• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 592
  • 145
  • 142
  • 49
  • 40
  • 37
  • 21
  • 14
  • 13
  • 10
  • 8
  • 7
  • 6
  • 5
  • 2
  • Tagged with
  • 1287
  • 1287
  • 144
  • 109
  • 108
  • 107
  • 104
  • 88
  • 88
  • 87
  • 82
  • 81
  • 81
  • 73
  • 70
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Targeting Histone Deacetylases in Advanced Prostate Cancer

Brunner, Abigail Maria January 2015 (has links)
<p>The androgen receptor (AR) signaling axis is a well-established therapeutic target in prostate cancer, due to its central role in tumor maintenance and progression. Although patients respond initially to androgen deprivation therapies and AR antagonists, they invariably progress to a castration-resistant state. Consequently, there is an unmet need for agents that target the AR signaling axis in a unique manner. </p><p>Histone deacetylase (HDAC) inhibitors repress AR signaling and prostate cancer growth in cellular and xenograft models. However, HDAC inhibitors also induce epithelial to mesenchymal (EMT) and neuroendocrine differentiation, both of which are associated with prostate cancer progression and aggressiveness. Given that 18 different HDAC isoforms have been identified in humans, and non-selective or Class I (HDAC1, 2, 3, and 8) HDAC inhibitors have been used in most of these studies, the relative contribution of individual HDAC isoforms to AR transcriptional activity and prostate cancer pathophysiology remains to be elucidated. The overarching goals of this study were to (1) determine the role of individual Class I HDACs in AR transcriptional activity and prostate cancer growth, (2) identify selective HDAC inhibitors that have reduced adverse profiles to the treatment of prostate cancer, and (3) identify potential HDAC-interacting proteins that regulate AR target gene transcription and prostate cancer growth. </p><p>Using genetic knockdown studies and pharmacological inhibitors with isoform selectivity, we identified that HDAC3 was required for AR transcriptional activity and proliferation in cellular models of androgen-sensitive and castration-resistant prostate cancer (CRPC). Additionally, we found that RGFP966, an HDAC3-selective inhibitor, attenuated the growth of a xenograft model of CRPC. Furthermore, non-selective HDAC inhibitors induced EMT and neuroendocrine markers in prostate cancer cells, but RGFP966 treatment did not. These studies provide rationale for selective inhibition of HDAC3 for the treatment of CRPC, and could provide an explanation for the lack of success using non-selective HDAC inhibitors in clinical trials for prostate cancer.</p><p>We also assessed the role of REV-ERB alpha, an HDAC3-interacting protein, in the regulation of AR transcriptional activity and prostate cancer growth. Using siRNA knockdown studies, REV-ERB inhibitors, and overexpression studies, we concluded that REV-ERB alpha; was required for AR target gene induction and prostate cancer growth, including models of CRPC. These studies also provide rational for targeting REV-ERB alpha; for the treatment of CRPC.</p><p>Taken together, these studies identify two novel targets in the HDAC signaling axis for the treatment of prostate cancer: HDAC3 and REV-ERB alpha. Our studies provide greater insight into AR transcriptional regulation and prostate cancer pathophysiology.</p> / Dissertation
262

Race and BMI modify associations of calcium and vitamin D intake with prostate cancer

Batai, Ken, Murphy, Adam B., Ruden, Maria, Newsome, Jennifer, Shah, Ebony, Dixon, Michael A., Jacobs, Elizabeth T., Hollowell, Courtney M. P., Ahaghotu, Chiledum, Kittles, Rick A. 19 January 2017 (has links)
Background: African Americans have disproportionately higher burden of prostate cancer compared to European Americans. However, the cause of prostate cancer disparities is still unclear. Several roles have been proposed for calcium and vitamin D in prostate cancer pathogenesis and progression, but epidemiologic studies have been conducted mainly in European descent populations. Here we investigated the association of calcium and vitamin D intake with prostate cancer in multiethnic samples. Methods: A total of 1,657 prostate cancer patients who underwent screening and healthy controls (888 African Americans, 620 European Americans, 111 Hispanic Americans, and 38 others) from Chicago, IL and Washington, D.C. were included in this study. Calcium and vitamin D intake were evaluated using food frequency questionnaire. We performed unconditional logistic regression analyses adjusting for relevant variables. Results: In the pooled data set, high calcium intake was significantly associated with higher odds for aggressive prostate cancer (ORQuartile (1 vs. Quartile) (4) = 1.98, 95% C.I.: 1.01-3.91), while high vitamin D intake was associated with lower odds of aggressive prostate cancer (ORQuartile 1 vs. Quartile (4) = 0.38, 95% C.I.: 0.18-0.79). In African Americans, the association between high calcium intake and aggressive prostate cancer was statistically significant (ORQuartile 1 vs. Quartile 4 = 4.28, 95% C.I.: 1.70-10.80). We also observed a strong inverse association between total vitamin D intake and prostate cancer in African Americans (ORQuartile 1 vs. Quartile 4 = 0.06, 95% C.I.: 0.02-0.54). In European Americas, we did not observe any significant associations between either calcium or vitamin D intake and prostate cancer. In analyses stratifying participants based on Body Mass Index (BMI), we observed a strong positive association between calcium and aggressive prostate cancer and a strong inverse association between vitamin D intake and aggressive prostate cancer among men with low BMI (<27.8 kg/m(2)), but not among men with high BMI (>= 27.8 kg/m(2)). Interactions of race and BMI with vitamin D intake were significant (P-Interaction < 0.05). Conclusion: Calcium intake was positively associated with aggressive prostate cancer, while vitamin D intake exhibited an inverse relationship. However, these associations varied by race/ethnicity and BMI. The findings from this study may help develop better prostate cancer prevention and management strategies.
263

Upplevelsen av livskvalitet hos män med prostatacancer : - En litteraturstudie

Larsson, Natanael, Lidén, Fredrik January 2016 (has links)
Upplevelsen av livskvalitet hos män med prostatacancer – en litteraturstudie                                         Abstrakt Bakgrund: Prostatacancer är den vanligast förekommande cancerformen bland män i Sverige. Många män lever med biverkningar efter behandlingen, vilket kan påverka deras liv negativt och hur de upplever sin livskvalitet. Syfte: Syftet var att belysa upplevelsen av livskvalitet hos män med prostatacancer. Metod: En litteraturstudie där åtta vetenskapliga artiklar med kvalitativ ansats har granskats, sammanställts och analyserats. Resultat: Tre huvudkategorier med sex kategorier identifierades: Bemästrande av situationen – Strävan efter väbefinnande genom kontroll, Insikt i sjukdomens påverkan. Adaption till livssituation – En förändringsprocess i livet, En kamp för sinnesro. Manlig identitet – Den förändrade sexualiteten påverkar identiteten, Relationer som stöd.   Konklusion: Upplevelsen av livskvalitet varierar från individ till individ och påverkas av bl.a. biverkningar efter behandling och synen på sin livssituation. Författarna tror att litteraturstudien kan medvetandegöra sjuksköterskor om vilken påverkan prostatacancer har på männens livskvalitet. Genom att ställa personliga frågor kan sjuksköterskan ge god vård utifrån varje persons individuella behov.   Nyckelord: Prostatacancer, livskvalitet, män, anpassning / The experience of quality of life in men with prostate cancer – A literature study   Abstract Background: Prostate cancer is the most common cancer among men in Sweden. Many men live with treatment related side effects which can cause a negative effect on their lives and the experience of their quality of life. Aim: The aim was to illuminate the experience of the quality of life in men with prostate cancer. Method: A literature study of eight articles with qualitative approach. The articles result have been reviewed, compiled and analyzed. Results: Three main categories and six categories were identified: Control of the situation – quest for wellbeing through control, insight in the impact of the disease. Adaptation to life situation – a reconstruction of life, a struggle for peace of mind. Male identity – the altered sexuality affects the identity, the support of relationships. Conclusion: The experience of quality of life varies between individuals and is affected by side effects after treatment and the way they are looking at their life situation. The authors believe that this literature study can raise awareness among nurses regarding the impact prostate cancer has on men’s quality of life. By asking personal questions the nurse can provide good nursing care based on each person’s individual need.   Keywords: Prostate cancer, quality of life, men, adaptation
264

The influence of valproic acid and the role of cyclin D2 in prostate cancer

Morich, Claudia 11 April 2016 (has links)
No description available.
265

Facteurs de risques génétiques associés à la patho-biologie du vieillissement prostatique / Genetic risk factors of biology and pathology of the ageing prostate

Cornu, Jean-Nicolas 11 March 2014 (has links)
Les pathologies du vieillissement prostatique (cancer de la prostate, hyperplasie bénigne de la prostate, déficit androgénique lié à l'âge) sont fréquentes, représentant un problème de santé publique. Leur prévalence s'accroit au gré du vieillissement de la population. Si leur coïncidence épidémiologique est claire, les liens physiopathologiques les unissant restent mal connus. Grâce aux progrès de la génétique, et notamment les associations d'étude du génome entier, la quantification du risque génétique du cancer de la prostate sporadique a été documentée par la découverte de loci de susceptibilité. Néanmoins, l'utilisation de ces marqueurs en pratique courante n'a pas fait la preuve de sa rentabilité, dans le complexe débat du dépistage du cancer de la prostate. La prédisposition génétique au vieillissement pathologique bénin de la prostate, en particulier vers l'HBP, est encore très peu étudiée. De plus amples travaux sont nécessaires pour caractériser la genèse et l'évolution du vieillissement prostatique. Du point de vue du traitement, la prise en charge diagnostique du vieillissement prostatique évolue avec de nouveaux biomarqueurs. Le poids respectif de ces outils diagnostiques multiples reste à déterminer avec un triple objectif : (i) mettre en place des arbres de décision permettent de cibler les biopsies prostatiques, (ii) intégrer à la prise en charge diagnostique les pathologies bénignes comme l'HBP dont le bilan, le traitement et le suivi sont connexes à la problématique du CaP et (iii) considérer tout au long de la prise en charge les pathologies associées tel le syndrome métabolique, dans l'objectif d'une démarche multidisciplinaire. / Prostatic diseases due to ageing of the prostate gland (prostate cancer, benign prostatic hyperplasia, late onset hypogonadism) are frequent, and represent a major public health issue. Their prevalence gets higher along the ageing of the population in western countries. If an epidemiological link can be stated between these three diseases, the underlying pathophysiology remains unclear. With recent innovation in human genetics, notably genome wide association studies, the risk of non hereditary prostate cancer has been documented by the identification of susceptibility loci. However, the utility of these genetic markers in a clinical practice environment has not been yet established regarding the complex issue of prostate cancer screening. Genetic predisposition to benign prostate ageing, particularly BPH, has not been extensively studied. Additional investigations are necessary to adequately document the initial phase and evolution of the ageing prostate. From the therapeutic point of view, new biomarkers are about to modify the diagnosis of prostatic ageing. The respective role of each of these new diagnostic tools should be determined with a triple goal. First, improve decision making leading to prostatic biopsies. Then, proceed to integrative therapy of prostatic diseases (prostate cancer but also benign prostatic hyperplasia), and finally consider associated conditions, such as metabolic syndrome, to improve the level of care of the ageing male via a multidisciplinary approach.
266

Plasticita buněk karcinomu prostaty indukovaná zářením / Radiation-induced plasticity of prostate cancer cells

Kyjacová, Lenka January 2015 (has links)
Resistance of various cancers to conventional therapies including radio- and chemo- therapy is one of the most investigated phenomena in the molecular and clinical oncology. Recurrent disease is characterized by the presence of metastases, which are responsible for 90% of cancer-related mortality. Fractionated ionizing radiation (fIR) combined with surgery or hormone therapy represent the first-choice treatment for medium to high risk localized prostate carcinoma (PCa). In PCa, the failure of radiotherapy (RT) is often caused by radioresistance and further dissemination of escaping (surviving) cells. To investigate the radioresistance-associated phenotype, we exposed four metastasis- derived human PCa cell lines (DU145, PC-3, LNCaP, and 22RV1) to clinically relevant daily fractions of ionizing radiation (fIR; 35 doses of 2 Gy) resulting in generation of two surviving populations: adherent senescent-like cells expressing common senescence-associated markers and non-adherent anoikis-resistant stem cell-like cells with active Notch signaling and expression of stem cell markers CD133, Oct-4, Sox2, and Nanog. While the radioresistant adherent cells were capable to resume proliferation shortly after the end of irradiation, the non- adherent cells started to proliferate only after their reattachment...
267

Efeito da cafeína e do cádmio na próstata do rato wistar púbere : proliferação e morte de células epiteliais e alterações estromais /

Lacorte, Lívia Maria. January 2008 (has links)
Resumo: O câncer de próstata e a hiperplasia prostática benigna são as duas principais afecções do sistema genital masculino após a quinta década de vida. Além de aspectos étnicos, etários, genéticos, estudos sobre a contaminação ambiental por agentes químicos carcinogênicos, dos hábitos alimentares e do estilo de vida vêm adquirindo importância no entendimento das causas destas afecções. A exposição a contaminantes ambientais, tais como o cádmio e a ingestão de bebidas contendo cafeína têm sido associados com o aparecimento do câncer de próstata e com a hiperplasia prostática benigna, respectivamente. Além disso, existem evidências experimentais de que a exposição da próstata em períodos críticos da sua morfogênese e de rápido crescimento a disruptores endócrinos pode gerar alterações permanentes que levarão ao aparecimento de afecções nos indivíduos adultos e idosos. Neste sentido, por exemplo, a partir da puberdade é comum os homens adquirirem o hábito de fumar e/ou de ingerir bebidas estimulantes, estando, portanto, expostos ao cádmio, presente na fumaça do cigarro, e/ou a cafeína, presente nas bebidas. Desta forma, este trabalho avaliou os efeitos, isolados e combinados, do cádmio e da cafeína, em baixas concentrações, sobre a morfologia e fisiologia da próstata de ratos púberes. Para isto, ratos Wistar com 60 dias de idade foram divididos em quatro grupos (n=15), os quais receberam, via oral, na água de beber, pelo período de 30 dias: Água, Cádmio (10ppm), Cafeína (10mg/l) ou Cafeína+Cádmio, e as próstatas dorsolaterais e ventrais foram processadas histologicamente e foram feitas análises morfológicas, citoquímicas para fibras de colágeno, morfométricas e imunocitoquímicas. Também foram determinadas as concentrações plasmáticas de cádmio e testosterona e intra-prostática de cádmio no... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The prostate cancer and the benign prostate hyperplasia are the main male genitourinary system diseases after the fifty. Besides ethic, age and genetic aspects, studies about environmental contamination, diet and life stile have also emerged as important factors involved in the etiology of these diseases. The exposure to cadmium and the intake of caffeine-containing beverage have been associated with appearing of the prostate cancer and benign prostate hyperplasia, respectively. Furthermore, there are experimental evidences that prostate exposures to endocrine disruptors during a critic period of its morphogenesis and growth may influence the onset of late-life disease. In this sense, for example, from puberty on, many males became smokers and/or start to intake energetic beverage or even yet coffee, thus being exposed to cadmium, from cigarettes and/or to caffeine, from beverage. So, here we investigated the effects of cadmium and caffeine, isolated or combined, in low doses, on rat prostate morphology during puberty. For this, male Wistar rats (n=60), 2 months-old, were divided into four experimental groups (n=15), that received by drinking water and during 30 days: tap water, cadmium (10ppm), caffeine (10ppm), cadmium plus caffeine. The prostatic lobes ventral and dorsolateral were dissected out, weighted and processed for histology. It were made morphological and morphometrical analyses; cytochemistry for collagen and reticular fibers and immunocytochemistry for Ki-67. It were also determined the plasma concentrations of testosterone and cadmium and the ventral lobe intraprostatic concentration of cadmium. The plasma and intraprostatic concentrations of cadmium were increased in the animals treated with cadmium and cadmium plus caffeine. In the conditions of this experiment, the exposure to these two agents did not alter significantly neither the prostatic... (Complete abstract click electronic access below) / Orientador: Sérgio Luis Felisbino / Coorientador: Antônio Francisco Godinho / Banca: Sebastião Roberto Taboga / Banca: Patrícia Aline Boer / Mestre
268

Role of High Mobility Group A2 (HMGA2) in Prostate Cancer

Hawsawi, Ohuod 20 May 2019 (has links)
High mobility group A2 (HMGA2) is a non-histone protein highly expressed during the development but is low or absent in most adult tissues. Epithelial-mesenchymal transition (EMT) plays a critical role in prostate cancer progression and metastasis. HMGA2 has been shown to promote EMT in separate studies. Interestingly, wild-type HMGA2 and truncated (lacking the 3’UTR) HMGA2 isoforms are overexpressed in many cancers. However, there are no studies on the role of each isoform in prostate cancer progression. We hypothesized that wild-type and truncated HMGA2 promotes prostate cancer progression by different mechanisms. We analyzed the expression of HMGA2 in the prostate panel by western blot analysis and the localization in prostate tissue microarray by immunohistochemistry. We stably overexpressed wild-type and truncated HMGA2 cDNA in LNCaP cells and measured the expression and the localization of HMGA2 as well as EMT markers. We also performed the migration and cell viability assays. We analyzed phospho-ERK in cells overexpressing HMGA2 as well as inhibition with U0126 (MAPK inhibitor). To explore the role of truncated HMGA2, we measured the reactive oxygen species (ROS) concentration by DCFDA dye, as well as analyzing Jun-D as a putative downstream effector of HMGA2. Additionally, we knocked down Jun-D and performed the migration and cell viability assays. We treated ARCaP-M mesenchymal cells with camalexin, a 3-thizol-2-yl-indole (a natural product, as a candidate to target HMGA2) in vitro and in vivo in nude mice. Our results showed an increase in nuclear HMGA2 expression with prostate cancer progression as compared to normal tissue. LNCaP cells overexpressing wild-type but not truncated HMGA2 displayed nuclear localization and induced EMT via the ERK1/2 pathway, and this effect could be reversed by treating the cells with U0126. Conversely, truncated HMGA2 displayed cytoplasmic expression and increased prostate cancer migration via increasing Jun-D expression and ROS; this could be antagonized by Jun-D knockdown. Finally, treating ARCaP-M aggressive prostate cancer cells with camalexin reduce its expression in vitro and in vivo. In conclusion, both wild-type and truncated HMGA2 induce prostate cancer progression by different mechanisms which may be targeted by camalexin.
269

Deformable models for adaptive radiotherapy planning

Cheng, Kun January 2016 (has links)
Radiotherapy is the most widely used treatment for cancer, with 4 out of 10 cancer patients receiving radiotherapy as part of their treatment. The delineation of gross tumour volume (GTV) is crucial in the treatment of radiotherapy. An automatic contouring system would be beneficial in radiotherapy planning in order to generate objective, accurate and reproducible GTV contours. Image guided radiotherapy (IGRT) acquires patient images just before treatment delivery to allow any necessary positional correction. Consequently, real-time contouring system provides an opportunity to adopt radiotherapy on the treatment day. In this thesis, freely deformable models (FDM) and shape constrained deformable models (SCDMs) were used to automatically delineate the GTV for brain cancer and prostate cancer. Level set method (LSM) is a typical FDM which was used to contour glioma on brain MRI. A series of low level image segmentation methodologies are cascaded to form a case-wise fully automatic initialisation pipeline for the level set function. Dice similarity coefficients (DSCs) were used to evaluate the contours. Results shown a good agreement between clinical contours and LSM contours, in 93% of cases the DSCs was found to be between 60% and 80%. The second significant contribution is a novel development to the active shape model (ASM), a profile feature was selected from pre-computed texture features by minimising the Mahalanobis distance (MD) to obtain the most distinct feature for each landmark, instead of conventional image intensity. A new group-wise registration scheme was applied to solve the correspondence definition within the training data. This ASM model was used to delineated prostate GTV on CT. DSCs for this case was found between 0.75 and 0.91 with the mean DSC 0.81. The last contribution is a fully automatic active appearance model (AAM) which captures image appearance near the GTV boundary. The image appearance of inner GTV was discarded to spare the potential disruption caused by brachytherapy seeds or gold markers. This model outperforms conventional AAM at the prostate base and apex region by involving surround organs. The overall mean DSC for this case is 0.85.
270

A functional study of an orphan nuclear receptor estrogen-related receptor α in prostate cancer. / α亞型雌激素相關受體在前列腺癌中的功能研究 / Functional study of an orphan nuclear receptor estrogen-related receptor alpha in prostate cancer / CUHK electronic theses & dissertations collection / α ya xing ci ji su xiang guan shou ti zai qian lie xian ai zhong de gong neng yan jiu

January 2012 (has links)
研究背景和研究目的 / 前列腺癌是許多西方國家男性人群中最常見的惡性腫瘤。最新癌症統計結果表明,前列腺發病例和致死率在亞洲國家尤其是中國和香港地區呈迅猛上升趨勢(2009年,本港前列腺癌發病率列所有腫瘤發病率中第三位,致死率列第五位)。目前前列腺癌治療策略主要集中在拮抗雄激素信號通路。然而,臨床實踐表明,這種治療方式除了引起由於體內激素水平失調產生的一系列副作用之外,往往導致疾病進展到令人棘手的去勢治療無效階段。因此,從分子水平更為深入的理解前列腺癌疾病進展過程對於最終攻克前列腺癌具有重要的研究價值。雌激素相關受體是孤兒核受體的亞組之一,包括 α, β, γ三個亞型。該組受體在結構上與α亞型雌激素受體具有很高的同源性。已有研究表明,α亞型雌激素相關受體直接调控涉及氧化磷酸化,線粒體生物發生和脂肪酸氧化的相關基因表達,從而在細胞能量代謝調節中發揮至關重要作用。最新研究發現, α亞型雌激素相關受體的高表達在包括乳腺癌和前列腺癌在內的一系列腫瘤中與疾病的進展和不良預後高度相關。這提示該受體可能參與這些腫瘤的惡性進展。腫瘤細胞對低氧環境的耐受是實體腫瘤的標誌性表型之一,同時也有研究表明這一機制可能在癌細胞的惡性克隆選擇中發揮了重要作用。在眾多低氧耐受的機制中,細胞能量代謝方式轉換被研究人員看作重要的調節通路之一。考慮到前列腫瘤的低氧微環境以及α亞型雌激素相關受體在能量代谢過程的重要調節作用,有理由推測在該受體可能在前列腺癌細胞低氧耐受中發揮了積極的作用進而促進前列腺癌的惡性進展。 / 材料和方法 / 為了研究α亞型雌激素相關受體在前列腺癌細胞低氧耐受中的功能,本次研究採取了下列實驗方法:1)用免疫組化方法考察α亞型雌激素相關受體在人前列腺癌組織中的表達情況;2)用合適的前列癌細胞系建立α亞型雌激素相關受體穩定過表達細胞系同時研究這些穩轉細胞系的體外生長表型;)研究雌激素相關受體穩定過表達細胞系在低氧环境下的體外生長表型;)研究雌激素相關受體穩定過表達細胞系在免疫缺陷小鼠中的致瘤能力同時用免疫組化方法考察其腫瘤血管生成情況;)用定量 PCR和免疫印跡(Western blot)方法檢測低氧誘導因子-1α亞基(HIF-1α)及其信號通路中相關基因在α亞型雌激素相關受體穩定過表達細胞系中的表達水平,同時用雙螢光素酶報告基因方法考察α亞型雌激素相關受體對低氧誘導因子‐1(HIF-1)靶基因啟動子的轉錄激活效應;5)用 shRNA介導的基因阻斷的方法進一步考察α亞型雌激素相關受體對前列腺癌細胞低氧耐受的影響;6)通過觀考察用α亞型雌激素相關受體選擇性抑製劑 XCT790處理細胞對其在低氧環境下的體外生長情況的作用,進一步闡明 α亞型雌激素相關受體對前列腺癌細胞低氧耐受的影響;7)用免疫印跡 (Western blot),免疫共沉澱 (Co-IP)和熒光能量共振轉移(FRET)分析的方法考察α亞型雌激素相關受體對低氧誘導因子‐1α亞基表蛋白表達和穩定性以及對低氧誘導因子 -1信號通路的影響。 / 結果 / 本研究所得得到的結果簡要總結如下:1)α亞型雌激素相關受體在前列癌組織中的免疫反應性呈現隨著惡性程度升高而增加的趨勢;2)α亞型雌激素相關受體在人前列腺癌細胞系 LNCaP中的過表達能提升其在常氧和低氧環境下的體外細胞增殖,細胞集落形成,細胞對胞外基質的粘附以及細胞侵襲能力; 3) α亞型雌激素相關受體在人前列腺癌細胞系 LNCaP中的過表達能促進其體內腫瘤形成及腫瘤血管生成; 4)過表達 α亞型雌激素相關受體能上調低氧誘導因子-1α亞基的蛋白水平並提高其轉錄活性;5)shRNA介導的α亞型雌激素相關受體 mRNA阻斷可以削弱人前列腺癌細胞系 LNCaP細胞在低氧環境下的體外生長能力;6)在体外用α亞型雌激素相關受體選擇性抑製劑 XCT790处理人前列腺癌細胞系 LNCaP細胞可能通過減少低氧誘導因子‐1α亞基蛋白表達水平從而抑制其在低氧環境下的細胞生長能力;7)α亞型雌激素相關受體可以直接與低氧誘導因子-1α亞基相互作用,並且這種相互作用可能有助於抑制低氧誘導因子-1 α亞基的蛋白降解。 / 結論 / 本研究獲得結果提示,α亞型雌激素相關受體可能通過提高低氧誘導因子-1α亞基的蛋白水平及激活低氧誘導因子-1信號通路從而促進前列腺癌細胞在低鹽環境下的細胞生長能力。体外用 shRNA介導的α亞型雌激素相關受體 mRNA阻斷方法和α亞型雌激素相關受體選擇性抑製劑处理都有可能通過阻止低氧誘導因子‐1α亞基以削弱前列腺癌細胞在低鹽環境下的細胞生長能力。同時, α亞型雌激素相關受體能直接與低氧誘導因子-1 α亞基相互作用而這種相互作用有可能有助於抑制其蛋白降解,這些結果提示 α亞型雌激素相關受體可能在前列腺癌進展過程中的低氧耐受中發揮積極作用。 / Background and aims of study / Prostate cancer is the most common cancer in many Western counties among the male populations. Latest cancer statistics also show that its incidence and mortality rates are rapidly increasing in China and Hong Kong (Prostate cancer ranked the 3rd common cancer and 5th cancer causing death in Hong Kong in 2009). Current therapeutic strategies of prostate cancer mainly target to the antagonizing androgen signaling pathway, which usually drives the disease to the impasse of castration resistance albeit the side effects caused by the imbalance of hormone. The substantial clinical significance of prostate cancer is urgent to better understand the progression of this disease. Estrogen-related receptors (α,β,γ) are a subgroup of ligand-independent orphan nuclear receptors, which is constitutively activated without binding any physiological ligands and all share high homology with the estrogen receptor alpha (ER α) structurally. Previous studies indicates that ERR α plays a pivotal role in cellular energy home stasis regulation, target genes of which are involved in the procedures of oxidative phosphorylation, mitochondrial biogenesis and fatty acid oxidation. Recent studies reveals that high expression of ERR α may be useful as a poor prognostic marker in both hormone-dependent and hormone-independent cancers (including breast cancer and prostate cancer), which implicates this nuclear receptor may be involved in the advanced malignant progression of these cancers. Adaptation to hypoxia is one of the hallmark features of solid tumors and it is conceived to play an important role in malignant clonal selection of cancer cells. Among the diverse mechanisms on cellular hypoxia adaptation, energy metabolism reprogramming is characterized and considered as a critical regulatory pathway. Given the hypoxic microenvironment of prostate cancer and the energy regulatory role of ERR α, it is hypothesized that ERR α might play an active role in the cellular hypoxic adaptation of prostate cancer hence advancing the progre sion of this disease. / Materials and methods / To investigate the functional significance of ERR α in cellular hypoxic adaptation of prostate cancer, the following experimental approaches were employed and performed in my thesis study: 1) to survey the expression pattern of ERR α in human prostate cancer tissues by immunohistochemical staining; 2) to generate ERR α-stable expressing cell lines in selected prostate cancer cell lines and functionally characterize their in vitro phenotypes under normoxia condition; 3) to characterize in vitro hypoxic-response phenotypes of ERR α-infectants; 4) to determine the tumorigenicity of ERR α-infectants in immuno-deficient SCID mice and to investigate their tumor angiogenesis by immunohistochemical staining; 5) to determine the HIF-1α signal cohort in ERR α-infectants by both RT-PCR and immuno blot analysis and to investigate the transactivation effect of ERR α on HIF-1 targeting genes promoters by dual luciferase reporter assay; 6) to further characterize the hypoxic adaptation phenotypes induced by ERR α transduction using shRNA-mediated gene knockdown approach; 7) to further elucidate the effect of ERR α on the hypoxic cell growth regulation of prostate cancer by treating ERR α-infectants with an ERR α-selective antagonist XCT790; 8) to further investigate the mechanisms via which ERR α interferes with the protein expression or stabilization of HIF-1α as well as HIF-1 signal cohort using immuno blot analysis, immunoprecipitation assays and fluorescence resonance energy transfer (FRET) analysis. / Results / My results are briefly summarized as follows: 1) ERR α exhibited an increased immuno expression pattern in high-grade prostate cancer; 2) Ectopic expression of ERR α in LNCaP prostate cancer cell line could promote its in vitro cell proliferation, clonal formation, cell-extracellular matrix attachment and cell invasion capacities under both normoxic and hypoxic conditions; 3) Ectopic expression of ERR α in LNCaP prostate cancer cell line could promote its in vivo tumorigenicity and tumor angiogenesis; 4) Overexpression of ERR α could up-regulate protein level of hypoxia regulatory transcriptional factor-1(HIF-1) α subunit (HIF1-α) and enhance its transcriptional activity; 5) mRNA knock-down of ERR α could attenuate in vitro cell growth capacity of LNCaP prostate cancer cell line under hypoxic condition; 6) Treatment with an ERR α specific antagonist XCT790 could inhibit in vitro hypoxic cell growth of LNCaP cells via its effect on decreasing the protein level of HIF-1α; 7) ERR α could physically interact with HIF-1α and such ERR α-HIF1-α interaction might help to inhibit protein degradation of HIF-1α. / Conclusion / The results obtained in this study indicated that ERR α could promote the hypoxic cell growth of prostate cancer via its enhancing the protein level of HIF-1α and activation of HIF-1 signal cohort. Both treatment with ERR α selective antagonist and down-regulating of ERR α by shRNA-mediated gene knockdown approach could attenuate the hypoxia adaptation of prostate cancer cells, which might be mediated by their suppression of the protein level of HIF1α. ERR α could directly interact with HIF-1α and such interaction might help to suppress the protein degradation of HIF1α, suggesting that ERR α may play an active role in hypoxic adaptation in advancing of prostate cancer. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zou, Chang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 138-160). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / ABSTRACT --- p.i / ACKNOWLEDGEMENTS --- p.viii / PUBLICATIONS --- p.ix / CONTENTS --- p.x / ABBREVIATIONS --- p.xiii / Chapter CHAPTER 1 --- Introduction --- p.1 / Chapter 1.1 --- Prostate cancer --- p.2 / Chapter 1.1.1 --- Epidemiology --- p.2 / Chapter 1.1.2 --- Risk factors --- p.3 / Chapter 1.1.3 --- Patho-physiology --- p.6 / Chapter 1.1.4 --- Diagnosis and treatment --- p.8 / Chapter 1.2 --- Androgen,androgen receptor and prostate cancer --- p.10 / Chapter 1.2.1 --- Androgen and androgen receptor --- p.10 / Chapter 1.2.2 --- Castration Resistance Prostate Cancer (CRPC) --- p.12 / Chapter 1.2.2.1 --- Overexpression of AR --- p.13 / Chapter 1.2.2.2 --- Increasing sensitivity to and rogen --- p.13 / Chapter 1.2.2.3 --- AR mutation --- p.14 / Chapter 1.2.2.4 --- Deregulation of AR regulator factors --- p.15 / Chapter 1.2.2.5 --- Outlaw pathway --- p.15 / Chapter 1.2.2.6 --- AR-independent pathway --- p.16 / Chapter 1.3 --- Estrogen and prostate cancer --- p.17 / Chapter 1.3.1 --- Overview of estrogen and estrogen receptors --- p.17 / Chapter 1.3.2 --- Estrogen signaling pathway andprostatecancer --- p.18 / Chapter 1.4 --- Nuclear receptors --- p.20 / Chapter 1.4.1 --- Overview of NRs superfamily --- p.20 / Chapter 1.4.2 --- Classification --- p.21 / Chapter 1.4.3 --- NRs as therapeutic targets for cancer treatment --- p.23 / Chapter 1.5 --- Estrogen-related receptors --- p.25 / Chapter 1.5.1 --- NR3B subgroup --- p.25 / Chapter 1.5.2 --- Isoforms --- p.26 / Chapter 1.5.3 --- Structure --- p.27 / Chapter 1.5.4 --- Ligand --- p.28 / Chapter 1.5.5 --- Co-regulators --- p.31 / Chapter 1.5.6 --- Tissue-specific expression pattern and identifiedfunction --- p.32 / Chapter 1.5.6.1 --- Tissue-specific expression pattern --- p.32 / Chapter 1.5.6.2 --- Identified physiological function of ERRs --- p.33 / Chapter 1.5.7 --- ERRs and cancer --- p.35 / Chapter 1.5.7.1 --- ERRβ/γ and cancer --- p.35 / Chapter 1.5.7.2 --- Expression of ERRα in cancer --- p.37 / Chapter 1.5.7.3 --- Identified functional roles of ERRα in cancer --- p.40 / Chapter 1.5.7.4 --- Regulation of ERRα in cancer cells --- p.42 / Chapter 1.6 --- Hypoxiaadaptation andcancer --- p.47 / Chapter 1.6.1 --- HIFs isoforms and structure --- p.47 / Chapter 1.6.2 --- Structure --- p.48 / Chapter 1.6.3 --- Regulation of HIF-1α expression --- p.49 / Chapter 1.6.3.1 --- Regulation of HIF-1α mRNA transcription --- p.49 / Chapter 1.6.2.2 --- Regulation of HIF-1α mRNA transcription --- p.50 / Chapter 1.6.2.3 --- O₂-dependent regulation of stability of HIF-1α protein --- p.51 / Chapter 1.6.2.4 --- O₂-independent regulation of HIF-1α --- p.52 / Chapter 1.6.2.5 --- Genetranscriptional regulation role of HIFs --- p.54 / Chapter 1.6.3 --- HIFs and cancer --- p.55 / Chapter 1.6.3.1 --- Overview --- p.55 / Chapter 1.6.3.2 --- Expression of HIF-1α in cancer progression --- p.55 / Chapter 1.6.3.2 --- Functional roles of HIF-1α in cancer progression --- p.56 / Chapter CHAPTER 2 --- Aims of study --- p.58 / Chapter CHAPTER 3 --- Materials and methods --- p.61 / Chapter 3.1 --- Cell lines and cell culture --- p.62 / Chapter 3.2 --- Human Prostatic Tissues --- p.64 / Chapter 3.3 --- RNA isolation and Reverse transcriptional-PCR --- p.64 / Chapter 3.3.1 --- Total RNA extraction --- p.64 / Chapter 3.3.2 --- Reverse transcription reaction --- p.65 / Chapter 3.3.3 --- Polymerase Chain Reaction for gene expression detection --- p.66 / Chapter 3.4 --- Plasmids construction --- p.69 / Chapter 3.4.1 --- Genomic DNA extraction --- p.69 / Chapter 3.4.2 --- PCR for cloning and sub-cloning --- p.70 / Chapter 3.4.3 --- PCR for mutant generation --- p.70 / Chapter 3.4.4 --- Restriction enzymes cut and ligation --- p.71 / Chapter 3.5 --- Antibody and reagents --- p.73 / Chapter 3.6 --- Immunohistochemistry --- p.74 / Chapter 3.7 --- Western Blot Analysis --- p.75 / Chapter 3.7.1 --- Protein extraction --- p.75 / Chapter 3.7.2 --- Electrophoresis, Protein blotting and Colorimetric detection --- p.76 / Chapter 3.8 --- Retroviral transduction and generation of ERRα poolandstable clones --- p.77 / Chapter 3.9 --- In vitro Cell Growth Assays --- p.77 / Chapter 3.9.1 --- Cell counting --- p.77 / Chapter 3.9.2 --- 5-Bromodeoxyuridine (BrdU) incorporation assay --- p.78 / Chapter 3.9.3 --- MTT assay --- p.79 / Chapter 3.9.4 --- In vitro clonal formation assay --- p.79 / Chapter 3.10 --- Cell attachment assay --- p.80 / Chapter 3.11 --- Transwell cell invasion assay --- p.81 / Chapter 3.12 --- In vivo tumorigenicity assay --- p.81 / Chapter 3.13 --- RNA interference --- p.82 / Chapter 3.14 --- Transient Transfection and Luciferase Reporter Assay --- p.83 / Chapter 3.15 --- Immuno-precipitation (IP) assay --- p.84 / Chapter 3.16 --- Fluorescence Resonance Energy Transfer (FRET) detection --- p.85 / Chapter 3.17 --- In vitro treatment with XCT790, cycloheximide and MG-132 --- p.86 / Chapter CHAPTER 4 --- Reuslts --- p.88 / Chapter 4.1 --- ERRα exhibits an increased expression pattern in high grade prostate cancer --- p.89 / Chapter 4.2 --- Ectopic expression of ERRα in LNCaP prostate cancer cell line can promote its in vitro cell proliferation, clonal formation, cell attachment and cell invasion capacity under normoxic condition --- p.91 / Chapter 4.3 --- Ectopic expression of ERR α in LNCaP prostate cancer cell line can promote its in vitro cell proliferation, clonal formation, cell attachment and cell invasion capacities under hypoxic condition --- p.94 / Chapter 4.4 --- Ectopic expression of ERR α in LNCaP prostate cancer cells can promote their in vivo tumorigenicity and tumor angiogenesis. --- p.97 / Chapter 4.5 --- Overexpression of ERRα can up‐regulate protein level of HIF-1α and enhance its transcriptional activity --- p.99 / Chapter 4.6 --- mRNA Knock-down of ERRα can attenuate in vitro cell growth of LNCaP prostate cancer celll line under hypoxic condition --- p.107 / Chapter 4.7 --- Treatment with an ERRα specific antagonist XCT790 can inhibit in vitro hypoxic cell growth of LNCaP cells via its effect on decreasing the protein level of HIF-1α --- p.110 / Chapter 4.8 --- ERRα can physically interact with HIF-1α and such ERRα-HIF-1α interaction helps to inhibit protein degradation of HIF-1α --- p.114 / Chapter CHAPTER 5 --- Discussion --- p.119 / Chapter CHAPTER 6 --- Summary --- p.134 / References --- p.138

Page generated in 0.0968 seconds