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Radiolabeled acetate PET in oncology imaging : studies on head and neck cancer, prostate cancer and normal distributionSun, Aijun January 2010 (has links)
The use of positron emission tomography (PET) for imaging in oncology has grown rapidly in recent years. 2-[18F]-fluorodeoxyglucose (FDG) is the most common tracer of PET, although drawbacks exist. Radiolabeled 1-[11C]-acetate (C-AC) is a simple probe for evaluation of perfusion, anabolism (lipogenesis) and catabolism (oxidative metabolism) in all living tissues. This study explored the potential of AC PET in head and neck cancer, benign and malignant lymph nodes in prostate cancer and normal distribution. In head and neck cancer, C-AC PET detected more primaries and lymph node metastases than FDG PET. The mean primary tumor volumes delineated by C-AC was 51% larger than that of FDG before radiotherapy (RT). Both FDG and C-AC PET tumor volumes must be carefully validated before used in clinical routine. Baseline tumor clearance rate (kmono) was higher in complete responders (CR) than that in partial responders (PR). kmono tended to correlate inversely with FDG SUV at baseline. Radiosensitive tumors might rely predominantly on oxidative metabolism for their biogenetic needs. kmono increased in PR during RT. The potential reversibility of impaired kmono in radioresistant tumors imply that treatment targeting the intermediary metabolism might improve the outcome. Tumor relative perfusion index (rF) and kmono were coupled in CR throughout the RT, but not in PR. Dynamic C-AC PET provides a new non-invasive method to simultaneously evaluate the tumor oxidative metabolism and perfusion which link the RT response in patients by a single tracer injection. In prostate cancer, elevated C-AC accumulation is common in benign inguinal lymph nodes, probably due to increased lipogenesis rather than lymphatic drainage. CT Hounsfield unit of benign nodes was lower than that of metastases, suggesting that density measurement using CT might improve the specificity of nodal staging of prostate cancer. A novel tracer 2-[18F]-fluoroacetate (F-AC) was synthesized and used for dynamic PET-CT imaging in animals. Compared with C-AC PET-CT, F-AC showed prolonged blood retention, no detectable trapping in myocardium and salivary glands, rapid excretion from liver to bile and urine and de-fluorination resulting in intensive skeletal activity. F-AC does not mimic the normal physiologic path of C-AC and appears to be of little use for assessment of perfusion, intermediary metabolism or lipogenesis.
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Avaluació dels efectes d'un programa d'exercici físic individualitzat sobre la Qualitat de Vida (QdV), la incontinència urinària, la fatiga i la resistència muscular amb malalts del càncer de pròstataSerdà Ferrer, Bernat-Carles 29 May 2009 (has links)
El cáncer de próstata es el cáncer más frecuente en los hombres en muchos países industrializados. Considerando el porcentaje de supervivencia relativa a los 5 años (76,5%) y el estado de morbilidad que generan los tratamientos vigentes, el concepto de Calidad de Vida (CdV) del hombre mayor con cáncer de próstata pasa a ser un objetivo prioritario en la intervención sociosanitaria. Clásicamente la evaluación del impacto que generan los síntomas se ha determinado por la frecuencia y el número de síntomas asociados a la enfermedad y al tratamiento. A nuestro parecer, lo más apropiado es realizar el análisis objetivando además el impacto que generan en la actividad de vida diaria de los afectados. Este artículo tiene un doble objetivo. Primero, evaluar los beneficios de un programa de ejercicio de fuerza adaptado a la enfermedad y al tratamiento de cáncer de próstata. Segundo, identificar los síntomas más relevantes del cáncer de próstata desde la perspectiva del paciente y el impacto que generan a la Calidad de Vida del hombre mayor. La propuesta metodológica se basa en la triangulación metodológica entre métodos secuencial, (cuantitativo y cualitativo). En los resultados se observa una mejora significativa de la Calidad de Vida del enfermo, mediado indirectamente por la mejora del síntoma de incontinencia y el dolor. Así mismo se observa una mejora de la capacidad de la fuerza y resistencia muscular más evidente en las extremidades inferiores. Queda científicamente demostrada la eficacia de un programa de ejercicio físico de fuerza adaptado a los síntomas que genera la enfermedad y el tratamiento de cáncer de próstata en la mejora de la Calidad de Vida de la persona mayor. / Prostate cancer is the most frequent cancer in men in many industrialized countries. Considering the percentage of relative survival 5 years (76,5%) and the state of morbidity generate by treatments, the quality of life of the older man with cancer of prostate is a priority objective in the public health intervention. The evaluation of the impact generated by symptoms has been determined by the frequency and the number of associated symptoms to illness and treatment. In our pinion it would be more appropriated to carry out the analysis objectifying also the impact generated in older men every day life activity.This article has a double objective. First, to evaluate the benefits of an adapted force exercise program to the illness and to the prostate cancer treatment. Second, to identify the most prominent symptoms of prostate cancer from the perspective of the patient and the impact that generate to their Quality of Life.The methodological proposal is based on the methodological sequential triangulation among methods, (quantitative and qualitative).Results show a significant improvement of the Quality of Life of the patients, indirectly mediated by the improvement of incontinence and pain symptoms. Also, an improvement of the capacity of the force and resistance is observed, more evident in lower extremities. It remains scientifically demonstrated the efficacy in the improvement of the Quality of Life of the adult of a physical exercise of force program adapted to the symptoms generated by the illness and the prostate cancer treatment.
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Investigating the Role of Deoxyhypusine Synthase in the Invasiveness of PC3 Cells Using siRNAAdam, Eva January 2008 (has links)
Deoxyhypusine synthase (DHS) catalyzes the first step in the hypusination of eukaryotic translation initiation factor 5A (eIF5A). In human cells, two eIF5A isoforms are present, eIF5A-1 and eIF5A-2, and DHS catalyzes the hypusination of both. Since both eIF5As are substrates for DHS, the biological functions of DHS are likely to be exerted through the various post-translational forms of these two eIF5As. The lysine form of eIF5A-1 has been associated with apoptosis, while the hypusinated form of eIF5A-1 has been associated with cell viability and proliferation. eIF5A-2 has been found to be over-expressed in certain cancers and has been proposed to function as an oncogene. Dhs is also over-expressed in certain human cancers and is a metastatic signature gene.
The purpose of the present study was to investigate the role of DHS in cancer cell invasiveness, cell proliferation, and apoptosis using RNA interference. The main finding of the study is that DHS siRNA treatment decreases invasiveness of PC3 cells in vitro. Both DHS 0 siRNA treatment and DHS 1/b siRNA treatment significantly reduced cell invasiveness of PC3 cells as measured by the Matrigel invasion assay. Potential confounding variables, such as differences in cell proliferation or differences in apoptosis in response to DHS siRNA treatment, were assessed using the XTT cell proliferation assay and the Annexin V/Pi apoptosis assay, and they were found not to have an effect. In the absence of serum, DHS siRNA treatment did not result in significant decrease in cell proliferation compared to the control siRNA treatment. Furthermore, DHS siRNA treatment did not induce apoptosis in PC3 cells under the present experimental conditions. In conclusion, depletion of DHS with RNAi reduces invasiveness, but does not induce apoptosis in PC3 cells. The significance of the research is that the anti-invasiveness effect of DHS depletion in metastatic cancer cells is shown for the first time in the present study. Thus, DHS depletion may be useful to combat cancer in conjunction with L-eIF5A-1 over-expression.
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The Role of Rankl in Prostate Cancer Progression and Bone MetastasisChu, Chia-Yi 06 December 2011 (has links)
This study focused on the role of RANKL in prostate cancer EMT progression and metastasis. Activation of RANK, a receptor activator of NF-kB, by its ligand RANKL, in a paracrine manner is responsible for osteoclast differentiation and bone remodeling. RANK activation in cancer cells, however, is thought to be promoted by both autocrine and paracrine mechanisms because RANKL has been shown to be derived from either tumor or its microenvironment, such as osteoblasts, infiltrating inflammatory cells and stromal fibroblasts. In the present study, we demonstrated that autocrine and paracrine RANKL-RANK signaling could be responsible for driving prostate cancer bone metastasis by promoting epithelial to mesenchymal transition (EMT). We further characterized a novel converging RANKL-c-Met signaling network in which the activation of RANKL was found to promote the expression of both RANKL and c-Met in an autocrine manner in prostate cancer cells. The induced RANKL and c-Met in prostate cancer cells is biologically functional and contributes to increased osteoclastogenesis, epithelial to mesenchymal transition (EMT), cell motility, migration and invasion and conferred bone and soft tissue metastases. Remarkably, RANKL expression by 1,000 prostate cancer cells can provoke bone and soft tissue metastases of a “dormant” population of prostate cancer cells which by themselves failed to form tumors and colonize mouse skeleton, suggesting RANKL can serve as a factor in “reawakening” cancer dormancy to initiate the re-growth and metastasis of cancer cells. We also showed that RANKL-induced RANKL feed-forward autocrine regulation is mediated through cMyc transactivation, allowing the establishment of a “vicious cycle” further promoting prostate cancer growth and metastasis. The converging RANKL-c-Met signaling network is therefore a novel target that could be further manipulated for delaying the lethal progression of castration-resistant human prostate cancer bone metastasis.
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Investigating the Role of Deoxyhypusine Synthase in the Invasiveness of PC3 Cells Using siRNAAdam, Eva January 2008 (has links)
Deoxyhypusine synthase (DHS) catalyzes the first step in the hypusination of eukaryotic translation initiation factor 5A (eIF5A). In human cells, two eIF5A isoforms are present, eIF5A-1 and eIF5A-2, and DHS catalyzes the hypusination of both. Since both eIF5As are substrates for DHS, the biological functions of DHS are likely to be exerted through the various post-translational forms of these two eIF5As. The lysine form of eIF5A-1 has been associated with apoptosis, while the hypusinated form of eIF5A-1 has been associated with cell viability and proliferation. eIF5A-2 has been found to be over-expressed in certain cancers and has been proposed to function as an oncogene. Dhs is also over-expressed in certain human cancers and is a metastatic signature gene.
The purpose of the present study was to investigate the role of DHS in cancer cell invasiveness, cell proliferation, and apoptosis using RNA interference. The main finding of the study is that DHS siRNA treatment decreases invasiveness of PC3 cells in vitro. Both DHS 0 siRNA treatment and DHS 1/b siRNA treatment significantly reduced cell invasiveness of PC3 cells as measured by the Matrigel invasion assay. Potential confounding variables, such as differences in cell proliferation or differences in apoptosis in response to DHS siRNA treatment, were assessed using the XTT cell proliferation assay and the Annexin V/Pi apoptosis assay, and they were found not to have an effect. In the absence of serum, DHS siRNA treatment did not result in significant decrease in cell proliferation compared to the control siRNA treatment. Furthermore, DHS siRNA treatment did not induce apoptosis in PC3 cells under the present experimental conditions. In conclusion, depletion of DHS with RNAi reduces invasiveness, but does not induce apoptosis in PC3 cells. The significance of the research is that the anti-invasiveness effect of DHS depletion in metastatic cancer cells is shown for the first time in the present study. Thus, DHS depletion may be useful to combat cancer in conjunction with L-eIF5A-1 over-expression.
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1,25(OH)2D3 increase caspase-3 activity in LNCaP cells after 2 minutes and 48h separatelyKjellerås, Jennifer January 2007 (has links)
<p>Cancer or malignant tumors has a high death frequency in many countries. Nowadays many research facilities are dedicated to find new substances and techniques which would lead to better cancer therapies. Seven years ago a research team from Finland made a remarkable connection between vitamin D deficiencies and an increased chance of getting prostate cancer. The research investigating this statement has lead to findings of a new non-classical effect of the calcium controlling vitamin, 1,25(OH)2D3. This effect involves anti-proliferatory effects and more importantly apoptotic effects resulting in the hope of finding a new drug that can cure prostate cancer with the smallest amount of harm to the body.</p><p>In an attempt to find out if the signalling pathway of this apoptotic effect is fast or slow, an experiment designed to detect when the apoptotic protein caspase-3 is induced has been performed. Cells from the cell line LNCaP has been cultured and incubated with 1,25(OH)2D3 and after 0min - 48h an assay was performed to detect the relative amounts of caspase-3 present in every sample. The optimal time period (48h) was then subjected to three different concentrations of 1,25(OH)2D3 and read in the same way as the previous samples. The results showed an increase in caspase-3 expression as early as 2 min, but disappear to be seen again at 24h and are more profound in 48h samples. The caspase-3 expression was also seen to form a possible exponential curve in dose-response.</p>
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Einfluss des Insulin-ähnlichen Wachstumsfaktors I auf die Androgenrezeptor-Signaltransduktion in ProstatakrebszellenSchmidt, Siw 18 November 2007 (has links) (PDF)
Die im Rahmen dieser Arbeit durchgeführten Untersuchungen zum Einfluss der Wachstumsfaktoren IGF-I, EGF und dem Zytokin IL-6 auf den Androgenrezeptor-Signalweg zeigten in verschiedenen Prostatakarzinom-zelllinien schon nach zwei Stunden eine deutliche Degradation des Androgenrezeptor-Proteins. Die ausschließlich auf Protein-Ebene stattfindende, Wachstumsfaktor-induzierte negative Regulation des Androgenrezeptors konnte durch einen schnellen Androgeneffekt wieder aufgehoben werden. Mittels Luziferase-Reportergen-Assays wurde kein Einfluss der Wachstums-faktorwirkung auf die transkriptionelle Aktivität des Androgenrezeptors nachgewiesen. Darüber hinaus konnte eine signifikant reprimierende Wirkung durch IGF-I und EGF in Kombination mit geringen Mengen DHT beobachtet werden. Weitere Resultate dieser Arbeit deuten auf einen, durch den PI3-Kinase-Signalweg vermittelten, proteasomalen Abbauprozess des Rezeptors hin. Da die Suppression der downstream gelegenen Proteinkinase Akt keine Veränderung hinsichtlich der Degradation aufwies, konzentrierte sich die weiterführende Arbeit auf eine mögliche direkte Regulation des Androgen-rezeptors durch die PI3-Kinase. Unter Verwendung von rekombinanten GST-Fusionsproteinen konnte in Interaktionsstudien unter in vitro Bedingungen eine Phosphotyrosin-unabhängige Bindung zwischen der C-SH2-Domäne der p85-Untereinheit der PI3-Kinase und dem N- und C-Terminus des Androgenrezeptors nachgewiesen werden. Durch die nähere Charakterisierung dieser Bindungsbereiche mit Hilfe von Peptidarrays und anschließenden Alanin-Substitutionen war es möglich, für den N-Terminus 18, für den C-Terminus des Androgenrezeptors 6 und für die p85-C-SH2-Domäne der PI3-Kinase 11 Aminosäuren zu identifizieren. Die durch gezielte Punktmutagenese an diesen Aminosäurepositionen hergestellten Androgenrezeptor-Einzel- und -Mehrfachmutanten wiesen in Bindungsstudien dennoch Interaktion zur PI3-Kinase auf. Eine von Anderson und Kollegen postulierte Phosphotyrosin-unabhängige Bindung der SH2-Domänen der p85-Untereinheit der PI3-Kinase durch sogenannte „basic-X-basic“-Motive wurde ebenfalls in Interaktionstests zwischen der PI3-Kinase und dem Androgenrezeptor überprüft. Aufgrund der Tatsache, dass einige der identifizierten Aminosäuren auf dem Androgenrezeptor Teil eines „basic-X-basic“-Bindungsmotives sind, wurden Kombinationsmutanten generiert, die sowohl im N-Terminus als auch im CTerminus des Androgenrezeptors ein bzw. zwei zerstörte „basic-X-basic“-Motive enthielten. Untersuchungen zum Bindungsverhalten dieser Mutanten zeigten zwar weiterhin Interaktion zur p85-C-SH2-Domäne der PI3-Kinase, jedoch der durch Western-blot-Analyse überprüfte IGF-I-induzierte Degradationseffekt des Androgenrezeptor-Proteins konnte mit zwei der verwendeten Androgenrezeptor-Kombinationsmutanten nicht mehr beobachtet werden.
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Identification of Prostate Cancer Metabolomic Markers by 1H HRMAS NMR Spectroscopy and Quantitative ImmunohistochemistryLöbel, Franziska 23 September 2015 (has links) (PDF)
Background
Prostate cancer (PCa) is the most frequently diagnosed malignant disease among adult males in the USA and the second leading cause of cancer deaths in men. Due to the lack of diagnostic tools that are able to differentiate highly malignant and aggressive cases from indolent tumors, overtreatment has become very common in the era of prostate specific antigen (PSA) screening. New diagnostic methods to determine biological status, malignancy, aggressiveness and extent of PCa are urgently needed. 1H High Resolution Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy (1H HRMAS MRS) can be used to establish PCa metabolomic profiles while preserving tissue architecture for subsequent histopathological analysis. Immunohistochemistry (IHC), as opposed to conventional histopathology methods, has the potential to provide objective, more accurate and quantitative knowledge of tissue pathology. This diagnostic- accuracy study sought to evaluate a novel approach to quantitatively identify metabolomic markers of PCa by exploring the potential of PCa immunomarkers to quantify metabolomic profiles established by 1H HRMAS MRS.
Material and Methods
1H HRMAS MRS was performed on tissue samples of 51 prostate cancer patients using a 14.1 Tesla NMR spectrometer (BRUKER Biospin, Billerica, MA) with a rotor synchronized CPMG pulse sequence. Spectral intensities of 36 regions of interest were measured as integrals of curve fittings with Lorentzian-Gaussian line shapes. Immunohistochemistry (IHC) was carried out following the spectroscopy scan, using three prostate immunomarkers to identify cancerous and benign glands: P504S (Alpha-methylacyl-CoA-racemace), CK903 (high-molecular weight cytokeratin) and p63. The immunostaining quality following 1H HRMAS MRS was evaluated and compared to unscanned sections of the same sample, to verify the stability and accessibility of the proposed immunomarkers. IHC images were automatically and quantitatively evaluated, using a quantitative image analysis program (QIAP), to determine the percentage of cancerous and benign epithelia in the tissue cross- sections. The results of the program were validated by a correlation with the results of a quantitative IHC review and quantitative conventional histopathology analysis performed by an experienced pathologist. Ultimately, spectral intensities and the cancer epithelium percentage, obtained from quantitative immunohistochemistry, were correlated in order to validate PCa metabolomic markers identified by 1H HRMAS MRS.
Patient outcomes and incidence of recurrence were determined by retrospective review of medical records five years after initial surgery. Categories of recurrence were correlated to spectral intensities to explore potential metabolomic markers of recurrence in the cohort.
Results
Immunostainings with P504S and CK903 showed excellent staining quality and accessibility following 1H HRMAS MRS, suggesting these markers to be suitable for the presented quantitative approach to determine metabolomics profiles of PCa. In contrast, the quality of p63 IHC was impaired after previously performed spectroscopy.
IHC using the immunomarkers P504S and CK903 on adjacent slides was found to present a feasible quantitative diagnostic method to distinguish between benign and cancerous conditions in prostate tissue. The cancer epithelium percentage as determined by QIAP showed a significant correlation to the results of quantitative IHC analysis performed by a pathologist (p < 0.001), as well as to a quantitative conventional histopathology review (p = 0.001). The same was true for the benign epithelium percentage (p < 0.001 and p = 0.0183), validating the presented approach.
Two metabolomic regions showed a significant correlation between relative spectral intensities and the cancer epithelium percentage as determined by QIAP: 3.22 ppm (p = 0.015) and 2.68 ppm (p = 0.0144). The metabolites corresponding to these regions, phosphocholine and citrate, could be identified as metabolomic markers of PCa in the present cohort.
45 patients were followed for more than 12 months. Of these, 97.8% were still alive five years after initial surgery. 11 patients (24.4%) experienced a recurrence during the follow- up time. The categories of recurrence showed a correlation to the spectral intensities of two regions, 2.33 – 2.3 ppm (p = 0.0403) and 1.28 ppm (p = 0.0144), corresponding to the metabolites phosphocreatine and lipids.
Conclusion
This study introduces a method that allows an observer-independent, quantitative analysis of IHC to help establish metabolomic profiles and identify metabolomic markers of PCa from spectral intensities obtained with 1H HRMAS NMR Spectroscopy. The immunomarkers P504S and CK903 have been found suitable IHC analysis following 1H HRMAS MRS. A prospective in vivo application of PCa metabolite profiles and metabolomic markers determined by the presented method could serve as highly sensitive, non- invasive diagnostic tool. This observer- independent, computer- automated, quantitative analysis could help to distinguish highly aggressive tumors from low-malignant conditions, avoid overtreatment and reduce risks and complications for cancer patients in the future. Further studies are needed to verify the identified PCa metabolomic markers and to establish clinical applicability. / Einführung
Prostatakrebs ist eine häufigsten Krebserkrankungen in den USA und die zweithäufigste malignom- assoziierte Todesursache männlicher Patienten weltweit. Seit der Einführung des Prostata- spezifischen Antigen (PSA)- Screeningtests wird diese Krebsart in früheren Stadien diagnostiziert und therapiert, wodurch die Mortalitätsrate in den letzten Jahren deutlich
reduziert werden konnte. Da moderne diagnostische Methoden bislang jedoch nicht ausreichend in der Lage sind, suffizient zwischen hochmalignen und weniger aggressiven Varianten dieses bösartigen Krebsleidens zu unterscheiden, werden häufig auch Patienten aggressiv therapiert, deren niedriggradiges Prostatakarzinom keine klinische Relevanz gehabt hätte. Es besteht daher ein großes wissenschaftliches Interesse an der Entwicklung neuer diagnostischer Methoden zur akkuraten Bestimmung von biologischem Status, Malignität, Aggressivität und Ausmaß einer Prostatakrebserkrankung.
\\\\\\\"1H High Resolution Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy\\\\\\\" (1H HRMAS MRS) ist eine vielversprechende diagnostische Methode, welche es ermöglicht, metabolomische Profile von Prostatakrebs zu erstellen, ohne die Gewebsstruktur der analysierten Proben zu zerstören. Durch anschließende histopathologische Begutachtung lassen sich die erstellten Metabolitprofile validieren und evaluieren. Im Gegensatz zu konventionellen histopathologischen Methoden können durch
immunhistochemische Verfahren dabei objektivere, akkuratere und quantifizierbare histopathologische Erkenntnisse gewonnen werden.
Die vorliegende Studie präsentiert einen neuentwickelten diagnostischen Ansatz zur quantitativen Bestimmung von metabolomischen Markern von Prostatakrebs, basierend auf der Durchführung von 1H HRMAS NMR Spektroskopie und quantitativer Immunhistochemie.
Material und Methoden
Einundfünfzig Gewebsproben von Prostatakrebspatienten wurden mittels 1H HRMAS MRS an einem 14.1 T BRUKER NMR Spektrometer unter Einsatz einer CPMG-Pulssequenz untersucht. Spektrale Intensitäten in 36 Metabolitregionen wurden gemessen. Anschließend wurden die analysierten Gewebeproben mit drei Immunfärbemarkern für sowohl malignes
(P504S, Alpha-methylacyl-CoA-racemase) als auch benignes (CK903, High-molecular weight cytokeratin, und p63) Prostatagewebe angefärbt und quantitativ mit Hilfe eines Bildanalyseprogramms (QIAP) ausgewertet. Die Anwendbarkeit und Auswertbarkeit der genannten Immunomarker nach Spektroskopie wurde evaluiert und mit der Färbungsqualität
von nicht- gescannten Schnitten verglichen.
Die Resultate der automatischen Auswertung durch QIAP konnten durch einen erfahrenen Pathologen in einer quantitativen Analyse der Immunfärbungen sowie konventioneller histologischer Färbungen derselben Gewebsproben validiert werden. Die spektralen Intensitäten aus den Messungen mit 1H HRMAS MRS wurden mit den korrespondierenden
Ergebnissen der quantitativen Auswertung der Immunfärbungen korreliert, um metabolomische Marker von Prostatakrebs zu identifizieren.
Der klinische Verlauf und die Rezidivrate der Patienten wurden 5 Jahre nach der initialen Prostatektomie retrospektiv bestimmt. Rezidivkategorien wurden erstellt und mit den bestimmten spektralen Intensitäten korreliert, um metabolomische Marker für das Auftreten von Prostatakrebsrezidiven zu identifizieren.
Ergebnisse
Die Immunfärbungen mit P504S und CK903 zeigten exzellente Qualität und Auswertbarkeit nach vorheriger 1H HRMAS MRS. Beide Marker eigneten sich zur Durchführung von quantitativer Immunhistochemie an spektroskopierten Gewebeproben. Im Gegensatz dazu war die Qualität der Immunfärbungen mit p63 nach Spektroskopie vermindert. Quantitative
Immunfärbungen unter Einsatz der Immunmarker P504S und CK903 stellten eine praktikable diagnostische Methode dar, um zwischen malignen und benignem Prostatagewebe zu unterscheiden.
Der Anteil von bösartig verändertem Prostatagewebe, bestimmt durch QIAP, korrelierte signifikant mit den Ergebnissen der quantitativen Analyse der Immunfärbungen durch den Pathologen (p < 0.001), sowie mit der quantitativen Auswertung der konventionellen histopathologischen Färbung (p = 0.001). Ebenso ließ sich die Bestimmung des Anteils von
benignem Gewebe mit QIAP zu den Ergebnissen der pathologischen Analyse korrelieren (p < 0.001 und p = 0.0183).
Für zwei metabolomische Regionen konnte ein signifikante Korrelation zwischen relativen spektralen Intensitäten, bestimmt mit 1H HRMAS NMR Spektroskopie, und dem Anteil von malignem Epithelium in derselben Gewebeprobe, ermittelt durch QIAP, festgestellt werden: 3.22 ppm (p = 0.015) und 2.68 ppm (p = 0.0144). Die zu diesen Regionen korrespondierenden Metaboliten, Phosphocholin und Zitrat, konnten als potentielle metabolomische Marker für Prostatakrebs identifiziert werden.
Die retrospektiven Analyse der klinischen Daten der Patienten fünf Jahre nach Prostatektomie ergab eine Überlebensrate von 97.8%. Elf dieser Patienten (24.4%) erlitten ein Rezidiv ihrer Erkrankung. Die bestimmten Rezidivkategorien korrelierten signifikant mit zwei metabolomischen Regionen (2.33 – 2.3 ppm, p = 0.0403 und 1.28 ppm, p = 0.0144), welche
zu den Metaboliten Phosphokreatin und Lipiden korrespondierten.
Schlussfolgerung
Die vorliegende Studie präsentiert einen diagnostischen Ansatz zur objektiven und quantitativen Bestimmung metabolomischer Marker von Prostatakrebs unter Verwendung von 1H HRMAS MRS und Immunhistochemie.
P504S und CK903 eignen sich als Immunmarker für quantitative Immunfärbungen nach vorheriger Durchführung von 1H HRMAS MRS.
Die Metaboliten Phosphocholin und Zitrat konnten in der vorliegenden Patientenkohorte als potentielle metabolomische Marker für Prostatakrebs identifiziert werden.
Eine mögliche in vivo Anwendung der gefundenen metabolomischen Marker könnte als hochsensitives, objektives und nicht- invasives diagnostisches Werkzeug der Prostatakrebsdiagnostik dienen. Der vorliegende untersucherunabhängige, automatisierte und quantitative diagnostischer Ansatz hat das Potential, zwischen hochmalignen und weniger
aggressiven Krebsfällen zu unterscheiden und somit unnötige Risiken und Komplikationen für Prostatakrebspatienten zu reduzieren.
Weitere Untersuchungen sind notwendig, um die identifizierten metabolomischen Marker zu verifizieren und eine klinische Anwendung zu etablieren.
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TRAF6, a key regulator of TGFβ-induced oncogenesis in prostate cancerSundar, Reshma January 2015 (has links)
Prostate cancer is the most common cancer in men, with the incidence rapidly increasing in Europe over the past two decades. Reliable biomarkers for prostate cancer are currently unavailable. Thus, there is an urgent need for improved biomarkers to diagnose prostate cancer at an early stage and to determine the best treatment options. Higher expression of transforming growth factor-β (TGFβ) has been reported in patients with aggressive cancer. TGFβ is a multifunctional cytokine that acts as a tumor suppressor during early tumor development, and as a tumor promoter at later stages of cancer. TGFβ signals through the canonical Smad or non-Smad cascade via TGFβ type II and type I receptors. The TGFβ signaling cascade is regulated by various post-translational modifications of its key components. The present investigation aimed to identify a potential function of TRAF6 in TGFβ-induced responses in prostate cancer. The first two articles of this thesis unveil the proteolytic cleavage of TGFβ type I receptor (TβRI), and the biological importance of the liberated TβRI intracellular domain (TβRI-ICD) in the nucleus. We found that tumor necrosis factor receptor-associated factor 6 (TRAF6) polyubiquitinates TβRI, which leads to cleavage of TβRI by tumor necrosis factor alpha converting enzyme (TACE) in a protein kinase C zeta (PKCζ)-dependent manner. Following ectodomain shedding, TβRI undergoes a second cleavage by presenilin 1 (PS1), which liberates TβRI-ICD. TβRI-ICD translocates to the nucleus, where it regulates its own expression as well as expression of the pro-invasive gene Snail1, thereby promoting invasion. We further found that TβRI-ICD associates with Notch intracellular domain (NICD) to drive expression of the pro-invasive gene Snail1, as well as Notch1 ligand Jag1. The third article provides evidence that TRAF6 promotes Lys63-linked polyubiquitination of TβRI at Lys178 in a TGFβ-dependent manner. TβRI polyubiquitination was found to be a prerequisite for TβRI nuclear translocation, and thus for regulation of the genes involved in cell cycle, differentiation, and invasion of prostate cancer cells. In the fourth article we investigated the role of the pro-invasive gene Snail1 in TGFβ-induced epithelial-to-mesenchymal transition (EMT) in prostate cancer cells.
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Adenovirus-mediated Gene Therapy of Prostate CancerDanielsson, Angelika January 2010 (has links)
Adenovirus-mediated gene therapy is a potential complement to standard cancer treatments. Advantages are that vectors can be used to target tumors and that replicating viruses lead to increased therapeutic dosage. In this thesis, an oncolytic serotype 5 adenovirus (Ad5), Ad[i/PPT-E1A, E3], was developed where viral replication is controlled by the insulator-shielded (i) prostate-specific PPT promoter. The adenoviral E3 region was inserted for its immune regulatory and lysis functions. Ad[i/PPT-E1A, E3] had improved cytotoxic abilities both in vitro and in a prostate cancer xenograft mouse model compared to a virus lacking the E3 region. To further improve adenoviral vectors, the histone deacetylase inhibitor (HDACi) FK228 was studied. FK228 has been proposed to enhance the effect of adenoviral therapy by upregulation of CAR, the primary receptor for Ad5 infection. In the present study, we observed that FK228 promotes transgene expression even better when administered after viral transduction, indicating a post-transductional enhancement of transgene expression. Another interesting finding was that FK228 reduced transgene expression from the PPT promoter in the prostate cancer cell line LNCaP. This is explained by the fact that different HDACi have the ability to provoke a neuroendocrine phenotype of LNCaP. A potential drawback with adenoviral gene therapy is the rapid clearance of the virus from the circulation. Viral particles have been coated with polyethylene glycol (PEG) to evade immune recognition, a strategy that works well in mouse models. However, less is known about the effects of adenoviral PEGylation in human blood. We have studied cell interactions and immune responses to PEGylated and uncoated Ad5 vectors in human whole blood using a blood loop model with constant blood flow. Limited effects of PEGylation were observed in human blood, which were associated with the neutralizing ability of the donor blood. An important finding that donors with high neutralizing ability in whole blood do not necessarily have neutralizing antibodies against the virus strongly implies that neutralization should be measured in whole blood.
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