935 resultados para Ovarian Cancer


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One common characteristic of breast cancers arising in carriers of the predisposition gene BRCA1 is a loss of expression of the CDK inhibitor p27(Kip1) (p27), suggesting that p27 interacts epistatically with BRCA1. To investigate this relationship, we examined expression of p27 in mice expressing a dominant negative allele of Brca1 (MMTV-trBr) in the mammary gland. While these mice rarely develop tumors, they showed a 50% increase in p27 protein and a delay in mammary gland development associated with reduced proliferation. In contrast, on a p27 heterozygote background, MMTV-trBrca1 mice showed an increase in S phase cells, and normal mammary development. p27 was the only protein in the cyclin cyclin-dependent kinase network to show altered expression, suggesting that it may be a central mediator of cell cycle arrest in response to loss of function of BRCA1. Furthermore, in human mammary epithelial MCF7 cells expressing BRCA1-specific RNAi and in the BRCA1-deficient human tumor cell line HCC1937, p27 is elevated at the mRNA level compared to cells expressing wild-type BRCA1. We hypothesize that disruption of BRCA1 induces an increase in p27 that inhibits proliferation. Accordingly, reduction in p27 expression leads to enhancement of cellular proliferation in the absence of BRCA1.

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Cross-species comparative genomics is a powerful strategy for identifying functional regulatory elements within noncoding DNA. In this paper, comparative analysis of human and mouse intronic sequences in the breast cancer susceptibility gene (BRCA1) revealed two evolutionarily conserved noncoding sequences (CNS) in intron 2, 5 kb downstream of the core BRCA1 promoter. The functionality of these elements was examined using homologous-recombination-based mutagenesis of reporter gene-tagged cosmids incorporating these regions and flanking sequences from the BRCA1 locus. This showed that CNS-1 and CNS-2 have differential transcriptional regulatory activity in epithelial cell lines. Mutation of CNS-1 significantly reduced reporter gene expression to 30% of control levels. Conversely mutation of CNS-2 increased expression to 200% of control levels. Regulation is at the level of transcription and shows promoter specificity. Both elements also specifically bind nuclear proteins in vitro. These studies demonstrate that the combination of comparative genomics and functional analysis is a successful strategy to identify novel regulatory elements and provide the first direct evidence that conserved noncoding sequences in BRCA1 regulate gene expression. (c) 2005 Elsevier Inc. All rights reserved.

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Endometriosis is a common gynaecological disease with symptoms of pelvic pain and infertility which affects 7-10% of women in their reproductive years. Activation of an oncogenic allele of Kirsten rat sarcoma viral oncogene homologue (KRAS) in the reproductive tract of mice resulted in the development of endometriosis. We hypothesized that variation in KRAS may influence risk of endometriosis in humans. Thirty tagSNPs spanning a region of 60.7 kb across the KRAS locus were genotyped using iPLEX chemistry on a MALDI-TOF MassARRAY platform in 959 endometriosis cases and 959 unrelated controls, and data were analysed for association with endometriosis. Genotypes were obtained for most individuals with a mean completion rate of 99.1%. We identified six haplotype blocks across the KRAS locus in our sample. There were no significant differences between cases and controls in the frequencies of individual single-nucleotide polymorphisms (SNPs) or haplotypes. We also developed a rapid method to screen for 11 common KRAS and BRAF mutations on the Sequenom MassARRAY system. The assay detected all mutations previously identified by direct sequencing in a panel of positive controls. No germline variants for KRAS or BRAF were detected. Our results demonstrate that any risk of endometriosis in women because of common variation in KRAS must be very small.

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The overall objective of the research presented in this dissertation was to assess exposure to endocrine disrupting chemicals (EDCs), polychlorinated biphenyls (PCBs), phthalates, and bisphenol A (BPA) in the general population and evaluate their associations with adverse reproductive health effects, including cancers, in women. Given the proven contribution of unopposed estrogens to the risk for endometrial neoplasia or breast cancer, renewed health concerns have aroused about estrogen mimicking EDCs found in food, personal care products or as environmental contaminants. Our meta-analysis showed that exposure to estrogen mimicking PCBs increased summary risk of breast cancer and endometriosis. We further evaluated the relationship between endometriosis and breast cancer, and EDCs using a bioinformatics method. Our bioinformatics approach was able to identify genes with the potential to be involved in interaction with PCB, phthalates and BPA that may be important to the development of breast cancer and endometriosis. Therefore, we hypothesized that exposure to EDCs such as PCBs, phthalates, and BPA, results in adverse reproductive health effects in women. Using subject data and biomarkers available from the Center for Disease Controls National Health and Nutrition Examination Survey database we conducted a cross-sectional study of EDCs in relation to self-reported history of endometriosis, uterine leiomyomas, breast cancer, cervical cancer, ovarian cancer, and uterine cancer. Significantly higher body burdens of PCBs were found in women diagnosed with breast cancer, ovarian cancer, and uterine cancer compared to women without cancer. PCB 138 was significantly associated with breast cancer, cervical cancer, and uterine cancer, while PCBs 74 and 118 were significantly associated with ovarian cancer. The sum of dioxin-like PCBs were significantly associated with ovarian cancer (OR of 2.02, 95% CI: 1.06-3.85) and the sum of non-dioxin-like PCBs were significantly associated with uterine cancer (OR of 1.12, 95%CI: 1.03-1.23). Significantly higher body burdens of PCBs were also found in women diagnosed with endometriosis and uterine leiomyomas. Documenting the exposure to EDCs among the general U.S. population, and identifying agents associated with reproductive toxicity have the potential to fill research gaps and facilitate our understanding of the complex role environmental chemicals play in producing toxicity in reproductive organs.^

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The overall objective of the research presented in this dissertation was to assess exposure to endocrine disrupting chemicals (EDCs), polychlorinated biphenyls (PCBs), phthalates, and bisphenol A (BPA) in the general population and evaluate their associations with adverse reproductive health effects, including cancers, in women. Given the proven contribution of unopposed estrogens to the risk for endometrial neoplasia or breast cancer, renewed health concerns have aroused about estrogen mimicking EDCs found in food, personal care products or as environmental contaminants. Our meta-analysis showed that exposure to estrogen mimicking PCBs increased summary risk of breast cancer and endometriosis. We further evaluated the relationship between endometriosis and breast cancer, and EDCs using a bioinformatics method. Our bioinformatics approach was able to identify genes with the potential to be involved in interaction with PCB, phthalates and BPA that may be important to the development of breast cancer and endometriosis. Therefore, we hypothesized that exposure to EDCs such as PCBs, phthalates, and BPA, results in adverse reproductive health effects in women. Using subject data and biomarkers available from the Center for Disease Controls National Health and Nutrition Examination Survey database we conducted a cross-sectional study of EDCs in relation to self-reported history of endometriosis, uterine leiomyomas, breast cancer, cervical cancer, ovarian cancer, and uterine cancer. Significantly higher body burdens of PCBs were found in women diagnosed with breast cancer, ovarian cancer, and uterine cancer compared to women without cancer. PCB 138 was significantly associated with breast cancer, cervical cancer, and uterine cancer, while PCBs 74 and 118 were significantly associated with ovarian cancer. The sum of dioxin-like PCBs were significantly associated with ovarian cancer (OR of 2.02, 95% CI: 1.06-3.85) and the sum of non-dioxin-like PCBs were significantly associated with uterine cancer (OR of 1.12, 95%CI: 1.03-1.23). Significantly higher body burdens of PCBs were also found in women diagnosed with endometriosis and uterine leiomyomas. Documenting the exposure to EDCs among the general U.S. population, and identifying agents associated with reproductive toxicity have the potential to fill research gaps and facilitate our understanding of the complex role environmental chemicals play in producing toxicity in reproductive organs.

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Purpose: To qualitatively explore the communication between healthcare professionals and oncology patients based on the perception of patients undergoing chemotherapy.Method: Qualitative and exploratory design. Participants were 14 adult patients undergoing chemotherapy at different stages of the disease. A socio-demographic and clinical data form was utilized along with semi-structured interviews. The interviews were audio-recorded, transcribed and content analysis was performed. Two independent judges evaluated the interview content in regards to emerging categories and obtained a Kappa index of 0.834.Results: Three categories emerged from the data: 1) Technical communication without emotional support, in which the information provided is composed of strictly technical information regarding the diagnosis, treatment and/or prognosis; 2) Technical communication, in which the information provided is oriented towards the technical aspects of the patient’s physical condition, while also providing psychological support for the patients’ subjective needs; and 3) Insufficient technical communication, win which there are gaps in the information provided causing confusion and suffering to the patient.Conclusions: Communication with emotional support contributes to greater satisfaction of chemotherapy patients. Practical implications: the results provide elements for the training of healthcare professionals regarding the importance of the emotional support that can be offered to cancer patients during their treatment.

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Au Canada, en 2015, il était estimé que 78 000 personnes allaient mourir d’un cancer, représentant 30 % de tous les décès et faisant de celui-ci la première cause de mortalité. De plus, 196 900 nouveaux cas de cancers seraient découverts au cours de cette même année (Canadian Cancer Society’s Advisory Committee on Cancer Statistics. Canadian Cancer Statistics 2015. Toronto, ON : Canadian Cancer Society; 2015). L’intégrité du génome est chaque jour menacée par des conditions environnementales qui endommagent l’ADN (ultraviolets, produits chimiques divers, etc.). Parmi les différents types de lésions, l’un des plus délétères et pouvant mener au cancer est la cassure double-brin (CDB). Celle-ci peut être réparée suivant deux mécanismes majeurs : la jonction des extrémités non homologues (Non-Homologous End-Joining ou NHEJ) ou la Recombinaison Homologue (RH). Cette dernière, prépondérante pendant les phases S/G2, consiste en la réparation d’une CDB grâce à l’utilisation d’une chromatide soeur comme modèle, permettant une réparation fidèle du dommage. La RH est sous la dépendance de diverses protéines, dont RAD51, PALB2 et BRCA2. Ces deux dernières sont connues pour être mutées dans les cancers du sein et des ovaires. Ainsi, la compréhension de l’implication de chaque acteur dans la RH est un objectif fondamental dans la lutte contre le cancer et constitue l’objectif général de cette thèse. En 2012, une étude a montré qu’une nouvelle protéine, APRIN (Androgen-induced PRoliferation INhibitor), appartenant au complexe cohésine, interagissait avec BRCA2 et jouait un rôle dans la RH. Les rôles précis d’APRIN dans ce mécanisme restaient toutefois à être définis. Le projet principal de cette thèse repose sur la caractérisation fonctionnelle d’APRIN dans la réparation par RH. Nous révélons qu’APRIN aurait un rôle spécifique et indépendant de celui de la cohésine dans la RH, et pourrait agir à diverses étapes cruciales de ce mécanisme. De plus, nos données montrent que le niveau d’expression d’APRIN pourrait être un marqueur de prédiction dans le cancer ovarien. Étant donné qu’APRIN interagit aussi avec PALB2, autre partenaire essentiel de BRCA2, nous avons également étudié et caractérisé les fonctions de divers mutants de PALB2. Nous faisons ainsi la découverte inattendue d’un nouveau phénotype induit par une troncation de cette protéine associée à certains cancers agressifs. Ainsi, cette thèse apporte des informations supplémentaires et indispensables à la compréhension de la réparation de l’ADN par RH et de la survenue de certains cancers.

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This thesis attempts to provide deeper historical and theoretical grounding for sense-making, thereby illustrating its applicability to practical information seeking research. In Chapter One I trace the philosophical origins of Brenda Dervin’s theory known as “sense making,” reaching beyond current scholarship that locates the origins of sense-making in twentieth-century Phenomenology and Communication theory and find its rich ontological, epistemological, and etymological heritage that dates back to the Pre-Socratics. After exploring sense-making’s Greek roots, I examine sense-making’s philosophical undercurrents found in Hegel’s Phenomenology of Spirit (1807), where he also returns to the simplicity of the Greeks for his concept of sense. With Chapter Two I explore sense-making methodology and find, in light of the Greek and Hegelian dialectic, a dialogical bridge connecting sense-making’s theory with pragmatic uses. This bridge between Dervin’s situation and use occupies a distinct position in sense-making theory. Moreover, building upon Brenda Dervin’s model of sense-making, I use her metaphors of gap and bridge analogy to discuss the dialectic and dialogic components of sense making. The purpose of Chapter Three is pragmatic – to gain insight into the online information-seeking needs, experiences, and motivation of first-degree relatives (FDRs) of breast cancer survivors through the lens of sense-making. This research analyses four questions: 1) information-seeking behavior among FDRs of cancer survivors compared to survivors and to undiagnosed, non-related online cancer information seekers in the general population, 2) types of and places where information is sought, 3) barriers or gaps and satisfaction rates FDRs face in their cancer information quest, and 4) types and degrees of cancer information and resources FDRs want and use in their information search for themselves and other family members. An online survey instrument designed to investigate these questions was developed and pilot tested. Via an email communication, the Susan Love Breast Cancer Research Foundation distributed 322,000 invitations to its membership to complete the survey, and from March 24th to April 5th 10,692 women agreed to take the survey with 8,804 volunteers actually completing survey responses. Of the 8,804 surveys, 95% of FDRs have searched for cancer information online, and 84% of FDRs use the Internet as a sense-making tool for additional information they have received from doctors or nurses. FDRs report needing much more information than either survivors or family/friends in ten out of fifteen categories related to breast and ovarian cancer. When searching for cancer information online, FDRs also rank highest in several of sense-making’s emotional levels: uncertainty, confusion, frustration, doubt, and disappointment than do either survivors or friends and family. The sense-making process has existed in theory and praxis since the early Greeks. In applying sense–making’s theory to a contemporary problem, the survey reveals unaddressed situations and gaps of FDRs’ information search process. FDRs are a highly motivated group of online information seekers whose needs are largely unaddressed as a result of gaps in available online information targeted to address their specific needs. Since FDRs represent a quarter of the population, further research addressing their specific online information needs and experiences is necessary.

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A atividade antiproliferativa in vitro de uma série de amidas graxas sintéticas, em sete linhagens de células tumorais foi investigada. Baseado em GI50, TGI e LC50, os ensaios preliminares mostraram que a maior parte dos compostos mostrou atividade antiproliferativa moderada a boa contra as linhagem de células tumorais testadas, principalmente em células de glioma humano (U251) e câncer de ovário humano com fenótipo de resistentencia a múltiplos fármacos (NCI-ADR/RES). A amida (R,S)-3d, derivada do ácido ricinoleico, mostrou uma elevada seletividade com potência de inibição do crescimento e morte celular para a linhagem de células de glioma. Além disso, as amidas (S)-3c e (S)-3e, derivadas dos ácidos oleico e linoleico respectivamente, foram especificas para glioma e ovário com fenótipo de resistência a múltiplos fármacos com inibição potente do crescimento celular. Estes resultados aliados a um perfil de segurança relativo quando analisado o efeito sobre as linhagens celulares não–tumorais, apontam para que estes compostos sirvam como modelos para o desenvolvimento de candidatos a fármacos para o tratamento de câncer, incluindo cânceres com fenótipo de resistência a múltiplos fármacos.

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Hereditary syndromes are responsible for 10 % of gynaecologic cancers, among which hereditary breastovarian cancer and hereditary non-polyposis colon cancer syndromes, known as HBOC and Lynch syndromes respectively, present the highest relative risk. The latter predisposes to endometrial cancer and both contribute to ovarian cancer. Cowden syndrome-related endometrial cancer and the increased risk of ovarian, uterine and cervical cancers associated with Peutz-Jeghers syndrome, are also demonstrated, while Li-Fraumeni syndrome patients are prone to develop ovarian and endometrial cancers. Despite these syndromes’ susceptibility to gynaecologic cancers being consensual, it is still not clear whether these tumours have any epidemiologic, clinical, pathologic or imaging specific features that could allow any of the intervening physicians to raise suspicion of a hereditary syndrome in patients without known genetic risk. Moreover, controversy exists regarding both screening and surveillance schemes. Our literature review provides an updated perspective on the evidence-based specific features of tumours related to each of these syndromes as well as on the most accepted screening and surveillance guidelines. In addition, some illustrative cases are presented.

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Objectives To review the epidemiological and clinical features of primary fallopian tube carcinoma (PFTC), and to illustrate the spectrum of MRI findings, with pathological confirmation. Methods This article reviews the relevant literature on the epidemiological, clinical, and imaging features of primary fallopian tube carcinoma, with pathological confirmation, using illustrations from the authors’ teaching files. Results Primary fallopian tube carcinoma came under focus over the last few years due to its possible role on the pathogenesis of high-grade serous epithelial ovarian and peritoneal cancers. Typical symptoms, together with the presence of some of the most characteristic MRI signs, such as a Bsausage-shaped^ pelvic mass, hydrosalpinx, and hydrometra, may signal the presence of primary fallopian cancer, and allow the radiologist to report it as a differential diagnosis. Conclusions Primary fallopian tube carcinoma has a constellation of clinical symptoms and magnetic resonance imaging features, which may be diagnostic. Although these findings are not present together in the majority of cases, radiologists who are aware of them may include the diagnosis of primary fallopian tube cancer in their report more frequently and with more confidence. Teaching Points • PFTC may be more frequent than previously thought • PFTC has specific clinical and MRI characteristics • Knowledge of typical PFTC signs enables its inclusion in the differential diagnosis • PFTC is currently staged under the 2013 FIGO system • PFTC is staged collectively with ovarian and peritoneal neoplasms

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O carcinoma do ovário é na maioria das vezes diagnosticado num estádio avançado. Nos últimos anos a quimioterapia neoadjuvante tem emergido como uma terapêutica alternativa para os casos de doença avançada em que não é possível uma adequada remoção cirúrgica dos implantes tumorais, sendo a cirurgia cito-redutora adiada para uma segunda fase. A Radiologia tem vindo a assumir um papel importante na selecção destas doentes, com definição de critérios de irressecabilidade avaliados por Tomografia Computorizada e que se relacionam sobretudo com a localização e dimensão dos implantes.

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O esclarecimento do órgão de origem, ou principalmente da natureza benigna ou maligna de um tumor anexial ecograficamente indeterminado surge com frequência na prática clínica e obriga a uma investigação complementar da sua natureza de modo a evitar cirurgias inúteis, sem deixar de diagnosticar precocemente a patologia maligna. Neste trabalho apresentamos um algoritmo de diagnóstico por Ressonância Magnética (RM), que recentemente foi proposto pela European Society of Urogenital Radiology (ESUR), o qual permite um diagnóstico preciso dos casos indeterminados à ecografia e uma intervenção responsável na abordagem clínica destas doentes.

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Dissertação de Mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologias, Universidade do Algarve, 2014