• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5
  • 4
  • 1
  • 1
  • Tagged with
  • 13
  • 7
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Análise da mutação BRAFV600E em carcinoma papilífero de tireoide

Pereira, Danielle Pessôa January 2014 (has links)
Submitted by ROBERTO PAULO CORREIA DE ARAÚJO (ppgorgsistem@ufba.br) on 2015-07-17T19:51:36Z No. of bitstreams: 1 PEREIRA, Danielle Pessôa.pdf: 2273847 bytes, checksum: 9fd911d989bc9942943233a4ba36bf38 (MD5) / Made available in DSpace on 2015-07-17T19:51:36Z (GMT). No. of bitstreams: 1 PEREIRA, Danielle Pessôa.pdf: 2273847 bytes, checksum: 9fd911d989bc9942943233a4ba36bf38 (MD5) / Este trabalho foi financiado pela Fundação de Amparo à Pesquisa no Estado da Bahia (FAPESB) / Introdução: A oncogênese tireoidiana frequentemente envolve a ativação constitutiva da via RAS-RAF-MEK-ERK. A mutação BRAFV600E contribui para a sua ativação e tem sido considerada o evento oncogênico mais frequente do carcinoma papilífero de tireoide (CPT). Estudos clínicos e experimentais têm predominantemente demonstrado associação positiva entre a presença da mutação BRAFV600E e mau prognóstico do CPT. No entanto, alguns estudos não constataram esta associação, indicando que ainda há discrepâncias e variabilidade nos resultados obtidos. Objetivos: Determinar a prevalência da mutação BRAFV600E em casos consecutivos de CPT em pacientes diagnosticados e tratados no Hospital São Rafael, SalvadorBahia-Brasil e associar a presença da mutação com aspectos clinicopatológicos conhecidos do CPT e risco de recorrência segundo protocolos do Consenso Brasileiro e a American Thyroid Association. Metodologia: Estudo retrospectivo de 135 casos consecutivos de CPT. Extração de DNA de tecido tumoral parafinado. Reação em cadeia da polimerase e sequenciamento direto do exon 15 do gene BRAF. Dados clínicos e patológicos foram obtidos através da revisão de prontuários físicos e eletrônicos. A positividade da mutação BRAFV600E foi confrontada com os aspectos clinicopatológicos dos pacientes utilizando Teste de Qui-Quadrado e análise multivariada de regressão logística. Resultados: A prevalência da mutação BRAFV600E foi de 65,1% (28/43). A mutação BRAFV600E esteve positivamente associada com idade avançada (40,96 ± 13,69 vs 29,73 ± 10,18; P = 0,008) e negativamente com presença de tireoidite de Hashimoto (TH) (25% vs 66,7%; P = 0,008). Contudo, o efeito independente foi somente observado para TH (OR: 0,14; P = 0,024). Neste estudo, não foram observadas associações com o sexo do paciente, história familiar, subtipo histológico, tamanho tumoral, multifocalidade, invasão vascular, metástases linfonodais e à distância, estádio clínico avançado (TNM/AJCC) e risco de recorrência tumoral. Conclusão: A prevalência da mutação BRAFV600E foi semelhante à apresentada em estudos prévios. A mutação BRAFV600E não esteve associada com a maioria dos aspectos clinicopatológicos investigados. Tireoidite de Hashimoto esteve negativamente associado com a mutação BRAFV600E . / Background: Thyroid oncogenesis often involves constitutive activation of the RAS-RAFMEK-ERK pathway. BRAFV600E mutation contributes to this activation and has been considered the most frequent oncogenic event in papillary thyroid carcinoma (PTC). Clinical and experimental studies have predominantly demonstrated positive association between presence of BRAFV600E mutation and poor PTC prognosis. However, some studies have not found this association, so there still are discrepancies and variability in the results obtained. Objectives: To determine the BRAFV600E mutation prevalence in consecutive cases of PTC in patients diagnosed and treated at São Rafael’s Hospital, Salvador-Bahia-Brazil, and associate its presence with known clinicopathological aspects of PTC and recurrence risk according to Brazilian's Consensus and American Thyroid Association guidelines. Methods: Retrospective study of 135 consecutive cases of PTC. DNA extraction from paraffin-embedded tumor tissue. Polymerase chain reaction and direct sequencing of exon 15 of BRAF gene. Clinical and pathological data were obtained through review of physical and electronic records. BRAFV600E mutation positivity was confronted with the clinicopathological features of patients using chisquare test and multivariate logistic regression analysis. Results: BRAFV600E mutation prevalence was 65.1% (28/43). BRAFV600E mutation was positively associated with older age (40.96 ± 13.69 vs 29.73 ± 10.18, P = 0.008) and negatively with the presence of Hashimoto's thyroiditis (HT) (25% vs 66.7%; P = 0.008). However, the independent effect was only observed for HT (OR: 0.14, P = 0.024). In this study, associations with patient gender, familial history, histologic subtype, tumor size, multifocality, vascular invasion, lymph node and distant metastases, advanced clinical stage (TNM/AJCC) and risk of tumor recurrence were not observed. Conclusion: BRAFV600E mutation prevalence was similar to the presented in previous studies. BRAFV600E mutation was not associated with most clinicopathological aspects investigated. Hashimoto's thyroiditis was negatively associated with BRAFV600E mutation.
2

Efeitos citotóxicos do DM-1 em células de melanoma resistentes a um inibidor de BRAF e na expressão de metaloproteinases / DM-1 cytotoxic effects in BRAF resistant melanoma cell lines and metalloproteinase expression modulation.

Souza, Nayane de 25 October 2017 (has links)
Melanoma é o câncer mais agressivo e a mutação BRAF V600E é a mais frequente entre os pacientes. O vemurafenibe foi o primeiro inibidor específico desta mutação aprovado pela Food and Drug Administration. Entretanto, após cerca de seis meses há recidiva e superar os mecanismos de resistência responsáveis por este fenômeno ainda é um desafio. A curcumina é um tumérico com características antitumorais e anti-inflamatórias, entretanto sua baixa biodisponibilidade e estabilidade limitam seu uso e por isso impulsionaram a busca por análogos capazes de serem eficientes e comercializados. O DM-1, é um análogo monocetônico que apresentou efeitos antiumorais in vitro e in vivo em estudos anteriores. O objetivo deste trabalho foi avaliar os efeitos citotóxicos do DM-1 em células de melanoma sensíveis (naive) e resistentes ao vemurafenibe, bem como na modulação de metaloproteinases. As células de melanoma foram tratadas com diferentes concentrações de DM-1, e este composto foi citotóxico para linhagens sensíveis e resistentes ao vemurafenibe, além de induzir parada de ciclo celular em G1/G0 e diminuir o número de colônias, entretanto ele não foi seletivo em ensaios de citotoxicidade realizados com melanócitos e fibroblastos. O tratamento dessas células em doses subtóxicas resultou na modulação de metaloproteinases importantes no processo de invasão celular. O DM-1 reduziu as concentrações das metaloproteinases -1, -2 e -9 (MMP-1, -2 e -9) em um ensaio de quantificação de MMPs e a atividade das MMP-2 e -9 em um ensaio de zimografia de maneira célula dependente. As modulações negativas do inibidor de MMP TIMP-2 e MMP-14 para SKMEL-28 naive foram associadas a diminuição das atividades de MMP-2 e -9, enquanto que as modulações positivas para SKMEL-19 naive foram relacionadas ao aumento de MMP-2. Este composto ainda inibiu a migração das células e a formação de tubos por células endoteliais. / Malignant melanoma is the most aggressive cancer and the BRAF V600E mutation is the most frequent among patients. Vemurafenib was the first specific inhibitor for this mutation approved by Food and Drug Administration. Therefore around six months later there is relapse and overcoming it is still a challenge. Curcumin is a turmeric and it has been deeply researched because of its anti-inflammatory and antitumoral effects. However the low stability limits its use, therefore, encouraged the investigation of analogues capable to be efficient and commercialized. DM-1 is a monoketone curcumin analog and it showed antitumoral effects in vitro and in vivo in previous studies The aim of this project was to evaluate the cytotoxical effects of DM-1 for vemurafenib responsive (naïve) and resistant melanoma cells, as well as metalloproteinases modulation. Melanoma cells were treated with different DM-1 concentrations, and this compound was cytotoxic for responsive and resistant cell lines, besides inducing G1/G0 cell cycle arrest and reducing the number of colonies, nonetheless it was not selective in assays performed with melanocytes and fibroblasts. Subtoxic treatment of those cells modulated important MMPs in the cell invasion process. DM-1 reduced metalloproteinases -1, -2 and -9 (MMP-1,-2 and -9) in a quantification assay, and MMP-2 and -9 activities by zymography in a cell-dependent way. Negative modulations of MMP inhibitor TIMP-2 and MMP-14 for SKMEL-28 naïve were associated with MMP-2 and -9 reduced activities, whereas positive modulations for SKMEL-19 naïve were correlated to MMP-2 increase. Furthermore, this compound reduced migration of those cells and endothelial cell tube formation.
3

Efeitos citotóxicos do DM-1 em células de melanoma resistentes a um inibidor de BRAF e na expressão de metaloproteinases / DM-1 cytotoxic effects in BRAF resistant melanoma cell lines and metalloproteinase expression modulation.

Nayane de Souza 25 October 2017 (has links)
Melanoma é o câncer mais agressivo e a mutação BRAF V600E é a mais frequente entre os pacientes. O vemurafenibe foi o primeiro inibidor específico desta mutação aprovado pela Food and Drug Administration. Entretanto, após cerca de seis meses há recidiva e superar os mecanismos de resistência responsáveis por este fenômeno ainda é um desafio. A curcumina é um tumérico com características antitumorais e anti-inflamatórias, entretanto sua baixa biodisponibilidade e estabilidade limitam seu uso e por isso impulsionaram a busca por análogos capazes de serem eficientes e comercializados. O DM-1, é um análogo monocetônico que apresentou efeitos antiumorais in vitro e in vivo em estudos anteriores. O objetivo deste trabalho foi avaliar os efeitos citotóxicos do DM-1 em células de melanoma sensíveis (naive) e resistentes ao vemurafenibe, bem como na modulação de metaloproteinases. As células de melanoma foram tratadas com diferentes concentrações de DM-1, e este composto foi citotóxico para linhagens sensíveis e resistentes ao vemurafenibe, além de induzir parada de ciclo celular em G1/G0 e diminuir o número de colônias, entretanto ele não foi seletivo em ensaios de citotoxicidade realizados com melanócitos e fibroblastos. O tratamento dessas células em doses subtóxicas resultou na modulação de metaloproteinases importantes no processo de invasão celular. O DM-1 reduziu as concentrações das metaloproteinases -1, -2 e -9 (MMP-1, -2 e -9) em um ensaio de quantificação de MMPs e a atividade das MMP-2 e -9 em um ensaio de zimografia de maneira célula dependente. As modulações negativas do inibidor de MMP TIMP-2 e MMP-14 para SKMEL-28 naive foram associadas a diminuição das atividades de MMP-2 e -9, enquanto que as modulações positivas para SKMEL-19 naive foram relacionadas ao aumento de MMP-2. Este composto ainda inibiu a migração das células e a formação de tubos por células endoteliais. / Malignant melanoma is the most aggressive cancer and the BRAF V600E mutation is the most frequent among patients. Vemurafenib was the first specific inhibitor for this mutation approved by Food and Drug Administration. Therefore around six months later there is relapse and overcoming it is still a challenge. Curcumin is a turmeric and it has been deeply researched because of its anti-inflammatory and antitumoral effects. However the low stability limits its use, therefore, encouraged the investigation of analogues capable to be efficient and commercialized. DM-1 is a monoketone curcumin analog and it showed antitumoral effects in vitro and in vivo in previous studies The aim of this project was to evaluate the cytotoxical effects of DM-1 for vemurafenib responsive (naïve) and resistant melanoma cells, as well as metalloproteinases modulation. Melanoma cells were treated with different DM-1 concentrations, and this compound was cytotoxic for responsive and resistant cell lines, besides inducing G1/G0 cell cycle arrest and reducing the number of colonies, nonetheless it was not selective in assays performed with melanocytes and fibroblasts. Subtoxic treatment of those cells modulated important MMPs in the cell invasion process. DM-1 reduced metalloproteinases -1, -2 and -9 (MMP-1,-2 and -9) in a quantification assay, and MMP-2 and -9 activities by zymography in a cell-dependent way. Negative modulations of MMP inhibitor TIMP-2 and MMP-14 for SKMEL-28 naïve were associated with MMP-2 and -9 reduced activities, whereas positive modulations for SKMEL-19 naïve were correlated to MMP-2 increase. Furthermore, this compound reduced migration of those cells and endothelial cell tube formation.
4

Identification of KIT as a Suppressor of BRAFV600E-Mutant Melanoma

Neiswender, James V. 09 November 2017 (has links)
Genetic changes acquired in the pigment producing cells of the skin, called melanocytes, can lead to formation of the deadly cancer melanoma. Mutations or amplifications leading to the activation of the RAS/MAPK pathway occur in more than 90% of melanomas. Melanocyte development and survival requires the stimulation of this pathway by the receptor tyrosine kinase (RTK) KIT. In ~2% of melanomas, oncogenic KIT mutations drive tumor formation; however, the majority of melanomas lose wild-type KIT expression, suggesting that KIT could suppress melanoma formation. In human melanoma patients of The Cancer Genome Atlas (TCGA), we found an association between BRAFV600E mutations and low KIT mRNA expression, so we tested whether KIT loss would affect BRAFV600E-driven tumor onset by crossing a kit(lf) mutant allele into melanoma-prone Tg(mitfa:BRAFV600E); p53(lf) zebrafish. We observed that kit(lf)-mutant zebrafish experienced accelerated tumor onset and their tumors had increased RAS/MAPK pathway activation. In BRAFV600E-mutant melanoma cells, KIT activity reduced RAS/MAPK signaling by promoting activation of wild-type BRAF (BRAFWT). Furthermore, we found that overexpression of BRAFWT delayed tumor onset in Tg(mitfa:BRAFV600E); p53(lf); mitfa(lf) zebrafish, but had no effect in kit(lf); Tg(mitfa:BRAFV600E); p53(lf); mtifa(lf) zebrafish and a cohort of TCGA BRAFV600E-mutant melanoma patients with high KIT expression and high BRAFWT allele ratios experienced a reduced likelihood of metastasis and extended overall survival. These studies indicate that wild-type KIT acts to suppress melanoma formation through activation of BRAFWT, causing reduced signaling output of BRAFV600E-mutant cells.
5

Estudo da associaÃÃo entre a acromegalia e a presenÃa da mutaÃÃo BRAFV600E e a expressÃo imunohistoquÃmica de IGF-1 e galectina-3 no carcinoma papilÃfero de tireoide. / Study of the association between acromegaly and the presence of BRAFV600E mutation and immunohistochemical expression of IGF-1 and galectin-3 in papillary thyroid carcinoma.

Renan MagalhÃes Montenegro 31 August 2012 (has links)
nÃo hà / INTRODUÃÃO: Estudos epidemiolÃgicos sugerem que o carcinoma de tireoide seja a neoplasia maligna mais frequente nos pacientes acromegÃlicos. Atà este momento nÃo hà relatos de estudos avaliando marcadores moleculares do carcinoma papilÃfero de tireoide (CPT) nessa populaÃÃo. OBJETIVOS: Avaliar a associaÃÃo entre acromegalia, presenÃa da mutaÃÃo BRAFV600E, marcadores imunohistoquÃmicos (galectina-3 e IGF-1) e caracterÃsticas clÃnico-patolÃgicas em pacientes acromegÃlicos com CPT. MATERIAL E MÃTODOS: Trata-se de um estudo transversal realizado no perÃodo de janeiro/09 a dezembro/2011, onde 11 pacientes acromegÃlicos com CPT, provenientes de 5 centros brasileiros de referÃncia no tratamento da acromegalia foram comparados com 45 pacientes com CPT sem acromegalia. Foram estudadas variÃveis clÃnicas e histopatolÃgicas do CPT. Utilizou-se cortes histolÃgicos de CPT emblocados em parafina para o estudo da mutaÃÃo BRAFV600E e para a anÃlise imunohistoquÃmica dos marcadores IGF-1 e galectina-3. Na anÃlise utilizou-se os testes t de student e do qui-quadrado (software SPSS, versÃo 13.0 para Windows) (p<0,05). RESULTADOS: A idade mÃdia dos pacientes acromegÃlicos com CPT foi de 61,5  6,02 anos, sendo 72,7% do sexo feminino. O tempo mÃdio de diagnÃstico da acromegalia foi de 7,7  3,90 anos, sendo o intervalo entre o diagnÃstico da acromegalia e do CPT, em mÃdia, 3,4  2,71 anos. Os nÃveis sÃricos de IGF-1 dos acromegÃlicos ao diagnÃstico do CPT foi de 417,0 ng/mL. NÃo houve diferenÃa quanto ao estadiamento TNM (Tumor, Nodule, Metastasis) e Ãndice prognÃstico AMES (Ages, Metastasis, Extent, Size) entre os grupos. Houve maior prevalÃncia da mutaÃÃo BRAFV600E (90,9% vs 55,6%; p=0,039) e de forte imunoexpressÃo para IGF-1 (88,9% vs 38,1%; p= 0,017) nos acromegÃlicos. NÃo houve diferenÃa na expressÃo de galectina-3 entre os grupos. CONCLUSÃO: Neste trabalho, pela primeira vez se mostrou uma alta prevalÃncia da mutaÃÃo BRAFV600E em CPT de acromegÃlicos, muito superior à descrita na populaÃÃo com CPT neste e em estudos anteriores (cerca de 40%). Contudo essa mutaÃÃo nÃo se mostrou associada a um fenÃtipo mais agressivo do tumor, o que diverge dos achados em populaÃÃo nÃo acromegÃlica com CPT. Conclui-se que a acromegalia à possivelmente associada à mutaÃÃo BRAFV600E em pacientes acromegÃlicos com CPT. Novos estudos serÃo necessÃrios para definir os mecanismos responsÃveis por tal associaÃÃo. / INTRODUCTION: Epidemiological studies suggest that thyroid carcinoma is the most common malignant neoplasm in acromegalic patients. At this moment there are no reports of studies evaluating molecular markers of papillary thyroid carcinoma (PTC) in this population. OBJECTIVES: The present work aimed to evaluate the association between acromegaly, expression of the mutation BRAFV600E, immunohistochemical markers (galectin-3 and IGF-1), and clinical-pathological characteristics in acromegalic patients with PTC. MATERIALS AND METHODS: This is a cross-sectional study conducted from January/09 to December/2011, where 11 acromegalic patients with CPT, from 5 Brazilian centers of reference in the treatment of acromegaly were compared with 45 patients with acromegaly without PTC. We evaluated clinical and histopathological variables of PTC. We used histological PTC embedded in paraffin for mutation study BRAFV600E and immunohistochemical analysis of markers IGF-1 and galectin-3. In the analysis we used the Student t test and chi-square test (SPSS software, version 13.0 for Windows) (p <0.05). RESULTS: The average age of acromegalic patients with PTC was 61.5  6.02 years and 72.7% were female. The average time of diagnosis of acromegaly was 7.7  3.90 years, and the interval between diagnosis of acromegaly and PTC was an average 3.4  2.71 years. The serum levels of IGF-1 in the diagnosis of acromegaly PTC was 417.0 ng / mL. There was no difference in the TNM (Tumor, Nodule, Metastasis) and AMES prognostic index (Ages, Metastasis, Extent, Size) between groups. There was a higher prevalence of the BRAFV600E mutation (90.9% vs 55.6%, p = 0.039) and stronger immunohistochemical expression for IGF-1 (88.9% vs 38.1%, p = 0.017) in acromegaly. There was no difference in the expression of galectin-3 between the groups. CONCLUSION: This work for the first time showed a high prevalence of mutations in BRAFV600E in PTC of acromegalic patients superior to those described in the population with PTC in this and previous studies (approximately 40%). However, this mutation was not associated with a more aggressive tumor phenotype, which differs from the findings in acromegalic population without PTC. We conclude that acromegaly is possibly associated to a mutation BRAFV600E in acromegalic patients with CPT. Further studies are needed to define the mechanisms responsible for this association.
6

Bases moléculaires de l’histiocytose langerhansienne / Molecular Basis of Langerhans Cell Histiocytosis

Héritier, Sébastien 04 January 2017 (has links)
L’histiocytose langerhansienne (HL) est la plus fréquente des histiocytoses, liée à l’accumulation de cellules pathologiques de phénotype langerhansien. La découverte de la mutation somatique BRAFV600E dans environ 50% des cas à ouvert un nouveau champ d’investigation pour tirer bénéfice de ce statut moléculaire pour la prise en charge des patients.Tout d’abord, nous avons montré l’efficacité des inhibiteurs de BRAF sans rapporter de résistance dans les formes actives d’HL, en particulier dans les formes multisystémiques avec atteinte des organes à risque (MS OR+) du nourrissons, confirmant le rôle driver de cette mutation dans l’HL. Toutefois, après l’arrêt du traitement administré durant 2 à 6 mois, de nombreuses récidives ont été constatées.Ensuite, nous avons montré que pour les enfants atteints d’HL, la mutation BRAFV600E était significativement associée aux formes MS OR+, retrouvée dans 87,8% de ces cas. Comparés aux patients non mutés BRAF, les patients avec la mutation BRAFV600E présentaient un taux de résistance plus élevé à la chimiothérapie de première ligne velbé - corticoïde (21,9% contre 3,3%), un taux plus élevé de réactivation à 5 ans (42,8% contre 28,1%) et un taux de séquelles supérieur (27,9% contre 12,6%).Par ailleurs, nous avons montré que, pour les HL BRAFV600E mutées, la quantification de BRAFV600E dans l’ADN libre circulant par PCR digitale en gouttelette était un biomarqueur pertinent pour les cas d’HL MS OR+ et les présentations résistantes au traitement de première ligne.Enfin, après un criblage de points chauds mutationnels d’une série d’échantillons tissulaires d’HL ayant permis de mettre en évidence un cas avec la mutation somatique PIK3CAE542K, 9 couples d’échantillons tumeur/constitutionnel ont été étudiés par séquençage d’exome. Cela nous a permis de mettre en évidence une mutation récurrente (n=2) de BRAF au niveau du site d’épissage 5’ (donneur) de l’intron 12. Selon l’analyse de l’ARN, cette mutation conduirait à l’insertion de 3 acides aminés (LLR) dans le domaine kinase de la protéine mutée, dont l’analyse fonctionnelle est en cours. / Langerhans cell histiocytosis (LCH) is the most common type of histiocytosis owing to accumulation of pathologic CD1a+ CD207+ histiocytes. The identification of BRAFV600E in more than half of patients with LCH has launched a new field of investigation to study potential patient’s management benefits and implications from this molecular status.First, in BRAFV600E mutated LCH, we reported the effectiveness of BRAF inhibitors. Efficacy with no resistance to vemurafenib was reported in all cases with active LCH disease, especially for multi-system LCH with risk organ (MS RO+) involvement, confirming the driver status of this mutation in LCH. However, after discontinuation of this treatment administered during 2-6 months, many recurrences were observed.Then, we showed that children with BRAFV600E mutated LCH manifested more severe disease, comprised 87.8% of patients with MS RO+ involvement. Compared to patients with wild-type BRAF, patients with BRAFV600E more commonly displayed resistance to combined vinblastine and corticosteroid therapy (21.9% vs. 3.3%), showed a higher 5-year reactivation rate (42.8% vs. 28.1%) and had more long-term permanent consequences (27.9% vs. 12.6%).Moreover, we showed that BRAFV600E quantification in circulating cell-free DNA by droplet digital PCR is a relevant biomarker to monitor response to therapy for MS RO+ LCH and RO- LCH children who failed to respond to first line chemotherapy.Finally, after the screening of LCH biopsy (n=86) for the BRAF, KRAS, NRAS and PI3KCA most common mutations, leading to highlight one case with the PIK3CAE542K somatic mutation, 9 paired tumor-normal samples from children with LCH were analyzed by whole exome sequencing. Data showed a new BRAF recurrent mutation (n=2) in the 5′ splice sites of the intron 12. According to RNA analysis, this mutation would lead to the insertion of 3 amino acids (LLR) in the smaller N-terminal lobe of the BRAF kinase domain. Functional analysis is ongoing.
7

Análise da função vascular de tumores gerados com linhagem de melanoma humano BRAFV600E em camundongos expostos a atividade física voluntária / Analysis of vascular function of tumors generated with BRAFV600E human melanoma cell line in mice exposed to voluntary physical activity

Mororó, Janio da Silva 01 February 2019 (has links)
A vasculatura tumoral é estrutural e funcionalmente anormal em relação à vasculatura de órgãos normais, resultando em regiões de heterogeneidade intratumoral para concentração de oxigênio, nutrientes e células inflamatórias. Com isso a vascularização disfuncional muitas vezes leva à administração ineficiente de drogas, comprometendo portanto a eficácia do tratamento. Recentemente, foi demonstrado que terapias antiangiogênicas e exercícios físicos poderiam \"normalizar\" a vasculatura tumoral, melhorando a sobrevida em pacientes com câncer. No entanto seria importante analisar se em melanomas portadores da mutação BRAFV600E, que são altamente resistentes a terapia, se o exercício promoveria a normalização vascular. Este trabalho teve como objetivo analisar o impacto do exercício físico voluntário na função vascular de melanomas humanos com mutação BRAFV600E em camundongos imunodeficientes (BALB/c Nude). Em relação ao crescimento tumoral, não observamos diferenças significativas entre os grupos dos animais exercitados e sedentários, tampouco diferença nos níveis de expressão de genes característicos de macrófagos M1 e M2 no microambiente tumoral desses animais. Por outro lado, a análise de expressão de genes nas células tumorais demonstrou que 8 genes foram diferencialmente expressos no Grupo exercitado ( < 4 km) em relação ao Grupo Sedentário, dentre os quais: FLOT2, STK4, STAT3, LATS1, PTEN, MCL1, PCNA e ACTA2. Em adição, não observamos diferenças significativas no percentual de área necrótica, hipóxica e vasos CD31 positivos. Desse modo, concluímos que o exercício físico induz um aumento nos níveis de expressão de genes envolvidos em modificações epigenéticas, apoptose, proliferação e sobrevivência, ciclo celular e motilidade célula / The tumor vasculature is structurally and functionally abnormal in relation to the vasculature of normal organs, resulting in regions of intratumoral heterogeneity for oxygen parcial pressure, nutrients and inflammatory cells. Thus dysfunctional vascularization often leads to inefficient drug delivery, thereby compromising the efficacy of treatment. Recently, it has been demonstrated that anti-angiogenic therapies and physical exercises could \"normalize\" tumor vasculature, improving survival in patients with cancer. However, it would be important to analyze in BRAFV600E melanoma tumors, which are highly resistant to therapy, whether exercise would promote vascular normalization. Based on this, this work aimed to analyze the impact of voluntary physical exercise on the vascular function of human melanomas with BRAFV600E mutation in immunodeficient mice (BALB / c Nude). In relation to the tumor growth, we did not observe significant differences between the groups of the exercised and sedentary animals, neither difference in the expression levels of genes characteristic of M1 and M2 macrophages in the tumor microenvironment of these animals. On the other hand, analysis of gene expression in tumor cells showed that 8 genes were differentially expressed in the exercised group ( < 4 km) in comparision to the Sedentary Group, among them: FLOT2, STK4, STAT3, LATS1, PTEN, MCL1, PCNA and ACTA2. In addition, we did not observe any significant differences in the percentage of necrotic, hypoxic area and CD31 positive vessels. Thus, we concluded that physical exercise induces an increase in the expression levels of genes involved in epigenetic modifications, apoptosis, proliferation and survival, cell cycle and cell motility
8

LRIG1 korrelerar med sämre överlevnad och saknar terapeutisk potential i kolorektalcancer / LRIG1 Correlates with Worse Prognosis and Lacks Therapeutic Potential in Colorectal Cancer

Nordmark, Emelie January 2019 (has links)
No description available.
9

Development of quantitative methods for the determination of vemurafenib and its metabolites in human plasma

Strömqvist, Malin January 2014 (has links)
Vemurafenib is a potent serine/threonine kinase inhibitor and is registered as Zelboraf® for the treatment of metastatic melanomas harboring BRAFV600E mutations. There is a large individual variation in drug response and the side effects observed among patients treated with Zelboraf® has proven to be severe.  LC-MS/MS methods were developed to measure vemurafenib and its metabolites in human plasma for prediction of treatment outcome and side effects in order to individualize treatment with Zelboraf®.  A novel, rapid quantification method was developed for vemurafenib using a stable isotope labeled internal standard. The method was validated according to international guidelines with regard to calibration range, accuracy, precision, carry-over, dilution integrity, selectivity, matrix effects, recovery and stability. All parameters met the set acceptance criteria.  The first method suitable for quantifying vemurafenib metabolites in human plasma is presented. Lacking commercially available reference substances, human liver microsomes were used to produce the metabolites. In patient samples at steady-state five previously in vitro identified metabolites were quantified for the first time.
10

The Role of Bromodomain Containing Protein Nine (BRD9) in Melanogenesis and Melanoma

BASUROY, TUPA January 2018 (has links)
No description available.

Page generated in 0.0381 seconds