RESUMO
BACKGROUND: Melanoma lacks validated blood-based biomarkers for monitoring and predicting treatment efficacy. Cell-free circulating tumour DNA (ctDNA) is a promising biomarker; however, various detection methods have been used, and, to date, no large studies have examined the association between serial changes in ctDNA and survival after BRAF, MEK, or BRAF plus MEK inhibitor therapy. We aimed to evaluate whether baseline ctDNA concentrations and kinetics could predict survival outcomes. METHODS: In this clinical validation study, we used analytically validated droplet digital PCR assays to measure BRAFV600-mutant ctDNA in pretreatment and on-treatment plasma samples from patients aged 18 years or older enrolled in two clinical trials. COMBI-d (NCT01584648) was a double-blind, randomised phase 3 study of dabrafenib plus trametinib versus dabrafenib plus placebo in previously untreated patients with BRAFV600 mutation-positive unresectable or metastatic melanoma. Patients had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. COMBI-MB (NCT02039947) was an open-label, non-randomised, phase 2 study evaluating dabrafenib plus trametinib in patients with BRAFV600 mutation-positive metastatic melanoma and brain metastases. Patients in cohort A of COMBI-MB had asymptomatic brain metastases, no previous local brain-directed therapy, and an ECOG performance status of 0 or 1. Biomarker analysis was a prespecified exploratory endpoint in both trials and performed in the intention-to-treat populations in COMBI-d and COMBI-MB. We investigated the association between mutant copy number (baseline or week 4 or zero conversion status) and efficacy endpoints (progression-free survival, overall survival, and best overall response). We used Cox models, Kaplan-Meier plots, and log-rank tests to explore the association of pretreatment ctDNA concentrations with progression-free survival and overall survival. The effect of additional prognostic variables such as lactate dehydrogenase was also investigated in addition to the mutant copy number. FINDINGS: In COMBI-d, pretreatment plasma samples were available from 345 (82%) of 423 patients and on-treatment (week 4) plasma samples were available from 224 (53%) of 423 patients. In cohort A of COMBI-MB, pretreatment and on-treatment samples were available from 38 (50%) of 76 patients with intracranial and extracranial metastatic melanoma. ctDNA was detected in pretreatment samples from 320 (93%) of 345 patients (COMBI-d) and 34 (89%) of 38 patients (COMBI-MB). When assessed as a continuous variable, elevated baseline BRAFV600 mutation-positive ctDNA concentration was associated with worse overall survival outcome (hazard ratio [HR] 1·13 [95% CI 1·09-1·18], p<0·0001 by univariate analysis), independent of treatment group and baseline lactate dehydrogenase concentrations (1·08 [1·03-1·13], p=0·0020), in COMBI-d. A ctDNA cutoff point of 64 copies per mL of plasma stratified patients enrolled in COMBI-d as high risk or low risk with respect to survival outcomes (HR 1·74 [95% CI 1·37-2·21], p<0·0001 for progression-free survival; 2·23 [1·73-2·87], p<0·0001 for overall survival) and was validated in the COMBI-MB cohort (3·20 [1·39-7·34], p=0·0047 for progression-free survival; 2·94 [1·18-7·32], p=0·016 for overall survival). In COMBI-d, undetectable ctDNA at week 4 was significantly associated with extended progression-free and overall survival, particularly in patients with elevated lactate dehydrogenase concentrations (HR 1·99 [95% CI 1·08-3·64], p=0·027 for progression-free survival; 2·38 [1·24-4·54], p=0·0089 for overall survival). INTERPRETATION: Pretreatment and on-treatment BRAFV600-mutant ctDNA measurements could serve as independent, predictive biomarkers of clinical outcome with targeted therapy. FUNDING: Novartis.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/secundário , DNA Tumoral Circulante/genética , Melanoma/patologia , Idoso , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , DNA Tumoral Circulante/análise , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Imidazóis/administração & dosagem , Masculino , Melanoma/tratamento farmacológico , Melanoma/genética , Pessoa de Meia-Idade , Oximas/administração & dosagem , Prognóstico , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Taxa de SobrevidaRESUMO
BACKGROUND: MoleMap NZ is a novel New Zealand-based store-and-forward telemedicine service to detect melanoma. It uses expert review of total body photography and close-up and dermoscopic images of skin lesions that are suspicious for malignancy. OBJECTIVE: The purpose of this study was to assess the effectiveness of MoleMap NZ as a melanoma early detection program. METHODS: We conducted a review of 2108 melanocytic lesions recommended for biopsy/excision by MoleMap NZ dermoscopists between January 2015 and December 2016. RESULTS: Pathologic diagnoses were available for 1571 lesions. Of these, 1303 (83%) lesions were benign and 260 (17%) lesions were diagnosed as melanoma, for a melanoma-specific benign:malignant ratio of 5.0:1. The number needed to biopsy to obtain 1 melanoma was 6. Among melanomas with available tumor thickness data (n = 137), 92% were <0.8 mm (range in situ to 3.1 mm), with in situ melanomas comprising 74%. LIMITATIONS: Only lesions recommended for excision were analyzed. Pathology results were available for 75% of these cases. Tumor thickness data were available for 53% of melanomas diagnosed. CONCLUSIONS: This real-world study of MoleMap NZ, a community-based teledermoscopy program, suggests that it has the potential to increase patients' access to specialist expertise via telemedicine. Additional studies are needed to more accurately define its efficacy.
Assuntos
Melanoma , Neoplasias Cutâneas , Telemedicina , Dermoscopia , Humanos , Melanoma/diagnóstico por imagem , Melanoma/epidemiologia , Nova ZelândiaRESUMO
Objectives. To determine the effect of new therapies and trends toward reduced mortality rates of melanoma.Methods. We reviewed melanoma incidence and mortality among Whites (the group most affected by melanoma) in 9 US Surveillance, Epidemiology, and End Results registry areas that recorded data between 1986 and 2016.Results. From 1986 to 2013, overall mortality rates increased by 7.5%. Beginning in 2011, the US Food and Drug Administration approved 10 new treatments for metastatic melanoma. From 2013 to 2016, overall mortality decreased by 17.9% (annual percent change [APC] = -6.2%; 95% confidence interval [CI] = -8.7%, -3.7%) with sharp declines among men aged 50 years or older (APC = -8.3%; 95% CI = -12.2%, -4.1%) starting in 2014. This recent, multiyear decline is the largest and most sustained improvement in melanoma mortality ever observed and is unprecedented in cancer medicine.Conclusions. The introduction of new therapies for metastatic melanoma was associated with a significant reduction in population-level mortality. Future research should focus on developing even more effective treatments, identifying biomarkers to select patients most likely to benefit, and renewing emphasis on public health approaches to reduce the number of patients with advanced disease.
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Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Fatores Etários , Idoso , Aprovação de Drogas/estatística & dados numéricos , Feminino , Humanos , Incidência , Masculino , Melanoma/tratamento farmacológico , Melanoma/mortalidade , Pessoa de Meia-Idade , Programa de SEER , Fatores Sexuais , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/mortalidade , Estados Unidos/epidemiologia , United States Food and Drug Administration , População Branca/estatística & dados numéricos , Melanoma Maligno CutâneoRESUMO
The growth of molecular technologies analyzing skin cells and inherited genetic variations has the potential to address current gaps in both diagnostic accuracy and prognostication in patients with melanoma or in individuals who are at risk for developing melanoma. In the second article in this continuing medical education series, novel molecular technologies are reviewed. These have been developed as adjunct tools for melanoma management and include the Pigmented Lesion Assay, myPath Melanoma, and DecisionDx-Melanoma tests, and genetic testing in patients with a strong familial melanoma history. These tests are commercially available and marketed as ancillary tools for clinical decision-making, diagnosis, and prognosis. We review fundamental principles behind each test, discuss peer-reviewed literature assessing their performance, and highlight the utility and limitations of each assay. The goal of this article is to provide a comprehensive, evidence-based foundation for clinicians regarding the management of patients with difficult pigmented lesions.
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Perfilação da Expressão Gênica , Testes Genéticos , Melanoma/diagnóstico , Melanoma/genética , Neoplasias Pancreáticas/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Antígenos de Neoplasias/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Perfilação da Expressão Gênica/métodos , Humanos , Técnicas de Diagnóstico Molecular , RNA Longo não Codificante/genéticaRESUMO
Managing the balance between accurately identifying early stage melanomas while avoiding obtaining biopsy specimens of benign lesions (ie, overbiopsy) is the major challenge of melanoma detection. Decision making can be especially difficult in patients with extensive atypical nevi. Recognizing that the primary screening modality for melanoma is subjective examination, studies have shown a tendency toward overbiopsy. Even low-risk routine surgical procedures are associated with morbidity, mounting health care costs, and patient anxiety. Recent advancements in noninvasive diagnostic modalities have helped improve diagnostic accuracy, especially when managing melanocytic lesions of uncertain diagnosis. Breakthroughs in artificial intelligence have also shown exciting potential in changing the landscape of melanoma detection. In the first article in this continuing medical education series, we review novel diagnostic technologies, such as automated 2- and 3-dimensional total body imaging with sequential digital dermoscopic imaging, reflectance confocal microscopy, and electrical impedance spectroscopy, and we explore the logistics and implications of potentially integrating artificial intelligence into existing melanoma management paradigms.
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Aprendizado de Máquina , Melanoma/diagnóstico por imagem , Fotografação/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Tecnologia Biomédica , Dermoscopia/métodos , Espectroscopia Dielétrica , Humanos , Imageamento Tridimensional , Microscopia Confocal/métodosRESUMO
BACKGROUND: Patients with thick primary melanomas (≥4 mm) have highly variable survival outcomes. Cell proliferation marker Ki-67 has been identified as promising biomarker in thick melanoma but has not been evaluated since the wide spread adoption of sentinel lymph node biopsy. We revisit its prognostic relevance in the sentinel node era. METHODS: We studied patients with thick (≥4 mm) primary melanoma prospectively enrolled in a clinicopathological biospecimen database from 2002 to 2015, and evaluated the prognostic value of Ki-67 expression while controlling for features included in the existing staging criteria. RESULTS: We analyzed 68 patients who underwent lymph node sampling and who had an available tumor for Ki-67 immunohistochemical (IHC) staining. The median tumor thickness was 6.0 mm; the median follow-up was 2.6 years. In multivariable analysis including nodal status and primary tumor ulceration, Ki-67 expression was an independent predictor of worse recurrence-free survival (HR 2.19, P = 0.024) and overall survival (HR 2.49, P = 0.028). Natural log-transformed tumor thickness (ln [thickness]) was also significantly associated with worse OS (HR 2.39, P = 0.010). CONCLUSION: We identify Ki-67 and ln (thickness) as potential biomarkers for patients with thick melanoma who have undergone nodal staging. If validated in additional studies, these biomarkers could be integrated into the staging criteria to improve risk-stratification.
Assuntos
Antígeno Ki-67/biossíntese , Linfonodos/patologia , Melanoma/metabolismo , Melanoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Biópsia de Linfonodo Sentinela , Taxa de SobrevidaRESUMO
INTRODUCTION: Biopsies of atypical melanocytic nevi are among the most commonly performed procedures by dermatologists. Margin assessment is often used to guide re-excision, but can be a point of confusion as negative margins reported in the planes of sections examined do not always reflect complete removal of a lesion. This study investigates the rates of false negative margins after both punch and shave biopsies. METHODS: We performed a retrospective analysis of 50 consecutive punch and shave biopsy specimens (1) diagnosed as DN, and (2) reported as having clear margins in the planes of section examined. Identified specimen blocks were then sectioned through to examine true margin involvement. RESULTS: Of the 50 specimens identified, 20% (n = 10) were found to have positive margins upon additional sectioning. We found no difference between the groups with respect to biopsy technique, type of nevus, degree of atypia, or gender. CONCLUSION: This study observed false negative peripheral margin status in a sizeable proportion of biopsy specimens, which did not vary significantly based on biopsy technique or pathologic characteristics. This finding reflects a limitation of standard tissue processing, in which a limited proportion of the true margin is evaluated, and may be of note to many dermatologists who base their decision to re-excise on the reporting of margin involvement. J Drugs Dermatol. 2018;17(7):810-812.
Assuntos
Síndrome do Nevo Displásico/patologia , Margens de Excisão , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Adulto , Biópsia/efeitos adversos , Biópsia/métodos , Biópsia/normas , Tomada de Decisão Clínica , Síndrome do Nevo Displásico/cirurgia , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nevo Pigmentado/cirurgia , Estudos Retrospectivos , Fatores Sexuais , Pele/patologia , Neoplasias Cutâneas/cirurgia , Adulto JovemRESUMO
OBJECTIVES: Since 2011, metastatic melanoma treatment has evolved with commercial approval of BRAF- and MEK-targeted therapy and CTLA-4- and PD-1-blocking antibodies (immune checkpoint inhibitors, ICI). While novel therapies have demonstrated improved prognosis in clinical trials, few studies have examined the evolution of prognosis and toxicity of these drugs among an unselected population. We assess whether survival and toxicity reported in trials, which typically exclude most patients with brain metastases and poor performance status, are recapitulated within a commercial access population. METHODS: 182 patients diagnosed with stage IV melanoma from July 2006 to December 2013 and treated with BRAF- and/or MEK-targeted therapy or ICI were prospectively studied. Outcomes and clinicopathologic differences between trial and commercial cohorts were assessed. RESULTS: Patients receiving commercial therapy (vs. on trial) had poorer prognostic features (i.e., brain metastases) and lower median overall survival (mOS) when assessed across all treatments (9.2 vs. 17.5 months, p = 0.0027). While toxicity within trial and commercial cohorts did not differ, patients who experienced toxicity had increased mOS (p < 0.001), irrespective of stratification by trial status or therapy. CONCLUSION: Metastatic melanoma patients receiving commercial treatment may represent a different clinical population with poor prognostic features compared to trial patients. Toxicity may prognosticate treatment benefit.
Assuntos
Antineoplásicos/uso terapêutico , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/efeitos adversos , Terapia de Alvo Molecular/métodos , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Padrão de Cuidado , Anticorpos Monoclonais/uso terapêutico , Ensaios Clínicos Fase III como Assunto , Feminino , Humanos , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxa de Sobrevida , Resultado do TratamentoRESUMO
BACKGROUND: Clinical and histopathologic assessment of pigmented skin lesions remains challenging even for experts. Differentiated and accurate noninvasive diagnostic modalities are highly desirable. OBJECTIVE: We sought to provide clinicians with such a tool. METHODS: A 2-gene classification method based on LINC00518 and preferentially expressed antigen in melanoma (PRAME) gene expression was evaluated and validated in 555 pigmented lesions (157 training and 398 validation samples) obtained noninvasively via adhesive patch biopsy. Results were compared with standard histopathologic assessment in lesions with a consensus diagnosis among 3 experienced dermatopathologists. RESULTS: In 398 validation samples (87 melanomas and 311 nonmelanomas), LINC00518 and/or PRAME detection appropriately differentiated melanoma from nonmelanoma samples with a sensitivity of 91% and a specificity of 69%. We established LINC00518 and PRAME in both adhesive patch melanoma samples and underlying formalin fixed paraffin embedded (FFPE) samples of surgically excised primary melanomas and in melanoma lymph node metastases. LIMITATIONS: This technology cannot be used on mucous membranes, palms of hands, and soles of feet. CONCLUSIONS: This noninvasive 2-gene pigmented lesion assay classifies pigmented lesions into melanoma and nonmelanoma groups and may serve as a tool to help with diagnostic challenges that may be inherently linked to the visual image and pattern recognition approach.
Assuntos
Antígenos de Neoplasias/genética , Expressão Gênica , Melanoma/genética , Nevo Pigmentado/genética , RNA Longo não Codificante/genética , RNA Neoplásico/análise , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/métodos , Feminino , Humanos , Metástase Linfática , Masculino , Melanoma/diagnóstico , Melanoma/secundário , Pessoa de Meia-Idade , Nevo Pigmentado/diagnóstico , Nevo Pigmentado/patologia , Sensibilidade e Especificidade , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Adulto JovemRESUMO
BACKGROUND: Complete removal of individual dysplastic nevi (DN) is often accomplished by a second surgical procedure after the initial biopsy. The choice to perform the second procedure is strongly influenced by histopathologic margin status of the initial biopsy specimen. OBJECTIVE: To evaluate the clinical and histopathologic outcomes of in toto biopsy of DN using a predetermined margin of normal skin. METHODS: We conducted a prospective study of a saucerization method using a defined 2-mm margin in patients undergoing biopsy of a pigmented skin lesion. RESULTS: We performed 151 biopsies in 138 patients. Overall, 137 of 151 lesions subjected to biopsy (90.7%) were melanocytic: 86 DN (57.0%), 40 nevi without atypia (26.5%), and 11 melanomas (7.3%). Of 78 DN, 68 (87.2%) were removed with clear histopathologic margins (8 DN were excluded because of inadequate processing). There was no clinical evidence of recurrence at any of the biopsy sites that were simply observed (i.e., not re-excised) over a median of 16.9 months. LIMITATIONS: There were few biopsies performed on the face. CONCLUSIONS: The complete histopathologic removal of nearly 9 of 10 DN using a peripheral margin of 2 mm of normal skin and a depth at the dermis and subcutaneous fat junction has the potential to decrease second procedures at DN biopsy sites, thereby decreasing patient morbidity and saving health care dollars.
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Síndrome do Nevo Displásico/patologia , Síndrome do Nevo Displásico/cirurgia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto JovemRESUMO
OBJECTIVES: The impact of ethnicity and the socioeconomic status (SES) among Caucasians is not well studied. Here, we examine the impact of income on melanoma presentation and prognosis within a Caucasian cohort, accounting for ethnicity, as some reports suggest increased melanoma incidence in Ashkenazi Jewish (AJ) BRCA mutation carriers. METHODS: We studied prospectively enrolled primary melanoma patients at New York University. SES data were estimated using United States' Census Bureau data and patient zip codes. We evaluated associations between ethnicity, SES, and baseline characteristics using the χ² test and multivariate logistic regression. We compared survival distributions using Kaplan-Meier curves, log-rank tests, and Cox proportional hazard ratios. RESULTS: Of the 1,339 enrolled patients, AJ represented 32% (n = 423). Apart from AJ being older at presentation (p < 0.001), no significant differences were observed in baseline characteristics between ethnic groups. Patients with a median household income (MHI) lower than the median of the cohort were significantly more likely to present with advanced stages (p < 0.001) compared to patients with a higher MHI. Shorter overall (p = 0.016) and post-recurrence survival (p = 0.042) was also observed in patients from lower-income households. CONCLUSION: Data suggest that disparities in melanoma presentation in Caucasians stratify according to income independent of ethnic background.
Assuntos
Renda/estatística & dados numéricos , Judeus/estatística & dados numéricos , Melanoma/etnologia , Melanoma/patologia , Recidiva Local de Neoplasia/mortalidade , Neoplasias Cutâneas/etnologia , Neoplasias Cutâneas/patologia , População Branca/etnologia , Adulto , Idoso , Diagnóstico Tardio/estatística & dados numéricos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cidade de Nova Iorque/epidemiologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Neoplasias Cutâneas/mortalidade , Taxa de SobrevidaAssuntos
Sarda Melanótica de Hutchinson/diagnóstico por imagem , Sarda Melanótica de Hutchinson/cirurgia , Margens de Excisão , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/cirurgia , Humanos , Sarda Melanótica de Hutchinson/patologia , Microscopia Confocal , Neoplasias Cutâneas/patologiaRESUMO
BACKGROUND: Acral lentiginous melanoma has increased mortality compared with other melanoma subtypes and disproportionately affects ethnic minorities. Acral melanocytic lesions have not been well studied in diverse populations of the United States. OBJECTIVE: We sought to assess the prevalence, awareness, and dermoscopic patterns of acral melanocytic lesions in skin-of-color and non-Hispanic white patients. METHODS: We prospectively examined the palms and soles of 1052 patients presenting to dermatology clinics in New York, NY, and Miami, FL, from October 2013 to April 2015. RESULTS: Acral melanocytic lesions were observed in 36% of our cohort. Skin-of-color patients were more likely to have acral melanocytic lesions than non-Hispanic white patients (P < .01). Acral melanocytic lesions correlated with increased mole counts, particularly on non-Hispanic white patients. The majority of lesions demonstrated benign dermoscopic patterns. We observed 2 lesions with the parallel ridge pattern in our cohort, both found to be atypical nevi on biopsy specimen. Patients often lacked awareness of the presence of their lesions. LIMITATIONS: Interobserver variability in assessing dermoscopic patterns is a limitation. CONCLUSIONS: Melanocytic lesions of the palms and soles are common, particularly in a cohort of multiple ethnicities from the United States. Dermoscopy of acral lesions is an important clinical tool for diagnosis and management of these lesions.
Assuntos
Dermoscopia/métodos , Melanoma/diagnóstico , Nevo Pigmentado/diagnóstico , Neoplasias Cutâneas/diagnóstico , Pigmentação da Pele/fisiologia , População Branca/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Conscientização , Biópsia por Agulha , Estudos de Coortes , Feminino , Florida/epidemiologia , Humanos , Imuno-Histoquímica , Masculino , Melanoma/etnologia , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Nevo Pigmentado/etnologia , Variações Dependentes do Observador , Prevalência , Estudos Prospectivos , Medição de Risco , Neoplasias Cutâneas/etnologia , Estados Unidos/epidemiologiaRESUMO
Cancer is a disease consisting of both genetic and epigenetic changes. Although increasing evidence demonstrates that tumour progression entails chromatin-mediated changes such as DNA methylation, the role of histone variants in cancer initiation and progression currently remains unclear. Histone variants replace conventional histones within the nucleosome and confer unique biological functions to chromatin. Here we report that the histone variant macroH2A (mH2A) suppresses tumour progression of malignant melanoma. Loss of mH2A isoforms, histone variants generally associated with condensed chromatin and fine-tuning of developmental gene expression programs, is positively correlated with increasing malignant phenotype of melanoma cells in culture and human tissue samples. Knockdown of mH2A isoforms in melanoma cells of low malignancy results in significantly increased proliferation and migration in vitro and growth and metastasis in vivo. Restored expression of mH2A isoforms rescues these malignant phenotypes in vitro and in vivo. We demonstrate that the tumour-promoting function of mH2A loss is mediated, at least in part, through direct transcriptional upregulation of CDK8. Suppression of CDK8, a colorectal cancer oncogene, inhibits proliferation of melanoma cells, and knockdown of CDK8 in cells depleted of mH2A suppresses the proliferative advantage induced by mH2A loss. Moreover, a significant inverse correlation between mH2A and CDK8 expression levels exists in melanoma patient samples. Taken together, our results demonstrate that mH2A is a critical component of chromatin that suppresses the development of malignant melanoma, a highly intractable cutaneous neoplasm.
Assuntos
Quinase 8 Dependente de Ciclina/metabolismo , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Melanoma/patologia , Metástase Neoplásica/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HCT116 , Histonas/deficiência , Histonas/genética , Humanos , Melanoma/fisiopatologia , Melanoma Experimental , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Metástase Neoplásica/fisiopatologia , Ratos , Regulação para CimaRESUMO
BACKGROUND: Due to high melanoma immunogenicity, germline genetic variants in immune pathways have been studied for association with melanoma prognosis. However, limited candidate selection, inadequate power, or lack of independent validation have hampered the reproducibility of these prior findings, preventing personalised clinical applicability in melanoma prognostication. Our objective was to assess the prognostic utility of genetic variants in immunomodulatory pathways for prediction of melanoma clinical outcomes. METHODS: We genotyped 72 tag single nucleotide polymorphisms (SNPs) in 44 immunomodulatory genes in a population sample of 1022 melanoma patients and performed Cox regression analysis to test the association between SNPs and melanoma recurrence-free (RFS) and overall survival (OS). We have further investigated the most significant associations using a fine mapping strategy and followed with functional analyses in CD4+ T cells in a subset of 75 melanoma patients. RESULTS: The most significant associations were found with melanoma OS for rs3024493 in IL10 at chromosome 1q32.1 (heterozygous HR 0.58, 95% CI 0.39 to 0.86; p=0.0006), a variant previously shown to be linked with autoimmune conditions. Multiple additional SNPs at 1q32.1 were also nominally associated with OS confirming at least two independent association signals in this locus. In addition, we found rs3024493 associated with the downregulation of interleukin 10 (IL10) secretion in CD4+ T cells. CONCLUSIONS: We discovered novel associations of IL10 with melanoma survival at 1q32.1, suggesting this locus should be considered as a novel melanoma prognostic biomarker with potential for aiding melanoma patient management. Our findings also provide further support for an alternative role of IL10 in stimulation of anti-tumour immune response.