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1.
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
2.
Nat Commun ; 11(1): 4370, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873792

RESUMO

BRAF kinase, a critical effector of the ERK signaling pathway, is hyperactivated in many cancers. Oncogenic BRAFV600E signals as an active monomer in the absence of active RAS, however, in many tumors BRAF dimers mediate ERK signaling. FDA-approved RAF inhibitors poorly inhibit BRAF dimers, which leads to tumor resistance. We found that Ponatinib, an FDA-approved drug, is an effective inhibitor of BRAF monomers and dimers. Ponatinib binds the BRAF dimer and stabilizes a distinct αC-helix conformation through interaction with a previously unrevealed allosteric site. Using these structural insights, we developed PHI1, a BRAF inhibitor that fully uncovers the allosteric site. PHI1 exhibits discrete cellular selectivity for BRAF dimers, with enhanced inhibition of the second protomer when the first protomer is occupied, comprising a novel class of dimer selective inhibitors. This work shows that Ponatinib and BRAF dimer selective inhibitors will be useful in treating BRAF-dependent tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Sítio Alostérico/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Cristalografia por Raios X , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Sistema de Sinalização das MAP Quinases/genética , Simulação de Acoplamento Molecular , Mutação , Neoplasias/genética , Neoplasias/patologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/uso terapêutico , Multimerização Proteica/efeitos dos fármacos , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas B-raf/ultraestrutura , Piridazinas/farmacologia , Piridazinas/uso terapêutico , Bibliotecas de Moléculas Pequenas , Relação Estrutura-Atividade
3.
Internist (Berl) ; 61(9): 969-979, 2020 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-32785740

RESUMO

Erdheim-Chester disease (ECD) is nowadays classified as belonging to those neoplasms with origins in the myeloid dendritic cell lines. The clonal alterations maintain a chronic inflammatory condition, which dominates the pathogenesis and clinical expression. Characteristic for ECD are many skeletal manifestations; however, the multisystem disease affects many other organs (including the respiratory tract, heart, retroperitoneum, eyes, central nervous system and endocrine system). The diagnosis is usually first made only after a disease duration of many years. This is due to the rarity of the disease and the very diffuse symptoms in addition to the heterogeneous organ manifestations. There are no uniform diagnostic criteria. The constellation of unclear polyserositis and ostealgia, possibly in association with neurological and endocrine deficiencies, should steer the suspicion towards an ECD. The diagnosis can be confirmed by an organ biopsy and the immunohistochemical examination enables the relatively certain differentiation from other forms of histiocytosis. The detection of activating oncological mutations in signal transduction pathways has opened up the possibility of targeted treatment with kinase inhibitors, such as vemurafenib for BRAF V600E mutations. Up to the discovery of activating mutations, interferon-alpha was used as the first line treatment; however, in view of the superiority of kinase inhibitors, the first line treatment with interferon-alpha currently appears to be questionable. The prognosis for untreated ECD is exceptionally poor and interferon-alpha leads to a clear improvement. Further progress is hoped for with the use of targeted treatments.


Assuntos
Doença de Erdheim-Chester/tratamento farmacológico , Interferon-alfa/uso terapêutico , Rim/fisiopatologia , Mutação/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Vemurafenib/uso terapêutico , Doença de Erdheim-Chester/diagnóstico , Doença de Erdheim-Chester/genética , Humanos , Prognóstico
4.
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
5.
Lancet Oncol ; 21(9): 1234-1243, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32818466

RESUMO

BACKGROUND: Effective treatments for patients with cholangiocarcinoma after progression on gemcitabine-based chemotherapy are urgently needed. Mutations in the BRAF gene have been found in 5% of biliary tract tumours. The combination of dabrafenib and trametinib has shown activity in several BRAFV600E-mutated cancers. We aimed to assess the activity and safety of dabrafenib and trametinib combination therapy in patients with BRAFV600E-mutated biliary tract cancer. METHODS: This study is part of an ongoing, phase 2, open-label, single-arm, multicentre, Rare Oncology Agnostic Research (ROAR) basket trial in patients with BRAFV600E-mutated rare cancers. Patients were eligible for the biliary tract cancer cohort if they were aged 18 years or older, had BRAFV600E-mutated, unresectable, metastatic, locally advanced, or recurrent biliary tract cancer, an Eastern Cooperative Oncology Group performance status of 0-2, and had received previous systemic treatment. All patients were treated with oral dabrafenib 150 mg twice daily and oral trametinib 2 mg once daily until disease progression or intolerance of treatment. The primary endpoint was the overall response rate, which was determined by Response Evaluation Criteria in Solid Tumors version 1.1 in the intention-to-treat evaluable population, which comprised all enrolled patients regardless of receiving treatment who were evaluable (ie, had progression, began a new anticancer treatment, withdrew consent, died, had stable disease for 6 weeks or longer, or had two or more post-baseline assessments). The ROAR trial is registered with ClinicalTrials.gov, NCT02034110. These results are based on an interim analysis; the study is active but not recruiting. FINDINGS: Between March 12, 2014, and July 18, 2018, 43 patients with BRAFV600E-mutated biliary tract cancer were enrolled to the study and were evaluable. Median follow-up was 10 months (IQR 6-15). An investigator-assessed overall response was achieved by 22 (51%, 95% CI 36-67) of 43 patients. An independent reviewer-assessed overall response was achieved by 20 (47%, 95% CI 31-62) of 43 patients. The most common grade 3 or worse adverse event was increased γ-glutamyltransferase in five (12%) patients. 17 (40%) patients had serious adverse events and nine (21%) had treatment-related serious adverse events, the most frequent of which was pyrexia (eight [19%]). No treatment-related deaths were reported. INTERPRETATION: Dabrafenib plus trametinib combination treatment showed promising activity in patients with BRAFV600E-mutated biliary tract cancer, with a manageable safety profile. Routine testing for BRAFV600E mutations should be considered in patients with biliary tract cancer. FUNDING: GlaxoSmithKline and Novartis.


Assuntos
Neoplasias do Sistema Biliar/tratamento farmacológico , Imidazóis/administração & dosagem , Oximas/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Biliar/genética , Neoplasias do Sistema Biliar/patologia , Intervalo Livre de Doença , Feminino , Humanos , Imidazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Oximas/efeitos adversos , Piridonas/efeitos adversos , Pirimidinonas/efeitos adversos , Resultado do Tratamento
6.
PLoS One ; 15(8): e0236580, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756609

RESUMO

Lung cancer is generally treated with conventional therapies, including chemotherapy and radiation. These methods, however, are not specific to cancer cells and instead attack every cell present, including normal cells. Personalized therapies provide more efficient treatment options as they target the individual's genetic makeup. The goal of this study was to identify the frequency of causal genetic mutations across a variety of lung cancer subtypes in the earlier stages. 833 samples of non-small cell lung cancer from 799 patients who received resection of their lung cancer, were selected for molecular analysis of six known mutations, including EGFR, KRAS, BRAF, PIK3CA, HER2 and ALK. A SNaPshot assay was used for point mutations and fragment analysis searched for insertions and deletions. ALK was evaluated by IHC +/- FISH. Statistical analysis was performed to determine correlations between molecular and clinical/pathological patient data. None of the tested variants were identified in most (66.15%) of cases. The observed frequencies among the total samples vs. only the adenocarcinoma cases were notable different, with the highest frequency being the KRAS mutation (24.49% vs. 35.55%), followed by EGFR (6.96% vs. 10.23%), PIK3CA (1.20% vs. 0.9%), BRAF (1.08% vs. 1.62%), ALK (0.12% vs. 0.18%), while the lowest was the HER2 mutation (0% for both). The statistical analysis yielded correlations between presence of a mutation with gender, cancer type, vascular invasion and smoking history. The outcome of this study will provide data that helps stratify patient prognosis and supports development of more precise treatments, resulting in improved outcomes for future lung cancer patients.


Assuntos
Adenocarcinoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Predisposição Genética para Doença , Prognóstico , Adenocarcinoma/classificação , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico/genética , Carcinoma Pulmonar de Células não Pequenas/classificação , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Receptores ErbB/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor ErbB-2/genética
7.
Croat Med J ; 61(3): 271-275, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32643344

RESUMO

Ameloblastic carcinoma (AC) is a rare and aggressive malignant epithelial odontogenic tumor, most commonly located in the mandible or maxilla. An extremely rare extragnathic localization of AC with no connection to the jaws, ectopic ameloblastic carcinoma (EAC), has so far been described only three times. This report presents a 64-year-old male with skull base ameloblastic carcinoma and offers a review of diagnostic and treatment challenges related to EAC. Because of its rarity and histological similarity to other tumors, EAC is often misdiagnosed. This is why we established a pathohistological and immunohistochemical profile of EAC that differentiates it from histologically similar tumors. The most frequently used EAC treatment is radical surgical resection, but the majority of reviewed reports described local recurrence. Taking into consideration new scientific discoveries on the molecular pathogenesis of ameloblastoma, we are the first to have performed BRAF mutation analysis in an EAC patient. BRAF inhibitors offer promising results in the treatment of BRAF-positive ameloblastomas and should continue to be researched in AC and EAC patients. Finally, EAC should be considered in differential diagnosis of head and neck tumors outside the jaws.


Assuntos
Ameloblastoma/diagnóstico por imagem , Coristoma/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico , Tumores Odontogênicos/diagnóstico por imagem , Neoplasias dos Seios Paranasais , Ameloblastoma/genética , Ameloblastoma/cirurgia , Coristoma/genética , Coristoma/cirurgia , Análise Mutacional de DNA , Evolução Fatal , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cavidade Nasal , Tumores Odontogênicos/genética , Tumores Odontogênicos/cirurgia , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas B-raf/genética , Tomografia Computadorizada por Raios X
8.
PLoS One ; 15(7): e0235490, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628708

RESUMO

Mutations in KRAS, NRAS, and BRAF (RAS/BRAF) genes are the main predictive biomarkers for the response to anti-EGFR monoclonal antibodies (MAbs) targeted therapy in metastatic colorectal cancer (mCRC). This retrospective study aimed to report the mutational status prevalence of these genes, explore their possible associations with clinicopathological features, and build and validate a predictive model. To achieve these objectives, 500 mCRC Mexican patients were screened for clinically relevant mutations in RAS/BRAF genes. Fifty-two percent of these specimens harbored clinically relevant mutations in at least one screened gene. Among these, 86% had a mutation in KRAS, 7% in NRAS, 6% in BRAF, and 2% in both NRAS and BRAF. Only tumor location in the proximal colon exhibited a significant correlation with KRAS and BRAF mutational status (p-value = 0.0414 and 0.0065, respectively). Further t-SNE analyses were made to 191 specimens to reveal patterns among patients with clinical parameters and KRAS mutational status. Then, directed by the results from classical statistical tests and t-SNE analysis, neural network models utilized entity embeddings to learn patterns and build predictive models using a minimal number of trainable parameters. This study could be the first step in the prediction for RAS/BRAF mutational status from tumoral features and could lead the way to a more detailed and more diverse dataset that could benefit from machine learning methods.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , GTP Fosfo-Hidrolases/genética , Proteínas de Membrana/genética , Modelos Estatísticos , Taxa de Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Estudos de Coortes , Neoplasias Colorretais/epidemiologia , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Redes Neurais de Computação , Estudos Retrospectivos
9.
Tumour Biol ; 42(7): 1010428320938492, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32635826

RESUMO

Molecular classification of colorectal cancer is difficult to implement in clinical settings where hundreds of genes are involved, and resources are limited. This study aims to characterize the molecular subtypes of patients with sporadic colorectal cancer based on the three main carcinogenic pathways microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and chromosomal instability (CIN) in a Chilean population. Although several reports have characterized colorectal cancer, most do not represent Latin-American populations. Our study includes 103 colorectal cancer patients who underwent surgery, without neoadjuvant treatment, in a private hospital between 2008 and 2017. MSI, CIN, and CIMP status were assessed. Frequent mutations in KRAS, BRAF, and PIK3CA genes were analyzed by Sanger sequencing, and statistical analysis was performed by Fisher's exact and/or chi-square test. Survival curves were estimated with Kaplan-Meier and log-rank test. Based on our observations, we can classify the tumors in four subgroups, Group 1: MSI-high tumors (15%) are located in the right colon, occur at older age, and 60% show a BRAF mutation; Group 2: CIN-high tumors (38%) are in the left colon, and 26% have KRAS mutations. Group 3: [MSI/CIN/CIMP]-low/negative tumors (30%) are left-sided, and 39% have KRAS mutations; Group 4: CIMP-high tumors (15%) were more frequent in men and left side colon, with 27% KRAS and 7% presented BRAF mutations. Three percent of patients could not be classified. We found that CIMP-high was associated with a worse prognosis, both in MSI-high and MSI stable patients (p = 0.0452). Group 3 (Low/negative tumors) tend to have better overall survival compared with MSI-high, CIMP-high, and CIN-high tumors. This study contributes to understanding the heterogeneity of tumors in the Chilean population being one of the few characterizations performed in Latin-America. Given the limited resources of these countries, these results allow to improve molecular characterization in Latin-American colorectal cancer populations and confirm the possibility of using the three main carcinogenic pathways to define therapeutic strategies.


Assuntos
Carcinogênese/genética , Instabilidade Cromossômica/genética , Neoplasias Colorretais/genética , Instabilidade de Microssatélites , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Chile/epidemiologia , Neoplasias Colorretais/classificação , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Ilhas de CpG/genética , Metilação de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
10.
Am Surg ; 86(5): 450-457, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32684022

RESUMO

This study analyzed the characteristics of BRAFV600E mutation in papillary thyroid carcinoma (PTC) in Chinese coastal areas. We intended to identify noninvasive methods to determine BRAFV600E status in thyroid nodules prior to surgery. BRAFV600E mutation and the sonographic characteristics of thyroid nodules were investigated in 670 PTC patients in our hospital. We aimed to determine the relationship between BRAFV600E mutation and the clinicopathological and sonographic imaging characteristics of PTC. The mutation rate of the BRAFV600E was 78.2%. BRAFV600E mutation was significantly associated with central node (univariate analyses, P = .005; multivariate analyses, P < .001, odds ratio [OR] = 10.255) and lateral node metastases (univariate analyses, P = .001; multivariate analyses, P < .001, OR = 22). It was less frequent in PTC coexisting with Hashimoto's thyroiditis (univariate analyses, P = .016; multivariate analyses, P < .001, OR = .034). Nodules without blood flow had a significantly higher mutation rate of BRAFV600E in PTC patients (univariate analyses, P = .026). BRAFV600E mutation was significantly associated with high suspicion in the Thyroid Imaging Reporting and Data System 5 (univariate analyses, P = .004; multivariate analyses, P = .014, OR = 6.456). Our results strongly suggest that BRAFV600E mutation plays a potential role in lymph node metastasis (central node metastasis, OR = 10.225; lateral node metastasis, OR = 22). Some sonographic imaging features might be helpful in estimating the status of BRAFV600E preoperatively.


Assuntos
Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/diagnóstico por imagem , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/genética , Adulto , China , Correlação de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
11.
Proc Natl Acad Sci U S A ; 117(32): 19435-19445, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32719131

RESUMO

The Ras/RAF/MEK/ERK pathway is an essential signaling cascade for various refractory cancers, such as those with mutant KRAS (mKRAS) and BRAF (mBRAF). However, there are unsolved ambiguities underlying mechanisms for this growth signaling thereby creating therapeutic complications. This study shows that a vital component of the pathway CRAF is directly impacted by an end product of the cascade, glutathione transferases (GST) P1 (GSTP1), driving a previously unrecognized autocrine cycle that sustains proliferation of mKRAS and mBRAF cancer cells, independent of oncogenic stimuli. The CRAF interaction with GSTP1 occurs at its N-terminal regulatory domain, CR1 motif, resulting in its stabilization, enhanced dimerization, and augmented catalytic activity. Consistent with the autocrine cycle scheme, silencing GSTP1 brought about significant suppression of proliferation of mKRAS and mBRAF cells in vitro and suppressed tumorigenesis of the xenografted mKRAS tumor in vivo. GSTP1 knockout mice showed significantly impaired carcinogenesis of mKRAS colon cancer. Consequently, hindering the autocrine loop by targeting CRAF/GSTP1 interactions should provide innovative therapeutic modalities for these cancers.


Assuntos
Glutationa S-Transferase pi/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Animais , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Glutationa S-Transferase pi/antagonistas & inibidores , Glutationa S-Transferase pi/deficiência , Glutationa S-Transferase pi/genética , Humanos , Camundongos , Camundongos Knockout , Mutação , Neoplasias/genética , Neoplasias/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas/genética , Multimerização Proteica , Estabilidade Proteica , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-raf/química , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais
12.
Bull Cancer ; 107(9): 881-895, 2020 Sep.
Artigo em Francês | MEDLINE | ID: mdl-32674932

RESUMO

The BRAFV600E mutation, observed in 8 % of colorectal cancers (CRC), introduces a particular phenotype and a poor prognosis at the localized or metastatic stage. BRAF mutant CRCs are more often localized in the right colon, poorly differentiated and mucinous. They affect an older population (more often female) and are associated with a more frequent metastatic lymph node and peritoneal evolution. The BRAFV600E mutation is associated with a sporadic microsatellite instability (MSI) status in 20 to 40% of cases. In localized colon cancer, it does not imply any modification of the adjuvant treatment. In metastatic CRC, the first action must be the systematic search for an MSI phenotype, given its frequent association with the presence of a BRAF mutation, in order to propose immunotherapy that has been demonstrated to be very effective in MSI metastatic CRC. In non-MSI CRC, a first-line trichimiotherapy associated with bevacizumab is an option to be favored in patients in good general condition but the association with an anti-EGFR can be discussed, especially when the objective is tumor response. At the same time, surgical resection must be systematically discussed in the case of resectable hepatic metastases since the presence of a BRAFV600E mutation is not a risk factor for recurrence and that prolonged survival may be observed after surgery. In the second or third line, the triplet encorafenib, binimetinib and cetuximab, as well as the doublet encorafenib and cetuximab are superior to the association of irinotecan plus cetuximab in terms of response and survival (phase III study BEACON) and represent a new therapeutic standard. Their use on the front line is under study.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Árvores de Decisões , Humanos
13.
Zhonghua Zhong Liu Za Zhi ; 42(6): 463-468, 2020 Jun 23.
Artigo em Chinês | MEDLINE | ID: mdl-32575941

RESUMO

Objective: To explore the differential protein expressions in papillary thyroid carcinoma (PTC) with or without Hashimoto's thyroiditis (HT). Methods: Tissue microarray was prepared and the protein expression levels of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), vascular endothelial growth factor (VEGF), cyclinD1, mesothelial cell (MC) , CD56 and Galectin3 in the PTC tissues with or without HT were detected by immunohistochemical staining. Results: The positive expression rates of BRAF protein in the PTC tissues with or without HT groups were 55.4% (36/65) and 63.6% (42/66), respectively, without significant difference (P=0.336). The positive expression rates of VEGF protein in the PTC tissues with or without HT groups were 25.7% (19/74) and 25.8%(17/66), respectively, without significant difference (P=0.991). The positive expression rates of cyclin D1 protein in the PTC tissues with or without HT groups were 93.4% (71/76) and 97.6% (80/82), without significant difference (P=0.206). The positive expression rates of MC protein in the PTC tissues with or without HT groups were 86.1% (62/72) and 83.5%(71/85), without significant difference (P=0.654). The positive expression rates of Galectin3 protein in the PTC tissues with or without HT groups were 98.7% (76/77) and 97.5% (78/80), without significant difference (P=0.583). The positive expression rates of CD56 in the PTC tissues and adjacent thyroid follicular epithelial cells were 27.4% (32/117) and 65.0% (76/117), respectively, and the difference was statistically significant (P=0.001). The positive expression rates of CD56 in PTC tissues with or without HT were 35.5% (24/68) and 16.5% (13/79), respectively, and the difference was statistically significant (P=0.009). Conclusions: There are no significant differences in the expressions of BRAF, VEGF, CyclinD1, MC and Galectin3 between the PTC tissues with or without HT. However, the significantly differential expression of CD56 between the two group suggests that CD56 may be related to the pathogenesis of PTC with HT. CD56 may be used as a potential molecular marker in PTC diagnosis.


Assuntos
Adenocarcinoma Papilar/genética , Antígeno CD56/metabolismo , Carcinoma Papilar/patologia , Doença de Hashimoto/genética , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adenocarcinoma Papilar/metabolismo , Adenocarcinoma Papilar/patologia , Animais , Biomarcadores/análise , Carcinoma Papilar/metabolismo , Ciclina D1/genética , Galectinas , Doença de Hashimoto/metabolismo , Doença de Hashimoto/patologia , Humanos , Camundongos , Valor Preditivo dos Testes , Proteínas Proto-Oncogênicas B-raf/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/patologia , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Análise Serial de Tecidos , Fator A de Crescimento do Endotélio Vascular/genética
14.
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
15.
Gan To Kagaku Ryoho ; 47(6): 861-869, 2020 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-32541157

RESUMO

In Japan, clinically, a decade has passed since KRAS exon 2 hotspot mutations could be measured as a companion diagnostic agent of an anti-epidermal growth factor receptor antibody to treat unresectable advanced colorectal cancer. Till now, not only KRAS exon 2, but also KRAS exon 3, 4 and NRAS exon 2-4 mutation, and BRAF mutation(V600E)are approved as insurance as a companion diagnostics tool. In addition to those somatic mutations observed in Ras-Raf signal cascade, the measurement of microsatellite instability status is also approved as a companion diagnostic to anti-programmed death-1 receptor antibodies. Since these somatic mutational profiles in colorectal cancer cells are measured to determine the propriety of administration of a particular medicine, the results must be appropriately reflected in therapy for each patient. In this review, I will summarize the feature of clinical characteristics belonging to each somatic mutational profile commonly observed in colorectal cancer, and discuss howsuch somatic mutational profiles including RAS, BRAF mutation, and microsatellite instability status bring us to a newera of colorectal cancer.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Colorretais/genética , Humanos , Japão , Instabilidade de Microssatélites , Mutação
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.
APMIS ; 128(9): 515-522, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32580246

RESUMO

Peripheral nerve sheath tumors may occur sporadically or related to neurofibromatosis (NF). Unless the mechanisms of tumorigenesis in NF related malignant peripheral nerve sheath tumors (MPNST) are better understood, it remained unclear in sporadic cases. We aimed to investigate the genetic route for malignancy in both individuals with NF-1 and sporadic ones to open a way for targeted therapies in the future. We investigated the role of HER2 with Dual ISH DNA Probe Cocktail test, BRAF mutation (exon 15) and TERT promoter mutation frequency with Sanger sequencing method in respectively 25 sporadic neurofibromas, 25 NF-1 related neurofibromas and 25 MPNST cases from two institutes. Categorical data were analyzed and summarized as frequency and percentage. Statistical analysis was done with SPSS v.22 statistical package, and the statistical significance level was considered as 0.05. We identified TERT promoter mutation only in one sporadic MPNST (4%) and no BRAF mutation in any case. HER2 amplification is found in 10/25 (40%) MPNST cases. No mutations or gene amplification detected in neurofibromas (p < 0.001). MPNSTs are sarcomas with poor prognosis and limited treatment options. TERT promoter mutations and HER2 amplification may play a putative role in therapeutic purposes.


Assuntos
Neurofibromatose 1/genética , Neurofibrossarcoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Receptor ErbB-2/genética , Telomerase/genética , Adolescente , Adulto , Idoso , Criança , Feminino , Amplificação de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neurofibroma/genética , Regiões Promotoras Genéticas , Adulto Jovem
19.
Proc Natl Acad Sci U S A ; 117(27): 15846-15851, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32561648

RESUMO

Combination use of BRAF V600E inhibitor dabrafenib and MEK inhibitor trametinib has become a standard treatment for human cancers harboring BRAF V600E. Its anticancer efficacies vary, however, with dramatic efficacy in some patients and drug resistance/tumor recurrence in others, which is poorly understood. Using thyroid cancer, melanoma, and colon cancer cell models, we showed that dabrafenib and trametinib induced robust apoptosis of cancer cells harboring both BRAF V600E and TERT promoter mutations but had little proapoptotic effect in cells harboring only BRAF V600E. Correspondingly, the inhibitors nearly completely abolished the growth of in vivo tumors harboring both mutations but had little effect on tumors harboring only BRAF V600E. Upon drug withdrawal, tumors harboring both mutations remained hardly measurable but tumors harboring only BRAF V600E regrew rapidly. BRAF V600E/MAP kinase pathway is known to robustly activate mutant promoter of TERT, a strong apoptosis suppressor. Thus, for survival, cancer cells harboring both mutations may have evolved to rely on BRAF V600E-promoted and high-TERT expression-mediated suppression of apoptosis. As such, inhibition of BRAF/MEK can trigger strong apoptosis-induced cell death and hence tumor abolishment. This does not happen in cells harboring only BRAF V600E as they have not developed reliance on TERT-mediated suppression of apoptosis due to the lack of mutant promoter-driven high-TERT expression. TERT promoter mutation governs BRAF-mutant cancer cells' apoptotic and hence therapeutic responses to BRAF/MEK inhibitors. Thus, the genetic duet of BRAF V600E and TERT promoter mutation represents an Achilles Heel for effective therapeutic targeting and response prediction in cancer.


Assuntos
Apoptose/efeitos dos fármacos , Mutação , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/efeitos dos fármacos , Proteínas Proto-Oncogênicas B-raf/genética , Telomerase/genética , Animais , Morte Celular , Linhagem Celular Tumoral , Neoplasias do Colo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Imidazóis/farmacologia , Melanoma/genética , Camundongos Nus , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oximas/farmacologia , Piridonas/farmacologia , Pirimidinonas/farmacologia , Neoplasias da Glândula Tireoide/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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