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1.
Plast Reconstr Surg Glob Open ; 12(1): e5487, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38268720

RESUMO

Background: Deep inferior epigastric perforator (DIEP) flap breast reconstruction leads to large scars in the breast and abdominal region. Common symptoms related to abdominal scarring include changes in color, stiffness, thickness, and irregularity of the skin. The aim of this study was to examine whether microneedling improves the abdominal scar quality after DIEP-flap breast reconstruction. Methods: A prospective randomized controlled within subject comparison design (N = 30) was used to study the effect of microneedling treatments on the abdominal scar, versus no treatment. Three electrically powered microneedling sessions were performed every 4 weeks on one side of the abdominal scar. Abdominal scar assessment was performed at baseline and 3-, 6-, and 9-month follow-up using the Patient and Observer Scar Assessment Scale (POSAS). Treated and untreated sides were compared using a t test or Wilcoxon signed-rank test in case the data were not normally distributed. Results: Twenty-seven women completed the study. Microneedling treatment led to lower POSAS scores compared with the untreated scar side after the 3- and 9-month follow-up. At the 9-month follow-up, the POSAS total score (Mdn = 17, interquartile range = 18.3 versus Mdn = 21.4, interquartile range = 17.5) was statistically lower for the treated side compared with the untreated side, implying a better-appraised scar quality. The observer POSAS total score was statistically lower for the treated side compared with the untreated side. Conclusions: Based on patient and observer ratings, overall abdominal scars after DIEP-flap surgery improve significantly after microneedling treatment. Scar symptoms reduce faster under the influence of microneedling treatment compared with no treatment.

2.
J Plast Reconstr Aesthet Surg ; 75(6): 1805-1812, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35125306

RESUMO

PURPOSE: This research aimed to explore factors associated with patient-reported breast and abdominal scar quality after deep inferior epigastric perforator (DIEP) flap breast reconstruction (BR). MATERIAL AND METHODS: This study was designed as a descriptive cross-sectional survey in which women after DIEP flap BR were invited to complete an online survey on breast and abdominal scarring. The online survey was distributed in the Netherlands in several ways in order to reach a diverse population of women. Outcomes were assessed with the Patient Scale of the Patient and Observer Scar Assessment Scale (POSAS). Additional items were assessed with a numeric rating scale (NRS). RESULTS: A total of 248 women completed the survey. There was a statistically significant worse POSAS scar appraisal for the abdominal scar compared with the breast scar. The vast majority of women reported high scores on at least one scar characteristic of their breast scar or abdominal scar. Overall, color, stiffness, thickness, and irregularity scored higher than pain and itching. Women were only moderately positive about the size, noticeability, location, and the information provided regarding scarring. CONCLUSION: It is crucial to address the inevitability of scars in patient education before a DIEP flap BR, with a particular focus on the abdominal scar, as women experience abdominal scars significantly worse than their breast scars. Providing more information on the experience of other women and the expected appearance will contribute to having realistic expectations while allowing them to make well-informed decisions.


Assuntos
Mamoplastia , Retalho Perfurante , Cicatriz/cirurgia , Estudos Transversais , Artérias Epigástricas/cirurgia , Feminino , Humanos , Mamoplastia/efeitos adversos , Medidas de Resultados Relatados pelo Paciente , Retalho Perfurante/cirurgia , Estudos Retrospectivos
3.
Exp Dermatol ; 31(4): 556-566, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34758170

RESUMO

Mounting evidence shows that the PD-1/PD-L1 axis is involved in tumor immune evasion. This is demonstrated by anti-PD-1 antibodies that can reverse tumor-associated PD-L1 to functionally suppress anti-tumor T-cell responses. Since type I and II interferons are key regulators of PD-L1 expression in melanoma cells and IFN-γ-producing CD8+ T cells and IFN-α-producing dendritic cells are abundant in vitiligo skin, we aimed to study the role of PD-1/PD-L1 signalling in melanocyte destruction in vitiligo. Moreover, impaired PD-1/PD-L1 function is observed in a variety of autoimmune diseases. It is, therefore, hypothesized that manipulating PD-1/PD-L1 signalling might have therapeutic potential in vitiligo. The PD-1+ T cells were abundantly present in situ in perilesional vitiligo skin, but expression of PD-L1 was limited and confined exclusively to dermal T cells. More specifically, neither melanocytes nor other epidermal skin cells expressed PD-L1. Exposure to IFN-γ, but also type I interferons, increased PD-L1 expression in primary melanocytes and fibroblasts, derived from healthy donors. Primary human keratinocytes only showed increased PD-L1 expression upon stimulation with IFN-γ. More interestingly, melanocytes derived from non-lesional vitiligo skin showed no PD-L1 upregulation upon IFN-γ exposure, while other skin cells displayed significant PD-L1 expression after exposure. In a vitiligo skin explant model, incubation of non-lesional vitiligo skin with activated (IFN-γ-producing) T cells from vitiligo lesions was previously described to induce melanocyte apoptosis. Although PD-L1 expression was induced in epidermal cells in these explants, this induction was completely absent in melanocytes. The lack of PD-L1 upregulation by melanocytes in the presence of IFN-γ-producing T cells shows that melanocytes lack protection against T-cell attack during vitiligo pathogenesis. Manipulating PD-1/PD-L1 signalling may, therefore, be a therapeutic option for vitiligo patients.


Assuntos
Vitiligo , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos , Humanos , Interferon gama/metabolismo , Melanócitos/metabolismo , Receptor de Morte Celular Programada 1/metabolismo
4.
J Cancer Surviv ; 15(2): 224-233, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32816201

RESUMO

PURPOSE: The purpose of this research was to explore women's experiences after breast surgery with scar characteristics and symptoms, and its impact on their health-related quality of life (HRQOL). MATERIAL AND METHODS: A qualitative study using semi-structured face-to-face interviews was conducted among women following prophylactic, oncologic, or reconstructive breast surgery in the Netherlands. A directed content analysis was performed using guiding themes. Themes were "physical and sensory symptoms," "impact of scar symptoms," "personal factors," "impact of scar interventions," and "change over time." RESULTS: The study population consisted of 26 women after breast surgery. Women experienced a wide range of symptoms like adherence, stiffness, pain, and uncomfortable sensations. Scar characteristics as visibility, location, texture, and size, influenced satisfaction with their appearance. The impact of scar symptoms is reflected in physical, social, emotional, and cognitive functioning, thereby affecting HRQOL. The experienced impact on HRQOL depended on several factors, like personal factors as the degree of acceptance and environmental factors like social support. CONCLUSION: Women can experience a diversity of scar characteristics and symptoms, which play a central role in the perceived impact on HRQOL. Since scarring can have a considerable impact on HRQOL, scarring after prophylactic, oncologic and reconstructive breast surgery should be given more attention in clinical practice and research. IMPLICATIONS FOR CANCER SURVIVORS: Considering scarring as a common late effect after breast surgery and understanding the variety of experiences, which could impact HRQOL of women, can be beneficial in sufficient information provision, expectation management, and informed decision making.


Assuntos
Neoplasias da Mama , Qualidade de Vida , Neoplasias da Mama/cirurgia , Cicatriz , Feminino , Humanos , Mastectomia , Pesquisa Qualitativa
5.
Oncoimmunology ; 7(4): e1419113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29632737

RESUMO

Vitiligo development in melanoma patients during immunotherapy is a favorable prognostic sign and indicates breakage of tolerance against melanocytic/melanoma antigens. We investigated a novel immunotherapeutic approach of the skin-depigmenting compound monobenzone synergizing with imiquimod in inducing antimelanoma immunity and melanoma regression. Stage III-IV melanoma patients with non-resectable cutaneous melanoma metastases were treated with monobenzone and imiquimod (MI) therapy applied locally to cutaneous metastases and adjacent skin during 12 weeks, or longer. Twenty-one of 25 enrolled patients were evaluable for clinical assessment at 12 weeks. MI therapy was well-tolerated. Partial regression of cutaneous metastases was observed in 8 patients and stable disease in 1 patient, reaching the statistical endpoint of treatment efficacy. Continued treatment induced clinical response in 11 patients, including complete responses in three patients. Seven patients developed vitiligo-like depigmentation on areas of skin that were not treated with MI therapy, indicating a systemic effect of MI therapy. Melanoma-specific antibody responses were induced in 7 of 17 patients tested and melanoma-specific CD8+T-cell responses in 11 of 15 patients tested. These systemic immune responses were significantly increased during therapy as compared to baseline in responding patients. This study shows that MI therapy induces local and systemic anti-melanoma immunity and local regression of cutaneous metastases in 38% of patients, or 52% during prolonged therapy. This study provides proof-of-concept of MI therapy, a low-cost, broadly applicable and well-tolerated treatment for cutaneous melanoma metastases, attractive for further clinical investigation.

6.
Pigment Cell Melanoma Res ; 27(6): 1086-96, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25043574

RESUMO

Patients with melanoma may develop skin depigmentation spontaneously or following therapy, referred to as melanoma-associated leucoderma (MAL). As clinical presentation of MAL may precede primary/metastatic melanoma detection, recognition of MAL is important to prevent its misdiagnosis as vitiligo and the subsequent application of immunosuppressive treatment. To reveal the immunity involved in MAL development, we investigated the presence of antibody and T-cell immune responses directed against the melanocyte-differentiation-antigens MART-1 (Melan-A), tyrosinase and gp100 in patients with MAL, as compared to patients with vitiligo. Autoantibodies to gp100 and tyrosinase were commonly found in both diseases. Interestingly, MART-1 antibodies were only present in patients with MAL. Melanocyte antigen-specific T cells were found in all patients, with relatively more specific T cells in patients with active vitiligo. Although MAL and vitiligo may appear clinically similar, our results indicate that the humoral immune responses against MART-1 differ between these diseases, which can help to differentiate MAL from vitiligo.


Assuntos
Formação de Anticorpos/imunologia , Hipopigmentação/complicações , Hipopigmentação/imunologia , Antígeno MART-1/imunologia , Melanoma/complicações , Melanoma/imunologia , Vitiligo/imunologia , Adolescente , Adulto , Idoso , Especificidade de Anticorpos/imunologia , Linfócitos T CD8-Positivos/imunologia , Demografia , Feminino , Humanos , Masculino , Melanócitos/imunologia , Melanócitos/patologia , Melanoma/patologia , Pessoa de Meia-Idade , Vitiligo/patologia , Adulto Jovem
7.
Cancer Immunol Res ; 2(6): 538-46, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24894091

RESUMO

In this study, we investigated a large series of immune (escape) markers, relevant to T-cell function, as potential biomarkers for clinical outcome following immunotherapy. We retrospectively studied the expression of immune (escape) markers in metastatic melanoma tissues of 27 patients before autologous tumor cell vaccination, and 16 patients who were intended to treat but were not vaccinated because of rapid disease progression. Immunohistochemical data of infiltrating (suppressive) cells, such as T cells, regulatory T cells, myeloid-derived suppressor cells, and mast cells, or the expression of T-cell inhibitory factors (PD-1/PD-L1, IDO, and galectins), cytotoxic molecules (granzyme-B), melanocyte differentiation antigens, HLA class-I and tolerogenic cytokines [interleukin (IL)-1, IL-6, IL-10, TNF-α, and TGF-ß] were correlated statistically to clinical outcome and overall survival (OS). Significantly more tumor-infiltrating CD4(+) and CD8(+) T cells (both P < 0.05) were found in nonprogressors to vaccination (n = 9; median OS, 56 months), compared with progressors (n = 18; median OS, 9.5 months). Moreover, granzyme-B expression was elevated in the tumors of nonprogressors, suggesting activated cytotoxic T cells or natural killer cells. T-cell infiltration and granzyme-B expression significantly correlated with overall OS. T-cell inhibitory factors and suppressive cells did not correlate with OS, suggesting minor influence of these immune-escape markers on clinical outcome. The data of progressors were comparable with those from patients with rapid progression (not vaccinated; n = 16; median OS, 3 months). Our study shows that high numbers of intratumoral activated CD4(+) or CD8(+) T cells, before autologous tumor cell vaccination, are associated with favorable clinical outcome. Analyses of these markers in the patients' tumor tissues before immunotherapy may therefore be a valuable tool to select patients for whom the treatment may result in potential clinical benefit.


Assuntos
Biomarcadores Tumorais/metabolismo , Imunoterapia/métodos , Melanoma/terapia , Neoplasias Cutâneas/terapia , Evasão Tumoral/imunologia , Adulto , Idoso , Vacinas Anticâncer/uso terapêutico , Feminino , GTP Fosfo-Hidrolases/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Masculino , Melanoma/genética , Melanoma/imunologia , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Resultado do Tratamento
8.
Oncoimmunology ; 3(9): e954862, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25941603

RESUMO

Immune escape mechanisms are prevalent in tumors, while their influence on the potency of antitumor immunotherapy has yet to be distinguished. We recently showed that increased numbers of intratumoral T cells rather than immune-escape-mechanisms significantly correlated with clinical outcome of advanced melanoma patients to subsequent autologous tumor cell vaccination. Our data emphasize the therapeutic relevance of tumor-infiltrating T cells for the clinical outcome.

9.
Pigment Cell Melanoma Res ; 25(1): 57-65, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21982055

RESUMO

In this study, we developed an in vivo vitiligo induction model to explore the underlying mechanisms leading to Koebner's phenomenon and to evaluate the efficacy of therapeutic strategies. The model consisted of 12 pigmented test regions on the back of generalized vitiligo patients that were exposed to three Koebner induction methods: cryotherapy, 755 nm laser therapy, and epidermal abrasion. In addition, four cream treatments (pimecrolimus, tacrolimus, steroid and placebo) were randomly applied. Koebnerization was efficiently induced by all three induction methods. In general, cryotherapy was the best method of Koebner induction, followed by 755 nm laser therapy and epidermal abrasion. Reproducible results were obtained, which showed enhanced depigmented surface areas and higher amounts of T lymphocytes in placebo-treated test zones compared to active treated areas. Tacrolimus and local steroids were better inhibitors of Koebner's process (P < 0.05) compared to pimecrolimus. Our in vivo vitiligo induction model is very informative to investigate vitiligo induction and to determine the efficacy of topical treatments in vitiligo. This proof of concept confirms the efficient comparison of head-to-head therapeutic strategies intra-individually in a standardized, specific and better timed way.


Assuntos
Crioterapia/efeitos adversos , Dermabrasão/efeitos adversos , Imunossupressores/uso terapêutico , Terapia com Luz de Baixa Intensidade/efeitos adversos , Vitiligo/tratamento farmacológico , Vitiligo/etiologia , Administração Cutânea , Adulto , Método Duplo-Cego , Feminino , Humanos , Imunossupressores/administração & dosagem , Células de Langerhans/patologia , Antígeno MART-1/análise , Masculino , Pessoa de Meia-Idade , Furoato de Mometasona , Pomadas , Pregnadienodiois/administração & dosagem , Pregnadienodiois/uso terapêutico , Reprodutibilidade dos Testes , Subpopulações de Linfócitos T/patologia , Tacrolimo/administração & dosagem , Tacrolimo/análogos & derivados , Tacrolimo/uso terapêutico , Triancinolona Acetonida/administração & dosagem , Triancinolona Acetonida/uso terapêutico , Vitiligo/imunologia , Vitiligo/patologia , Antígeno gp100 de Melanoma/análise
10.
Anticancer Res ; 31(11): 3697-703, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22110189

RESUMO

BACKGROUND/AIM: Regressing nevi are considered an example of an efficient early antitumoral response preventing the development of neoplasia. The underlying mechanism has not been elucidated, although an immune-based destruction of melanocytes is supposed. The aim of this study was to provide evidence of an effective immunosurveillance of pigment lesions in a patient at high risk of melanoma. CASE REPORT: A patient with the dysplastic nevus syndrome and a history of melanoma was included in this study. Since 2003, a marked regression of almost all nevi was observed. Immunohistochemistry was performed and the antigen specificity of T-cells was analyzed on T-cells isolated from a regressing nevus by flow cytometry using HLA-A2-peptide tetramers containing Mart-1(26-35), gp100(280-288), gp100(209-217) and tyrosinase(369-377). Immunohistochemistry of the regressing nevi showed a strong infiltrate of CD4 + and CD8 + T-cells. Flow cytometric analyses demonstrated the presence of a CD8 + T-cell response against gp100(280-288) and Mart-1(26-35) both in peripheral blood and in a regressing nevus. CONCLUSION: These findings indicate that an immune reaction against melanocyte differentiation antigens can target specifically nevi without signs of vitiligo and suggests that boosting the anti-melanocyte immune response in patients at high risk for melanoma may prevent tumor development at an early stage.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Síndrome do Nevo Displásico/imunologia , Antígeno HLA-A2/imunologia , Melanócitos/imunologia , Melanoma/genética , Melanoma/imunologia , Western Blotting , Síndrome do Nevo Displásico/patologia , Citometria de Fluxo , Humanos , Técnicas Imunoenzimáticas , Antígeno MART-1/imunologia , Masculino , Melanócitos/patologia , Melanoma/patologia , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/imunologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/imunologia , Vitiligo/imunologia , Vitiligo/patologia , Antígeno gp100 de Melanoma/imunologia
11.
Clin Cancer Res ; 17(17): 5736-47, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21750202

RESUMO

PURPOSE: To predict the potential antitumor effect of antigen-specific T cells in melanoma patients, we investigated T-cell effector function in relation to tumor-escape mechanisms. EXPERIMENTAL DESIGN: CD8(+) T cells isolated from tumor, adjacent normal skin, and peripheral blood of 17 HLA-A2(+) patients with advanced-stage melanoma were analyzed for their antigen specificity and effector function against melanocyte differentiation antigens MART-1, gp100, and tyrosinase by using HLA-A2/peptide tetramers and functional assays. In addition, the presence of tumor-escape mechanisms PD-L1/PD-1 pathway, FoxP3 and loss of HLA or melanocyte differentiation antigens, both required for tumor cell recognition and killing, were studied. RESULTS: Higher percentages of melanocyte antigen-specific CD8(+) T cells were found in the melanoma tissues as compared with adjacent normal skin and peripheral blood. Functional analysis revealed 2 important findings: (i) in 5 of 17 patients, we found cytokine production after specific peptide stimulation by tumor-infiltrating lymphocytes (TIL), not by autologous peripheral blood lymphocytes (PBL); (ii) CD8(+) T cells from 7 of 17 patients did not produce cytokines after specific stimulation, which corresponded with significant loss of tumor HLA-A2 expression. The presence of other tumor-escape mechanisms did not correlate to T-cell function. CONCLUSIONS: Our data show that functional T-cell responses could be missed when only PBL and not TIL are evaluated, emphasizing the importance of TIL analysis for immunomonitoring. Furthermore, loss of tumor HLA-A2 may explain the lack of T-cell functionality. These findings have important implications for selecting melanoma patients who may benefit from immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunoterapia , Linfócitos do Interstício Tumoral/imunologia , Melanoma/imunologia , Pele/imunologia , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-H1/biossíntese , Linfócitos T CD4-Positivos , Células Cultivadas , Citocinas/biossíntese , Citotoxicidade Imunológica , Feminino , Fatores de Transcrição Forkhead/biossíntese , Antígeno HLA-A2/biossíntese , Antígeno HLA-A2/imunologia , Humanos , Ativação Linfocitária , Antígeno MART-1/imunologia , Masculino , Melanoma/sangue , Melanoma/patologia , Melanoma/terapia , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/imunologia , Evasão Tumoral , Antígeno gp100 de Melanoma/imunologia
12.
Biochim Biophys Acta ; 1806(2): 208-19, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20655987

RESUMO

Hepatocyte growth factor (HGF) and its receptor MET are essential during embryonic development and throughout postnatal life. However, aberrant MET activation, due to overexpression, mutations, or autocrine ligand production, contributes to the development and progression of a variety of human cancers, often being associated with poor clinical outcome and drug resistance. B cell malignancies arise from B cells that are clonally expanded at different stages of differentiation. Despite major therapeutic advances, most mature B cell malignancies remain incurable and biologically-oriented therapeutic strategies are urgently needed. This review addresses the role of the HGF/MET pathway during B cell development and discusses how its aberrant activation contributes to the development of B cell lymphoproliferative disorders, with particular emphasis on multiple myeloma and diffuse large B cell lymphoma. These insights, combined with the recent development of clinical-grade agents targeting the MET pathway, provide the rationale to envision the HGF/MET pathway as a new promising target for the treatment of B cell malignancies.


Assuntos
Fator de Crescimento de Hepatócito/fisiologia , Linfoma de Células B/etiologia , Mieloma Múltiplo/etiologia , Proteínas Proto-Oncogênicas c-met/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Transdução de Sinais/fisiologia , Diferenciação Celular , Fator de Crescimento de Hepatócito/antagonistas & inibidores , Fator de Crescimento de Hepatócito/química , Humanos , Linfoma de Células B/tratamento farmacológico , Mieloma Múltiplo/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/química , Receptores de Fatores de Crescimento/antagonistas & inibidores , Receptores de Fatores de Crescimento/química
13.
PLoS One ; 5(5): e10626, 2010 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-20498710

RESUMO

BACKGROUND: Presently melanoma still lacks adequate treatment options for metastatic disease. While melanoma is exceptionally challenging to standard regimens, it is suited for treatment with immunotherapy based on its immunogenicity. Since treatment-related skin depigmentation is considered a favourable prognostic sign during melanoma intervention, we here aimed at the reverse approach of directly inducing vitiligo as a shortcut to effective anti-melanoma immunity. METHODOLOGY AND PRINCIPAL FINDINGS: We developed an effective and simple to use form of immunotherapy by combining the topical skin-bleaching agent monobenzone with immune-stimulatory imiquimod cream and cytosine-guanine oligodeoxynucleotides (CpG) injections (MIC therapy). This powerful new approach promptly induced a melanoma antigen-specific immune response, which abolished subcutaneous B16.F10 melanoma growth in up to 85% of C57BL/6 mice. Importantly, this regimen induced over 100 days of tumor-free survival in up to 60% of the mice, and forcefully suppressed tumor growth upon re-challenge either 65- or 165 days after MIC treatment cessation. CONCLUSIONS: MIC therapy is effective in eradicating melanoma, by vigilantly incorporating NK-, B- and T cells in its therapeutic effect. Based on these results, the MIC regimen presents a high-yield, low-cost and simple therapy, readily applicable in the clinic.


Assuntos
Aminoquinolinas/uso terapêutico , Fosfatos de Dinucleosídeos/uso terapêutico , Hidroquinonas/uso terapêutico , Imunoterapia , Melanoma/tratamento farmacológico , Pigmentação , Neoplasias Cutâneas/tratamento farmacológico , Adjuvantes Imunológicos/uso terapêutico , Aminoquinolinas/administração & dosagem , Aminoquinolinas/farmacologia , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Proliferação de Células/efeitos dos fármacos , Fosfatos de Dinucleosídeos/administração & dosagem , Fosfatos de Dinucleosídeos/farmacologia , Hidroquinonas/administração & dosagem , Hidroquinonas/farmacologia , Imiquimode , Imunoglobulina G/imunologia , Injeções Subcutâneas , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Contagem de Leucócitos , Ativação Linfocitária/efeitos dos fármacos , Depleção Linfocítica , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Pigmentação/efeitos dos fármacos , Neoplasias Cutâneas/imunologia
14.
Pigment Cell Melanoma Res ; 23(3): 375-84, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20370855

RESUMO

Segmental vitiligo is often ascribed to the neurogenic theory of melanocyte destruction, although data about the initial etiopathological events are scarce. Clinical, histopathological and T-cell phenotypic analyses were performed during the early onset of a segmental vitiligo lesion in a patient with associated halo nevi. Histopathological analysis revealed a lymphocytic infiltrate, mainly composed of CD8+ T-cells and some CD4(+) T-cells around the dermo-epidermal junction. Flow cytometry analysis of resident T-cells revealed a clear enrichment of pro-inflammatory IFN-gamma producing CD8+ T-cells in lesional skin compared to the non-lesional skin. Using human leukocyte antigen-peptide tetramers (MART-1, tyrosinase, gp100), increased numbers of T cells, recognizing melanocyte antigens were found in segmental vitiligo lesional skin, as compared with the non-lesional skin and the blood. Our findings indicate that a CD8+ melanocyte specific T cell-mediated immune response, as observed in generalized vitiligo, also plays a role in segmental vitiligo with associated halo nevi.


Assuntos
Imunofenotipagem , Nevo com Halo/imunologia , Nevo com Halo/patologia , Vitiligo/imunologia , Vitiligo/patologia , Antígenos/imunologia , Biópsia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Separação Celular , Humanos , Melanócitos/imunologia , Melanócitos/patologia , Nevo com Halo/sangue , Fenótipo , Pigmentação/imunologia , Pele/imunologia , Pele/patologia , Vitiligo/sangue
15.
Blood ; 107(2): 760-8, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16189274

RESUMO

Inappropriate activation of MET, the receptor tyrosine kinase for hepatocyte growth factor (HGF), has been implicated in tumorigenesis. Although we have previously shown that HGF/MET signaling controls survival and proliferation of multiple myeloma (MM), its role in the pathogenesis of other B-cell malignancies has remained largely unexplored. Here, we have examined a panel of 110 B-cell malignancies for MET expression, which, apart from MM (48%), was found to be largely confined to diffuse large B-cell lymphomas (DLBCLs) (30%). No amplification of the MET gene was found; however, mutational analysis revealed 2 germ-line missense mutations: R1166Q in the tyrosine kinase domain in 1 patient, and R988C in the juxtamembrane domain in 4 patients. The R988C mutation has recently been shown to enhance tumorigenesis. In MET-positive DLBCL cells, HGF induces MEK-dependent activation of ERK and PI3K-dependent phosphorylation of PKB, GSK3, and FOXO3a. Furthermore, HGF induces PI3K-dependent alpha4beta1 integrin-mediated adhesion to VCAM-1 and fibronectin. Within the tumor microenvironment of DLBCL, HGF is provided by macrophages, whereas DLBCL cells themselves produce the serine protease HGF activator (HGFA), which autocatalyzes HGF activation. Taken together, these data indicate that HGF/MET signaling, and secretion of HGFA by DLBCL cells, contributes to lymphomagenesis in DLBCL.


Assuntos
Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Linfoma de Células B/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Serina Endopeptidases/metabolismo , Transdução de Sinais , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Adesão Celular , Classe I de Fosfatidilinositol 3-Quinases , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Mutação em Linhagem Germinativa , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Hibridização In Situ , Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , MAP Quinase Quinase 1/metabolismo , Macrófagos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Mutação de Sentido Incorreto , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-met , Sondas RNA , RNA Mensageiro , Células Tumorais Cultivadas
16.
J Immunol ; 175(5): 2807-13, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16116166

RESUMO

Ag-specific B cell differentiation, the process that gives rise to plasma cells and memory B cells, involves the formation of germinal centers (GC). Within the GC microenvironment, multiple steps of B cell proliferation, selection, and maturation take place, which are controlled by the BCR in concert with cytokines and contact-dependent signals from follicular dendritic cells (FDCs) and T cells. Signaling by the multifunctional cytokine hepatocyte growth factor (HGF) and its receptor MET has been shown to induce integrin-mediated adhesion of B cells to VCAM-1, which is expressed by FDCs. In the present study we have examined the expression of regulatory components of the HGF/MET pathway, including HGF activator (HGFA), within the secondary lymphoid organ microenvironment. We show that MET is expressed by both centroblasts and plasma cells, and that HGFA is expressed by plasma cells. Because we have shown that HGF is a potent growth and survival factor for malignant plasma cells, HGF may also serve as a survival factor for normal plasma cells. Furthermore, we demonstrate that FDCs are the major source for HGF and its activator within the GC microenvironment. Both HGF and HGFA are expressed by FDCs in the GC dark zone (CD21high/CD23low), but not in the light zone (CD21high/CD23high). These findings suggest that HGF and HGFA provided by dark zone FDCs help to regulate the proliferation, survival, and/or adhesion of MET-positive centroblasts.


Assuntos
Células Dendríticas Foliculares/fisiologia , Centro Germinativo/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Serina Endopeptidases/metabolismo , Catálise , Criança , Humanos , Linfoma de Células B/etiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-met , Receptores de Fatores de Crescimento/fisiologia , Transdução de Sinais/fisiologia
17.
Blood ; 104(7): 2172-5, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15172968

RESUMO

Multiple myeloma (MM) is a common hematologic neoplasm consisting of malignant plasma cells, which expand in the bone marrow. A potential key signal in the evolution of MM is hepatocyte growth factor (HGF), which acts as a potent paracrine and/or autocrine growth factor and survival factor for MM cells. Proteolytic conversion of HGF into its active form is a critical limiting step in HGF/MET signaling. Here, we show that malignant MM plasma cells convert HGF into its active form and secrete HGF-activator (HGFA), a serine protease specific for HGF activation. By using serine protease inhibitors and neutralizing antibodies, we demonstrate that HGFA produced by the MM cells is responsible for their ability to catalyze HGF activation. We, therefore, suggest that autocatalyzation of HGF conversion by MM cells is an important step in HGF/MET-induced myeloma growth and survival, which may have implications for the management of this incurable form of cancer.


Assuntos
Fator de Crescimento de Hepatócito/metabolismo , Mieloma Múltiplo/metabolismo , Serina Endopeptidases/metabolismo , Idoso , Animais , Western Blotting , Células COS , Catálise , Linhagem Celular Tumoral , Separação Celular , Meios de Cultivo Condicionados/farmacologia , Ativação Enzimática , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Fígado/metabolismo , Masculino , Modelos Biológicos , Mieloma Múltiplo/patologia , Testes de Precipitina , Fatores de Tempo , Transfecção
18.
J Immunol ; 169(7): 3793-800, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12244174

RESUMO

Hepatocyte growth factor/scatter factor (HGF) and its receptor tyrosine kinase Met are key regulators of epithelial motility and morphogenesis. Recent studies indicate that the HGF/Met pathway also plays a role in B cell differentiation, whereas uncontrolled Met signaling may lead to B cell neoplasia. These observations prompted us to explore HGF/Met signaling in B cells. In this study, we demonstrate that HGF induces strong tyrosine phosphorylation of the proto-oncogene product c-Cbl in B cells and increases Cbl association with the Src family tyrosine kinases Fyn and Lyn, as well as with phosphatidylinositol-3 kinase and CrkL. In addition, we demonstrate that c-Cbl mediates HGF-induced ubiquitination of Met. This requires the juxtamembrane tyrosine Y1001 (Y2) of Met, but not the multifunctional docking site (Y14/15) or any additional C-terminal tyrosine residues (Y13-16). In contrast to wild-type c-Cbl, the transforming mutants v-Cbl and 70Z/3 Cbl, which lack the ubiquitin ligase RING finger domain, suppress Met ubiquitination. Our findings identify c-Cbl as a negative regulator of HGF/Met signaling in B cells, mediating ubiquitination and, consequently, proteosomal degradation of Met, and suggest a role for Cbl in Met-mediated tumorigenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Linfócitos B/metabolismo , Fator de Crescimento de Hepatócito/fisiologia , Proteínas Proto-Oncogênicas c-met/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais , Ubiquitinas/metabolismo , Animais , Linfócitos B/enzimologia , Células COS , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Humanos , Ligases/metabolismo , Proteínas Nucleares/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Fosfotirosina/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-cbl , Proteínas Proto-Oncogênicas c-fyn , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/imunologia , Especificidade por Substrato , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases , Quinases da Família src/metabolismo
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