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Caracterização dos efeitos antitumorais do guaraná sobre modelo murino de células tronco cancerosas / Characterization of the antitumor effects of guarana on murine model of cancer stem cellsArina Lázaro Rochetti 16 December 2015 (has links)
O câncer de pulmão está entre os tipos de câncer com maiores índices de mortalidade no mundo. Na década de 90, houve a descoberta de populações de células tumorais com características de células-tronco e implicou na hipótese das células-tronco cancerosas (CTCs). Se a hipótese das CTCs for correta, a recorrência/recidiva dos cânceres é gerada por uma porcentagem de células (CTCs) que prolifera pouco e é resistente a quimioterapia convencional. Desta forma, a busca por novos alvos terapêuticos que tenham como alvo estas CTCs tem enorme implicação no desenvolvimento de novos fármacos ou modalidades terapêuticas contra o câncer. O guaraná (Paullinia cupana Mart var. sorbilis) tem demonstrado efeitos promissores sobre o câncer, em especial efeitos quimiopreventivos e antineoplásicos. Portanto, objetivando-se neste projeto avaliar a presença de CTCs a partir de células tumorais de pulmão de camundongo, onde se possa conseguir rapidamente uma alta porcentagem deste tipo celular para posteriores estudos, além de avaliar os efeitos do extrato etanólico do guaraná e de suas frações butanólica e aquosa, sobre as células tumorais e em especial verificar os efeitos sobre a população rica em CTCs, onde foi possível observar a presença de possíveis CTCs, a partir de cultivo de células tumorais de pulmão de camundongo, como também que o guaraná apresentou um efeito sobre estas possíveis CTCs devido a diminuição da expressão dos genes ABCG2 e ALDH1a1. / Lung cancer is among the cancers with the highest mortality rates in the world. In the 90\'s, there was the discovery of tumor cell populations with stem cell characteristics implied in the case of cancer stem cells (CSCs). If the hypothesis is correct CSCs of the recurrence / relapse of cancers is generated by a percentage of cells (CSCs) that growth low and are more resistant to conventional chemotherapy. Thus, the search for new therapeutic targets that target these CSCs has huge implications in developing new drugs or therapeutic approaches against cancer. Guarana (Paullinia cupana Mart var. Sorbilis) has shown promising effects on cancer, especially chemopreventive and anticancer effects. Therefore, the objective in this project is to evaluate the presence of CSCs from tumor cells of mouse lung, where it can quickly get a high percentage of this cell type for further studies and to evaluate the effects of ethanol extract of guarana and its butanol and aqueous fractions on tumor cells and in particular to verify the effect on the population rich in CSCs, where it was possible to observe the possible presence of CSCs from cultivation of tumor cells from mouse lung, as well as guarana presented an effect on these CSCs possible to decreased expression of ABCG2 and ALDH1a1 genes.
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Investigação das quinases Aurora A e Aurora B na tumorigenicidade mediada pelo oncogene KRAS / Investigation of Aurora kinases A and B in KRAS-induced lung tumorigenesisEdmilson Ozorio dos Santos 08 February 2017 (has links)
O câncer de pulmão é a principal causa de morte relacionada ao câncer no mundo. Mutações em KRAS são altamente prevalentes no câncer e têm sido diretamente associadas ao processo tumorigênico. Apesar disso, até hoje todas as terapias visando inibir KRAS diretamente falharam e a caracterização de alvos indiretos, importantes para a oncogênese mediada por KRAS, é fundamental para o desenvolvimento de novas terapias contra o câncer de pulmão. Nós mostramos previamente que as quinases Aurora A (AURKA) e B (AURKB) são alvos a jusante de KRAS, importantes para o crescimento, viabilidade e oncogenicidade de linhagens celulares derivadas de tumores pulmonares mediados por KRAS. Aqui, nós aprofundamos os nossos estudos para melhor caracterizar AURKA e AURKB como potenciais alvos terapêuticos no câncer de pulmão. Os objetivos deste trabalho foram (1) investigar o mecanismo de perda de viabilidade induzido pela inibição de AURKA e/ou AURKB; (2) avaliar como a inibição de AURKA e/ou AURKB afeta propriedades oncogênicas relacionadas à agressividade tumoral; e (3) como a inibição destas quinases afeta o crescimento tumoral in vivo. Para tanto, nós utilizamos dois modelos celulares: (1) células A549 e H358, que apresentam mutações em KRAS, geneticamente modificadas para a expressão estável e induzível de shRNAs contra AURKA ou AURKB, e (2) células tumorais H1703, que não apresentam mutações em KRAS, geneticamente modificadas para a expressão induzível de KRASG12V, tratadas ou não com inibidores farmacológicos das quinases Aurora. A inibição farmacológica ou por interferência de RNA de AURKA e/ou AURKB em células H358 e A549 reduziu a proliferação celular, sendo esta inibição acompanhada de anomalias mitóticas, além de aneuploidia e poliploidia. A inibição destas quinases também induziu morte celular in vitro, tanto em mitose, quanto em interfase. Mais interessantemente, a inibição farmacológica dual de AURKA e AURKB induziu morte celular in vitro em células H1703, somente na presença de KRASG12V, indicando que a inibição das quinases Aurora afeta preferencialmente células portadoras de mutações em KRAS. Além disso, a inibição de AURKA e/ou AURKB reduziu propriedades malignas celulares relacionadas à agressividade tumoral, como migração, invasão e adesão. Finalmente, a inibição de AURKA por RNA de interferência em células A549 também reduziu a formação de tumores in vivo. Entretanto, como a inibição destas quinases levou a anomalias mitóticas e à instabilidade genética, nós resolvemos investigar se a inibição de TPX2, um substrato e ativador de AURKA, poderia ser uma abordagem alternativa para inibir esta via em câncer de pulmão induzido por KRAS. Primeiramente, nós observamos nos nossos modelos celulares que KRAS regula positivamente a expressão de TPX2. Além disso, a inibição de TPX2 em células pulmonares portadoras de KRAS oncogênica reduziu a viabilidade e proliferação celulares e induziu morte celular. Mais interessantemente, esses efeitos ocorreram preferencialmente em células que expressam KRAS oncogênica. Em conclusão, nossos resultados apoiam a hipótese de que a ativação de AURKA/TPX2 e AURKB por KRAS são eventos importantes no câncer de pulmão e sugerem a inibição destas vias, possivelmente em combinação com outras terapias citotóxicas, como uma nova abordagem terapêutica para o câncer de pulmão induzido por KRAS. / Lung cancer is the leading cause of cancer-related deaths worldwide. KRAS mutations are widespread in lung cancer and have been causally linked to tumorigenesis. Nonetheless, therapies targeting KRAS directly have so far failed and characterization of indirect KRAS targets, which play important roles in KRAS-mediated oncogenesis, is crucial for the development of new therapies for lung cancer. We have previously shown that mitotic kinases Aurora A (AURKA) and B (AURKB) are downstream targets of oncogenic KRAS, important for the growth, viability, and oncogenicity of KRAS-transformed lung cancer cell lines. Here, we studied these kinases more in depth in order to better characterize them as potential therapeutical targets for KRAS-induced lung cancer. The aims of this study were (1) to investigate the mechanism leading to loss of viability upon AURKA and/or AURKB targeting; (2) to evaluate how AURKA and/or AURKB inhibition affects malignant properties associated with tumor aggressiveness; and (3) to determine whether AURKA and/or AURKB inhibition reduces KRAS-induced tumor growth in vivo. For that purpose, we used two cell-based models: (1) KRAS mutant A549 and H358 cells with stable and inducible shRNA-mediated knockdown of AURKA or AURKB, and (2) KRAS wildtype H1703 tumor cell lines, genetically engineered to inducibly express oncogenic KRASG12V treated or not with Aurora kinase pharmacological inhibitors. Targeting AURKA and/or AURKB pharmacologically or by RNA interference in H358 and A549 cells led to decreased cell proliferation, which was accompanied by mitotic abnormalities, leading to aneuploidy and hyperploidy. Aurora kinase targeting also induced cell death in vitro, both during mitosis and interphase. More importantly, AURKA and AURKB inhibition with a dual pharmacological inhibitor in H1703 cells induced cell death in vitro, but only in the presence of KRASG12V, indicating that Aurora kinase targeting affects preferentially lung cells harboring oncogenic KRAS. Furthermore, AURKA and/or AURKB targeting reduced malignant properties associated with tumor aggressiveness, such as cell migration, invasion and adhesion. Finally, AURKA targeting by RNA interference in A549 cells also reduced growth of xenograft tumors in vivo. Nonetheless, since Aurora targeting was associated with mitotic abnormalities and genetic instability, we decided to investigate if targeting TPX2, a substrate and an activator of AURKA, could constitute an alternative approach to targeting this pathway in KRAS-induced lung cancer. First, using our cell-based models, we determined that KRAS positively regulates TPX2 expression. In addition, TPX2 inhibition by RNA interference in KRAS-positive lung cells reduced cell viability and proliferation and induced cell death. Finally, these effects occurred preferentially in cells harboring oncogenic KRAS. In conclusion, our results support the hypothesis that activation of AURKA/TPX2 and AURKB by KRAS are important events in lung cancer and suggest inhibition of these pathways, possibly in combination with other cytotoxic therapies, as a new approach for KRAS-induced lung cancer therapy.
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Estudo da expressão de citocinas no microambiente tumoral em pacientes com neoplasias pulmonares e sua correlação com a presença de macrófagos e células dendríticas. / Study of the expression of cytokines in the tumor microenvironment in lung cancer patients and their correlation with the presence of macrophages and dendritic cells.Renato Brito Baleeiro 13 December 2007 (has links)
Células dendríticas (DCs) são centrais na indução da resposta imune e o desvio de sua diferenciação para macrófagos, no microambiente tumoral pode ser um mecanismo de escape do tumor frente à resposta imune. Assim, o objetivo deste projeto foi comparar, entre tecido neoplásico e não-neoplásico, a freqüência de DCs, macrófagos e mastócitos e da produção in situ das citocinas IL-4 e TNF-<font face=\"symbol\">a. Nesta análise observou-se maior quantidade de DCs (CD1a+ ou S100+), macrófagos (CD68+), mastócitos (azul de toluidina+) e células produtoras de TNF-<font face=\"symbol\">a no tumor do que no tecido pulmonar. No tecido pulmonar encontrou-se maior freqüência de células positivas para IL-4, assim como, entre células dissociadas de tecido fresco, observou-se maior freqüência de DCs maduras. Identificou-se também a expressão, por células tumorais ou do estroma pulmonar, do marcador CD83, característico de DCs ativadas, em 10 de 11 pacientes. O sobrenadante de cultura destas células CD83+ inibiu a ativação de linfócitos por DCs alogenêicas, mas esta atividade foi suprimida por anticorpos anti-CD83. / Dendritic cells (DCs) play a crucial role in the immune response and the deviation of its differentiation to macrophages in the tumor microenvironment may be a mechanism of escape of tumor from immune response. Thus, the aim of this project was to compare between affected and non-affected lung, the frequency of DCs, macrophages and mast cells and production in situ of IL-4 and TNF-<font face=\"symbol\">a. In this analysis, we observe higher amount of DCs (CD1a+ and S-100+), macrophages (CD68+), mast cells (toluidine blue+) and cells producing TNF-<font face=\"symbol\">a in the tumor than non-affected lung. In lung, we found higher frequency of cells IL-4+ and in lung digests we observed higher amount of mature DCs. We also identified the expression by tumor or stroma cells the CD83, present in activated DCs, in 10 of 11 patients. The supernatant of such cells CD83+ inhibited the activation of lymphocyte by alogeneic DCs, but this effect was decreased by anti-CD83.
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Câncer de pulmão: avaliação do emprego de medidas paliativas em um hospital terciário / Assessment of palliative care in a tertiary hospitalRenata dos Santos 28 June 2011 (has links)
Cuidado Paliativo é cuidado ativo total de pacientes cuja doença não é mais passível de responder a tratamento curativo. Almeja-se controlar a dor e outros sintomas e tratar de problemas de ordem psicológica, social e espiritual. O objetivo é melhorar a qualidade de vida do paciente e de seus familiares, de acordo com a definição da Organização Mundial de Saúde. Esta abordagem, portanto, é de responsabilidade de uma equipe multidisciplinar que enfoca a pessoa doente e o alívio integral do sofrimento. A vida é afirmada, e a morte é encarada como natural, não sendo antecipada nem postergada. Dada a importância desta difícil tarefa, é crucial que o atendimento seja de boa qualidade, e para tanto é necessário utilizar indicadores de qualidade do Cuidado Paliativo. No caso do câncer incurável, os indicadores de qualidade do Cuidado Paliativo incluem a avaliação da qualidade de vida, do controle dos sintomas e da satisfação do paciente e da família com o cuidado. Além desses indicadores, fundamentais, porém de difícil obtenção, existem aqueles obtidos com base em dados administrativos. Dentre estes, os mais frequentes são a fração de pacientes encaminhados ao Cuidado Paliativo, a porcentagem de pacientes que receberam quimioterapia no final da vida e fração de óbitos ocorridos na unidade de cuidados paliativos ou no domicílio. Numa situação ideal, espera-se que a grande maioria dos pacientes seja encaminhada à unidade de cuidados paliativos e que o óbito ocorra na própria unidade ou na residência do paciente, e não em unidades de emergência, na terapia intensiva ou em enfermarias gerais. Quanto à quimioterapia no final da vida, pode ser um indicador de tratamento inapropriadamente agressivo. Cabe ressaltar, contudo, que estes indicadores não estão universalmente validados. Levando-se em consideração esta limitação, estudos em outros países concluem que o Cuidado Paliativo é subutilizado e introduzido tardiamente no curso da doença. Este cenário negativo inclui o uso agressivo da quimioterapia no final da vida. Um diagnóstico de câncer de pulmão metastático geralmente implica em um curto tempo de vida com uma carga elevada de sintomas. Nesta situação, a quimioterapia parece ser vantajosa, prolongando a vida e melhorando a sua qualidade, quando se avalia esse grupo de pacientes de uma forma global. Em um paciente individual, porém, há de ser levar em conta seu estado funcional, bem como as comorbidades e a toxicidade do tratamento. Também são importantes aspectos da comunicação médico-paciente quanto ao prognóstico e os benefícios esperados da quimioterapia. Neste contexto, a necessidade da visão global do paciente e do controle de sintomas implica no Cuidado Paliativo, isoladamente ou associado ao tratamento oncológico específico. Resolvemos, portanto investigar, retrospectivamente, indicadores de qualidade, com base em dados administrativos, do Cuidado Paliativo em pacientes portadores de câncer de pulmão não pequenas células (CPNPC) metastático atendidos na Fundação Pio XII, Hospital de Câncer de Barretos, cujo óbito tenha ocorrido entre Janeiro de 2003 e Janeiro de 2005. Os indicadores escolhidos foram a porcentagem de pacientes encaminhados à unidade de Cuidados Paliativos, o local do óbito e a porcentagem de pacientes que receberam quimioterapia no último mês de vida.No total foram revisados 275 prontuários, destes 36 estavam incompletos, sendo elegíveis 239 pacientes para as análises. A data do óbito foi detectada em 218 pacientes, sendo o atestado de óbito disponível em 166 pacientes. A maioria dos pacientes (75,3%) tinha baixa escolaridade, analfabetos ou com o ensino fundamental incompleto. A cor era branca em 78,6% dos casos e a idade mediana era de 64 anos (intervalo 31-90 anos). O hábito do tabagismo foi detectado em 77,4% dos pacientes. Quanto às características clínicas, notamos que o escore de estado funcional Karnofsky (KPS) não foi registrado em aproximadamente metade dos pacientes. Naqueles em que havia registro, 58,8% apresentavam estado funcional preservado (KPS >70%). Os sítios de metástase mais frequentes foram o fígado (39,3%), ossos (22,6%) e cérebro (19,7%). Em relação aos sintomas, os mais frequentes foram dor (47,6%) e dispnéia (34,3%), sendo os opiódes usados por 36,8% dos pacientes. O tratamento oncológico consistiu em cirurgias (6,5%), radioterapia (61,9%) e quimioterapia (44,7%). Os esquemas mais utilizados (85,9%) em primeira linha foram as combinações baseadas em platina, com uma mediana de três ciclos administrados por paciente. A quimioterapia de segunda linha foi aplicada em 9,0% dos pacientes.Quanto aos indicadores de qualidade do Cuidado Paliativo, somente 104/239 (43,5%) dos pacientes foram encaminhados à unidade de cuidados paliativos. Nestes o óbito ocorreu em 38 ± 58 (media ± desvio padrão) dias, sendo uma fração importante destes, 20/104 (19,2%), em menos de quatro dias. Num modelo por análise de regressão logística, o sexo feminino, a menor escolaridade, a realização de radioterapia, a ausência de dor, e a ausência do uso de quimioterapia foram preditivos do encaminhamento à unidade (p=0,04; 0,03; 0,01; 0,03; 0,05), respectivamente. A quimioterapia foi aplicada em 46 dos 239 pacientes (19,2%) no último mês de vida, sendo a ausência de realização de radioterapia (p= 0,02) o único fator preditivo, pela análise de regressão logística. Em relação ao local do óbito, este ocorreu no domicílio ou na unidade de cuidados paliativos em somente 119/218 (55,5%) dos casos, sendo os restantes em enfermarias clínicas, na emergência ou em unidades de terapia intensiva. A sobrevida global foi de 4,4 ± 0,3 (media ± desvio padrão) meses após o diagnóstico da metástase, pela análise de Kaplan-Meier.Em conclusão, este grupo de pacientes portadores de CPNPC metastático não se beneficiou plenamente do Cuidado Paliativo e uma fração significativa destes foi submetida a tratamento agressivo no final da vida. A dificuldade em estimar-se o prognóstico e fatores culturais ligados a negação da finitude humana e exaltação da tecnologia, além de barreiras na comunicação médico-paciente precisam ser melhor estudados / Palliative Care is the total active care of patients whose disease is no longer amenable to curative measures. Control of pain and other symptoms is a priority, and psychological, social and spiritual issues are taken into consideration. The goal is to improve the quality of life of patients and of their families, according to the World Health Organization definition. Thus a team approach is necessary, with focus on the individual as a whole and aiming to ease suffering. Life is affirmed and death is seen as natural and neither hastened nor postponed. Given the importance of this hard task, quality of care should be optimal. In relation to incurable cancer, Palliative Care quality measures include the evaluation of the quality of life, of symptom control and of patient´s and family satisfaction with care. In addition to these measures, which are fundamental but difficult to obtain, there are those obtained from administrative data. Among these, the most frequent are the percentage of patients who were referred to the palliative care unit, the percentage of patients who were treated with chemotherapy near the end of life and the fraction of patients who died in their homes or in the palliative care unit. In an ideal setting, the great majority of these patients should be referred to Palliative Care, the place of death should be the Palliative Care unit or the patients´ homes. Death should not occur in emergency rooms, intensive care units or acute care inpatient units. Regarding chemotherapy administration near the end of life, that may imply in an inappropriately aggressive treatment. However, these quality measures lack universal validation. With this caveat in mind, studies conducted in other countries concluded that Palliative Care is underutilized and introduced late in the disease course. This negative scenario includes the aggressive use of chemotherapy near the end of life.A diagnosis of metastatic lung cancer usually implies in a short survival and a heavy symptom burden. Chemotherapy may prolong survival and improve the quality of life, when this population is analyzed as a whole. In the individual patient, however, performance status, comorbidities and treatment toxicity must be taken into consideration. Patient-doctor communication issues that deal with prognosis and the expected benefits of chemotherapy are also critical. In this context, to see the patient as a whole and symptom control demands Palliative Care, alone or in addition to specific anti-cancer treatment.Thus, we decided to retrospectively investigate administrative based quality measures of Palliative Care in metastatic non small cell lung cancer patients (NSCLC), who were managed at Fundação Pio XII, Hospital de Câncer de Barretos, and who died from January 2003 to January 2005. The measures that were chosen were the percentage of patients who were referred to the palliative care unit, the place of death and the percentage of patients who were treated with chemotherapy in the last month of life. A total of 275 patient charts were reviewed, 36 were incomplete, thus 239 patients were eligible for the analysis of clinical and treatment characteristics. The time of death was available for 218 patients, and the death certificate was available for 166 patients. Most (75,3%) patients had a low educational level, being illiterate or with incomplete elementary school. Patients were white (78,6%) with median age of 64 years (range 31-90 years). Smoking history was positive in 77,4% patients. In relation to the clinical characteristics, Karnofsky (KPS) performance status score was not recorded in approximately half of the patient group. In those that it was available, 58,8% presented with preserved functional status do (KPS>70). The most frequent metastatic sites were liver (39,3%), bones (22,6%) and brain (19,7%). The most frequent symptoms were pain (47,6%) and shortness of breath (34,3%); opioids were used by 36,8% dos patients. Cancer treatment was surgery (6,5%), radiotherapy (61,9%) and chemotherapy (44,7%). The most commonly used protocols in first line (85,9%) were platinun based combination chemotherapy, with a median of three cycles per patient. Second line chemotherapy was administered to 9,0% of patients.In relation to the Palliative Care quality measures, only 104/239 (43,5%) patients were referred to the unit, 38±58 days before death, being a significant minority, 20/104 (19,2%) referred late, four or less days before death. In a logistic regression model, female gender, low educational level, radiotherapy, lack of pain and lack of chemotherapy administration were predictive of referral to the unit (p=0,04; 0,03; 0,01; 0,03; 0,05), respectively. Chemotherapy was administered to a significant minority 46/239 (19,2%) of patients in the last month of life. In this case, the lack of radiotherapy was the only predictive variable by logistic regression analysis (p= 0,02). The place of death was in the patients´ homes or in the Palliative Care unit in only 119/218 (55,5%) cases, being the rest in acute care beds, emergency rooms or intensive care units. The overall survival after the diagnosis of metastatic disease was 4,4 ± 0,3 months, by Kaplan-Meier analysis.In conclusion, our NSCLC patients did not fully benefit from Palliative Care and a significant fraction of these patients were submitted to aggressive care near the end of their lives. The difficulty in estimating patients´ prognosis and cultural factors linked to the denial of human finitude and technicism, as well as patient- doctor communication barriers should be explored in future studies
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Atividade Física e Câncer de Pulmão: um estudo caso controle / Physical Activity and Lung Cancer: a case control studyBrizio, Maria Laura Dutra Rezem 27 February 2013 (has links)
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Previous issue date: 2013-02-27 / The aim of this study was to investigate the association between physical activity (PA) engagement throughout life and the incidence of lung cancer (CA) in southern Brazil. A case control study was carried out. Both cases and controls responded to a questionnaire containing questions about sociodemographics , gender, age and skin color, anthropometric information, marital status, education, smoking and family history of CA. Physical activity was measured using the Lifetime Physical Activity Questionnaire. We studied a total of 249 individuals (81 cases and 168 controls). In the crude analysis, active commuting increased the odds for CA (p=0.01) and sports activities resulted in non-significant protection (p=0.05). In the adjusted analysis, the occupational PA (p=0,009) and lifetime PA (p=0.02) were associated to lower odds of CA, while active commuting (p=0.03) and household activities (p=0.01) were associated with increased odds of CA. For this reason, it s extremely important to encourage the practice of PA since childhood, because considering the consistent evidence on the importance of PA in the prevention of many diseases in adulthood, including CA, its encouragement at early ages may represent a strategy to control physical inactivity worldwide and hence reduce the epidemic of chronic diseases / O objetivo deste estudo foi verificar a associação entre a prática de Atividades Físicas (AF) durante toda a vida e a incidência de câncer (CA) de pulmão no sul do Brasil. Este estudo utilizou o delineamento caso-controle. Tanto casos quanto controles responderam ao questionário contendo questões sobre características sócio-demográficas, sexo, idade e cor da pele, variáveis antropométricas, situação conjugal, escolaridade, tabagismo e histórico familiar de CA. A atividade física foi medida pelo Lifetime Physical Activity Questionnaire. Foram estudados ao todo 249 indivíduos (81 casos e 168 controles). Na análise bruta, a AF de deslocamento aumentou a chance de CA (p=0,01) e as atividades esportivas resultaram em proteção não significativa (p=0,05). Na análise ajustada, a AF ocupacional (p=0,009) e por toda vida (p=0,02) estiveram associadas com menos chance de CA, enquanto que as AF's de deslocamento (p=0,03) e domésticas (p=0,01) estiveram associadas a maior chance de CA. Por essa razão, é de extrema importância o incentivo da prática de AF desde a infância, pois considerando as consistentes evidências da importância da AF na prevenção de inúmeras doenças na idade adulta, incluindo o CA, o seu estímulo em idades precoces pode representar uma estratégia no controle da inatividade física observada em todo o mundo e, consequentemente, reduzir a epidemia das doenças crônicas
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Contrôle de la progression tumorale broncho-pulmonaire par FHIT : Implication du récepteur HER2 / Control of lung tumor progression by FHIT : Involvement of HER2 receptorJouida, Amina 17 March 2017 (has links)
Dans les cancers du poumon, une des altérations les plus souvent observées est la perte ou l’atténuation de l’expression du gène FHIT (Fragile Histidine Triad). Nous avons précédemment montré que FHIT est un suppresseur d’invasion tumorale. En effet, FHIT contrôle l’invasion des cellules tumorales bronchiques en régulant négativement l'expression de gènes associés à la transition épithélio-mésenchymateuse (TEM), en particulier la vimentine et la MMP-9 via l’inhibition d’une voie orchestrée par l’EGFR. Un intérêt particulier a donc été porté aux relations entre FHIT et un autre membre de la famille de l’EGFR : HER2. Nous avons non seulement mis en évidence, in vivo et in vitro, une corrélation inverse entre les taux de FHIT et l’activité du récepteur HER2 dans les CBNPC mais également montré que FHIT est capable de réguler l’activité du récepteur HER2 dans les cellules tumorales pulmonaires et ce grâce à sa dimérisation avec HER3. De plus, l’utilisation de deux inhibiteurs spécifiques d’HER2, le Trastuzumab et l’Irbinitinib, nous a permis de mettre en évidence, que l’activation du récepteur HER2 lors de l’inhibition de FHIT, participe à l’acquisition par les cellules tumorales bronchiques de caractéristiques invasives via la régulation de certaines cibles de la TEM, telles la vimentine, la MMP-14 ou encore le facteur de transcription TWIST-1. Ces résultats montrent que FHIT régule l’activité d’HER2 dans les cellules tumorales pulmonaires et que les inhibiteurs d’HER2 sont capables de limiter l’invasion induite par l’inhibition de FHIT. Cette étude laisse envisager de nouvelles perspectives thérapeutiques pour le cancer du poumon. / The lack or decrease of FHIT (fragile histidine triad) expression is a common event in lung cancer. We recently showed that FHIT acts as a suppressor of tumor invasion. Indeed, FHIT controls the invasive phenotype of lung tumor cells by regulating the expression of genes associated with epithelial-mesenchymal transition (EMT) such as vimentin or MMP-9 through an EGFR signaling pathway. Accordingly, we focused on the relationships between FHIT and another member of this tyrosine kinase receptor family: HER2. First, we observed in vivo and in vitro a negative correlation between FHIT expression and the activated form of HER2 in lung tumor cells. Moreover, FHIT controls HER2 activation through its dimerization with HER3. The use of HER2 specific inhibitors, Trastuzumab and Irbinitinib, allowed to demonstrate that the in vitro invasion induced by FHIT inhibition is HER2-dependent. Furthermore, FHIT controls the HER2-dependent invasion by regulating genes associated with EMT such as vimentin, MMP-14 or TWIST-1. In conclusion, we showed that FHIT regulates HER2 activity in lung tumor cells and that HER2 inhibitors reduce invasion induced by FHIT inhibition. This study would allow for the identification of new therapeutic leads for lung cancer.
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Double-negative (CD27−IgD−) B cells are expanded in NSCLC and inversely correlate with affinity-matured B cell populationsCentuori, Sara M., Gomes, Cecil J., Kim, Samuel S., Putnam, Charles W., Larsen, Brandon T., Garland, Linda L., Mount, David W., Martinez, Jesse D. 15 February 2018 (has links)
Background: The presence of B cells in early stage non-small cell lung cancer (NSCLC) is associated with longer survival, however, the role these cells play in the generation and maintenance of anti-tumor immunity is unclear. B cells differentiate into a variety of subsets with differing characteristics and functions. To date, there is limited information on the specific B cell subsets found within NSCLC. To better understand the composition of the B cell populations found in NSCLC we have begun characterizing B cells in lung tumors and have detected a population of B cells that are CD79A(+)CD27(-)IgD(-). These CD27(-)IgD(-)(double-negative) B cells have previously been characterized as unconventional memory B cells and have been detected in some autoimmune diseases and in the elderly population but have not been detected previously in tumor tissue. Methods: A total of 15 fresh untreated NSCLC tumors and 15 matched adjacent lung control tissues were dissociated and analyzed by intracellular flow cytometry to detect the B cell-related markers CD79A, CD27 and IgD. All CD79A(+) B cells subsets were classified as either naive (CD27(-)IgD(+)), affinity-matured (CD27(+)IgD(-)), early memory/germinal center cells (CD27(+)IgD(+)) or double-negative B cells (CD27(-)IgD(-)). Association of double-negative B cells with clinical data including gender, age, smoking status, tumor diagnosis and pathologic differentiation status were also examined using the logistic regression analysis for age and student's t-test for all other variables. Associations with other B cell subpopulations were examined using Spearman's rank correlation. Results: We observed that double-negative B cells were frequently abundant in lung tumors compared to normal adjacent controls (13 out of 15 cases), and in some cases made up a substantial proportion of the total B cell compartment. The presence of double-negative cells was also found to be inversely related to the presence of affinity-matured B cells within the tumor, Spearman's coefficient of -0.76. Conclusions: This study is the first to observe the presence of CD27(-)IgD(-)double-negative B cells in human NSCLC and that this population is inversely correlated with traditional affinity-matured B cell populations.
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The Role of BRCT-Containing Proteins BRCA1 and PAXIP1 in CancerJhuraney, Ankita 01 January 2015 (has links)
Modular domains of proteins are important in cellular signaling processes. Eukaryotic cells are constantly undergoing DNA damage due to exogenous and endogenous sources of damage. The DNA damage response (DDR) involves a complex network of signaling events mediated by modular domains such as the BRCT (BRCA1 C-terminal) domains. Therefore, proteins containing BRCT domains are important for DNA damage detection and signaling. In this dissertation, we focus on two BRCT-containing proteins BRCA1 and PAXIP1. BRCA1 is a gene that is known to be associated with increased risk of hereditary breast and ovarian cancer. Germline variants of BRCA1 are assessed to determine lifetime risk of developing breast and ovarian cancer. This is performed by genetic testing of the BRCA1 sequence and the variants can be classified as pathogenic, non-pathogenic or variants of unknown significance (VUS). Using family history, segregation analysis, co-occurrence and tumor pathology, certain variants have been classified as either pathogenic or non-pathogenic. However, a large majority of the variants are classified as VUS. Functional assays are critical in providing insight in the case of VUS results. We have a developed a visualization resource to aid in functional analysis of BRCA1 missense variants that occur due to single amino acid changes. This tool is known as BRCA1 Circos (http://research.nhgri.nih.gov/bic/circos/) and it aggregates, harmonizes and allows interpretation of data from all published studies on functional analysis of BRCA1 missense variants. Therefore, this is an important tool that will aid in the meta-analysis of functional data needed to better assess VUS.
Functional studies of BRCA1 also demonstrate that majority of the variants that have a functional impact on the protein lie in the BRCT region of the protein. This indicates that the BRCT region is important in cancer development.
To further analyze the function of BRCT-containing proteins, a study was previously undertaken to evaluate the role of BRCT-containing proteins and their interaction partners in the DNA damage response and consequently, cancer. BRCT domains of seven BRCT-containing proteins were used as baits and their binding partners were demonstrated to be highly enriched in the DDR process. We hypothesized that members of this BRCT-centric protein-protein interaction network could constitute targets for sensitization to DNA damaging chemotherapy agents in lung cancer. Therefore, we probed this established dataset containing the protein-protein interaction network (PPIN) of seven BRCT-containing proteins to identify seventeen kinases. A systematic pharmacological screen was performed to evaluate these kinases as targets to enhance platinum-based chemotherapy in lung cancer and this revealed WEE1, a mitotic kinase, as a potential target. Of the seventeen kinases, inhibition of mitotic kinase, WEE1, was found to have the most effective response in combination with platinum-based compounds in lung cancer cell lines. In the PPIN, WEE1 was shown to interact with PAXIP1 (PTIP), a BRCT-containing protein involved in transcription and in the cellular response to DNA damage. PAXIP1 has been shown to bind DDR proteins, such as 53BP1 and γH2AX, and also shown to be an important part of immune development. In this dissertation, we observe that WEE1 binds to PAXIP1 and PAXIP1 regulates the WEE1-mediated phosphorylation of its main substrate, CDK1. We also demonstrate that ectopic expression of PAXIP1 combined with WEE1 inhibitor, AZD1775, leads to an increase in the mitotic index at the G2/M checkpoint. Overexpression of PAXIP1 combined with AZD1775 treatment in cells with prior DNA damage causes high levels of caspase-3 mediated apoptosis as compared to AZD1775 treatment alone. In summary, we identify the role of PAXIP1 in sensitizing lung cancer cells to the WEE1 inhibitor, AZD1775, in combination with platinum-based therapy and propose the use of WEE1 and PAXIP1 levels as mechanism-based biomarkers. Overall, these studies indicate that BRCT-containing proteins through their role in the DDR and the cell cycle are crucial for both cancer prevention and therapy.
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Lung CT Radiomics: An Overview of Using Images as DataHawkins, Samuel Hunt 04 September 2017 (has links)
Lung cancer is the leading cause of cancer-related death in the United States and worldwide. Early detection of lung cancer can help improve patient outcomes, and survival prediction can inform plans of treatment. By extracting quantitative features from computed tomography scans of lung cancer, predictive models can be built that can achieve both early detection and survival prediction. To build these predictive models, first a detected lung nodule is segmented, then image features are extracted, and finally a model can be built utilizing image features to make predictions. These predictions can help radiologists improve cancer care.
Building predictive models based on medical images is the basis of the budding field of radiomics. The hypothesis is that images contain phenotypic information that can be extracted to aid prediction and that automated methods can detect some things beyond human detection. With improved detection and predictive models radiomics aims to help assist radiologists and oncologists provide personalized care.
In this work a model is presented to predict long term survival versus short term survival. Forty adenocarcinoma diagnostic lung computed tomography (CT) scans from Moffitt Cancer Center were analyzed for survival prediction. These forty cases were in the top and bottom quartile for survival. A decision tree classifier was able to predict the survival group with an accuracy of 77.5% using five image features chosen from 219 using relief-f.
Another contribution of this work is a model for predicting cancer from suspicious nodules. The national lung screening trial was used to build a training set of 261 screening CTs and a test set of 237 CTs. These images were taken at the initial screening, one and two years before cancer developed. From these precursor images, which nodules developed into cancer, could be predicted at 76.79% accuracy with an area under the receiver operating characteristic curve of 0.82. A risk score was also developed to provide a measure of risk during screening. The developed risk score performed favorably in predictive accuracy compared to Lung-RADS on this data set.
The Data Science Bowl was also entered and this work examines the knowledge gained from a large-scale competition to improve imaging. In this competition participants were tasked with predicting cancer from 1397 training cases on 506 test cases. The winning entry performed with a logLoss of 0.39975 while making use of all the training data while our entry scored 1.56555 with a different set of training data. A lower logLoss shows greater accuracy. This work explains our approach and examines the winning entry.
An overview of the state of radiomicis as it applies to lung cancer is also provided. These contributions of predictive models will help to provide decision support to medical practitioners. By providing tools to the medical field the goal is to advance automated medical imaging to aid clinicians in creating diagnosis and treatment plans.
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Barriers to the Access of Bevacizumab in Patients with Solid Tumors and the Potential Impact of Biosimilars: A Physician SurveyMonk, Bradley, Lammers, Philip, Cartwright, Thomas, Jacobs, Ira 28 January 2017 (has links)
Access to bevacizumab, an important component of oncology treatment regimens, may be limited. This survey of oncologists in the US (n = 150), Europe (n = 230), and emerging markets (EM: Brazil, Mexico, and Turkey; n = 130) examined use of and barriers to accessing bevacizumab as treatment of advanced solid tumors. We also assessed the likelihood that physicians would prescribe a bevacizumab biosimilar, if available. Bevacizumab was frequently used as early-line therapy in metastatic colorectal cancer, metastatic non-squamous non-small-cell lung cancer, and metastatic ovarian cancer (all markets), and as a second-line therapy in glioblastoma multiforme (US, EM). A greater percentage of EM-based physicians cited access-related issues as a barrier to prescribing bevacizumab versus US and EU physicians. Lack of reimbursement and high out-of-pocket costs were cited as predominant barriers to prescribing and common reasons for reducing the number of planned cycles. Overall, similar to 50% of physicians reported they "definitely" or "probably" would prescribe a bevacizumab biosimilar, if available. Efficacy and safety data in specific tumor types and lower cost were factors cited that would increase likelihood to prescribe a bevacizumab biosimilar. A lower cost bevacizumab biosimilar could address the unmet needs of patients and physicians worldwide, and may have the greatest impact on patient outcomes in EM.
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