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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.
31

Assessment of the modulation of photodynamic effect by β-glucan and characteristics of anti-CD7 monoclonal antibody during tumor process / Fotodinaminio poveikio moduliacijos β-gliukanu vertinimas ir monokloninio antikūno prieš CD7 savybių tyrimas navikinio proceso metu

Akramienė, Dalia 09 March 2011 (has links)
Activation of the immune system during photodynamic therapy (PDT) and improvement of the effector functions of mAbs - these are the ways to use and enhance the potential of the immune system to fight cancer. Tumor cells lack β-glucan as a surface compo¬nent and can‘t trigger complement receptor 3-dependent cellular cytoto¬xicity and initiate tumor-killing activity during PDT. So, it gave rise to the hypothesis that β-glucan in combination with PDT will produce more effective killing of by iC3b fragment opsonized tumor cells. The human Fc portion is essential for the recruiting of human effector immune cells to produce antitumor effect. Therefore, connection of Fv portion of murine anti-CD7 antibody with Fc portion of human IgG1 can be helpful for such protein to obtain ideal feathers. However, each modification of the monoclonal antibody can cause the lost or decrease in the rate of protein expression and antigen-binding properties. Monoclonal antibody products are unique in their molecules. Because of post-translational modifications that often occur during the fermentation process, the final product is heterogeneous. Therefore, careful characterization of monoclonal antibodies is required in order to assess their identity, purity, potency and safety. Response of Lewis lung carcinoma tumor to PDT modulated by β-glucan was assessed in mice and functional characteristics of novel purified chimeric anti-CD7 antibody was tested in this study. / Imuninės sistemos aktyvinimas taikant fotosensibilizacinę terapiją (FNT) ir monokloninių antikūnų efektorinių funkcijų gerinimas yra vienas iš būdų, kaip naudoti ir sustiprinti organizmo imuninės sistemos veiksnių potencialą kovai su naviku. Navikinės ląstelės membranos paviršiuje nėra β-gliukano, todėl FNT metu negali būti aktyvinamas nuo komplemento receptoriaus 3 priklausomas ląstelės citotoksiškumo mechanizmas bei sukeliama navikinės ląstelės žūtis. Todėl galima tikėtis, kad β-gliukanas ir FNT, taikomi kartu, gali aktyvinti iC3b frag¬mento opsonizuotų navikinių ląstelių žūtį. Norint aktyvinti žmogaus imunines ląsteles priešnavikiniam poveikiui sukelti, pelės monokloniniam antikūnui būtina žmogaus imunoglobulino Fc dalis. Todėl pelės antikūno prieš CD7 vienos grandinės Fv fragmento sujungimas su žmogaus imunoglobulino G1 Fc dalimi baltymui gali suteikti idealias savybes. Tačiau, bet kokia monokloninio antikūno modifikacija gali keisti jo savybes ir, išskiriant baltymą, dėl daugiapakopio proceso ji gali keistis. Todėl, norint įvertinti chimerinio CD7-Fc antikūno identiškumą, grynumą, veiksmingumą bei saugumą, būtina atlikti tyrimus, kuriais būtų galima nustatyti, ar antikūnas išlaiko specifiškumą antigenui, kaip aktyviai jungiasi prie jo, ar aktyvina imuninius mechanizmus. Šio tyrimo metu buvo vertintas pelėms įskiepytos Luiso plaučių karcinomos atsakas į FNT moduliaciją β-gliukanu ir išgrynintas chimerinis antikūnas prieš CD7 bei ištirtos jo funkcinės savybės in vitro.
32

Análise e comparação da expressão imunoistoquímica de marcadores moleculares (ERCC1, Bcl-2, Lin28a e Ki67) potencialmente preditores de resposta à quimioterapia em carcinomas neuroendócrinos extra-pulmonares e carcinoma de pequenas células de pulmão / Evaluation of biomarkers (ERCC1, BCL-2, Lin28a e Ki67) potencially predictive of response and prognosis in patients with high-grade extrapulmonary neuroendocrine carcinomas or small cell lung cancer treated with platin-based chemotherapy

Juliana Florinda de Mendonça Rêgo 21 November 2016 (has links)
INTRODUÇÃO: O carcinoma de pulmão de pequenas células (CPPC) e o carcinoma neuroendócrino (CNE) extra-pulmonar apresentam características histopatológicas e tratamentos similares, porém os desfechos encontrados nos dois grupos podem ser diferentes. Avaliamos a expressão de alguns biomarcadores e a associação destes com taxa de resposta (TR) à quimioterapia baseada em platina e sobrevida global (SG) nos dois grupos. METODOS: Realizamos estudo retrospectivo de pacientes com CPPC e CNE extra-pulmonares tratados com quimioterapia baseada em platina. Todas as amostras tumorais foram revisadas pelo mesmo patologista (R.S.S.M.) e analisadas quanto a expressão imunoistoquímica de Ki-67, ERCC1, Bcl-2 e Lin28a, a qual foi determinada através do H-escore (calculado multiplicando o produto da intensidade da coloração - 0 a 3 - com a porcentagem de células positivas - 0 a 100 -, podendo variar de 0 a 300 - positivo quando >= 200). Os biomarcadores foram analisados tanto como variáveis contínuas quanto categóricas e a TR foi determinada por RECIST 1.1. A associação entre a expressão de cada biomarcador e a TR foi avaliada através do teste de qui-quadrado ou teste exato de Fisher para variáveis categóricas e regressão logística simples para variáveis contínuas. Sobrevida global foi estimada por Kaplan-Meier e as curvas foram comparadas por log-rank. O modelo de regressão de cox foi utilizado para avaliar associação entre SG e a expressão de biomarcadores como variável contínua. RESULTADOS: Entre Julho de 2006 e Julho de 2014, 142 pacientes foram identificados: N=82 (57,7%) com CPPC e N=60 (42,3%) com CNE extra-pulmonar. As características clínicas eram semelhantes em ambos os grupos. Mediana de ki67 foi de 60% (7-100) no CPPC e de 50% (20-95%) no segundo grupo (p=0,858). Com uma mediana de 5 ciclos por paciente (N=123 elegíveis para análise de TR), a TR foi de 86,8% no CPPC, enquanto nos com CNE extra-pulmonar, foi de 44,6% (p < 0.001). A mediana de SG (N=132 elegíveis para análise da SG) foi similar entre os grupos (10,3 meses em CPPC e 11,1 meses em CNE extra-pulmonar; p=0,069). Não houve diferença no padrão de expressão do ERCC1 (p=0,277) e do Lin28a (p=0,051) entre os grupos. Bcl2 foi expresso em 38 pacientes (46,3%) com CPPC e em 17 pacientes (28,3%) com CNE extra-pulmonar (p=0,030). Apenas no grupo com CNE extra-pulmonar, a alta expressão do Bcl2 foi associada com pior prognóstico (8,0 meses vs 14,7 meses; p=0,025). A expressão dos demais marcadores em CNE extra-pulmonar e dos quatro em CPPC não apresentou influência sobre a SG, não havendo também associação entre estes e a taxa de resposta à quimioterapia. Dentre os pacientes com CNE extra-pulmonar, não houve diferença na SG ou na TR entre os pacientes com carcinoma bem diferenciado (N=13;) e com carcinoma pouco diferenciado (N=47). CONCLUSÃO: Apesar do CPPC e do CNE extra-pulmonar serem tratados de forma semelhante, nesta coorte a taxa de resposta entre os grupos foi significativamente diferente. Quando comparado com CPPC, os pacientes com CNE extra-pulmonar apresentam uma menor responsividade à quimioterapia baseada em platina, mas com tendência a maior SG. Dentre os CNE extra-pulmonares, a alta expressão de Bcl-2 foi associada a pior prognóstico. Os demais biomarcadores não apresentaram papel preditor de resposta ou prognóstico / INTRODUCTION: Small cell lung cancer (SCLC) and high-grade extrapulmonary neuroendocrine carcinomas (EPNEC) share similar histopathological features and treatment, but outcomes may differ. We evaluated the expression of biomarkers and their association with response rate (RR) to platin-based chemotherapy and overall survival (OS) in these entities. METHODS: We conducted a retrospective analysis of patients with advanced EPNEC and SCLC treated with platinum-based chemotherapy. A single pathologist (R.S.S.M.) revised all samples. Paraffin-embedded tumor samples were tested for Ki-67, ERCC1, Bcl-2 and Lin28a expression by immunohistochemistry (IHC). Final IHC score (H-score) was calculated multiplying the intensity of staining by grading (0-300, with >= 200 considered positive). Biomarkers were analyzed as both categorical and continuous variables. RR was determined by RECIST 1.1. Associations between each biomarkers expression and RR were assessed using Chi-square or Fisher\'s exact test for categorical variables and univariate logistic regression for continuous variables. OS was estimated by the Kaplan-Meier method and curves were compared by log-rank. Cox regression analysis was used to evaluate any association between biomarkers expression (continuous variables) and OS. RESULTS: From July 2006 to July 2014, 142 patients were identified: N=82 (57,7%) with SCLC and N=60 (42,3%) with EPNEC. Baseline clinical characteristics were similar. Median Ki67 was 60% (7-100) among SCLC patients and 50% (20-95%) in EPNEC (p=0,858). With a median of 5 cycles per patient in both groups (N=123 evaluable patients), the RR was significantly higher in the SCLC group (86,8% vs 44.6%; p < 0.001). Median OS (N=132 evaluable patients) was similar between the groups (10.3 months in SCLC and 11.1 months in EPNEC; p=0,069). In the EPNEC group, there wasn\'t any difference in OS or RR between the patients with welldifferentiated (N=13) and poorly differentiated carcinoma (N=47). ERCC1 (p=0.277) and Lin28a (p=0.051) were similarly expressed between the groups. Bcl2 was expressed in 38 SCLC patients (46.3%) and in 17 EPNEC patients (28.3%; p=0.030). Only in the EPNEC group, Bcl2 high expression was associated with worse survival (8.0 months vs 14.7 months; p = 0.025). RR to chemotherapy was not influenced by the expression of the ERCC1, Lin28a, Bcl-2, Ki-67 in either EPNEC or SCLC groups. CONCLUSION: Even though SCLC and EPNEC are treated similarly, in this cohort, the rate response differed significantly. When compared with SCLC, patients with EPNEC apparently had tumors less responsive to platin-based chemotherapy, but tended to live longer. In EPNEC treated with platin, high expression of Bcl2 was associated with poor prognosis. We could not identify additional predictive or prognostic biomarkers
33

Optimalizace metodiky pro stanovení volné nádorové DNA v plazmě a její klinické využití u pacientů s karcinomy kolorekta, plic a slinivky břišní / Optimization of proces for detection of free tumor DNA in plasma and its clinical utility for colorectal cancer, lung cancer and pancreatic cancer patients

Belšánová, Barbora January 2017 (has links)
In current days, examination of circulating tumor DNA (ctDNA) finds new use across different cancers. It is directed at tumor-derived short fragments of DNA present in peripheral blood of patiens (mainly in advanced stages). Due to its minimal invasivity, almost 100 % specificity and relatively high sensitivity in stage IV patients, this approch found its main potential clinical utility especially in early detection of disease relapse or progression after tumor resection (i.e. post-operative follow-up), prediction and monitoring of therapy response and estimation of prognosis. As a result of minute levels of ctDNA on a high background of other non-tumor DNA fragments present in plasma, a suitable method exhibiting highest sensitivity is the key for proper detection of this marker. The approach is predominantly based on initial identification of a mutation in tumor tissue and its subsequent detection in plasma. The present work is aimed at optimization of ctDNA isolation and method of its detection based on PCR amplification followed by heteroduplex analysis by denaturing capillary electrophoresis (DCE) to achieve highest sensitivity for detection of mutated fraction in plasma sample. I have applied the optimized protocol to examine ctDNA in three types of cancers, namely colorectal cancer (122...
34

Influence des caractéristiques morphologiques et mutationnelles des carcinomes pulmonaires sur leur environnement immunitaire et leur pronostic / Impact of mutational and morphological characteristics of non small cell lung carcinoma on immune environment and prognosis

Mansuet-Lupo, Audrey 04 July 2014 (has links)
Il est maintenant bien établi que le système immunitaire joue un rôle majeur dans le contrôle des tumeurs, y compris dans les carcinomes pulmonaires. Cependant, les interactions entre les cellules tumorales et les cellules immunitaires du microenvironnement tumoral sont mal connues. Dans ce travail, nous avons étudié les caractéristiques morphologiques et moléculaires des cellules tumorales provenant d’adénocarcinomes pulmonaires et leur association avec la composition du microenvironnement immunitaire. Nous avons rapporté la valeur pronostique des paramètres morphologiques de ces tumeurs, comme le grade histologique des adénocarcinomes, et leur association avec le statut moléculaire EGFR et KRAS. Nous avons émis l’hypothèse que la diversité morphologique et moléculaire de ces tumeurs pouvait être associée à une signature immunitaire intra-tumorale spécifique et que cela pourrait avoir un impact pronostique. Nous avons mis en évidence que la densité des cellules dendritiques matures, situées au sein de structures lymphoïdes tertiaires, variait en fonction du statut moléculaire EGFR et KRAS des tumeurs. De même, l’impact pronostique des cellules dendritiques matures et des lymphocytes CD8+ variait en fonction du statut moléculaire des tumeurs. Nous avons également retrouvé la valeur pronostique de l’environnement immunitaire, représenté par la densité en cellules dendritiques matures et en lymphocytes CD8+, sur la survie à long terme des carcinomes pulmonaires de stade III-N2 opérés après chimiothérapie néoadjuvante. Enfin, nous avons démontré que la chimiothérapie n'est pas associée à de profondes modifications de l’infiltrat immunitaire, alors qu’elle entraîne des modifications des cellules tumorales. L’ensemble de ces résultats suggère que l’infiltrat immunitaire est intimement lié à la cellule tumorale et que la composition du microenvironnement immunitaire varie avec les caractéristiques de la tumeur. Cette interaction entre les cellules tumorales et les cellules immunitaires contribue au pronostic de ces tumeurs. Ces données démontrent l’intérêt d’utiliser des traitements combinant des drogues cytotoxiques, telle la chimiothérapie conventionnelle, à des traitements immunomodulateurs permettant de favoriser une réponse immunitaire anti-tumorale efficace. / The major role of the immune system against tumor development is now clearly established, including lung carcinoma. Nevertheless, interaction between tumoral cells and immune environment is less well-defined. In that study, we have studied morphological and molecular tumoral cells characteristics from lung adenocarcinoma and their role in the composition of immune environment. We reported the prognostic value of morphological parameters, as histological grade of adenocarcinoma, and their association with molecular EGFR and KRAS status. We hypothesized that morphological and molecular diversity of these tumors could be associated with a specific intratumoral immune signature, and could have an impact in prognosis. We showed that mature dendritic cells density, located in tertiary lymphoid structures, differed according to EGFR and KRAS status. Morever, molecular status of tumors modified the pronostic value of mature dendritics cells and CD8+ T cells. We found a prognostic value of immune environment, represented by dendritic cells and T CD8+ cells, in operated stage III-N2 lung carcinomas treated by neoadjuvant chemotherapy. At last, we demonstrated that chemotherapy is not associated with wide modifications in immune infiltrate, whereas it induced modifications in tumoral cells. All together, these data strongly argue for a close link between tumoral cells and immune environment, which seems to depend on tumoral cell characteristics. This interaction between tumoral cells and immune cells contribute to the prognosis of these tumors. These results show the evidence that combine cytotoxic treatment, like conventional chemotherapy, with immunomodulators, favour a protective anti-tumor immune response.

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