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  • 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.
461

Novel Roles of RNase L in Prostate Cancer

Dayal, Shubham 18 October 2017 (has links)
No description available.
462

The effect of finasteride and dutasteride on the growth of wpe1-na22 prostate cancer xenografts in nude mice

Opoku-Acheampong, Alexander Boadu January 1900 (has links)
Master of Science / Department of Human Nutrition / Brian Lindshield / 5α-reductase 1 (5αR1) and 5α-reductase 2 (5αR2) convert testosterone into the more potent androgen, dihydrotestosterone (DHT), that is responsible for regulating prostate growth and proliferation. 5αR2 is the main isoenzyme in normal prostate tissue, however prostate tumors have increased 5αR1 and decreased or unchanged 5αR2 expression. Previously, finasteride (5αR2 inhibitor) treatment begun 3 weeks after tumor implantation had no effect on Dunning R3327-H rat prostate tumor growth. We believe the tumor compensated for finasteride treatment by increasing tumor 5αR1 activity to produce dihydrotestosterone to stimulate its growth. We hypothesize that finasteride treatment would not significantly alter tumor growth even if begun before tumor implantation, while dutasteride (dual 5αR1 & 5αR2 inhibitor) treatment would decrease tumor growth regardless if treatment is begun before or after tumor implantation. Sixty, 8-week old male nude mice were randomized to Control, Pre-Finasteride, Post-Finasteride, Pre-Dutasteride and Post-Dutasteride diet groups (all diets contained 83.3 mg drug/kg diet). Pre groups began their treatment diets 1-2 weeks prior to tumor implantation, while post groups began their treatment diets 3 weeks after tumor implantation. Tumors were implanted by subcutaneous injection of 1 x 10⁵ WPE1-NA22 human prostate cancer cells in Matrigel™ and allowed to grow for 22 weeks. Tumor areas, body weights, and feed intakes were measured weekly. At study conclusion, prostate and seminal vesicle weights were significantly decreased in all treatment groups versus the control. Dutasteride intake also significantly reduced seminal vesicle weights compared to finasteride intake. There were no significant differences in final tumor areas or tumor weights between groups, likely due to poor tumor growth. In follow-up studies, proliferation of WPE1-NA22 prostate cancer cells, and its parent line RWPE-1 prostate epithelial cells, were unaltered by treatment with testosterone, DHT, or the synthetic androgen mibolerone, suggesting that these cell lines are not androgen-sensitive. Thus, the lack of response to androgen treatment by WPE1-NA22 prostate cancer cells may explain the inadequate tumor growth observed.
463

Prostate transglutaminase (TGase-4, TGaseP) enhances the adhesion of prostate cancer cells to extracellular matrix, the potential role of TGase-core domain

Jiang, Wen, Ye, Lin, Sanders, Andrew, Ruge, Fiona, Kynaston, Howard, Ablin, Richard, Mason, Malcolm January 2013 (has links)
BACKGROUND:Transglutaminase-4 (TGase-4), also known as the Prostate Transglutaminase, is an enzyme found to be expressed predominately in the prostate gland. The protein has been recently reported to influence the migration and invasiveness of prostate cancer cells. The present study aimed to investigate the influence of TGase-4 on cell-matrix adhesion and search for the candidate active domains] within the protein.METHODS:Human prostate cancer cell lines and prostate tissues were used. Plasmids that encoded different domains and full length of TGase-4 were constructed and used to generate sublines that expressed different domains. The impact of TGase-4 on in vitro cell-matrix adhesion, cell migration, growth and in vivo growth were investigated. Interactions between TGase-4 and focal adhesion complex proteins were investigated using immunoprecipitation, immunofluorescence and phosphospecific antibodies.RESULTS:TGase-4 markedly increased cell-matrix adhesion and cellular migration, and resulted in a rapid growth of prostate tumours in vivo. This effect resided in the Core-domain of the TGase-4 protein. TGase-4 was found to co-precipitate and co-localise with focal adhesion kinase (FAK) and paxillin, in cells, human prostate tissues and tumour xenografts. FAK small inhibitor was able to block the action mediated by TGase-4 and TGase-4 core domain.CONCLUSION:TGase-4 is an important regulator of cell-matrix adhesion of prostate cancer cells. This effect is predominately mediated by its core domain and requires the participation of focal adhesion complex proteins.
464

The role of homeobox gene NKX3.1 in prostate cancer

Patel, Ruchi January 2014 (has links)
NKX3.1, a prostate specific homeobox gene is a known marker of prostate epithelium during embryogenesis and is also expressed subsequently through different stages of prostate differentiation. However, all studies on NKX3.1 are focused on its regulation by androgen receptor (AR). The aim of this project is to establish the role of NKX3.1 in differentiation in prostate cancer, independent of AR regulation. In this thesis, I characterize the cell lines in terms of their differentiation capabilities in 3D, expression levels of NKX3.1 and the mismatch repair status. The genes potentially involved in differentiation and regulators of NKX3.1 are also identified using microarray data of the cell lines (<b>Chapter 3</b>). Although NKX3.1 plays a key role in prostate development no studies have been conducted on the effect of NKX3.1 expression on differentiation capabilities of prostate cell lines. In <b>Chapter 4</b>, this was investigated by siRNA mediated knockdown of NKX3.1 in 22Rv1 cell line and overexpression of NKX3.1 in PC3 (designated PC3-Nkx3.1) and PNT1a cells followed by growth in 3D. These functional studies show that the expression of NKX3.1 is vital for lumen formation in 3D, which is used as a measure of differentiation. The microarray data and overexpression of NKX3.1 studies suggest that this gene may also be involved in inhibiting epithelial to mesenchymal transition (EMT). Homeobox B13 (HOXB13) was identified as one of the downstream targets of NKX3.1. NKX3.1 and HOXB13 expression levels are positively correlated not only in the panel of prostate cell lines but also in the NKX3.1 overexpression and knockdown studies (<b>Chapter 5</b>). The results of the work presented in this thesis demonstrate that there is a striking parallel between the function of NKX3.1 in prostate and Caudal-type homeobox 1 (CDX1) in the colon and rectum. In conclusion, NKX3.1 plays a key role as a tumour suppressor in prostate cancer by controlling differentiation of prostate cancer cells.
465

Att leva ett förändrat liv : Mäns upplevelse av att leva med prostatacancer / To live a changed life : Men´s experience to live with prostate cancer

Bogren, Emma, Westberg, Johanna January 2016 (has links)
Bakgrund: Prostatacancer är den vanligaste cancerformen som drabbar män i Sverige. Sjukdomen skapar olika besvär som påverkar männens dagliga liv. Under sjukdomsförloppet upplever männen att de förlorar sin värdighet. Som sjuksköterska är det viktigt att se till hela patienten och ge en personcentrerad omvårdnad utifrån omvårdnadsdiagnoser. Syfte: Att belysa mäns upplevelse av att leva med prostatacancer. Metod: Litteraturstudie med kvalitativ design. Data hämtades från 12 vetenskapliga artiklar. Resultat: Studien utmynnade i fem kategorier som männen upplevde: informationsbehov, förlorad värdighet, oro för egen dödlighet, upplevelse av olika stöd och anpassning av vardagen. Slutsats: Männens vardag påverkas av sjukdomen prostatacancer och de behöver stöd i olika former. Sjuksköterskan bör möta männen på deras nivå och ge männen en individanpassad omvårdnad. / Background: Prostate cancer is the most common form of cancer that afflicts men in Sweden. The affliction creates different struggles that affect the men’s daily lives. During the progress of the disease the men experience a loss of their dignity. As a nurse it is important to care for the patient as a whole and provide a personal care, related to the nursing diagnosis of the patient. Aim: To shed light on the experiences of the men who are currently living with prostate cancer. Method: A study of literature focusing on qualitative data. Data was gathered from 12 scientific articles. Result: The study led to five categories that the men experienced: The lack of information, loss of dignity, anxiety surrounding own mortality, experience of different support forms and adjustment of the everyday life. Conclusion: The men’s daily lives are affected extensively by the disease prostate cancer and they need different forms of support. The nurse should level with the men in order to provide an individual care.
466

Combination Therapeutic Strategies Targeting Growth and Metabolic Pathways in Prostate Cancer

Canatsey, Ryan Douglas January 2016 (has links)
Despite recent advances, prognosis in metastatic prostate cancer remains poor. As with other cancers, tumor heterogeneity is an increasingly evident contributor in prostate tumorigenesis and developed resistance. Using in vitro and in vivo model systems, we examined novel diagnostic and therapeutic strategies in prostate cancer. In these studies, combination treatment with amuvatinib, a receptor tyrosine kinase inhibitor, and erlotinib, an epidermal growth factor inhibitor, was assessed for its ability to differentially modulate growth signaling in pathway diverse LNCaP (PTEN⁻) and DU-145 (PTEN⁺) human prostate cancer cell and mouse xenograft models. Our results suggest both individual mechanistic signaling activities, as well as benefits of the combination therapy though modulations of MAPK (pERK) and 4EBP1/cyclin D1 in growth signaling divergent PTEN+ and PTEN- prostate cancer cells. Additionally, despite the importance preanalytical tissue preservation on downstream diagnostic assays, exact protocols are not well defined and highly variable clinically and, as such, critical diagnostic information is lost. We show that a novel 2+2 fixation method induces target- and cell-specific alterations in immunostain intensity and efficacy. Importantly, cyclin D1 is increasingly utilized for as a clinical prognostic/diagnostic marker and demonstrated improved immunohistochemical staining efficacy with 2+2 fixation compared with treatment-matched xenograft protein alterations as assessed by western analysis. Finally, pentoxifylline (PTX) is a clinically utilized and well tolerated PDE inhibitor that has shown promise as a radio-/chemo-sensitization and anti-cancer agent against a variety of cancers. In these studies, we demonstrate that PTX induces cell and tumor growth inhibition in LNCaP prostate cancer cells. Mechanistically, PTX induces transient cellular signaling modulations of both the AMPK metabolic and AKT/mTOR growth pathways, while inducing autophagy. Also, PTX sensitizes LNCaP prostate cancer to cytotoxicity induced by first line chemotherapy docetaxel, inducing significant cellular apoptosis and reducing effective docetaxel concentrations by >10 fold for equivalent toxicity in viability assays. These findings nominate PTX as an adjunct therapy for the treatment of prostate cancer. In summary, these studies characterize the targeted signaling modulation by combination erlotinib and amuvatinib therapy, as well as pentoxifylline, for their use as therapies for prostate cancer. A novel fixation protocol was also assessed for improved diagnostic tissue preservation of critical signaling proteins. Further understanding in these areas will aid and expand the development of effective diagnostics, as well as emphasize the benefits of these and similar therapeutics for the treatment of prostate cancer.
467

Thermodynamics and Kinetics of the Three-Way Junction of Phi29 Motor pRNA and its Assembly into Nanoparticles for Therapeutic Delivery to Prostate Cancer

Binzel, Daniel W. 01 January 2016 (has links)
The emerging field of RNA nanotechnology necessitates creation of functional RNA nanoparticles, but has been limited by particle instability. Previously, it was found the three-way junction (3WJ) of the Phi29 DNA packaging motor pRNA was found to be ultra-stable and assemble in solution without the presence of metal ions. The three-way junction is composed of three short oligo RNA strands and proven to be thermodynamically stable. Here the assembly mechanism, thermodynamic and enzymatic stabilities, and kinetics are examined in order to understand the stability behind this unique motif. Thermodynamic and kinetics studies found that the pRNA 3WJ formed out of three components at a rapid rate creating a single-step three component collision with a lack of dimer intermediate formation while being governed by entropy, instead of the commonly seen enthalpy. Furthermore, the pRNA 3WJ proved to be stable at temperatures above 50 °C, concentrations below 100 pM, and produced a free energy of formation well below other studied RNA structures and motifs. With the high stability and folding efficiency of the pRNA 3WJ, it serves as an ideal platform for multi-branched RNA nanoparticles constructed through bottom-up techniques. RNA nanoparticles were constructed for the specific targeting of prostate cancer cells expressing Prostate Specific Membrane Antigen (PSMA) by receptor mediated endocytosis through the addition of an RNA aptamer; and the delivery of anti-miRNA sequences for gene regulation. The resulting nanoparticles remained stable while showing highly specific binding and entry in PSMA positive cells through cell surface receptor endocytosis. Furthermore, the entry of the nanoparticles allowed for the knockdown of against onco-miRNAs. Nanoparticles harboring antimiRNAs led to the upregulation of tumor suppressor genes, and signaling of apoptotic pathways. These findings display RNA nanotechnology can result in the production of stable nanoparticles and result in the specific treatment of cancers, specifically prostate cancer.
468

I nöd och lust : Sexuell lust ett år efter radikal prostatektomi: skillnader mellan män med och utan urininkontinens / Sexual desire after radical prostatectomy: differences between men with, and without urinary incontinence

Olofsson, Erika, Resolut, Caroline January 2015 (has links)
BAKGRUND: Prostatacancer (PCa) är den vanligaste cancerformen bland män i Sverige. Efter kirurgisk behandling, radikal prostatektomi (RP), drabbas många av urininkontinens och sexuella besvär. Studier på kvinnor visar att urininkontinens påverkar sexuell lust men det finns få liknande studier bland män. SYFTE: Syftet med studien är att jämföra självskattad sexuell lust bland män med och utan inkontinens, ett år efter RP. METOD: Denna kvantitativa tvärsnittstudie utgår från enkätmaterial insamlat i en pågående prospektiv studie. Data insamlat bland 1751 män, ett år efter RP, har analyserats och jämförts mellan två grupper (fall-kontrollstudie). RESULTAT: Resultatet visar att män med urininkontinens skattar lägre sexuell lust, ett år efter RP, än män utan urininkontinens samt att de i högre grad beskriver tanken på ett fortsatt liv med sina sexualproblem med negativa begrepp. KONKLUSION: Män som genomgått RP, och i synnerhet de som har urininkontinens, har nedsättningar i sexuallivet. Sjuksköterskan bör uppmärksamma och ge tid till samtal om påverkan på sexuallivet efter RP, med både patient och partner. Ökad kunskap inom området bidrar till ökad förståelse, och behövs för att sjuksköterskor ska kunna hjälpa dessa patienter. Nedsatt sexuell lust hos män är ett outforskat område och vidare forskning behövs. / BACKGROUND: Prostate cancer (PCa) is the most common form of cancer among Swedish men. Urinary incontinence and sexual dysfunction are two side effects that many men experience after surgery, radical prostatectomy (RP). Previous studies show that urinary incontinence has negative effects on women’s sexual desire. Few similar studies concern men. AIM: The aim of the study is to compare self-reported sexual desire among men with and without urinary incontinence, one year post-surgical treatment (RP). METHOD: This quantitative, cross-sectional study is based on a self-reported survey from an ongoing prospective study. Data collected from 1751 men, one year post-treatment, have been analyzed and compared between two groups (case-control study). RESULT: The result shows that men with urinary incontinence after RP have less sexual desire than men without urinary incontinence. These men are also less satisfied with the idea of spending the rest of their lives with their sexual problems. CONCLUSION: Men that have undergone RP, especially the ones who have urinary incontinence, experience sexual dysfunction. Nurses need to acknowledge and initiate dialogues with patients and their partners about effects on sexual life after RP. Research concerning men’s sexual desire will help nurses’ knowledge and ability to discuss sexual problems. More studies about men’s reduced sexual desire are necessary.
469

The Contribution of Inflammatory Cells to the Progression of Prostate Cancer

Jones, Kia J 16 May 2016 (has links)
In recent years, the causal relationship between inflammation and cancer has gained wider acknowledgement and acceptance. While various types of immune cells are involved in the process of inflammation, macrophages represent the major inflammatory component of many tumors. Derived from circulating monocytes, these cells migrate to tumor sites in response to molecular cues present within the tumor microenvironment. Once there, interactions with neoplastic cells shape the differentiation and functional orientation of macrophages into two phenotypically distinct subsets: the “classically” activated M1 macrophages and the “alternatively” activated M2 macrophages. The preeminent paradigm in macrophage-related cancer research is that within the tumor stoma, macrophages acquire an M2 phenotype characterized by production of pro-angiogenic factors, ECM degrading enzymes and up-regulation of anti-inflammatory responses, thereby promoting tumor progression. M1 macrophages, on the other hand are thought to exert anti-tumorigenic effects due to their production of pro-inflammatory cytokines, and reactive oxygen species (ROS). While the generation of ROS during immune responses is an important aspect of immune regulation and host defense, excessive ROS production has been implicated in the pathogenesis of various degenerative diseases, including cancer. Yet, despite the well-established role of M1 macrophages in generating high levels of ROS via NADPH oxidase (NOX), M1 macrophages are still largely viewed as anti-tumorigenic. Hence, this study reevaluates the complex interaction between prostate cancer (PCa) cells and tumor-associated macrophages (TAMs), and operates on the premise that PCa cells promote a pro-tumor microenvironment, denoted by increased inflammation and oxidative stress, in part, through M1 macrophage-mediated, NOX-derived ROS production. Accordingly, immunofluorescent analysis of prostate tissue microarrays demonstrated an influx of M1 macrophages in prostate carcinoma. Immature monocytes co-cultured with the poorly tumorigenic prostate cell line, LNCaP, demonstrated changes in morphology and protein expression consistent with M1 macrophage polarization. PCa cells co-cultured with M1 macrophages displayed significantly higher intracellular ROS levels. Furthermore, M1-mediated ROS generation through NOXs increased prostate cell invasiveness and anchorage-independent growth. Taken together, results from this study suggest a potentially novel pro-tumorigenic function of M1 macrophages in early PCa progression, and aid in understanding the complex role of inflammation in cancer.
470

Σχεδιασμός και σύνθεση νέων αμινο-στεροειδών

Τσαγκατάκη, Ειρήνη 02 April 2014 (has links)
Ο καρκίνος του προστάτη, αποτελεί ένα από τα σπουδαιότερα προβλήματα υγείας και συγκεκριμένα την τρίτη πιο συχνή αιτία θανάτου από καρκίνο στους άνδρες. Ο υποδοχέας ανδρογόνων είναι ένας σημαντικός μοριακός στόχος στη θεραπευτική αντιμετώπιση του καρκίνου του προστάτη. Η επιβίωση και ο πολλαπλασιασμός των καρκινικών προστατικών κυττάρων εξαρτώνται από τη δράση των ανδρογόνων, τουλάχιστον κατά τα πρώιμα στάδια της νόσου. Λόγω αυτής της εξάρτησης, η αποστέρηση των ανδρογόνων αποτελεί την αρχική μέθοδο φαρμακολογικής παρέμβασης για την αντιμετώπιση του καρκίνου του προστάτη. Ωστόσο, παρά την αρχική αποτελεσματικότητα αυτής της προσέγγισης στην καταστολή του όγκου, εκείνος επανακάμπτει εντός δύο ή τριών ετών και εξακολουθεί να αναπτύσσεται ανεξάρτητα από την ύπαρξη ανδρογόνων. Οι υπάρχουσες θεραπευτικές προσεγγίσεις αδυνατούν να προλάβουν την επανεμφάνιση του όγκου. Προς αυτήν την κατεύθυνση, η ανάπτυξη νέων θεραπευτικών παραγόντων με αποτελεσματικότερη αντιανδρογόνο δράση, θα είχε σημαντική αξία στη θεραπεία του καρκίνου του προστάτη. Πρόσφατα, στεροειδικά παράγωγα, τα οποία έφεραν έναν εξαμελή λακταμικό δακτύλιο στη θέση-20 του στεροειδικού σκελετού εμφάνισαν ανασταλτική δράση έναντι του ανδρογονικού υποδοχέα καθώς και έναντι του πολλαπλασιασμού καρκινικών προστατικών κυττάρων. Επίσης, παράλληλες μελέτες της ερευνητικής ομάδας μας έχουν δείξει ότι τροποποιημένα στεροειδικά παράγωγα που έφεραν είτε ενδοκυκλική λακταμική ή εξωκυκλική αμιδική -NHCO- ομάδα, έχουν εμφανίσει εξαιρετική δράση έναντι αιματολογικών νεοπλασιών. Με βάση τα παραπάνω δεδομένα, στα πλαίσια της παρούσας μελέτης πραγματοποιήθηκε ο σχεδιασμός και η σύνθεση νέων 20-αμινοστεροειδών. Συγκεκριμένα επιτεύχθηκε η σύνθεση νέων μορίων που φέρουν ως κύρια δομικά χαρακτηριστικά έναν επταμελή λακταμικό Α-στεροειδικό δακτύλιο και ένα αμινο-υποκατεστημένο στερεογονικό κέντρο (C-20). Το συνθετικό σχήμα που ακολουθήθηκε, περιελάμβανε αρχικά τη διεύρυνση του Α-στεροειδικού δακτυλίου της πρεγνενολόνης μέσω μετάθεσης Beckmann της αντίστοιχης 3-κετοξίμης σε επταμελή λακταμικό δακτύλιο και μετέπειτα τη διαστερεοεκλεκτική μετατροπή της 20-κετο-ομάδας σε αμινο-υποκατεστημένο στερεογονικό κέντρο μέσω νουκλεόφιλης προσθήκης οργανομαγνησιακού αντιδραστηρίου στην αντίστοιχη ενδιάμεση Ν-[t-butyl-σουλφινυλ]-20-ιμίνη. Κατά την εξέλιξη της συνθετικής πορείας διερευνήθηκαν και βελτιστοποιήθηκαν οι πειραματικές συνθήκες των επιμέρους σταδίων. Η αποτίμηση της βιολογικής δράσης των νέων 20-αμινοστεροειδών αναμένεται να αποσαφηνίσει κατά πόσο οι παραπάνω δομικές τροποποιήσεις μπορούν να συμβάλλουν στην εκδήλωση αντιανδρογόνου και αντικαρκινικής δράσης. Παράλληλα, ο στεροειδικός σκελετός των νέων μορίων είναι εφικτό να οδηγήσει σε νέα τροποποιημένα παράγωγα για την εξαγωγή σχέσεων χημικής δομής-βιολογικής δραστικότητας. / Prostate cancer is one of the most important health problems and specifically the third most common cause of death because of cancer in men. The androgen receptor is an important molecular target for the treatment of prostate cancer. The survival and the proliferation of cancer prostatic cells depend on the action of androgens, at least at the early stages of the disease. Because of this dependency, androgen deprivation is the initial method in the pharmacological intervention for the treatment of prostate cancer. However, despite the initial effectiveness of this approach in tumor suppression, the tumor relapses within two or three years and continues to grow regardless the presence of androgens. The existing therapeutic approaches fail to prevent the revival of the tumor. Toward this direction, the development of new therapeutic agents with more effective antiandrogen activity, would have significant value in the treatment of prostate cancer. Recently, steroid derivatives, which carried a six membered lactam ring at C-20 of the steroid skeleton, exhibited inhibitory activity against the androgen receptor and also against the proliferation of prostate cancer cells. Furthermore, parallel studies of our research group have shown that modified steroid derivatives which carried either a lactam or an amide-NHCO-group, have shown excellent activity against haematological malignancies. Based on these data, in this study the design and synthesis of new 20-aminosteroid was achieved. Specifically we achieved the synthesis of new molecules bearing as main structural features one seven membered lactam A-steroid ring and an amino-substituted stereogenic center (C-20). The synthetic approach used, initially involved the pregnenolone A-steroidal ring expansion to a seven membered lactam ring via Beckmann rearrangement of the corresponding 3-ketoxime and then the diastereoselective conversion of the 20-keto group to an amino-substituted stereogenic center via nucleophilic addition of organometallic reagent to the corresponding intermediate N-[t-butyl-sulfinyl]-20-imine. During this process, the experimental conditions of the intermediate synthetic steps were investigated and optimized. The biological evaluation of the new 20-aminosteroids is expected to unravel whether these structural modifications may contribute to antiandrogenic and anticancer activity. Meanwhile, the steroidal skeleton of the new molecules may lead to the development of new modified derivatives for further structure-activity relationship studies.

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