O acometimento por uma doença crônica como o câncer se constitui em uma ameaça à vida e tem repercussões físicas, psicológicas e sociais no decorrer da existência. No caso do câncer de próstata, sabe-se que seus tratamentos podem interferir na sexualidade masculina, causando perda do desejo sexual e disfunção erétil. Considerando esta realidade, o objetivo deste trabalho foi compreender o modo como homens com câncer de próstata vivenciam e atribuem significados à sua sexualidade. Optou-se pela metodologia da pesquisa qualitativa, na perspectiva da Fenomenologia Ontológico-Hermenêutica de Heidegger. E utilizou-se a história oral de vida como estratégia de acesso aos relatos dos colaboradores. Foram entrevistados 10 homens com câncer de próstata que foram submetidos a tratamentos, com idades entre 51 e 82 anos, pertencentes às classes econômicas D a B2. Os resultados dos relatos possibilitaram a construção de cinco categorias: 1) A temporalidade da infância e da adolescência; 2) A temporalidade da vida adulta: o casamento, a família e os relacionamentos afetivo-sexuais; 3) O adoecimento: as relações afetivo-sexuais após a vivência do câncer; 4) O horizonte do silêncio: o que vela e desvela o ser; e 5) Projeto de vida. A análise interpretativa desvelou a dor e o sofrimento desses homens ao apresentarem disfunção erétil e seqüelas no seu desempenho sexual, atributo do ideal de masculinidade advindo do sistema patriarcal. As vivências de dor remetem-se aos modos de existir autêntico e inautêntico. A inautenticidade foi observada na recusa em aceitar a facticidade da existência, ou seja, a concretude de um corpo que envelhece, adoece e deixa de responder ao desejo sexual. O acometimento pelo câncer de próstata potencializa o contato com a própria finitude, e alguns colaboradores fogem à angústia que surge quando se constata a possibilidade última e mais própria do existir: a morte. Esses homens buscam, então, os tratamentos disponíveis para a disfunção erétil e projetam seu porvir na possibilidade de voltarem a ter ereções satisfatórias, o que expressa o sonho do desempenho sexual vivido na juventude. Todavia, nessa trajetória, alguns colaboradores apresentaram um modo de existir autêntico, evidenciado pela compreensão da temporalidade de sua existência. Seus relatos desvelaram a consciência de que, por não poderem escapar à finitude, lhes resta aceitar as modificações na sexualidade e buscar vivenciá-la de acordo com seus limites e possibilidades. O modo de existir autêntico, que constitui a abertura do homem para o poder-ser-si-mesmo, foi desvelado na afetividade e no diálogo dos colaboradores com suas parceiras. Nesse momento em que os homens perdem a capacidade de ter ereções e sentem-se frágeis em sua masculinidade, se permitem expressar um aspecto fundamental da existência: a afetividade. A abertura para falar sobre si mesmo e ouvir sua parceira evidencia a dimensão do cuidado e da solicitude na relação afetivo-sexual. Os resultados deste estudo apontam para a compreensão ontológica do ser do homem com câncer de próstata na Pós-Modernidade e podem contribuir na construção de práticas de atenção à saúde mais humanizadas. / The effect for a chronic illness as cancer constitutes in a threat the life and has physical, psychological and social repercussions in elapsing of the existence. In the case of cancer of prostate, it is known that its treatment can intervene with the masculinity sexuality, causing loss of the sexual desire and erect dysfunction. Considering this reality, the objective of this work was to understand the way as men with cancer of prostate live deeply and attribute meanings to their sexuality. It was opted to the methodology of the qualitative research, in the perspective of the Martin Heidegger?s Ontological ? Hermeneutical Phenomenology. It was used verbal story of life as strategy of access to the stories of the collaborators. Ten men with cancer of prostate had been interviewed who had been submitted the treatments, with ages between 51 and 82 years, pertaining to economic classes D to B2. The results of the stories make possible the construction of five categories: 1) the temporality of infancy and the adolescence; 2) the temporality of the adult life: the affective marriage, family and sexual relationships; 3) the sickness: sexual affective relations after the experience of cancer; 4) the horizon of silence: what close and disclose the being; 5) life project. The interpretative analyzes exposed the pain and the suffering of these men when presenting erect dysfunction and aftermaths in their sexual performance, attribute of the ideal of masculinity happened of the patriarchal system. The pain experiences send the ways to it to exist authentic and fake. The fake way was observed in the refusal in accepting the fact of the existence, or either the acceptance of a body that ages, sickens and leaves to answer to the sexual desire. The effect for cancer of prostate elevates the contact with the proper end and some collaborators runs away to distresses that it appears when the last possibility is evidenced and more proper to exist: the death. These men search then, the available treatments for the erect dysfunction and project their future in the possibility to come back to have satisfactory erections, what express the dream of the lived sexual performance in youth. However, in this trajectory, some collaborators presents a way to exist authentic, evidenced for the understanding of the temporality of their existence. Their relates disclosed the conscience of that, for not being able to escape to the end, it remains to accept the modifications to them in the sexuality and in accordance with to live deeply their limits and possibilities. The way to exist authentic, that it constitutes the opening of the man to be able to be same itself, was disclosed in the affectivity and the dialogue of the collaborators with their partners. At this moment when the men lose the capacity to have erections and feel themselves fragile in their masculinity, if they allow expressing a basic aspect of the existence: the affectivity. The opening to speak about himself exactly and to hear his partner evidences the dimension of the care and the attention in the affective-sexual relation. The results of this study point with respect to the ontological understanding of the being of the man with cancer of prostate in Post-modernity and can contribute in the construction of practical of attention to health more humanized.

O objetivo deste estudo foi o de medir in vivo as dimensões da próstata, pelo exame ultra-sonográfico, de cães de diferentes tamanhos, com idade entre 1 e 5 anos. Foram realizados exames em 47 cães, sem processos patológicos aparentes. Os pacientes foram divididos em dois grupos de acordo com a idade, Grupo 1: cães entre 12 e 30 meses e Grupo 2: cães entre 31 e 60 meses. Cada grupo foi subdividido em três subgrupos de acordo com o peso. Subgrupos 1 e 4 com animais até 10kg, Subgrupos 2 e 5 com animais entre 11 e 25kg e Subgrupos 3 e 6 com animais acima de 25kg sendo que os Subgrupos 1 a 3 pertencem ao Grupo 1 e os Subgrupos 4 a 6 pertencem ao Grupo 2. As imagens em corte longitudinal e transversal permitiram a observação da próstata, localizada caudalmente à bexiga urinária, de formato arredondado, de contornos regulares e definidos e de ecogenicidade maior que a do baço. Comprimento e altura foram mensurados no plano longitudinal, já a largura foi medida no plano transversal. O Subgrupo 1 apresentou medidas prostáticas de comprimento: 1,19 (±0,16cm); de altura: 1,17 (±0,2cm) e de largura: 1,41 (±0,24cm), valores menores que os obtidos no Subgrupo 4 que apresentou comprimento: 2,14 (±0,13cm); altura: 2,12 (±0,16cm) e largura de 2,59 (±0,21cm). O Subgrupo 2 apresentou valores prostáticos de comprimento: 2,17 (±0,11cm); de altura: 2,04 (±0,15cm) e de largura: 2,64 (±0,13cm), valores menores que os obtidos no Subgrupo 5 que apresentou comprimento: 2,81 (±0,44cm); altura 3,73: (±0,37cm) e largura de 3,29 (±0,38cm). O Subgrupo 3 apresentou valores prostáticos de comprimento 3,09 (±0,21cm); de altura: 2,93 (±0,21cm) e de largura: 3,63 (±0,19cm), valores menores que os obtidos no Subgrupo 6 que apresentou comprimento: 3,47 (±0,31cm); altura: 3,35 (±0,35cm) e largura de 4,03 (±0,28cm). A correlação foi forte entre os valores prostáticos determinados e a massa corpórea dos cães estudados. / The aim of this study was ultrasonographically assess the prostatic dimensions in dogs of different sizes, aging from 1 to 5 years-old. Forty-seven examinations were done, in dogs with no clinical diseases. The patients were divided into two groups according to their ages, such as: Group 1 - from 12 to 30 months-old and Group 2 ? from 31 to 60 months-old. Each group was divided into 3 other groups according to their weight. Subgroup 1 and 4: up to 10 Kg, subgroup 2 and 5: from 11 to 25 Kg and subgroups 3 and 6: over 25 Kg (subgroups 1 to 3 were inserted in Group 1 and subgroups 4 to 6 were inserted in Group 2). The sagittal and transverse planes on ultrasonographic examination provided the entire visualization of the prostate, which was round to normal-shaped, lies caudally to the urinary bladder, with smooth margins and hyperechoic to the spleen. Their length and height were measured on sagittal plane and the width was measured on transverse plane. Regarding the subgroup 1, the mean prostatic length was 1,19 cm (± 0,16 cm), the mean prostatic height was 1,17 cm (± 0,2 cm) and the mean prostatic width was 1,41 cm (± 0,24 cm), and these measurements showed to be shorter than the ones from subgroup 4, such as 2,14 cm (± 0,13) as for the mean length, 2,12 cm (± 0,16 cm) as for the mean height and finally 2,59 cm (± 0,21 cm) as for the mean width. Regarding the subgroup 2, the mean prostatic length was 2,17 cm (± 0,11), the mean height was 2,04 (± 0,15 cm) and the mean width was 2,64 cm (± 0,13), and these measurements showed to be shorter than the ones from subgroup 5, such as 2,81 cm (± 0,44) as for mean length, 3,73 cm (± 0,37 cm) as for the mean height and finally 3,29 cm (± 0,38 cm) as for the mean width. Regarding the subgroup 3, the mean prostatic length was 3,09 cm (± 0,21), the mean height was 2,93 (± 0,21 cm) and the mean width was 3,63 cm (± 0,19), and these measurements showed to be shorter than the ones from subgroup 6, such as 3,47 cm (± 0,31) as for mean length, 3,35 cm (± 0,35 cm) as for the mean height and finally 4,03 cm (± 0,28 cm) as for the mean width. There was a high correlation between the prostatic dimensions and the body mass of theses dogs.

Orientador: Valéria Helena Alves Cagnon Quitete / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T04:47:08Z (GMT). No. of bitstreams: 1 Kido_LarissaAkemi_M.pdf: 14026607 bytes, checksum: 4b5dcdcd04b3cf312f7b62cb4cf2ac2b (MD5) Previous issue date: 2013 / Resumo: A senescência está associada a mudanças significativas no ambiente hormonal, sendo fator causador de alterações morfofuncionais na próstata. Os diferentes processos biológicos que ocorrem na próstata são regulados por polipeptídeos, dentre esses os fatores de crescimento do endotélio vascular (VEGF) e Endostatina, relacionados à angiogênese. Além disso, inibidores da enzima 5_ redutase-II, como a finasterida, tem papel importante no combate às doenças prostáticas. Assim, os principais objetivos desse estudo foram avaliar os efeitos estruturais e moleculares das terapias antiangiogênicas e da finasterida sobre a próstata ventral de camundongos durante a senescência. Noventa camundongos machos FVB de 18 e 52 semanas de idade foram divididos nos seguintes grupos: Jovem (JV) e Senil (SEN), os quais receberam injeções de Solução Fisiológica 0,9% (5 mL/Kg/dia s.c.); Finasterida (FIN): injeções de Finasterida (20 mg/Kg, s.c.); SU5416 (SU): SU5416 (6 mg/Kg, i.p.); TNP-470 (TNP): injeções de TNP-470 (15 mg/Kg, s.c.), e SU5416 + TNP-470 (SU+TNP): os mesmos tratamentos dos grupos SU e TNP. Após 21 dias de tratamento, amostras do lobo ventral da próstata foram coletadas e submetidas às análises morfológicas, imunohistoquímicas e Western Blotting. Os resultados demonstraram alterações moleculares e estruturais no microambiente prostático durante a senescência, como atrofia presença de células inflamatórias, e lesões proliferativas, as quais foram interrompidas e ou bloqueadas através dos tratamentos com as drogas antiangiogênicas e pela finasterida. Os resultados moleculares revelaram no grupo senil a diminuição das reatividades para AR e Endostatina, e aumento para ER-_, ER-_ e VEGF, quando comparados aos camundongos jovens. Os camundongos dos grupos tratados com finasterida, SU5416 e SU5416+TNP-470, quando comparados aos do grupo senil, demonstraram de forma geral diminuição das reatividades de VEGF e ER-_ e aumento de ER-_. Já o tratamento com TNP-470 foi marcado principalmente pela redução da reatividade e dos níveis protéicos de AR e ER-_, quando comparado aos grupos jovem e senil. Desta maneira, conclui-se que a senescência favoreceu a ocorrência de alterações estruturais e/ ou funcionais que sugerem o aparecimento de lesões malignas, em virtude do desequilíbrio na sinalização entre epitélio e estroma. O tratamento com finasterida, SU5416 e SU5416+TNP- 470 mostraram-se mais ativos na regulação dos processos proliferativos através da via estrogênica / Abstract: Senescence is associated with significant changes in the hormonal environment and is a cause of morphological and functional changes in the prostate. The different biological processes that occur in the prostate are influenced by different factors such as vascular endothelial growth factor (VEGF) and Endostatin, related to angiogenesis. Also, 5_-reductase inhibitors, such as finasteride, play an important role in treatment of prostatic diseases. Thus, the aims of this study were to evaluate the structural and molecular effects of antiangiogenic therapies and finasteride on the ventral prostate of mice during senescence. Ninety 52 and 18 week old male FVB mice, were divided into groups: Young (YNG) and Senile (SEN) groups, which received 0.9% saline (5 mL/kg/day sc) injections; Finasteride (FIN) group: Finasteride (20 mg/kg, sc); SU5416 (SU) group: SU5416 (6 mg/kg, ip) injections; TNP-470 (TNP) group: TNP-470 (15 mg/kg, sc) injections and SU5416+TNP-470 (SU+TNP470) group: The same treatment as the SU and TNP-470 groups. After 21 days of treatment, samples of the ventral lobe of the prostate were collected and analyzed for morphological, immunohistochemical and Western Blotting analyses. The results demonstrated structural and molecular changes in the prostatic microenvironment during senescence, such as atrophy, inflammatory cells, and proliferative lesions, which were interrupted and/or blocked by treatment with antiangiogenic drugs and finasteride. The molecular results revealed decreased reactivity for AR and Endostatin, and an increase for ER-_, ER-_ and VEGF in the senile group, when compared to young mice. The mice in the groups treated with finasteride, SU5416 and SU5416 + TNP-470, when compared to the senile group, showed in general decreased VEGF and ER-_ reactivities and increased ER-_ reactivity. The treatment with TNP-470 however, was marked mainly by reduced AR and ER-_ reactivity and protein levels, when compared to young and senile groups. Thus, it can be concluded that senescence contributed to the occurrence of structural and/or molecular alterations that suggest the onset of malignant lesions, due to the imbalance in the signaling between the epithelium and stroma. Treatments with finasteride, SU5416 and SU5416+TNP-470, were active in the regulation of proliferative processes by means of the estrogen pathways / Mestrado / Anatomia / Mestra em Biologia Celular e Estrutural

Orientadores: Sebastião Roberto Taboga, Fernanda Cristina Alcântara dos Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T16:21:42Z (GMT). No. of bitstreams: 1 Zanatelli_Marianna_M.pdf: 26022421 bytes, checksum: 23b2b9c60198cc10c0b2a25abeb3f837 (MD5) Previous issue date: 2012 / Resumo: A próstata feminina é uma glândula funcionalmente ativa encontrada em diversas espécies de mamíferos, incluindo humanos e roedores. Em fêmeas adultas de gerbilos, a próstata apresenta localização parauretral, exibindo íntimo contato com a parede da uretra média. Esta glândula é homóloga à próstata ventral de roedores machos, sendo formada por um conjunto de ácinos e ductos inseridos em um estroma fibromuscular. O estudo da morfofisiologia prostática nas fases do ciclo estral tem demonstrado que a próstata feminina é influenciada pelas oscilações nos níveis séricos de estradiol e progesterona, com picos nas fases de estro e diestro II, respectivamente. Sendo assim, este trabalho teve como objetivo avaliar o efeito da administração combinada e prolongada de estradiol e progesterona sobre a próstata de fêmeas de gerbilo ovariectomizadas. A ovariectomia causou regressão glandular e diminuição da atividade secretora, aspectos sugeridos, entre outros, pela diminuição da massa prostática e a quase ausência de secreção glicoprotéica. Essas mudanças estão ligadas à supressão hormonal causada pela retirada dos ovários. A posterior reposição pelo estradiol e pela progesterona em associação mostrou uma grande recuperação da estrutura e fisiologia geral da próstata, evidenciada pelo aumento da altura do epitélio, da massa prostática e da atividade secretora. Os níveis hormonais aumentaram, justificando a recuperação da glândula, porém não atingiram o mesmo perfil observado no grupo controle. Também foram avaliadas as alterações na expressão de AR, ER?, ER? e no indicador de proliferação celular, PCNA, que mostraram maior imunorreatividade e maior número de células proliferativas no grupo tratado. A integridade da próstata não se relaciona apenas com os níveis de estrógeno e progesterona, mas também com o balanço cíclico entre esses hormônios no organismo feminino. Por fim, estudos sobre as ações do estrógeno e da progesterona na próstata podem abrir caminho para o desenvolvimento de tratamentos de importantes doenças prostáticas, as quais acometem tanto indivíduos do sexo masculino quanto do sexo feminino / Abstract: The female prostate is a gland functionally active found in several species of mammals, including humans and rodents. In adult female gerbils, the prostate presents paraurethral location, showing close contact with the wall of the median urethra. This gland is homologous to the ventral prostate of male rodents and it is formed by a set of acini and ducts embedded in a fibromuscular stroma. The study of prostatic morphophysiology in the estrous cycle phases has shown that the female prostate is influenced by fluctuations in serum of estradiol and progesterone, with peaks in estrous and diestrus II phases, respectively. Therefore, this study aimed to evaluate the effect of combined and prolonged administration of estradiol and progesterone on the prostate of ovariectomized female gerbil. Ovariectomy caused regression and decreased glandular secretory activity, aspects suggested by the shrinkage of the prostate and the almost absence of glycoprotein secretion. These changes are linked to hormonal supply caused by the ovaries removal. The subsequent replacement by estradiol and progesterone in combination showed a greater recovery of the structure and general physiology of the prostate, as evidenced by increased epithelial height, prostatic mass and secretory activity. The hormone levels increased, justifying the recovery of the gland, but did not achieve the same profile observed in the control group. We also evaluated the changes in the expression of AR, ER?, ER? and the cell proliferation marker, PCNA, which showed increased immunoreactivity and increased number of proliferating cells in the treated group. The integrity of the prostate is not only related to the levels of estrogen and progesterone, but also with the cyclical balance between these hormones in the female body. Finally, studies about the actions of estrogen and progesterone in prostate may be the starter for the development of treatments for important prostate diseases, which affect both males and females / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural

Orientadores: Akebo Yamakami, Laecio Carvalho de Barros, Laercio Luis Vendite / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-04T04:11:06Z (GMT). No. of bitstreams: 1 Castanho_MariaJosedePaula_D.pdf: 5605275 bytes, checksum: 589180e36f1eeebf2b8fa1ced3a0a4db (MD5) Previous issue date: 2005 / Resumo: O câncer de próstata é, atualmente, o segundo tipo de câncer com maior incidência entre a população masculina, no Brasil. Estimar o seu estágio, com as informações clínicas disponíveis para decidir a terapia a ser aplicada, é uma tarefa árdua. Neste trabalho, um modelo matemático é elaborado para auxiliar o médico na tomada de decisão. A teoria dos conjuntosfuzzy, por sua capacidade em lidar com incertezas, inerentes aos conceitos médicos, é a ferramenta utilizada, não só para desenvolver o modelo, como também para desenvolver a metodologia para sua avaliação, baseada na análise ROC (Receiver Operating Characteristic). A avaliação foi feita utilizando-se dados obtidos junto ao Instituto Americano do Câncer e permite afinnar que o sistema especialista construí do discrimina pacientes com câncer confinado à próstata daqueles com câncer não-confinado. Considerando a taxa de crescimento como um parâmetro incerto e variável na população, também é apresentado um modelo para descrever o crescimento do tumor / Abstract: Nowadays, prostate cancer is the second most common man cancer diagnosed in Brazil. Predicting the cancer stage from available clinical information to decide the therapy to be used is hard work. ln this study a mathematical model is developed to assist the physician in this task. The fuzzy sets theory provides effective tools to handle and manipulate imprecise data and to make decisions based on such data. As imprecision is a characteristic of medical concepts, this theory is utilized not oniy to develop the model as to develop the methodology for its evaluation, based on ROC (Receiver Operating Characteristic) analysis. To evaluate its performance, data from the American Cancer lnstitute were used. The results indicate that the model is able to discriminate patients with organ-confined disease from those with non-confined cancer. In addition, considering the growth rate as an uncertain, changeable parameter in the population, a model to describe the tumor growth is suggested. / Doutorado / Automação / Doutor em Engenharia Elétrica

As the most frequently diagnosed cancer in North American men, prostate cancer can progress to the androgen independent stage after initial response to androgen ablation therapy. The molecular mechanisms involved in the hormonal progression of prostate cancer are not completely understood. Here, we analyze changes in the transcriptome of prostate cancer cells at different stages of progression to reveal potential mechanisms. Applying Affymetrix GeneChip technology, we identified the transcriptomes in response to stimulation of androgen and PKA pathways in human prostate cancer cells. In addition to PSA, other common target genes were identified. Genes differentially expressed in response to androgen and stimulation of the PKA pathway in vitro were also differentially expressed during hormonal progression in vivo. Upon androgen stimulation, androgen receptor binds to a functional androgen response element within the promoter region of SESN1, a p53 targeted gene, and represses its expression. The expression of SESN1 was induced by castration in LNCaP xenografts, but the expression was eventually suppressed again in the androgen independent stage of prostate cancer. Knockdown of SESN1 promoted the proliferation of prostate cancer cells. Expression patterns of androgen-regulated genes in androgen independent tumours were revealed to be more similar to that from before castration than to the tumors under androgen ablation. The β-catenin, a potent coactivator of the androgen receptor, and Wnt pathway was deregulated in androgen-independent tumours. There was increased nuclear colocalization and interaction of androgen receptor and β-catenin with hormonal progression of prostate cancer. This study provides insight into hormonal effects on prostate cancer and possible pathways involved in the development of androgen independent disease, as well as potential therapeutic targets. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate

The mechanism by which prostate cancer progresses from androgen dependence (AD) to androgen independence/castration resistance (AI/CR) is currently a major focus of prostate cancer-related research. Prostate cancers that progress to a state of AI/CR are typically resistant to most standard types of treatments. Due to its primary role in driving normal prostate cell growth and proliferation, the androgen receptor (AR) is believed to play a key role in progression. Coregulators, or any proteins which may either enhance or abrogate AR activity, are considered to be one of the potential mechanisms by which AR function may become impaired. Cyclin G-associated kinase (GAK) was initially identified as a potential coregulator of AR in a Tup 1 repressed transactivation system. A LNCaP cDNA library was screened for proteins which interacted with the NH2-terminus of AR. GAK was isolated from three independent library clones using two different AR baits (AR 1-549 and AR 1-646). This interaction was confirmed via GST pulldown and coimmunoprecipitation experiments, and preliminary luciferase assays suggested that GAK activates AR in a hormone dependent manner. In this study, my objectives were to validate GAK’s role as a coregulator of AR and to determine if overexpressing GAK affects progression to AI. In vitro luciferase assays whereby GAK was either overexpressed or knocked down in both LNCaP and PC3 cells did not significantly affect AR activity. Xenograft experiments utilizing a doxycycline (DOX) inducible lentiviral LNCaP-GAK overexpressing stable cell line demonstrated that while GAK may not play a significant role in modulating AR activity, it may adopt a more subtle role enhancing tumour take and tumour volume growth rate in vivo. While these results could not confirm GAK to be a direct coregulator of AR, it is entirely possible that GAK may influence prostate cancer progression, albeit indirectly. Recent publications report a growing amount of evidence suggesting GAK’s involvement in the critical cellular process of clathrin coated vesicle endocytosis, the dysregulation of which could potentially indirectly affect AR regulated genes. / Medicine, Faculty of / Pathology and Laboratory Medicine, Department of / Graduate

Despite recent advances in early detection, in 2017 prostate cancer is estimated to claim over 26,000 lives in the United States alone. Prostate cancer related morbidity and mortality is a result of secondary skeletal metastasis. Therefore, better understanding of the underlying molecular mechanisms of prostate tumor cell migration and subsequent metastasis is vital for improved clinical outcomes. Interestingly, integrin α6, a laminin receptor, is highly expressed in a number of aggressive tumor types including prostate and is associated with increased metastasis and reduced patient survival. Preliminary studies by our group found that α6 integrin undergoes a post-translational modification mediated by the serine protease, uPA and its receptor, uPAR, leading to the cleavage of α6 integrin and production of the tumor specific structural variant integrin α6p. Cleavage of this laminin receptor and production of α6p variant gives rise to an aggressive phenotype, markedly increasing tumor cell migration and invasion. Thus, the work conducted here sought to identify the function and efficacy of these prominent proteins in various aspects of tumor cell migration as well as the factors regulating α6 integrin cleavage. Interestingly, utilization of a co-culture system of prostate tumor cells and macrophages found that a direct and indirect interaction between the two cell populations influenced α6 integrin cleavage. Specifically, prostate tumor cell interactions with macrophages, a known immune cell population that is highly observed in a number of primary tumors, resulted in increased protein levels of uPAR on the surface of prostate tumor cells that led to a significant production of α6p and subsequently increased invasion. Additionally, key downstream effectors of integrin signaling, including FAK, ILK, and actin, were found to regulate production of the tumor specific variant integrin α6p. Depletion of FAK, ILK, or actin, resulted in a significant increase in uPAR protein expression and subsequent α6 integrin cleavage, a regulatory event previously not known of these integrin signaling effector molecules. In addition, silencing of another prominently expressed laminin receptor, integrin α3β1, led to a significant increase in the cohesive collective phenotype exhibited by aggressive prostate tumor cells that was found to be facilitated by α6 integrin cleavage. Depletion of integrin α3β1 resulted in increased surface uPAR expression and increased lateral association with α6 integrin, which resulted in a striking increase in α6p production, a novel finding showing the regulation of one laminin receptor is dependent on the expression of another. Furthermore, the expression of α6 integrin as well as uPAR, was found to be highly expressed in aggressive pancreatic tumor cells. This expression pattern was found to significantly increase in response to the development of drug resistance and increased invasive potential. This finding showed a never before seen efficacy of integrin and uPAR expression in dictating acquired drug resistance in pancreatic tumor cells and demonstrates their potential use as prognostic biomarkers for acquired chemotherapy resistance. Taken together, the work conducted here illustrates the utility in further understanding the role of integrins and their regulation in mediating tumor cell migration and subsequent metastasis in the progression of aggressive epithelial cancers.

La Nucléophosmine (NPM1/B23) est une petite chaperonne moléculaire impliquée dans de nombreux processus cellulaires, tels que la régulation de l’expression génique ou le contrôle du cycle cellulaire. De nombreuses études rapportent une surexpression de NPM1 dans divers types de tumeurs solides incluant les cancers de la prostate, et son rôle proH prolifératif dans des lignées cellulaires tumorales d’origines variées est bien établi. La première partie de notre travail s’est attaché à évaluer le potentiel oncogénique de NPM1 dans l’épithélium prostatique in vivo. Pour cela, nous avons généré un modèle de souris transgéniques qui surexpriment NPM1 spécifiquement dans l’épithélium de la prostate. Ces animaux présentent une hyperplasie prostatique associée à une augmentation de l’index prolifératif de l’épithélium. Nos expériences révèlent que NPM1 pourrait lever la quiescence des cellules épithéliales différenciées en dérégulant l’expression de gènes clés de la régulation du cycle cellulaire, comme la Cycline E ou p27kip1. Bien que ces souris ne développent pas de lésions néoplasiques, ces données suggèrent que NPM1 participe à la carcinogenèse prostatique en association avec d’autres lésions oncogéniques. La seconde partie du travail visait à comprendre la nature des mécanismes qui supportent la surexpression de NPM1 dans les tumeurs prostatiques. Des données récentes de la littérature indiquent un enrichissement de la protéine kinase mTOR au niveau du promoteur proximal de NPM1 dans des foies de souris. Pour déterminer s’il existe un lien fonctionnel entre mTOR et NPM1, nous avons tiré parti d’un modèle de fibroblastes embryonnaires de souris invalidés pour le suppresseur de tumeur PTEN dont l’inactivation mène à une hyperactivité de mTOR. Dans ce contexte, les taux d’ARNm et de protéines NPM1 sont augmentés par rapport aux cellules sauvages. Nos résultats montrent également que mTOR contrôle l’expression de NPM1 i) en se fixant sur son promoteur et en stimulant l’expression du gène et ii) en stabilisant l’ARNm de NPM1. Nous avons confirmé le lien entre NPM1 et mTOR in vivo grâce à notre modèle de souris invalidées pour PTEN dans l’épithélium prostatique. Enfin, nous avons montré que l’expression de NPM1 est nécessaire pour transduire les effets prolifératifs de la voie PI3K/AKT/mTOR. Ces données placent donc NPM1 comme nouvel effecteur en aval de cette voie de signalisation, faisant de cette protéine une potentielle cible thérapeutique dans les tumeurs présentant une perte de PTEN. / Nucleophosmin (NPM1/B23) is a small molecular chaperone involved in a large array of cellular processes, including the regulation of gene expression and the control of the cell cycle. Several studies have reported the overexpression of NPM1 in solid tumors from various histological origin, including prostate cancer, and its proliferative impact on several human cancer cell line is being well described. The first part of our work aimed at assessing the NPM1 oncogenic properties in the prostate gland in vivo. To do so, we generated a new transgenic mouse model that overexpresses NPM1 specifically in the prostatic epithelium. These mice harbor prostatic hyperplasia associated with an increase of the ki67 proliferative index. Our molecular investigations revealed that NPM1 could be an inhibitor of the quiescent state of epithelial cells through a dysregulation of key cell-cycle controlers such as Cyclin E or p27kip1. Although these mice do not develop neoplastic lesions, our data suggest that NPM1 overexpression accelerate prostate cancer progression when associated with other oncogenic alterations. The second part of the work aimed at understanding the mechanisms underlying NPM1 overexpression in prostate tumors. The serine/threonine Kinase mTOR was recently shown to bind to the proximal promoter of NPM1 in the mouse liver. In order to characterize a fonctionnal link between NPM1 and mTOR, we took advantage of murine embryonic fibroblast (MEF) deleted for PTEN, since these cells display a constitutive mTOR activity. In such cells, NPM1 protein and mRNA levels are increased compared to wild type MEF. We also demonstrated that mTOR controls NPM1 expression i) through its binding to NPM1 promoter, thus stimulating NPM1 gene expression and ii) by stabilizing NPM1 mRNA. We have confirmed the functional link between NPM1 and mTOR in vivo in a mouse model deleted for PTEN specifically in the prostatic epithelium. Finally, we have shown that NPM1 expression is necessary for the proliferation of PTEN knock-out MEF. These data set NPM1 as a new downstream effector of the PI3K/AKT/mTOR pathway, and suggest that it could be a new potential therapeutic target in PTEN negative human prostate cancer.

Numerous studies have demonstrated that tumour cells have the ability to alter immune function to create an immune suppressed environment. This allows tumour cells to escape immune surveillance and consequently the tumour can progress. Dendritic and T cells have critical roles in immune activation and tolerance and are thus major targets of tumour-mediated immune suppression. Understanding the mechanism(s) by which tumour cells modulate the immune system will facilitate the development of immune system-based therapies for cancer treatments. In this study we sought to determine the nature of, and cellular and molecular mechanisms underlying, changes in immune status during tumour progression using mouse models of prostate cancer. Detailed analysis of the immunological status in a mouse prostate dysplasia model (12T-7slow) revealed that immune suppression accompanied tumour progression. We found that T cells isolated from tumour-bearing hosts were hypo-responsive to antigen stimulation. Furthermore, we demonstrated that CD4+CD25+ regulatory T cells were responsible, at least in part, for this alteration. Anti-CD25 antibody treatment reduced, but did not prevent, tumour growth in either a transplanted prostate tumour model or a spontaneously developing prostate tumour model. In addition, an altered dendritic cell phenotype and an elevated frequency of CD4+CD25+ regulatory T cells were observed within the tumour mass. Similar alterations were observed in the prostate-specific Pten knockout mice which develop advanced prostate adenocarcinoma. Interestingly, evidence of immune activation, such as an increased frequency of activated T cells, was detected in the tumour microenvironment in both mouse prostate tumour models. To identify factors that may play critical roles in the altered immune cell phenotype observed in the tumour microenvironment, a global gene expression profiling analysis was carried out to evaluate the changes in immune-related gene expression patterns. This analysis provided additional evidence for the co-existence of immune suppression and immune activation. Moreover, subsequent analyses suggested that one differentially expressed transcript, interferon regulatory factor 7, and its target genes might be involved in modulating immune cells and/or tumour progression. Taken together, these studies have important implications for designing specific and effective anti-tumour immune therapy strategies that involve manipulation of tumour cells, dendritic cells and regulatory T cells. / Medicine, Faculty of / Medicine, Department of / Experimental Medicine, Division of / Graduate