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1.
Nat Commun ; 11(1): 5084, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033253

RESUMO

Identifying factors underlying resistance to immune checkpoint therapy (ICT) is still challenging. Most cancer patients do not respond to ICT and the availability of the predictive biomarkers is limited. Here, we re-analyze a publicly available single-cell RNA sequencing (scRNA-seq) dataset of melanoma samples of patients subjected to ICT and identify a subset of macrophages overexpressing TREM2 and a subset of gammadelta T cells that are both overrepresented in the non-responding tumors. In addition, the percentage of a B cell subset is significantly lower in the non-responders. The presence of these immune cell subtypes is corroborated in other publicly available scRNA-seq datasets. The analyses of bulk RNA-seq datasets of the melanoma samples identify and validate a signature - ImmuneCells.Sig - enriched with the genes characteristic of the above immune cell subsets to predict response to immunotherapy. ImmuneCells.Sig could represent a valuable tool for clinical decision making in patients receiving immunotherapy.


Assuntos
Perfilação da Expressão Gênica , Imunoterapia , Macrófagos/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores Imunológicos/metabolismo , Linfócitos T/metabolismo , Área Sob a Curva , Linfócitos B/metabolismo , Biomarcadores Tumorais/metabolismo , Humanos , Macrófagos/patologia , Melanoma/genética , Melanoma/patologia , Reprodutibilidade dos Testes
2.
N Engl J Med ; 383(12): 1139-1148, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32877599

RESUMO

BACKGROUND: In the previously reported primary analysis of this phase 3 trial, 12 months of adjuvant dabrafenib plus trametinib resulted in significantly longer relapse-free survival than placebo in patients with resected stage III melanoma with BRAF V600E or V600K mutations. To confirm the stability of the relapse-free survival benefit, longer-term data were needed. METHODS: We randomly assigned 870 patients who had resected stage III melanoma with BRAF V600E or V600K mutations to receive 12 months of oral dabrafenib (at a dose of 150 mg twice daily) plus trametinib (2 mg once daily) or two matched placebos. The primary end point was relapse-free survival. Here, we report 5-year results for relapse-free survival and survival without distant metastasis as the site of the first relapse. Overall survival was not analyzed, since the required number of events to trigger the final overall survival analysis had not been reached. RESULTS: The minimum duration of follow-up was 59 months (median patient follow-up, 60 months for dabrafenib plus trametinib and 58 months for placebo). At 5 years, the percentage of patients who were alive without relapse was 52% (95% confidence interval [CI], 48 to 58) with dabrafenib plus trametinib and 36% (95% CI, 32 to 41) with placebo (hazard ratio for relapse or death, 0.51; 95% CI, 0.42 to 0.61). The percentage of patients who were alive without distant metastasis was 65% (95% CI, 61 to 71) with dabrafenib plus trametinib and 54% (95% CI, 49 to 60) with placebo (hazard ratio for distant metastasis or death, 0.55; 95% CI, 0.44 to 0.70). No clinically meaningful between-group difference in the incidence or severity of serious adverse events was reported during the follow-up period. CONCLUSIONS: In the 5-year follow-up of a phase 3 trial involving patients who had resected stage III melanoma with BRAF V600E or V600K mutations, 12 months of adjuvant therapy with dabrafenib plus trametinib resulted in a longer duration of survival without relapse or distant metastasis than placebo with no apparent long-term toxic effects. (Funded by GlaxoSmithKline and Novartis; COMBI-AD ClinicalTrials.gov number, NCT01682083; EudraCT number, 2012-001266-15.).


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Imidazóis/uso terapêutico , Melanoma/tratamento farmacológico , Oximas/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Administração Oral , Adulto , Idoso , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/genética , Análise de Sobrevida
3.
Mutat Res ; 785: 108321, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32800272

RESUMO

BRAF is a member of the RAF family of serine/threonine-specific protein kinases. Oncogenic BRAF, in particular, BRAF V600E, can disturb the normal protein folding machinery in the endoplasmic reticulum (ER) leading to accumulation of unfolded/misfolded proteins in the ER lumen, a condition known as endoplasmic reticulum (ER) stress. To alleviate such conditions, ER-stressed cells have developed a highly robust and adaptable signaling network known as unfolded protein response (UPR). UPR is ordinarily a cytoprotective response and usually operates through the induction of autophagy, an intracellular lysosomal degradation pathway that directs damaged proteins, protein aggregates, and damaged organelles for bulk degradation and recycling. Both ER stress and autophagy are involved in the progression and chemoresistance of melanoma. Melanoma, which arises as a result of malignant transformation of melanocytes, exhibits exceptionally high therapeutic resistance. Many mechanisms of therapeutic resistance have been identified in individual melanoma patients and in preclinical BRAF-driven melanoma models. Recently, it has been recognized that oncogenic BRAF interacts with GRP78 and removes its inhibitory influence on the three fundamental ER stress sensors of UPR, PERK, IRE1α, and ATF6. Dissociation of GRP78 from these ER stress sensors prompts UPR that subsequently activates cytoprotective autophagy. Thus, pharmacological inhibition of BRAF-induced ER stress-mediated autophagy can potentially resensitize BRAF mutant melanoma tumors to apoptosis. However, the underlying molecular mechanism of how oncogenic BRAF elevates the basal level of ER stress-mediated autophagy in melanoma tumors is not well characterized. A better understanding of the crosstalk between oncogenic BRAF, ER stress and autophagy may provide a rationale for improving existing cancer therapies and identify novel targets for therapeutic intervention of melanoma.


Assuntos
Autofagia , Resistencia a Medicamentos Antineoplásicos , Estresse do Retículo Endoplasmático , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Resposta a Proteínas não Dobradas , Apoptose , Humanos , Melanoma/tratamento farmacológico , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico
4.
Nat Commun ; 11(1): 3800, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32733040

RESUMO

Frameshift insertion/deletions (fs-indels) are an infrequent but highly immunogenic mutation subtype. Although fs-indels are degraded through the nonsense-mediated decay (NMD) pathway, we hypothesise that some fs-indels escape degradation and elicit anti-tumor immune responses. Using allele-specific expression analysis, expressed fs-indels are enriched in genomic positions predicted to escape NMD, and associated with higher protein expression, consistent with degradation escape (NMD-escape). Across four independent melanoma cohorts, NMD-escape mutations are significantly associated with clinical-benefit to checkpoint inhibitor (CPI) therapy (Pmeta = 0.0039). NMD-escape mutations are additionally found to associate with clinical-benefit in the low-TMB setting. Furthermore, in an adoptive cell therapy treated melanoma cohort, NMD-escape mutation count is the most significant biomarker associated with clinical-benefit. Analysis of functional T cell reactivity screens from personalized vaccine studies shows direct evidence of fs-indel derived neoantigens eliciting immune response, particularly those with highly elongated neo open reading frames. NMD-escape fs-indels represent an attractive target for biomarker optimisation and immunotherapy design.


Assuntos
Melanoma/genética , Melanoma/imunologia , Degradação do RNAm Mediada por Códon sem Sentido/genética , Linfócitos T/imunologia , Evasão Tumoral/genética , Transferência Adotiva , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/genética , Mutação da Fase de Leitura/genética , Humanos , Mutação INDEL/genética , Imunoterapia Adotiva , Linfócitos T/transplante , Sequenciamento Completo do Exoma
5.
Nat Commun ; 11(1): 3946, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770055

RESUMO

Melanomas can switch to a dedifferentiated cell state upon exposure to cytotoxic T cells. However, it is unclear whether such tumor cells pre-exist in patients and whether they can be resensitized to immunotherapy. Here, we chronically expose (patient-derived) melanoma cell lines to differentiation antigen-specific cytotoxic T cells and observe strong enrichment of a pre-existing NGFRhi population. These fractions are refractory also to T cells recognizing non-differentiation antigens, as well as to BRAF + MEK inhibitors. NGFRhi cells induce the neurotrophic factor BDNF, which contributes to T cell resistance, as does NGFR. In melanoma patients, a tumor-intrinsic NGFR signature predicts anti-PD-1 therapy resistance, and NGFRhi tumor fractions are associated with immune exclusion. Lastly, pharmacologic NGFR inhibition restores tumor sensitivity to T cell attack in vitro and in melanoma xenografts. These findings demonstrate the existence of a stable and pre-existing NGFRhi multitherapy-refractory melanoma subpopulation, which ought to be eliminated to revert intrinsic resistance to immunotherapeutic intervention.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Melanoma/tratamento farmacológico , Proteínas do Tecido Nervoso/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores de Fator de Crescimento Neural/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Linfócitos T Citotóxicos/imunologia , Animais , Antineoplásicos Imunológicos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/antagonistas & inibidores , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Masculino , Melanoma/genética , Melanoma/imunologia , Melanoma/patologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , RNA-Seq , Receptores de Fator de Crescimento Neural/antagonistas & inibidores , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Linfócitos T Citotóxicos/metabolismo , Evasão Tumoral/genética , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Nat Commun ; 11(1): 4306, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855398

RESUMO

Metastatic melanoma carries a poor prognosis despite modern systemic therapies. Understanding the evolution of the disease could help inform patient management. Through whole-genome sequencing of 13 melanoma metastases sampled at autopsy from a treatment naïve patient and by leveraging the analytical power of multi-sample analyses, we reveal evidence of diversification among metastatic lineages. UV-induced mutations dominate the trunk, whereas APOBEC-associated mutations are found in the branches of the evolutionary tree. Multi-sample analyses from a further seven patients confirmed that lineage diversification was pervasive, representing an important mode of melanoma dissemination. Our analyses demonstrate that joint analysis of cancer cell fraction estimates across multiple metastases can uncover previously unrecognised levels of tumour heterogeneity and highlight the limitations of inferring heterogeneity from a single biopsy.


Assuntos
Evolução Clonal , Heterogeneidade Genética , Melanoma/genética , Neoplasias Cutâneas/genética , Idoso , Biópsia , Análise Mutacional de DNA , Humanos , Masculino , Melanoma/secundário , Estudos Prospectivos , Pele/patologia , Neoplasias Cutâneas/patologia , Sequenciamento Completo do Genoma
7.
Value Health ; 23(7): 898-906, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32762992

RESUMO

OBJECTIVES: We evaluated how next generation sequencing (NGS) can modify care pathways in an observational impact study in France. METHODS: All patients with lung cancer, colorectal cancer, or melanoma who had NGS analyses of somatic genomic alterations done in 1 of 7 biomolecular platforms certified by the French National Cancer Institute (INCa) between 2013 and 2016 were eligible. We compared patients' pathways before and after their NGS results. Endpoints consisted of the turnaround time in obtaining results, the number of patients with at least 1 genomic alteration identified, the number of actionable alterations, the impact of the genomic multidisciplinary tumor board on care pathways, the number of changes in the treatment plan, and the survival outcome up to 1 year after NGS analyses. RESULTS: 1213 patients with a request for NGS analysis were included. NGS was performed for 1155 patients, identified at least 1 genomic alteration for 867 (75%), and provided an actionable alteration for 614 (53%). Turnaround time between analyses and results was on average 8 days (Min: 0; Max: 95) for all cancer types. Before NGS analysis, 33 of 614 patients (5%) were prescribed a targeted therapy compared with 54 of 614 patients (8%) after NGS analysis. Proposition of inclusion in clinical trials with experimental treatments increased from 5% (n = 31 of 614) before to 28% (n = 178 of 614) after NGS analysis. Patients who benefited from a genotype matched treatment after NGS analysis tended to have a better survival outcome at 1 year than patients with nonmatched treatment: 258 days (±107) compared with 234 days (±106), (P = .41). CONCLUSIONS: NGS analyses resulted in a change in patients' care pathways for 20% of patients (n = 232 of 1155).


Assuntos
Neoplasias Colorretais/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Melanoma/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/terapia , Feminino , França , Genômica/métodos , Acesso aos Serviços de Saúde , Humanos , Neoplasias Pulmonares/terapia , Masculino , Melanoma/terapia , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estudos Retrospectivos , Sobrevida , Fatores de Tempo , Adulto Jovem
8.
Zhonghua Bing Li Xue Za Zhi ; 49(8): 827-833, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-32746551

RESUMO

Objective: To investigate the clinical value of the first multicolor fluorescence in situ hybridization (FISH) assay on multiple genes, and combined with 9p21 and 8q24 evaluation in the differential diagnosis of melanoma. Methods: Fifty-six melanomas and 36 benign melanocytic nevi diagnosed in Fudan University Shanghai Cancer Center from 2017 to 2019 were included. Each specimen was examined by first multicolor FISH assay targeting 6p25 (RREB1), 6q23 (MYB), 11q13 (CCND1) and CEP6, as well as 9p21 (CDKN2A) and 8q24 (MYC). The results of FISH assay in all cases were recorded according to Gerami's criteria. Basing on the sensitivity and specificity of the first FISH assay, the refinement of diagnosis by adding combined 9p21 and 8q24 probes was further evaluated, as well as their association with different clinicopathological features. Results: In 86 cases, the FISH signals were adequate for analysis. Of the 56 melanoma cases, 52 cases were adequate for analysis; 36 cases (69.2%) were positive in the first FISH assay. The most frequent chromosomal anomaly was gain of RREB1 (30/52, 57.7%), followed by gain of CCND1 (20/52, 38.5%), loss of MYB relative to CEP6 (18/52, 34.6%) and gain of RREB1 relative to CEP6 (17/52, 32.7%). The frequency of homozygous deletions in 9p21 was 15.4% (8/52) and gain of 8q24 was 36.5% (19/52). Among the 36 melanocytic nevi cases, FISH results could be accurately evaluated in 34 cases, and none showed a positive result in the first FISH assay or 9p21 and 8q24 FISH analysis. Compared with the first FISH assay, the sensitivity of combination with 9p21 and 8q24 FISH analysis increased from 69.2% to 76.9% (40/52) and the specificity remained 100.0%. Statistical data showed that the rates of FISH positivity in patients with acral-lentiginious melanoma and nodual melanoma subtypes were higher than that in patients with superficial spreading melanoma and lentigo maligna melanoma subtypes, and patients with Breslow thickness>2.0 mm had higher positive FISH frequency than patients with Breslow thickness ≤2.0 mm. Conclusion: Multisite FISH analysis is a highly effective ancillary tool for the differentiation of unequivocal malignant from benign melanocytic lesions. By combining the first FISH assay with CDKN2A and MYC assay, the clinical utility of FISH analysis is further optimized in differential diagnosis of melanoma. Patients with Breslow thickness>2.0 mm, or acral-lentiginious melanoma and nodual melanoma subtypes tend to have higher FISH positivity. There remains a need to further explore the ancillary value of FISH analysis in diagnosis of ambiguous lesions.


Assuntos
Melanoma/diagnóstico , Melanoma/genética , Nevo Pigmentado , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , China , Diagnóstico Diferencial , Humanos , Hibridização in Situ Fluorescente
9.
Yonsei Med J ; 61(7): 562-571, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32608199

RESUMO

Melanoma, originating from epidermal melanocytes, is a heterogeneous disease that has the highest mortality rate among all types of skin cancers. Numerous studies have revealed the cause of this cancer as related to various somatic driver mutations, including alterations in KIT-a proto-oncogene encoding for a transmembrane receptor tyrosine kinase. Although accounting for only 3% of all melanomas, mutations in c-KIT are mostly derived from acral, mucosal, and chronically sun-damaged melanomas. As an important factor for cell differentiation, proliferation, and survival, inhibition of c-KIT has been exploited for clinical trials in advanced melanoma. Here, apart from the molecular background of c-KIT and its cellular functions, we will review the wide distribution of alterations in KIT with a catalogue of more than 40 mutations reported in various articles and case studies. Additionally, we will summarize the association of KIT mutations with clinicopathologic features (age, sex, melanoma subtypes, anatomic location, etc.), and the differences of mutation rate among subgroups. Finally, several therapeutic trials of c-KIT inhibitors, including imatinib, dasatinib, nilotinib, and sunitinib, will be analyzed for their success rates and limitations in advanced melanoma treatment. These not only emphasize c-KIT as an attractive target for personalized melanoma therapy but also propose the requirement for additional investigational studies to develop novel therapeutic trials co-targeting c-KIT and other cytokines such as members of signaling pathways and immune systems.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Proteínas Proto-Oncogênicas c-kit/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo , Feminino , Humanos , Masculino , Melanoma/genética , Membrana Mucosa/metabolismo , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptores Proteína Tirosina Quinases/genética , Neoplasias Cutâneas/genética
10.
Anticancer Res ; 40(7): 3839-3846, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620623

RESUMO

BACKGROUND/AIM: Because 50% of uveal melanoma metastasize within 10 years of diagnosis, there is urgent need for accurate prognostic factors. MATERIALS AND METHODS: To identify genes that can act as prognostic factors in uveal melanoma, we performed survival analyses using three independent cohorts. Using log-rank test and univariate cox regression, genes which could stratify the prognosis in all cohorts simultaneously depending on their expression levels were selected as novel biomarkers. Hub genes were obtained by analyzing the interaction and relationship between the selected genes using String and Cytoscape. Additionally, prognostic power was calculated by using C-indices and AUC. RESULTS: A total of 37 oncogene-like and 14 tumor suppressor-like genes were selected. Protein-protein analysis revealed that NDUFB9, NDUFV2, CYC1 among oncogene-like genes, CTNNB1 among tumor suppressor-like genes were found to be hub genes and core biomarkers in uveal melanoma. CONCLUSION: NDUFB9, NDUFV2, CYC1 and CTNNB1 genes may act as prognostic factors in uveal melanoma.


Assuntos
Biomarcadores Tumorais/genética , Melanoma/genética , Neoplasias Uveais/genética , Estudos de Coortes , Biologia Computacional/métodos , Bases de Dados Genéticas , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Oncogenes , Prognóstico , Mapas de Interação de Proteínas , Transcriptoma , Neoplasias Uveais/mortalidade
11.
Cancer Treat Rev ; 88: 102060, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32619863

RESUMO

Phenotypic plasticity of malignant melanoma is a well-known phenomenon. Several translational studies and small case series have reported this clinical and biological entity, particularly in metastatic melanoma, showing frequent aberrant expression of non-melanocytic differentiation markers of different lineages, posing remarkable challenges due to several alternative differential diagnoses including undifferentiated carcinoma and sarcomas. When melanoma loses its typical morpho-phenotype by routinely used diagnostic immunohistochemical markers, it is defined as "dedifferentiated melanoma". Historically, this process was closely related to diagnostic interpretative difficulties. In recent years, however, dedifferentiation has been increasingly recognized as an important biological phenomenon that demonstrates the phenotypic and genetic plasticity of melanoma, and specifically the non-irreversibility of the multistep cancerogenesis. Furthermore, dedifferentiation emerged as a general hallmark of cancer evolution and a common denominator of cross-resistance to both targeted and immunotherapy. In this review, we summarize the histopathological features, the genetic and epigenetic bases underlying the dedifferentiated phenotype in melanomas and provide additional support that dedifferentiation is a mechanism of resistance to immunotherapy and targeted therapy.


Assuntos
Melanoma/genética , Melanoma/terapia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/terapia , Animais , Desdiferenciação Celular/fisiologia , Reprogramação Celular/fisiologia , Epigênese Genética , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia
12.
Gene ; 759: 144964, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32717308

RESUMO

BACKGROUND: Mucosal melanoma is a tumor caused by the malignant transformation of pigment-producing cells and can arise from any mucosal tissue where melanocytes are present. Due to its rarity, the mucosal melanoma subtype is poorly described, and its genetic characteristics are infrequently studied. The discovery or confirmation of new mucosal melanoma susceptibility genes will provide important insights for the study of its pathogenesis. MATERIALS AND METHODS: We performed deep targeted sequencing of 100 previously reported melanoma-related genes in 39 mucosal melanoma samples and a gene-level loss-of-function (LOF) variant enrichment analysis for mucosal melanoma from different incidence sites. RESULTS: We detected 7,589 variants in these samples, and 484 were LOF variants (gain or loss of a stop codon, missense, and splice site). Four different gene-level enrichment analyses revealed that FSIP1 (fibrous sheath interacting protein 1) is a susceptibility gene for oral mucosal melanoma (OR = 0.33, PChi = 4.05 × 10-2, Pburden = 3.06 × 10-2, Pskat = 3.01 × 10-2, Pskato = 3.01 × 10-2), whereas the different methods did not detect a significant susceptibility gene for the other subtypes. CONCLUSIONS: In our study, a susceptibility gene for oral mucosal melanoma was confirmed in a Chinese Han population, and these findings contribute to a better genetic understanding of mucosal melanoma of different subtypes.


Assuntos
Proteínas de Transporte/genética , Mutação com Perda de Função , Melanoma/genética , Proteínas de Plasma Seminal/genética , Idoso , Feminino , Humanos , Masculino , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/classificação , Melanoma/patologia , Pessoa de Meia-Idade , Membrana Mucosa/metabolismo , Membrana Mucosa/patologia
13.
Nat Commun ; 11(1): 3326, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620791

RESUMO

Tumour cells adapt to nutrient deprivation in vivo, yet strategies targeting the nutrient poor microenvironment remain unexplored. In melanoma, tumour cells often experience low glutamine levels, which promote cell dedifferentiation. Here, we show that dietary glutamine supplementation significantly inhibits melanoma tumour growth, prolongs survival in a transgenic melanoma mouse model, and increases sensitivity to a BRAF inhibitor. Metabolomic analysis reveals that dietary uptake of glutamine effectively increases the concentration of glutamine in tumours and its downstream metabolite, αKG, without increasing biosynthetic intermediates necessary for cell proliferation. Mechanistically, we find that glutamine supplementation uniformly alters the transcriptome in tumours. Our data further demonstrate that increase in intra-tumoural αKG concentration drives hypomethylation of H3K4me3, thereby suppressing epigenetically-activated oncogenic pathways in melanoma. Therefore, our findings provide evidence that glutamine supplementation can serve as a potential dietary intervention to block melanoma tumour growth and sensitize tumours to targeted therapy via epigenetic reprogramming.


Assuntos
Proliferação de Células/efeitos dos fármacos , Suplementos Nutricionais , Epigênese Genética/efeitos dos fármacos , Glutamina/farmacologia , Melanoma/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Epigênese Genética/genética , Glutamina/administração & dosagem , Histonas/metabolismo , Humanos , Lisina/metabolismo , Masculino , Melanoma/genética , Melanoma/patologia , Metilação/efeitos dos fármacos , Camundongos Nus , Transdução de Sinais/genética , Transcriptoma/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
14.
BMC Bioinformatics ; 21(1): 329, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703153

RESUMO

BACKGROUND: Melanoma phenotype and the dynamics underlying its progression are determined by a complex interplay between different types of regulatory molecules. In particular, transcription factors (TFs), microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) interact in layers that coalesce into large molecular interaction networks. Our goal here is to study molecules associated with the cross-talk between various network layers, and their impact on tumor progression. RESULTS: To elucidate their contribution to disease, we developed an integrative computational pipeline to construct and analyze a melanoma network focusing on lncRNAs, their miRNA and protein targets, miRNA target genes, and TFs regulating miRNAs. In the network, we identified three-node regulatory loops each composed of lncRNA, miRNA, and TF. To prioritize these motifs for their role in melanoma progression, we integrated patient-derived RNAseq dataset from TCGA (SKCM) melanoma cohort, using a weighted multi-objective function. We investigated the expression profile of the top-ranked motifs and used them to classify patients into metastatic and non-metastatic phenotypes. CONCLUSIONS: The results of this study showed that network motif UCA1/AKT1/hsa-miR-125b-1 has the highest prediction accuracy (ACC = 0.88) for discriminating metastatic and non-metastatic melanoma phenotypes. The observation is also confirmed by the progression-free survival analysis where the patient group characterized by the metastatic-type expression profile of the motif suffers a significant reduction in survival. The finding suggests a prognostic value of network motifs for the classification and treatment of melanoma.


Assuntos
Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Melanoma/genética , RNA Longo não Codificante/metabolismo , Biologia Computacional/métodos , Humanos , Melanoma/metabolismo , Melanoma/mortalidade , Melanoma/patologia , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Fenótipo , RNA-Seq , Fatores de Transcrição/metabolismo
15.
Nat Commun ; 11(1): 3588, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680985

RESUMO

Tumors subvert immune cell function to evade immune responses, yet the complex mechanisms driving immune evasion remain poorly understood. Here we show that tumors induce de novo steroidogenesis in T lymphocytes to evade anti-tumor immunity. Using a transgenic steroidogenesis-reporter mouse line we identify and characterize de novo steroidogenic immune cells, defining the global gene expression identity of these steroid-producing immune cells and gene regulatory networks by using single-cell transcriptomics. Genetic ablation of T cell steroidogenesis restricts primary tumor growth and metastatic dissemination in mouse models. Steroidogenic T cells dysregulate anti-tumor immunity, and inhibition of the steroidogenesis pathway is sufficient to restore anti-tumor immunity. This study demonstrates T cell de novo steroidogenesis as a mechanism of anti-tumor immunosuppression and a potential druggable target.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Melanoma/imunologia , Esteroides/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular Tumoral , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/imunologia , Humanos , Evasão da Resposta Imune , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Knockout , Esteroides/biossíntese
16.
Mol Genet Genomics ; 295(5): 1239-1252, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32529263

RESUMO

The genetic mechanisms underlying cutaneous melanoma onset and progression need to be further understood to improve patients' care. Several studies have focused on the genetic determinism of melanoma development in the MeLiM pig, a biomedical model of cutaneous melanoma. The objective of this study was to better describe the influence of a particular genomic region on melanoma progression in the MeliM model. Indeed, a large region of the Sus scrofa chromosome 1 has been identified by linkage and association analyses, but the causal mechanisms have remained elusive. To deepen the analysis of this candidate region, a dedicated SNP panel was used to fine map the locus, downsizing the interval to less than 2 Mb, in a genomic region located within a large gene desert. Transcription from this locus was addressed using a tiling array strategy and further validated by RT-PCR in a large panel of tissues. Overall, the gene desert showed an extensive transcriptional landscape, notably dominated by repeated element transcription in tumor and fetal tissues. The transcription of LINE-1 and PERVs has been confirmed in skin and tumor samples from MeLiM pigs. In conclusion, although this study still does not identify a candidate mutation for melanoma occurrence or progression, it highlights a potential role of repeated element transcriptional activity in the MeLiM model.


Assuntos
Cromossomos de Mamíferos/genética , Perfilação da Expressão Gênica/veterinária , Elementos Nucleotídeos Longos e Dispersos , Melanoma/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Cutâneas/genética , Animais , Mapeamento Cromossômico , Modelos Animais de Doenças , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Sus scrofa , Suínos
17.
Nat Commun ; 11(1): 2718, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483191

RESUMO

Genome-wide association studies (GWAS) have identified ~20 melanoma susceptibility loci, most of which are not functionally characterized. Here we report an approach integrating massively-parallel reporter assays (MPRA) with cell-type-specific epigenome and expression quantitative trait loci (eQTL) to identify susceptibility genes/variants from multiple GWAS loci. From 832 high-LD variants, we identify 39 candidate functional variants from 14 loci displaying allelic transcriptional activity, a subset of which corroborates four colocalizing melanocyte cis-eQTL genes. Among these, we further characterize the locus encompassing the HIV-1 restriction gene, MX2 (Chr21q22.3), and validate a functional intronic variant, rs398206. rs398206 mediates the binding of the transcription factor, YY1, to increase MX2 levels, consistent with the cis-eQTL of MX2 in primary human melanocytes. Melanocyte-specific expression of human MX2 in a zebrafish model demonstrates accelerated melanoma formation in a BRAFV600E background. Our integrative approach streamlines GWAS follow-up studies and highlights a pleiotropic function of MX2 in melanoma susceptibility.


Assuntos
Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Melanoma/genética , Mutação , Proteínas de Resistência a Myxovirus/genética , Polimorfismo de Nucleotídeo Único , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação da Expressão Gênica , Genes Reporter/genética , Células HEK293 , Humanos , Melanócitos/metabolismo , Melanoma/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Locos de Características Quantitativas/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
18.
Lancet ; 395(10240): 1835-1844, 2020 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-32534646

RESUMO

BACKGROUND: IMspire150 aimed to evaluate first-line combination treatment with BRAF plus MEK inhibitors and immune checkpoint therapy in BRAFV600 mutation-positive advanced or metastatic melanoma. METHODS: IMspire150 was a randomised, double-blind, placebo-controlled phase 3 study done at 112 institutes in 20 countries. Patients with unresectable stage IIIc-IV, BRAFV600 mutation-positive melanoma were randomly assigned 1:1 to 28-day cycles of atezolizumab, vemurafenib, and cobimetinib (atezolizumab group) or atezolizumab placebo, vemurafenib, and cobimetinib (control group). In cycle 1, all patients received vemurafenib and cobimetinib only; atezolizumab placebo was added from cycle 2 onward. Randomisation was stratified by lactate dehydrogenase concentration and geographical region. Blinding for atezolizumab was achieved by means of an identical intravenous placebo, and blinding for vemurafenib was achieved by means of a placebo tablet. The primary outcome was investigator-assessed progression-free survival. This trial (ClinicalTrials.gov, NCT02908672) is ongoing but no longer recruiting patients. FINDINGS: Between Jan 13, 2017, and April 26, 2018, 777 patients were screened and 514 were enrolled and randomly assigned to the atezolizumab group (n=256) or control group (n=258). At a median follow-up of 18·9 months (IQR 10·4-23·8), progression-free survival as assessed by the study investigator was significantly prolonged with atezolizumab versus control (15·1 vs 10·6 months; hazard ratio [HR] 0·78; 95% CI 0·63-0·97; p=0·025). Common treatment-related adverse events (>30%) in the atezolizumab and control groups were blood creatinine phosphokinase increased (51·3% vs 44·8%), diarrhoea (42·2% vs 46·6%), rash (40·9%, both groups), arthralgia (39·1% vs 28·1%), pyrexia (38·7% vs 26·0%), alanine aminotransferase increased (33·9% vs 22·8%), and lipase increased (32·2% vs 27·4%); 13% of patients in the atezolizumab group and 16% in the control group stopped all treatment because of adverse events. INTERPRETATION: The addition of atezolizumab to targeted therapy with vemurafenib and cobimetinib was safe and tolerable and significantly increased progression-free survival in patients with BRAFV600 mutation-positive advanced melanoma. FUNDING: F Hoffmann-La Roche and Genentech.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Azetidinas/uso terapêutico , Melanoma/tratamento farmacológico , Piperidinas/uso terapêutico , Vemurafenib/uso terapêutico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Azetidinas/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/genética , Melanoma/patologia , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Piperidinas/efeitos adversos , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas B-raf/genética , Vemurafenib/efeitos adversos
19.
PLoS One ; 15(6): e0234707, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555626

RESUMO

Despite significant development of melanoma therapies, death rates remain high. MicroRNAs, controlling posttranscriptionally gene expression, play role in development of resistance to BRAF inhibitors. The aim of the study was to assess the role of miR-410-3p in response to vemurafenib-BRAF inhibitor. FFPE tissue samples of 12 primary nodular melanomas were analyzed. With the use of Laser Capture Microdissection, parts of tumor, transient tissue, and adjacent healthy tissue were separated. In vitro experiments were conducted on human melanoma cell lines A375, G361, and SK-MEL1. IC50s of vemurafenib were determined using MTT method. Cells were transfected with miR-410-3p mimic, anti-miR-410-3p and their non-targeting controls. ER stress was induced by thapsigargin. Expression of isolated RNA was determined using qRT-PCR. We have found miR-410-3p is downregulated in melanoma tissues. Its expression is induced by vemurafenib in melanoma cells. Upregulation of miR-410-3p level increased melanoma cells resistance to vemurafenib, while its inhibition led to the decrease of resistance. Induction of ER stress increased the level of miR-410-3p. miR-410-3p upregulated the expression of AXL in vitro and correlated with markers of invasive phenotype in starBase. The study shows a novel mechanism of melanoma resistance. miR-410-3p is induced by vemurafenib in melanoma cells via ER stress. It drives switching to the invasive phenotype that leads to the response and resistance to BRAF inhibition.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Melanoma/genética , MicroRNAs/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Vemurafenib/farmacologia , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Vemurafenib/uso terapêutico
20.
Mol Cell ; 79(3): 472-487.e10, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32531202

RESUMO

It is widely assumed that decreasing transcription factor DNA-binding affinity reduces transcription initiation by diminishing occupancy of sequence-specific regulatory elements. However, in vivo transcription factors find their binding sites while confronted with a large excess of low-affinity degenerate motifs. Here, using the melanoma lineage survival oncogene MITF as a model, we show that low-affinity binding sites act as a competitive reservoir in vivo from which transcription factors are released by mitogen-activated protein kinase (MAPK)-stimulated acetylation to promote increased occupancy of their regulatory elements. Consequently, a low-DNA-binding-affinity acetylation-mimetic MITF mutation supports melanocyte development and drives tumorigenesis, whereas a high-affinity non-acetylatable mutant does not. The results reveal a paradoxical acetylation-mediated molecular clutch that tunes transcription factor availability via genome-wide redistribution and couples BRAF to tumorigenesis. Our results further suggest that p300/CREB-binding protein-mediated transcription factor acetylation may represent a common mechanism to control transcription factor availability.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genoma , Melanoma/genética , Fator de Transcrição Associado à Microftalmia/genética , Processamento de Proteína Pós-Traducional , Neoplasias Cutâneas/genética , Acetilação , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Sequência Conservada , Elementos Facilitadores Genéticos , Feminino , Xenoenxertos , Humanos , Masculino , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos Nus , Fator de Transcrição Associado à Microftalmia/química , Fator de Transcrição Associado à Microftalmia/metabolismo , Motivos de Nucleotídeos , Regiões Promotoras Genéticas , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Peixe-Zebra
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