Orientador: Leonilda Maria Barbosa dos Santos / Dissertação (Mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T19:55:43Z (GMT). No. of bitstreams: 1 Paula_RosemeireFlorencadeOliveirade_M.pdf: 1324085 bytes, checksum: 46d777e0734d49f399f5275c0ef511c3 (MD5) Previous issue date: 2012 / Resumo: A capacidade dos nanotubos de carbono penetrar nas células abriu a possibilidade da utilização dessas nanopartículas no diagnóstico e tratamento das neoplasias malignas. Contudo, pouco se conhece sobre o efeito dessas partículas não funcionalizadas, ou seja, sem moléculas acopladas, sobre a resposta imune. Nesse estudo demonstramos que nanotubos de carbono de paredes múltiplas (MWCNT) corados com substância fluorescente penetram nas células de carcinoma de pulmão (LLC) de camundongos. A internalização dessas partículas foi avaliada utilizando-se microscopia confocal e citometria de fluxo. Uma vez dentro das células o MWCNT inibiu a resposta proliferativa das LLC in vitro. A inoculação dos nanotubos de carbono in vivo também reduziu a velocidade de crescimento do tumor. A redução da velocidade de crescimento foi acompanhada de aumento da resposta proliferativa dos linfócitos estimulados por mitógeno inespecífico e pela expressão de IFN. O IFN está envolvido na resposta contra os tumores e esses resultados indicam que os nanotubos de carbono estimulam a resposta imune. Por outro lado, verificou-se significativa redução da expressão citocinas como TNF, IL-17, IL-10 e TFG, que estão envolvidas na resposta imunes pró-tumor. Esses resultados indicam que, mesmo na ausência de funcionalização, os nanotubos de carbono ativam a resposta imune e que conseqüentemente a resposta imune altera o crescimento desse tumor / Abstract: The ability of carbon nanotube to penetrate cells opens the possibility for using these particles on diagnosis and treatment of malignant neoplasms. However, little is known about the effect of the non functionalized carbon nanotube, in other words, without attached molecules, on the immune response. In this study, we demonstrate that the multi-walled carbon nanotubos (MWCNT) stained with a fluorescent dye can penetrate mouse lung carcinoma (LLC) cells. These particles internalization was evaluated by confocal microscopy and flow cytometry. Once inside the cells, the MWCNT inhibited the LLC proliferative response in vitro. The in vivo inoculation of MWCNT in tumor-bearing mice also resulted in the reduction of tumor growth. The growth speed reduction was accompanied by mitogen nonspecific stimulation of T lymphocyte proliferative response and IFN expression. The IFN is involved on response against tumor and these results show that the carbon nanotubes stimulate the immune response. On the other hand, a significant reduction on cytokines like TNF, IL-17, IL-10 e TFG that are involved on pro- tumoral immune response was verified. These results show that, even without functionalization, the carbon nanotubos activate the immune response and consequently the immune response changes the tumoral growth / Mestrado / Clinica Medica / Mestra em Clínica Médica

Introdução: O câncer de pulmão está entre os principais tipos de neoplasias, sendo o adenocarcinoma o tipo histológico mais frequente. Atualmente, tem-se buscado marcadores de prognóstico para o carcinoma não de pequenas células. Objetivo: analisar os níveis da cinase reguladora extracelular (ERK) ativada em amostras histológicas de pacientes em estágios iniciais de adenocarcinoma de pulmão que foram submetidos a tratamento cirúrgico e suas correlações com dados clínicos e sobrevida. Material e métodos: foram selecionados aleatoriamente 36 pacientes com adenocarcinoma de pulmão nos estágios I e II submetidos a lobectomia pulmonar entre 1998 e 2004. Os pacientes foram divididos em dois grupos segundo os achados imuno-histoquímicos: pacientes com menos de 15% da positividade de células tumorais para ERK e pacientes com 15% ou mais de células positivas. Para comparação com os achados foi realizada análise de enriquecimento de base de dados de microarranjos (GSE29016, n = 72). Resultados: 21 pacientes (58%) apresentaram níveis da ERK ativada acima de 15% e 15 pacientes (43%) abaixo de 15%. Não foram observadas diferenças estatisticamente significativas para idade, sexo, tabagismo e índice de massa corporal entre os grupos estratificados para a ERK. O grupo de maior positividade (≥15%) apresentou menor sobrevida (P = 0,045). As análises de enriquecimento não demonstraram correlação da variação da expressão gênica de ERK em pacientes com adenocarcinoma quando comparados com a sobrevida nos estágios I e o grupamento dos estágios II e III. Conclusões: a alta positividade da ERK em células de amostras biológicas de pacientes com adenocarcinoma de pulmão está relacionada a tumores mais agressivos e com pior prognóstico. / Introduction: Lung cancer is among the most common types of neoplasias, and adenocarcinoma is the most frequent histological type. Currently, there is an extensive search for prognostic biomarkers of squamous nonsmall cell lung cancer. Objective: To analyze the correlation of clinical data and patient survival with the levels of activated extracellular regulatory kinase (ERK) in histological samples of surgically resected early stage lung adenocarcinoma. Methods: We randomly selected 36 patients with stage I or II lung adenocarcinoma who underwent pulmonary lobectomy between 1998 and 2004. Patients were divided into the following 2 groups according to immunohistochemical profile: a group with <15% ERK-positive tumor cells and a group with ≥15% ERK-positive tumor cells. For data comparison, an enrichment analysis of a microarray database was performed (GSE29016, n = 72). Results: Activated ERK levels were ≥15% and <15% in 21 (58%) and 15 (43%) patients, respectively. There were no statistically significant differences in age, sex, smoking history, and body mass index among the groups stratified by ERK levels. The survival rate was lower in the ERK ≥15% group than in the ERK <15% group (P = 0.045). Enrichment analyses showed no correlation between variations in gene expression of ERK in adenocarcinoma patients and survival rates in patients with stage I and combined stage II+III disease. Conclusions: High ERK positivity in cells from biological samples of lung adenocarcinoma is related with tumor aggressiveness and a poorer prognosis.

Orientadores: Liliana Aparecida Lucci De Angelo Andrade, Sophie Francoise Mauricette Derchain / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T12:06:20Z (GMT). No. of bitstreams: 1 Pinto_PaolaBertolottiCardoso_D.pdf: 22982855 bytes, checksum: ca4a4e679f0037c1494bf2866a333968 (MD5) Previous issue date: 2013 / Resumo: Os carcinomas mucinosos do ovário são raros e representam apenas 3% dos carcinomas. Frente a este diagnóstico, é preciso descartar a possibilidade de metástase para o ovário, principalmente de neoplasia primária do trato gastrointestinal. Apesar da avaliação morfológica, macro e microscópica, e das reações imunoistoquímicas contribuírem para o diagnóstico diferencial, existem casos de difícil diferenciação. Um algoritmo para separar os carcinomas mucinosos primários dos metastáticos no ovário foi proposto na literatura e determina que são metastáticos os tumores bilaterais ou unilaterais menores que 13cm, classificando as neoplasias com uma acurácia de quase 90%. Objetivos: comparar os aspectos macro e microscópicos aliados à avaliação imunoistoquímica para a diferenciação entre tumores mucinosos primários e metastáticos no ovário, avaliando a acurácia do algoritmo nos casos, os dados clínicos e sua evolução. Métodos: Todos os tumores mucinosos envolvendo o ovário, dos arquivos do Laboratório de Anatomia Patológica da UNICAMP no período de 1994 a 2009 foram levantados. Feita revisão dos prontuários com descrição dos dados clínicos, evolução das pacientes, revisão de lâminas para avaliação de dados histopatológicos e seleção dos blocos de parafina para a construção de micro-arranjo de tecidos, onde foram realizadas as reações imunoistoquímicas para: CK7, CK20, ?-catenina, WT-1, CDX-2, Dpc-4, CA125, RE e RP. Resultados: Dos 76 casos selecionados, 35 eram carcinomas mucinosos primários do ovário, 33 eram metastáticos e em 8 casos o primário não foi definido, sendo excluídos da análise estatística. A sobrevida média foi maior nos primários (65X35 meses; p<0.0001). A acurácia do algoritmo foi de 82,1%. A maioria dos metastáticos originou-se do cólon ou reto (54%). Dos primários, 85% eram unilaterais >13 cm e dos metastáticos, 61% eram bilaterais e 18% unilaterais <13cm. Entre as características histológicas, êmbolos carcinomatosos e a ausência de gradiente morfológico foram mais observados nos metastáticos. Na análise bivariada dos marcadores apenas CK7, CK20 e CDX2 mostraram diferenças significantes entre os grupos, entretanto houve muita sobreposição de resultados. Após análise multivariada foram selecionados: gradiente histológico e CK7 para formação de um novo algoritmo que definiu, com acurácia de 91%, que um tumor é metastático quando apresenta qualquer um dos aspectos: bilateral; unilateral e <13 cm; ausência de gradiente histológico; ou gradiente histológico presente com falta de expressão do CK7. Conclusão: tanto o algoritmo, como as reações imunoistoquímicas e os aspectos morfológicos são úteis no diagnóstico diferencial entre primário e metastático, porém não há nenhum dado discriminatório e, em alguns casos, somente a análise com equipe multidisciplinar pode definir o primário, reconhecendo as peculiaridades deste diagnóstico desafiador / Abstract: Primary ovarian mucinous carcinomas are uncommon and the most important differential is metastatic adenocarcinoma, mainly from gastrointestinal origin. Besides immunohistochemical profile, an algorithm determines, with a high accuracy, that unilateral and >13cm tumors are primary carcinomas and all the others, metastasis. Objective: to describe clinical and histopathological aspects of mucinous carcinomas, assessing the algorithm accuracy and immunohistochemical markers contributory to diagnosis. Methods: 76 mucinous carcinomas from our files (1994-2009) were revised; immunohistochemical reactions for CK7, CK20, Ca125, hormonal receptors (ER, PR), WT1, SMAD4, ?-catenin, CDX2 were performed by TMA. Results: 35 were ovarian primary tumors (group 1), 33 were metastasis (group 2). In eight cases the primary was not identified and these were excluded from statistic analysis. Most of the metastasis were from colorectal cancer (54%). Mean survival differed between the groups (65X35 months; p<0.0001). Agreement with the algorithm was 82.1%. In group 1, 85% were unilateral >13cm; in group 2, 61% were bilateral and 18% unilateral tumors <13cm. Different from group 1, common features in group 2 were vascular invasion and tumors without histological gradient. Bivariate analysis pointed out CK7, CK20 and CDX2 as main markers to distinguish both groups, but overlapping of the results was observed. After multivariate analysis, 2 aspects were selected: histological gradient and CK7; a new algorithm was designed and established with an accuracy of 91%, that a mucinous carcinoma is metastatic to the ovary when it shows one of the aspects: bilateral, or unilateral and <13cm, or without histological gradient, or presence of histological gradient but CK7 is negative. Conclusion: Algorithm and immunohistochemistry are useful, but there is no gold-standard marker. In some cases, only multidisciplinary evaluation can achieve reliable anatomo-clinical diagnosis, in this challenging situation / Doutorado / Anatomia Patologica / Doutora em Ciências Médicas

Orientador: Nelson Adami Andreollo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T20:48:16Z (GMT). No. of bitstreams: 1 CoelhoNeto_JoaodeSouza_D.pdf: 3555108 bytes, checksum: 8ec52e1b0f88869350f9b5b3aad97a23 (MD5) Previous issue date: 2015 / Resumo: A esofagogastrectomia total seguida de esofagocoloplastia é um procedimento cirúrgico complexo com alta morbimortalidade. Suas indicações são limitadas a algumas condições, principalmente nas ressecções radicais de grandes tumores da transição esôfago-gástrica que invadem ambas as vísceras e tumores esofágicos em pacientes com gastrectomias prévias. Objetivo: Analisar as indicações e os resultados das esofagogastrectomias totais seguidas de esofagocoloplastias nas neoplasias do esôfago distal e da transição esôfago-gástrica realizadas no Hospital de Clínicas da Faculdade de Ciências Médicas da UNICAMP no período de 1989 a 2013. Métodos: Estudo descritivo longitudinal retrospectivo, com os indivíduos submetidos à esofagogastrectomia total seguida de esofagocoloplastia. As variáveis foram obtidas da revisão retrospectiva dos prontuários médicos. Para a análise de sobrevida foi utilizado o método de estimação de Kaplan-Meier. Para as comparações das distribuições de sobrevida foi utilizado o teste de Wilcoxon (Breslow) ou Log Rank. Casuística: Vinte pacientes foram submetidos a esofagogastrectomia total seguida de esofagocoloplastia no Hospital de Clínicas da UNICAMP. Resultados: Em todos os casos, a técnica cirúrgica empregada consistiu em laparotomia mediana e cervicotomia lateral esquerda, sendo a esofagectomia realizada por via transhiatal, associado a linfadenectomia D2. Nas reconstruções foram realizadas nove esofagocoloduodenoplastias e as 11 demais foram esofagocolojejunoplastias em Y de Roux. A via de transposição preferencial foi a transmediastinal (65%). Três casos eram estadios I/II (15%), 15 (85%) eram estadios III/IV, refletindo o diagnóstico tardio destes tumores. A mortalidade peri-operatória foi de cinco pacientes (25%): uma mediastinite secundária à necrose do cólon transposto (5%), uma celulite abdominal secundária a infecção de ferida operatória, uma broncopneumonia grave, um choque irreversível e uma sepse associada a fístula da anastomose colo-jejunal. Não houve óbito no intra-operatório. Quatro pacientes faleceram no primeiro ano de pós-operatório, sendo três (15%) deveram-se a recidiva tumoral e um (5%) secundário a broncopneumonia. A sobrevida global estimada foi de 52,4% em um ano, de 30,6% em três anos e de 22,9% em cinco anos. A sobrevida mediana foi de 12,7 meses. Conclusão: A esofagogastrectomia total associada à esofagocoloplastia é procedimento de elevada morbimortalidade, portanto necessitando indicação precisa. Evidentemente, pacientes corretamente selecionados beneficiam-se da cirurgia. É um procedimento que visa o aumento da sobrevida e a melhora da qualidade de vida / Abstract: Introduction: Total esophagogastrectomy with colon interposition for esophageal replacement is a complex surgical procedure and has high morbidity and mortality ratios. Indications for surgery are limited to some condition when it is necessary to resect both viscera stomach and esophagus or when de stomach is not available due to previous gastrectomy. Objectives: Analyze the indications and the outcomes of total esophagogastrectomy in neoplasms of esophagus and esofagogastric junction performed in State University of Campinas's Hospital between 1989 and 2013. Methods: It is a longitudinal retrospective descriptive study. Medical records were reviewed to obtain data about pre and postoperative treatment. For descriptive analysis and estimation of the survival model it was used Kaplan-Meier curve and Wilcoxon (Breslow) or Log Rank tests. Casuistic: From 1989 to 2013, 20 patients underwent total esophagogastrectomy followed by esophagocoloplasty in the University Hospital Results: In all cases, were performed left neck incision, transhiatal esophagectomy associated to D2 lymphadenectomy. Reconstructions were performed in 9 cases by esophacoloduodenoplasty and esophagocolojejunoplasty in 11 cases (after 2004) in order to avoid alkaline reflux. The colon interposition grafts were performed thru the mediastinum in 65% of the patients. Three cases were stages I / II (15%), while 17 (85%) cases were stages III / IV, reflecting the delayed diagnosis of these tumors. The operative mortality occurred in five patients (25%): one mediastinitis secondary to necrosis of the transposed colon, one cellulites secondary to abdominal wound infection, one severe bronchopneumonia, one severe shock in the immediate post operatory day and one sepsis associated with abdominal colojejunostomy anastomotic leak. Four patients died in the first year after surgery, being three due to tumor recurrence (15%) and one secondary to bronchopneumonia (5%). The estimated overall survival was 52.4% in one year, 30.6% in three years and 22.9% in five years. The median survival was 12.7 months. Conclusion: The total esophagogastrectomy associated to esophagocoloplasty presented high morbidity and mortality, thus requiring precise indication, and of course, properly selected patients benefit greatly from surgery, with the risk-benefit ratio acceptable, improving their quality of life and survival / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências

Background: New prognostic grade groupings were recently proposed for prostate cancer. They are based on Gleason grading of either biopsy or prostatectomy specimen. Former Gleason 6 corresponds to group 1, Gleason 7=3+4 corresponds to group 2, Gleason 7=4+3 corresponds to group 3, Gleason 8 corresponds to group 4, and Gleason 9-10 correspond to group 5. Objective: To assess the prognostic value of Gleason grade groups in men with prostate cancer from a nationwide population‑based cohort. Design, Setting and Participants: From the National Prostate Cancer Register of Sweden, we identified 5,880 men diagnosed with prostate cancer from 2005 to 2007, including 4,325 who had radical prostatectomy and 1,555 treated by radiotherapy.  Outcome Measurements and Statistical Analysis: Kaplan-Meier survival analysis was used to calculate the cumulative 4-year biochemical recurrence-free survival. Cox proportional hazards regression models were used to examine the relationship between prognostic Gleason grade groups and biochemical recurrence after radical prostatectomy and radiotherapy. The 4-year biochemical progression-free survival was compared for groups based on biopsy and prostatectomy Gleason grade groups. Results and Limitations: Among men undergoing surgery, the 4‑year biochemical progression-free survival was 89%, 82%, 74%, 77%, and 49% for prognostic Gleason grade groups 1-5 on biopsy. The corresponding 4-year biochemical progression-free survival based on prostatectomy prognostic Gleason grade groups was 92%, 85%, 73%, 63%, and 51% for prognostic Gleason grade groups 1-5. For men undergoing radiotherapy, biopsy prognostic Gleason grade groups 1-5 had 4-year biochemical progression-free survival of 95%, 91%, 85%, 78%, and 70%. After adjusting for preoperative serum prostate specific antigen and clinical stage, biopsy prognostic Gleason grade groups were significant independent predictors of biochemical progression after radical prostatectomy and radiotherapy. There was no central review of pathology. Conclusions: These results confirm the prognostic value of the newly proposed prognostic Gleason grade groups in men undergoing radical prostatectomy and radiotherapy in a population-based setting.

Oesophageal adenocarcinoma (OAC) is a leading cause of cancer death in the UK and current systemic therapies are ineffective for the majority of patients. The central aim of this work was to explore strategies to identify novel therapeutic targets. Research has failed, thus far, to identify a dominant oncogene in OAC, although the tumour suppressor p53 is frequently mutated. Inhibiting the mitotic kinase, polo-like kinase 1 (PLK-1), was proposed as a synthetic lethal strategy. PLK-1 was demonstrated to be over-expressed in both verified OAC cell lines and human OAC tissue compared to non-transformed cells and epithelium. Mutation of p53 was associated with over-expression of PLK-1 in both OAC and ovarian cancer tissue. Using a carefully validated viability assay, both an established and novel PLK-1 inhibitor were demonstrated to induce a G2/M arrest and reduce OAC cell proliferation. Relative selectivity was demonstrated for OAC compared to non-transformed cells. This therapeutic window could be enhanced with the induction of cancer cell cytotoxicity by pulsed administration of a short half-life inhibitor. Immunotherapeutics offer potential tumour-selectivity but no OAC-specific proteins have been defined. A comparative proteomic approach was employed to identify OAC-specific proteins as potential therapeutic targets. A tissue resource was established and methods to lyse fresh frozen biopsies optimised. An isobaric quantitative proteomic workflow was applied to OAC and matched normal biopsies and quantitative accuracy confirmed for 6 candidate proteins by immunohistochemistry. Proteome coverage and quantitative dynamic range were compared between isobaric and label-free systematic sequencing proteomic strategies applied to further patients’ tissues. The challenges of combining incomplete datasets were approached with a Bayesian framework to estimate the probability that a protein was missed during an experiment compared to not being present in the sample. This method was applied to generate a complete set of protein identifications and relative tissue expression. To gain insight into the dysregulated cellular processes in human OAC tissue, a network analysis was applied to the quantitative proteomic data. Enriched functional clusters were identified suggesting deranged glucose metabolism, potentially due to the Warburg effect. These findings were duplicated and candidate tumour-specific proteins identified in a further set of biopsies using the optimised quantitative proteomic method. The combined quantitative oesophageal proteomic dataset represents the largest in OAC to date. This thesis demonstrates a hypothesis-driven, synthetic lethal approach can yield cancer-selective therapeutic effects. Novel candidate therapeutic targets are also revealed through the development of quantitative proteomic methods and the application of network analysis.

published_or_final_version / abstract / Pathology / Doctoral / Doctor of Philosophy

A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Metastatic, treatment‐resistant pancreatic ductal adenocarcinoma (PDAC) is a rapidly fatal disease that typically carries a bleak prognosis. Contrast‐enhanced CT is the current standard of care tool for imaging evaluation, and repeat imaging is routinely performed in clinical trials. The availability of these imaging data render them exploitable for further analysis. CT texural analysis (CTTA), a quantitative tool for examining a region of interest on CT and generating statistical parameters based on gray‐level pixel data, is powerful technique that has been studied in other cancers and shown to correlate with features such as tumor grade, stage, and prognosis. However, the application of CTTA to PDAC has not been studied. Given the paucity of diagnostic tests to guide therapy, validated CTTA biomarkers could be immensely useful. Identifying PDAC variants that have a relative deficit in DNA repair might allow these cancers to be treated with targeted cytotoxic regimens sooner. Additionally, identifying prognostic CTTA parameters would be useful in gauging the severity of disease. We sought to perform quantitative textural analysis on CT imaging from a clinical trial cohort of patients with metastatic, treatment‐resistant PDAC. We aimed to correlate CTTA features to molecular profiling results (copy number variations obtained by array CGH) and clinical features (overall survival). Metastatic tumor sites from patients with treatment‐resistant PDAC were biopsied and molecularly profiled. Intrachromosal copy number were assessed by CGH in tumor specimens, and patients were treated based on these individual molecular profiling results. Pre‐biopsy portal‐venous phase and non‐contrast CT scans were obtained for retrospective analysis (n=15). CTTA was performed by drawing regions of interest around the primary pancreas adenocarcinoma and the normal pancreas tissue. CTTA parameters including mean positive pixels, entropy, kurtosis, and skewness were derived using the TexRAD platform at texture filtering densities of 0, 2, 3, 4, 5, and 6 pixels. CTTA values were then compared to intrachromosomal copy number variation (CNV) per tumor and overall survival (OS) post treatment using a Spearman’s rank correlation coefficient. Additional linear regression analysis was performed for positive correlations, and a Kaplan‐Meier statistic was generated for OS using median CTTA entropy. Multivariate analyses for CNV and OS were also performed. CNV were negatively correlated with the kurtosis value of the primary tumor mass using medium texture filtering (p=0.034, n=15). Linear regression revealed a significant negative correlation between kurtosis and CNV (p=0.038). Secondary analysis of the normal pancreas using coarse texture filtering revealed that increasing entropy was associated with decreased OS (p=0.0014, n=12). Using median entropy as a cutoff value (median: 4.165), median OS was greater in the entropy < 4.165 group versus the entropy > 4.165 group (179 days v 43 days; 95% CI 73.137 – 166.87; p=0.004, n=12). This exploratory study with admittedly limited sample size raises interesting questions about the use of CTTA parameters as diagnostic tools and/or biopsy adjuncts in assessing PDAC susceptibility to commercially available cytotoxics. Secondarily, entropy, a potential marker of heterogeneity and inflammation in the normal pancreas, represents an intriguing possibility for gauging prognosis.

<p>The gene BRAF is mutated to remain aberrantly activated in a large number of human malignancies, most prominently in melanoma. The most common mutation in BRAF is a missense mutation that substitutes glutamic acid for valine at codon 600 (V600E) that leads to constitutive activation of this kinase. In this active state, BRAFV600E phosphorylates and activates the MEK1 and MEK2 kinases, which in turn phosphorylate the ERK1 and ERK2 kinases of the MAPK pathway to promote tumorigenesis. Targeting this pathway is a well-validated strategy to treat BRAF-mutant cancer. Inhibitors of both BRAFV600E and the MEK1/2 kinases are used to treat BRAF-mutant melanoma and are being evaluated in other cancers as well. However, the duration of response to these targeted therapies is limited by innate and acquired resistance, which is often mediated through reactivation of the MAPK pathway. Thus, new targeted therapies to inhibit MAPK signaling in BRAF-mutant malignancies are required. To this end, MEK1/2 kinases require copper (Cu) for enzymatic activity and signaling. We therefore tested whether the dependency of these validated targets on Cu could be leveraged for the treatment of BRAF-mutant cancer.</p><p>We report that genetic reduction of Cu import through disruption of the gene encoding the high affinity Cu transporter CTR1 or pharmacological chelation of Cu with the drug tetrathiomolybdate (TTM) suppressed MAPK signaling in both in vitro and in vivo models of BRAF-mutant tumorigenesis. This reduction in MAPK signaling correlated with a reduced potential for tumorigenic growth and an increase in survival of tumor-bearing mice. Finally, TTM reduced the transformed growth of a number of human melanoma cell lines engineered to be resistant to current MAPK pathway inhibitors. As such, Cu chelation holds promise as a novel treatment for BRAF-mutant cancers and may find value in targeting resistance to current MAPK pathway inhibitors.</p> / Dissertation

El presente trabajo de investigación ha sido concebido ,en primer lugar ,para despertar la conciencia preventiva de salud en las autoridades del Hospital Hipólito Unanue y de la población que este atiende, dándoles a conocer mediante sus resultados ,el estado actual que presenta la enfermedad ácido péptica de la mucosa gástrica en la población atendida en este hospital y su relación con la presencia infectante del germen denominado: Helicobacter pílori lo cual por su magnitud puede ser considerado un problema de salud pública de tipo endémico ,en nuestro medio . De otro lado creo justificada la realización de este trabajo en el hecho de que una réplica de los estudios ya realizados, sobre esta materia ,no se ha hecho en nuestro hospital desde el punto de vista antomopatológico y contando además con una alta casuistica estudiada en nuestro laboratorio espero poder contribuir a ampliar y esclarecer un poco mas los conocimientos ya logrados en otros ámbitos de estudio.