Latin American Challenges and Recommendations for Poly Adenosine Diphosphate Ribose Polymerase Inhibitor Treatment in Metastatic Castration Resistant Prostate Cancer: An Expert Overview.

In Latin America, prostate cancer is the third most common cancer overall and the most common in men, with the highest mortality rate of all cancers. In 2022, there were approximately 22,985 new prostate cancer cases and 61,056 deaths from prostate cancer in the region. Patients with metastatic disease that is resistant to cure by castration now have multiple therapeutic options, including poly-ADP ribose polymerase inhibitors. These treatment advances present new challenges, such as developing monitoring protocols for early detection of disease progression to castration resistance. The Americas Health Foundation organized a 3-day meeting with 8 regional oncologists and pathologists to create a paper on metastatic castration-resistant prostate cancer diagnosis and therapy, including the new poly-ADP ribose polymerase inhibitors. The panel examined metastatic castration-resistant prostate cancer in Latin America and recommended ways to improve patient care using published literature and their expertise. Gene mutations play an important role in prostate cancer development. Precision medicine innovations highlight the importance of genotyping DNA variants and tumor biomarkers for targeted treatment. Access to appropriate genetic testing is difficult, medications are available but expensive, and there is a lack of infrastructure and regulatory frameworks that prevent patients from benefiting from innovative therapies. The panel recommends developing a population database and biobank and creating tumor tissue collection, processing, and storage facilities. Multi-stakeholder collaboration is needed to integrate the information gathered, train staff, select target populations, improve patient accessibility, and reduce the cost burden of drugs, genetic counselors, and cancer geneticists in Latin America. Collaboration is essential among healthcare professionals, policymakers, patient advocacy groups, pharmaceutical companies, and international organizations to address these challenges and needs in Latin America.

Recommendations from the Galician Oncological Society and the Galician Society of Nuclear Medicine for the use of 177Lu-PSMA-617 radioligand-therapy in prostate cancer.

Theragnostic is a type of precision medicine that uses molecules linked to radioactive isotopes for the diagnosis and treatment of diseases. In recent years, it has gained significant importance to treat neuroendocrine tumors and is currently being used in prostate cancer. Various radiopharmaceuticals have emerged for diagnosing and detecting lesions showing prostate-specific membrane antigen (PSMA) positivity on the Positron emission tomography/computed tomography scan, being the most widely used labeled with [68Ga] and [18F]. Its use as therapy in prostate cancer (PC) has been assessed in the VISION, TheraP, and PSMAfore clinical trials conducted with the radioligand [177Lu]Lu-PSMA-617, demonstrating significant antitumor activity. The aim of this article is to present practical recommendations, based on current available scientific evidence and on a multidisciplinary consensus, for the diagnosis and treatment with [177Lu]Lu-PSMA-617 in patients with PC.

The Circulating miR-107 as a Potential Biomarker Up-Regulated in Castration-Resistant Prostate Cancer.

Prostate cancer (PCa) is a prevalent malignancy in men globally. Current diagnostic methods like PSA testing have limitations, leading to overdiagnosis and unnecessary treatment. Castration-resistant prostate cancer (CRPC) emerges in some patients receiving androgen deprivation therapy (ADT). This study explores the potential of circulating microRNA-107 (miR-107) in liquid biopsies as a prognosis tool to differentiate CRPC from non-castration-resistant PCa (NCRPC). We designed a case-control study to evaluate circulating miR-107 in serum as a potential prognosis biomarker. We analyzed miR-107 expression in liquid biopsies and found significantly higher levels (p < 0.005) in CRPC patients, compared to NCRPC. Notably, miR-107 expression was statistically higher in the advanced stage (clinical stage IV), compared to stages I-III. Furthermore, CRPC patients exhibited significantly higher miR-107 levels (p < 0.05), compared to NCRPC. These findings suggest that miR-107 holds promise as a non-invasive diagnostic biomarker for identifying potential CRPC patients.

Comparative effectiveness of first-line systemic treatments for metastatic castration-resistant prostate cancer: a systematic review and network meta-analysis.

OBJECTIVES: No head-to-head trials had been performed to estimate the relative effectiveness of poly ADP-ribose polymerase inhibitor (PARPi) and androgen receptor signaling inhibitor (ARSi) in the first-line treatment for metastatic castration-resistant prostate cancer (mCRPC). We aimed to perform a systematic review and network meta-analysis to evaluate the comparative effectiveness of various systemic treatment agents for patients with mCRPC. METHODS: A comprehensive literature search was conducted for abstracts and full-text articles from the database's inception through April 27, 2023. The study concentrated on assessing radiographic progression-free survival (rPFS) for both overall and homologous recombination repair mutation (HRRm) population, with overall survival (OS) as the secondary measure. Under the Bayesian framework, the overall effect was pooled using the fixed-effects model in base case analysis. Scenario analysis using restricted mean survival time (RMST) methods was performed to test the robustness of the results. RESULTS: Nine studies with 6,830 patients and 8 unique treatment options were included. Network meta-analysis demonstrated that talazoparib in combination with enzalutamide (TALA + ENZA; overall population, hazard ratio [HR], 0.20; 95% credible interval [CrI]: 0.16-0.26; RMST, 3.51; 95% confidence interval [CI] 2.46-4.60; HRRm population, HR, 0.15; 95% CrI: 0.09-0.23; RMST, 4.14; 95% CI 2.84-5.39) was superior to other treatments in the first-line setting in terms of rPFS. The results of Bayesian framework and RMST models showed consistent efficacy ranks. When extrapolated to overall survival benefit, within the Bayesian framework, olaparib plus abiraterone acetate and prednisone (OLAP + AAP) achieved the highest OS benefit for the overall population, which was not statistically significant when compared to TALA + ENZA. However, TALA + ENZA achieved the highest OS benefit at 3 years by applying RMST. CONCLUSIONS: We suggest that talazoparib in combination with enzalutamide is probably a preferred treatment agent for the overall population and HRRm patients with mCRPC. Given the limitations of network framework and the modeling assumptions undertaken to finalize the analyses, results should be cautiously interpreted.

Behavior of total alkaline phosphatase after radium-233 therapy in metastatic castration-resistant prostate cancer: a single-center, real-world retrospective study.

Objective: To describe the behavior of total alkaline phosphatase (tALP) in patients with metastatic castration-resistant prostate cancer receiving radium-223 therapy, in a real-world scenario, and to describe overall survival (OS) among such patients. Materials and Methods: This was a retrospective study involving 97 patients treated between February 2017 and September 2020. Patients were stratified by the baseline tALP (normal/elevated). A tALP response was defined as a ≥ 30% reduction from baseline at week 12. For patients with elevated baseline tALP, we also evaluated treatment response as a ≥ 10% reduction in tALP after the first cycle of treatment. We defined OS as the time from the first treatment cycle to the date of death. Results: There was a significant reduction in the median tALP after each cycle of treatment (p < 0.05 for all). Data for tALP at week 12 were available for 71 of the 97 patients. Of those 71 patients, 26 (36.6%) responded. Elevated baseline tALP was observed in 47 patients, of whom 19 (40.4%) showed a response. Longer OS was observed in the patients with normal baseline tALP, in those with elevated baseline tALP that showed a response to treatment (≥ 10% reduction), and in those who received 5-6 cycles of therapy. Conclusion: The tALP may be used to predict which patients will benefit from treatment with a greater number of cycles of radium-223 therapy and will have longer OS.

Objetivo: Descrever o comportamento da fosfatase alcalina total (tALP) em pacientes com carcinoma de próstata metastático resistente a castração, submetidos a terapia com rádio-223 em um cenário do mundo real, e a sobrevida global (SG) desses pacientes. Materiais e Métodos: Estudo retrospectivo envolvento 97 pacientes, no período de fevereiro/2017 a setembro/2020. Os pacientes foram estratificados de acordo com a tALP basal (normal/elevada). A resposta à tALP foi definida como uma redução em relação à linha de base de ≥ 30% na semana-12. Para pacientes com tALP basal elevada, também foi avaliada a resposta ao tratamento como uma redução de ≥ 10% de tALP após o primeiro ciclo. A SG foi definida como o tempo entre o primeiro ciclo e a data do óbito. Resultados: A redução da tALP média após cada ciclo foi significativa (p < 0,05). A tALP na semana 12 estava disponível para 71 dos 97 pacientes. Desses 71 pacientes, 26 (36,6%) responderam. Dezenove (40,4%) dos 47 pacientes com tALP elevada apresentaram resposta. Foi observada uma SG mais longa nos pacientes com tALP basal normal, nos pacientes com tALP basal elevada que apresentaram resposta ao tratamento (redução de ≥ 10%) e nos pacientes que receberam 5-6 ciclos. Conclusão: A tALP pode ser usada para prever parte dos pacientes que se beneficiarão do tratamento com um maior número de ciclos e uma SG mais longa.

Behavior of total alkaline phosphatase after radium-233 therapy in metastatic castration-resistant prostate cancer: a single-center, real-world retrospective study / Estudo retrospectivo de vida-real, em centro único, para avaliação do comportamento da fosfatase alcalina total após terapia com rádio-223 no câncer de próstata resistente a castração

Abstract Objective: To describe the behavior of total alkaline phosphatase (tALP) in patients with metastatic castration-resistant prostate cancer receiving radium-223 therapy, in a real-world scenario, and to describe overall survival (OS) among such patients. Materials and Methods: This was a retrospective study involving 97 patients treated between February 2017 and September 2020. Patients were stratified by the baseline tALP (normal/elevated). A tALP response was defined as a ≥ 30% reduction from baseline at week 12. For patients with elevated baseline tALP, we also evaluated treatment response as a ≥ 10% reduction in tALP after the first cycle of treatment. We defined OS as the time from the first treatment cycle to the date of death. Results: There was a significant reduction in the median tALP after each cycle of treatment (p < 0.05 for all). Data for tALP at week 12 were available for 71 of the 97 patients. Of those 71 patients, 26 (36.6%) responded. Elevated baseline tALP was observed in 47 patients, of whom 19 (40.4%) showed a response. Longer OS was observed in the patients with normal baseline tALP, in those with elevated baseline tALP that showed a response to treatment (≥ 10% reduction), and in those who received 5-6 cycles of therapy. Conclusion: The tALP may be used to predict which patients will benefit from treatment with a greater number of cycles of radium-223 therapy and will have longer OS.

Resumo Objetivo: Descrever o comportamento da fosfatase alcalina total (tALP) em pacientes com carcinoma de próstata metastático resistente a castração, submetidos a terapia com rádio-223 em um cenário do mundo real, e a sobrevida global (SG) desses pacientes. Materiais e Métodos: Estudo retrospectivo envolvento 97 pacientes, no período de fevereiro/2017 a setembro/2020. Os pacientes foram estratificados de acordo com a tALP basal (normal/elevada). A resposta à tALP foi definida como uma redução em relação à linha de base de ≥ 30% na semana-12. Para pacientes com tALP basal elevada, também foi avaliada a resposta ao tratamento como uma redução de ≥ 10% de tALP após o primeiro ciclo. A SG foi definida como o tempo entre o primeiro ciclo e a data do óbito. Resultados: A redução da tALP média após cada ciclo foi significativa (p < 0,05). A tALP na semana 12 estava disponível para 71 dos 97 pacientes. Desses 71 pacientes, 26 (36,6%) responderam. Dezenove (40,4%) dos 47 pacientes com tALP elevada apresentaram resposta. Foi observada uma SG mais longa nos pacientes com tALP basal normal, nos pacientes com tALP basal elevada que apresentaram resposta ao tratamento (redução de ≥ 10%) e nos pacientes que receberam 5-6 ciclos. Conclusão: A tALP pode ser usada para prever parte dos pacientes que se beneficiarão do tratamento com um maior número de ciclos e uma SG mais longa.

LOX-1 Activation by oxLDL Induces AR and AR-V7 Expression via NF-κB and STAT3 Signaling Pathways Reducing Enzalutamide Cytotoxic Effects.

The oxidized low-density lipoprotein receptor 1 (LOX-1) is one of the most important receptors for modified LDLs, such as oxidated (oxLDL) and acetylated (acLDL) low-density lipoprotein. LOX-1 and oxLDL are fundamental in atherosclerosis, where oxLDL/LOX1 promotes ROS generation and NF-κB activation inducing the expression of IL-6, a STAT3 activator. Furthermore, LOX-1/oxLDL function has been associated with other diseases, such as obesity, hypertension, and cancer. In prostate cancer (CaP), LOX-1 overexpression is associated with advanced stages, and its activation by oxLDL induces an epithelial-mesenchymal transition, increasing angiogenesis and proliferation. Interestingly, enzalutamide-resistant CaP cells increase the uptake of acLDL. Enzalutamide is an androgen receptor (AR) antagonist for castration-resistant prostate cancer (CRPC) treatment, and a high percentage of patients develop a resistance to this drug. The decreased cytotoxicity is promoted in part by STAT3 and NF-κB activation that induces the secretion of the pro-inflammatory program and the expression of AR and its splicing variant AR-V7. Here, we demonstrate for the first time that oxLDL/LOX-1 increases ROS levels and activates NF-κB, inducing IL-6 secretion and the activation of STAT3 in CRPC cells. Furthermore, oxLDL/LOX1 increases AR and AR-V7 expression and decreases enzalutamide cytotoxicity in CRPC. Thus, our investigation suggests that new factors associated with cardiovascular pathologies, such as LOX-1/oxLDL, may also promote important signaling axes for the progression of CRPC and its resistance to drugs used for its treatment.

DDX5 mRNA-targeting antisense oligonucleotide as a new promising therapeutic in combating castration-resistant prostate cancer.

The heat shock protein 27 (Hsp27) has emerged as a principal factor of the castration-resistant prostate cancer (CRPC) progression. Also, an antisense oligonucleotide (ASO) against Hsp27 (OGX-427 or apatorsen) has been assessed in different clinical trials. Here, we illustrate that Hsp27 highly regulates the expression of the human DEAD-box protein 5 (DDX5), and we define DDX5 as a novel therapeutic target for CRPC treatment. DDX5 overexpression is strongly correlated with aggressive tumor features, notably with CRPC. DDX5 downregulation using a specific ASO-based inhibitor that acts on DDX5 mRNAs inhibits cell proliferation in preclinical models, and it particularly restores the treatment sensitivity of CRPC. Interestingly, through the identification and analysis of DDX5 protein interaction networks, we have identified some specific functions of DDX5 in CRPC that could contribute actively to tumor progression and therapeutic resistance. We first present the interactions of DDX5 and the Ku70/80 heterodimer and the transcription factor IIH, thereby uncovering DDX5 roles in different DNA repair pathways. Collectively, our study highlights critical functions of DDX5 contributing to CRPC progression and provides preclinical proof of concept that a combination of ASO-directed DDX5 inhibition with a DNA damage-inducing therapy can serve as a highly potential novel strategy to treat CRPC.

"Non-metastatic, Castration-resistant Prostate Cancer: Diagnostic and Treatment Recommendations by an Expert Panel from Brazil".

INTRODUCTION: Non-metastatic, castration-resistant prostate cancer (nmCRPC) is an important clinical stage of prostate cancer, prior to morbidity and mortality from clinical metastases. In particular, the introduction of novel androgen-receptor signaling inhibitors (ARSi) has changed the therapeutic landscape in nmCRPC. Given recent developments in this field, we update our recommendations for the management of nmCRPC. METHODS: A panel of 51 invited medical oncologists and urologists convened in May of 2021 with the aim of discussing and providing recommendations regarding the most relevant issues concerning staging methods, antineoplastic therapy, osteoclast-targeted therapy, and patient follow-up in nmCRPC. Panel members considered the available evidence and their practical experience to address the 73 multiple-choice questions presented. RESULTS: Key recommendations and findings include the reliance on prostate-specific antigen doubling time for treatment decisions, the absence of a clear preference between conventional and novel (i.e., positron-emission tomography-based) imaging techniques, the increasing role of ARSis in various settings, the general view that ARSis have similar efficacy. Panelists highlighted the slight preference for darolutamide, when safety is of greater concern, and a continued need to develop high-level evidence to guide the intensity of follow-up in this subset of prostate cancer. DISCUSSION: Despite the limitations associated with a consensus panel, the topics addressed are relevant in current practice, and the recommendations can help practicing clinicians to provide state-of-the-art treatment to patients with nmCRPC in Brazil and other countries with similar healthcare settings.

Application of the ASCO value framework to evaluate the clinical and economic value of enzalutamide and apalutamide in the early stages of prostate cancer in Colombia.

Introduction: Prostate cancer has increased in recent years, increasing the costs associated with its treatment. Second-generation oral antiandrogens have emerged as an attractive therapeutic option. Objective: To compare the health value provided by enzalutamide and apalutamide, by evaluating two stages of prostate cancer: non-metastatic castration-resistant prostate cancer (nmCRPC) and metastatic hormone-sensitive prostate cancer (mHSPC). Methods: To establish, through the American Society of Clinical Oncology (ASCO) value framework, a contrast between two technologies in two stages of prostate cancer. The monthly cost of the two technologies was calculated according to the current price regulation norm in Colombia. Results: Enzalutamide showed a higher net health benefit score compared to apalutamide for both nmCRPC (48.33 versus 33.46) and mHSPC (52.0 versus 40.75). The cost per net health benefit point for the nmCRPC stage was $214,723 Colombian Pesos (COP) ($54.84 USD) with enzalutamide compared to $291,925 COP ($74.56 USD) with apalutamide, and for the mHSPC stage was $199,692 COP ($51.00 USD) with enzalutamide and $239,701 COP ($61.22 USD) with apalutamide. Conclusion: After comparing enzalutamide versus apalutamide in the nmCRPC and mHSPC stages through the ASCO value framework, enzalutamide showed a more prominent net clinical benefit and a lower investment per point awarded.

Salvage Radical Prostatectomy in Nonmetastatic Castration-Resistant Prostate Cancer.

OBJECTIVE: To analyze the perioperatory and short-oncological outcomes in 5 cases with CRPC M0 developed after pRT that underwent salvage laparoscopic RP (sLRP) and review the current evidence. MATERIAL AND METHODS: Perioperatory and oncological outcomes were prospectively analyzed. Inclusion criteria were patients that had received pRT and posteriorly presented with CRPC M0 in standard imagines and positron emission tomography MRI coline. Evidence was reviewed in PUBMED database. RESULTS: No surgical complications and blood transfusion were reported. Two patients required an endoscopic urethrotomy due to bladder neck contracture (Clavien IIIb). Final pathological findings were T3 or more, multifocal with 3 positive surgical margins. Four patients reach undetectable PSA after surgery except one that continuous under ADT without disease progression. After 12 months follow-up, 4 patients persist with undetectable PSA and one with stable disease under ADT. Current evidence demonstrated that CRPC M0 treated with open, laparoscopic or robotic RP a biochemical recurrence of 68.7% as a hormone-sensitive PC; however, 17.4% were disease-free after 4 years of follow-up. CONCLUSION: Our serie, 4 cases are disease free after 12 months follow-up. Current evidence is a retrospective and multicenter experience with few cases and intermediate oncological follow-up. More cases with longer follow-up and better evidence are required to opt for this treatment as a first line.

Identificación de variantes del gen BRCA 1 Y BRCA 2 en pacientes con cáncer de próstata resistente a la castración del Hospital Central Militar / Identification of BRCA 1 AND BRCA 2 gene variants in patients with castration-resistant prostate cancer at the Hospital Central Militar

Resumen El cáncer de próstata metastásico resistente a la castración (CPRC) es una neoplasia heterogénea letal entre los hombres. 30% de los tumores acumulan errores deletéreos en genes implicados en la respuesta al daño del ADN (DNA damage response en inglés, DDR). Algunos de estos genes asociados a cáncer son BRCA 1 y BRCA 2. Mutaciones en estos genes favorecen la pérdida o la modificación de la función provocando un cambio permanente y transmisible, lo que conduce al desarrollo de cáncer de próstata agresivo. El objetivo del estudio fue identificar mediante secuenciación dirigida (Next-generation sequencing; NGS) variantes génicas de BRCA 1 y BRCA 2 en el genoma de pacientes con CPRC del Hospital Central Militar. Es importante destacar que los resultados demostraron una serie de alteraciones clínicas, así como una pérdida de la función de las proteínas relacionadas con mecanismos de reparación del ADN. Curiosamente, algunas de las variantes en el gen BRCA, de las que se informa aquí, son de significado incierto, lo que nos ha sido comunicado por primera vez.

Abstract Metastatic castration-resistant prostate cancer (CRPC) is a heterogeneous lethal neoplasm among men. 30% of tumors harbor deleterious errors in genes involved in the DNA damage response (DDR). Some of these cancer-associated genes are BRCA 1 and BRCA 2. Mutations to these genes favor loss or modification of function causing a permanent and transmissible change, leading to the development of aggressive prostate cancer. The aim of the study was to identify by Next-generation sequencing (NGS) BRCA 1 and BRCA 2 gene variants in peripheral blood of patients with CRPC at the Hospital Central Militar. Importantly, the results demonstrated a number of clinical alterations, as well as a loss of function of proteins related to DNA repair mechanisms. Interestingly, some of the variants in the BRCA gene, reported here, are of uncertain significance, which has been reported to us for the first time.

Evaluation of maintenance of the common androgen deprivation therapy with the new antiandrogen therapy in patients with castration-resistant prostate cancer: a systematic review.

PURPOSE: Advanced prostate cancer does not respond to traditional androgen deprivation therapy (ADT) at some point in the treatment. The development of new hormonal agents demonstrated clear efficacy and changed the treatment scenario. OBJECTIVES: To evaluate the use of new antiandrogens alone versus their use in combination with maintenance ADT in patients with advanced castration-resistant prostate cancer. METHODS: A literature systematic review of randomized clinical trials, cohorts, and real-life studies including patients who received the new antiandrogens with or without ADT due to histologic confirmed advanced castration-resistant prostate adenocarcinoma was carried out. RESULTS: 2181 articles were identified and three studies were included with a total of 246 patients. Two studies were randomized clinical trials, and the third was a retrospective study, which showed similar results for both arms, in relation to PSA response, radiological progression-free survival, and testosterone levels, in addition to cost analysis with savings avoided in the ADT maintenance-free arm. Despite the positive data, it is still not possible to categorically state whether there is a statistical benefit in suspending the ADT during the use of new antiandrogens, due to the heterogeneity of the studies. CONCLUSION: The literature is limited on the issue. Available data are still immature with no clear benefit of the use of newer antiandrogens alone in the setting of advanced castration-resistant prostate cancer.

Treatment Patterns Among Patients With Advanced Prostate Cancer in Brazil: An Analysis of a Private Healthcare System Database.

Background: With the ongoing expansion of life-prolonging therapies approved to treat advanced prostate cancer, there is currently an unmet need to better understand real-world treatment patterns and identify optimal treatment sequencing for men with metastatic castration-resistant prostate cancer (mCRPC). Methods: In this retrospective, observational cohort analysis, patients with confirmed mCRPC were identified in the Auditron claims database and used to describe mCRPC treatment patterns and trends in the Brazilian private healthcare system from 2014 to 2019. Demographics and clinical characteristics, prostate cancer stage at diagnosis, and type and number of treatment lines were evaluated. The primary endpoint was identification of the drugs used in first-line therapies in mCRPC, and the secondary endpoint included a description of sequential lines of therapy (second and third lines) in mCRPC. Results: A total of 168 electronic patient records were reviewed. Docetaxel was the most frequently used first-line treatment (35.7%), followed by abiraterone (33.3%) and enzalutamide (13.1%). Docetaxel, abiraterone, and enzalutamide also accounted for 34.6%, 28.0%, and 15.0%, respectively, of second-line therapies. In third-line therapies, cabazitaxel (26.1%), enzalutamide (23.9%), docetaxel (15.2%), and abiraterone (15.2%) were most commonly prescribed. Irrespective of stage at diagnosis, treatment patterns were similar once the disease progressed to the metastatic castration-resistance stage. Conclusions: Docetaxel was the most frequently utilized therapy for mCRPC treatment, followed by abiraterone and enzalutamide. Although the current analyses provide real-world insights into treatment patterns for patients with mCRPC in Brazil, additional real-world data are needed to further validate and expand on these findings.

Influence of statins in metastatic castration-resistant prostate cancer patients treated with new antiandrogen therapies: a systematic review and meta-analysis

ABSTRACT Objective To evaluate whether the addition of statins to the new antiandrogens (enzalutamide or abiraterone) affects overall survival in patients with metastatic castration-resistant prostate cancer. Methods We searched studies in English language including the keywords statins, overall survival, and metastatic castration-resistant prostate cancer, at PubMed® (MEDLINE®), Embase and Cochrane databases. Results A total of 195 articles were initially identified, but only four met the inclusion criteria and were selected for the meta-analysis. A total of 955 patients, 632 on the new antiandrogens only group, and 323 on the new antiandrogens + statins group, were analyzed. In all four studies the combination therapy (new antiandrogens + statin) was well tolerated, regardless of which new antiandrogens were used. Neither the type of statin nor the doses and duration of use were well specified in the studies. The combination therapy in metastatic castration-resistant prostate cancer was associated with an overall survival improvement, and a 46% reduction in death (hazard ratio of 0.54; 95%CI 0.34-0.87; p<0.01) in multivariate analysis. Conclusion There seems to be a clinical benefit with the association of statins to the new antiandrogens in patients with metastatic castration-resistant prostate cancer, suggesting longer overall survival with no important collateral effect. However, due to fragility of the studies available in the literature, we are not yet capable of recommending this combination of drugs in the clinical practice. Further randomized prospective studies are warranted to confirm these beneficial outcomes.

Endothelin-1 induces changes in the expression levels of steroidogenic enzymes and increases androgen receptor and testosterone production in the PC3 prostate cancer cell line.

Endothelin­1 (ET­1) is involved in the regulation of steroidogenesis. Additionally, patients with castration­resistant prostate cancer (PCa) have a higher ET­1 plasma concentration than those with localized PCa and healthy individuals. The aim of the present study was to evaluate the effect of ET­1 on steroidogenesis enzymes, androgen receptor (AR) and testosterone (T) production in PCa cells. The expression levels of endothelin receptors in prostate tissue from patients with localized PCa by immunohistochemistry, and those in LNCaP and PC3 cells were determined reverse transcription­quantitative PCR (RT­qPCR) and western blotting. Furthermore, the expression levels of ET­1 were determined in LNCaP and PC3 cells by RT­qPCR and western blotting. The ET­1 receptor activation was evaluated by intracellular calcium measurement, the expression levels of AR and enzymes participating in steroidogenesis [cytochrome P450 family 11 subfamily A member 1 (CyP11A1), cytochrome P450 family 17 subfamily A member 1, aldo­keto reductase family member C2 and 3ß­hydroxysteroid dehydrogenase/isomerase 2 (3ß HSD2)] were determined by western blotting and T concentration was determined by ELISA using PC3 cells. The present results revealed higher expression levels of endothelin A receptor (ETAR) in tissues obtained from samples of patients with PCa with a low Gleason Score. No changes were identified for endothelin B receptor (ETBR). PC3 cells expressed higher levels of ET­1 and ETAR, while LNCaP cells exhibited higher expression levels of ETBR. Blocking of ETAR and endothelin B receptor decreased the expression levels of CyP11A1 and 3ß HSD2 enzymes and AR in PC3 cells, as well as T secretion. These findings suggested that ET­1 has a potential role in modulating the intratumoral steroidogenesis pathway and might have relevance as a possible therapeutic target.

68Ga-PSMA PET/CT: effect of external cooling on salivary gland uptake.

OBJECTIVE: To evaluate the effect that external cooling of the salivary glands (ECSG) has on the uptake of gallium-68-labeled prostate-specific membrane antigen (68Ga-PSMA), as an indirect assessment of the capacity of ECSG to reduce the local dose in lutetium-177-PSMA-617 radioligand therapy. MATERIALS AND METHODS: Ten patients with prostate cancer were submitted to 68Ga-PSMA positron emission tomography/computed tomography with unilateral ECSG. The ECSG was started at 30 min before the injection of the radiotracer and maintained until the end of image acquisition (1 h after injection). Each salivary gland was assessed by determining the maximum, mean, and peak standardized uptake values (SUVmax, SUVmean, and SUVpeak, respectively). The volume of each gland was determined in a volume of interest delineated by a threshold SUVmax of 10%. Paired Student's t-tests were used in order to compare the results. RESULTS: In terms of the SUV parameters, there were no statistically significant differences between the cooled and contralateral salivary glands. However, the mean volume was 27% lower in the cooled parotid glands than in the contralateral parotid glands (p = 0.004). CONCLUSION: The use of ECSG does not appear to reduce 68Ga-PSMA uptake by the salivary glands. In addition, there is yet no evidence that ECSG is effective in preventing salivary gland toxicity.

OBJETIVO: Avaliar o impacto do resfriamento externo de glândulas salivares (REGS) na captação de 68Ga-PSMA como marcador indireto dessa intervenção para redução da dose local na terapia com 177Lu-PSMA. MATERIAIS E MÉTODOS: Dez pacientes com câncer de próstata foram submetidos a PET/CT com 68Ga-PSMA com REGS unilateral. O resfriamento se iniciou 30 minutos antes da injeção do radiofármaco até o fim da aquisição de imagem, 1 hora após a injeção. Cada glândula foi avaliada para os valores de captação padronizados máximo, médio e pico (SUVmáx, SUVmédio e SUVpico, respectivamente). O volume foi definido por um isocontorno usando 10% do SUVmáx. Os resultados foram comparados com o teste t de Student. RESULTADOS: Não houve diferença estatisticamente significante entre os valores de SUV das glândulas resfriadas e seus controles. Houve 27% de redução volumétrica (p = 0,004) nas parótidas resfriadas em comparação ao controle. CONCLUSÃO: Não houve redução da captação de 68Ga-PSMA nas glândulas salivares ao REGS. Atualmente não há evidências que suportem essa prática clínica.

68Ga-PSMA PET/CT: effect of external cooling on salivary gland uptake / PET/CT com 68Ga-PSMA: efeitos do resfriamento externo na captação pelas glândulas salivares

Abstract Objective: To evaluate the effect that external cooling of the salivary glands (ECSG) has on the uptake of gallium-68-labeled prostate-specific membrane antigen (68Ga-PSMA), as an indirect assessment of the capacity of ECSG to reduce the local dose in lutetium-177-PSMA-617 radioligand therapy. Materials and Methods: Ten patients with prostate cancer were submitted to 68Ga-PSMA positron emission tomography/computed tomography with unilateral ECSG. The ECSG was started at 30 min before the injection of the radiotracer and maintained until the end of image acquisition (1 h after injection). Each salivary gland was assessed by determining the maximum, mean, and peak standardized uptake values (SUVmax, SUVmean, and SUVpeak, respectively). The volume of each gland was determined in a volume of interest delineated by a threshold SUVmax of 10%. Paired Student's t-tests were used in order to compare the results. Results: In terms of the SUV parameters, there were no statistically significant differences between the cooled and contralateral salivary glands. However, the mean volume was 27% lower in the cooled parotid glands than in the contralateral parotid glands (p = 0.004). Conclusion: The use of ECSG does not appear to reduce 68Ga-PSMA uptake by the salivary glands. In addition, there is yet no evidence that ECSG is effective in preventing salivary gland toxicity.

Resumo Objetivo: Avaliar o impacto do resfriamento externo de glândulas salivares (REGS) na captação de 68Ga-PSMA como marcador indireto dessa intervenção para redução da dose local na terapia com 177Lu-PSMA. Materiais e Métodos: Dez pacientes com câncer de próstata foram submetidos a PET/CT com 68Ga-PSMA com REGS unilateral. O resfriamento se iniciou 30 minutos antes da injeção do radiofármaco até o fim da aquisição de imagem, 1 hora após a injeção. Cada glândula foi avaliada para os valores de captação padronizados máximo, médio e pico (SUVmáx, SUVmédio e SUVpico, respectivamente). O volume foi definido por um isocontorno usando 10% do SUVmáx. Os resultados foram comparados com o teste t de Student. Resultados: Não houve diferença estatisticamente significante entre os valores de SUV das glândulas resfriadas e seus controles. Houve 27% de redução volumétrica (p = 0,004) nas parótidas resfriadas em comparação ao controle. Conclusão: Não houve redução da captação de 68Ga-PSMA nas glândulas salivares ao REGS. Atualmente não há evidências que suportem essa prática clínica.

Decoding the heterogeneous landscape in the development prostate cancer.

Prostate cancer (PCa) is characterized as being histologically and molecularly heterogeneous; however, this is not only incorrect among individuals, but also at the multiple foci level, which originates in the prostate gland itself. The reasons for such heterogeneity have not been fully elucidated; however, understanding these may be crucial in determining the course of the disease. PCa is characterized by a complex network of chromosomal rearrangements, which simultaneously deregulate multiple genes; this could explain the appearance of exclusive events associated with molecular subtypes, which have been extensively investigated to establish clinical management and the development of therapies targeted to this type of cancer. From a clinical aspect, the prognosis of the patient has focused on the characteristics of the index lesion (the largest focus in PCa); however, a significant percentage of patients (11%) also exhibit an aggressive secondary foci, which may determine the prognosis of the disease, and could be the determining factor of why, in different studies, the classification of the subtypes does not have an association with prognosis. Due to the aforementioned reasons, the analysis of molecular subtypes in several foci, from the same individual could assist in determining the association between clinical evolution and management of patients with PCa. Castration-resistant PCa (CRPC) has the worst prognosis and develops following androgen ablation therapy. Currently, there are two models to explain the development of CRPC: i) The selection model and ii) the adaptation model; both of which, have been found to include alterations described in the molecular subtypes, such as Enhancer of zeste 2 polycomb repressive complex 2 subunit overexpression, isocitrate dehydrogenase (NAPD+)1 and forkhead box A1 mutations, suggesting that the presence of specific molecular alterations could predict the development of CRPC. This type of analysis could lead to a biological understanding of PCa, to develop personalized medicine strategies, which could improve the response to treatment thus, avoiding the development of resistance. Therefore, the present review discusses the primary molecular factors, to which variable heterogeneity in PCa progress has been attributed.

Consensus on diagnosis and management of non-metastatic castration resistant prostate cancer in Brazil: focus on patient, selection, treatment efficacy, side effects and physician's perception according to patient comorbidities

ABSTRACT Background: Non-metastatic castration resistant prostate cancer (M0 CRPC) has seen important developments in drugs and diagnostic tools in the last two years. New hormonal agents have demonstrated improvement in metastasis free survival in M0 CRPC patients and have been approved by regulatory agencies in Brazil. Additionally, newer and more sensitive imaging tools are able to detect metastasis earlier than before, which will impact the percentage of patients staged as M0 CRPC. Based on the available international guidelines, a group of Brazilian urology and medical oncology experts developed and completed a survey on the diagnosis and treatment of M0 CRPC in Brazil. These results are reviewed and summarized and associated recommendations are provided. Objective: To present survey results on management of M0 CRPC in Brazil. Design, setting, and participants: A panel of six Brazilian prostate cancer experts determined 64 questions concerning the main areas of interest: 1) staging tools, 2) treatments, 3) side effects of systemic treatment/s, and 4) osteoclast-targeted therapy. A larger panel of 28 Brazilian prostate cancer experts answered these questions in order to create country-specific recommendations discussed in this manuscript. Outcome measurements and statistical analysis: The panel voted publicly but anonymously on the predefined questions. These answers are the panelists' opinions, not a literature review or meta-analysis. Therapies not yet approved in Brazil were excluded from answer options. Each question had five to seven relevant answers including two non-answers. Results were tabulated in real time. Conclusions: The results and recommendations presented can be used by Brazilian physicians to support the management of M0 CRPC patients. Individual clinical decision making should be supported by available data, however, for Brazil, guidelines for diagnosis and management of M0 CRPC patients have not been developed. This document will serve as a point of reference when confronting this disease stage.