Tse, Ho Man. / Thesis (M.Phil)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 166-173). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / 撮要 --- p.v / Table of Content --- p.vi / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Basis of Prostate Cancer --- p.1 / Chapter 1.1.1 --- Epidemiology and Risk Factors of Prostate Cancer --- p.1 / Chapter 1.1.2 --- Pathology of Prostate Cancer --- p.2 / Chapter 1.1.3 --- Treatment Approaches for Prostate Cancer --- p.4 / Chapter 1.2 --- Sex Hormones and Prostate Cancer --- p.7 / Chapter 1.2.1 --- Prostate Development --- p.7 / Chapter 1.2.2 --- Involvement of Sex Hormones in Prostate Cancer --- p.8 / Chapter 1.2.3 --- Molecular Mechanisms of Sex Hormones --- p.13 / Chapter 1.2.4 --- Hormone Receptor Antagonists --- p.15 / Chapter 1.3 --- Involvement of microRNAs in Cancer --- p.19 / Chapter 1.3.1 --- Basis of microRNAs --- p.19 / Chapter 1.3.2 --- Aberrant microRNA Expressions in Cancers --- p.23 / Chapter 1.3.3 --- Current Understandings on Regulations of micro RN A Expressions --- p.26 / Chapter 1.3.4 --- Regulation of miRNA Expressions by Hormones --- p.29 / Chapter 1.4 --- "Effects of the Anti-estrogen ICI 182,780 on Prostate Cancer Cells" --- p.30 / Chapter 1.4.1 --- "ICI 182,780 Inhibits Cell Growth ofDU145" --- p.30 / Chapter 1.5 --- Objectives of Project --- p.32 / Chapter Chapter 2: --- Materials --- p.34 / Chapter 2.1 --- Bacteria Strain --- p.34 / Chapter 2.2 --- Tissue Culture Media --- p.34 / Chapter 2.3 --- Plasmids --- p.34 / Chapter 2.4 --- Kits and Accessories --- p.35 / Chapter 2.5 --- Reagents and Solutions --- p.36 / Chapter 2.6 --- DNA Oligos --- p.38 / Chapter 2.7 --- Equipments --- p.40 / Chapter Chapter 3: --- Methods --- p.41 / Chapter 3.1 --- Cell Culture Conditions --- p.41 / Chapter 3.2 --- miRNA Expression Profiling of DU145 --- p.41 / Chapter 3.2.1 --- RNA Isolation --- p.41 / Chapter 3.2.2 --- miRNA Microarray Profiling ofDU145 : --- p.42 / Chapter 3.2.2.1 --- Fluorescent Labeling of RNA and Microarray Hybridization --- p.42 / Chapter 3.2.2.2 --- Scanning and Analysis of Signals --- p.46 / Chapter 3.2.3 --- Confirming miR-765 Up-regulation by ICI with qRT-PCR --- p.46 / Chapter 3.2.3.1 --- Assessing ERp Dependency in miR-765 Induction --- p.48 / Chapter 3.2.4 --- Effects of ICI on ARHGEF11 Expression --- p.49 / Chapter 3.2.4.1 --- Reverse Transcription of mRNA --- p.50 / Chapter 3.2.4.2 --- Quantitative Real-Time PCR for Gene mRNA expression --- p.50 / Chapter 3.3 --- Characterizing the Promoter Region of miR-765 --- p.52 / Chapter 3.3.1 --- Cloning of miR-765 Promoter into pGL3-Basic Vector --- p.52 / Chapter 3.3.1.1 --- PCR Amplification of miR-765 Putative Promoter Region --- p.52 / Chapter 3.3.1.2 --- Ligation of the Amplified Regions in pGL3-Basic Vector --- p.55 / Chapter 3.3.1.3 --- Transformation and Screening of pGL3-765 Plasmid --- p.57 / Chapter 3.3.1.4 --- Preparation of pGL3-765 Plasmid DNA --- p.59 / Chapter 3.3.2 --- Preparation of Truncated miR- 765 Promoter Clones --- p.60 / Chapter 3.3.2.1 --- pGL3-765-Trunc#l --- p.61 / Chapter 3.3.2.2 --- pGL3-765-Trunc#2 --- p.62 / Chapter 3.3.2.3 --- pGL3-765-Trunc#3 --- p.62 / Chapter 3.3.3 --- Assessing the miR- 765 Promoter Activities --- p.63 / Chapter 3.3.3.1 --- Optimizing Transfection Conditions --- p.64 / Chapter 3.3.3.2 --- Co-transfection of pGL3-765 and pRL-CMV into DU145 Cells.. --- p.64 / Chapter 3.3.3.3 --- Measuring Luciferase Activities --- p.65 / Chapter 3.3.4 --- Computational Prediction of Transcription Factor Binding Sites on miR-765 Promoter --- p.66 / Chapter 3.4 --- Characterizing the Promoter Region of ARHGEF11.. --- p.67 / Chapter 3.4.1 --- Cloning of ARHGEF11 Promoter into pGL3-Basic Vector (pGL3-ARH) --- p.67 / Chapter 3.4.1.1 --- PCR Amplification of ARHGEF11 Putative Promoter Region --- p.67 / Chapter 3.4.1.2 --- Ligation of the Amplified Regions in pGL3-Basic Vector --- p.68 / Chapter 3.4.1.3 --- Preparation of Plasmid DNA --- p.69 / Chapter 3.4.2 --- Preparation of Truncated ARHGEF11 Promoter Clones --- p.69 / Chapter 3.4.2.1 --- pGL3-ARH-Trunc#l --- p.69 / Chapter 3.4.2.2 --- pGL3-ARH-Trunc#2 --- p.70 / Chapter 3.4.2.3 --- pGL3-ARH-Trunc#3 --- p.71 / Chapter 3.4.3 --- Assessing ARHGEF11 Promoter Activities --- p.72 / Chapter 3.5 --- Identifying Transcription Factor Binding Sites on ARHGEF11 Promoter with EMS A --- p.73 / Chapter 3.5.1 --- Computational Prediction --- p.73 / Chapter 3.5.2 --- Preparation of Biotinylated Probe for use in EMSA --- p.73 / Chapter 3.5.3 --- Preparation of Specific Competitors --- p.74 / Chapter 3.5.4 --- Preparation of DU145 Nuclear and Cytoplasmic Extracts --- p.75 / Chapter 3.5.4.1 --- Preparation of Extracts --- p.75 / Chapter 3.5.4.2 --- Measuring Protein Concentrations --- p.76 / Chapter 3.5.5 --- EMSA Detection of Interaction between Protein and Probe --- p.76 / Chapter 3.6 --- Assessing Biological Significances of miR-765 --- p.78 / Chapter 3.6.1 --- Effects of ICI on DU145 Cells Growth --- p.79 / Chapter 3.6.2 --- Effects of ICI on DU145 Migration Ability --- p.79 / Chapter 3.6.2.1 --- Monolayer Wound Healing Assay --- p.79 / Chapter 3.6.2.2 --- Transwell Migration Assay --- p.80 / Chapter 3.6.3 --- Validating Functionality of Ectopic miR- 765 --- p.81 / Chapter 3.6.3.1 --- miR-765 Recognition Sequence --- p.81 / Chapter 3.6.3.2 --- Preparation of pMIR-765 vector --- p.82 / Chapter 3.6.3.3 --- Ectopic Introduction of miR-765 into DU145 Cells --- p.84 / Chapter 3.6.3.4 --- "Verifying Functionality, of Ectopic miR-765" --- p.84 / Chapter 3.6.4 --- Effects of miR-765 on DU145 Growth --- p.86 / Chapter 3.6.5 --- Effects of miR-765 on DU145 Migration Ability --- p.86 / Chapter 3.7 --- Statistical Analysis --- p.87 / Chapter Chapter 4: --- Results --- p.88 / Chapter 4.1 --- "Identifying ICI 182,780-Regulated miRNA in DU145 Cells" --- p.88 / Chapter 4.1.1 --- miRNA Expression Profiling of DU145 with Microarray --- p.88 / Chapter 4.1.2 --- "Confirming Induction of miR-765 by ICI 182,780 with qRT-PCR" --- p.91 / Chapter 4.1.3 --- "ARHGEF11, Host Gene of miR-765" --- p.95 / Chapter 4.1.4 --- "Induction of ARHGEF 11 by ICI 182,780" --- p.96 / Chapter 4.2 --- Characterization miR-765 Promoter Region --- p.98 / Chapter 4.2.1 --- Cloning of miR- 765 Promoter Region into pGLS-Basic Vector --- p.98 / Chapter 4.2.2 --- Promoter Activity of miR-765 Promoter --- p.100 / Chapter 4.2.3 --- Deletion Mapping of miR- 765 Promoter Region --- p.102 / Chapter 4.2.4 --- Promoter Activities and Inducibitiy of Truncated miR-765 Promoters --- p.103 / Chapter 4.2.5 --- Computational Prediction of Transcription Factor Binding Sites on miR-765 Promoter --- p.105 / Chapter 4.3 --- Characterization of ARHGEF 11 Promoter Region --- p.107 / Chapter 4.3.1 --- Cloning of ARHGEF 11 Promoter --- p.107 / Chapter 4.3.2 --- Promoter Activitiy of ARHGEFll Promoter --- p.109 / Chapter 4.3.3 --- Deletion Mapping of ARHGEFll Promoter --- p.111 / Chapter 4.3.4 --- Promoter Activities and Inducibitiy of Truncated ARHGEF 11 Promoters --- p.113 / Chapter 4.4 --- Identifying Transcription Factor Binding Sites on ARHGEF 11 Promoter --- p.115 / Chapter 4.4.1 --- Computational Prediction of Transcription Factor Binding Sites onARHGEFll Promoter --- p.115 / Chapter 4.4.2 --- Preparation of Probe and Specific Competitors for EMSA --- p.117 / Chapter 4.4.3 --- Interaction between DU145 Nuclear Extract and ARHGEF 11 Promoter Region --- p.119 / Chapter 4.5 --- Biological Significances of miR-765 --- p.122 / Chapter 4.2.1 --- "Effects of ICI 182,780 on DU145 Cell growth" --- p.122 / Chapter 4.2.2 --- "Effects of ICI 182,780 on DU145 Cell Migration" --- p.124 / Chapter 4.2.3 --- Verifying Functionality of Ectopic miR-765 --- p.131 / Chapter 4.2.4 --- Effects of miR-765 on DU145 Cell Growth --- p.133 / Chapter 4.2.5 --- Effects of miR-765 on DU145 Cell Migration --- p.135 / Chapter Chapter 5: --- Discussion --- p.138 / Chapter 5.1 --- "Identifying miR-765 as an Up-regulated miRNA by ICI 182,780" --- p.139 / Chapter 5.1.1 --- "Information about ICI 182,780" --- p.139 / Chapter 5.1.2 --- miRNA Profiling of DU145 --- p.139 / Chapter 5.1.3 --- "Confirming Induction of miR-765 by ICI 182,780 and ERβ dependency with qRT-PCR" --- p.140 / Chapter 5.1.4 --- "Up-regulation of miR-765 Host Gene, ARHGEF11, by ICI" --- p.141 / Chapter 5.2 --- Regulatory Elements of miR-765 Expression --- p.143 / Chapter 5.2.1 --- Own Upstream promoter of miR- 765 --- p.144 / Chapter 5.2.2 --- Promoter of Host Gene ARHGEF11 --- p.146 / Chapter 5.2.3 --- Interaction between ARHGEF11 Promoter Critical Region and Transcription Factors --- p.147 / Chapter 5.2.4 --- Involvement of independent Promoter and Host Gene Promoter in miR-765 Regulation --- p.757 / Chapter 5.3 --- Biological Significances of miR-765 on DU145 --- p.153 / Chapter 5.4 --- Significance of Findings and Future Studies --- p.158 / Chapter 5.4.1 --- Clinical Significance --- p.158 / Chapter 5.4.2 --- Future Studies --- p.161 / Chapter Chapter 6: --- Conclusion --- p.163 / Chapter Chapter 7: --- References --- p.166

A prostatectomia radical (PR) é um dos procedimentos mais utilizados para o tratamento do câncer de próstata (CaP) localizado, porém apesar da maior compreensão da anatomia local e do desenvolvimento tecnológico, esta cirurgia permanece associada à elevada morbidade na esfera sexual. A redução do comprimento peniano após a PR é uma queixa freqüente na prática urológica, porém não há dados na literatura a respeito da variação deste comprimento em um longo período de acompanhamento. A determinação da história natural do comprimento peniano após PR, assim como possíveis fatores de risco ou de proteção é de fundamental importância para o aconselhamento e tratamento dos pacientes submetidos a esta cirurgia. O objetivo deste estudo é determinar a história natural do comprimento peniano após a PR em um acompanhamento de cinco anos, assim como avaliar o papel da função erétil na variação do comprimento peniano destes pacientes. Foram avaliados prospectivamente os comprimentos penianos de 105 pacientes com câncer de próstata localizado submetidos PR aberta. Participação em programas de reabilitação peniana e deformidades anatômicas do pênis foram considerados critérios de exclusão. A medição do comprimento real peniano sob máxima tração (CRTmax) foi realizada antes da PR e aos 3, 6, 12, 24, 36, 48 e 60 meses no pós-operatório. O domínio da função erétil do índice internacional de função erétil (IIEF-EF) foi utilizado para avaliar a função erétil. Houve redução média de 1 cm no CRTmax em 3 meses após a PR e essa diferença permaneceu até 24 meses (p<0,001). Após este período, a diferença reduziu gradativamente, deixando de ser estatisticamente significativa em 48 meses (-0,3 cm, p=0,080) e 60 meses (+0,4 cm, p=0,065). A função erétil foi um preditor para o retorno precoce do comprimento do pênis. Um encurtamento peniano médio de 1 cm é esperado nos primeiros 24 meses após PR. No entanto, há uma tendência para a recuperação deste comprimento após 24 meses de pós-operatório, com retorno ao comprimento original em 48 meses. A função erétil preservada após a PR é um preditor para a recuperação precoce do comprimento do pênis / Radical prostatectomy (RP) is one of the most common treatment for localized prostate cancer (PCa), but despite the advances in the local anatomy knowledge and the technological development, this surgery remains related to high morbidity in the sexual sphere. The reduction in penile length after RP is a common complaint in urologic practice, but there is no data regarding this issue in a long follow-up period. The determination of the natural history of penile length after RP and possible risk factor is necessary for the counseling and treatment of patients undergoing this surgery. The objective of this study is to determine the natural history of penile length after RP in a five years follow-up and to investigate the role of erectile function in the penile length variation. We prospectively evaluated the penile length of 105 patients with localized prostate cancer submitted to open RP. Participation in penile rehabilitation programs and anatomical deformities of the penis were considered exclusion criteria. Measurements of the real length under maximum penile traction (RSLmax) were performed before and after RP at 3, 6, 12, 24, 36, 48 and 60 months postoperatively. The erectile function domain of the International Index of Erectile Function (IIEF-EF) was used to assess erectile function. There was a mean reduction of 1 cm in RSLmax in 3 months after the PR and this difference remained up to 24 months (p <0.001). After this period, the difference decreased gradually and was not statistically significant at 48 months (-0.3 cm, p = 0.080) and 60 months (+0.4 cm, p = 0.065). Erectile function was a predictor for the early recovery of penile length. In conclusion, a mean penile shortening about 1 cm is expected in the first 24 months after RP. However, there is a tendency for the recovery of this length after 24 months postoperatively, with a return to the original length at 48 months. The normal erectile function after RP is a predictor for early recovery of penile length

Made available in DSpace on 2014-06-11T19:30:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-25Bitstream added on 2014-06-13T18:41:13Z : No. of bitstreams: 1 moroz_a_dr_botib.pdf: 3424039 bytes, checksum: a7c3216b5e555a810395696e16f33e9b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O câncer de próstata (CaP) é importante causa de morte no mundo. Além do óbvio impacto na vida pessoal do paciente e na sua família, no Brasil esta doença gera custos altíssimos para o Sistema Único de Saúde (SUS), desde o diagnóstico até o óbito. As terapias disponíveis, além de causarem complicações e efeitos colaterais indesejáveis, não proporcionam sobrevida alta ao paciente. Além disso, os casos de cura são restritos aos diagnosticados precocemente, e com intervenção rápida, antes que o tumor se torne resistente à castração química. Neste sentido, estratégias preventivas são desejáveis para a diminuição da incidência e óbitos e, dentre elas, o uso da finasterida, um fármaco inibitório da enzima 5-α-redutase, foi proposto como potencial agente quimiopreventivo após estudo conduzido pelo Prostate Cancer Prevention Trial, que demonstrou significante diminuição na incidência de CaP no grupo de pacientes tratados, em comparação ao grupo controle. No entanto, mesmo com resultados promissores, foi detectado aumento, também significante, do número de casos de cânceres mais agressivos (alto grau) no grupo de pacientes que recebeu finasterida, em comparação aos pacientes do grupo controle. Após intenso debate entre urologistas, biologistas e cancerologistas, ainda não há consenso sobre a natureza artefatual ou de real indução de cânceres mais agressivos pela finasterida. O órgão regulatório americano Food and Drugs Administration (FDA) declarou que o aumento dos casos agressivos pela finasterida não deve ser negligenciado, e recentemente proibiu o uso deste fármaco como quimiopreventivo para o CaP. Uma vez que casos agressivos de câncer estão comumente relacionados à superexpressão de enzimas... / Prostate cancer (PCa) is an important death cause in Brazil and other countries. Besides the obvious impact at patient’s life, and their relatives, this disease consumes exorbitant resources from the Sistema Único de Saúde (SUS), from diagnosis to death. The available therapies not only cause undesirable complications and side effects, but also are inefficient at providing good survival expectancies for those affected. Moreover, the cure is only possible when the tumors are readily found and when the intervention is fast enough to prevent that the tumor become castration-resistant. In this sense, preventive strategies are desirable in order to lower incidence and death, and amongst them, finasteride (Fin) treatment, an inhibitor of the 5-alpha reductase enzyme, was proposed as a potential chemopreventive agent after the study conducted by the Prostate Cancer Prevention Trial reported a significant lower incidence of PCa cases on Fin-treated patients, when compared to control patients. However, even though these results were promising, this study also reported a significant increase on more aggressive, high-grade PCa, amongst Fin-treated patients, compared to those not exposed to Fin. After an intense debate about factual or artifactual Fin-induced high-grade PCa cases, between urologists, biologists and oncologists, there are still no decisive conclusions on this matter. The regulatory USA organ, Food and Drugs Administration (FDA), has recently declared that the higher incidence of a more serious form of PCa at the Fin-treated patients must not be neglected, and prohibited its use as a chemopreventive agent. Given that the aggressive cancer cases are commonly associated with the super-expression of matrix metalloproteinases (MMPs) enzymes, with consequently higher invasion and migration potential of tumor... (Complete abstract click electronic access below)

Cette thèse porte sur la prise en compte des variations anatomiques, notamment les déformations d’organes à risque (rectum, vessie), pouvant survenir lors du traitement de radiothérapie conformationnelle par modulation d’intensité du cancer de la prostate. Ces variations peuvent entrainer d’importants écarts dosimétriques par rapport au plan de traitement initialement optimisé, et augmenter le risque de complications. Grâce à l’évolution des dispositifs d’imagerie et des méthodes de traitement d’images, des approches permettant de cumuler la dose au cours du traitement ont été récemment proposées mais restent mal évaluées et leur intégration dans un schéma de radiothérapie adaptative suscite de nombreuses questions. Ainsi, la première partie de ce travail a consisté à évaluer, à l’aide d’un fantôme numérique, une méthode de suivi de dose développée récemment au LTSI. Les résultats obtenus ont montré que les incertitudes dosimétriques liées à l’algorithme de cumul de dose sont limitées par rapport aux dérives dosimétriques observées chez les patients. La seconde partie de ce travail a consisté à proposer une stratégie de radiothérapie adaptative reposant sur le suivi de dose et à évaluer son bénéfice dosimétrique sur trois patients pour lesquels des dérives avaient été observées. Le principe de cette méthode est de détecter les dérives dosimétriques entre la dose planifiée et la dose réellement délivrée et, si besoin, de les compenser grâce à une ou plusieurs replanifications. Les résultats obtenus ont montré que cette approche permet une réduction de la dérive aux organes à risque, tout en augmentant la dose au volume cible en comparaison à un traitement standard par IGRT, avec un nombre limité de replanifications (une ou deux) permettant d’envisager une implémentation clinique. / This thesis concerns the compensation of the anatomical variations, mainly the organs at risk (rectum, bladder) deformations, which occur during intensity modulated radiotherapy of the prostate cancer. These variations can lead to significant dose drift compared to the initially planned dose, increasing the risk of toxicity. Thanks to the evolution of imaging devices and of image processing methods, dose accumulation processes, allowing to estimate the cumulated dose during the treatment, have been recently proposed. Nevertheless those strategies suffer of a lack of evaluation and their integration into an adaptive radiotherapy raises many questions. Thus, in the first part of this work, a dose accumulation method recently developed at the LTSI was evaluated using a numerical phantom. The results obtained showed that the dosimetric uncertainties related to the cumulated dose process remain low compared to the dose drifts observed for patients. The second part of this work aimed to develop a dose guided adaptive radiotherapy process and to evaluate its dosimetrical benefit using three patients showing a dose drift. The principle of this method is to detect a potential drift between the planned and actually delivered doses and, if necessary, to compensate them thanks to one or more replanning(s). The results have shown that this approach has reduced the dose drift to the organs at risk, while increasing the dose to the prostate compared to standard IGRT treatment, with a limited number of replannings (one or two), enabling to consider a clinical implementation.

O câncer de próstata (CaP) é o tumor maligno mais frequente e uma das principais causas de morte por câncer na população masculina no mundo e no Brasil. Três fatores são de fundamental importância no prognóstico da doença: o estadiamento, o grau histológico (avaliado pelo escore de Gleason) e o antígeno prostático específico (Prostate Specific Antigen - PSA). Há fatores adicionais descritos que podem influenciar na evolução do câncer, como invasão perineural, invasão angiolinfática, acometimento da cápsula, lateralidade do tumor, estágio tumoral e invasão de linfonodos. Embora a associação entre mutações do BRCA2 e o risco de câncer de próstata esteja bem documentado, pouco se sabe sobre o papel do BRCA2 na progressão do câncer de próstata após o diagnóstico inicial. O presente trabalho se propõe a melhor elucidar o papel da proteína BRCA2 nos carcinomas prostáticos comparando os resultados da expressão proteica de BRCA2 com dados clinicopatológicos de pacientes acometidos por Câncer de Próstata, além de avaliar a expressão de BRCA2 com escore de Gleason >=7 após a prostatectomia, tanto na classificação de Gleason segundo Epstein 2005, quanto na classificação do grau de Gleason definida em 2014 com suas respectivas biópsias por agulha. Dos arquivos do Serviço de Patologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, foram selecionados 125 blocos de parafina com amostras de câncer de próstata diagnosticados entre 2005 e 2010. As lâminas coradas com hematoxilina e eosina (H&E) foram utilizadas para a construção de microarranjos teciduais (TMAs). Nesses TMAs foi realizado estudo imunohistoquímico para BRCA2. A proteína BRCA2 com ponto de corte de 15% (classificação antiga) foi superexpressa em 118 casos (94,4%), enquanto a expressão de BRCA2 com cut-off de 56% (classificação nova) foi expressa em 63 (51,2%) de 125 casos. A superexpressão de BRCA2 associada a classificação antiga de Gleason correlacionou-se com bilateralidade do tumor e com estágio tumoral, em contrapartida a expressão de BRCA2 associada a atual classificação se correlacionou apenas com lesão intraepitelial prostática (PIN). Nossos resultados indicam que a expressão de BRCA2 pode ser um biomarcador importante de progressão tumoral nos carcinomas de próstata. / Prostate cancer (PCa) is the most common malignancy and a major cause of cancer death in male population in the world and in Brazil. Three factors are of fundamental importance in the prognosis of the disease: the staging, histological grade (measured by Gleason score) and the Prostate Specific Antigen (PSA). There are additional factors described that may influence the development of cancer, such as perineural invasion, angiolymphatic invasion, capsule involvement, tumor laterality, tumor stage and lymph node invasion. Although the association between mutations in Breast Cancer Gene 2 (BRCA2) and the risk of prostate cancer is well documented, little is known about the role of BRCA2 in the progression of prostate cancer after initial diagnosis. This study aims to elucidate the role of BRCA2 protein in prostate carcinomas comparing the results of the BRCA2 protein expression with clinicopathological data of patients with prostate cancer. For that reason, we evaluated the expression of BRCA2 with Gleason score >=7 after prostatectomy, both in the second Epstein 2005 Gleason score, and in the classification of Gleason grade set in 2014 with their respective needle biopsies. 125 paraffin blocks with prostate cancer samples diagnosed between 2005 and 2010 were selected from the archives of Hospital Pathology Service of the Ribeirao Preto Medical School, University of Sao Paulo. The slides stained with hematoxylin and eosin (H&E) were used for the construction of the tissue microarrays (TMAs). These TMAs was performed immunohistochemical study for BRCA2. The BRCA2 protein with a cut-off point of 15% (old classification) was overexpressed in 118 cases (94.4%), while the expression of BRCA2 to cut off 56% (new classification) was expressed in 63 (51.2%) of 125 cases. The BRCA2 associated overexpression of the old classification of Gleason presented correlation with tumor bilateralism and tumor stage, however BRCA2 expression associated with the current classification was correlated only with Prostatic Intraepithelial Lesion (PIN). Our results indicate that BRCA2 expression can be an important marker of tumor progression in prostate carcinomas.

Dentre as diversas formas de se tratar o câncer de próstata, a braquiterapia com sementes de iodo-125 é uma opção que apresenta ótimos resultados e menor ocorrência de efeito colateral. No presente trabalho diferentes métodos de deposição de iodo radioativo em substrato de prata foram comparados com o propósito de eleger a alternativa mais adequada para a produção rotineira de sementes de iodo-125 do IPEN. A metodologia utilizada foi escolhida com base na infraestrutura disponível e na experiência dos pesquisadores presentes. Por essa razão, utilizou-se o iodo-131 para realização dos testes (mesmo comportamento do iodo-125). Quatro métodos foram selecionados: Método 1 (teste de eletrodeposição baseado no método desenvolvido por D. Kubiatowicz) com a eficiência de 65,16%; Método 2 (Reação química baseada no método desenvolvido por D. Kubiatowicz - HCl) com o resultado de 70,80% de eficiência; Método 3 (Reação química baseada no método desenvolvido pela Dra Maria Elisa Rostelato aquecimento/sulfeto) com 55,80% de eficiência; Método 4 (IQ-IPEN) apresentou o melhor resultado de eficiência, 99%. Como há mais fixação do material radioativo (que representa praticamente todo o custo da semente) por esse método, o preço final é o mais barato, sendo esse o método sugerido para ser implementado no laboratório de produção de fontes de braquiterapia do IPEN. Além disso o método é o mais rápido. / Among the different ways to treat prostate cancer, brachytherapy with iodine- 125 seeds is an option that provides good results and fewer side effects. In the present study several deposition methods of radioactive iodine in a silver substrate were compared in order to choose the most suitable alternative for the routine production to be implemented at IPENs laboratory. The methodology used was chosen based on the available infrastructure and experience of the researchers present. Therefore, the I131 was used for testing (same chemical behavior as I131). Four methods were selected: Method 1 (test based on electrodeposition method developed by D.Kubiatowicz) presented 65.16% efficiency; Method 2 (chemical reaction based on the method developed by D. Kubiatowicz - HCl) with the result of 70.80% efficiency; method 3 (chemical reaction based on the method developed by Dr. Maria Elisa Rostelato) with 55.80% efficiency; Method 4 (IQ-IPEN) resulted in 99% efficiency. Since this method has more radioactive material fixation (which represents virtually the entire cost of the seed), the final price is the cheapest. This method is the suggested one to be implemented in the IPENs laboratory for brachytherapy sources production. Besides, the method is the fasted one.

A tomografia por emissão de pósitrons associada à tomografia computadorizada (PET/CT) é um dispositivo que combina as características de medicina nuclear (PET) e de radiologia (CT) obtendo imagens metabólicas (PET) e anatômicas sobrepostas (CT). Combinando as duas tecnologias de exames, o exame PET / CT permite aos médicos diagnosticar com maior precisão e identificar o câncer, doenças cardíacas e distúrbios cerebrais. O radiofármaco 18FFAc (fluoroacetato) é promissor para a detecção de tumores primários de próstata e de mama, utilizando a técnica de PET/CT. Estudos recentes mostram a eficácia do 18F-FAc na detecção de tumores que têm baixa captação de 18F-FDG (fluordesoxiglicose). O fluoroacetato é um substrato para a acetil-CoA sintase, enzima que metaboliza ácido fluorocitrato que não é mais metabolizado, levando à inibição da aconitase e do ácido tricarboxílico. O objetivo deste trabalho foi desenvolver um radiofármaco emissor de pósitron, 18F-FAc no IPEN-CNEN/SP em um acordo com o Hospital AC-Camargo / São Paulo. O íon fluoreto (18F-) foi produzido, usando os cíclotrons Cyclone 30 e 18 da IBA localizados no IPEN-CNEN/SP, através da irradiação de água enriquecida em 18O com prótons e dose integrada de 30&mu;Ah. A marcação do 18F-FAc foi realizada em um módulo de síntese TRACERlab MXFDG (GE), utilizando kits adquiridos da ABX. O controle de qualidade radioquímico de 18F-FAc foi realizado por cromatografia em camada fina TLC-SG 25 folhas de alumínio em tiras (1,5 x 12 cm ) usando como solvente clorofórmio:metanol (1:1). Para o controle de qualidade radionuclídico, amostras de 18F-FAc e 18F-Fluoreto foram analisadas por espectroscopia de raios-gama. A avaliação dos solventes residuais foi realizada por cromatografia em fase gasosa e a análise de kryptofix foi realizada por TLC utilizando tiras de TLC-SG, metanol:clorofórmio (9:1) como solvente e padrões de kryptofix 2.2.2. Os estudos de biodistribuição foram realizados com 18FFAc injetado em camundongos swiss sadios. Um procedimento reprodutível foi desenvolvido para o preparo do 18F-FAc com um rendimento de marcação de 37% (não corrigido) e 52% (corrigido para o decaimento) e estabilidade de 19 horas. A análise de controle de qualidade mostrou que o produto tinha as exigências adequadas para utilização, com pureza radioquímica superior a 99,9%. Os estudos de biodistribuição em animais sadios mostraram a esperada captação em todos os órgãos medidos com eliminação renal e intestinal. / PET / CT (positron emission tomography / computed tomography) is a device that combines the features of diagnostic nuclear medicine (PET) and Radiology (CT) superimposing metabolic (PET) and anatomical (CT) images. By combining the two technologies examinations, the PET/CT scan allows physicians to diagnose more accurately and identify cancer, heart disease and brain disorders. The radiopharmaceutical 18F-FAc (fluoroacetate) is promising for application in detection of primary tumors of prostate and breast, using PET-CT techniques. Recent studies are showing the efficacy of the 18F-FAc in the detection of tumors that have low uptake of 18F-FDG (fluorodeoxyglucose). The fluoroacetate is a substrate for the enzyme acetyl-CoA synthase that metabolizes acid fluorcitric that, not being metabolized, causes inhibition of aconitase and inhibition of tricarboxylic acid. The aim of this work was to develop a positron emitting radiopharmaceutical, 18F-FAc at IPEN-CNEN/SP in agreement with Hospital AC-Camargo/ São Paulo. The 18F-fluoride ion was produced using the Cyclone 30 and 18 cyclotrons from IBA located at IPEN-CNEN/SP, by irradiating enriched 18O water with protons with integrated dose 30&mu;Ah. The labelling of 18F-FAc was performed in a synthesis module TRACERlab MXFDG (GE), using kits purchased from ABX. The radiochemical quality control of 18F-FAc was performed by Thin Layer Chromatography using TLC-SG 25 aluminium sheets strips (1.5 x 12 cm) and chloroform:methanol (1:1) as the solvent. For the radionuclidic quality control, samples of 18F-FAc and 18F-Fluoride were analysed by gama-ray spectroscopy. The evaluation of the residual solvents was performed by gas chromatography and the analysis of kryptofix was performed by TLC using TLC-SG strips, methanol:chloroform (9:1) as solvent and kryptofix 2.2.2 standards. Biodistribution studies were performed with 18F-FAc injected into healthy Swiss mice. A reliable procedure was developed for preparation of 18F-FAc with a labelling yield of 37% (uncorrected) and 52% (corrected for decay) and stability of 19 hours. The quality control analysis showed that the product had the proper requirements for use, with radiochemical purity exceeding 99.9%. The biodistribution studies in healthy animals showed the expected uptake results in all the measured organs with intestinal and renal elimination.

Background and aims of the study. Prostate cancer (PCa) is one of the most common hormone-dependent cancers in men in Western and also Asian countries. The standard treatment options for localized PCa include surgery and androgen-deprivation therapy (ADT). However, most patients upon ADT therapy invariably relapse and progress to a more aggressive and metastatic stage termed as castration-resistant PCa (CRPC). Accumulating studies indicate that androgen receptor (AR) transcriptional activity is dysregulated during the advanced progression of CRPC. One important mechanism responsible for the growth of CRPC includes increased intra-tumoral androgen synthesis in PCa. Recently, a novel androgen-responsive fusion gene TMPRSS2:ERG formed by fusion between the transmembrane protein TMPRSS2 and transcription factor ERG, has been identified in approximately 50% PCa samples, which results in the aberrant expression of ERG function as oncogenic factor in PCa. Currently, TMPRSS2:ERG is regarded as a significant potential diagnostic and prognostic biomarker for PCa. Estrogen-related receptor alpha-ERRα, the first identified ligand-independent orphan nuclear receptor, is characterized to be up-regulated in advanced cancers, suggesting that ERRα might play important regulatory roles in the malignant progression of PCa. Previous studies showed that ERRα can functionally cross-talk with AR signaling via co-targeting to AR targets and regulate the expression of some steroidogenic enzymes in breast cancer. Based on this background, it is hypothesized that ERRα could functionally regulate the TMPRSS2:ERG fusion gene and play a regulatory role in the development and progression of CRPC through activation of the intracellular androgen synthesis pathway. / Results. 1) The results obtained in this study showed that suppression of ERRα by its specific inverse agonist XCT790 or shRNA-knockdown could induce down-regulation of TMPRSS2:ERG and also its target genes in AR-positive VCaP PCa cells. 2) Ectopic expression of ERRα and/or its coactivator PGC-1α could increase the expression of TMPRSS2:ERG in AR-negative NCI-H660 PCa cells. 3) Two ERRα-DNA binding elements were identified by ChIP assay and sequence analysis in the promoter of TMPRSS2:ERG and both of these two elements could be transactivated by ERRα and PGC-1α. 4) Ectopic expression of TMPRSS2:ERG under the regulation of ERRα enhanced the prostatic cell invasion capacity as shown in the TMPRSS2:ERG infectants of BPH-1 and PC-3 prostatic cells. 5) ERG expressed by the TMPRSS2:ERG fusion could directly transactivate the ERRα gene in prostatic cells. 6) A positive correlation on the expressions between TMPRSS2:ERG and ERRα was demonstrated in a xenograft model of CRPC (VCaP-CRPC). 7) The expression of TMPRSS2:ERG and ERRα showed significant up-regulation and the transactivation activity of ERRα was also enhanced in castration-resistant VCaP-CRPC cells. 8) Ectopic expression of ERRα could promote resistant growth capacity to androgen-deprivation condition in LNCaP PCa cells, whereas shRNA-mediated silence of ERRα could weaken this resistant capacity. Furthermore, ectopic expression of ERRα in LNCaP-ERRα infectants could promote their in vivo growth resistance to castration in SCID mice. 9) Expression of several androgenic enzyme genes, including CYP11A1, CYP17A1 and ARK1C3, were detected to be up-regulated in castration-resistant VCaP-CRPC cells. Moreover, ectopic expression of ERRα could induce the increased expression of these enzyme genes in LNCaP-ERRα infectants, whereas knockdown of ERRα by shRNA could decrease their expression. 10) ERRα could directly transactivate the gene promoters of CYP11A1, CYP17A1 and ARK1C3 which contain ERRE elements prediction by sequence analysis. These results suggested that ERRα could play a role in de novo or intra prostatic androgen synthesis in the PCa cells. / Conclusions. The results obtained in this study suggested that ERRα and TMPRSS2:ERG could form a positive reciprocal loop in PCa cells, and ERRα could also promote the resistant growth capacity of PCa cells resistant to the androgen-deprivation condition in vitro and also castration-resistant growth in vivo via a mechanism of up-regulation of androgenic enzyme genes. The results also suggested that ERRα might play a significant regulatory role in the development and progression of PCa, particularly the advanced CRPC, and also ERRα could be a potential therapeutic target for the treatment of PCa, particularly the advanced PCa-CRPC. / 研究背景與研究目的：前列腺癌作為激素依賴的一種癌症，經常出現在西方和亞洲國家的男性人群中。對於局限性前列腺癌多採用外科手術和去勢的治療。但是大多數病人經過去勢治療后會再次復發並且形成更加惡心幾轉移的前列腺癌，稱之為去勢難治性前列腺癌（CRPC）。越來越多的研究表明在去勢難治性前列腺癌發病過程中，雄激素受體轉錄活性異性增強。其中一個重要機理解釋為前列腺癌細胞自身合成的雄激素增多。進來，在大約50%的前列腺癌病人中新檢測到一個受雄激素受（AR）體調控的融合基因TMPRSS2:ERG，它是由稱為TMPRSS2的一個跨膜蛋白和一個稱為ERG的轉錄因子融合而成，它的出現導致了在前列腺癌中異常的稱為致癌因子的ERG蛋白的高表達。目前，TMPRSS2:ERG已經被作為一個重要的潛在的診斷和預測的標誌物應用在前列腺癌中。作為第一個鑒定的配體不依賴的孤兒受體-ERRα，被證明在晚期的癌症中有很高的表達，預示著ERRα可能在惡性的癌症中起到一個非常重要的調控作用。之前的研究表明通過共同調控AR的下游基因，ERRα同AR信號通路之間有功能性的交叉調控；除此之外，在乳腺癌中，ERRα還可以調控一些類固醇類化合物的合成相關的一些酶的合成。依據上述，我們推定ERRα可能功能性地調控TMPRSS2:ERG融合基因的表達並且通過調控細胞內的雄激素的合成進而在去勢難治性前列腺癌的發生和發展中起到一個非常重要的作用。 / 結果：本論文研究結果總結如下：1）在有AR表達的前列腺癌細胞-VCaP細胞中，通過ERRα特異性的抑制劑XCT790處理或者shRNA介入的干擾ERRα的mRNA的方法來抑制ERRα，下調了TMPRSS2:ERG和它的一些下游調控基因的表達。2）在沒有AR表達的前列腺癌細胞-NCI-H660細胞中，上調ERRα或者它的特異性的共激活因子PGC-1α表達可以提升TMPRSS2:ERG的表達。3）通過ChIP實驗，在TMPRSS2:ERG的啟動子上面，兩個ERRα的DNA結合位點被鑒定出來。並且這兩個位點可以被ERRα和PGC-1α轉錄激活。4）在兩個前列腺細胞BPH-1和PC-3細胞中，在ERRα的調控下高表達TMPRSS2:ERG融合基因可以增強細胞的侵襲能力。5）融合基因TMPRSS2:ERG導致的ERG蛋白的表達可以直接轉錄激活ERRα的表達。6）我們通過VCaP細胞的異種移植建立VCaP-CRPC的體內模型來模擬CRPC過程，在整個過程中，我們發現TMPRSS2:ERG和ERRα有一致性的表達相關性。除此之外，我們根據上述動物模型通建立了VCaP-CRPC細胞系，並且發現在VCaP-CRPC細胞細胞中，TMPRSS2:ERG和ERRα都有被上調並且ERRα的轉錄活性同樣也提升。7）在LNCaP細胞中高表達ERRα可以提升細胞在去除雄激素的環境中生長的能力。但是當在LNCaP細胞中用shRNA干擾掉ERRα可以明顯減弱這種生長的能力。用LNCaP-ERRα穩轉ERRα的細胞異種移植建立SCID老鼠體內腫瘤模型，我們發現和LNCaP-pBABE對照組相比，LNCaP-ERRα細胞生長的更快更大。並且在對老鼠進行睪丸切除術后，LNCaP-ERRα組細胞更快適應這種環境并繼續生長，相比之下，LNCaP-pBABE對照組則持續萎縮減小。8）在上述的VCaP-CRPC細胞中，我們發現一些和雄激素合成相關的關鍵的酶包括CYP11A1，CYP17A1和ARK1C3的表達量有顯著地提升。而且在LNCaP-ERRα細胞中同樣檢測到這些酶的表達量的提升。然而當在LNCaP細胞中用shRNA干擾掉ERRα可以明顯減降低上述酶的表達。9）我們在CYP11A1，CYP17A1和ARK1C3基因的啟動子區域發現有ERRα結合位點，並且發現這些位點可以被ERRα轉錄激活。 / 結論：本論文的研究結果提示在前列腺癌細胞中，ERRα和TMPRSS2:ERG可以形成一個相互正向調控的循環。除此之外，上調ERRα可以促進細胞在去除雄激素的環境中生長的能力，並且在動物體內可以提升細胞在睪丸去除的環境中的適應和生長能力。這種體內和體外的能力的提升是通過一種潛在的上調前列腺癌細胞的雄激素合成相關的關鍵的酶的表達，進而提升雄激素的含量而得以實現的。上述的結果預示著ERRα可能在前列腺癌發生機發展的過程中起到非常重要的調控作用，尤其在晚期的CRPC中。同時，ERRα也可能作為一個潛在的重要的前列腺癌尤其是晚期的CRPC的治療靶點，尤其是一些潛在ERRα的特異性抑制劑，比如XCT790，可能作為將來用以作為治療前列腺癌的特異性靶點藥物。 / Xu, Zhenyu. / Thesis Ph.D. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 126-143). / Abstracts also in Chinese. / Title from PDF title page (viewed on 05, October, 2016). / Xu, Zhenyu. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

A tomografia por emissão de pósitrons associada à tomografia computadorizada (PET/CT) é um dispositivo que combina as características de medicina nuclear (PET) e de radiologia (CT) obtendo imagens metabólicas (PET) e anatômicas sobrepostas (CT). Combinando as duas tecnologias de exames, o exame PET / CT permite aos médicos diagnosticar com maior precisão e identificar o câncer, doenças cardíacas e distúrbios cerebrais. O radiofármaco 18FFAc (fluoroacetato) é promissor para a detecção de tumores primários de próstata e de mama, utilizando a técnica de PET/CT. Estudos recentes mostram a eficácia do 18F-FAc na detecção de tumores que têm baixa captação de 18F-FDG (fluordesoxiglicose). O fluoroacetato é um substrato para a acetil-CoA sintase, enzima que metaboliza ácido fluorocitrato que não é mais metabolizado, levando à inibição da aconitase e do ácido tricarboxílico. O objetivo deste trabalho foi desenvolver um radiofármaco emissor de pósitron, 18F-FAc no IPEN-CNEN/SP em um acordo com o Hospital AC-Camargo / São Paulo. O íon fluoreto (18F-) foi produzido, usando os cíclotrons Cyclone 30 e 18 da IBA localizados no IPEN-CNEN/SP, através da irradiação de água enriquecida em 18O com prótons e dose integrada de 30&mu;Ah. A marcação do 18F-FAc foi realizada em um módulo de síntese TRACERlab MXFDG (GE), utilizando kits adquiridos da ABX. O controle de qualidade radioquímico de 18F-FAc foi realizado por cromatografia em camada fina TLC-SG 25 folhas de alumínio em tiras (1,5 x 12 cm ) usando como solvente clorofórmio:metanol (1:1). Para o controle de qualidade radionuclídico, amostras de 18F-FAc e 18F-Fluoreto foram analisadas por espectroscopia de raios-gama. A avaliação dos solventes residuais foi realizada por cromatografia em fase gasosa e a análise de kryptofix foi realizada por TLC utilizando tiras de TLC-SG, metanol:clorofórmio (9:1) como solvente e padrões de kryptofix 2.2.2. Os estudos de biodistribuição foram realizados com 18FFAc injetado em camundongos swiss sadios. Um procedimento reprodutível foi desenvolvido para o preparo do 18F-FAc com um rendimento de marcação de 37% (não corrigido) e 52% (corrigido para o decaimento) e estabilidade de 19 horas. A análise de controle de qualidade mostrou que o produto tinha as exigências adequadas para utilização, com pureza radioquímica superior a 99,9%. Os estudos de biodistribuição em animais sadios mostraram a esperada captação em todos os órgãos medidos com eliminação renal e intestinal. / PET / CT (positron emission tomography / computed tomography) is a device that combines the features of diagnostic nuclear medicine (PET) and Radiology (CT) superimposing metabolic (PET) and anatomical (CT) images. By combining the two technologies examinations, the PET/CT scan allows physicians to diagnose more accurately and identify cancer, heart disease and brain disorders. The radiopharmaceutical 18F-FAc (fluoroacetate) is promising for application in detection of primary tumors of prostate and breast, using PET-CT techniques. Recent studies are showing the efficacy of the 18F-FAc in the detection of tumors that have low uptake of 18F-FDG (fluorodeoxyglucose). The fluoroacetate is a substrate for the enzyme acetyl-CoA synthase that metabolizes acid fluorcitric that, not being metabolized, causes inhibition of aconitase and inhibition of tricarboxylic acid. The aim of this work was to develop a positron emitting radiopharmaceutical, 18F-FAc at IPEN-CNEN/SP in agreement with Hospital AC-Camargo/ São Paulo. The 18F-fluoride ion was produced using the Cyclone 30 and 18 cyclotrons from IBA located at IPEN-CNEN/SP, by irradiating enriched 18O water with protons with integrated dose 30&mu;Ah. The labelling of 18F-FAc was performed in a synthesis module TRACERlab MXFDG (GE), using kits purchased from ABX. The radiochemical quality control of 18F-FAc was performed by Thin Layer Chromatography using TLC-SG 25 aluminium sheets strips (1.5 x 12 cm) and chloroform:methanol (1:1) as the solvent. For the radionuclidic quality control, samples of 18F-FAc and 18F-Fluoride were analysed by gama-ray spectroscopy. The evaluation of the residual solvents was performed by gas chromatography and the analysis of kryptofix was performed by TLC using TLC-SG strips, methanol:chloroform (9:1) as solvent and kryptofix 2.2.2 standards. Biodistribution studies were performed with 18F-FAc injected into healthy Swiss mice. A reliable procedure was developed for preparation of 18F-FAc with a labelling yield of 37% (uncorrected) and 52% (corrected for decay) and stability of 19 hours. The quality control analysis showed that the product had the proper requirements for use, with radiochemical purity exceeding 99.9%. The biodistribution studies in healthy animals showed the expected uptake results in all the measured organs with intestinal and renal elimination.

INTRODUÇÃO: O câncer de próstata (CAP) é a neoplasia mais comum em homens (excluindo câncer de pele não-melanoma) com mais de 190.000 casos novos esperados em 2010 nos Estados Unidos sendo que mais de 27.000 morrerão em desta doença. No Brasil, segundo o Instituto Nacional do Câncer, a estimativa é em torno de 50 mil casos novos de CAP para 2010. OBJETIVOS: Avaliar a experiência do rastreamento para CAP realizado pelo Hospital de Câncer de Barretos através de uma Unidade Móvel de Prevenção de Câncer (UMPC), e verificar qual o impacto deste rastreamento no estádio clínico em comparação com pacientes diagnosticados e/ou encaminhados ao HCB. MATERIAL E MÉTODO: De janeiro de 2004 a dezembro de 2007, realizou-se rastreamento de CAP em voluntários acima de 45 anos através da UMPC em localidades com difícil acesso à saúde. Foram convocados homens com pelo menos um destes três critérios a seguir: a) PSA sérico = 4,0 ng/ml, b) toque retal suspeito, ou c) PSA entre 2,5 e 4,0 ng/ml com relação PSA livre/total (rPSAl/t) = 15%. Para se avaliar o impacto do rastreamento no estádio clínico ao diagnóstico dos pacientes portadores de CAP, analisaram-se os dois grupos. O grupo I inclui casos de CAP diagnosticados de janeiro de 2005 a dezembro de 2007, através da UMPC. O grupo II inclui pacientes com CAP atendidos pelo HCB no mesmo período, que não haviam feito diagnóstico pela UMPC; e foram encaminhados ao HCB por médicos de especialidades diversas, devido a PSA elevado e/ou TR suspeito realizado na xvii localidade de origem ou a diagnóstico histológico confirmado de CAP. A revisão de prontuários para os grupos realizou-se no serviço de arquivo médico (SAME) e utilizou-se a mesma ficha de coleta de dados, priorizando TNM, PSA e escore de Gleason. Os grupos I e II foram comparados com relação a estadiamento (TNM), PSA e escore de Gleason e feita análise estatística destes dados. RESULTADOS: De janeiro de 2004 a dezembro de 2007, foram rastreados 17.571 homens de 231 cidades brasileiras. Destes, 71,4% nunca tinham feito toque retal e 70,9% nunca fizeram PSA anteriormente. Foram biopsiados 1.647, 904 devido a PSA = 4,0 ng/ml (54,9%), 324 devido a TR suspeito (19,7%), 117 devido a alteração simultânea de ambos os anteriores (7,1%) e 302 quando a relação foi = 15% com PSA entre 2,5 e 3,9 ng/ml (18,3%). Foram diagnosticados 652 casos de CAP (3,7%). Destes, 609 (93,4%) clinicamente localizados (T1-2) e 43 (6,6%) foram T3-4. Na avaliação radiológica e cintilográfica, 26 (4%) eram N1 e 18 (2,8%) eram M1. Comparando-se os grupos, observou-se valores de PSA mais baixos (p<0.001), estadiamento clínico mais favorável (p<0,001), e escore de Gleason com menor grau para o grupo I (p<0.001). CONCLUSÕES: A UMPC mostrou ser uma ferramenta importante para se rastrear populações com acesso médico precário em um país com grande extensão territorial e desigualdades socioeconômicas como o Brasil. O rastreamento mostrou melhoria estatisticamente significativa do estadiamento clínico ao diagnóstico em relação aos pacientes diagnosticados na rotina do Hospital de Câncer de Barretos / BACKGROUND: Prostate cancer (PC) is as the most common neoplasm in men (excluding skin cancer non-melanoma) with more than 190,000 new cases expected in 2009 in the United States and more than 27,000 will die from the disease. In Brazil, according to the Brazilian National Cancer Institute, the estimate is almost 50.000 new cases for 2009. OBJECTIVES: To assess the experience of PC screening conducted by the Barretos Cancer Hospital (BCH) through a mobile cancer prevention unit (MCPU), and to verify the impact of screening on clinical stage compared with patients diagnosed and/or referred to the HCB. MATERIAL AND METHODS: From January 2004 to December 2007, a PC screening was applied to volunteers over 45 years old through a MCPU which reached Brazilian locations with difficult access to health. Men with at least one of the following three criteria were called for further evaluation: a) serum PSA level = 4.0 ng/ml, b) suspicious digital rectal examination (DRE), or c) PSA level of 2.5-4.0 ng/mL and a percent-free PSA (%fPSA) level =15%. To assess the impact of screening on clinical stage at diagnosis of patients screened and non-screened, the men were analyzed in two groups. The PC cases screened from January 2005 to December 2007 through the MCPU constituted Group I. Comprising group II, there was patients with PC treated by BCH in the same period, who hadnt been diagnosed by the MCPU. These patients in group II were referred to hospital by xix physicians of several specialties, mainly due to elevated serum PSA and/either suspicion DRE or histological diagnosis of PC. The data for both groups was held in the medical records and used the same form, prioritizing the data for the TNM staging, PSA and Gleason score. Groups I and II were compared with concern to staging (TNM), PSA and Gleason score and the statistical analysis of these data was performed. RESULTS: From January 2004 to December 2007, 17,571 men from 231 Brazilian cities were screened. Among them 71.4% had never been submitted to DRE examination and 70.9% never had a PSA test. 1,647 men were submitted to biopsy, 904 due to PSA = 4.0 ng/ml (54.9%), 324 due to suspicion DRE (19.7%), 117 due the simultaneous of both earlier (7.1%) and 302 with %fPSA level =15% and PSA between 2.5-3.9 ng/ml (18.3%). It were diagnosed 652 cases of PC (3.7%). Among them, 609 (93.4%) were clinically localized (T1- 2) and 43 (6.6%) were T3-4. In the image exams, 26 (4%) were N1 and 18 (2.8%) were M1. The comparison between both groups showed lower serum PSA values (p <0.001), more favorable clinical stage (p <0.001) and Gleason score in group I (p <0.001). CONCLUSIONS: The MCPU has proved to be an important tool in screening populations with poor medical access in a country with large territory and socioeconomic inequalities such as Brazil. The screening showed statistically significant improvement of clinical staging at diagnosis compared to patients diagnosed in the routine of the BCH