895 resultados para Prostate Cancer Detection
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No abstract available.
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Monocarboxylate Transporter 2 (MCT2) is a major pyruvate transporter encoded by the SLC16A7 gene. Recent studies pointed to a consistent overexpression of MCT2 in prostate cancer (PCa) suggesting MCT2 as a putative biomarker and molecular target. Despite the importance of this observation the mechanisms involved in MCT2 regulation are unknown. Through an integrative analysis we have discovered that selective demethylation of an internal SLC16A7/MCT2 promoter is a recurrent event in independent PCa cohorts. This demethylation is associated with expression of isoforms differing only in 5'-UTR translational control motifs, providing one contributing mechanism for MCT2 protein overexpression in PCa. Genes co-expressed with SLC16A7/MCT2 also clustered in oncogenic-related pathways and effectors of these signalling pathways were found to bind at the SLC16A7/MCT2 gene locus. Finally, MCT2 knock-down attenuated the growth of PCa cells. The present study unveils an unexpected epigenetic regulation of SLC16A7/MCT2 isoforms and identifies a link between SLC16A7/MCT2, Androgen Receptor (AR), ETS-related gene (ERG) and other oncogenic pathways in PCa. These results underscore the importance of combining data from epigenetic, transcriptomic and protein level changes to allow more comprehensive insights into the mechanisms underlying protein expression, that in our case provide additional weight to MCT2 as a candidate biomarker and molecular target in PCa.
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This work describes preliminary results of a two-modality imaging system aimed at the early detection of breast cancer. The first technique is based on compounding conventional echographic images taken at regular angular intervals around the imaged breast. The other modality obtains tomographic images of propagation velocity using the same circular geometry. For this study, a low-cost prototype has been built. It is based on a pair of opposed 128-element, 3.2 MHz array transducers that are mechanically moved around tissue mimicking phantoms. Compounded images around 360 degrees provide improved resolution, clutter reduction, artifact suppression and reinforce the visualization of internal structures. However, refraction at the skin interface must be corrected for an accurate image compounding process. This is achieved by estimation of the interface geometry followed by computing the internal ray paths. On the other hand, sound velocity tomographic images from time of flight projections have been also obtained. Two reconstruction methods, Filtered Back Projection (FBP) and 2D Ordered Subset Expectation Maximization (2D OSEM), were used as a first attempt towards tomographic reconstruction. These methods yield useable images in short computational times that can be considered as initial estimates in subsequent more complex methods of ultrasound image reconstruction. These images may be effective to differentiate malignant and benign masses and are very promising for breast cancer screening. (C) 2015 The Authors. Published by Elsevier B.V.
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Prostate cancer, the leading cause of cancer in men, has positive survival rates and constitutes a challenge to men with its side effects. Studies have addressed the bivaritate relationships between prostate cancer treatment side effects masculinity, partner relationship, and quality of life (QOL). However, few studies have highlighted the relationships among prostate cancer treatment side effects (i.e., sexual dysfunction, urinary incontinence), masculinity, and relationship with the partner together on QOL in men. Most studies were conducted with predominately Caucasian sample of men. Miami is a unique multiethnic setting that hosts Cuban, Columbian, Venezuelan, Haitian, other Latin American and Caribbean communities that were not represented in previous literature. The purpose of this study was to examine relative contributions of age, ethnicity, sexual dysfunction, urinary incontinence, masculinity, and perception of the relationship with the partner on the quality of life in men diagnosed with prostate cancer. Data were collected using self administered questionnaires measuring demographic variables, sexual and urinary functioning (UCLA PCI), masculinity (CMNI), partner relationship (DAS), and QOL (SF-36). A total of 117 partnered heterosexual men diagnosed with prostate cancer were recruited from four urology clinics in Miami, Florida. Men were 67.47 (SD = 8.42) years old and identified themselves to be of Hispanic origin (54.3 %, n = 63). Findings demonstrated that there was a significant moderate negative relationship between urinary and sexual functioning of men. There was a significant strong negative association between men’s perceived relationship with partner and masculinity. There was a weak negative relationship between the partner relationship and QOL. Hierarchal multiple regression showed that the partner relationship (β = -.25, t (91) = -2.28, p = .03) significantly contributed overall to QOL. These findings highlight the importance of the relationship satisfaction in the QOL of men with prostate cancer. Nursing interventions to enhance QOL for these men should consider strengthening the relationship and involving the female partner as an active participant.
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AMP-activated protein kinase (AMPK) is a key regulator of cell energy homeostasis. More recently, it has become apparent that AMPK regulates cell proliferation, migration and inflammation. Previous evidence has suggested that AMPK may influence proliferation and invasion by regulating the pro-proliferative mitogen-activated protein kinases (MAPKs). However, the mechanisms underlying this crosstalk between AMPK and MAPK signalling are not fully understood. As AMPK activation has been reported to have anti-proliferative effects, there has been increasing interest in AMPK activation as a therapeutic target for tumourigenesis. The aim of this study was to investigate whether AMPK activation influenced prostate cancer (PC) cell line proliferation, migration and signalling. Therefore, different PC cell lines were incubated with two structurally-unrelated molecules that activate AMPK by different mechanisms, AICAR and A769662. Both chemicals activated AMPK in a concentration- and time-dependent manner in PC3, DU145 and LNCaP cell lines. AMPK activity as assessed by AMPK activating phosphorylation as well as phosphorylation of the AMPK substrate ACC increased along with tumour severity in PC biopsies. Furthermore, both activators of AMPK decreased cell proliferation and migration in the androgen-independent PC cell lines PC3 and DU145. Inhibition of proliferation by A769662 was attenuated in AMPK α1-/- AMPK α2-/- knockout (KO) mouse embryonic fibroblasts (MEFs) compared to wild type (WT) MEFs, and the inhibitory effect on migration of AICAR lost significance in PC3 cells infected with adenoviruses expressing a dominant negative AMPK α mutant, indicating these effects are partially mediated by AMPK. Furthermore, long-term activation of AMPK was associated with inhibition of both the phosphatidylinositol 3’-kinase/protein kinase B (PI3K/Akt) signalling pathway in addition to the extracellular signal-regulated kinase 1/2 (ERK1/2) signalling pathway. Indeed, the actions of AMPK activators on PC cell line viability were mimicked by selective inhibitors of Akt and ERK1/2 pathways. In contrast to the effects of prolonged incubation with AMPK activators, short-term incubation with AMPK activators had no effect on epidermal growth factor (EGF)-stimulated ERK1/2 phosphorylation in PC cell lines. In addition, AMPK activation did not influence phosphorylation of the other MAPK family members p38 and JNK. Interestingly, both AICAR and A769662 decreased EGF-stimulated ERK5 phosphorylation in PC3, DU145 and LNCaP cells as assessed with an anti-phospho-ERK5 antibody. Further characterisation of this effect indicated that prior stimulation with the AMPK activators had no effect on ERK5 phosphorylation stimulated by transient transfection with a constitutively active ERK5 kinase (MEK5DD), which represents the only known canonical kinase for ERK5. Intriguingly, the pattern of EGF-stimulated ERK5 phosphorylation was distinct from that mediated by MEK5DD activation of ERK5. This finding indicates that AMPK activation inhibits EGF-stimulated ERK5 phosphorylation at a point at or above the level of MEK5, although why EGF and constitutively active MEK5 stimulate markedly different immunoreactive species recognised by the anti-phospho-ERK5 antibody requires further study. A769662 had a tendency to reduce EGF-stimulated ERK5 phosphorylation in WT MEFs, yet was without effect in MEFs lacking AMPK. These data indicate that AMPK may underlie the effect of A769662 to reduce EGF-stimulated ERK5 phosphorylation. Prolonged stimulation of PC cell lines with AICAR or A769662 inhibited EGF-stimulated Akt Ser473 phosphorylation, whereas only incubation with A769662 rapidly inhibited Akt phosphorylation. This difference in the actions of the different AMPK activators may suggest an AMPK-independent effect of A769662. Furthermore, AICAR increased phosphorylation of Akt in WT MEFs, an effect that was absent in MEFs lacking AMPK, indicating that this effect of AICAR may be AMPK-dependent. Taken together, the data presented in this study suggest that AMPK activators markedly inhibit proliferation and migration of PC cell lines, reduce EGF-stimulated ERK1/2 and Akt phosphorylation after prolonged incubation and rapidly inhibit ERK5 phosphorylation. Both AMPK activators exhibit a number of effects that are likely to be independent of AMPK in PC cell lines, although inhibition of ERK1/2, ERK5 and Akt may underlie the effects of AMPK activators on proliferation, viability and migration. Further studies are required to understand the crosstalk between those signalling pathways and their underlying significance in PC progression.
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Objective The objective of this study was to develop a clinical nomogram to predict gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography (68Ga-PSMA-11-PET/CT) positivity in different clinical settings of PSA failure. Materials and methods Seven hundred three (n = 703) prostate cancer (PCa) patients with confirmed PSA failure after radical therapy were enrolled. Patients were stratified according to different clinical settings (first-time biochemical recurrence [BCR]: group 1; BCR after salvage therapy: group 2; biochemical persistence after radical prostatectomy [BCP]: group 3; advanced stage PCa before second-line systemic therapies: group 4). First, we assessed 68Ga-PSMA-11-PET/CT positivity rate. Second, multivariable logistic regression analyses were used to determine predictors of positive scan. Third, regression-based coefficients were used to develop a nomogram predicting positive 68Ga-PSMA-11-PET/CT result and 200 bootstrap resamples were used for internal validation. Fourth, receiver operating characteristic (ROC) analysis was used to identify the most informative nomogram’s derived cut-off. Decision curve analysis (DCA) was implemented to quantify nomogram’s clinical benefit. Results 68Ga-PSMA-11-PET/CT overall positivity rate was 51.2%, while it was 40.3% in group 1, 54% in group 2, 60.5% in group 3, and 86.9% in group 4 (p < 0.001). At multivariable analyses, ISUP grade, PSA, PSA doubling time, and clinical setting were independent predictors of a positive scan (all p ≤ 0.04). A nomogram based on covariates included in the multivariate model demonstrated a bootstrap-corrected accuracy of 82%. The nomogram-derived best cut-off value was 40%. In DCA, the nomogram revealed clinical net benefit of > 10%. Conclusions This novel nomogram proved its good accuracy in predicting a positive scan, with values ≥ 40% providing the most informative cut-off in counselling patients to 68Ga-PSMA-11-PET/CT. This tool might be important as a guide to clinicians in the best use of PSMA-based PET imaging.
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The treatment of metastatic castration-resistant prostate cancer (mCRPC) is currently characterized by several drugs with different mechanisms of action, such as new generation hormonal agents (abiraterone, enzalutamide), chemotherapy (docetaxel, cabazitaxel), PARP inhibitors (olaparib) and radiometabolic therapies (radium-223, LuPSMA). There is an urgent need to identify biomarkers to guide personalized therapy in mCRPC. In recent years, the status of androgen receptor (AR) gene detected in liquid biopsy has been associated with outcomes in patients treated with abiraterone or enzalutamide. More recently, plasma tumor DNA (ptDNA) and its changes during treatment have been identified as early indicators of response to anticancer treatments. Recent works also suggested a potential role of tumor-related metabolic parameters of 18Fluoro-Choline Positron Emission Tomography (F18CH-PET)-computed tomography (CT) as a prognostic tool in mCRCP. Other clinical features, such as the presence of visceral metastases, have been correlated with outcome in mCRPC patients. Recent studies conducted by our research group have designed and validated a prognostic model based on the combination of molecular characteristics (ptDNA levels), metabolic features found in basal FCH PET scans (metabolic tumor volume values, MTV), clinical parameters (absence or presence of visceral metastases), and laboratory tests (serum lactate dehydrogenase levels, LDH). Within this PhD project, 30 patients affected by mCRPC, pre-treated with abiraterone or enzalutamide, candidate for taxane-based treatments (docetaxel or cabazitaxel), have been prospectively evaluated. The prognostic model previously described was applied to this population, to interrogate its prognostic power in a more advanced cohort of patients, resulting in a further external validation of the tool.
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AIMS: The present is a retrospective evaluation of acute genito-urinary (GU) and gastro-intestinal (GI) toxicity, in addition to biochemical recurrence rate in 57 prostate cancer patients treated at our Institution with ultra-hypofractionated RT (UHRT) schedule. METHODS: From January 2021 to December 2022 we have treated 57 patients with prostate cancer, using an UHRT scheme of 5-fractions every other day for a total dose delivered of 36.25 Gy, according to the PACE-B trial treatment schedule. Good urinary function, assessed by International Prostate Symptom Score (IPSS), were required. The simulation CT scans were acquired in supine position and fused with MRI for CTVs definition for every patient. Each treatment was performed by Accuray's TomoTherapy with daily IGRT. The evaluation of the set-up was very restrictive before daily treatment delivery. RESULTS: According to RTOG toxicity scale, the acute GU toxicity at 3 months from RT, GU toxicity was G0 for 30 patients (52.6%), G1 for 26 (45.6%) and G2 for one only (1.75%); rectal toxicity was G0 for 56 patients (98.25%) and G1 for one only (1.75%). The median follow-up (FU) was 9 months (2-24 months). In the following FU months, we observed progressively lower urinary and rectal toxicity, except for one patient who showed G2 GU toxicity at 12 months. All but one patient had a progressive PSA value decrease. CONCLUSIONS: In our experience, UHRT appears to be safe and well tolerated even without the use of rectal spacer devices. A longer FU is necessary to evaluate late toxicity and disease control rate.
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Background: The early identification of responsive and resistant patients to androgen-receptor targeting agents (ARTA) in metastatic castration resistant-prostate cancer (CRPC) is not completely possible with PSA assessment and conventional imaging. Considering its ability to determine metabolic activity of lesions, PET assessment might be a promising tool. Materials and methods: We performed a monocentric prospective study in patients with metastatic CRPC under treatment with ARTA to evaluate the role of different PET radiotracers: 49 patients were randomized to receive 11C-Choline, 18F-FACBC or 68Ga-PSMA PET, one scan before therapy onset and one two months later. The primary aim was to investigate the performance of three different novel PET radiotracers for the early evaluation of response to ARTA in metastatic CRPC patients; with regards to this aim, the outcome evaluated was biochemical response (PSA reduction ≥50%). The secondary aim was to investigate the prognostic role of several semiquantitative PET parameters and their variations with the different radiotracers in terms of biochemical PFS (bPFS) and overall survival (OS). The study was promoted by the Italian Department of Health (code RF-2016-02364809). Results: With regards to the primary endpoint, at univariate analysis a statistically significant correlation was found between MTV_VARIATION% (p=0.018) and TLA_VARIATION% (p=0.025) with 68Ga-PSMA PET and biochemical response. As for the secondary endpoints, significant correlations with bPFS were found for 68Ga-PSMA PET MTV_TOT_PET1 (p=0.001), TLA_TOT_PET1 (p=0.025), MTV_VARIATION% (p=0.031). For OS, statistically significant correlations were found for: MAJ_SUV_MAX_PET1 with 11C-Choline PET (p=0.007); MTV_TOT_PET1 (p=0.004), MAJ_SUV_MAX_PET1 (p=0.029), SUVMAX_VARIATION% (p=0.04), MTV_VARIATION% (p=0.015), TLA_VARIATION% (p=0.03) with 68Ga-PSMA PET,; MTV_TOT_PET1 (p=0.011), TLA_TOT_PET1 (p=0.009), MAJ_SUV_MAX_PET1 (p=0.027), MTV_VARIATION% (p=0.048) with 18F-FACBC. Conclusions: Our prospective study highlighted that several 68Ga-PSMA and 18F-FACBC semiquantitative PET parameters and their variations present a prognostic value in terms of OS and bPFS and a correlation with biochemical response, that could help to assess response to ARTA.
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In 2011, therapeutic acquisitions in urology allow optimizing management of acute uncomplicated cystitis and acute pyelonephritis by female patients and in men clinical implications of benign prostatic hyperplasia opposed to prostate cancer detection as well as hormonal treatment of advanced prostate cancer.
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Pós-graduação em Bases Gerais da Cirurgia - FMB
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Ultrasound imaging is widely used in medical diagnostics as it is the fastest, least invasive, and least expensive imaging modality. However, ultrasound images are intrinsically difficult to be interpreted. In this scenario, Computer Aided Detection (CAD) systems can be used to support physicians during diagnosis providing them a second opinion. This thesis discusses efficient ultrasound processing techniques for computer aided medical diagnostics, focusing on two major topics: (i) Ultrasound Tissue Characterization (UTC), aimed at characterizing and differentiating between healthy and diseased tissue; (ii) Ultrasound Image Segmentation (UIS), aimed at detecting the boundaries of anatomical structures to automatically measure organ dimensions and compute clinically relevant functional indices. Research on UTC produced a CAD tool for Prostate Cancer detection to improve the biopsy protocol. In particular, this thesis contributes with: (i) the development of a robust classification system; (ii) the exploitation of parallel computing on GPU for real-time performance; (iii) the introduction of both an innovative Semi-Supervised Learning algorithm and a novel supervised/semi-supervised learning scheme for CAD system training that improve system performance reducing data collection effort and avoiding collected data wasting. The tool provides physicians a risk map highlighting suspect tissue areas, allowing them to perform a lesion-directed biopsy. Clinical validation demonstrated the system validity as a diagnostic support tool and its effectiveness at reducing the number of biopsy cores requested for an accurate diagnosis. For UIS the research developed a heart disease diagnostic tool based on Real-Time 3D Echocardiography. Thesis contributions to this application are: (i) the development of an automated GPU based level-set segmentation framework for 3D images; (ii) the application of this framework to the myocardium segmentation. Experimental results showed the high efficiency and flexibility of the proposed framework. Its effectiveness as a tool for quantitative analysis of 3D cardiac morphology and function was demonstrated through clinical validation.
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Hintergrund: Die Systembiopsie gilt als Goldstandard zum Nachweis eines Prostatakarzinoms, obwohl ein relevanter Anteil an Prostatakarzinomen nicht diagnostiziert wird. Wir wollten mit unserer Arbeit die Frage beantworten, ob mittels elastographisch gezielter Biopsien die Prostatakarzinom-Detektion im Vergleich zur Goldstandard-Systembiopsie verbessert werden kann. Material und Methode: 152 Patienten wurden in einer prospektiven Studie einer 12-fachen Prostata-Systembiopsie unterzogen. In Linksseitenlagerung wurde dabei aus jedem der vordefinierten 6 Prostatasegmente je 1 laterale und 1 mediale Stanze entnommen. Elastographisch suspekte Areale wurden zusätzlich gezielt biopsiert. Als statistisch signifikant wurde p<0,05 angenommen. Ergebnisse: Bei 62 der 152 Patienten (40,8%) wurde ein Prostatakarzinom diagnostiziert. Die Detektionsrate der Systembiopsie betrug 39,5% (60/152), die Detektionsrate der Elastographie 29,6% (45/152). Somit war die Systembiopsie der elastographisch gezielten Biopsie signifikant überlegen (p=0,039).Jedoch war die Wahrscheinlichkeit mit einer Prostatastanze ein Karzinomherd zu entdecken, für die elastographischen Biopsien 3,7-fach höher als für die Systembiopsien. Die Sensitivität der Elastographie betrug 72,6% und die Spezifität 66,6%. Der positive Vorhersagewert für die Elastographie war 60%, der negative Vorhersagewert 78%. Die Kombination von Systembiopsie und elastographisch gezielten Biopsien bot die höchste Detektionsrate. In der rechten Prostatahälfte (48%) verzeichneten wir doppelt so viele elastographisch falsch-positive Befunde wie in der linken Prostatahälfte (25%). Desweiteren fanden sich am häufigsten falsch-positive Befunde im Prostata-Apex (46%) und am seltensten in der Prostata-Basis (29%). Schlussfolgerung: In unserer Studie war die elastographisch gezielte Biopsie der Systembiopsie signifikant unterlegen (p=0,039). Die Kombination von Systembiopsie mit elastographisch gezielten Biopsien bot die höchste Detektionsrate und kann daher empfohlen werden. Die Auffälligkeiten in der Segment-bezogenen Auswertung und ein möglicher Einfluss der Patienten-Lagerung müssen durch weitere Studien überprüft werden.rn