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1.
Anticancer Res ; 40(5): 2667-2673, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366411

RESUMO

BACKGROUND/AIM: The therapeutic strategy for patients with non-small-cell lung cancer (NSCLC) harboring the BRAF non-V600E mutation has not been established. LY3009120, a newly discovered pan-RAF inhibitor, has shown strong antitumor effects in cancers with various BRAF genotypes. This study investigated the antitumor effects of LY3009120 in NSCLC cells harboring the BRAF non-V600E mutation. MATERIALS AND METHODS: We examined the antitumor effects of LY3009120 by MTS assay and flow cytometry. We analyzed the expression status of proteins by western blot. The mouse xenograft models were used for the in vivo experiments. RESULTS: LY3009120 suppressed BRAF-related downstream pathway molecules and induced cleavage of poly ADP-ribose polymerase in all examined NSCLC cell lines. LY3009120 also inhibited in vivo tumor growth in NSCLC cells harboring the BRAF non-V600E mutation. CONCLUSION: LY3009120 is a potent therapeutic agent for patients with BRAF non-V600E mutant NSCLC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/genética , Mutação/genética , Oncogenes , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Pirimidinas/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Concentração Inibidora 50 , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Rev Med Liege ; 75(4): 213-217, 2020 Apr.
Artigo em Francês | MEDLINE | ID: mdl-32267108

RESUMO

We report the case of a 47-year-old woman with unexplained inflammatory syndrome and asthenia. Imaging findings show bilateral abnormalities of femurs and tibias, suggesting an Erdheim-Chester disease, which is confirmed by a bone marrow biopsy of the left femur. The BRAF V600E mutation is detected, allowing the administration of targeted therapies such as BRAF and MEK inhibitors that lead to the improvement of symptoms.


Assuntos
Doença de Erdheim-Chester , Biópsia , Doença de Erdheim-Chester/diagnóstico , Doença de Erdheim-Chester/genética , Doença de Erdheim-Chester/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/genética
3.
Zhonghua Bing Li Xue Za Zhi ; 49(3): 256-261, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32187898

RESUMO

Objective: To investigate the frequency and clinical significance of RAS mutation in thyroid tumors with follicular differentiation. Methods: The samples and clinical data of 207 patients with thyroid follicular-differentiated tumors were collected at Shunyi Region Hospital of Beijing from January 2000 to December 2017, including 60 cases of follicular variant of papillary thyroid carcinoma (FVPTC), 42 cases of classical papillary thyroid carcinoma (CPTC), 26 cases of follicular thyroid carcinoma (FTC), 40 cases of follicular adenoma (FTA) and 39 cases of adenomatoid hyperplasia. BRAF V600E mutations were detected using immunohistochemical staining. FVPTC was divided into BRAF-like (BRAF V600E mutant) and RAS-like (without BRAF V600E mutant). Real-time fluorescence quantitative polymerase chain reaction was used to detect the RAS mutation in RAS-like FVPTC, CPTC, FTC, FTA and adenomatoid hyperplasia. The genetic differences in RAS mutation and their correlation with clinicopathological features were analyzed. Results: The average age of patients with benign and malignant tumors in thyroid with follicular differentiation was 53.2 years and 47.7 years, respectively. In these patients, 42 were male and165 were female. Most of the tumors had a maximum diameter of less than 4 cm, and rarely spread to the surrounding tissues of thyroid and were at early stage (stages Ⅰ and Ⅱ). The diameter of tumors in FTC was significantly larger than that in RAS-like FVPTC and CPTC groups (P<0.01). Peripheral thyroid invasion was rare in the RAS-like FVPTC, CPTC and FTC groups, but the clinical stage of FTC was more advanced than that of RAS-like FVPTC group (P<0.01) or CPTC group (P<0.01). The real-time fluorescence quantitative PCR showed that the RAS mutation rate in FTC was the highest (61.5%), significantly higher than that in others (P<0.01). The RAS mutation rate in CPTC was the lowest (4.8%), while those in RAS-like FVPTC, FTA and adenomatous hyperplasia were similar (about 15%). The Spearman rank correlation analysis showed that the RAS mutation was not correlated with age, sex or tumor size in benign lesions (FTA and adenomatous hyperplasia), nor was it associated with age, sex, tumor size, lymph node metastasis, spreading of tumors to thyroid and clinical stage in malignant tumors (RAS-like FVPTC, CPTC and FTC). Conclusions: RAS mutation can occur in both benign and malignant thyroid tumors with follicular differentiation, in which the incidence is the highest in FTC. Both morphologic and immunohistochemical changes should be taken into account. The molecular genetics of RAS-like FVPTC is similar to FTA and adenomatous hyperplasia. RAS gene mutation appears not to be a prognostic factor for thyroid diseases.


Assuntos
Carcinoma Papilar, Variante Folicular , Neoplasias da Glândula Tireoide , Feminino , Genes ras , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf
4.
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
5.
Magy Onkol ; 64(1): 76-78, 2020 Mar 17.
Artigo em Húngaro | MEDLINE | ID: mdl-32181767

RESUMO

Targeted therapy for V600 BRAF mutant solid tumors already exists but resistance to the treatment is still a serious problem to be solved. Moreover, there are currently no approved targeted therapeutic options against non-V600 BRAF mutant tumors. Here we studied targeted therapy resistance mechanisms of V600 BRAF mutant melanoma and also explored potential alternative solutions for their treatment. In V600 BRAF mutant melanoma cells that did not or slightly express PTEN protein, prenylation inhibitor zoledronic acid inhibited cell proliferation and induced apoptosis more profoundly than in melanoma cells expressing PTEN. We also investigated the proliferation and migration of pre- and posttreatment isogeneic melanoma cell line pairs. Posttreatment V600 BRAF mutant melanoma cells showed more invasive phenotype. We found that migration and proliferation showed a negative correlation with MITF and FRA-1 mRNA levels, respectively. Both transcription factors correlated with EGFR mRNA expression. Finally, in non-V600 BRAF mutant cell lines combined inhibition of pan-RAF and MEK with sorafenib/AZ628 and selumetinib showed significantly stronger cell growth, cell migration and Erk activation inhibition and also increased apoptosis induction compared to single treatments.


Assuntos
Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Humanos , Melanoma/enzimologia , Melanoma/genética , Melanoma/patologia , Mutação , Proteínas Proto-Oncogênicas B-raf/genética
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 354-358, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027303

RESUMO

Abstract  Langerhans cell histiocytosis (LCH) is a disease originated from bone marrow dendritic cells, and classified as a tumor by the discovery of a recurrent somatic BRAF-V600E point mutation in the RAS-RAF-MEK-ERK signaling pathway. The clinical manifestations of LCH are mainly granulomatous lesions composed of clonal pathological tissue cells. According to the lesions and invasive risk organs, it is divided into single system diseases, multi-system diseases with risk-free organ infiltration and multi-system diseases with risk organ infiltration. The diagnosis was based on immunohistochemical pathological dendritic cell-specific markers CD1α++and/or CD207+,therefore, according to risk stratification, the regiment and intensity of combination chemotherapy and targeted therapy are drawn up. Prognosis is associates with risk organ infiltration, initial treatment response, and BRAF mutations. Due to the low incidence and lack of systematic knowledge, the clinical understanding of this disease is insufficient, thus the rates of misdiagnosis and therapeutic error are high. In this review, the pathogenesis, clinical manifestations, diagnostic and treatment are summarized. So on to provide a theroretical basis for clinical diagnosis and treatment of the diseases.


Assuntos
Histiocitose de Células de Langerhans , Células Dendríticas , Humanos , Sistema de Sinalização das MAP Quinases , Mutação , Proteínas Proto-Oncogênicas B-raf , Transdução de Sinais
12.
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
14.
PLoS One ; 15(2): e0228188, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32045431

RESUMO

OBJECTIVES: Oncology has become more reliant on new testing methods and a greater use of electronic medical records, which provide a plethora of information available to physicians and researchers. However, to take advantage of vital clinical and research data for precision medicine, we must initially make an effort to create an infrastructure for the collection, storage, and utilization of this information with uniquely designed disease-specific registries that could support the collection of a large number of patients. MATERIALS AND METHODS: In this study, we perform an in-depth analysis of a series of lung adenocarcinoma patients (n = 415) with genomic and clinical data in a recently created thoracic patient registry. RESULTS: Of the 415 patients with lung adenocarcinoma, 59% (n = 245) were female; the median age was 64 (range, 22-92) years with a median OS of 33.29 months (95% CI, 29.77-39.48). The most common actionable alterations were identified in EGFR (n = 177/415 [42.7%]), ALK (n = 28/377 [7.4%]), and BRAF V600E (n = 7/288 [2.4%]). There was also a discernible difference in survival for 222 patients, who had an actionable alteration, with a median OS of 39.8 months as compared to 193 wild-type patients with a median OS of 26.0 months (P<0.001). We identified an unprecedented number of actionable alterations [53.5% (222/415)], including distinct individual alteration rates, as compared with 15.0% and 22.3% in TCGA and GENIE respectively. CONCLUSION: The use of patient registries, focused genomic panels and the appropriate use of clinical guidelines in community and academic settings may influence cohort selection for clinical trials and improve survival outcomes.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Medicina de Precisão , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico/genética , Receptores ErbB/genética , Feminino , Variação Genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas B-raf/genética , Sistema de Registros , Estudos Retrospectivos , Adulto Jovem
15.
Medicine (Baltimore) ; 99(3): e18880, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011515

RESUMO

INTRODUCTION: Pleomorphic xanthoastrocytomas (PXA) are rare, typically benign, slow-growing tumors that commonly occur in the cerebral hemispheres. We describe two cases of clinically aggressive PXA with uncommon locations; one was in the tectal plate, and the other had simultaneous multicentric lesions. PATIENT CONCERNS: The both cases presented with severe headache with no significant past medical history. DIAGNOSIS: PXA World Health Organization grade II were histopathologically diagnosed from surgically resected specimens, and immunohistochemical and sequence analysis revealed a high Ki-67 proliferative index and BRAF V600E mutation in both the cases. INTERVENTIONS: The first case presented with multicentric lesions and underwent partial resection, whereas the second case presented with a tectal plate tumor that was managed by gross total surgical resection. Strong 5-aminolevulinic acid (5-ALA)-induced fluorescence was observed in both the lesions. Postoperative radiotherapy plus concomitant and adjuvant temozolomide was administered to both the patients. OUTCOMES: Despite completing adjuvant chemo-radiotherapy, both the patients had local tumor recurrence at 2 and 5 months after the operation, respectively. CONCLUSION: The progressive clinical courses in our cases suggest that additional postoperative therapy should be considered during the treatment of PXA with a high Ki67 index, and that temozolomide with radiotherapy, followed by temozolomide maintenance therapy, may not prevent recurrence in such tumors. Importantly, our experience implies that unlike other subtypes of low grade gliomas, 5-ALA fluorescence is useful for intraoperative visualization of PXA.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Astrocitoma/diagnóstico por imagem , Astrocitoma/genética , Astrocitoma/terapia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Terapia Combinada , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Antígeno Ki-67/genética , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Neoplasia Residual/diagnóstico por imagem , Neoplasia Residual/genética , Neoplasia Residual/terapia , Proteínas Proto-Oncogênicas B-raf/genética , Adulto Jovem
16.
Medicine (Baltimore) ; 99(5): e18917, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32000400

RESUMO

BACKGROUND: B-type Raf kinase (BRAF) mutation is proved to be a critical predictive factor in papillary thyroid cancer (PTC) with aggressive characteristics. However, the association between BRAF mutation and cervical lymphatic metastasis in PTC is controversial. METHODS: We searched papers on the study of BRAF mutation and cervical lymphatic metastasis in PTC patients through PubMed, Web of Science, Embase, and Cochranelibrary. The BRAF (+) cases, BRAF (-) cases, and cervical lymphphatic metastatic cases in both BRAF (+) and BRAF (-) groups were collected. After Quality assessment, statistical Analysis (funnel plot and Harbord evaluation, Random-effect model, heterogeneity, subgroup analysis, sensitivity analysis, and metacum analysis) were done by the Review Manager (RevMan) 5.3 and stata14 statistical software. RESULTS: There were 78 cross-section studies which met our inclusion criteria. And all of them had no selection bias, publication bias, or any other bias. A significant association existed between BRAF mutation and cervical lymph node metastasis (LNM) (odds ratio [OR] = 1.63; 95% confidence interval [CI]: 1.44-1.84; P < .05). Overall, 46 studies were conducted among East Asians. Twenty four articles had provided the data of central lymph node metastasis (CLNM), 11 articles with the data of lateral lymph node metastasis (LLNM), and classic/conventional PTC (CPTC) was analyzed in 10 studies. Subgroup analyses were performed based on ethnicity, metastatic site, and subtype of PTC. Significant association between BRAF (+) mutation and cervical LNM were indicated in East Asians (OR = 1.73; 95% CI: 1.49-2.02; P < .05), in non-East Asians (OR = 1.57; 95% CI: 1.26-1.96; P < .05), and in CLNM (OR = 1.80; 95% CI: 1.56-2.07; P < .05). While no significant association was found in LLNM (OR = 1.37; 95% CI: 0.76-2.48; P = .29 > .05) and in CPTC (OR = 1.32; 95% CI: 0.97-1.80; P = .08 > .05). We did not find any other major changes when sensitivity analysis was performed. The metacum analysis showed no significant association existed before 2012. While a significant association began to exist between BRAF mutation and LNM from 2012, and this association became stable from 2017. CONCLUSIONS: We consider that a significant association exists between BRAF mutation and cervical LNM. Further meta-analysis on subgroup may reveal some valuable factors between BRAF gene mutation and LNM. And we do not recommend that BRAF (+) as the biomarker for LNM in PTC.


Assuntos
Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Quinases raf/genética , Humanos , Metástase Linfática , Pescoço/patologia , Câncer Papilífero da Tireoide/patologia
17.
Crit Rev Oncol Hematol ; 146: 102859, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31927392

RESUMO

Lung and colorectal cancer are included in the most tremendously threatening diseases in terms of incidence and death. Although they are located in completely different organs and differ in various characteristics they do share some common features, especially regarding their molecular mutational profile. Among several commonly mutated genes KRAS and BRAF are spotted to be highly associated with patient's poor disease outcome and resistance to targeted therapies mostly in liaison with other mutant activated genes. Many studies have shed light in these mechanisms for disease progression and numerous preclinical models, clinical trials and meta-analysis reports investigate the impact of specific treatments or combination of therapies. The present review is an effort to compare the mutational imprint of these genes between the two diseases and their impact in prognosis, current therapy, mechanisms of therapy resistance and future therapeutic plans and provide a spherical perspective regarding the systemic molecular profile of cancer.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas ras/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Colorretais/patologia , Progressão da Doença , Humanos , Neoplasias Pulmonares/patologia , Mutação/genética , Valor Preditivo dos Testes , Prognóstico , Resultado do Tratamento
18.
Am J Clin Nutr ; 111(3): 562-569, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31897467

RESUMO

BACKGROUND: Observational studies have consistently shown that a high BMI is associated with increased risk of colorectal cancer (CRC). However, the underlying mechanisms linking obesity to CRC remain unclear. OBJECTIVES: To investigate the associations of BMI and CRC by major molecular pathological subtypes of CRC. METHODS: This analysis included 2407 cases and 2454 controls from a large German population-based case-control study. Information on recent weight and height as well as other demographic and lifestyle data were obtained by standardized interviews. Multinomial logistic regression was used to estimate ORs and 95% CIs for the associations between BMI and risk of CRC by major molecular pathological features: microsatellite instability (MSI), CpG island methylator phenotype (CIMP), B-Raf proto-oncogene serine/threonine kinase (BRAF) mutation, and Kirsten rat sarcoma viral oncogene homolog gene (KRAS) mutation. RESULTS: Among women, a higher BMI was differentially and more strongly associated with risk of MSI CRC (OR per 5 kg/m2: 1.69; 95% CI: 1.34, 2.12; Pheterogeneity ≤ 0.001), CIMP-high CRC (OR per 5 kg/m2: 1.57; 95% CI: 1.30, 1.89; Pheterogeneity ≤ 0.001), BRAF-mutated CRC (OR per 5 kg/m2: 1.56; 95% CI: 1.22, 1.99; Pheterogeneity = 0.04), and KRAS-wildtype CRC (OR per 5 kg/m2: 1.35; 95% CI: 1.17, 1.54; Pheterogeneity = 0.01), compared with the risk of CRC in subjects with the molecular feature counterpart. In men, no meaningful differences in CRC risk were observed for the investigated molecular feature pairs. For the association of BMI with MSI CRC, we observed effect modification by sex (Pinteraction = 0.04). Also, in women, the risk of CRC with the serrated pathway features was more strongly increased with higher BMI than risk of CRC with the traditional pathway features (OR per 5 kg/m2: 1.73; 95% CI: 1.28, 2.34; Pheterogeneity = 0.01). CONCLUSIONS: In women, the relation between BMI and MSI-high CRC seems to be stronger than that between BMI and microsatellite-stable CRC. However, a validation in an independent cohort is needed. This observational study was registered at the German Clinical Trials Register (http://www.drks.de; study ID: DRKS00011793), an approved primary register in the WHO network.


Assuntos
Índice de Massa Corporal , Neoplasias Colorretais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Neoplasias Colorretais/fisiopatologia , Ilhas de CpG , Metilação de DNA , Feminino , Alemanha , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto Jovem
19.
PLoS One ; 15(1): e0227294, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31940389

RESUMO

BACKGROUND: Cell-free DNA detection is becoming a surrogate assay for tumor genotyping. Biological fluids often content a very low amount of cell-free tumor DNA and assays able to detect very low allele frequency mutant with a few quantities of DNA are required. We evaluated the ability of the fully-automated molecular diagnostics platform Idylla for the detection of KRAS, NRAS and BRAF hotspot mutations in plasma from patients with metastatic colorectal cancer (mCRC). MATERIALS AND METHODS: First, we evaluated the limit of detection of the system using two set of laboratory made samples that mimic mCRC patient plasma, then plasma samples from patients with mCRC were assessed using Idylla system and BEAMing digital PCR technology. RESULTS: Limits of detection of 0.1%, 0.4% and 0.01% for KRAS, NRAS and BRAF respectively have been reached. With our laboratory made samples, sensitivity up to 0.008% has been reached. Among 15 patients' samples tested for KRAS mutation, 2 discrepant results were found between Idylla and BEAMing dPCR. A 100% concordance between the two assays has been found for the detection of NRAS and BRAF mutations in plasma samples. CONCLUSIONS: The Idylla system does not reach as high sensitivity as assays like ddPCR but has an equivalent sensitivity to modified NGS technics with a lower cost and a lower time to results. These data allowed to consider the Idylla system in a routine laboratory workflow for KRAS, NRAS and BRAF mutations detection in plasma.


Assuntos
Biomarcadores Tumorais/genética , DNA Tumoral Circulante/isolamento & purificação , Neoplasias Colorretais/diagnóstico , Análise Mutacional de DNA/instrumentação , Técnicas de Genotipagem/instrumentação , Linhagem Celular Tumoral , DNA Tumoral Circulante/genética , Ensaios Clínicos como Assunto , Neoplasias Colorretais/genética , Análise Mutacional de DNA/métodos , GTP Fosfo-Hidrolases/genética , Frequência do Gene , Técnicas de Genotipagem/métodos , Humanos , Limite de Detecção , Proteínas de Membrana/genética , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Sensibilidade e Especificidade
20.
Am J Pathol ; 190(3): 702-710, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31953036

RESUMO

Papillary thyroid carcinomas (PTCs) account for 90% of human thyroid cancer cases, which represent 1% of all cancer cases. They are likely to develop from papillary thyroid microcarcinomas (PTMCs), found in up to 36% of healthy individuals, due to rare progression events (0.01%). Although the prognosis of PTCs is excellent, 5% to 10% of tumors display an unfavorable outcome. About 45% of PTCs exhibit activating BRAFV600E mutations. Rats of the inbred BD strains postnatally exposed to the carcinogen N-ethyl-N-nitrosourea developed PTMCs, which closely resembled their human counterparts judging from their histology, size, and marginal tendency to progress. DNA sequencing revealed mutations in exon 15 of the Braf gene identical to the human BRAFV600E mutation in 82% of the cases. Predominantly a 50:50 ratio of wild-type to mutant Braf alleles was seen regardless of tumor size or animal age, indicating that the Braf mutation is an early, if not the initial, event in rat PTMC development. Surprisingly, most PTMCs carrying a confirmed BrafV600E mutation did not display BrafV600E protein expression. As the BrafV600Egene is supposed to be the driver in PTC development, down-regulation of expression should contribute to the low risk for progression of PTMC. This model system will enable further insights into the molecular mechanisms of PTMC initiation and progression to PTC, further translating into targeted tumor prevention strategies/therapies.


Assuntos
Carcinoma Papilar/patologia , Etilnitrosoureia/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Alelos , Substituição de Aminoácidos , Animais , Modelos Animais de Doenças , Éxons/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Mutação , Prognóstico , Ratos , Análise de Sequência de DNA , Câncer Papilífero da Tireoide/induzido quimicamente , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/induzido quimicamente , Neoplasias da Glândula Tireoide/patologia
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