Background: Androgen deprivation therapy (ADT) has known adverse effects (AEs). Intermittent (INT) ADT may reduce AEs, improve quality of life, and lower costs compared to continuous (CONT) treatment. Objective: To evaluate the cost-effectiveness of INT vs CONT ADT in men with advanced prostate cancer. Methods: A lifetime Markov individual simulation model was developed to evaluate the incremental cost per quality adjusted life month (QALM) of INT vs CONT ADT. Results: INT dominated CONT ADT (mean total costs $94,460 vs $109,431; mean total QALMs 47.0 vs 46.4). INT ADT resulted in less time on therapy (22.4 vs 56.8 months), fewer hip fractures (0.080 vs 0.093 per patient), and fewer total cases of sexual dysfunction (72.5% vs 87.0% of patients) and cardiovascular disease (38.7% vs 44.6% of patients). Conclusions: These results suggest INT ADT is cost-effective compared to CONT ADT however, differences were small. Additional research is required to confirm these findings.

Metastases to bone are observed in around 80% of prostate cancer patients and represent the most critical complication of advanced prostate cancer. Unlike other solid tumors that are associated with osteolytic bone metastases, prostate cancer bone metastases stimulate osteoblastic activity with sclerosis in the bone lesions as a consequence. Osteoprotegerin (OPG) is part of a system with three proteins that play a key role in bone remodeling; namely OPG, RANK and RANKL. RANKL regulates osteoclast activity by binding to RANK on the osteoclasts surface, and this interaction is interrupted by OPG. OPG also plays a role in the lifecycle of tumor cells by blocking TNF-related apoptosis-inducing ligand (TRAIL) making it possible for them to evade cell death. The aim of this thesis was to investigate the interaction between the OPG/RANK/RANKL system and prostate cancer. Data showed that there was production of OPG from prostate cancer cell lines in vitro. This expression was under the influence of cytokines that are present in the microenvironment of bone. Further, there was documented a previously unnoticed cell surface expression of RANKL. Co-culturing the prostate cancer with human osteoblasts increased the expression of RANKL. To connect these findings with in vivo studies, OPG-gene single nucleotide polymorphisms (SNP) were investigated. To evaluate OPG SNPs association with bone, a cohort of elderly men was used. OPG SNPs was shown to be correlated to bone mineral density at hip and spine. There was also an association to fragility fractures. Then there was examined the association of the same SNPs to the incidence of prostate cancer but after a four-year follow-up there was no association to the genetic variants. To summarize this research, we hereby present data that the OPG/RANK/RANKL system might be relevant for prostate cancer growth in bone, and for the skeletal related morbidity in this disease. Future in vitro and in vivo studies will demonstrate the relative importance of this crosstalk, and whether pharmacological interference with the system might be used as a therapeutic tool aiming to decrease skeletal morbidity and possibly also prolong survival in prostate cancer.

This work presents an investigation of the potential development of phenoxodiol, a novel isoflavone, for the treatment of prostate cancer. The literature concerning isoflavone epidemiology, pharmacology, clinical use and their effect on prostate cancer is reviewed. Isoflavone impact on signal transduction pathways is also reviewed with a particular focus on the Akt / mTOR signal transduction pathway, a key signaling pathway in prostate cancer cells. In vitro experiments and xenograft nude mice studies show that phenoxodiol inhibits the growth of DU145 and PC3 prostate cancer cells, when used alone and in combination with cisplatin or carboplatin. Phenoxodiol in combination with cisplatin is highly synergistic when inhibiting the growth of DU145 cells in particular. We show for the first time, that phenoxodiol and cisplatin or carboplatin, inhibits phosphorylation of Akt and mTOR in DU145 and PC3 cells. A first-in-human study of single dose phenoxodiol investigating its pharmacokinetic properties in cancer patient volunteers was performed. Extensive conjugation of phenoxodiol and a short half-life was noted in this study. A Phase I study of intravenous phenoxodiol administered weekly to patients with advanced cancer was then performed to assess toxicity of a repeated dose schedule, as well as the maximum tolerated dose. This schedule was well tolerated in patients, with lymphocytopenia noted as the main toxicity. Given the short half-life of phenoxodiol and our preclinical studies suggesting that combination with cisplatin and carboplatin synergistically inhibited prostate cancer cell growth, we also undertook a Phase I dose escalation study of oral phenoxodiol administered in combination with cisplatin or carboplatin to patients with advanced cancer. The main adverse events include hyperglycemia, hypocalcemia, mild transaminase rises, as well as nausea, constipation, infusion site reactions and lethargy. Three patients with ovarian cancer responded to treatment according to CA125 criteria, and there was a 45% reduction in prostate specific antigen level in one man with androgen independent prostate cancer. The bioavailability of the oral formulation of phenoxodiol was calculated to be 17.5%. Phenoxodiol shows promise for further development in the potential treatment of prostate cancer.

This work presents an investigation of the potential development of phenoxodiol, a novel isoflavone, for the treatment of prostate cancer. The literature concerning isoflavone epidemiology, pharmacology, clinical use and their effect on prostate cancer is reviewed. Isoflavone impact on signal transduction pathways is also reviewed with a particular focus on the Akt / mTOR signal transduction pathway, a key signaling pathway in prostate cancer cells. In vitro experiments and xenograft nude mice studies show that phenoxodiol inhibits the growth of DU145 and PC3 prostate cancer cells, when used alone and in combination with cisplatin or carboplatin. Phenoxodiol in combination with cisplatin is highly synergistic when inhibiting the growth of DU145 cells in particular. We show for the first time, that phenoxodiol and cisplatin or carboplatin, inhibits phosphorylation of Akt and mTOR in DU145 and PC3 cells. A first-in-human study of single dose phenoxodiol investigating its pharmacokinetic properties in cancer patient volunteers was performed. Extensive conjugation of phenoxodiol and a short half-life was noted in this study. A Phase I study of intravenous phenoxodiol administered weekly to patients with advanced cancer was then performed to assess toxicity of a repeated dose schedule, as well as the maximum tolerated dose. This schedule was well tolerated in patients, with lymphocytopenia noted as the main toxicity. Given the short half-life of phenoxodiol and our preclinical studies suggesting that combination with cisplatin and carboplatin synergistically inhibited prostate cancer cell growth, we also undertook a Phase I dose escalation study of oral phenoxodiol administered in combination with cisplatin or carboplatin to patients with advanced cancer. The main adverse events include hyperglycemia, hypocalcemia, mild transaminase rises, as well as nausea, constipation, infusion site reactions and lethargy. Three patients with ovarian cancer responded to treatment according to CA125 criteria, and there was a 45% reduction in prostate specific antigen level in one man with androgen independent prostate cancer. The bioavailability of the oral formulation of phenoxodiol was calculated to be 17.5%. Phenoxodiol shows promise for further development in the potential treatment of prostate cancer.

Currently, there are no preclinical immunocompetent mouse models that adequately represent all stages of prostate cancer (PC) especially, androgen depletion independent (ADI) and bone metastatic PC. The best characterized, Transgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model is logistically a difficult model for in vivo assessments and it does not adequately represent all stages of PC. Therefore, the aim of this study was to broaden the TRAMP model to include ADI and bone metastatic PC. Three ADI sublines were derived from androgen-sensitive (AS) TRAMP C1 (TC1) and TRAMP C2 (TC2) parental lines in vitro by dihydrotestosterone (TC1-T5 and TC2-T5) deprivation and in vivo by growing in TRAMP female mice (TC1-F1). The new sublines showed several characteristic features of ADI-PC 1.) faster growth rates in vitro and in vivo 2.) increased invasiveness 3.) androgen depletion independence in vitro and in vivo 4.) variable expression of androgen receptor 5.) downregulation of metastasis suppressor genes, E-cadherin and KAI-1. Genetic and molecular studies of ADI sublines showed alteration of genes representing major cancer related pathways. ADI TC1-T5, that displayed the most aggressive phenotype/genotype was selected to expand the TRAMP model to represent PC metastases Metastatic ability of TC1-T5 to migrate to bone and other soft tissues after intracardiac injections was shown in contrast to AS TC1 cells. Bone metastatic lesions displayed both osteoblastic and osteolytic features in multiple locations. Additionally, unlike AS TC1, the TC1-T5 tumours were able to grow with 100% incidence in the prostate and as lungs pseudometastases. The ADI PC lines were used to explore Aurora Kinases (AKs) as therapeutic targets for ADI PC. Compared to TC1, ADI-TC1-T5 cells showed a significant upregulation of AK-A and AK-B and their downstream regulators, survivin and phosphorylated-histone H3. Enhanced sensitivity of TC1-T5 to AK inhibitor VX680 functionally validated this and together with docetaxel led to enhanced efficacy which correlated with implication of AK-A/B in development of docetaxel-resistance. Thus, TRAMP model now represents ADI-PC that can grow in the bone, lungs and in the prostate; a significant step towards a well rounded preclinical model with greater clinical relevance.

[Truncated abstract] Purpose: Permanent prostate brachytherapy (PPB) as a treatment option for prostate cancer requires implantation of 80-150 radioactive iodine-125 (I-125)

It has been shown that tumour cells are capable of switching to glycolytic metabolism for the production of ATP even in the presence of oxygen, this is known as aerobic glycolysis or the 'Warburg effect'. The glycolytic phenotype has been associated with tumour aggressiveness and poor outcome in several cancer types. This makes the area of cancer metabolism an attractive area for the potential identification of new therapeutic targets. One key component, required for cells to maintain the glycolytic phenotype, is the presence of monocarboxylate transporters that are capable of exporting lactate. These transporters are vital for the maintenance of the intracellular pH of cells under these conditions. This study was centred around the hypothesis that altering expression of MCTs would impact on the metabolism of tumour cells and, therefore, other key characteristics of cells relating to metastatic capabilities and survival following treatment. For the purpose of this work, prostate cancer cell lines were transfected with lentiviral particles targeting overexpression of MCT1 or MCT4, or knockdown of MCT4. Following transfection, cellular metabolic profiles were assessed under normoxic and hypoxic conditions and the metastatic phenotype of each cell line was investigated. Additionally, the effect of MCT expression on response to chemotherapy and radiation therapy was explored, and a siRNA metabolome screen was performed to identify combinations of targets that may produce synthetic lethality in prostate cancer cell lines. It was shown that changes in the expression of MCT1 or MCT4 did not cause significant changes in the metastatic phenotypes of the prostate cancer cell lines investigated. Some differences were observed in the metabolic pathways used by these prostate cancer cells following alterations in MCT expression. For example, overexpression of MCT1 in DU145 cells resulted in an increase in intracellular lactate. Additionally, MCT4 knockdown in PC3 cells was able to reduce OXPHOS under reduced oxygen. MCT1 overexpression was able to sensitise androgen-independent prostate cancer cells to treatment with chemotherapy and radiation therapy. Furthermore, combinations of siRNA treatments were identified that may be capable of producing synthetic lethality. In summary, findings in this study indicated that targeting MCT1 and MCT4 expression could offer therapeutic benefit in prostate cancer. However, it was also highlighted that the roles of these transporters are specific to cancer type, and even cell line.

In the US, the incidence and mortality rates of prostate cancer (PCa) are higher among African American men compared to European American men. Obesity is an important risk factor of PCa. Obesity is known to alter the gene expression profiles in prostate tumors. This study evaluates the impact of obesity and the expression of obesity-related genes on the progression of PCa in African American men. The primary outcome of interest is biochemical recurrence (BCR) of PCa. There were 48 African American prostate cancer patients in the study. The tissue samples included 42 normal tissues, 40 Prostate Intraepithelial Neoplasia (PIN) and 45 tumor tissues (127 tissue samples in total). We assembled 99 obesity-related genes and determined the levels of their expression in the three types of tissue samples using Nanostring Technologies. An ANOVA test was used to compare the means for gene expression among normal, PIN and tumor tissue samples. Unconditional logistic regression models were used to calculate odds ratios (ORs) and their respective 95% confidence intervals (95% CIs) to determine the association between obesity and BCR as well as gene expression and BCR. Results were regarded as statistically significant if p-values were less than 0.05. A Kaplan Meier Curve was constructed to depict the survival time and time to event (BCR) among obese and non-obese African American prostate cancer patients. Patients were followed up from the date of first surgery to the date of biochemical recurrence or date of last follow-up. Statistical analysis was done with SAS 9.4 software. Forty-three obesity-related genes were statistically significantly associated with biochemical recurrence. There was no association between obesity and biochemical recurrence (BCR) in obese African American men compared to non-obese African American men (OR= 2.03, 95% CI = 0.22 - 18.77, p-value= 0.53). Twenty genes showed an upward trend in gene expression among normal, PIN and tumor tissue samples including ADIPOR1, AKRIC4, ALOX12, ALOX15, CRYBB2, EIF5A, ERG, GNPDA2, HNF1B, HSD3B1, KLK4, LEP, MC4R, MTCH2, PCSK1, PIK3CB, SLC2A2, STAT1, SULT1A1, YY1. The probability of survival (not having BCR) is lower in obese African American men compared to non-obese African American men as indicted in the Kaplan Meier curve. In other words, the probability of developing BCR is higher in obese African American men compared to non-obese African American men. We did not find a significant association between obesity and biochemical recurrence. However, we elucidated some obesity-related genes that could explain PCa carcinogenesis. Further studies are needed to determine functional significance of these selected obesity-related genes and the role they play in encouraging PCa progression in African American men.

Objetivo: Analisar a casuística de prostatovesiculectomias radicais com linfadenectomia ilíaca avaliando a validade das Tabelas de Partin versão 2001. Estudar variáveis que possam interferir no confinamento ou não da neoplasia como retardo cirúrgico, peso prostático, resultados referentes à biópsia e ano da cirurgia. Material e Métodos: Avaliação retrospectiva de 568 prontuários de pacientes submetidos à cirurgia para câncer de próstata clinicamente localizado entre 1995 até agosto de 2005 no Hospital de Clínicas de Porto Alegre. Foram excluidos quem tivesse feito hormonioterapia neoadjuvante ou com diagnóstico feito por ressecção endoscópica da próstata e aqueles com insuficiência dos dados no prontuário. Estágio clínico pelo toque retal , valores de PSA e dados da biópsia que diagnosticou a neoplasia, assim como dos dados da peça da prostatectomia radical foram coletados. Os valores preditivos das Tabelas de Partin, versão 2001 foram comparados com os do espécime cirúrgico e analisados através de Curvas R.OC. Foram também avaliados tempo de espera para cirurgia, peso da próstata, ano da cirurgia, uni ou bilateralidade tumoral na biópsia e qual a biópsia que diagnosticou (primeira ou ulterior) e analisados como fatores preditivos para confinamento ou não da neoplasia. Resultados: A idade média do pacientes foi 63 (42-77). A percentagem de estágio T1c foi de 63 %. Pacientes com escore de Gleason 2-4 na biópsia constituiram 20,2 %, notadamente antes de 2000. O percentual de pacientes com níveis de PSA menores de 4,0 ng/ml foi de 8,3 % e acima de 10,0 ng/ml foi de 35 %. Os percentuais de doença confinada ao órgão, extensão extra-prostática, invasão de vesículas seminais e metástases linfonodais foram 48,2 %, 35,3%, 13,9% e 2,6% , respectivamente. A área sob a curva calculada para doença confinada ao órgão foi de 0,65 , enquanto as áreas sob as curvas para extensão extra-prostática, invasão de vesículas seminais e metástases linfonodais foi respectivamente 0,54; 063 e 0,77. Pacientes que tiveram o diagnóstico já na primeira biópsia, ou com biópsias bilateralmente comprometidas e aqueles operados antes de 2000 tinham tendência ao não confinamento. Biópsias realizadas a partir de 2000 que já foram positivas na primeira tentativa tiveram maior tendência ao confinamento do que até 1999. Conclusão: As Tabelas de Partin tiveram valor preditivo marginal para as características patológicas finais como doença confinada ao órgão e invasão de vesículas seminais e valor preditivo importante para metástases linfonodais. Não mostraram valor preditivo para extensão extra-prostática. Bilateralidade tumoral na biópsia, diagnóstico na primeira biópsia (especialmente até 1999) e cirurgia antes de 2000 configuraram situações com tendência a tumores não confinados. / Objective: The predictive value of current Partin tables (2001) has been not validated in most of the countries as well Brazil. Therefore, we evaluated the validity of 2001 Partin tables for the ability to predict the pathological stage in specimens of radical prostatectomy. Also, we analysed how biopsies can predict results for organ confinement or not and as well what the year of the surgery can make in organ confinement issue . Materials and methods: The clinical and pathological findings of 568 patients who have had radical prostatectomy and iliac lymphadenectomy from 1995 to 2005 at Hospital de Clínicas de Porto Alegre were assessed. Those with missing information, patients who had neoadjuvant endocrine treatment and those who had the diagnosis by transurethral ressection of prostate were excluded. Serum PSA, clinical stage, biopsy characteristics and the pathological features of the specimens were collected. The predictive value of Partin tables and pathological findings of prostatectomy specimens were compared and analyzed according to Receiver Operating Characteristics curves. The delay of the surgery, prostate weight, year of the surgery, bilaterality of the biopsies and if the diagnostic biopsy was the first or not were important for the organ confined disease were also tested. Results: Median age of the patients was 63(42-77). The percentage of patients with clinical stage T1c was 63%. Gleason score 2-4 in biopsy constituted 20,2 %, at mainly before 2000. The ratio of patients with serum PSA above 4,0 ng/ml was 8,3% and higher than 10,0 ng/ml was 35%.Organ confined disease, extra-prostatic extension, seminal vesicle involvement and lymph node metastasis were 48,2%; 35,3%; 13,9 % and 2,6% respectively. Area under curve (AUC) values for organ confined disease, extra-prostatic extension, seminal vesicle invasion and lymph node involvement were 0,65 ; 0,54; 0,63 and 0,77. Tumor bilaterallity at biopsy and positive biopsy at the first procedure (at least until 1999) as well radical prostatectomy before 2000 were predictors for non organ confined prostate cancer. Conclusion: Partin tables have a marginally predictive value for the pathological features like organ confined disease and seminal vesicle involvement and a good predictive value for lymph node metastasis prediction. They don’t have predictive value for extra-prostatic extension. Positive first biopsy, bilateral tumor at biopsy and radical prostatectomy before 2000 were predictive for non organ confined disease.

Com o aumento da expectativa de vida no Brasil e a possibilidade de detecção precoce através de programas de rastreamento, o câncer de próstata, tem sido considerado um problema de saúde pública. Em um programa de rastreamento voluntário realizado no Hospital de Clínicas de Porto Alegre entre os anos de 1996 e 2000, 3.056 pacientes foram submetidos a um estudo transversal com o objetivo de determinar a prevalência e características do câncer de próstata na amostra. Para a análise estatística foi utilizado o teste qui-quadrado com nível de significância de p < 0,05.A idade média da amostra foi de 60,4 anos e a prevalência do câncer de próstata foi de 2,61%, sendo crescente com o aumento da idade. A sensibilidade e especificidade do PSA foram, respectivamente, 93,8% (IC = 85,4% a 97,7%) e 82,5% (IC = 81,1% a 83,8%), utilizando como ponto de corte do PSA o valor de 4ng/ml. O toque retal apresentou sensibilidade de 60% (IC = 48,4% a 70,6%) e especificidade 83,3% (IC = 81,9% a 84,6%). O número de biópsias realizadas para se diagnosticar um paciente com câncer de próstata foi de 11,9 e variou conforme a faixa etária. No estadiamento clínico, 51,3% dos pacientes eram T1C e 83,75% dos tumores estavam clinicamente confinados ao órgão. Enquanto estudos prospectivos e randomizados que tenham como desfecho a mortalidade não definirem o real papel do diagnóstico precoce do câncer depróstata, os programas de rastreamento devem ser realizados. Este estudo vem ao encontro da necessidade de conhecer a distribuição e as características da doença nas diversas regiões do país. / With the increase in life expectancy in Brazil and the possibility of early detection through screening programs, prostate cancer is being considered a public health problem. In a voluntary screening program performed in Hospital de Clínicas de Porto Alegre between the years of 1996 and 2000, 3,056 patients participated in a cross sectional study with the objective of determining the prevalence and features of prostate cancer in the sample. For statistical analysis, qui square test was performed considering a significance level of p < 0.05. The mean age of the sample was 60.4 years, and the prevalence of prostate cancer was 2.61%, increasing with age. The sensitivity and specificity of PSA were, respectively, 93.8% (CI = 85.4% to 97.7%) and 82.5% (CI = 81.1% to 83.8%) considering 4 ng/ml as the cut-off point for PSA. Rectal examination had a sensitivity of 60% (CI = 48.4% to 70.6%) and a specificity of 83.3% (CI = 81.9% to 84.6%). The amount of biopsies performed for diagnosing a patient with prostate cancer was 11.9 and varied according to age. In clinical staging, 51.3% of patients were T1C and 83.75% of tumors were clinically confined to the organ. While prospective and randomized trials with mortality as the endpoint do not define the real role of early diagnosis in prostate cancer, screening programs should be performed. This study meets the need for knowing the distribution and characteristics of the disease in the different regions of the country.