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  • 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.
141

Klinický význam biomarkerů pro posouzení agresivity a prognozu nemalobuněčného karcinomu plic / The clinical relevance of biomarkers for aggression assessment and prognosis in non-small cell lung cancer

Pražáková, Markéta January 2011 (has links)
Aim: The aim of this thesis was to measure a large spectrum of biomarkers in serum or plasma of patients with operable stage of NSCLC and to evaluate and compare the clinical utility of these biomarkers in the three most important clinical applications for NSCLC: diagnosis, prognosis and postsurgery follow up care. Patients and methods: Total of 22 biomarkers with the most promising profiles were monitored: 8 standard tumor markers (cytokeratines Cyfra 21-1, TPA, TPS, and MonoTotal, CEA, SCC, TK, Chromogranin A) and 14 potential useful biomarkers including pro-inflammatory cytokines IL-6, IL-8, MCP-1, pro-angiogenic cytokine VEGF, matrix metaloproteinases MMP-1, MMP-2, MMP-7, MMP-9 and their inhibitors TIMP-1 and TIMP-2, adhesion molecules ICAM-1, VCAM-1, growth factor IGF-1, and PAI-1 stimulating tumor growth and angiogenesis. With a view of evaluating the clinical relevance of these markers for NSCLC we measured serum or plasma levels of these 22 markers in group of 93 patients with NSCLC undergoing radical surgery and in group of 20 patients with benign lung disease. For biomarker measurement were used conventional immunoanalytic routine methods (IRMA, REA, CLIA, MEIA, TRACE, ELISA) and multiplex immunoanalytic method. Results: Cyfra 21-1, MonoTotal, TPA, TPS, CEA, SCC, Chromogranin A, TIMP-1, MMP-1,...
142

Risk factors for nonadherence to outpatient appointments in lung cancer patients and a review of the patient navigation system: a case-control study

Krieger, Rachel 22 January 2016 (has links)
BACKGROUND: There is a need to identify the populations at high risk of nonadherence to outpatient lung cancer appointments in order to reduce the delay from diagnosis to treatment. The patient navigation system, which helps patients with barriers navigate the health care system, was examined to see if the correct high-risk groups were being addressed. METHODS: A case-control study with 195 subjects from the lung cancer clinics at Boston Medical Center (BMC) was conducted examining three nonadherence case groups: no-shows (n=40), cancelations (n=64) and combined (n=20). Nonadherence was defined as any patient who was a no-show for at least one appointment or who canceled more than one appointment over the three month study period. The combined group incorporated both of these factors. The patients were stratified by 10 patient characteristics, including patient navigation. Odds ratios (ORs) and 95% confidence intervals (CIs) were used for the analysis. A second analysis was done on patients in the patient navigation program (n=33) to determine if the high risk groups identified were being addressed. This was done using ORs and 95% CIs. RESULTS: This study has shown that there are certain patient groups in the lung cancer clinics at BMC that are at higher risk of being nonadherent to lung cancer outpatient appointments. Among those are Hispanic/Latino patients, Spanish and Haitian Creole speaking patients, small cell lung cancer (SCLC) patients, and those patients who have Medicaid, and with late stage lung cancer patients at significantly higher risk (no-shows: OR-5.26 (1.85, 14.95), cancelations: OR-2.49 (1.12, 5.54), combined: OR-12.49 (1.48, 105.46)). Patients in the patient navigation system were also found to be at significantly higher risk of nonadherence (no-shows: OR-3.85 (1.72, 8.65), cancelations: OR-4.13 (1.89, 9.00), combined: OR-5.15 (1.93, 13.72)) than those not in the program. Some patients were also found to be at significantly decreased odds of nonadherence, including those who were: 1000-1999 days post diagnosis (no-shows: OR-0.14 (0.03, 0.59), cancelations: OR-0.20 (0.06, 0.65), combined: OR-0.07 (0.01, 0.64)); 2000-2999 days post diagnosis (no-shows: OR-0.09 (0.01, 0.80), cancelations: OR-0.06 (0.01, 0.50)); aged 71-75 (cancelations: OR-0.25 (0.08, 0.79)). The subset analysis with the patient navigation data yielded no statistically significant results. CONCLUSIONS: The study identified high-risk populations within the total lung cancer population at BMC that should be addressed by the patient navigation program. This study demonstrated that while the program does have its flaws, it is decreasing the odds of nonadherence of many of the high-risk populations.
143

Lung cancer assistant : a hybrid clinical decision support application in lung cancer treatment selection

Şeşen, Mustafa Berkan January 2013 (has links)
We describe an online clinical decision support (CDS) system, Lung Cancer Assistant (LCA), which we have developed to aid the clinicians in arriving at informed treatment decisions for lung cancer patients at multidisciplinary team (MDT) meetings. LCA integrates rule-based and probabilistic decision support within a single platform. To our knowledge, this is the first time this has been achieved in the context of CDS in cancer care. Rule-based decision support is achieved by an original ontological guideline rule inference framework that operates on a domain-specific module of Systematized Nomenclature of Medicine-Clinical Terms (SNOMED-CT), containing clinical concepts and guideline rule knowledge elicited from the major national and international guideline publishers. It adopts a conventional argumentation-based decision model, whereby the decision options are listed along with arguments derived by matching the patient records to the guideline rule base. As an additional feature of this framework, when a new patient is entered, LCA displays the most similar patients to the one being viewed. Probabilistic inference is provided by a Bayesian Network (BN) whose structure and parameters have been learned based on the English Lung Cancer Database (LUCADA). This allows LCA to predict the probability of patient survival and lay out how the selection of different treatment plans would affect it. Based on a retrospective patient subset from LUCADA, we present empirical results on the treatment recommendations provided by both functionalities of LCA and discuss their strengths and weaknesses. Finally, we present preliminary work, which may allow utilising the BN to calculate survival odd ratios that could be translated into quantitative degrees of support for the guideline rule-based arguments. An online version of LCA is accessible on http://lca.eng.ox.ac.uk.
144

Desenvolvimento de nanocápsulas poliméricas contendo erlotinib e avaliação do efeito antitumoral in vitro em células de adenocarcinoma de pulmão / Development of erlotinib-loaded nanocapsules and evaluation of the in vitro antitumor effect in lung adenocarcinoma cells

Bruinsmann, Franciele Aline January 2016 (has links)
Objetivos: Desenvolver e caracterizar nanocápsulas poliméricas contendo erlotinib, bem como avaliar sua atividade antitumoral in vitro em células de adenocarcinoma de pulmão humano. Metodologia: As nanocápsulas contendo erlotinib (0,5 mg.mL-1) foram obtidas pelo método de nanoprecipitação utilizando poli(ε-caprolactona) e óleo de copaíba como parede polimérica e núcleo oleoso, respectivamente. Os parâmetros físico-químicos avaliados foram: diâmetro médio e distribuição de tamanho, índice de polidispersão, potencial zeta, concentração de partículas e pH. Para determinação do teor e eficiência de encapsulação do erlotinib, utilizou-se metodologia validada por CLAE-UV. O estudo de liberação in vitro, utilizando sacos de diálise, foi realizado para obter o perfil de liberação do fármaco a partir das nanocápsulas. As nanocápsulas contendo erlotinib foram avaliadas quanto ao seu potencial de inibir o crescimento, induzir a apoptose, interferir com o ciclo celular e sobrevivência clonogênica de células de adenocarcinoma de pulmão, linhagem A549. Resultados: As nanocápsulas apresentaram diâmetro médio de 171 ± 2 (PDI < 0, 10), potencial zeta de −8,17 ± 2.26 mV, número de partículas por mL de 6,97 ± 0,22 × 1013 e pH de 6,24 ± 0,02. O teor e a eficiência de encapsulação foram próximos de 100%. Com exceção do pH, todos parâmetros mantiveram-se iguais após 30 dias de armazenamento em temperatura ambiente. Observou-se uma liberação controlada do fármaco devido à nanoencapsulação. Os ensaios de citotoxicidade demonstraram que as nanocápsulas contendo erlotinib apresentaram maior atividade antitumoral quando comparado com o fármaco livre. Também foi demonstrado indução de apoptose, pela análise de ciclo celular e marcação por Anexina-V conjugada ao 7-AAD. No ensaio clonogênico, as nanocápsulas contendo erlotinib reduziram 100% o número de colônias formadas. Conclusões: Foram obtidas nanocápsulas com propriedades nanotécnologicas adequadas e capazes de controlar a liberação do erlotinib. Os estudos in vitro na linhagem celular A549 demonstraram aumento no efeito antitumoral e foi demonstrado que o encapsulamento do fármaco é imprescindível para essa melhor atividade. / Purpose: To develop and characterise erlotinib-loaded polymeric nanocapsules and to evaluate its in vitro antitumor activity in human lung adenocarcinoma cells. Methodology: The erlotinib-loaded nanocapsules (0.5 mg.mL-1) were obtained by nanoprecipitation method using poly (ε-caprolactone) and copaiba oil as the polymeric wall and oily core, respectively. The physicochemical parameters evaluated were: mean diameter and size distribution, polydispersity index, zeta potential, particle concentration and pH. An HPLC-UV validated method was used to determine the drug content and encapsulation efficiency. The in vitro release study using dialysis bags was performed to obtain the drug release profile from nanocapsules. The erlotinib-loaded nanocapsules were evaluated regarding their potential to inhibit the growth, induce apoptosis, interfere with the cell cycle and clonogenic survival of lung adenocarcinoma cell (A549). Results: The nanocapsule formulation presented z-average diameter of 171 ± 2 (PDI <0.10), zeta potential value of -8.17 ± 2.26 mV, number of particles per mL of 6.97 ± 0.22 × 1013, and pH value of 6.24 ± 0.02. The drug content and the encapsulation efficiency were nearly 100%. Except for the pH value, all these parameters remained the same after 30 days of storage. A controlled release of the drug was observed due to nanoencapsulation. The cytotoxicity assays demonstrated that the erlotinib-loaded nanocapsules showed higher antitumor activity compared to free drug. Induction of apoptosis was demonstrated by cell cycle analysis and Annexin-V/7AAD staining. In the clonogenic assay, erlotinib-loaded nanocapsules reduced 100% the number of colonies formed. Conclusions: Nanocapsules with appropriate nanotechnological properties and capable of controlling the erlotinib release were obtained. The in vitro studies in the A549 cell line showed an increase in antitumor effect and was demonstrated that the drug encapsulation is essential for this better activity.
145

Desenvolvimento de nanocápsulas poliméricas contendo erlotinib e avaliação do efeito antitumoral in vitro em células de adenocarcinoma de pulmão / Development of erlotinib-loaded nanocapsules and evaluation of the in vitro antitumor effect in lung adenocarcinoma cells

Bruinsmann, Franciele Aline January 2016 (has links)
Objetivos: Desenvolver e caracterizar nanocápsulas poliméricas contendo erlotinib, bem como avaliar sua atividade antitumoral in vitro em células de adenocarcinoma de pulmão humano. Metodologia: As nanocápsulas contendo erlotinib (0,5 mg.mL-1) foram obtidas pelo método de nanoprecipitação utilizando poli(ε-caprolactona) e óleo de copaíba como parede polimérica e núcleo oleoso, respectivamente. Os parâmetros físico-químicos avaliados foram: diâmetro médio e distribuição de tamanho, índice de polidispersão, potencial zeta, concentração de partículas e pH. Para determinação do teor e eficiência de encapsulação do erlotinib, utilizou-se metodologia validada por CLAE-UV. O estudo de liberação in vitro, utilizando sacos de diálise, foi realizado para obter o perfil de liberação do fármaco a partir das nanocápsulas. As nanocápsulas contendo erlotinib foram avaliadas quanto ao seu potencial de inibir o crescimento, induzir a apoptose, interferir com o ciclo celular e sobrevivência clonogênica de células de adenocarcinoma de pulmão, linhagem A549. Resultados: As nanocápsulas apresentaram diâmetro médio de 171 ± 2 (PDI < 0, 10), potencial zeta de −8,17 ± 2.26 mV, número de partículas por mL de 6,97 ± 0,22 × 1013 e pH de 6,24 ± 0,02. O teor e a eficiência de encapsulação foram próximos de 100%. Com exceção do pH, todos parâmetros mantiveram-se iguais após 30 dias de armazenamento em temperatura ambiente. Observou-se uma liberação controlada do fármaco devido à nanoencapsulação. Os ensaios de citotoxicidade demonstraram que as nanocápsulas contendo erlotinib apresentaram maior atividade antitumoral quando comparado com o fármaco livre. Também foi demonstrado indução de apoptose, pela análise de ciclo celular e marcação por Anexina-V conjugada ao 7-AAD. No ensaio clonogênico, as nanocápsulas contendo erlotinib reduziram 100% o número de colônias formadas. Conclusões: Foram obtidas nanocápsulas com propriedades nanotécnologicas adequadas e capazes de controlar a liberação do erlotinib. Os estudos in vitro na linhagem celular A549 demonstraram aumento no efeito antitumoral e foi demonstrado que o encapsulamento do fármaco é imprescindível para essa melhor atividade. / Purpose: To develop and characterise erlotinib-loaded polymeric nanocapsules and to evaluate its in vitro antitumor activity in human lung adenocarcinoma cells. Methodology: The erlotinib-loaded nanocapsules (0.5 mg.mL-1) were obtained by nanoprecipitation method using poly (ε-caprolactone) and copaiba oil as the polymeric wall and oily core, respectively. The physicochemical parameters evaluated were: mean diameter and size distribution, polydispersity index, zeta potential, particle concentration and pH. An HPLC-UV validated method was used to determine the drug content and encapsulation efficiency. The in vitro release study using dialysis bags was performed to obtain the drug release profile from nanocapsules. The erlotinib-loaded nanocapsules were evaluated regarding their potential to inhibit the growth, induce apoptosis, interfere with the cell cycle and clonogenic survival of lung adenocarcinoma cell (A549). Results: The nanocapsule formulation presented z-average diameter of 171 ± 2 (PDI <0.10), zeta potential value of -8.17 ± 2.26 mV, number of particles per mL of 6.97 ± 0.22 × 1013, and pH value of 6.24 ± 0.02. The drug content and the encapsulation efficiency were nearly 100%. Except for the pH value, all these parameters remained the same after 30 days of storage. A controlled release of the drug was observed due to nanoencapsulation. The cytotoxicity assays demonstrated that the erlotinib-loaded nanocapsules showed higher antitumor activity compared to free drug. Induction of apoptosis was demonstrated by cell cycle analysis and Annexin-V/7AAD staining. In the clonogenic assay, erlotinib-loaded nanocapsules reduced 100% the number of colonies formed. Conclusions: Nanocapsules with appropriate nanotechnological properties and capable of controlling the erlotinib release were obtained. The in vitro studies in the A549 cell line showed an increase in antitumor effect and was demonstrated that the drug encapsulation is essential for this better activity.
146

Avaliação da mudança de padrão histológico, idade e gênero em pacientes com neoplasia pulmonar submetidos a tratamento cirúrgico nos últimos 25 anos

Tsukazan, Maria Teresa Ruiz January 2013 (has links)
Objetivo: O câncer de pulmão é a primeira causa de morte relacionada ao câncer quando considerados ambos os sexos. Os grandes esforços para a redução do tabagismo e para a introdução do filtro de cigarro mudaram a epidemiologia do câncer de pulmão. Em países desenvolvidos, a ascensão do adenocarcinoma e o declínio do epidermoide são de notório conhecimento. Outra característica é o aumento da incidência da doença entre mulheres. Um entendimento melhor da atual epidemiologia do câncer de pulmão é necessário para o desenvolvimento de estratégias de saúde pública de prevenção, diagnóstico e tratamento. Métodos: Análise retrospectiva de todos os pacientes com CPNPC tratados com ressecção pulmonar entre 1986 e 2010 em um hospital universitário do Sul do Brasil. As análises foram divididas em três períodos: 1986-1990, 1991-2000 e 2001-2010. O mesmo grupo de patologistas realizou o diagnóstico, e os estágios foram atualizados para a nova classificação da IASLC, 7ª edição. Todas as análises foram realizadas utilizando o programa SAS, versão 13. Resultados: Foram estudados 817 pacientes submetidos à ressecção pulmonar por CPNPC entre 1986 e 2010. Setenta por cento eram homens, média de idade de 61,4 anos, 44,2% carcinoma epidermoide e 40% adenocarcinoma, 26,7% estágio IIIA. A proporção de mulheres apresentou um aumento de 22% no primeiro período para 36% na última década. A idade média no momento da cirurgia era de 52,7 anos para mulheres e 57,3 para homens no primeiro período, e 60,1 para mulheres e 63,9 para homens no último período (p<0.001). A proporção de carcinoma epidermoide modificou de 49,1% inicialmente para 38,7% no último período (p=0.017). Em comparação, a prevalência do adenocarcinoma cresceu de 35,4% para 39,6% e, mais recentemente, para 41,2%. Em relação ao número total de pessoas acometidas pela doença, mulheres com adenocarcinoma representavam 9,4% no primeiro período, 12,5% no segundo e 16,8% no último período. Pacientes com estágio IIIA representavam 27,9% na última década. O tipo de cirurgia predominante foi a lobectomia. A pneumonectomia foi o procedimento cirúrgico em 21,9%, 18,8% e 16,8% dos casos em cada período, em ordem crescente, respectivamente (p<0.03). Conclusão: Neste estudo de pacientes no Sul do Brasil, a análise de gênero demonstrou que a taxa de câncer de pulmão entre as mulheres está aumentando nas últimas três décadas, mas ainda não chegou a ultrapassar a taxa masculina. A proporção de adenocarcinoma em mulheres aumentou. O significativo declínio da quantidade proporcional de pneumonectomia provavelmente reflete a mudança da indicação e técnica cirúrgica. A idade média de pacientes submetidos a tratamento cirúrgico aumentou tanto para homens quanto para mulheres, mas não alcançou a média de países desenvolvidos de 71 anos. A mudança da proporção do tipo histológico e de mulheres está de acordo com os dados de países desenvolvidos. / Objective: Lung cancer is the leading cause of cancer-related death worldwide when considering both genders. The great effort to reduce smoking and to introduce the usage of cigarette filter has changed lung cancer epidemiology. In developed countries, the increasing incidence of adenocarcinoma and the decrease of squamous cell carcinoma are well known. Other characteristic reported is the rising number of women with the disease. Better understanding of current lung cancer epidemiology is necessary for the appropriate design of public health strategies for prevention, diagnosis and treatment. Methods: Retrospective analysis of all patients with non-small cell lung cancer (NSCLC) treated with lung resection between 1986 and 2010 in a university hospital of Southern Brazil. Analysis was divided in three periods: 1986-1990, 1991-2000 and 2001-2010. The same pathology group performed histological diagnosis and all staging was updated according to the new IASLC, 7th edition. All analyses were performed using the SAS program, version 13. Results: We studied 817 patients who underwent lung resection for NSCLC from 1986 to 2010. Seventy percent were males, average age 61.4 years old, 44.2% squamous cell carcinoma and 40% adenocarcinoma, 26.7% stage IIIA. The female proportion increased from 22% in the first period to 36% in the last decade. Mean age at surgery treatment was 52.7 years old for women and 57.3 years old for men in the first period, and 60.1 for women and 63.9 for men in the last period (p<0.001). The proportion of squamous cell changed from 49.1% initially to 38.7% in the last period (p=0.017). In comparison, the adenocarcinoma prevalence increased from 35.4% to 39.6% and, most recently, to 41.21%. Of the total NSCLC patients, females with adenocarcinoma represented 9.4% in the first period, 12.5% in the second and 16.8% in last period. Patients with stage IIIA represented 27.9% in the last decade. Lobectomy was the predominant type of surgery. Pneumonectomy was the surgical procedure in 21.9%, 18.8% and 16.8% of the cases in each period, respectively (p<0.03). Conclusions: In this cohort of patients in Southern Brazil, gender analysis shows that rates of lung cancer in females are rising over the last three decades, but have not surpassed men rates. The proportion of adenocarcinoma in females has increased. The significant decrease of pneumonectomy rates probably reflects changes on surgical management techniques and indication. The mean age of patients undergoing surgical treatment has increased for both men and women, but has not reached the average age reported in developed countries, 71 years old. The histological and gender findings for lung cancer are in accordance with the data of developed countries.
147

Determinantes moleculares de resposta e resistencia aos inibidores da tirosina quinase (TKI) em pacientes com carcinoma de pulmão não pequenas celulas (CPNPC) com mutações no gene do recptor do fator de crescimento epidermico (EGFR) / Molecular determinants of response and resistance to tyrosine kinase inhibitors (TKIs in patients with non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) gene mutation

Costa, Daniel Botelho 12 August 2018 (has links)
Orientador: Lair Zambon / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-12T08:23:12Z (GMT). No. of bitstreams: 1 Costa_DanielBotelho_D.pdf: 9890444 bytes, checksum: 90e3892529ddea892b184c2ca660ac69 (MD5) Previous issue date: 2008 / Resumo: A maioria dos carcinomas de pulmão não pequenas células (CPNPC) em estádios avançados com mutações ativadoras (deleções do exon 19 ou a mutação L858R do exon 21) do receptor do fator de crescimento epidérmico (EGFR) respondem inicialmente, aos medicamentos gefitinib e erlotinib, que são inibidores da tirosina quinase (TKIs) do EGFR. Porém em uma média de 6-12, meses esses tumores desenvolvem resistência adquirida aos TKIs do EGFR. Dois mecanismos de resistência ao gefitinib/erlotinib explicam porque os CPNPC com mutações do EGFR se tornam resistentes aos TKIs: mutações de resistência secundária e um sistema de "troca de oncogenes". A mutação T790M-EGFR secundária ocorre em 50% dos pacientes com mutação no EGFR com resistência adquirida aos TKIs do EGFR, e em in vitro esta mutação T790M-EGFR inativa a hipersensitividade das mutações ativadoras do EGFR ao gefitnib ou erlotinib. Outras mutações de resistência secundárias (D761Y, L747S, A854T) são raras. Um outro mecanismo de resistência é a amplificação adquirida do oncogene MET, que ocorre em mais ou menos 20% do pacientes resistentes ao gefitinib/erlotinib e, em metade destes casos, em conjunção com T790M. O MET ativa sinais de sinalização que contornam o EGFR inibido, gerando um sistema de "troca de oncogenes" nesses tumores. Esses dados pré-clinicos relevantes aos CPNPCs com o EGFR mutado e resistência ao gefitinib ou erlotinib levaram ao desenvolvimento de experimentos clínicos com novos inibidores do EGFR que inibem "in vitro" a mutação T790M-EGFR (HKI-272, XL-647, BIBW-2992 e PF00299804), e inibidores de MET mais TKIs do EGFR em combinação. Neste trabalho: 1) Agrupamos e resumimos os dados dos experimentos clínicos prospectivos com o gefinitib em pacientes com o EGFR mutado. Mais de 80% dos pacientes com deleções do exon 19 ou a mutação L858R do EGFR tiveram resposta radiográfica, com sobrevivência livre de progressão de 7,7 a 12,9 meses nos estudos identificados, e sobrevivência geral acima de 15 meses; 2) Usamos células CPNPC com mutações do EGFR para identificarmos a molécula pró-apoptótica BIM como o efetor principal da apoptose induzida pelos TKIs do EGFR; 3) Caracterizamos a mutação resistente ao gefinitib EGFR-L858R-L747S, e determinamos que L858R-L747S apresenta um padrão de resistência menos acentuado ao gefitinib do que o observado com L858R-T790M; e 4) Avaliamos os efeitos do erlotinib em pacientes com CPNPC EGFR mutado e resistência ao gefitinib, caracterizando a correlação da resposta radiográfica e clínica com os mecanismos conhecidos de resistência ao TKIs do EGFR (as mutações de resistência secundárias T790M e L747S, e a amplificação do MET). A maioria (mais de 83%) dos pacientes resistentes ao gefitinib tiveram progressões radiográficas nos primeiros 2 a 4 meses de exposição ao erlotinib 150 mg/dia. Isto é consistente com nossas observações pré-clínicas, indicativas de que a maioria dos tumores resistentes ao gefitinib possui predominantemente T790M e/ou amplificações do MET, que são resistentes tanto ao gefitinib quanto erlotinib. Pesquisas pré-clínicas e experimentos clínicos futuros do CPNPC com EGFR mutado têm o potencial de melhorar os resultados do tratamento clínico de pacientes com essas mutações somáticas. / Abstract: Most advanced non-small cell lung cancers (NSCLCs) with activating epidermal growth factor receptor (EGFR) mutations (exon 19 deletions or L858R) initially respond to the EGFR tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib. However, over time (median of 6-12 months) most tumors develop acquired resistance to EGFR TKIs. Intense research in these NSCLCs has identified two major mechanisms of resistance to gefitinib/erlotinib: secondary resistance mutations and "oncogene kinase switch" systems. The secondary T790M mutation occurs in 50% of EGFR mutated patients with TKI resistance, and in vitro this mutation negates the hypersensitivity of activating EGFR mutations. Other secondary resistance mutations (D761Y, L747S, A854T) seem to be rare. The amplification of the MET oncogene is present in 20% of TKI-resistant tumors; however in half of the cases with this "oncogene kinase switch" mechanism the T790M is co-existent. The growing pre-clinical data in EGFR mutated NSCLCs with acquired resistance to gefitinib or erlotinib has spawned the initiation or conception of clinical trials testing novel EGFR inhibitors that in vitro inhibit T790M (HKI-272, XL-647, BIBW-2992 and PF00299804), and MET inhibitors in combination with EGFR TKIs. In this work we: 1) Pooled and summarized data from prospective clinical trials of gefitinib for EGFR mutated patients. More than 80% of patients with exon 19 deletions or the L858R EGFR mutation attained a radiographic response with progression-free survival of 7.7 to 12.9 months in the identified studies, and overall survival exceeding 15 months; 2) Identified the pro-apoptotic molecule BIM as the main effector of EGFR TKI-induced apoptosis using NSCLC cell lines with EGFR mutations; 3) Characterized the L858R-L747S gefitinib-resistant mutation, and demonstrated that L858R-L747S has a partial resistance pattern when compared to L858R-T790M; and 4) Evaluated the effects of erlotinib in EGFR mutated NSCLC with resistance to gefitinib while characterizing the correlation of response and resistance to this approach to the known mechanisms of resistance to EGFR TKIs (the secondary mutations T790M and L747S, and the amplification of MET). Our clinical observation was that the majority (over 83%) of the gefitinib-resistant patients given erlotinib 150 mg/day had radiographic progression within the first 2 to 4 months of exposure. This is consistent with our pre-clinical observations, since we expected gefitinib-resistant tumors to predominantly harbor T790M and/or MET amplification, which are cross-resistant to both gefitinib and erlotinib. Ongoing pre-clinical and clinical research in EGFR mutated NSCLC has the potential to significantly improve the outcomes of patients with these somatic mutations. / Doutorado / Clinica Medica / Doutor em Clínica Médica
148

The effect of nicotine and prostaglandin A2 on the lung cancer cell line NCI-H157

Willemse, Chontrelle January 2009 (has links)
Philosophiae Doctor - PhD / Lung cancer is the most common fatal cancer in terms of both incidence and mortality in the world. The most important cause of lung cancer is exposure to tobacco smoke through active or passive smoking. Nicotine which is a major component of tobacco could be assumed to be a tumour promoter since it had been indicated to stimulate tumour growth. Over expression of Bcl-2 in human lung cancer cells blocked the induction pathways (type I and II) of apoptosis. The increase in Bcl-2 in patients with lung cancer had also been linked to nicotine. In recent years nicotine replacement therapy has become a therapeutic method to treat smoker’s withdrawal symptoms and to advise cancer patients to stop smoking because, numerous cancer patients continue to smoke after their diagnosis. Non small cell lung carcinomas constitutes for approximately 80% of lung cancer cases. However, even with the development and improvement in conventional treatments of surgery, radiation and chemotherapy, the 5 year survival rate for these patients remains less than 15%. Chemoprevention, an approach to control cancer, is the use of specific natural or synthetic substances with the objective of delaying, reversing, suppressing or preventing carcinogenic progression to invasive cancer. A promising tool for chemoprevention against lung cancer could be prostaglandin A2 (PGA2), since it had been shown to have inhibitory effects on various cancer cell growth. The search for more effective agents, or combination therapies that could induce apoptosis in lung cancer are currently under investigation as a therapeutic target for the treatment of lung cancer. In order to elucidate the effect of nicotine and PGA2 on lung cancer cell proliferation in this study, an over view of the following was given;the cell cycle, tubulin, nucleoli, apoptosis, lung cancer, the etiology of cancer with reference to tobacco smoke and nicotine, the nutritional influence on carcinogenesis with reference to essential fatty acids and prostaglandins and chemoprevention.The supplements nicotine and PGA2 were administered to the NCI-H157 lung cancer cell line at the concentrations of 1 mM, 1 μM and 1 nM for nicotine and 5, 10 and 20 μg/ml PGA2. The effect of combinations of nicotine and PGA2 on the proliferation and survival was also tested. 5 μg/ml PGA2 was added to 1 mM, 1 μM and 1 nM nicotine respectively. This was also done for 10 and 20 μg/ml PGA2.These concentrations were administered to the cell culture and exposed for three different time exposures, namely 24, 48 and 72 hours. The objectives were: 1) To determine the effect of nicotine and PGA2 and combinations thereof on the growth(proliferation) of the NCI-H157 cells, where early results indicative of apoptosis lead to the investigation of the influence of nicotine and PGA2 on apoptosis. The effect of nicotine and PGA2 and their combinations on the morphology of interphase and dividing cells, as well as on the morphology of the dying cells were compared and quantified. 2) To study the effects of nicotine and PGA2 and their combinations on the nucleolar organizer region using silver stain. 3) To study the effects of nicotine and PGA2 or combinations thereof on the cytoskeleton (α-tubulin) of the cancer cells with aid of indirect immunofluorescence and to identify apoptotic cells using Hoechst 33342. 4) To determine the effect of nicotine and PGA2 and their combinations on cell cycle progression and apoptosis induction in the transformed cells using flow cytometry (DNA propidium iodide stain, Annexin V and caspase-3).In order to verify the effects of nicotine and PGA2 and their combinations on protein synthesis, SDS-PAGE and immunoblotting was employed.This study indicated the anti-apoptotic effects of nicotine. It maintained and stimulated cell proliferation of the NCI-H157 cell line. PGA2 demonstrated that it has a pro-apoptotic effect. The concentrations of 10 and 20 μg/ml PGA2 decreased cell proliferation and demonstrated its pro-apoptotic effects more effectively than 5 μg/ml PGA2. The combination of 10 and 20 μg/ml PGA2 and nicotine (1 mM, 1 μM and 1 nM) also showed a more pronounced induction of apoptosis than 5 μg/ml PGA2 and nicotine (1 mM, 1 μM and 1 nM). PGA2 therefore demonstrated that it blocked the mitogenic and anti-apoptotic effects of nicotine. With its pro-apoptotic effects, PGA2 could therefore be assumed to be a chemopreventive agent. However,it was evident that apoptotic induction was stimulated via both a dependent and an independent caspase-3 pathway and therefore further investigation is needed to indicate which pathway was activated. This study identified PGA2 as a chemopreventive agent for in vitro conditions; however, further studies are also needed to investigate the effect of in vivo conditions.
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Identification of potential biomarkers in lung cancer as possible diagnostic agents using bioinformatics and molecular approaches

Ahmed, Firdous January 2015 (has links)
>Magister Scientiae - MSc / Lung cancer remains the leading cause of cancer deaths worldwide, with the majority of cases attributed to non-small cell lung carcinomas. At the time of diagnosis, a large percentage of patients present with advanced stage of disease, ultimately resulting in a poor prognosis. The identification circulatory markers, overexpressed by the tumour tissue, could facilitate the discovery of an early, specific, non-invasive diagnostic tool as well as improving prognosis and treatment protocols. The aim was to analyse gene expression data from both microarray and RNA sequencing platforms, using bioinformatics and statistical analysis tools. Enrichment analysis sought to identify genes, which were differentially expressed (p < 0.05, FC > 2) and had the potential to be secreted into the extracellular circulation, by using Gene Ontology terms of the Cellular Component. Results identified 1 657 statically significant genes between normal and early lung cancer tissue, with only 1 gene differentially expressed (DE) between the early and late stage disease. Following statistical analysis, 171 DE genes selected as potential early stage biomarkers. The overall sensitivity of RNAseq, in comparison to arrays enabled the identification of 57 potential serum markers. These genes of interest were all downregulated in the tumour tissue, and while they did not facilitate the discovery of an ideal diagnostic marker based on the set criteria in this study, their roles in disease initiation and progression require further analysis.
150

DISPARITIES IN STAGE-APPROPRIATE THERAPY FOR RESECTABLE NON-SMALL CELL LUNG CANCER IN KENTUCKY

Martin, Jeremiah T. 01 January 2017 (has links)
Lung cancer (NSCLC) is the leading cause of cancer related mortality. Lung cancer screening aims to detect treatable cancers, however survival advantage will only be seen with early and appropriate stage-directed therapy. This study aims to understand recent rates of therapy for early-stage lung cancer in Kentucky, and to explore potential sources of disparities in treatment and outcomes. A Kentucky Cancer Registry query was performed of all NSCLC cases treated in the state from 2005-2014. Of 39,763 lung cancer patients, 10,622 were clinically operable. Of these, overall 40% did not receive surgery, while 16% did not receive any stage-appropriate local therapy. Wide variation was noted in rates of surgery and local therapy at the county level. Increased age, non-private insurance status, non-white race, male gender, and non-married status were less likely to receive surgery. Median survival in patients who underwent surgery was 59.1 months vs 16 months (p< 0.001). Appropriate stage-directed local therapy is a very important factor in survival of patients with early stage NSCLC. County-level variation in rates of therapy need further study. Demographic factors continue to drive disparities in therapy and outcomes in Kentucky and should inform health policy and ongoing research and education efforts.

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