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Two types of estrogen binding sites were found in the rainbow trout liver cytosol, using the equilibrium binding assay. The higher affinity, lower capacity type I site had a Kd range of 0.53-5.9 nM and a concentration range of 14-95 pmoles/g protein. The lower affinity, higher capacity type II sites had a Kd range of 65-265 nM and a concentration range of 20-180 pmoles/g protein. These estrogen binding sites are both bound by ^3H-moxestrol. The estrogen binding sites in the serum were also examined and two components were found with the higher affinity component having a Kd of 2.63 nM and a concentration of 25 pmoles/g protein while the lower affinity component had a Kd of 79 nM and a concentration of 200 pmoles/g protein. However, these estrogen binding components are unable to bind the synthetic estrogen, DES, and therefore cannot account for either of the binding components found in the liver cytosol which bind DES as readily as 17β-estradiol. The cytosol estrogen binding sites bind non-estrogens in addition to estrogens. Sucrose gradient centrifugation of the cytosol yielded two estrogen binding peaks, one at 4.4S, the other at 3.7S. The heavier peak contained binding sites able to bind progesterone as well. Gel filtration of the cytosol also resulted in two peaks, one at 43,000 daltons, the other at 33,000 daltons. Again the heavier peak could be partially competed out by progesterone. The half life of these binding components was 60 minutes at 37°C, while no decrease in binding was observed after 4 hours at either 0 or 12 0 c. After 17β-estradiol treatment in vivo type I sites (relative to type II sites) were 74% depleted after 8.5 hours and 40% depleted after 24 hours. Finally, o,p'-DDT and p,p'-DDT, components of technical grade preparations of the insecticide DDT were both able to compete for estrogen binding sites in the rainbow trout liver cytosol and therefore may be able to affect the expression of estrogen inducible genes. / Thesis / Master of Science (MSc)

Yes

Most mammary development is postnatal. Mammary growth that occurs before puberty is diminutive in amount but consequential for future milk production, especially in dairy heifers. With advanced knowledge on fundamental aspects that govern prepubertal mammary development, scientists and farmers alike can ensure that heifers perform their best once they become cows. The Hippo pathway has been identified as an evolutionarily conserved pathway that regulates organ size in many animal species; it might contribute to mammary growth in dairy heifers. This pathway is mediated by yes-associated protein (YAP) and through downstream gene transcription activation, results in cell proliferation. Because YAP has never been identified in bovine mammary tissue, questions examined in this body of work mainly focused on the abundance and localization of YAP in mammary tissue of prepubertal heifers. The first trial investigated effects of in vivo estradiol administration on YAP abundance and localization in prepubertal bovine mammary epithelial and myoepithelial cells. While YAP was present in nuclei and cytoplasm of both cell types, it was also discovered that estrogen did not influence YAP abundance or location. The second research trial focused on determining the effects of in vivo estradiol blockade on YAP abundance and localization in prepubertal bovine mammary epithelial and myoepithelial cells. Similar to the first experiment, results indicate that YAP abundance and localization was not influenced by estrogen blockade. Despite not being responsive to in vivo estradiol administration (experiment 1) or estradiol blockade (experiment 2) under the conditions of our experiments, YAP was present in nearly all mammary epithelial cells and myoepithelial cells of the 21 total prepubertal heifers examined. Its presence hints at an underlying biological function but that function was not ascertained here. It will be up to the next researcher to deduce what YAP contributes to mammary growth in prepubertal dairy heifers. / MSLFS / Replacement dairy heifers are the future of any dairy herd and the successful growth and development of their mammary glands, during early stages of life, can have long term impacts on future milk production. Today, many aspects of mammary growth remain unclear. The studies described herein investigated the effects of the hormone estradiol on a biologically conserved pathway, the Hippo Pathway, which is implicated in organ size across many animal species. The first study investigated the effects of administering estradiol to heifers on Hippo pathway activity, which was thought to be implicated with mammary growth. It was discovered that estradiol administration did not affect pathway activity and therefore may not be the hormone implicated in causing growth and development through Hippo pathway signaling. The second experiment investigated the effect of blocking estradiol’s mammogenic actions on the mammary gland and whether the Hippo pathway was impacted. Results indicated that estradiol blockade did not affect pathway activity. It is possible that another hormone may be linked to mammary growth and development through Hippo pathway signaling. Overall this work contributes to the understanding of biological mechanisms involved in mammary growth and development in dairy heifers.

The incidence of cardiovascular diseases including cardiac hypertrophy and failure in pre-menopausal women is lower compared to age-matched men but the risk of heart disease increases substantially after the onset of menopause. It has been postulated that female sex hormones play an important role in cardiovascular health in pre-menopausal women. In animal studies including spontaneously hypertensive (SHR) rats, the development of cardiac hypertrophy is attenuated by 17β-estradiol treatment. Cardiac energy metabolism is crucial for normal function of the heart. In cardiac hypertrophy and heart failure, the myocardium undergoes a metabolic shift from fatty acid as primary cardiac energy source to glucose, which re-introduces the fetal type of metabolism that representing the glucose as a major source of energy. Many studies have reported that the disruption of the balance between glucose and fatty acid metabolism plays an important role in cardiac pathologies including hypertrophy, heart failure, diabetes, dilative cardiomyopathy and myocardial infarction. Glucose enters cardiomyocytes via GLUT1 and GLUT4 glucose transporters and GLUT4 is the major glucose transporter which is insulin-dependent. Cardiac-selective GLUT4 deficiency leads to cardiac hypertrophy. This shows that the decrease in cardiac glucose uptake may play a direct role in the pathogenesis of cardiac hypertrophy. Estrogens modulate glucose homeostasis in the liver and the skeletal muscle. But it is not known whether estrogens affect also cardiac glucose uptake which could provide another mechanism to explain the prevention of cardiac hypertrophy by female sex hormones. In the present study, SHR Rats were ovariectomized (OVX), not ovariectomized (sham) or ovariectomized and treated with subcutaneous 17β-estradiol. After 6 weeks of treatment, body weight, the serum levels of estrogen, insulin, intra-peritoneal glucose tolerance test (IP-GTT), myocardial glucose uptake by FDG-PET (2-(18F)-fluoro-deoxyglucose (18FDG) and Positron Emission Tomography), cardiac glucose transporter expression and localization and cardiac hexokinase activity were analyzed. As results of this study, PET analysis of female SHR revealed decreased cardiac glucose uptake in OVX animals compared to intact that was normalized by estrogen supplementation. Interestingly, there was no change in global glucose tolerance among the treatment groups. Serum insulin levels and cardiac hexokinase activity were elevated by E2 substitution. The protein content of cardiac glucose transporters GLUT-4 and GLUT-1, and their translocation as determined by fractionation studies and immuno-staining did not show any significant change by ovariectomy and estrogen replacement. Also levels of insulin receptor substrate-1 (IRS-1) and its tyrosine phosphorylation, which is required for activation and translocation of GLUT4, was un-affected in all groups of SHR. Cardiac gene expression analysis in SHR heart showed that ei4Ebp1 and Frap1 genes which are involved in the mTOR signaling pathway, were differentially expressed upon estrogen treatment. These genes are known to be activated in presence of glucose in the heart. As a conclusion of this study, reduced myocardial FDG uptake in ovariectomized spontaneously hypertensive rat is normalized by 17β-estradiol treatment. Increased myocardial hexokinase appears as a potential mechanism to explain increased myocardial glucose uptake by 17β-estradiol. Increased cardiac glucose uptake in response to 17β-estradiol in ovariectomized SHR may provide a novel mechanism to explain the reduction of cardiac hypertrophy in E2 treated SHR. Therefore, 17β-estradiol improves cardiac glucose utilization in ovariectomized SHR which may give rise to possible mechanism for its protective effects against cardiac hypertrophy. / Erkrankungen des kardiovaskulären Systems, wie beispielsweise Herzhypertrophie oder Herzinsuffizienz treten bei Frauen vor der Menopause im Vergleich zu gleichaltrigen Männern seltener auf. Das Risiko für eine solche kardiovaskuläre Erkrankung steigt jedoch drastisch mit dem Beginn der Menopause an. Aus diesem Grund wird angenommen, dass weibliche Geschlechtshormone kardioprotektive Wirkungen besitzen. Tierstudien an spontan hypertensiven Ratten (SHR) haben belegt, dass eine Herzhypertrophie durch die Behandlung der Tiere mit 17β-Estradiol abgemildert werden kann. Entscheidend für die Funktion des Myokards ist sein Energiemetabolimus, der sich im Verlauf einer Hypertrophie oder Herzinsuffizienz vom primären Fettsäurestoffwechsel auf Glucosemetabolismus umschaltet. Diese Situation entspricht der des fetalen Herzens. Viele Studien haben belegt, dass eine Störung der Balance zwischen Glucose- und Fettsäurestoffwechsel oftmals ein erstes Anzeichen für einen pathologischen Zustand des Herzens, wie z.B. Hypertrophie, Herzinsuffizienz, Diabetes, dilative Kardiomyopathie und Myokardinfarkt ist. Im gesunden Herzen gelangt Glucose über die zwei Glucosetransporter GLUT1 und GLUT4 in die Zellen des Myokards, wobei der insulinabhängige Glut4-Transporter der Hauptglucosetransporter ist. Eine GLUT4-Defizienz führt daher ebenfalls zu einer Herzhypertrophie was wiederum zeigt, dass eine verminderte Glucoseaufnahme im direkten Zusammenhang mit pathologischen Zuständen des Herzens steht. Bisherige Studien haben gezeigt, dass Östrogen an der Glucosehomöostase in Leber und Skelettmuskeln beteiligt ist. Jedoch ist wenig darüber bekannt, ob Östrogen ebenfalls in die kardiale Glucosehomöostase eingreift und inwiefern die kardioprotektive Wirkung des Östrogens in diesem Zusammenhang steht.In der vorliegenden Arbeit wurden weibliche SH-Ratten ovariektomiert (OVX), nicht ovariektomiert (sham) oder ovariektomiert und zusätzlich subkutan mit 17β-Estradiol behandelt. Nach einer Behandlungszeit von 6 Wochen wurden dann das Körpergewicht, die Serumspiegel von Östrogen, Insulin und IPGTT bestimmt, und die Glucoseaufnahme des Myokards mittels FDG-PET analysiert. Zusätzlich wurden Expression und zelluläre Lokalisation der kardialen Glucosetransporter sowie die kardiale Hexokinaseaktivität untersucht. Es konnte gezeigt werden, dass sich eine verminderte Glucoseaufnahme des Herzens bei ovariektomierten Tieren durch Östrogen-Supplementation normalisieren lässt. Eine Abweichung bezüglich der Glucosetoleranz der einzelnen Gruppen konnte nicht beobachtet werden. Jedoch konnte ein erhöhter Insulinspiegel des Serums und eine erhöhte kardiale Aktivität des Enzyms Hexokinase durch die Behandlung mit Östrogen bei den ovariektomierten Tieren beschrieben werden. Durch Fraktionierungen und immunhistologische Untersuchungen konnte kein signifikanter Unterschied in Bezug auf die Menge sowie die Translokation der Glucosetransporter GLUT1 und GLUT4 im Myokard zwischen den einzelnen Behandlungen der Tiere beschrieben werden. Ferner konnte zwischen den einzelnen Tiergruppen auch kein Unterschied zwischen dem Insulin Rezeptor Substrat-1 (IRS-1) und seiner Tyrosin-phosphorylierten Form festgestellt werden, die für die Aktivierung und Translokation des GLUT4 benötigt werden. Analysen der Genexpression in den Herzen der SH-Ratten konnten allerdings zeigen, dass die Gene ei4Ebp1 und Frap1, die im mTOR Signalweg involviert sind, bei den Östrogen-supplementierten Tieren ein abweichendes Expressionsmuster aufweisen. Über diese Gene ist bekannt, dass sie in der Gegenwart von Glucose im Herzen aktiviert werden und bei der Entstehung einer Herzhypertrophie mitwirken. Basierend auf den PET-Analysen und der Hexokinaseaktivität lässt sich als Resultat dieser Arbeit aussagen, dass Östrogen die kardiale Glucoseaufnahme in SH-Ratten fördert. Diese Ergebnisse könnten einen Hinweis auf einen noch unbekannten Mechanismus geben, um die protektive Wirkung des Östrogens im Hinblick auf die Herzhypertrophie zu erklären. Hinsichtlich der Tatsache, dass keine Veränderungen in der Translokation der GLUT4-Transporter in der Plasmamembran bei den einzelnen Behandlungen der Tiere zu verzeichnen sind, jedoch Veränderungen der Glucoseaufnahme durch die PET-Analysen dargestellt werden konnten, besteht jedoch noch Erklärungsbedarf. Es liegen diverse Studien vor, die diesen Unterschied damit erklären könnten, dass der GLUT4-Transporter in einer inaktiven Form in der Plasmamembran vorliegt bis die Glucoseaufnahme durch den GLUT4-Transporter mittels der Insulin Signaltransduktionskaskade reguliert wird.

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

Graduation date: 1996

Breast cancer is the most common malignancy affecting women and the second leading cause of death among women in the United States. Alcohol consumption is one of the few modifiable risk factors for breast cancer development but the mechanism by which it contributes to mammary cancer development and progression remains unclear, although it has been suggested that estrogen is critical for this process. To determine if alcohol promotes mammary tumor development via the estrogen pathway, estrogen receptor alpha-negative (ER[alpha]-negative) MMTV-neu mice were treated with various doses of ethanol and activation of estrogen signaling was measured. Our results showed that alcohol consumption increased estrogen signaling activation, serum estrogen levels and, most interestingly, expression of ER[alpha] in tumor tissue in the ER[alpha]-negative mice. Several lines of evidence in literature suggest that ER[alpha] expression in ER[alpha]-negative cancer cells is inhibited through epigenetic regulation. Epigenetics is the study of heritable changes in gene expression caused by mechanisms other than DNA sequence changes. Thus, to determine whether alcohol may regulate ER[alpha] re-expression in ER[alpha]-negative breast cancer cells through epigenetic mechanisms, we examined the effects of ethanol on CpG methylation and histone modifications (acetylation and methylation) of two ER[alpha]-negative breast cancer cell lines, MDA-MB-231 (human) and MMTV-neu (mouse). We also examined whether the epigenetic modifications subsequently affect the recruitment of transcriptional regulation complexes to the ER[alpha] promoter to regulate ER[alpha] transcription. Results showed that alcohol promotes ER[alpha] re-expression in these ER[alpha]-negative cell lines and that this effect was associated with decreased CpG methylation, an overall increase of histone acetylation and decrease of histone methylation, and an alteration in the enrichment of the ER[alpha] transcriptional regulation complexes (pRb2/p130-E2F4/5-HDAC1-SUV39H1-p300 and pRb2/p130-E2F4/5-HDAC1-SUV39H1-DNMT1) at the ER[alpha] promoter, which may contribute to cancer cell progression. In addition, we found that the inhibition of ER[alpha] by tamoxifen specifically blocks the effects of alcohol on ER[alpha] reactivation. To determine how alcohol promotes cell invasive ability, a critical process for cancer progression, we examined the role of two genes, metastasis suppressor Nm23 and integrin alpha-5 ITGA5, which we identified to be important for alcohol-induced breast cancer cell invasion. It has previously been shown that estrogen may regulate Nm23 expression and that estrogen regulation may be important for ITGA5-mediated cancer progression. Our results showed that alcohol promotes cancer cell invasion through the down-regulation of Nm23, which led to the subsequent increase of ITGA5 and increase of cell invasion. Collectively, data from my research strongly supports and provides evidence that alcohol promotes breast cancer development and progression through the regulation of estrogen signaling. / text

Thesis (M.S.)--University of Missouri-Columbia, 2007. / "August 2007" The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. Includes bibliographical references.