Como vemos en la práctica diaria, las neoplasias tienen comportamientos muy distintos. En la era de los nuevos marcadores pronósticos seguimos buscando cualquier dato de la paciente o del tumor que nos pueda ayudar a clasificar a la paciente como bajo o alto riesgo intentando “predecir” como va a responder a tratamientos específicos y por tanto, cómo será su evolución. Realizando una revisión de datos para un trabajo acerca del carcinoma ductal infiltrante (CDI) me di cuenta que en el informe de anatomía patológica, aparte de informar sobre tamaño, grado histológico, receptores hormonales… siempre al principio, incluía la presencia o no de carcinoma ductal in situ asociado. Me pareció que se trataba de un tema que yo desconocía o al que no le daba mucha importancia. Así, descubrí que sí está muy estudiada su importancia a nivel de márgenes quirúrgicos, así por ejemplo cuándo el componente de carcinoma in situ asociado era extenso, o de alto grado de diferenciación, estas pacientes tenían más recidivas locales y por tanto el tratamiento tenía que ser más agresivo. No encontramos ningún estudio que comparase ni hiciese seguimiento del comportamiento del CDI con componente intraductal (grupo 1) con el CDI sin componente intraductal (grupo2). Por lógica, pensamos como primera hipótesis y principal motivo de la realización de este trabajo que: El carcinoma ductal infiltrante con componente intraductal se comportaría mejor y tendría mejor pronóstico que el carcinoma ductal infiltrante sin componente intraductal porque el primero tendría una evolución más gradual o “por pasos” que el segundo y por lo tanto, tendría una mejor supervivencia total y libre de enfermedad. A partir de ahí, surgió la idea de estudiar y analizar diversas variables epidemiológicas y clínicas, como la afectación ganglionar entre los grupos. Después de esto es cuando nos planteamos ir más allá y ver el comportamiento y la evolución de ambos grupos en un periodo largo de seguimiento para poder estudiar la supervivencia y mortalidad. En cuanto a las características epidiomiológicas y clínicas, no encontramos diferencias significativas entre ambos grupos aunque si existen diferencias en el grado histologico bajo que es más frecuentemente encontrado en las pacientes del grupo 1. Al realizar el seguimiento a 5 años vemos que la presencia de carcinoma intraductal en el carcinoma ductal invasivo tiene una mejor supervivencia libre de enfermedad que el carcinoma ductal invasivo sin carcinoma intraductal (p=0.014) pero no en cuanto a la supervivencia global. En el análisis multivariante, la afectación ganglionar y la presencia de carcinoma intraductal son factores pronósticos independientes. La afectación ganglionar sería un factor de riesgo asociado mientras que en el caso del carcinoma intraductal, cuando está presente, es un factor asociado protector de recidiva. Por tanto, vemos que el carcinoma intraductal en el carcinoma ductal invasivo puede ser factor pronóstico independiente en el cáncer de mama aunque son necesarios estudios prospectivos a largo plazo y con mayor inclusión de pacientes para confirmar tales hipótesis. / As we see in daily practice, neoplasms have very different behaviors. In the era of new prognostic markers continue to seek any information from the patient or tumor that can help us to classify the patient as low or high risk by trying to "predict" how it will respond to specific treatments and therefore how it will evolutionate. Conducting a review of data to work on the infiltrating ductal carcinoma (IDC), I realized that the pathology report, apart from reporting on size, histological grade, hormone receptor ... always at the beginning, incluye the presence or absence of carcinoma associated DCIS. I thought it was a subject I did not attach much importance. So, I discovered that itself is very studied their importance at surgical margins, so for example when the component associated carcinoma in situ was extensive, or high degree of differentiation, these patients had more local recurrences and therefore the treatment had to be more aggressive. We found no studies that compared the behavior or monitor hiciese CDI with intraductal component (group 1) with the CDI without intraductal component (group2). Logically, we think as a first hypothesis and main reason for conducting this work: Infiltrating ductal carcinoma with intraductal component would behave better and have better prognosis than infiltrating ductal carcinoma without intraductal component because the former would have a more gradual evolution or "steps" that the second and therefore would have a better overall survival and freedom of disease. From there, the idea of studying and analyzing different epidemiological and clinical variables, such as lymph node involvement between the groups. After this is when we decided to go further and see the behavior and evolution of both groups over a long period of follow-up to study survival and mortality. As for the characteristics and clinical factors, no significant differences between both groups although there are differences in the histological grade lower than is frequently found in patients in group 1. When monitoring for 5 years we see that the presence of intraductal carcinoma in invasive ductal carcinoma has a better disease-free survival than invasive ductal carcinoma without intraductal carcinoma (p = 0.014) but not in terms of overall survival. In multivariate analysis, lymph node involvement and presence of intraductal carcinoma are independent prognostic factors. Lymph node involvement would be a risk factor while in the case of intraductal carcinoma, when present, is a protective factor associated with relapse. Thus, we see that the intraductal carcinoma in invasive ductal carcinoma may be an independent prognostic factor in breast cancer but prospective studies are needed long term and greater inclusion of patients to confirm these hypotheses.

Intraductal papillary mucinous neoplasms (IPMN) are pancreatic lesions with uncertain biologic behavior. This study sought objective, accurate prediction tools, through the use of quantitative histopathological signatures of nuclear images, for classifying lesions as chronic pancreatitis (CP), IPMN, or pancreatic carcinoma (PC). Forty-four pancreatic resection patients were retrospectively identified for this study (12 CP; 16 IPMN; 16 PC). Regularized multinomial regression quantitatively classified each specimen as CP, IPMN, or PC in an automated, blinded fashion. Classification certainty was determined by subtracting the smallest classification probability from the largest probability (of the three groups). The certainty function varied from 1.0 (perfectly classified) to 0.0 (random). From each lesion, 180 +/- 22 nuclei were imaged. Overall classification accuracy was 89.6% with six unique nuclear features. No CP cases were misclassified, 1/16 IPMN cases were misclassified, and 4/16 PC cases were misclassified. Certainty function was 0.75 +/- 0.16 for correctly classified lesions and 0.47 +/- 0.10 for incorrectly classified lesions (P = 0.0005). Uncertainty was identified in four of the five misclassified lesions. Quantitative histopathology provides a robust, novel method to distinguish among CP, IPMN, and PC with a quantitative measure of uncertainty. This may be useful when there is uncertainty in diagnosis.

Source: Masters Abstracts International, Volume: 48-02, page: . Advisers: Mary E. Edgerton; Michael W. Ross. Includes bibliographical references.

Ces dernières années, il est apparu que le stroma péritumoral et en particulier les fibroblastes associés au cancer exprimant l’actine musculaire lisse (CAFs : carcinoma-associated fibroblasts/ myofibroblasts) faisaient partie intégrante du processus carcinologique observé dans diverses tumeurs épithéliales y compris dans les carcinomes mammaires.L’objectif de ce travail de thèse a donc été :1) D’analyser la distribution « in situ » de ses CAFs/myofibroblastes dans les lésions mammaires de carcinome intraductal (CID), de carcinomes invasifs non spécifiques (No Special Type – CaNST) et de carcinomes métastatiques.2) De déterminer si cette réaction myofibroblastique pouvait prendre naissance à partir des fibroblastes « résidents » CD 34 positifs par l’intermédiaire du TGF-1 et de son récepteur.3) De déterminer si l’action pro carcinogénique de cette réaction myofibroblastique pouvait être liée à la surexpression stromale de la métalloprotéinase de la matrice de type-2 (MMP-2).4) De déterminer si l’expression des récepteurs aux glucocorticoïdes (GR) était présente au sein de ces cellules stromales afin de constituer une cible thérapeutique potentielle. Nos trois premiers travaux ont consisté en une analyse semi-quantitative par immunohistochimie de l’expression de l’anticorps anti- CD 34, marqueur de fibroblastes mammaires, et de l’anticorps anti–actine musculaire lisse (AML), marqueur de myofibroblastes, au sein du stroma de lésions CID, de CaNST et de lésions métastatiques, hépatiques et ganglionnaires. Ces expériences ont mis en évidence la perte progressive de l’expression stromale du CD34 et l’apparition progressive, « en miroir », de l’expression stromale de l’AML autour des foyers de CID et ce de manière proportionnelle au grade nucléaire de ces lésions. En ce qui concerne les CaNST, nous avons constaté la perte de l’expression stromale du CD34 et la présence de la réaction myofibroblastique AML positive dans 100 % des cas. L'intensité d'expression de l'actine musculaire lisse était corrélée de manière significative avec la présence de métastases ganglionnaires. Enfin, cette réaction myofibroblastique a été également retrouvée de manière constante au sein des métastases ganglionnaires et hépatiques. Notre quatrième travail a consisté en l’étude immunohistochimique du TGF-1 et de son récepteur (TGF-R1) dans les lésions de CaNST et au traitement in vitro de lignées cellulaires de fibrocytes mammaires par du TGF-1. Nous avons pu constater une augmentation statistiquement significative de l’expression du TGF-1 au sein des cellules tumorales et une augmentation statistiquement significative de l’expression du TGF-R1 au sein du stroma péritumoral par rapport au tissu mammaire normal. Par ailleurs, le traitement in vitro d’une lignée de fibroblastes mammaires par le TGF-1 faisait apparaître une expression d’AML au sein de ces cellules.Notre cinquième travail a permis de mettre en évidence, par immunohistochimie, une relation entre l’expression stromale de la métalloprotéinase de la matrice de type 2 (MMP-2) et le sous-type tumoral selon la classification luminale. Les tumeurs exprimant HER-2/Neu présentaient une plus forte expression stromale de MMP-2, considérée comme potentiellement pro-invasive.Enfin, notre dernier travail a mis en évidence l’expression fréquente (>90% des cas) des récepteurs aux glucocorticoïdes (GR) au sein des CAFs/ myofibroblastes des CaNST. Cette expression était corrélée de manière significative avec le grade tumoral, l’indice de Ki-67 et l’expression de ces mêmes GR au sein des cellules tumorales épithéliales.En conclusion, les résultats découlant de ces différents travaux démontrent une réaction stromale péritumorale constante et ce tout au long du processus de développement tumoral, dès le stade de carcinome in situ jusqu’au stade métastatique.Une des origines potentielles de ces myofibroblastes est vraisemblablement la transformation des fibroblastes « résidents » mammaires par l’intermédiaire du TGF- et de son récepteur. Ces myofibroblastes présentent par ailleurs des caractéristiques d’expression de MMP-2 différentes en fonction des sous types de carcinomes mammaires suggérant que le stroma péritumoral est en partie différent en fonction du sous type tumoral. Enfin, les récepteurs aux glucocorticoïdes (GR) qui sont fréquemment observés dans ces cellules myofibroblastiques pourraient à l’avenir constituer de nouvelles cibles dans la régulation de l’action de ces cellules. / Doctorat en Sciences médicales (Médecine) / info:eu-repo/semantics/nonPublished

Els tractaments actuals pel càncer de pàncreas presenten un eficàcia limitada de manera que es necessari el desenvolupament de noves teràpies antitumorals. La teràpia gènica pel càncer de pàncreas basada en l’ús d’adenovirus es troba limitada per la baixa capacitat dels virus d’arribar a les masses tumoral, de distribuir-se pel tumor i d’infectar les cèl·lules tumorals. Nosaltres hem observat que l’administració intraductal d’adenovirus al ducte biliar de ratolins Ela-myc permet arribar als tumors pancreàtics de manera més eficient que per la via sistèmica. A més a més permet transduir la majoria de la massa tumoral restringint l’expressió adenoviral al teixit pancreàtic. D’altre banda, l’administració intraductal del tractament AduPARTat8TK/GCV retarda significativament el creixement tumoral i disminueix la toxicitat associada al tumor. El nou adenovirus AdTATMMP és activat per les MMP2/9 restaurant la capacitat de transducció de l’AdYTGRE in vitro, i incrementant 7,3 vegades la infecció del tumor pancreàtic. El tractament combinat de l’AduPARTat8TK/GCV amb gemcitabina presenta un efecte sinèrgic in vitro, però no millora la eficàcia antitumoral de les teràpies simples. D’altre banda el tractament de l’electroporació irreversible presenta efectes antitumorals significatius en tumors ortotòpics de la línia cel·lular BxPC-3-Luc i allarga la supervivència dels ratolins provocant una toxicitat mínima. / Novel therapies are needed to overcome the limited efficacy of current treatments in pancreatic cancer. Adenoviral gene therapy against pancreatic tumors is challenged by the limitation of viruses to reach the tumor mass, poorly distribute within the tumor and inefficiently transduce tumor cells. We show that intraductal administration of adenoviruses into the common bile duct of Ela-myc mice targets pancreatic tumors more efficiently than systemic delivery with relevant transduction of the bulk of the tumor and restricts expression to pancreatic tissue. Moreover, intraductal administration of AduPARTat8TK/GCV treatment significantly delayed tumor growth ameliorating tumor-associated toxicity. Noticeable the new generated MMP-activatable adenovirus AdTATMMP was susceptible to MMP2/9 activation, restored the transduction capacity of AdYTRGE in vitro, and increased 7.3 times tumor pancreas transduction. The multimodal treatment AduPARTat8TK/GCV and gemcitabine showed synergistic effects in vitro; however, did not enhance the antitumoral efficacy of single therapies. Interestingly, IRE treatment exhibited significant antitumor effects in BxPC-3-Luc orthotopic tumors and prolonged mice survival with minimal toxicity.

Orientador: Jose Andres Yunes / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T17:40:29Z (GMT). No. of bitstreams: 1 Silva_AriostoSiqueira_D.pdf: 3970975 bytes, checksum: 7d1f1e04224af1b835486da199d18d00 (MD5) Previous issue date: 2008 / Resumo: Neste trabalho criou-se uma ferramenta de simulação e modelos computacionais para estudo da carcinogênese a fim de se responder a perguntas biológicas pertinentes ao tratamento desta doença. Os modelos computacionais se basearam no modelo teórico de Evolução Somática e Invasão Mediada por Acidez, proposto por Gatenby e Gillies, e foi implementado em uma ferramenta desenvolvida pelo autor deste trabalho no âmbito deste projeto, o Tissue Simulator (TSim, www.i-genics.com). O modelo teórico de invasão mediada por acidez propõe que células tumorais possuem maior resistência a acidez, assim como produzem quantidade de ácido lático, originado da glicólise anaeróbica, suficiente para acidificar o meio extracelular, causando assim morte do tecido saudável por apoptose induzida por acidez, e facilitando a invasão do tecido saudável pelo tumor. Estudos experimentais, na literatura, mostraram que a administração de bicarbonato de sódio na água em ratos portadores de tumores reduz o número de metástases, o que seria uma indicação de que a hipótese sobre a importância da acidez na invasividade tumoral é válida. Neste estudo, criou-se um primeiro modelo computacional para testar se o aumento da concentração de bicarbonato no sangue poderia influenciar no gradiente de acidez entre o tumor (micrometástases) e o tecido saudável, e também identificaram-se as características físico-químicas de um tampão ideal a ser usado com esse propósito. O modelo teórico de Evolução Somática, adotado neste projeto, propõe que para que um tumor epitelial se torne invasivo, é necessário que suas células adquiram três fenótipos: hiperplasia, hiperglicólise e resistência a acidez. O segundo modelo criado neste trabalho consistiu na identificação de quais seriam os valores mínimos de hiperglicólise e resistência à acidez para o aparecimento da característica de invasividade em um tumor em desenvolvimento dentro de um duto epitelial (DCIS). Uma vez identificados os fenótipos mínimos para a invasão tumoral de um DCIS, restaria saber quais as mutações em enzimas ou transportadores específicos dessa via metabólica para que o dito fenótipo seja atingido. A título de exemplo de um estudo para responder perguntas desse tipo, fez-se uma análise comparativa da robustez do fluxo glicolítico em duas células distintas: uma levedura (S. Cerevisiae) e uma célula humana especializada (célula beta pancreática), cujas enzimas principais são reguladas por estratégias distintas. Este estudo foi implementado em uma ferramenta computacional disponível na literatura (Jarnac e Matlab) e resultou na publicação de um artigo. No todo, os resultados desta tese mostram que, com o uso de ferramentas computacionais e dados quantitativos da literatura, é possível criar modelos teóricoquantitativos que podem ser usados para validar teorias sobre fenômenos biológicos assim como extrapolar novas hipóteses e testá-las, integrando-se assim a modelagem computacional no processo de pesquisa científica / Abstract: In this work, we created a piece of software and computer models for studying carcinogenesis, in order to answer biological questions related to the treatment of this disease. The computer models were inspired in the theory of Somatic Evolution and Acid Mediated Tumor Invasion, proposed by Gatenby and Gillies, and were implemented in a tool developed by the author under the scope of this thesis, Tissue Simulator (TSim, www.i-genics.com). The theory of Acid Mediated Tumor Invasion proposes that cancer cells are more resistant to toxicity of an acidic environment that they help create by producing excess of lactic acid through anaerobic glycolysis. Acidification of the extra-cellular environment causes death of healthy tissue through acid-induced apoptosis and ultimately facilitates tumor invasion. Experimental studies, from literature, showed that administration of sodium bicarbonate in water to mice bearing tumors reduced the number of metastases, thus supporting the importance of acidity in tumor invasion. In this study a computer model was built to test if an increase in concentration of bicarbonate in blood serum could alter the pH gradient between the tumor (micrometastases) and halthy tissue, as well as to identify the chemical properties of and ideal buffer with this purpose. The theory of Somatic Evolution, proposes that epithelial tumor cells are submitted to environmental barriers and are selected for three main phenotypes: hyperplasia, hyperglycolysis and acid resistance. A second computer model was created in order to identify the minimum values of these phenotypes that allowed a DCIS to change into an invasive tumor. Once the minimum phenotypic values identified, one can study how mutations on specific enzymes can alter the flux of a metabolic pathway, such as glycolysis, to produce the altered phenotype. As an example of this, we performed a comparative study of robustness of glycolytic flux in two different cells: yeast (S. cerevisiae) and pancreatic human beta-cell, whose enzymatic regulatory strategies differ. This computer model was implemented on Matlab and Jarnac. Overall, our results show that the use of computational tools and quantitative data may be used to create theoretical-quantitative models that help adressing theories about biological systems, as well as to extrapolate and tes new hypothesis, integrating the approach of computational modeling in the scientific research process / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular

BACKGROUND: Pancreatic cancer is one of the most lethal cancers. Despite enhanced understanding of the disease, the 5-year survival rate remains 8% due to the late stage of diagnosis and a lack of effective treatment options. Early detection of precancerous lesions, such as intraductal papillary mucinous neoplasms (IPMNs), is a strategy to prevent pancreas cancer related death. Standard qualitative imaging assessment cannot reliably distinguish between benign and malignant branch duct intraductal papillary mucinous neoplasms (BD-IPMNs). A more consistent risk prediction method is needed to inform clinical decision making such that patients with benign cysts may be spared from unnecessary surgical resection. OBJECTIVE: To assess whether a BD-IPMN malignancy risk prediction model which demonstrated strong potential on preoperative computed tomography (CT) images would show similar results on magnetic resonance imaging (MRI). METHODS: 19 pathologically proven BD-IPMN patients with preoperative contrast-enhanced CT and MRI and were included in the study. Five radiomics features were extracted from the portal-venous phase CT and MR images of the largest cyst. Associations between radiomics features extracted from CT and MR were assessed using Pearson correlations. RESULTS: Of the five radiomics features, average-weighted eccentricity (AWE) was most strongly correlated between imaging modalities in all patients (n=19, r=0.46, 95% CI=0.001-0.75, p=0.05), low-risk patients (r=0.63, 95% CI=0.09-0.88, p=0.028), and patients with a solid component or mural nodule (r=0.66, 95% CI=-0.32-0.96, p=0.15). However, when two outliers within the dataset were removed from analysis, AWE no longer correlated between MR and CT. None of the other radiomics features displayed significant correlations between the modalities. CONCLUSIONS: The CT-based risk prediction model cannot be applied to MR data suggesting that a new model should be created from MRI data alone. / 2021-06-17T00:00:00Z

Ductal carcinoma in situ (DCIS); is thought directly to precede invasive breast cancer (IBC). Screening mammography has driven the incidence of this key precursor lesion to >65,000 cases per year. However, little is known about the factors controlling the natural history or risk for recurrence following treatment of a particular patients DCIS. Though the heterogeneity of the disease is well established, no histologic or demographic criteria have been able to stratify DCIS for treatment. We hypothesize that at initial diagnosis there exist biologically distinct subsets of DCIS with associated prognoses that may be recognized by molecular markers. Molecular approaches have been limited by technical design issues related to the types of tissue available for analysis, namely degraded formalin-fixed paraffin embedded (FFPE) specimens and small core biopsy samples. However, new technologies promise to overcome these issues. In the first phase of our investigation, we aimed a) to pilot feasibility studies on the use of FFPE DCIS for molecular analyses including gene expression microarray and b) to pilot feasibility study of selective, high throughput sequencing through the use of "exon capture" on small input material that simulated expected DCIS core biopsy amounts. The results of this work offer specific technical guidelines for the molecular study of DCIS. Moreover, they have enabled the initiation of the second phase of this study, which aims to assess molecular profiles of DCIS recurrence and progression.

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Têm sido propostos vários sistemas de classificação de carcinoma ductal in situ de mama (CDIS). Essa classificação necessita ter significado clínico, auxiliando a melhor compreensão da doença, a escolha terapêutica e definição de prognóstico. Poucos estudos avaliaram o grau de concordância entre diferentes sistemas de classificação. Este estudo tem como objetivo determinar o grau de concordância diagnóstica de patologistas entre três sistemas de classificação do CDIS. Dois patologistas revisaram 43 casos, com diagnóstico de CDIS, selecionados para análise interobservador. Treze patologistas receberam o mesmo conjunto de imagens digitalizadas da microscopia, em formato JPG, dos casos de CDIS e responderam um questionário contendo os critérios para composição dos três sistemas de classificação estudados − Holland, Lagios modificado e Van Nuys. Para tal fim, foi criado um programa informatizado que, ao final, organiza as informações coletadas de cada um dos patologistas avaliadores, fornecendo a graduação histológica dos casos para os três sistemas de classificação. Os resultados foram analisados, usando-se concordância percentual e teste de Kappa. A concordância diagnóstica para os três sistemas de classificação de CDIS de mama foi considerada aceitável, com valores de Kappa que variaram de 0,27 a 0,37. Entre as três classificações estudadas, houve melhor concordância para a de Van Nuys, mostrando índice de Kappa de 0,37. A análise de subgrupos de patologistas, distintos por seu interesse em patologia mamária, mostrou haver maior reprodutibilidade do diagnóstico para o grupo de especialistas em relação ao de residentes em patologia para os sistemas de Van Nuys e Lagios modificado (p=0,005 e 0,023, respectivamente). A acurácia de forma semelhante acompanhou os resultados das concordâncias interobservador, tendo como achados índices de Kappa, variando de 0,13 a 0,64 para classificação de Holland; 0,23 a 0,61 para a classificação de Lagios modificada; e de 0,23 a 0,74 para a classificação de Van Nuys. Comparando os três sistemas de classificação, obteve-se melhor concordância para o grau histológico com o esquema de Van Nuys. Patologistas especialistas em patologia mamária mostraram maior reprodutibilidade para todos os critérios avaliados em relação aos patologistas em geral não dedicados a essa especialidade. A acurácia diagnóstica foi superior para a classificação de Van Nuys, em relação à de Lagios modificada e à de Holland.