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2.
Nat Med ; 25(6): 929-935, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171876

RESUMO

Melanoma treatment has progressed in the past decade with the development and approval of immune checkpoint inhibitors targeting programmed death 1 (PD-1) or its ligand (PD-L1) and cytotoxic T lymphocyte-associated antigen 4, as well as small molecule inhibitors of BRAF and/or MEK for the subgroup of patients with BRAFV600 mutations1-9. BRAF/MEK-targeted therapies have effects on the tumor microenvironment that support their combination with PD-1/PD-L1 inhibitors10-20. This phase Ib study (ClinicalTrials.gov, number NCT01656642 ) evaluated the safety and anti-tumor activity of combining atezolizumab (anti-PD-L1) with vemurafenib (BRAF inhibitor), or cobimetinib (MEK inhibitor) + vemurafenib, in patients with BRAFV600-mutated metastatic melanoma. Triple combination therapy with atezolizumab + cobimetinib + vemurafenib, after a 28-d run-in period with cobimetinib + vemurafenib, had substantial but manageable toxicity. Exploratory biomarker data show that the cobimetinib + vemurafenib run-in was associated with an increase in proliferating CD4+ T-helper cells but not with an increase in T-regulatory cells, as observed in the vemurafenib-only run-in period. The confirmed objective response rate was 71.8% (95% confidence interval 55.1-85.0). The estimated median duration of response was 17.4 months (95% confidence interval 10.6-25.3) with ongoing response in 39.3% of patients after 29.9 months of follow-up. Further investigation in a phase III trial is underway.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Anticorpos Monoclonais/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Azetidinas/administração & dosagem , Antígeno B7-H1/antagonistas & inibidores , Estudos de Coortes , Humanos , Estimativa de Kaplan-Meier , MAP Quinase Quinase Quinases/antagonistas & inibidores , Melanoma/secundário , Mutação , Piperidinas/administração & dosagem , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Vemurafenib/administração & dosagem
3.
Anticancer Res ; 39(4): 1777-1783, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30952717

RESUMO

BACKGROUND/AIM: Conventional in vitro assays measure the effect of drugs on total cells, while separating the effect to those on tumor and non-tumor cells is important for assessing drug specificity. Our aim was to evaluate the feasibility of separating the efficacy of vemurafenib on tumor and non-tumor cells in a mixed culture. MATERIALS AND METHODS: Melanoma A2058 cells and CCD18Co non-tumor cells were mixed and treated with vemurafenib. DNA was subjected to digital PCR to determine the ratio of the mutant 1799A to the wild-type 1799T alleles and viabilities of total cells were subsequently calculated as percentages of tumor and non-tumor cells. RESULTS: The set-up proportion of tumor cells correlated well with the calculated one. The calculated viability of tumor cells decreased with increasing doses of vemurafenib while that of the non-tumor cells remained rather constant. Variability of digital PCR data was high. CONCLUSION: Using the BRAF mutation 1799T>A to separate the response of tumor and non-tumor cells to a drug, such as vemurafenib, is feasible, supporting a foundation for a genetic in vitro tool for testing drug efficacy and specificity.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/genética , Análise Mutacional de DNA/métodos , Melanoma/tratamento farmacológico , Mutação , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/tratamento farmacológico , Vemurafenib/farmacologia , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estudos de Viabilidade , Humanos , Melanoma/enzimologia , Melanoma/genética , Melanoma/patologia , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
5.
Front Biosci (Schol Ed) ; 11: 193-202, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30844744

RESUMO

Vemurafenib is a B-raf inhibitor which is widely used in treatment of melanoma patients with B-RAF V600E mutation. Majority of patients treated with vemurafenib develop resistance against the drug. Here, we asssessed the effectiveness of a combination drug therapy in vemurafenib resistant melanoma cells. Vemurafenib resistant A375 melanoma cells (A375Res cells) were developed by growing parental cells in increasing concentrations of the drug. The A375Res cells were 50 times more resistant (higher IC50 value), had reduced cell doubling time, were less responsive to the antiproliferative activity of Vemurafenib and showed increased tumor forming potential as compared to the parental cells. Vemurafenib inhibited phosphorylation of MEK 1/2 and ERK 1/2 at the concentrations far less than those that were effective in parental cells. Compared to the other drugs sorafenib in combination with vemurafenib significantly inhibited proliferation of A375Res cells. These findings show that Sorafenib, in combination with Vemurafenib, is a more effective method for treatment of melanoma with B-Raf 600E mutation.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Melanoma/tratamento farmacológico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Sorafenibe/farmacologia , Vemurafenib/farmacologia , Antineoplásicos/farmacologia , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sinergismo Farmacológico , Humanos , Indóis , Concentração Inibidora 50 , Mutação , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Sulfonamidas
6.
BMC Cancer ; 19(1): 266, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30909892

RESUMO

BACKGROUND: Recent advances in the treatment of melanoma that involve immunotherapy and B-Raf inhibition have revolutionised cancer care for this disease. However, an un-met clinical need remains in B-Raf inhibitor resistant patients where first-generation B-Raf inhibitors provide only short-term disease control. In these cases, B-Raf inhibition leads to paradoxical activation of the C-Raf - MEK - ERK signalling pathway, followed by metastasis. PDE8A has been shown to directly interact with and modulate the cAMP microdomain in the vicinity of C-Raf. This interaction promotes C-Raf activation by attenuating the PKA-mediated inhibitory phosphorylation of the kinase. METHODS: We have used a novel cell-penetrating peptide agent (PPL-008) that inhibits the PDE8A - C-Raf complex in a human malignant MM415 melanoma cell line and MM415 melanoma xenograft mouse model to investigate ERK MAP kinase signalling. RESULTS: We have demonstrated that the PDE8A - C-Raf complex disruptor PPL-008 increased inhibitory C-Raf-S259 phosphorylation and significantly reduced phospho-ERK signalling. We have also discovered that the ability of PPL-008 to dampen ERK signalling can be used to counter B-Raf inhibitor-driven paradoxical activation of phospho-ERK in MM415 cells treated with PLX4032 (Vemurafenib). PPL-008 treatment also significantly retarded the growth of these cells. When applied to a MM415 melanoma xenograft mouse model, PPL-008C penetrated tumour tissue and significantly reduced phospho-ERK signalling in that domain. CONCLUSION: Our data suggests that the PDE8A-C-Raf complex is a promising therapeutic treatment for B-Raf inhibitor resistant melanoma.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Peptídeos Penetradores de Células/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-raf/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/farmacologia , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/metabolismo , Camundongos , Ligação Proteica/efeitos dos fármacos , Vemurafenib/administração & dosagem , Vemurafenib/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Dermatol Clin ; 37(2): 159-168, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30850038

RESUMO

Melanoma is rapidly evolving because of advances in noninvasive diagnosis, targeted therapies, and improved prognostic methods. This article discusses what is new in melanoma risk factors, prevention, clinical management, and targeted treatment. The incidence continues to increase worldwide, whereas mortality is steadily improving. This trend reinforces the importance of dermatologists comprehensively understanding all aspects of melanoma. Further research is needed to continue making a material impact on outcomes for patients.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Procedimentos Cirúrgicos Dermatológicos , Melanoma/terapia , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Biópsia , Café , Espectroscopia Dielétrica , Detecção Precoce de Câncer , Predisposição Genética para Doença , Genômica , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Ipilimumab/uso terapêutico , Melanoma/diagnóstico , Melanoma/epidemiologia , Melanoma/genética , Microscopia Confocal , Nivolumabe/uso terapêutico , Inibidores da Fosfodiesterase 5/uso terapêutico , Prevenção Primária , Prognóstico , Fatores de Proteção , Fatores de Risco , Prevenção Secundária , Biópsia de Linfonodo Sentinela , Fator de Proteção Solar , Protetores Solares/uso terapêutico , Ultrassonografia , Vemurafenib/uso terapêutico
8.
Cancer Treat Rev ; 74: 43-48, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30798169

RESUMO

BACKGROUND: The spectrum of treatment options for patients with metastatic BRAF-mutated melanoma is broad, spanning multiple treatment classes. However, there is a lack of head-to-head evidence comparing targeted and immunotherapies. The purpose of this study is to conduct a network meta-analysis (NMA) in previously untreated, BRAF-mutated melanoma patients and estimate the relative efficacy of systemic therapies for this patient population at the treatment level. METHODS: The literature review included searches of MEDLINE, EMBASE, and the Cochrane Central Registry of Controlled Trials (CENTRAL) to November 2018. Randomized controlled trials of previously untreated patients with advanced melanoma were eligible if at least one intervention was either a targeted or immune therapy. Relative treatment effects were estimated by fixed effect Bayesian NMAs on progression-free survival (PFS) and overall survival (OS), based on the hazard ratio. RESULTS: Combination dabrafenib with trametinib (HR 0.22 [95% CrI 0.17, 0.28] vs dacarbazine) and combination vemurafenib with cobimetinib (HR 0.22 [95% CrI 0.17, 0.29] vs dacarbazine) were likely to rank as the most favorable treatment options for PFS, while combination nivolumab with ipilimumab was likely to be the most efficacious in terms of OS (HR 0.33 [0.24, 0.47] vs dacarbazine). CONCLUSIONS AND RELEVANCE: The findings highlight the efficacy of combination PD-1 with CTLA-4 inhibitors and combination BRAF with MEK inhibitors in the treatment of advanced melanoma. However, as few trials informed each treatment comparison, research is needed to further refine our understanding of this complex and rapidly evolving treatment landscape.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Azetidinas/administração & dosagem , Dacarbazina/administração & dosagem , Humanos , Imidazóis/administração & dosagem , Melanoma/enzimologia , Terapia de Alvo Molecular , Mutação , Oximas/administração & dosagem , Piperidinas/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/metabolismo , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Vemurafenib/administração & dosagem
9.
Food Chem Toxicol ; 125: 549-561, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30738990

RESUMO

Cutaneous melanoma has a high capacity to metastasize and significant resistance to conventional therapeutic protocols, which makes its treatment difficult. The combination of conventional drugs with cytostatic molecules of low toxicity has been shown to be an interesting alternative for sensitization of tumor cells to chemotherapy. In this study, we evaluated the effect of bixin, an abundant apocarotenoid present in Bixa orellana, on the sensitization of human melanoma cells (A2058) to dacarbazine treatment, an anticancer agent clinically used for the therapy of metastatic melanoma. UPLC-DAD-MS/MS analyses of bioactive extracts from B. orellana seeds led to the identification of two new apocarotenoids: 6,8'-diapocarotene-6,8'-dioic acid and 6,7'-diapocarotene-6,7'-dioic acid. After being identified as its major compound, bixin (Z-bixin) was evaluated on A2058 cells expressing the oncogenic BRAF VE600 mutation and resistant to dacarbazine treatment. Bixin promoted growth inhibition, reduced cell migration, induced apoptosis and cell cycle arrest in the G2/M phase. When associated with dacarbazine, bixin restored the sensitivity of A2058 cells to chemotherapy, enhancing its antiproliferative, anti-migratory and pro-apoptotic effects. Combined treatment also induced higher ROS (reactive oxygen species) and MDA (malondialdehyde, a lipid peroxidation marker) generation than monotreatment, suggesting that the oxidative stress caused by bixin contributes significantly to its sensitizing effect. Taken together, these data suggest that bixin exerts intrinsic antimelanoma activity by mechanisms complementary to those of dacarbazine, encouraging its use in combined therapy for cutaneous melanoma treatment.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bixaceae/química , Carotenoides/farmacologia , Dacarbazina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/isolamento & purificação , Carotenoides/isolamento & purificação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sementes/química , Neoplasias Cutâneas/tratamento farmacológico , Vemurafenib/farmacologia
10.
J Exp Clin Cancer Res ; 38(1): 48, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717768

RESUMO

BACKGROUND: As the selective inhibitor of BRAF kinase, vemurafenib exhibits effective antitumor activities in patients with V600 BRAF mutant melanomas. However, acquired drug resistance invariably develops after its initial treatment. METHODS: Immunohistochemical staining was performed to detect the expression of iNOS and hTERT, p-p65, Epcam, CD44, PCNA in mice with melanoma xenografts. The proliferation and migration of melanoma cells were detected by MTT, tumorsphere culture, cell cycle, cell apoptosis, AO/EB assay and colony formation, transwell assay and scratch assay in vitro, and tumor growth differences were observed in xenograft nude mice. Changes in the expression of key molecules in the iNOS/hTERT signaling pathways were detected by western blot. Nucleus-cytoplasm separation, and immunofluorescence analyses were conducted to explore the location of p50/p65 in melanoma cell lines. Flow cytometry assay were performed to determine the expression of CD44. Pull down assay and ChIP assay were performed to detect the binding ability of p65 at iNOS and hTERT promoters. Additionally, hTERT promoter-driven luciferase plasmids were transfected in to melanoma cells with indicated treatment to determine luciferase activity of hTERT. RESULTS: Melatonin significantly and synergistically enhanced vemurafenib-mediated inhibitions of proliferation, colony formation, migration and invasion and promoted vemurafenib-induced apoptosis, cell cycle arresting and stemness weakening in melanoma cells. Further mechanism study revealed that melatonin enhanced the antitumor effect of vemurafenib by abrogating nucleus translocation of NF-κB p50/p65 and their binding at iNOS and hTERT promoters, thereby suppressing the expression of iNOS and hTERT. The elevated anti-tumor capacity of vemurafenib upon co-treatment with melatonin was also evaluated and confirmed in mice with melanoma xenografts. CONCLUSIONS: Collectively, our results demonstrate melatonin synergizes the antitumor effect of vemurafenib in human melanoma by inhibiting cell proliferation and cancer-stem cell traits via targeting NF-κB/iNOS/hTERT signaling pathway, and suggest the potential of melatonin in antagonizing the toxicity of vemurafenib and augmenting its sensitivities in melanoma treatment.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antioxidantes/uso terapêutico , Melanoma/tratamento farmacológico , Melatonina/uso terapêutico , Células-Tronco Neoplásicas/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Telomerase/antagonistas & inibidores , Vemurafenib/uso terapêutico , Animais , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Masculino , Melatonina/farmacologia , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Vemurafenib/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Melanoma Res ; 29(2): 134-144, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30802229

RESUMO

Targeted therapy with the BRAF inhibitors vemurafenib and dabrafenib is an effective treatment regimen in patients with advanced melanoma carrying the BRAF V600E mutation. A common side effect is an enhanced rate of nonmelanoma skin cancer (NMSC). BRAF inhibition leads to a paradoxical enhanced MAPK signalling in BRAF wild-type cells, which might in part be responsible for the enhanced NMSC burden. It is known that disturbances of DNA repair result in an increased rate of NMSC. In the present study, it was investigated whether BRAF inhibitors might interfere with the repair of ultraviolet radiation-induced DNA damage in vitro. Epidermal keratinocytes of 11 Caucasian donors were treated with vemurafenib or dabrafenib and, 24 h later, exposed to ultraviolet A. DNA damage and repair capacity were analysed using south-western slot blot detecting cyclobutane pyrimidine dimers. Using PCR and DNA sequencing, RAS mutations and human papilloma virus genes were investigated. RNA expression was determined using a Gene Expression Chip and qRT-PCR. In 36% of keratinocytes, vemurafenib hampers the repair of ultraviolet A-induced DNA damage. No changes in DNA repair were observed with dabrafenib, indicating a possible substance-specific effect of vemurafenib. In none of the keratinocytes, pre-existing RAS mutations or human papilloma virus-associated DNA sequences were detected. The expression of the interferon-related damage resistance signature is decreased upon vemurafenib treatment in 36% of donors. The enhanced rate of NMSC in patients treated with vemurafenib might be partly related to a vemurafenib-driven impaired capacity for DNA repair.


Assuntos
Antineoplásicos/uso terapêutico , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Neoplasias Cutâneas/tratamento farmacológico , Raios Ultravioleta/efeitos adversos , Vemurafenib/uso terapêutico , Antineoplásicos/farmacologia , Humanos , Neoplasias Cutâneas/patologia , Vemurafenib/farmacologia
12.
Int J Clin Pharmacol Ther ; 57(5): 259-263, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30704555

RESUMO

Vemurafenib and cobimetinib are extremely effective in treating V600E-mutated metastatic melanoma, but their use is associated with toxic cardiac effects. Vemurafenib-induced prolonged QTc interval may be associated with ventricular fibrillation and sudden cardiac death. Cobimetinib-induced myocardial damage may lead to severely reduced heart function and lethal heart failure. Few data are available about the time course of recovery after these side effects. We provide the first description of cardiac recovery after potentially fatal cardiac side effects due to vemurafenib and cobimetinib administration. A 51-year-old woman was admitted to our hospital with diarrhea, vomiting, and asthenia. At admission, her left ventricular ejection fraction (LVEF) was severely reduced and QTc interval was extremely elongated (normal range QTc ≤ 440 ms). Blood levels of troponin I (normal values below 0.07 ng/mL) and brain natriuretic peptide (brain natriuretic peptide (BNP), normal range < 100 pg/mL) were elevated. During hospitalization, she developed recurrent runs of torsades de pointes degenerating into ventricular fibrillation, requiring direct current electric shock (DC shocks). Vemurafenib and cobimetinib were discontinued. Three weeks later, QTc was still higher than 500 ms and LVEF lower than 30%: an implantable cardioverter-defibrillator (ICD) was implanted. Myocardial function improved within 1 month, and QTc intervals became 500 ms 1 week later. After 6 months, a normal ejection fraction (> 55%) was observed, and the QTc interval was 455 ms. The patient died rather from metastatic melanoma recurrence 8 months later. This case report highlights the time-course of recovery after combined vemurafenib-cobimetinib-induced severe myocardial damage. Further research is warranted to assess whether and how antineoplastic therapy may be resumed after QT normalization and heart function recovery.
.


Assuntos
Azetidinas/efeitos adversos , Cardiotoxicidade , Piperidinas/efeitos adversos , Vemurafenib/efeitos adversos , Feminino , Humanos , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia
13.
EBioMedicine ; 39: 194-206, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30611716

RESUMO

BACKGROUND: BRAF inhibitor (BRAF-I) therapy for melanoma patients harboring the V600E mutation is initially highly effective, but almost all patients relapse within a few months. Understanding the molecular mechanisms behind BRAF-I responsiveness and acquired resistance is therefore an important issue. Here we assessed the role of urokinase type plasminogen activator receptor (uPAR) as a potentially valuable biomarker in the acquisition of BRAF-I resistance in V600E mutant melanoma cells. METHODS: We examined uPAR and EGFR levels by real time PCR and western blot analysis. uPAR loss of function was realized by knocking down uPAR by RNAi or using M25, a peptide that uncouples uPAR-integrin interaction. We investigated uPAR-ß1integrin-EGFR association by co-immunoprecipitation and confocal immuno-fluorescence analysis. Acquired resistance to BRAF-I was generated by chronic exposure of cells to vemurafenib. FINDINGS: We proved that uPAR knockdown in combination with vemurafenib inhibits melanoma cell proliferation to greater extent than either treatment alone causing a decrease in AKT and ERK1/2 phosphorylation. Conversely, we demonstrated that uPAR enforced over-expression results in reduced sensitivity to BRAF inhibition. Moreover, by targeting uPAR and EGFR interaction with an integrin antagonist peptide we restored vemurafenib responsiveness in melanoma resistant cells. Furthermore, we found significant detectable uPAR and EGFR levels in tumor biopsies of 4 relapsed patients. INTERPRETATION: We disclosed an unpredicted mechanism of reduced sensitiveness to BRAF inhibition, driven by elevated levels of uPAR and identified a potential therapeutic strategy to overcome acquired resistance. FUNDS: Associazione Italiana Ricerca sul Cancro (AIRC); Ente Cassa di Risparmio di Firenze.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Melanoma/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Vemurafenib/farmacologia , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Masculino , Melanoma/tratamento farmacológico , Melanoma/genética , Pessoa de Meia-Idade , Mutação , Ligação Proteica , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos
14.
Melanoma Res ; 29(2): 178-186, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30653029

RESUMO

Sixteen BRAF-mutation positive, metastatic melanoma patients with highly advanced disease received combination therapy of vemurafenib and ipilimumab as an individual treatment decision. Our aim was to assess the role of fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT) in the evaluation of the clinical benefit (CB) of this combination treatment. After clinical improvement under vemurafenib monotherapy, four cycles of ipilimumab were additionally administered. F-FDG PET/CT was performed before the start, after two cycles and after completion of the combined ipilimumab/vemurafenib treatment. PET-based patient response evaluation to treatment was based on the European Organization for Research and Treatment of Cancer and the PET Response Evaluation Criteria for Immunotherapy criteria. Progression-free survival (PFS) from the end of combination treatment was calculated. According to their best clinical response at the end of combination treatment, eight patients showed CB and eight patients had no-CB. Two patients revealed extraordinary good clinical outcome with PFS of more than 5 years. Overall, 13 out of 16 patients were correctly classified by the European Organization for Research and Treatment of Cancer and 15 out of 16 by the PET Response Evaluation Criteria for Immunotherapy criteria. Median PFS was 8.8 months among PET-responders and 3.6 months among nonresponders. During immunotherapy administration seven patients developed radiologic signs of immune-related adverse events (irAEs), with colitis and arthritis being the most frequent ones; these patients had a significantly longer PFS than those without irAEs (P=0.036). F-FDG PET/CT is a valuable tool for the evaluation of patients receiving a combination of targeted treatment and immunotherapy. The appearance of irAEs on PET/CT might correlate with benefit to immunotherapy.


Assuntos
Antineoplásicos/uso terapêutico , Fluordesoxiglucose F18/uso terapêutico , Ipilimumab/uso terapêutico , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/tratamento farmacológico , Vemurafenib/uso terapêutico , Adulto , Idoso , Antineoplásicos/farmacologia , Feminino , Fluordesoxiglucose F18/farmacologia , Humanos , Ipilimumab/farmacologia , Estudos Longitudinais , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Segunda Neoplasia Primária , Neoplasias Cutâneas/patologia , Resultado do Tratamento , Vemurafenib/farmacologia
15.
Am J Dermatopathol ; 41(3): 214-217, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30601209

RESUMO

Cutaneous toxicities associated with BRAF inhibitor treatment in patients with metastatic melanoma have been well described. We present a rare association of granulomatous dermatitis in association with the BRAF inhibitor vemurafenib. Three patients with metastatic melanoma all presented with asymptomatic papular eruptions 8-21 months into vemurafenib therapy. Skin biopsies confirmed the diagnosis of granulomatous dermatitis. Other causes of granulomatous dermatitis including infectious agents and sarcoid were excluded. Treatment with potent topical and oral steroids improved the eruptions, but only after the cessation of vemurafenib did all 3 cases of granulomatous dermatitis completely resolve within 2 weeks. It is important to recognize that this association, unlike most other BRAF inhibitor-related skin toxicities, can occur many months after commencement of therapy and that vemurafenib treatment can be continued without clinically significant adverse effects.


Assuntos
Antineoplásicos/efeitos adversos , Erupção por Droga/etiologia , Granuloma/induzido quimicamente , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Pele/efeitos dos fármacos , Vemurafenib/toxicidade , Biópsia , Erupção por Droga/diagnóstico , Feminino , Granuloma/diagnóstico , Humanos , Melanoma/enzimologia , Melanoma/secundário , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas B-raf/metabolismo , Pele/patologia , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia , Fatores de Tempo , Resultado do Tratamento
16.
Eur J Med Chem ; 163: 243-255, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30529543

RESUMO

Despite various applications of kinase inhibitors in oncology and inflammatory diseases, the emergence of resistance still remains the major barrier to achieve long-term remission in cancer treatment. With the aim of overcoming the resistance induced by type IIB BRaf V600E selective inhibitor vemurafenib, and further ameliorating the antiproliferative activity, a novel type IIA Pan-Raf inhibitors Ia-Io based on pyrrolo[2,3-d] pyrimidine scaffold were designed and evaluated in this work. Herein, we tried to improve the cellular potency of the target compounds by increasing their solubility. Among them, Il, with the solubility of 0.107 mg/mL, demonstrated favorable cellular activity against vemurafenib-resistant carcinoma cells including BRafWT phenotypic melanoma SK-MEL-2 and BRafV600E phenotypic colorectal cancer HT-29 cell lines. Based on the well solubility, Il exhibited good metabolic stability compared to sorafenib and showed favorable pharmacokinetic profiles in rats. As for the biological mechanism research, Il had the similar P-ERK kinase inhibitory activity in A375 and SK-Mel-2 cells as our previously lead P-2. Il may become a good candidate compound to overcome the resistance associated with vemurafenib.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Células HT29 , Humanos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/farmacologia , Ratos , Solubilidade , Relação Estrutura-Atividade , Vemurafenib/farmacologia
17.
J Cutan Pathol ; 46(3): 190-194, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30552700

RESUMO

BACKGROUND: BRAF inhibition has improved overall survival in patients with BRAF mutant melanoma, but this is associated with a range of known and predictable cutaneous side effects, including squamous cell carcinomas associated with RAS mutations. METHODS: We identified three severely dysplastic nevi, one atypical intraepidermal melanocytic proliferation, and four melanoma in situ lesions, newly arising in four patients undergoing treatment with vemurafenib. To characterize mutations in these atypical melanocytic lesions, we used a custom iPlex panel detecting 74 mutations in 13 genes known to play a role in melanoma pathogenesis. RESULTS: We identified an NRAS mutation at codon 61 (Q61R) and a rare BRAF exon 11 mutation (G466A) in atypical melanocytic lesions that arose in patients treated with vemurafenib. CONCLUSION: There appears to be development or accelerated growth of atypical melanocytic lesions in the setting of BRAF inhibition. Our results underscore the need for careful surveillance for melanocytic lesions in patients on BRAF inhibitor therapy and shed light on potential mechanisms for melanoma pathogenesis in the context of BRAF pathway blockade. Further studies are warranted to show a causal relationship.


Assuntos
Antineoplásicos/efeitos adversos , GTP Fosfo-Hidrolases/genética , Melanoma/tratamento farmacológico , Proteínas de Membrana/genética , Segunda Neoplasia Primária/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/tratamento farmacológico , Vemurafenib/efeitos adversos , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Mutação , Segunda Neoplasia Primária/induzido quimicamente , Estudos Retrospectivos , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética
19.
Nat Commun ; 9(1): 5272, 2018 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-30532051

RESUMO

Antipsychotic (AP) drugs are used to treat psychiatric disorders but are associated with significant weight gain and metabolic disease. Increased food intake (hyperphagia) appears to be a driving force by which APs induce weight gain but the mechanisms are poorly understood. Here we report that administration of APs to C. elegans induces hyperphagia by a mechanism that is genetically distinct from basal food intake. We exploit this finding to screen for adjuvant drugs that suppress AP-induced hyperphagia in C. elegans and mice. In mice AP-induced hyperphagia is associated with a unique hypothalamic gene expression signature that is abrogated by adjuvant drug treatment. Genetic analysis of this signature using C. elegans identifies two transcription factors, nhr-25/Nr5a2 and nfyb-1/NFYB to be required for AP-induced hyperphagia. Our study reveals that AP-induced hyperphagia can be selectively suppressed without affecting basal food intake allowing for novel drug discovery strategies to combat AP-induced metabolic side effects.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Ingestão de Alimentos/genética , Hiperfagia/genética , Animais , Antipsicóticos/toxicidade , Fator de Ligação a CCAAT/genética , Quimioterapia Adjuvante , Proteínas de Ligação a DNA/genética , Ingestão de Alimentos/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Hiperfagia/induzido quimicamente , Hiperfagia/tratamento farmacológico , Hipotálamo/metabolismo , Camundongos , Fenótipo , Fatores de Transcrição/genética , Vemurafenib/farmacologia
20.
Cell Physiol Biochem ; 49(3): 1143-1162, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30196299

RESUMO

BACKGROUND/AIMS: Anaplastic thyroid cancer (ATC), with 25% BRAFV600E mutation, is one of the most lethal human malignancies that currently has no effective therapy. Vemurafenib, a BRAFV600E inhibitor, has shown promise in clinical trials, including ATC patients, but is being hampered by the acquisition of drug resistance. Therefore, combination therapy that includes BRAFV600E inhibition and avoids resistance is a clinical need. METHODS: ATC cell lines 8505C (BRAFV600E/mt), SW1736 (BRAFV600E/mt), KAT18 (BRAFV600E/wt) and Cal-62(BRAFV600E/wt) cells were used in the study. The ability of S100A knockout or /and in combination with the BRAF inhibitor vemurafenib on growth, apoptosis, invasion and apoptosis in ATC cells in vitro was demonstrated by MTT and BrdUrd incorporation assay, Annexin-V-FITC staining analyzed by flow cytometry, Transwell migration and Matrigel invasion assay. S100A4,pERK1/2, pAKT and pROCK1/2 protein was detected by western blot assay; Small molecule inhibitors of Y27632, U0126, MK-2206 and constitutively active forms of pCDNA-Myc-pERK, pCMV6-HA-Akt, pCMV-RhoA were employed, and the mechanistic studies were performed. We assessed the efficiency of in vivo combination treatment with S100A4 knockout and Vemurafenib on tumors. RESULTS: S100A4 knockout induced apoptosis and reduced proliferation by inactivation of pAKT and pERK signals, and inhibited invasion and migration by inactivation of pAKT and RhoA/ROCK1/2 signals in 8505C or Cal-62 cells in vitro, and vice versa in SW1736 and KAT18 cells. Vemurafenib did not affect apoptosis of both 8505C and SW1736 cells, but reduced proliferation via arresting cell cycle, and promoted cell migration and invasion in vitro. Combination treatment with S100A4 knockdown and vemurafenib reduced cell proliferation, migration and invasion in vitro compared to the S100A4 knockdown or Vemurafenib alone. Vemurafenib treatment resulted in a transient inhibition of pERK expression and gradually activation of pAKT expression, but quickly recovery from ERK1/2 activation inhibition by vemurafenib treatment in 4 h for SW1736 and 8505C cells. Combined treatment completely inhibited ERK1/2 and AKT activation during 48 h. In an in vivo mouse model of SW1736 and 8505C, vemurafenib treatment alone did not significantly inhibit tumor growth in both of the tumors, but inhibited tumor growth in combined groups. CONCLUSION: Our results show S100A4 knockout alone inhibits ATC cells (rich endogenous S100A4) survival and invasion, regardless of the BRAFV600E status, and potentiates the effect of vemurafenib on tumor regression in vitro and in vivo. In addition, S100A4 knockout potently inhibits the recovery from ERK1/2 activation inhibition and the AKT activation following vemurafenib treatment and reversed the vemurafenib resistance. This therapeutic combination may be of benefit in patients with ATC.


Assuntos
Antineoplásicos/uso terapêutico , Indóis/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo , Sulfonamidas/uso terapêutico , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Indóis/farmacologia , Camundongos , Camundongos Knockout , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100/antagonistas & inibidores , Proteína A4 de Ligação a Cálcio da Família S100/genética , Sulfonamidas/farmacologia , Carcinoma Anaplásico da Tireoide/metabolismo , Carcinoma Anaplásico da Tireoide/patologia , Vemurafenib
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