INTRODUÇÃO: O câncer colorretal metastático (CCRm) é uma doença clinicamente e molecularmente heterogênea. Os pacientes apresentam diferentes prognósticos e respostas variáveis às terapias direcionadas contra o tumor. Alterações na função do sistema de reparo do DNA (deficiency mismatch repair - dMMR) estão associadas com o fenótipo de instabilidade de microssatélites e bom prognóstico em tumores de estádio inicial. No entanto, dMMR é raro no CCRm e pouco se sabe sobre sua influência na taxa de resposta (TR) ao tratamento. Nosso objetivo primário foi comparar a TR, de acordo com o status dMMR, nos pacientes com CCRm. Os desfechos secundários foram TR, conforme RAS e BRAF mutados, e a sobrevida global (SG), de acordo com dMMR. MÉTODOS: Estudo retrospectivo com grupo controle que comparou a TR por RECIST 1.1 em pacientes com CCRm, tratados com quimioterapia (QT) sistêmica, de acordo com o status dMMR. Os dados clínicos foram coletados, retrospectivamente, dos prontuários médicos. Todas as imagens foram digitais e recuperadas para avaliação de resposta por um único radiologista, cego quanto ao status dMMR. dMMR foi definido como a perda de expressão imuno-histoquímica em pelo menos um dos genes MMR (MLH1, MSH2, MSH6 e PMS2). Mutações em RAS e BRAF foram investigadas por meio de sequenciamento gênico. Os casos foram os pacientes com dMMR, e os controles, com MMR proficiente (pMMR), selecionados de forma consecutiva, em proporção de 1:2. Com base em características clínicas e moleculares, os indivíduos dMMR foram classificados como provável Lynch ou dMMR esporádico. Estatística descritiva foi usada para resumir os resultados. A associação entre dMMR e os resultados específicos de cada grupo foram analisados pelo teste do qui-quadrado, e para a avaliação de SG mediana, curvas de Kaplan-Meier e teste log-rank foram utilizados. Valores bicaudados de p < 0.05 foram considerados significativos. RESULTADOS: Entre janeiro de 2009 e janeiro de 2013, de 1270 pacientes, 762 foram elegíveis e rastreados para dMMR: N = 27 (3,5%) tiveram dMMR e N = 735 (96,5%) tiveram pMMR. Dada a raridade, foram incluídos 14 indivíduos com dMMR fora do período de inclusão, totalizando 41 casos (pacientes dMMR) e 84 controles (pacientes pMMR). Em análise por intenção de tratamento, considerando os pacientes que receberam pelo menos uma dose de QT baseada em oxaliplatina (N dMMR = 34), aqueles com dMMR apresentaram TR numericamente menor, comparados aos pMMR (11.7% vs 28.6%, OR: 0.33, IC 95%: 0.08-1.40, p = 0.088). Em análise por protocolo, incluindo apenas os pacientes que preencheram os critérios de inclusão (N dMMR = 33), aqueles com dMMR mantiveram TR menor à QT baseada em oxaliplatina em primeira linha, em comparação aos doentes pMMR, embora estatisticamente não significante (12.1% vs 28.6 %, OR: 0.34, IC 95%: 0.09-1.18, p = 0.102). Ainda neste contexto, os pacientes com possível Lynch apresentaram maior TR do que os indivíduos com provável dMMR esporádico (16% vs 0). Mutações em RAS ou BRAF não influenciaram na TR ou sobrevida. O status \"provável dMMR esporádico\" foi fator de pior prognóstico, quando todos os pacientes da amostra (N dMMR = 41) foram considerados. CONCLUSÃO: Este estudo sugere que dMMR é preditivo de resistência à quimioterapia baseada em oxaliplatina, como mostrado por outros estudos. Aparentemente, essa resistência é mais acentuada nos pacientes dMMR esporádicos, sugerindo heterogeneidade biológica nos doentes com CCRm e dMMR / BACKGROUND: Metastatic colorectal cancer (mCRC) is a clinically and molecularly heterogeneous disease, where patients present different prognosis and variable responses to cancer-directed therapies. Alterations in the function of DNA deficiency mismatch repair (dMMR) genes are associated with microsatellite instability and good prognosis in early stage tumors. However dMMR dysfunction is rare in mCRC and little is known about its influence on treatment response rate (RR). Our primary endpoint was to compare the RR of mCRC patients according to dMMR status and to explore differences between patients with likely sporadic versus likely Lynch-related tumors. Secondary endpoints were RR according to RAS and BRAF mutation status, and survival times as per dMMR status. METHODS: Retrospective study with control group that compared the RR by RECIST 1.1 in patients with mCRC treated with systemic chemotherapy according to dMMR status. Clinical data were collected retrospectively from medical charts. All images were digital and were retrieved for response evaluation by a single radiologist blinded to dMMR results. dMMR status was defined as loss of immunohistochemistry expression in at least one of the MMR genes (MLH1, MSH2, MSH6 e PMS2). RAS and BRAF mutations were investigated through next generation sequencing. Cases were defined as dMMR and controls, as proficient MMR (pMMR) patients, in a 1:2 fashion. Based on clinical and molecular features, dMMR patients were classified as likely Lynch or sporadic. Descriptive statistics was used to summarize the results. The association between dMMR and outcomes of each group were analyzed by chi-square test; estimates of median overall survival were done by the Kaplan-Meier method and comparisons, by the log-rank test. Two-tailed p values < 0.05 were considered significant. RESULTS: From January 2009 to January 2013, out of 1270 patients, 762 were eligible and screened for dMMR: N = 27 (3.5%) had dMMR and N = 735 (96.5%) had pMMR. Given the rarity, 14 dMMR cases outside the inclusion period were included, with a total of 41 cases (dMMR patients) and 84 controls (pMMR patients). By intention-to-treat analysis, considering all patients who received at least one dose of oxaliplatin-based chemotherapy (N dMMR = 34), those with dMMR had numerically lower RR, compared with pMMR (RR = 11.7% vs 28.6%, OR: 0.33, 95% CI: 0.08-1.40, p = 0.088). As per protocol analysis, considering only the patients who met inclusion criteria (N dMMR = 33), those with dMMR status persisted with numerically, but non-significant, lower RR to first-line oxaliplatin-based chemotherapy compared with pMMR (12.1% vs 28.6%, OR: 0.34, 95% CI: 0.09-1.18, p = 0.102); also, patients with likely Lynch-related mCRC presented higher RR than subjects with probable sporadic dMMR (16% vs 0). Either survival or RR was influenced by RAS or BRAF mutations. Probable sporadic dMMR status was a poor prognostic factor when all patients in the sample (N dMMR = 41) were analyzed. CONCLUSION: This study suggests that the dMMR phenotype is predictive of resistance to oxaliplatin-based chemotherapy, as shown by other studies. Apparently, such resistance is more pronounced in the sporadic dMMR patients, suggesting biological heterogeinity within the dMMR mCRC patients

L’hypothèse prédominante de cette thèse est que les changements métaboliques tumoraux mesurés par FDG-PET/CT sous l’influence des traitements anticancéreux, apparaissent plus précocement et parfois exclusivement par rapport aux modalités d’imagerie morphologique classique. L’imagerie multimodale, en combinant les avantages de chacune des techniques, dépasse leur limitations et pourrait permettre (i) une évaluation du bénéfice du traitement plus rapide et plus adéquate ;(ii) de modifier les algorithmes thérapeutiques à différents stades de cancer colorectal et (iii) d’améliorer la compréhension des mécanismes d’échappement aux traitements anticancéreux. Pour évaluer l’apport de l’imagerie multimodale dans l’évaluation de la réponse au traitement des cancers colorectaux (CCR), nous avons poursuivi 3 séries d’expérimentation cliniques.<p><p>1) Le premier projet explore l’imagerie multimodale comme un outil d’individualisation pour la radio-embolisation (microsphères chargées en 90Yttrium) chez des patients porteurs d’un CCR métastatique au niveau du foie, pour laquelle l’imagerie morphologique classique est incapable de mesurer l’effet thérapeutique. Nous montrons que l’usage non sélectif de la radio-embolisation améliore l’histoire clinique de ces patients, bien que certains d’entre eux ne semblent pas en bénéficier. Ensuite, par une analyse multimodale lésion par lésion intégrant angiographie-CT Scan, FDG-PET/CT et scintigraphie aux macro-agrégats d’albumine marqués au 99mTechnetium, nous démontrons que la distribution pré-thérapeutique des macro-agrégats d’albumine est hétérogène entre les différentes lésions des patients et prédictive de la réponse métabolique au sein de ces lésions, permettant le développement d’un outil de prédiction et de planification pour la radio-embolisation.<p><p>2) Le deuxième projet explore le domaine du CCR métastatique traité par chimiothérapie palliative. (i) Nous démontrons d’abord que la réponse métabolique (RM) tumorale après une cure de chimiothérapie cytolytique prédit plus vite et plus adéquatement que l’imagerie morphologique basée sur les critères RECIST les bénéfices cliniques du traitement. La RM précoce a une excellente valeur prédictive négative sur l’absence de réponse morphologique et met en évidence une variabilité de réponse inter-lésionnelle chez une proportion importante des patients. (ii) L’étude SoMore explore ensuite des patients présentant un CCR avancé et réfractaire, traités par capecitabine et sorafenib, et confirme l’importance pronostique des RM mixtes, suggérant une méthodologie de classification clinique basée sur la consistance de la RM. (iii) Cette classification cherche confirmation dans l’étude RegARd-C, encore en cours, évaluant les effets du regorafenib, et explorant également la signification génomique et épigénétique de la variabilité de RM. <p><p>3) Le troisième projet cherche à utiliser les propriétés de l’imagerie métabolique pour modifier l’algorithme de traitement adjuvant des patients porteurs d’un cancer du côlon de stade III. Ce projet, encore en cours, fait l’hypothèse que l’absence de RM de la lésion primitive après une cure de chimiothérapie prédit l’absence de bénéfice du traitement adjuvant complet. Une analyse intérimaire en démontre la faisabilité et confirme la présence de 40% de tumeurs présentant des caractéristiques métaboliques de chimio-résistance.<p><p>En conclusion, pour des patients porteurs d’un CCR, l’imagerie multimodale comprenant une évaluation du métabolisme tumoral permet une évaluation plus précoce et plus adéquate du bénéfice au traitement anticancéreux pour différentes modalités thérapeutiques comme la radio-embolisation, la chimiothérapie cytotoxique et les agents biologiques. L’imagerie multimodale permet de prédire et planifier les radio-embolisations et se révèle très prometteuse pour les traitements chimiothérapiques cytotoxiques ou combinés à des biologiques en situation adjuvante ou métastatique. Elle démontre par ailleurs une importante variabilité de réponse métabolique inter-lésionnelle qui représente un axe de recherche majeur sur les mécanismes moléculaires d’hétérogénéité génomique tumorale et de résistance aux traitements anti-cancéreux.<p> / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished

The thesis discusses the methods of determination of tumor markers and their clinical importance in medical diagnostics. The theoretical part describes clinically important tumor markers and also the chemiluminescent immunoassay methods used for their determination. The practical part of the thesis describes the introduction of new chemiluminescent methods for the determination of tumor markers in routine operation, evaluates its basic analytical parameters and compares it with the existing immunoturbidimetric method. The practical part also presents results of monitoring of cancer patients with various tumors, which is performed by evaluation of the values of tumor markers. Comparison of our method with other methods within the context of System of external quality control is also documented.

Utilisation of New Biomarkers for the Optimalization of Diagnostics and Therapy of Tumors of the Gastrointestinal Tract Introduction: Tumor markers are standard diagnostic tools. They are mainly used to monitor the course of the disease and to check the efficacy of the treatment. It is important to observe dynamics. Changing the level of the biomarker can prevent clinical manifestation and lead to early diagnosis of relapse, which in turn means improving the quality of life, including prolonging survival. Recently, we have encountered a number of diagnostic algorithms that suggest algorithms for estimating the risk of tumor presence or the risk of progression of cancer, using statistical methods. Objectives: The aim of this work is to verify new biomarkers for the diagnosis of gastric cancer and to develop an optimal algorithm for their use. Further, to evaluate the importance of cytokeratin markers - Tissue Polypeptide Antigen (TPA) and Tissue Polypeptide Specific Antigen (TPS) for the diagnosis of metastatic colorectal carcinoma in the liver. To carry out a pilot study of FGF23 levels in people with colorectal carcinoma and other gastrointestinal tumors. Methods and patients: Patient samples were analyzed using immunoradiometric, chemiluminescence and fluorescence assays. For each solved problem,...

Genomic integrity is important for living cells' correct functioning and propagation. Deoxyribonucleic acid as a molecule is a subject to chemical reactions with agents that can come from environment as well as from internal metabolism processes. These reactions can induce damage to DNA and thus compromise the genetic information, and result in disease and death of an organism. To mitigate the damage to DNA, cells have evolved to have multiple DNA repair pathways. Presented here is a computational study of DNA repair genes. The structure of the Homo sapiens direct DNA repair gene ALKBH1 is predicted utilizing homology modeling methods and using AlkB and DBL proteins as templates. Analysis of the obtained structure and molecular dynamics simulations give insights into potentially functionally important residues of the protein. In particular, zinc finger domains are predicted, and lysines that could perform catalytic activities are investigated. Subsequent mutagenesis experiments revealed the effect of the residues predicted to form zinc fingers on activity of ALKBH1. Structure and dynamics of AlkD, a Bascillus cereus base excision DNA repair protein is also studied. This protein has been shown to bind DNA with large alkyl adducts and perform excision catalysis without base flipping which is characteristic to other enzymes in the same family. MD simulations of AlkD revealed that B helix, which interacts with DNA, has higher fluctuations when AlkD is not bound to DNA, and thus could have a role in binding and recognition of DNA. For the purpose of finding biomarkers and to further our understanding of a mode of action of DNA repair genes, statistical methods were applied to identify mutations that are linked to cancer phenotypes. Analysis was based on case-control studies of patients with cancers of prostate, breast, pancreas, lung as well as chronic lymphocytic leukemia from NCBI dbGAP database. Those mutations that result in missense mutations were further investigated. In particular, extensive MD simulations and experimental investigations were performed on the mutation in the ALKBH7 gene that was found to be linked to prostate cancer.

Utilisation of New Biomarkers for the Optimalization of Diagnostics and Therapy of Tumors of the Gastrointestinal Tract Introduction: Tumor markers are standard diagnostic tools. They are mainly used to monitor the course of the disease and to check the efficacy of the treatment. It is important to observe dynamics. Changing the level of the biomarker can prevent clinical manifestation and lead to early diagnosis of relapse, which in turn means improving the quality of life, including prolonging survival. Recently, we have encountered a number of diagnostic algorithms that suggest algorithms for estimating the risk of tumor presence or the risk of progression of cancer, using statistical methods. Objectives: The aim of this work is to verify new biomarkers for the diagnosis of gastric cancer and to develop an optimal algorithm for their use. Further, to evaluate the importance of cytokeratin markers - Tissue Polypeptide Antigen (TPA) and Tissue Polypeptide Specific Antigen (TPS) for the diagnosis of metastatic colorectal carcinoma in the liver. To carry out a pilot study of FGF23 levels in people with colorectal carcinoma and other gastrointestinal tumors. Methods and patients: Patient samples were analyzed using immunoradiometric, chemiluminescence and fluorescence assays. For each solved problem,...

O câncer de mama é a principal causa de mortalidade por câncer entre as mulheres. Alguns biomarcadores e características clínicas são utilizados para avaliar o prognóstico e prever a resposta a uma série de abordagens terapêuticas. A Homocisteína é conhecida como um fator de risco para doença vascular aterosclerótica, mas sua participação na biologia do câncer ainda é incerta. Cisteína é o aminoácido sulfurado derivado da Homocisteína no ciclo da Metionina. Este ciclo metabólico origina as bases nitrogenadas e também determina o nível de metilação da molécula de DNA. É atualmente reconhecido que a hipometilação global do genoma é um evento chave na transformação maligna das células. O objetivo deste estudo foi avaliar os níveis séricos de homocisteína e cisteína como biomarcadores de sobrevida e de progressão da doença em câncer de mama. Também foi avaliado o efeito de um curso de curta duração (um mês) de tratamento hormonal sobre os níveis de Homocisteína, Cisteína e metilação do DNA. Amostras de sangue foram obtidos por ocasião da biópsia inicial (pré-tratamento) em todas as pacientes e, de tumor e de tecido normal adjacente, ao diagnóstico eem um mês após, para as pacientes que receberam o regime hormonal neo-adjuvante (pré-operatório). Todas as pacientes eram mulheres na pós-menopausa, com tumores de mama ressecáveis, acompanhadas em dois hospitais públicos, que consentiram em participar de outros dois protocolos de pesquisa prévios. Homocisteína e Cisteína foram analisadas por HPLC e a metilação global do DNA do tecido foi determinada por meio da técnica de MSRE (Methylation-Sensitive Restriction Enzyme). Foi observada uma diferença significativa entre os níveis pré e póstratamento de Homocisteína e Cisteína em tumores avançados, sugerindo um papel prognóstico em pacientes com características clínicas reservadas. As variações nos níveis de Homocisteína se mostraram significativamente correlacionadas com a sobrevida livre de doença. O modelo de risco proporcional de Cox demonstrou que os níveis de homocisteína e o status dos linfonodos representaram fatores prognósticos independentes em termos de sobrevida livre de doença. Embora mais estudos sejam necessários para confirmar estes resultados, nossa pesquisa sugere que a Homocisteína pode ser usada como um biomarcador de prognóstico para câncer de mama / Breast cancer is the leading cause of cancer mortality among women. Some biomarkers and clinical features are used to evaluate prognosis and to predict response to a range of therapeutic approaches. Homocysteine is well known as a risk factor in atherosclerotic vascular diseases, but its participation in cancer biology is still unclear. Cysteine is a sulfur amino acid derived from Homocysteine in the Methionine cycle. This metabolic cycle originates the nitrogenous bases and determines the methylation level of the DNA molecule as well. It is currently recognized that the global hipomethylation of the genome is a key event in the malign transformation of cells. The aim of this study was to evaluate serum Homocysteine and Cysteine as biomarkers of survival and disease progression in breast tumor, as well as the methylation status of tumor and normal tissues. The effect of a short course (one month) of hormonal treatment on Homocysteine, Cysteine and DNA methylation levels was also evaluated. Blood samples were collected during the initial biopsy (pretreatment) in all patients and, tumor samples and normal adjacent tissue, at diagnosis and one month after, for the patients that received neo-adjuvant hormonal regimen (pre-treatment). All patients were post-menopausal women, with resectable breast tumors, followed at two public hospitals, and that had consented to participate in two previous research protocols related to their disease. Serum Homocysteine and Cysteine were analyzed by HPLC and tissue global DNA methylation was determined by the MSRE (Methylation- Sensitive Restriction Enzyme) technique. A significant difference was observed between pre- and post-treatment levels of Homocysteine and Cysteine in advanced tumors, suggesting a prognostic role in patients with poor clinical characteristics. Variations in Homocysteine levels were significantly correlated with disease free survival. Cox proportional risk model demonstrated that nodal status and Homocysteine levels were independent prognostic factors for Disease Free Survival. Although more studies are needed to confirm these results, our research suggests that Homocysteine might be used as a prognostic biomarker for breast cancer

O desenvolvimento e invasão de tumores cerebrais primários são diretamente influenciados pela matriz extracelular. Considerando que lisil oxidase (LOX) e os demais membros da família das lisil oxidases (LOXL1, LOXL2, LOXL3 e LOXL4) apresentam complexidade tanto estrutural quanto funcional e estão envolvidos em processos biológicos vitais, como motilidade celular, sinalização celular e regulação gênica, a desregulação da expressão destas proteínas pode levar à gênese e progressão tumoral. O presente trabalho teve como objetivos avaliar os níveis de expressão dos genes que codificam todos os membros da família das lisil oxidases em astrocitomas de diferentes graus de malignidade e correlacionar com a expressão de BMP1 e HIF1A, mutação de IDH1 e tempo de sobrevida total dos pacientes. Adicionalmente, as expressões das proteínas codificadas por estes genes foram também realizadas, além de um estudo funcional in vitro do papel de LOX em astrocitomas. A análise da expressão dos genes foi realizada por PCR quantitativa em tempo real numa série de 153 astrocitomas e 22 amostras de tecido cerebral não neoplásico. A expressão proteica foi conduzida por imuno-histoquímica em amostras de astrocitomas. O silenciamento da expressão de LOX foi realizado em linhagens celulares de glioblastoma humano U87MG e A172 transfectadas com o siRNA para os ensaios funcionais. A expressão de todos os genes (LOX, LOXL1, LOXL2, LOXL3, LOXL4, BMP1 e HIF1A) aumentou com o grau de malignidade dos astrocitomas, com maiores níveis nos casos de glioblastoma. Foi encontrada uma correlação positiva nos valores de expressão dos genes principalmente nos glioblastomas. Somente a expressão de LOXL3 teve um impacto na sobrevida dos casos com GBM. Pacientes com maior expressão apresentaram maior sobrevida em relação aos com menor expressão de LOXL3. Os casos de astrocitoma grau II com mutação de IDH1 apresentaram menor expressão de LOXL1 e de LOXL4 quando comparados com os casos sem mutação. Os casos de GBM com mutação de IDH1, por sua vez, apresentaram menores níveis de expressão de LOX e de LOXL1 do que os casos sem IDH1 mutado. Os níveis de expressão das proteínas da família das lisil oxidases também estavam maiores nas amostras de glioblastoma, com localização nuclear e citoplamastica das células, além de marcação do endotélio. Interessantemente, um caso de glioblastoma com mutação de IDH1 apresentou menor expressão de LOX, inclusive nas células endoteliais. Nas análises funcionais, o silenciamento de LOX por siRNA e o tratamento com o inibidor BAPN das linhagens celulares U87MG e A172 afetaram a capacidade de migração. Além sito, a menor expressão de LOX afetou a capacidade de invasão e crescimento independente de ancoragem das células. Em conjunto, esses resultados corroboram o papel de LOX em processo importantes da tumorigênese dos astrocitomas. Adicionalmente, a expressão de LOX é influenciada pelo status de mutação de IDH1. Portanto, este trabalho fornece novas informações para as possíveis intervenções terapêuticas para o tratamento dos pacientes com astrocitomas / The development and invasion of primary brain tumors are directly influenced by the extracellular matrix. Considering that lysyl oxidase (LOX) and other lysyl oxidase family members (LOXL1, LOXL2, LOXL3 e LOXL4) have both structural and functional complexity and that they are involved in vital biological processes such as cell motility, cell signaling and gene regulation, a deregulation of these proteins can lead to the genesis and tumor progression. This study aimed to evaluate the expression levels of genes that code for the lysyl oxidase family members in astrocytomas of different malignant grades and to correlate to the expression of BMP1 and HIF1A, IDH1 mutation and overall patients\' survival. Moreover, protein expression coded by these genes was also analyzed, besides an in vitro functional study of LOX role in astrocytomas. Gene expression analysis was performed by quantitative real-time PCR in a series of 153 astrocytomas and 22 samples of non-neoplastic brain. Protein expression was analyzed by immunohistochemistry in astrocytoma samples. LOX knockdown was performed in cells of human glioblastoma U87MG and A172 transfected with siRNA. Expression levels of all genes (LOX, LOXL1, LOXL2, LOXL3, LOXL4, BMP1 e HIF1A) increased with the malignant grade of astrocytomas, glioblastomas presenting the higher levels. Positive correlations of gene expression values were observed specially in glioblastomas. Only LOXL3 expression impacted in the overall survival of glioblastoma cases. Patients with higher expression presented longer survival time than those with lower LOXL3 expression. Astrocytoma grade II cases with IDH1 mutation presented lower LOXL1 and LOXL4 expression when compared to those cases with wild type IDH1. On the other hand, GBM cases with IDH1-mutated presented lower LOX and LOXL1 expression than GBM cases without IDH1 mutation. Protein expression levels of lysyl oxidase family members were also higher in glioblastoma samples, with both nuclear and cytoplasmic localization, and also endothelium staining. Interestingly, a glioblastoma case with IDH1-mutated had lower LOX expression, including endothelial cells. For functional analysis, LOX knockdown by siRNA and treatment with inhibitor BAPN of U87MG and A172 cell lines affected migration behavior. Furthermore, lower LOX expression affected invasion capacity and anchorage independent growth. Altogether, these results corroborate LOX role in important processes of astrocytoma tumorigenesis. Additionally, LOX expression is influenced by IDH1 mutational status in glioblastomas. Therefore, our work provides new insights for possible therapeutic interventions for patients with astrocytomas

Ependimomas são tumores gliais raros. Podem ser encontrados em qualquer localização do sistema nervoso central e, apesar de histologia similar, parecem apresentar alterações genômicas distintas. As variáveis clínicas são intercorrelacionadas e, geralmente, incapazes de predizer o curso da doença. O objetivo do presente estudo foi analisar a expressão aumentada de genes e proteínas em ependimomas e correlacionar com dados clínicos dos pacientes. Foram estudados casos de pacientes com ependimoma submetidos à ressecção cirúrgica no Hospital das Clínicas, Universidade de São Paulo, no período entre 1996 e 2011 (33 amostras de tecido congelado para análise de expressão gênica por PCR quantitativo em tempo real e 149 amostras com tecido incluído em parafina, correspondentes a 121 casos devido a recidivas, para análise de proteína por imuno-histoquímica de tissue microarrays). As reações de imuno-histoquímica foram analisadas semiquantitativamente e graduadas com um índice de marcação calculado pelo produto da porcentagem de núcleos marcados pela intensidade de marcação. Oitenta e um casos eram adultos (média de 27,2 anos). Havia 60 casos intracranianos e 61 intramedulares, dos quais 10 eram mixopapilares, 92 grau II e 19 grau III. Ressecção completa foi possível em 62% dos casos e recidiva foi confirmada em 41,1%. Observou-se menor tempo para recidiva em crianças e tumores intracranianos, supratentoriais (p < 0,001 em ambos), histologia anaplásica e ressecções incompletas (p < 0,05 em ambos). Os seguintes genes foram selecionados em dados públicos de SAGE e literatura: ARMC3, CCND1, CHST5, DNALI1, FGFRL1, GNA13, IGF2, MSX1, NOTCH1 e RSPH3. ARMC3, RSHL3, CHST5 e DNALI1 apresentaram maiores níveis de expressão em ependimomas intramedulares (p < 0,05), e FGFRL1, NOTCH1 e CCND1 nos casos supratentoriais (p < 0,01). IGF2 apresentou maiores níveis de expressão em crianças e CHST5 em adultos (p < 0,05 em ambos). Foram observados maiores níveis de expressão de FGFRL1 (p < 0,05), CCND1 e IGF2 (p < 0,01 em ambos) em casos com histologia anaplásica. Nenhum dos genes analisados apresentou impacto no tempo livre de progressão ou na sobrevida. A expressão da proteína codificada por CCND1, ciclina D1, também foi avaliada por imuno-histoquímica, por ser uma proteína com expressão aumentada em diversos tipos de neoplasias e não ter ainda um valor prognóstico bem estabelecido em ependimomas. Houve correlação entre expressão de ciclina D1 a nível de mRNA e da proteína (p < 0,0001). As correlações entre ciclina D1 e histologia anaplásica e localização supratentorial foram confirmadas pela análise proteica (p < 0,0001 em ambos). Adicionalmente, foi também observada maior expressão de ciclina D1 em pacientes mais jovens (p < 0,01). A maior expressão de ciclina D1 em tumores com localização supratentorial foi independente do grau histológico e da idade do paciente. Recidiva foi mais frequente em casos com maiores níveis de expressão de ciclina D1 (p < 0,05), embora uma maior correlação com tempo livre de progressão foi observada apenas em casos com ressecção completa (p < 0,001). Os ependimomas apresentaram expressão gênica diferencial de acordo com idade, localização do tumor e grau histológico nesse estudo. A determinação dos níveis da expressão de ciclina D1 pode ser útil para guiar o seguimento e tratamento dos casos supratentoriais com ressecções completas / Ependymomas are rare glial cell-derived tumors. They can be found in any central nervous system localization and despite the histological similarity, they seem to display distinct genomic abnormalities. Clinical variables are intercorrelated and they are usually unable to predict the disease course. We aimed to analyze increased gene and protein expression in ependymomas and to correlate with patients\' clinical data. We studied patients with ependymoma submitted to surgical resections at Hospital das Clinicas, University of São Paulo, from 1996 to 2011 (33 fresh-frozen samples for gene expression analysis by quantitative real-time PCR and 149 formalin-fixed, paraffin-embedded samples, relative to 121 patients due to relapses, for protein analysis by tissue microarray immunohistochemistry). Immunohistochemical reactions were analyzed semi-quantitatively and scored with a labeling index (LI) calculated as the product of the percentage of the positively stained nuclei by the intensity of staining. Eighty-one cases were adults (mean 27.2 years). There were 60 intracranial and 61 spinal cases, of which 10 tumors were myxopapillary, 92 were grade II and 19 were grade III. Gross total resection was achieved in 62% of cases and relapse was confirmed in 41.4% of cases. We observed a shorther time to relapse in children and supratentorial intracranial tumor localization (p<0.001 for both), anaplastic histology and incomplete resections (p<0.05 for both). The following genes were selected based on public SAGE database and literature: ARMC3, CCND1, CHST5, DNALI1, FGFRL1, GNA13, IGF2, MSX1, NOTCH1 and RSPH3. ARMC3, RSHL3, CHST5 and DNALI1 presented higher expression levels in intramedullary ependymomas (p < 0.05) and FGFRL1, NOTCH1 and CCND1 in supratentorial cases (p < 0.01). IGF2 presented higher expression levels in pediatric cases and CHST5 in adults cases (p < 0.05 in both). Higher expression levels of FGFRLI1 (p < 0.05), CCND1 and IGF2 (p < 0.01 for both) were observed in anaplastic histology cases. None of the genes impacted in progression free survival or overall survival of patients. The expression of protein codified by CCND1, cyclin D1, was also evaluated by immunohistochemistry, because its overexpression has been related with several types of neoplasias and its prognostic value has not yet been fully established in ependymomas. There was a correlation of cyclin D1 expression at mRNA and protein levels (p < 0.0001). Correlations between cyclin D1 and anaplastic histology and supratentorial localization were confirmed by protein analyses (p < 0.0001 for both parameters). Additionally, high expression of cyclin D1 was observed in younger patients (p < 0.01). The higher cyclin D1 expression in supratentorial tumor localization was independent of histological grade and age of patient. Relapse was more frequent in cases with higher cyclin D1 expression levels (p < 0.05) although correlation with progression free survival was just observed in gross total resection cases (p < 0.001). Ependymomas presented differential gene expression according to age, tumor localization and histological grade in our study. Determination of cyclin D1 expression levels may be useful to guide follow-up and treatment in supratentorial cases with gross total resection

Introdução: O câncer de mama é, em sua essência, uma doença genética. O acúmulo de alterações moleculares no genoma das células somáticas é a base para a progressão do câncer. Além de ter biologia natural mais favorável, os tumores com alta expressão de receptores de estrogênio têm terapia-alvo bem estabelecida. Apesar disso, as pacientes podem apresentar resistência medicamentosa, recidiva e óbito. Os microRNAs (miRNAs) são uma classe de pequenas moléculas não codificadoras de proteínas que regulam a expressão gênica durante a etapa de tradução. Esta regulação é feita pelo pareamento de bases com o mRNA-alvo (RNA mensageiro), resultando na supressão da tradução ou na clivagem do mRNA. Se os miRNAs têm como alvo genes supressores de tumor ou oncogenes, podem atuar como supressores tumorais ou oncogenes. OBJETIVO: avaliar a expressão de microRNAs, por PCR em tempo real, no carcinoma mamário ductal invasivo (CDI) com receptores hormonais positivos e HER-2 negativo (luminal A). MÉTODOS: Foram avaliados materiais em parafina de 33 pacientes com tumores luminal A, bem como tecido mamário histologicamente normal. Foram utilizados kit para extração de RNA de amostras fixadas e parafinadas - miRNeasy FFPE; kit para síntese de cDNA - miScript II RT; kit miScript SYBR Green PCR e miScript miRNA PCR Arrays para análise de 84 sequências de miRNA de câncer humano. Analisaram-se dados clínicos, como idade, paridade, amamentação, estado menopausal; variáveis histológicas, como tamanho do tumor, estado linfonodal, invasão linfática; características imunoistoquímicas, como expressão de Ki-67. Para a análise estatística utilizou-se o software miScript miRNA PCR Array Data Analysis, que emprega o método de quantificação relativa ??Ct. RESULTADOS: A análise comparativa dos 33 casos de CDI luminal A com os 15 casos de parênquima mamário normal revelou haver microRNAs hiperexpressos, sendo eles: miR-96-5p (fold-regulation = 9,245, p = 0,000192), miR-182-5p (fold-regulation = 6,4813, p = 0,00024), miR-21-5p (fold-regulation = 6,3129, p = 0,000001), miR- 210-3p (fold-regulation =4,3584, p =0,001002) e. miR-7-5p (fold-regulation = 4,0166, p = 0,036407). Apontou, ainda, microRNAs com hipoexpressão, a saber: miR-204-5p (Fold-regulation = -8,2104, p = 0,000000), miR-125b-5p (Fold-regulation = --6,332, p=0,000000), let-7c-5p (Fold-regulation: -4,5142, p=0,000000) e let-7e-5p (Fold-regulation = -4,059, p = 0,011625): CONCLUSÕES: CDI luminal A apresentou hiperexpressão de miR-96-5p, miR-182-5p, miR-21-5p, miR-210-3p e miR-7-5p. Apontou, ainda, hipoexpressão do miR-204-5p, miR-125b-5p, let-7c-5p e let-7e-5p, permitindo diferenciá-lo do tecido normal / INTRODUCTION: Breast cancer is a genetic disease and the accumulation of molecular alterations in the genome of somatic cells is the basis for cancer progression. Besides having a more favorable natural biology, tumors with high expression of estrogen receptor have a well established targeted therapy. Nevertheless, patients may present with resistance and eventually relapse and death. MicroRNAs (miRNAs) are a class of small non-coding protein molecules that regulate gene expression during the translation stage. This adjustment is made by base pairing with the mRNA (messenger RNA) target resulting in suppression of translation or cleavage of the mRNA. Depending on whether miRNAs target tumor suppressor genes or oncogenes, they can act as tumor suppressors or oncogenes. OBJECTIVE: evaluate the expression of microRNAs by RT-PCR in positive hormonal receptors, negative HER 2 (luminal A) invasive ductal carcinoma (IDC). METHODS: Paraffin embedded tumor material from 33 patients with luminal A IDC, and histologically normal breast tissue. Were used: Kit for RNA extraction from fixed and paraffin embedded samples - miRNeasy FFPE; cDNA synthesis kit - miScript II RT; miScript SYBR Green PCR Kit and miScript miRNA PCR Arrays for analysis of 84 miRNA sequences of human cancer. Clinical data such as age, parity, breastfeeding, menopausal status; histological variables such as tumor size, lymph node status, lymphatic invasion; immunohistochemical characteristics, such as expression of Ki-67, were evaluated. For statistical analysis the miScript miRNA PCR Array Data Analysis software, which uses the method of relative quantification ??Ct, was used. RESULTS: A comparative analysis of 33 cases of luminal A IDC with 15 cases of normal breast parenchyma defined microRNAs overexpressed, as follows: miR-96-5p (fold-regulation = 9,245, p = 0,000192), miR-182-5p (fold-regulation = 6,4813, p = 0,00024), miR-21-5p (fold-regulation = 6,3129, p = 0,000001), miR- 210-3p (fold-regulation =4,3584, p =0,001002) and miR-7-5p (fold-regulation = 4,0166, p = 0,036407). Furthermore, microRNAs with reduced expression, as follows:. miR-204-5p (Fold-regulation = -8,2104, p = 0,000000), miR-125b-5p (Fold-regulation = -6,332, p=0,000000), let-7c-5p (Fold-regulation: -4,5142, p=0,000000) and let-7e-5p (Fold-regulation = -4,059, p = 0,011625): CONCLUSION: Luminal A CDI breast cancer has shown overexpression of miR-96-5p, miR-182-5p, miR-21-5p, miR-210-3p and miR-7-5p. Also has shown,downregulation of miR-204-5p, miR-125b-5p, let-7c-5p e let-7e-5p, allowing differentiating it from normal tissue