bleached slides onto automated immunohistochemical platforms. Here we define a semi-automated bleaching procedure that allows full integration on one of the most widely employed automated IHC staining platforms (Roche Ventana BenchMark Ultra). The bleaching protocol was defined on the BenchMark Ultra and involved the assessment of 24 histological cases of heavily pigmented malignant melanoma lesions (13 cutaneous and 11 metastatic) routinely fixed processed and paraffin wax embedded.Results: Completion of the bleaching was assessed on H&E preparations performed following the semi-automated bleaching step and employing the Roche Ventana BenchMark Ultra machine for 60 min at 42°C. Complete immunohistochemical staining was achieved on the automated platform within 5-6 h including the bleaching step. Results were consistent across all tissue evaluated.Discussion: This data provides evidence that the hydrogen peroxide bleaching procedure can be adapted for integration on one of the most widely employed automated IHC staining platforms and as a result, improve the efficiency and reproducibility of the technique.


Assuntos
Automação Laboratorial/normas , Clareadores/química , Peróxido de Hidrogênio/química , Imuno-Histoquímica/normas , Melaninas/química , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Anticorpos/química , Amarelo de Eosina-(YS) , Hematoxilina , Humanos , Melaninas/biossíntese , Melanócitos/química , Melanócitos/patologia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
16.
Anat Histol Embryol ; 48(4): 296-305, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30916435

RESUMO

The purpose of the present study was to define the applicability of tissue clearing to the field of otology. We combined tissue clearing with vital staining perfusion via a pumping system to examine the vascular anatomy of temporal bones in laboratory animals. We used six different types of species including Korean wild mouse, mouse, Mongolian gerbil, hamsters and Guinea pigs. A mixture of Alcian blue reagent and 4% paraformaldehyde was circulated throughout the entire circulatory system of the animal via a perfusion pump system. Transparency images were obtained from the temporal bones according to the protocol of the SunHyun 3D Imaging Kit. In examining the inner surface of the tympanic membrane, flaccid part (pars flaccida) was positioned along the entire marginal area in Guinea pig. In the Guinea pig, unlike the other species, the cortical bone of the mastoid (bullae) was easily removed using cold instruments, allowing a direct approach to the enclosed structures. The distribution and pattern of cochlea melanocytes were compared among the species. "Mobius strip"-like accumulated melanocytes in vestibules were shown in both the Korean wild mouse and mouse. The collateral blood supply to the cochlea in six different species was checked in various pattern. Combining dye infusion with tissue-clearing techniques, we documented the middle ear and transparent inner ear structures in six different species. The information and associated images will help other researchers to develop hypotheses and design experimental investigations.


Assuntos
Animais de Laboratório/anatomia & histologia , Gerbillinae/anatomia & histologia , Cobaias/anatomia & histologia , Mesocricetus/anatomia & histologia , Camundongos/anatomia & histologia , Osso Temporal/anatomia & histologia , Azul Alciano , Animais , Corantes , Cricetinae , Fixadores , Formaldeído , Masculino , Melanócitos/química , Melanócitos/citologia , Camundongos Endogâmicos C57BL/anatomia & histologia , Otolaringologia/métodos , Polímeros , Coloração e Rotulagem/veterinária , Osso Temporal/irrigação sanguínea , Osso Temporal/citologia
17.
Ann Dermatol Venereol ; 146(5): 372-376, 2019 May.
Artigo em Francês | MEDLINE | ID: mdl-30910333

RESUMO

BACKGROUND: Myxoid melanoma is a rare variant of melanoma that must be recognised. Herein we describe a new metastatic case. PATIENTS AND METHODS: A 78-year-old woman consulted for a firm, pinkish nodule measuring 25mm and present for six months on her left leg. Analysis of the biopsy revealed achromic fusiform tumour cells separated by large myxoid plaques. Labeling of SOX10, HMB45 and PS100 was diffuse and of moderate to strong intensity. A diagnosis of myxoid melanoma was considered, with Breslow thickness of 9mm. Surgery was carried out with a 2-cm margin and confirmed the diagnosis. Dermatological follow-up at one year revealed metastatic spread to the ganglia, pleura, liver and bone. DISCUSSION: Few cases of primary myxoid melanoma have been described, and the condition is probably underdiagnosed. The classic clinical presentation of this condition consists of a solitary achromic nodule found chiefly on the limbs. The microscopic appearance is relatively non-specific. Immunohistochemical analysis may indicate melanocytic involvement: cells exhibit expression of SOX10, diffuse expression of protein S100, and less consistent and more variable expression of HMB45. The increasingly common use of anti-SOX10 is of value since it is expressed in the nucleus of melanocytes. Mastocytes and TGF-ß secretion appear to be involved in myxoid stroma production. In the absence of specific codification, management of myxoid melanoma is comparable to that of other types of melanoma. There is uncertainty about the prognosis, with the involvement of TGF-ß possibly indicating the aggressive potential of this type of tumour.


Assuntos
Perna (Membro) , Melanoma/patologia , Neoplasias Cutâneas/patologia , Idoso , Biomarcadores Tumorais/análise , Biópsia , Feminino , Humanos , Melanócitos/química , Melanoma/química , Antígenos Específicos de Melanoma/análise , Proteínas S100/análise , Fatores de Transcrição SOXE/análise , Neoplasias Cutâneas/química , Antígeno gp100 de Melanoma
18.
Genes (Basel) ; 11(1)2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31905971

RESUMO

Skin is the body's largest organ, and the main function of skin is to protect underlying organs from possible external damage. Melanocytes play an important role in skin pigmentation. The Bama pig has a "two-end-black" phenotype with different coat colors across skin regions, e.g., white skin (without melanocytes) and black skin (with melanocytes), which could be a model to investigate skin-related disorders, specifically loss of melanocytes. Here, we generated expression profiles of mRNAs and long noncoding RNAs in Bama pig skins with different coat colors. In total, 14,900 mRNAs and 7549 lncRNAs were expressed. Overall, 2338 mRNAs/113 lncRNAs with FDR-adjusted p-value ≤ 0.05 were considered to be differentially expressed (DE) mRNAs/lncRNAs, with 1305 down-regulated mRNAs and 1033 up-regulated mRNAs in white skin with|log2(fold change)| > 1. The genes down-regulated in white skin were associated with pigmentation, melanocyte-keratinocyte interaction, and keratin, while up-regulated ones were mainly associated with cellular energy metabolisms. Furthermore, those DE lncRNAs were predicted to be implicated in pigmentation, keratin synthesis and cellular energy metabolism. In general, this study provides insight into the transcriptional difference involved in melanocyte-loss-induced keratinocyte changes and promotes the Bama pig as a biomedical model in skin research.


Assuntos
Perfilação da Expressão Gênica/métodos , Melanócitos/citologia , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Pele/química , Animais , Metabolismo Energético , Regulação da Expressão Gênica , Melanócitos/química , Fenótipo , Análise de Componente Principal , Análise de Sequência de RNA , Pele/citologia , Pigmentação da Pele , Suínos
19.
Am J Dermatopathol ; 41(1): 45-49, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29894358

RESUMO

Extramammary Paget disease (EMPD) is a rare intraepithelial carcinoma and an uncommon variant of Paget disease affecting areas of the apocrine-rich skin of the perineum, vulva, and less commonly, axilla. Women in their sixth to eighth decades are commonly affected. It is exceedingly rare for EMPD to present on the face, chest, abdomen, or other nonapocrine sites and even more unusual for EMPD to present as a pigmented lesion. The relationship between Paget cells in pigmented extramammary Paget disease (PEMPD) and reactive proliferation and colonization by melanocytes has been poorly explored. The relevance of this rare entity resides in its potential to be misdiagnosed clinically and histopathologically as malignant melanoma in situ. Therefore, application of a panel of immunostains and careful analysis and interpretation of these findings are essential to arrive at the correct diagnosis. We report a new case of PEMPD on a nonapocrine site. The specimen was examined by routine microscopy including hematoxylin and eosin stain as well as immunostains. Histologic examination revealed characteristic features of PEMPD confirmed with immunohistochemical stains.


Assuntos
Neoplasias Abdominais/patologia , Melanócitos/patologia , Melanoma/patologia , Doença de Paget Extramamária/patologia , Neoplasias Cutâneas/patologia , Neoplasias Abdominais/química , Idoso , Biomarcadores Tumorais/análise , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Melaninas/análise , Melanócitos/química , Melanoma/química , Doença de Paget Extramamária/química , Valor Preditivo dos Testes , Neoplasias Cutâneas/química
20.
Transl Res ; 204: 72-81, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30342000

RESUMO

Overexpression of SMAD7-a hallmark inhibitor of transforming growth factor ß (TGFß) signaling-has been documented and related with adverse prognosis in a number of epithelial malignancies, suggesting that it may be responsible for resistance to TGFß-induced growth arrest of cancer cells. The involvement of SMAD7 in development and progression of malignant melanoma is unclear, and its expression has not been characterized so far at the protein level in clinical melanoma tissue samples. We evaluated SMAD7 expression in 205 skin melanoma primary tumors by immunohistochemistry and correlated the findings with clinicopathological profiles of patients. Melanocytic SMAD7 was evidenced in 204 cases, and the expression pattern was predominantly nuclear. High expression of SMAD7 was positively associated with several features of tumor aggressiveness, for example, presence of ulceration (P < 0.001), higher tumor thickness (P < 0.001), and mitotic rate (P < 0.001), but not presence of regional or distant metastases. Moreover, high SMAD7 expression independently predicted unfavorable outcome: melanoma-specific survival (hazard ratio = 3.16, P < 0.001) and recurrence-free survival (hazard ratio = 2.88, P < 0.001). Taken together, our results underline the importance of TGFß signaling in cancer and define SMAD7 as a marker of aggressive tumor behavior and adverse clinical outcomes in melanoma patients.


Assuntos
Melanoma/mortalidade , Neoplasias Cutâneas/mortalidade , Proteína Smad7/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanócitos/química , Melanoma/química , Melanoma/patologia , Pessoa de Meia-Idade , Transdução de Sinais/fisiologia , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia , Proteína Smad7/análise , Fator de Crescimento Transformador beta/fisiologia , Adulto Jovem
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