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.

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.

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.

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.

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.

Stereotactic ablative radiotherapy in castration-resistant prostate cancer patients with oligoprogression during androgen receptor-targeted therapy.

OBJECTIVES: To report outcomes of stereotactic body radiotherapy (SBRT) in metastatic castration-resistant prostate cancer (mCRPC) patients with oligoprogression (≤ 5 metastases) during first-line treatment with androgen receptor-targeted therapy (ARTT). PATIENTS AND METHODS: Retrospective multi-institutional analysis of mCRPC patients treated with SBRT to oligoprogressive lesions during ARTT. End-points were time to next-line systemic treatment (NEST), radiological progression-free survival (r-PFS) and overall survival (OS). Toxicity was registered according to Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Survival analysis was performed using the Kaplan-Meier method, univariate and multivariate analysis (MVA) were performed. RESULTS: Data from 34 patients were analyzed. Median NEST-free survival, r-PFS, and OS were 16.97, 13.47, and 38.3 months, respectively. At MVA, factors associated with worse NEST-free survival and r-PFS were polymetastatic burden at diagnosis of metastatic hormone-sensitive disease (hazard ratio [HR] 3.66, p = 0.009; HR 3.03, p = 0.034), PSA ≤ 7 ng/ml at mCRPC diagnosis (HR 0.23, p = 0.017; HR 0.19, p = 0.006) and PSADT ≤ 3 months at mCRPC diagnosis (HR 3.39, p = 0.026; HR 2.79, p = 0.037). Polymetastatic state at mHSPC diagnosis was associated with a decreased OS (HR 4.68, p = 0.029). No patient developed acute or late grade ≥ 2 toxicity. CONCLUSION: Our results suggest that SBRT in oligoprogressive mCPRC is safe, effective and seems to prolong the efficacy of the ongoing systemic treatment positively affecting disease progression. Prospective trials are needed.

New inhibitor targeting Acyl-CoA synthetase 4 reduces breast and prostate tumor growth, therapeutic resistance and steroidogenesis.

Acyl-CoA synthetase 4 (ACSL4) is an isoenzyme of the fatty acid ligase-coenzyme-A family taking part in arachidonic acid metabolism and steroidogenesis. ACSL4 is involved in the development of tumor aggressiveness in breast and prostate tumors through the regulation of various signal transduction pathways. Here, a bioinformatics analysis shows that the ACSL4 gene expression and proteomic signatures obtained using a cell model was also observed in tumor samples from breast and cancer patients. A well-validated ACSL4 inhibitor, however, has not been reported hindering the full exploration of this promising target and its therapeutic application on cancer and steroidogenesis inhibition. In this study, ACSL4 inhibitor PRGL493 was identified using a homology model for ACSL4 and docking based virtual screening. PRGL493 was then chemically characterized through nuclear magnetic resonance and mass spectroscopy. The inhibitory activity was demonstrated through the inhibition of arachidonic acid transformation into arachidonoyl-CoA using the recombinant enzyme and cellular models. The compound blocked cell proliferation and tumor growth in both breast and prostate cellular and animal models and sensitized tumor cells to chemotherapeutic and hormonal treatment. Moreover, PGRL493 inhibited de novo steroid synthesis in testis and adrenal cells, in a mouse model and in prostate tumor cells. This work provides proof of concept for the potential application of PGRL493 in clinical practice. Also, these findings may prove key to therapies aiming at the control of tumor growth and drug resistance in tumors which express ACSL4 and depend on steroid synthesis.

Combination of statin/vitamin D and metastatic castration-resistant prostate cancer (CRPC): a post hoc analysis of two randomized clinical trials.

In castration-resistant prostate cancer (CRPC) patients, observational studies have reported that statins may boost the antitumor activity of abiraterone (AA) and data suggest an improvement in efficacy; conclusions with vitamin D are less clear but an eventual benefit has been pointed. We conducted a post hoc analysis of individual patient data of CRPC patients treated with prednisone and/or AA with or without statins/vitamin D on randomized clinical trials. In the COU-AA-301 trial, use of AA with statin and vitamin D reduced the risk of death by 38% (p = 0.0007) while AA alone was associated with a decrease of 10% (p = 0.025), compared to prednisone alone. Meanwhile, in the COU-AA-302 trial, use of AA plus statin plus vitamin D was associated with a reduced risk of death of 26% (p = 0.0054). In this data analysis from two prospective randomized clinical trials, statin and vitamin D use was associated with superior overall survival in metastatic CRPC patients treated with AA and prednisone. To our knowledge, this is the first report suggesting the impact of statin plus vitamin D in this population. New strategies using big data may help to clarify these questions easily and in a most cost-effective approach.

Consensus on management of castration-resistant prostate cancer on behalf of the Urological Tumours Working Group (URONCOR) of the Spanish Society of Radiation Oncology.

BACKGROUND: The knowledge in the field of castration-resistant prostate cancer (CRPC) is developing rapidly, with emerging new therapies and advances in imaging. Nonetheless, in multiple areas there is still a lack of or very limited evidence, and clear guidance from clinicians regarding optimal strategy is required. METHODS: A modified Delphi method, with 116 relevant questions divided into 7 different CRPC management topics, was used to develop a consensus statement by the URONCOR group. RESULTS: A strong consensus or unanimity was reached on 93% of the proposed questions. The seven topics addressed were: CRPC definition, symptomatic patients, diagnosis of metastasis, CRPC progression, M0 management, M1 management and sequencing therapy, and treatment monitoring. CONCLUSIONS: The recommendations based on the radiation oncology experts' opinions are intended to provide cancer specialists with expert guidance and to standardise CRPC patient management in Spain, facilitating decision-making in different clinically relevant issues regarding CRPC patients.

MicroRNA-23b and microRNA-27b plus flutamide treatment enhances apoptosis rate and decreases CCNG1 expression in a castration-resistant prostate cancer cell line.

The acquisition of a castration-resistant prostate cancer phenotype by prostate cancer cells is the alteration that has the worst prognosis for patients. The aim of this study was to evaluate the role of the microRNAs-23b/-27b as well as the possible CCNG1 target gene in tissue samples from patients with localized prostate cancer that progressed to castration-resistant prostate cancer and in a castration-resistant prostate cancer cell line (PC-3). The microRNAs and target gene expression levels of the surgical specimens were analyzed by quantitative real-time polymerase chain reaction. The prostate cancer cell line, PC-3, was transfected with pre-miR-23b, pre-miR-27b, and their respective controls using Lipofectamine RNAiMAX and exposed or not to flutamide. After transfections, expression levels of both the microRNAs and the gene, CCNG1, were analyzed by quantitative real-time polymerase chain reaction. The apoptosis and cell cycle assays were performed on the mini MUSE cytometer. MicroRNAs-23b/-27b were underexpressed in surgical specimens of prostate cancer; however, their target gene, CCNG1, was overexpressed in 69% of the cases. After transfection with the microRNAs-23b/-27b and flutamide, we observed a reduction in gene expression compared with cells that were treated only with microRNAs or only with flutamide. In the apoptosis assay, we demonstrated cell sensitization following transfection with microRNAs-23b/-27b and potentiation when co-administered with flutamide. The number of cells in apoptosis was almost three times higher with the simultaneous treatments (miR + flutamide) compared with the control (p < 0.05). In the cell cycle assay, only flutamide treatment showed better results; a higher number of cells were found in the G0-G1 phase, and a lower percentage of cells completed the final phase of the cycle (p < 0.05). We conclude that microRNAs-23b/-27b are downexpressed in prostate cancer, and their target gene, CCNG1, is overexpressed. We postulated that microRNAs-23b/-27b sensitize the PC-3 cell line and that after the addition of flutamide in the apoptosis assay, we would observe synergism in the treatments between miR and flutamide. In the cell cycle assay, the use of flutamide was sufficient to decrease the number of cells in mitosis. Therefore, we postulate that microRNAs, along with other drugs, may become very useful therapeutic tools in the treatment of castration-resistant prostate cancer.

CTC-derived AR-V7 detection as a prognostic and predictive biomarker in advanced prostate cancer.

INTRODUCTION: Prostate cancer is a highly heterogeneous disease, with remarkably different prognosis across all stages. Increased circulating tumor cell (CTC) count (≥ 5) using the CellSearch assay has been identified as one of the markers that can be used to predict survival, with added value beyond currently available prognostic factors. Recently, androgen receptor splice variant 7 (AR-V7) detection has been associated with worse outcomes for patients with castration-resistant prostate cancer (CRPC) treated with novel androgen receptor-signaling (ARS) inhibitors such as abiraterone and enzalutamide but not taxane chemotherapies. Areas covered: In this manuscript, the authors review the available biomarkers in CRPC and discuss emerging data on the value of CTC-derived AR-V7 status to assess prognosis and its potential role to guide treatment selection for patients with advanced prostate cancer. Expert commentary: Current evidence supports AR-V7 status as a prognostic biomarker and also as a potential predictive biomarker for patients with mCRPC. The authors expect that the incorporation of AR-V7 status and other biomarkers (e.g. AR mutations) in the sequential assessment of patients with advanced prostate cancer will lead to a more rational use of available and future therapies, with significant improvements in outcomes for our patients.

SEOM clinical guidelines for the treatment of metastatic prostate cancer (2017).

Androgen deprivation treatment was the only treatment available for metastatic prostate cancer until recently, with docetaxel as the only treatment with a proven survival benefit in castration-resistant prostate cancer (CRPC). Several drugs have been approved in the castration-resistant disease (sipuleucel-T, cabazitaxel, abiraterone, enzalutamide, radium-223). More recently, docetaxel and abiraterone have been moved to the hormone-sensitive disease setting, achieving better patient survival. The purpose of this article is to define the state of the art in the treatment of prostate carcinoma.

Supervivencia del cáncer de próstata resistente a la castración en la práctica clínica y el papel del tratamiento / Survival of Castration-Resistant Prostate Cancer in Clinical Practice and the Role of Treatment

Resumen Objetivo: Evaluar en un contexto de práctica clínica la ventaja de supervivencia para pacientes con cáncer de próstata resistente a castración (CPRC) tratado activamente con diversos tratamientos que incluyen acetato de abiraterona (AA) y prednisona con o sin docetaxel. Material y método: Se analiza la supervivencia de pacientes con CPRC y se compara un grupo tratado con AA y prednisona (n = 33) con un control histórico formado por pacientes consecutivos tratados una década antes en la misma institución exclusivamente con retirada de antiandrógeno y medidas paliativas (n = 31). Se analizan variables clínico-patológicas predictivas de pronóstico en la población activamente tratada. Se evalúa la respuesta global a AA y el intervalo libre de progresión radiológica. Resultados: La supervivencia cáncer específica a 2 años fue 79% para pacientes tratados activamente y 17,2% para control (log-rank, p < 0,0001). Cinco de 13 pacientes con AA post-docetaxel (38,5%) recibieron después de AA quimioterapia de segunda línea (4 cabazitaxel y 1 vinorelbina) y 1 (7,7%) hormonoterapia con enzalutamida. Tres de 20 pacientes tratados con AA sin quimioterapia (15%) recibieron enzalutamida y solo 1 (5%) fue tratado con docetaxel. Los pacientes de menor edad (<65años; p = 0,02) y sin metástasis al diagnóstico (p = 0,04) tuvieron mejor pronóstico. Aquellos de PSA más alto (>45ng/ml; p = 0,09) y patrón de Gleason 5 en la biopsia se comportaron de manera más desfavorable. Globalmente el 75,8% tuvieron respuesta a AA (80% pre- y 69,2% post-quimioterapia; p = 0,1) y el 52,4% estuvieron libre de progresión radiológica al año (47,9% pre y 49,8% post-quimioterapia; log-rank, p = 0,3). Conclusión: El tratamiento de pacientes con CPRC prolonga la expectativa de supervivencia en un entorno de práctica clínica y es posible identificar factores predictivos de pronóstico en estos pacientes.

Abstract Purpose: To assess, in a clinical practice context, the survival advantages of patients with castration-resistant prostate cancer (CRPC) actively treated with several treatments that include abiraterone acetate (AA) and prednisone, with or without docetaxel. Material and Methods: An analysis was performed on patient survival with CRPC, and was compared to a group treated with AA and prednisone (n = 33), with a historical control treated exclusively with anti-androgen withdrawal and palliative measures (n = 31). In the population actively treated, variables predictive of prognosis were analysed, as well as an evaluation of the overall response to AA and radiographic progression-free survival. Results: Cancer-specific survival at 2 years was 79% for patients actively treated and 17.2% for control group (P<.0001). Five (38.5%) of 13 patients treated with AA post-docetaxel received second-line chemotherapy after AA (4 cabazitaxel, 1 vinorelbine), and one (7.7%) enzalutamide. Three (15%) of 20 patients treated with AA without chemotherapy received enzalutamide and 1(5%) docetaxel. The younger patients (<65yrs; P=.02) without metastases at diagnosis (P=.04) had better prognoses. Patients with higher PSA levels (>45 ng/ml; P=.09) and a Gleason pattern 5 in the biopsy had less favourable outcomes. There was a 75.8% over response to AA (80% preand 69.2%post-chemotherapy; P=.1), and 69.2%post-chemotherapy; P=.1), and 52.4% were radiographic progression-free at 1 year of treatment (47.9% pre- and 49.8% post-chemotherapy; P=.3). Conclusion: Treatment of CRPC patients extends survival expectations in a clinical practice setting and prognostic predictors can be identified in these patients.

Galeterone for the treatment of advanced prostate cancer: the evidence to date.

Major advances have been achieved recently in the treatment of metastatic castration-resistant prostate cancer, resulting in significant improvements in quality of life and survival with the use of several new agents, including the next-generation androgen receptor (AR)-targeted drugs abiraterone and enzalutamide. However, virtually all patients will eventually progress on these therapies and most will ultimately die of treatment-refractory metastatic disease. Recently, several mechanisms of resistance to AR-directed therapies have been uncovered, including the AR splice variant 7 (AR-V7), which is a ligand-independent constitutionally-active form of the AR that has been associated with poor outcomes to abiraterone and enzalutamide. Galeterone, a potent anti-androgen with three modes of action (CYP17 lyase inhibition, AR antagonism, and AR degradation), is a novel agent under clinical development that could potentially target both full-length AR and aberrant AR, including AR-V7. In this manuscript, we will first discuss the biological mechanisms of action of galeterone and then review the safety and efficacy data from Phase I and II clinical studies of galeterone in patients with metastatic castration-resistant prostate cancer. A Phase III study of galeterone (compared against enzalutamide) in AR-V7-positive patients is currently underway, and represents the first pivotal trial using a biomarker-selection design in this disease.