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1.
Medicine (Baltimore) ; 99(39): e22322, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32991441

RESUMO

RATIONALE: Bronchiolar adenoma (BA) is a newly designated rare entity of the lung, including both the currently designated ciliated muconodular papillary tumor (CMPT) and so-called non-classic CMPT. The most prominent histological feature of BAs is the bilayered cell structures composed of the continuous basal cell layer and the luminal layer which consists of different proportion of mucinous cells, ciliated cells, Clara cells and/or type II pneumocytes. BA purely covered by mucinous cells without other components in the luminal layer has never been reported. PATIENT CONCERNS: An 82-year-old female patient was detected a 0.8 cm ground glass nodule in the left lower lobe of the lung. DIAGNOSES: The serum levels of tumor markers were normal. INTERVENTIONS: The patient underwent a segmentectomy of the left lower lobe. OUTCOMES: The postoperative pathological diagnosis was BA. Molecular analysis revealed that the tumor harbored ALK rearrangement and BRAF mutations simultaneously. There was no recurrence in 17 months of follow-up. LESSONS: BA can be lined only by mucinous cells, without any cuboidal and/or ciliated cells in the surface layer. This sets a dangerous pitfall in differentiation diagnosis with invasive mucinous adenocarcinoma especially during intraoperative frozen pathological diagnosis.


Assuntos
Adenoma/metabolismo , Bronquíolos/patologia , Neoplasias Pulmonares/patologia , Biologia Molecular/métodos , Adenoma/cirurgia , Assistência ao Convalescente , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico/metabolismo , Biomarcadores Tumorais/sangue , Feminino , Humanos , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Pneumonectomia/métodos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Resultado do Tratamento
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.
Nat Commun ; 11(1): 4015, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782246

RESUMO

Intracellular pathogens mobilize host signaling pathways of their host cell to promote their own survival. Evidence is emerging that signal transduction elements are activated in a-nucleated erythrocytes in response to infection with malaria parasites, but the extent of this phenomenon remains unknown. Here, we fill this knowledge gap through a comprehensive and dynamic assessment of host erythrocyte signaling during infection with Plasmodium falciparum. We used arrays of 878 antibodies directed against human signaling proteins to interrogate the activation status of host erythrocyte phospho-signaling pathways at three blood stages of parasite asexual development. This analysis reveals a dynamic modulation of many host signalling proteins across parasite development. Here we focus on the hepatocyte growth factor receptor (c-MET) and the MAP kinase pathway component B-Raf, providing a proof of concept that human signaling kinases identified as activated by malaria infection represent attractive targets for antimalarial intervention.


Assuntos
Antimaláricos/farmacologia , Eritrócitos/metabolismo , Plasmodium falciparum/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Eritrócitos/parasitologia , Interações Hospedeiro-Parasita , Humanos , Concentração Inibidora 50 , Estágios do Ciclo de Vida/efeitos dos fármacos , Malária Falciparum/metabolismo , Malária Falciparum/parasitologia , Fosforilação/efeitos dos fármacos , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Plasmodium falciparum/fisiologia , Análise Serial de Proteínas , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
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
6.
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
7.
Arch Cardiovasc Dis ; 113(6-7): 420-432, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32418884

RESUMO

BACKGROUND: The risk of cardiovascular adverse events from rapidly accelerated fibrosarcoma B-type (BRAF) and mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors is not fully characterized. AIM: To evaluate the cardiovascular adverse events risks related to BRAF and/or MEK inhibitors in randomized placebo-controlled clinical trials and in the real-life setting. METHODS: We used two approaches. First, we conducted a systematic review and meta-analysis of randomized placebo-controlled clinical trials reporting the incidence of cardiovascular adverse events for BRAF and/or MEK inhibitors in cancer patients. Second, we performed a disproportionality analysis, using age- and sex-adjusted reporting odds ratios (arORs) and their 95% confidence intervals (CIs) from the World Health Organization's pharmacovigilance database (VigiBase®) of anticancer drug-associated reports, to investigate real-life data. RESULTS: MEK inhibitors increased the risk of ejection fraction decrease (odds ratio [OR] 3.35, 95% CI 1.58-7.07), peripheral oedema (OR 2.87 95% CI 1.93-4.27) and syncope (OR 6.71, 95% CI 3.00-14.99) compared with placebo in randomized placebo-controlled clinical trials. BRAF and MEK inhibitor combination therapy further increased the risk of ejection fraction decrease. In the disproportionality analysis, we found over-reporting of ejection fraction decrease (arOR 8.42, 95% CI 7.03-10.09), peripheral oedema (arOR 1.39, 95% CI 1.17-1.66), syncope (arOR 1.56, 95% CI 1.22-1.99), torsade de pointes/QT prolongation (arOR 6.13, 95% CI 5.04-7.47) and supraventricular arrhythmias (arOR 1.50, 95% CI 1.21-1.85) for BRAF and MEK inhibitors. BRAF and MEK inhibitors were not associated with hypertension in either approach. CONCLUSIONS: In conclusion, MEK inhibitors increase the risk of ejection fraction decrease, peripheral oedema and syncope in randomized placebo-controlled clinical trials. Real-life data confirm these findings, and suggested additional risks of torsade de pointes/QT prolongation and supraventricular arrhythmias with BRAF/MEK inhibitors.


Assuntos
Antineoplásicos/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Fibrossarcoma/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Bases de Dados Factuais , Feminino , Fibrossarcoma/enzimologia , Fibrossarcoma/epidemiologia , Fibrossarcoma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Segurança do Paciente , Farmacovigilância , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Resultado do Tratamento
8.
J Med Chem ; 63(8): 4069-4080, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32223235

RESUMO

BRAF is among the most frequently mutated oncogenes in human cancers. Multiple small molecule BRAF kinase inhibitors have been approved for treating melanoma carrying BRAF-V600 mutations. However, the benefits of BRAF kinase inhibitors are generally short-lived. Small molecule-mediated targeted protein degradation has recently emerged as a novel pharmaceutical strategy to remove disease proteins through hijacking the cellular ubiquitin proteasome system (UPS). In this study, we developed thalidomide-based heterobifunctional compounds that induced selective degradation of BRAF-V600E, but not the wild-type BRAF. Downregulation of BRAF-V600E suppressed the MEK/ERK kinase cascade in melanoma cells and impaired cell growth in culture. Abolishing the interaction between degraders and cereblon or blocking the UPS significantly impaired the activities of these degraders, validating a mechanistic role of UPS in mediating targeted degradation of BRAF-V600E. These findings highlight a new approach to modulate the functions of oncogenic BRAF mutants and provide a framework to treat BRAF-dependent human cancers.


Assuntos
Descoberta de Drogas/métodos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Vemurafenib/química , Vemurafenib/metabolismo , Vemurafenib/farmacologia
9.
Chem Biol Interact ; 323: 109061, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32194039

RESUMO

Oncogenic alterations in the BRAF gene are identified in an estimate of 50% of melanomas and cause melanoma development. BRAF kinase inhibitors (BRAFi), including vemurafenib and dabrafenib, were discovered and used in the clinical treatment of BRAF-mutant metastatic melanoma. Though, BRAFi's therapeutic advantages are short term and short-lived associated with drug resistance. Although a few pathways of developed BRAFi resistance have also been established, in approximately 40% of melanomas, the cause for inherited resistance remains unclear. Recognizing a new process of developed BRAFi resistance might provide new possibilities to successfully treat BRAF mutant melanoma. In this study, we are exploring the compensatory alternative pathway followed by BRAFi/MEKi treated resistant cell for maintaining the long-term integrity and survival.


Assuntos
Citoproteção , Resistencia a Medicamentos Antineoplásicos , Melanoma/patologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Transdução de Sinais , Neoplasias Cutâneas/patologia , Humanos , Proteínas Proto-Oncogênicas B-raf/metabolismo
10.
Biochemistry (Mosc) ; 85(1): 108-118, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32079522

RESUMO

The MAPK (RAS/BRAF/MEK/ERK) signaling pathway is a kinase cascade involved in the regulation of cell proliferation, differentiation, and survival in response to external stimuli. The V600E mutation in the BRAF gene has been detected in various tumors, resulting in a 500-fold increase in BRAF kinase activity. However, monotherapy with selective BRAF V600E inhibitors often leads to reactivation of MAPK signaling cascade and emergence of drug resistance. Therefore, new targets are being developed for the inhibition of components of the aberrantly activated cascade. It was recently discovered that resistance to BRAF V600E inhibitors may be associated with the activity of the tyrosine phosphatase SHP-2 encoded by the PTPN11 gene. In this paper, we analyzed transcriptional effects of PTPN11 gene knockdown and selective suppression of BRAF V600E in a model of thyroid follicular epithelium. We found that the siRNA-mediated knockdown of PTPN11 after vemurafenib treatment prevented an increase in the expression CCNA1 and NOTCH4 genes involved in the formation of drug resistance of tumors. On the other hand, downregulation of PTPN11 expression blocked the transcriptional activation of genes (p21, p15, p16, RB1, and IGFBP7) involved in cell cycle regulation and oncogene-induced senescence in response to BRAF V600E expression. Therefore, it can be assumed that SHP-2 participates not only in emergence of drug resistance in cancer cells, but also in oncogene-induced cell senescence.


Assuntos
Proteína Tirosina Fosfatase não Receptora Tipo 11/fisiologia , Proteínas Proto-Oncogênicas B-raf/metabolismo , Células Epiteliais da Tireoide , Neoplasias da Glândula Tireoide/metabolismo , Ciclo Celular , Linhagem Celular , Senescência Celular , Resistencia a Medicamentos Antineoplásicos/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Células Epiteliais da Tireoide/citologia , Células Epiteliais da Tireoide/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Vemurafenib/uso terapêutico
11.
PLoS One ; 15(2): e0228968, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053670

RESUMO

PURPOSE: To evaluate whether if ultrasonography (US)-based radiomics enables prediction of the presence of BRAFV600E mutations among patients diagnosed as papillary thyroid carcninoma (PTC). METHODS: From December 2015 to May 2017, 527 patients who had been treated surgically for PTC were included (training: 387, validation: 140). All patients had BRAFV600E mutation analysis performed on surgical specimen. Feature extraction was performed using preoperative US images of the 527 patients (mean size of PTC: 16.4mm±7.9, range, 10-85 mm). A Radiomics Score was generated by using the least absolute shrinkage and selection operator (LASSO) regression model. Univariable/multivariable logistic regression analysis was performed to evaluate the factors including Radiomics Score in predicting BRAFV600E mutation. Subgroup analysis including conventional PTC <20-mm (n = 389) was performed (training: 280, validation: 109). RESULTS: Of the 527 patients diagnosed with PTC, 428 (81.2%) were positive and 99 (18.8%) were negative for BRAFV600E mutation. In both total 527 cancers and 389 conventional PTC<20-mm, Radiomics Score was the single factor showing significant association to the presence of BRAFV600E mutation on multivariable analysis (all P<0.05). C-statistics for the validation set in the total cancers and the conventional PTCs<20-mm were lower than that of the training set: 0.629 (95% CI: 0.516-0.742) to 0.718 (95% CI: 0.650-0.786), and 0.567 (95% CI: 0.434-0.699) to 0.729 (95% CI: 0.632-0.826), respectively. CONCLUSION: Radiomics features extracted from US has limited value as a non-invasive biomarker for predicting the presence of BRAFV600E mutation status of PTC regardless of size.


Assuntos
Câncer Papilífero da Tireoide/diagnóstico por imagem , Câncer Papilífero da Tireoide/genética , Ultrassonografia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/patologia , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Dados Preliminares , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Radiografia/métodos , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
13.
Nat Struct Mol Biol ; 27(2): 134-141, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31988522

RESUMO

The RAS-RAF-MEK-ERK signaling axis is frequently activated in human cancers. Physiological concentrations of ATP prevent formation of RAF kinase-domain (RAFKD) dimers that are critical for activity. Here we present a 2.9-Å-resolution crystal structure of human BRAFKD in complex with MEK and the ATP analog AMP-PCP, revealing interactions between BRAF and ATP that induce an inactive, monomeric conformation of BRAFKD. We also determine how 14-3-3 relieves the negative regulatory effect of ATP through a 2.5-Å-resolution crystal structure of the BRAFKD-14-3-3 complex, in which dimeric 14-3-3 enforces a dimeric BRAFKD assembly to increase BRAF activity. Our data suggest that most oncogenic BRAF mutations alter interactions with ATP and counteract the negative effects of ATP binding by lowering the threshold for RAF dimerization and pathway activation. Our study establishes a framework for rationalizing oncogenic BRAF mutations and provides new avenues for improved RAF-inhibitor discovery.


Assuntos
Proteínas 14-3-3/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas 14-3-3/química , Trifosfato de Adenosina/análogos & derivados , Proteínas Mutadas de Ataxia Telangiectasia/química , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Cristalografia por Raios X , Humanos , Simulação de Dinâmica Molecular , Conformação Proteica , Multimerização Proteica , Proteínas Proto-Oncogênicas B-raf/química
14.
Dis Markers ; 2020: 8459303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998419

RESUMO

Pathologic features depending on tumor response to preoperative chemoradiotherapy are important to determine the outcomes in patients with rectal cancer. Evaluating the potential predictive roles of biomarker expression and their prognostic impact is a promising challenge. We reported here the immunohistochemical staining of a panel marker of mismatch repair protein (MMR), Ki67, HER-2, and p53. Additionally, identification of somatic mutations of KRAS, NRAS, and BRAF genes were performed by direct sequencing and pyrosequencing in pretreated biopsy tissues from 57 patients diagnosed for rectal cancer. Clinical features and pathological criteria for postneoadjuvant treatment surgical resection specimen's data were collected. Immunohistochemical expression and mutational status were correlated with therapeutic response, overall survival, and disease progression. The mean age of patients was 56 years. Seven (12.3%) out of 57 patients had a complete therapeutic response. Our analysis showed that when using complete therapeutic response (Dworak 4) and incomplete therapeutic response (Dworak 3, 2, and 1) as grouping factor, high p53 expression at the pretreatment biopsy was significantly associated to an incomplete response (p = 0.002). For 20 and 2 out of 57, KRAS and NRAS mutations were detected, respectively. The majority of these mutations affected codon 12. KRAS mutations detected at codon 146 (A146T, A146V) was associated with the appearance of recurrence and distant metastasis (p = 0.019). A high expression of HER-2 corresponding to score 3+ was observed in 3 pretreatment biopsy specimens. This class was significantly associated with a short relapse-free survival (p = 0.002). Furthermore, the high expression of Ki67 was moderately correlated with an older age (p = 0.016, r = 0.319). In addition, this shows that high p53 expression in the pretreatment biopsy was associated with an incomplete response in surgical resection specimens after neoadjuvant treatment, and a HER-2 score 3+ can be a predictive factor of distant metastasis and local recurrence. Larger, prospective, and more studies are needed.


Assuntos
Carcinoma/genética , Terapia Neoadjuvante , Neoplasias Retais/genética , Adulto , Idoso , Carcinoma/metabolismo , Carcinoma/patologia , Carcinoma/terapia , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Eur J Med Chem ; 186: 111885, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31784187

RESUMO

Constitutive activation of STAT3 can play a vital role in the development of melanoma. STAT3-targeted therapeutics are reported to show efficacy in melanomas harboring the BRAFV600E mutant and also in vemurafenib-resistant melanomas. We designed and synthesized a series of substituted nitric oxide (NO)-releasing quinolone-1,2,4-triazole/oxime hybrids, hypothesizing that the introduction of a STAT3 binding scaffold would augment their cytotoxicity. All the hybrids tested showed a comparable level of in vitro NO production. 7b and 7c exhibited direct binding to the STAT3-SH domain with IC50 of ∼ 0.5 µM. Also, they abrogated STAT3 tyrosine phosphorylation in several cancer cell lines, including the A375 melanoma cell line that carries the BRAFV600E mutation. At the same time, they did not affect the phosphorylation of upstream kinases or other STAT isoforms. 7c inhibited STAT3 nuclear translocation in mouse embryonic fibroblast while 7b and 7c inhibited STAT3 DNA-binding activity in the A375 cell line. Their anti-proliferating activity is attributed to their ability to trigger the production of reactive oxygen species and induce G1 cell cycle arrest in the A375 cell line. Interestingly, 7b and 7c showed robust cell growth suppression and apoptosis induction in two pairs of BRAF inhibitor-naïve (-S) and resistant (-R) melanoma cell lines containing a BRAF V600E mutation. Surprisingly, MEL1617-R cells that are known to be more resistance to MEK inhibition by GSK1120212 than MEL1617-S cells exhibit a similar response to 7b and 7c.


Assuntos
Antineoplásicos/farmacologia , Melanoma/tratamento farmacológico , Melanoma/patologia , Óxido Nítrico/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Fator de Transcrição STAT3/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Melanoma/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Óxido Nítrico/análise , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Fator de Transcrição STAT3/metabolismo , Relação Estrutura-Atividade
16.
Mol Cell ; 77(3): 633-644.e5, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-31836388

RESUMO

Metastatic melanoma is an aggressive disease, despite recent improvements in therapy. Eradicating all melanoma cells even in drug-sensitive tumors is unsuccessful in patients because a subset of cells can transition to a slow-cycling state, rendering them resistant to most targeted therapy. It is still unclear what pathways define these subpopulations and promote this resistant phenotype. In the current study, we show that Wnt5A, a non-canonical Wnt ligand that drives a metastatic, therapy-resistant phenotype, stabilizes the half-life of p53 and uses p53 to initiate a slow-cycling state following stress (DNA damage, targeted therapy, and aging). Inhibiting p53 blocks the slow-cycling phenotype and sensitizes melanoma cells to BRAF/MEK inhibition. In vivo, this can be accomplished with a single dose of p53 inhibitor at the commencement of BRAF/MEK inhibitor therapy. These data suggest that taking the paradoxical approach of inhibiting rather than activating wild-type p53 may sensitize previously resistant metastatic melanoma cells to therapy.


Assuntos
Melanoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Wnt-5a/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MAP Quinase Quinase Quinases/metabolismo , Melanoma/genética , Melanoma/patologia , Terapia de Alvo Molecular , Mutação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/fisiologia
18.
Ann Surg ; 271(1): 147-154, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-29995686

RESUMO

OBJECTIVE: To analyze clinical outcomes and prognostic variables of patients undergoing hepatic resection for BRAF mutant (BRAF-mut) colorectal liver metastases (CRLM). BACKGROUND: Outcomes following hepatectomy for BRAF-mut CRLM have not been well studied. METHODS: All patients who underwent hepatectomy for CRLM with complete resection and known BRAF status during 2001 to 2016 at 3 high-volume centers were analyzed. RESULTS: Of 4124 patients who underwent hepatectomy for CRLM, 1497 had complete resection and known BRAF status. Thirty-five (2%) patients were BRAF-mut, with 71% of V600E mutation. Compared with BRAF wild-type (BRAF-wt), BRAF-mut patients were older, more commonly presented with higher ASA scores, synchronous, multiple and smaller CRLM, underwent more major hepatectomies, but had less extrahepatic disease. Median overall survival (OS) was 81 months for BRAF-wt and 40 months for BRAF-mut patients (P < 0.001). Median recurrence-free survival (RFS) was 22 and 10 months for BRAF-wt and BRAF-mut patients (P < 0.001). For BRAF-mut, factors associated with worse OS were node-positive primary tumor, carcinoembryonic antigen (CEA) >200 µg/L, and clinical risk score (CRS) ≥4. Factors associated with worse RFS were node-positive primary tumor, ≥4 CRLM, and positive hepatic margin. V600E mutations were not associated with worse OS or RFS. A case-control matching analysis on prognostic clinicopathologic factors confirmed shorter OS (P < 0.001) and RFS (P < 0.001) in BRAF-mut. CONCLUSIONS: Patients with resectable BRAF-mut CRLM are rare among patients selected for surgery and more commonly present with multiple synchronous tumors. BRAF mutation is associated with worse prognosis; however, long-term survival is possible and associated with node-negative primary tumors, CEA ≤ 200 µg/L and CRS < 4.


Assuntos
Neoplasias Colorretais/genética , DNA de Neoplasias/genética , Hepatectomia/métodos , Neoplasias Hepáticas/secundário , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Proteínas Proto-Oncogênicas B-raf/metabolismo , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
Am J Clin Oncol ; 43(2): 139-145, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31764020

RESUMO

Gynecologic clear cell carcinoma is a rare histology, accounting for ~5% of all ovarian and endometrial cancers in the United States. Compared to other types of gynecologic cancer, they are generally less responsive to standard therapy and have an overall worse prognosis. In addition, mounting evidence suggests that the landscape of genetic and molecular abnormalities observed in these tumors is distinct from other cancers that arise from the same sites of origin. On a molecular level, these tumors characteristically display upregulation of the PI3K-AKT-mTOR and RAS-RAF-MAPK signaling axes, frequent loss of ARID1a, and overexpression of MDM2. Evidence also suggests that these tumors are more likely to express programmed death ligand 1 or demonstrate microsatellite instability than other gynecologic cancers. Despite these important differences, there has been relatively little investigation into histology-specific treatment of clear cell gynecologic cancers, representing an opportunity for new drug development. In this article, we review the unique genetic and molecular features of gynecologic clear cell cancers with an emphasis on potential therapeutic targets. The results of completed studies of treatment for clear cell carcinoma are also presented. We conclude with a discussion of ongoing clinical trials and potential avenues for future study.


Assuntos
Adenocarcinoma de Células Claras/genética , Neoplasias dos Genitais Femininos/genética , Adenocarcinoma de Células Claras/tratamento farmacológico , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patologia , Antineoplásicos Imunológicos/uso terapêutico , Variações do Número de Cópias de DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Neoplasias dos Genitais Femininos/tratamento farmacológico , Neoplasias dos Genitais Femininos/metabolismo , Neoplasias dos Genitais Femininos/patologia , Fator 1-beta Nuclear de Hepatócito/genética , Fator 1-beta Nuclear de Hepatócito/metabolismo , Humanos , Instabilidade de Microssatélites , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Terapia de Alvo Molecular , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Quinases raf/genética , Quinases raf/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo
20.
J Cutan Pathol ; 47(1): 12-16, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31449665

RESUMO

The association of syringocystadenoma papilliferum (SCAP) with verrucous carcinoma (VC) of the skin in the same lesion is a rare, but well-documented event. Although human papillomaviruses (HPV) have been proposed to have an etiologic role in the development of the verrucous proliferations associated with SCAP, most of the immunohistochemical and molecular studies have failed to show the presence of their genomic material in these lesions. We report a series of four cases of SCAP associated with VC in anogenital lesions. In two of the cases, we demonstrated the presence of the BRAF V600E mutation by polymerase chain reaction and immunohistochemistry, both in the glandular and in the squamous component. No HPV-related histopathologic changes were found, nor could the presence of viral DNA be showed.


Assuntos
Carcinoma Verrucoso , Mutação de Sentido Incorreto , Segunda Neoplasia Primária , Proteínas Proto-Oncogênicas B-raf , Neoplasias das Glândulas Sudoríparas , Adenomas Tubulares de Glândulas Sudoríparas , Idoso , Idoso de 80 Anos ou mais , Substituição de Aminoácidos , Carcinoma Verrucoso/genética , Carcinoma Verrucoso/metabolismo , Carcinoma Verrucoso/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/metabolismo , Segunda Neoplasia Primária/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias das Glândulas Sudoríparas/genética , Neoplasias das Glândulas Sudoríparas/metabolismo , Neoplasias das Glândulas Sudoríparas/patologia , Adenomas Tubulares de Glândulas Sudoríparas/genética , Adenomas Tubulares de Glândulas Sudoríparas/metabolismo , Adenomas Tubulares de Glândulas Sudoríparas/patologia
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