Considerations for the use of gonadotropin-releasing hormone agonists and antagonists in patients with prostate cancer

The Impact of Triptorelin on Hormone Levels in Human and Its Metabolite Confirmation Using Liquid Chromatography-Ion Trap/Time-of-Flight Mass Spectrometry (LC/MS-IT-TOF) and Liquid Chromatography-Orbitrap (LC-Orbitrap) for Doping Control Analysis

Triptorelin, a synthetic gonadotrophin-releasing hormone (GnRH), is mainly used in the clinical treatment of prostate cancer. The mechanism initially stimulates luteinizing hormone (LH) and testosterone secretion followed by suppression, resulting in a reduction in cancer progression. However, GnRHs are prohibited in doping control because of the indirect surge of LH and testosterone. Therefore, GnRH analog detection and confirmation are enforced by World Anti-Doping Agency (WADA) requirements. The effects of triptorelin on LH and endogenous steroid levels in urine and serum of five prostate cancer patients taking triptorelin for the first time were investigated and compared with leuprorelin. The samples were collected at 0.0 h, 3.0 h, 6.0 h, 1 month, and 3 months later after drug administration. The effect of triptorelin on LH levels was measured using a sandwich enzyme-linked immunoassay (ELISA). Testosterone and endogenous steroid levels were monitored using gas chromatography coupled with mass spectrometry (GC/MS). Triptorelin showed an advantage over leuprorelin on LH and testosterone suppression, which is preferable to use for prostate cancer treatment. In this study, triptorelin (5-10), a unique in vivo metabolite, was found in urine and serum and verified with synthetic triptorelin (5-10). The metabolite was analyzed using liquid chromatography combined with Orbitrap (LC-Orbitrap) and liquid chromatography coupled with ion trap/time-of-flight mass spectrometry (LC/MS-IT-TOF). When triptorelin levels are undetectable, the presence of triptorelin (5-10) in human urine can be used as evidence that triptorelin is being misused in doping control.

Targeting protein-protein interactions in drug discovery: Modulators approved or in clinical trials for cancer treatment

Protein-protein interactions (PPIs) form complex cellular networks fundamental to many key biological processes, including signal transduction, cell proliferation and DNA repair. In consequence, their perturbation is often associated with many human diseases. Targeting PPIs offers a promising approach in drug discovery and ongoing advancements in this field hold the potential to provide highly specific therapies for a wide range of complex diseases. Despite the development of PPI modulators is challenging, advances in the genetic, proteomic and computational level have facilitated their discovery and optimization. Focusing on anticancer drugs, in the last years several PPI modulators have entered clinical trials and venetoclax, which targets Bcl-2 family proteins, has been approved for treating different types of leukemia. This review discusses the clinical development status of drugs modulating several PPIs, such as MDM2-4/p53, Hsp90/Hsp90, Hsp90/CDC37, c-Myc/Max, KRAS/SOS1, CCR5/CCL5, CCR2/CCL2 or Smac/XIAP, in cancer drug discovery.

Cribriform Pattern Is a Predictive Factor of PSA Recurrence in Patients Receiving Radiotherapy After Prostatectomy

Background/Aim

In prostate cancer, robotic total prostatectomy is a popular treatment modality. However, prostate-specific antigen (PSA) recurrence after prostate cancer surgery remains a concern. Salvage radiotherapy is commonly used to treat PSA recurrence, but the recurrence rate after salvage radiotherapy is high, highlighting the need for better predictive markers. This study aimed to retrospectively evaluate the association between cribriform pattern and PSA recurrence in patients receiving radiotherapy after radical prostatectomy.

Patients and Methods

Data of 50 patients who underwent radiotherapy after total prostatectomy between January 2010 and May 2020 were retrospectively evaluated. The median age was 67 years. Among these patients, two cases involved postoperative irradiation, while 48 cases involved salvage irradiation after postoperative PSA recurrence. The median time from surgery to PSA recurrence was 38.3 months. The median radiation dose was 64 Gy in 32 fractions. Three-dimensional conformal radiation therapy was administered in 38 cases and intensity-modulated radiation therapy was used in 12 cases. Combined hormone therapy was administered in 21 cases. PSA levels were measured every 3 months after treatment. Statistical analysis between groups was performed by a t-test.

Results

The median follow-up period after radiotherapy was 31 months. No local recurrences were observed at the prostate bed, and no deaths related to prostate cancer were recorded during follow-up. However, 18 patients (36.0%) had PSA recurrence. The PSA recurrence rate based on the cribriform pattern was 17.6% in the none to moderate group (34 patients) and 75.0% in the severe cribriform pattern group (16 patients). The PSA recurrence rate was significantly higher in patients with a severe invasive cribriform pattern (p=0.001). No significant differences were observed in other histopathological characteristics.

Conclusion

The cribriform pattern in surgical pathology specimens was found to be a useful predictor of PSA recurrence after postoperative radiotherapy.

Nomogram Analysis for Predicting Response to Androgen-Receptor-Axis-Targeted Therapies in Patients With Metastatic Castration-Resistant Prostate Cancer

BACKGROUND

This study aimed to identify the clinical predictors for the response of patients with mCRPC to ARATs.

MATERIALS AND METHODS

We retrospectively collected data on consecutive patients who were diagnosed with mCRPC and underwent ARAT treatment during this stage of the disease. Clinical parameters were obtained through medical chart reviews. ARAT failure was defined as a continuous increase in the serum prostate-specific antigen (PSA) level above nadir to > 2 ng/mL, accompanied by radiographic progression. ARAT failure-free survival and overall survival were assessed through Kaplan-Meier survival analysis and Cox regression survival analysis. Nomogram analysis based on significant predictors of ARAT failure-free survival was performed.

RESULTS

In total, 319 patients with mCRPC who underwent ARAT were included. Multivariate analysis revealed that age, International Society of Urological Pathology (ISUP) grading, and chemotherapy-naïve status were significant predictors of ARAT failure-free survival. For overall survival, age, ISUP grading, and nadir PSA level during androgen deprivation therapy (ADT) were significant predictors. Through nomogram analysis based on age, ISUP grading, and chemotherapy-naïve status, the likelihood of ARAT duration being more or less than 1 year could be predicted.

CONCLUSION

For mCRPC patients, being older, having ISUP Grade 5 cancer, and having a history of chemotherapy were associated with a shorter duration of response to next-line ARATs. Therefore, other therapeutic agents should be prioritized for such patients. Notably, among the included patients, those who were older, had a higher ISUP grade and a higher nadir PSA level during ADT exhibited worse overall survival.

Patient Preferences for Attributes of Androgen Deprivation Therapies in Prostate Cancer: A Discrete Choice Experiment with Latent Class Analysis

INTRODUCTION

Medical androgen deprivation therapy (ADT) options have expanded for patients with advanced prostate cancer (PC). Historically, ADT was primarily available in long-acting injectable formulations. In 2020, the first oral formulation was US Food and Drug Administration-approved for adults with advanced PC. This study's aim was to assess patient preferences for attributes of medical ADT, including mode of administration, side effects, impact on sexual interest, and out-of-pocket (OOP) costs, and to segment respondents into distinct groups based on their treatment choice patterns.

METHODS

A cross-sectional survey was conducted among US residents aged > 40 years with PC, employing a discrete choice experiment to assess preferences for ADT attributes. For each choice task, respondents were asked to select the hypothetical treatment profile that they preferred out of two presented. Latent class analysis (LCA) was conducted to estimate attribute-level preference weights and calculate attribute relative importance for groups of respondents with similar treatment preferences.

RESULTS

A total of 304 respondents completed the survey (mean age 64.4 years). LCA identified four preference groups, named according to the attribute each group considered most important: Sexual interest, Cost-sensitive, Favors daily pill, and Favors injection. Most respondents in the Sexual interest group were < 65 years, while the Cost-sensitive group was mostly ≥ 65 years. Favors daily pill had the highest proportion of ADT-naïve individuals. On average, respondents in these groups preferred an oral medication. Favors injection, which had the highest proportion of ADT-experienced individuals, preferred infrequent intramuscular injections, lower chance of post-ADT testosterone recovery, and lower OOP cost.

CONCLUSION

Respondents differed in their preferences regarding ADT attributes, highlighting the need for patient involvement in their treatment decisions. Effective communication between healthcare providers and patients about the benefits and risks of available therapies should be encouraged to ensure that patients receive the PC treatment that best meets their needs.

The impact of neoadjuvant relugolix on multi-dimensional patient-reported fatigue

Introduction

Androgen deprivation therapy has been shown to improve cancer control when combined with radiotherapy. Relugolix is an oral GnRH receptor antagonist that achieves rapid profound testosterone suppression, which may increase the perception and/or impact of fatigue. This study sought to evaluate neoadjuvant relugolix-induced fatigue in prostate cancer patients prior to the start of stereotactic body radiation therapy (SBRT).

Methods

Relugolix was initiated at least two months before SBRT. The 13-item Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) questionnaire was collected at baseline and one hour prior to SBRT initiation. A five-point scale was used to score individual items. Overall scores range from 0-52 and individual item scores were converted to 0-100, with higher scores reflecting less fatigue. Five "experience" items explored self-perceptions of fatigue, and eight "impact" items sought to evaluate the effect of fatigue on daily activities. Items were evaluated for statistical significance (paired t-test, p < 0.05) and clinical significance (minimally important difference (MID); 0.5 standard deviation from baseline).

Results

Between March 2021 to December 2023, 89 men were treated at Georgetown with neoadjuvant relugolix and SBRT. Mean age was 71 years (range: 49-87). Median initiation of relugolix was 4.5 months prior to SBRT (range: 2-14.2 months). 93% patients achieved castration (testosterone levels ≤ 50 ng/dL) and 85% patients achieved profound castration (testosterone levels ≤ 20 ng/dL). 87 patients completed the FACIT-F questionnaire, with an average overall score of 45.6 at baseline and 41.0 at SBRT initiation. This difference was statistically and clinically significant (p < 0.01, MID = 3.55). Patients experienced an increase in fatigue for 12 of 13 items, with statistically significant changes for 11 items. Three of five experience items showed a clinically significant increase in fatigue. Only two of eight impact items were clinically significant.

Discussion

Our study shows that relugolix significantly increases fatigue, affecting multiple areas of life. While the fatigue does not appear to generally impact a patient's ability to carry out normal activities, patients demonstrate frustration with being too tired for these activities. It is essential for clinicians to counsel prostate cancer patients on the impact of neoadjuvant relugolix on quality-of-life issues like fatigue.

Efficacy, tolerability, and safety of teverelix DP in patients with advanced prostate cancer: A multicenter, open-label, phase 2 trial

BACKGROUND

Teverelix drug product (DP) is a novel injectable gonadotropin-releasing hormone antagonist.

METHODS

An adaptive phase 2, open-label, multicenter trial was conducted in patients with advanced prostate cancer to evaluate the efficacy and safety of a combined subcutaneous (SC) and intramuscular (IM) loading dose regimen of teverelix DP of 120 mg SC + 120 mg IM (Group 1; N = 9) or 180 mg SC + 180 mg IM (Group 2; N = 41) administered at a single visit, followed by 6-weekly SC maintenance doses of 120 mg (Group 1) or 180 mg (Group 2), up to Day 168. The primary endpoint was the proportion of patients achieving castration levels with serum testosterone <0.5 ng/mL at Day 28 with a target castration rate of 90%. Injection sites were inspected by the investigator at every visit and reactions (ISRs) were proactively recorded.

RESULTS

The target castration rate was reached in Group 2 (97.5%) but not in Group 1 (62.5%). The castration rates were not maintained to Day 42 (Group 2: 82.5%; Group 1: 50.0%). Suppression of testosterone to castrate levels occurred rapidly (median time: 2 days for both groups). Suppression of testosterone, prostate-specific antigen, follicle-stimulating hormone, and luteinizing hormone was sustained throughout the treatment period, being more prominent with the higher dose. The adverse event (AE) profile was similar between groups. The most common AEs were injection-site induration (n = 40: 80.0%), injection-site erythema (n = 35: 70.0%), and hot flush (n = 21: 42.0%). Most ISRs were Grade 1.

CONCLUSION

Overall, the teverelix DP doses were generally well-tolerated but did not adequately maintain castration levels.

Addressing the risk and management of cardiometabolic complications in prostate cancer patients on androgen deprivation therapy and androgen receptor axis-targeted therapy: consensus statements from the Hong Kong Urological Association and the Hong Kong Society of Uro-Oncology

Background

Androgen deprivation therapy (ADT) is the foundational treatment for metastatic prostate cancer (PCa). Androgen receptor (AR) axis-targeted therapies are a new standard of care for advanced PCa. Although these agents have significantly improved patient survival, the suppression of testosterone is associated with an increased risk of cardiometabolic syndrome. This highlights the urgency of multidisciplinary efforts to address the cardiometabolic risk of anticancer treatment in men with PCa.

Methods

Two professional organizations invited five urologists, five clinical oncologists, and two cardiologists to form a consensus panel. They reviewed the relevant literature obtained by searching PubMed for the publication period from April 2013 to April 2023, to address three discussion areas: (i) baseline assessment and screening for risk factors in PCa patients before the initiation of ADT and AR axis-targeted therapies; (ii) follow-up and management of cardiometabolic complications; and (iii) selection of ADT agents among high-risk patients. The panel convened four meetings to discuss and draft consensus statements using a modified Delphi method. Each drafted statement was anonymously voted on by every panelist.

Results

The panel reached a consensus on 18 statements based on recent evidence and expert insights.

Conclusion

These consensus statements serve as a practical recommendation for clinicians in Hong Kong, and possibly the Asia-Pacific region, in the management of cardiometabolic toxicities of ADT or AR axis-targeted therapies in men with PCa.

Prevalence of Preexisting Cardiovascular Diseases in Prostate Cancer Patients and Cardiac Risks of Hormonal Therapy

Background

Cardiovascular diseases (CVDs) are a prominent cause of mortality in prostate cancer patients. However, it has been reported that patients with preexisting CVDs are at greater risk. Literature on the magnitude of this problem in Saudi Arabia is lacking.

Objectives

To measure the prevalence of prostate cancer patients with preexisting CVDs in our population and to elucidate the possible risk factors of new cardiovascular events (CVEs) in patients who received androgen deprivation therapy (ADT).

Materials and Methods

This retrospective study included all patients newly diagnosed with prostate cancer at a tertiary hospital in the Eastern Province of Saudi Arabia from October 2008 to January 2019. The prevalence of preexisting cardiovascular diseases in these patients were determined. In addition, the incidence of new CVEs after initiating ADT was determined along with the risk factors for the same.

Results

The prevalence of preexisting CVD in our cohort was 16%. About 6% of the patients who received ADT had CVEs after a median follow-up of 39 months (IQR: 11-49 months). In the univariate analysis, hyperlipidemia (P = 0.002), stroke (P = 0.001), peripheral vascular disease (P = <0.001), cardiac patients with stents (P = <0.001), and cardiac patients without stent (P = <0.001) were significant risk factors of new CVEs after initiating ADT. However, in the multivariate regression analysis, only history of stroke and CVD (with or without stent) were found to be significant risk factors of new CVEs after initiating ADT (P = 0.01).

Conclusion

About one-fifth of the prostate cancer patients had preexisting CVDs. This study also found that luteinizing hormone-releasing hormone agonist could be a risk factor for new CVEs.

Cardiovascular risk of gonadotropin-releasing hormone antagonist versus agonist in men with prostate cancer: an observational study in Taiwan

BACKGROUND

The impact of gonadotropin-releasing hormone (GnRH) antagonist and agonist (GnRHa) treatment on cardiovascular disease (CVD) risk in prostate cancer (PCa) remains inconclusive due to conflicting findings. We compared the effects of GnRH antagonist and GnRHa treatments on CVD risk in patients with PCa and pre-existing CVD, in a Taiwan population-based database.

METHODS

We assessed the risk of major adverse CV events (MACE: ischemic heart disease [IHD], stroke, congestive heart failure [CHF] or all cause deaths) and composite CV events (IHD, stroke, CHF or CV deaths) occurring ≥90 days after androgen deprivation therapy (ADT) initiation in patients with PCa after 90 days of treatment with either GnRH antagonist (degarelix; n = 499) or GnRHa (goserelin, leuprolide, triptorelin; n = 15,127). Patients identified with pre-existing CVD had received cardiac therapy for IHD, reported a stroke or CHF within a year before ADT initiation. Adjusted hazard ratios (aHR) and 95% confidence interval (CI) were obtained for MACE and composite CV events risk after adjusting for age, baseline status of diabetes, hypertension and treatments received.

RESULTS

All GnRH antagonist-treated patients showed lower risk of composite CV events than the GnRHa-treated patients. The lower composite CV events risk associated with GnRH antagonist was also observed in patients with metastasis at diagnosis (aHR 0.16; 95% CI, 0.04-0.38; p = 0.013) and those receiving ADT for more than six months (aHR 0.30; 95% CI, 0.16-0.54; p < 0.0001). In patients with pre-existing CVD, the MACE risk was 33% lower (aHR 0.67; 95% CI, 0.46-0.96; p = 0.0299) and composite CV events risk was 84% lower (aHR 0.16; 95% CI, 0.05-0.50; p = 0.0017) in GnRH antagonist-treated than the GnRHa-treated patients.

CONCLUSIONS

In patients with PCa and pre-existing CVD, GnRH antagonist use was associated with lower risks for composite CV events and MACE compared with GnRHa.

Profile of Relugolix in the Management of Advanced Hormone-Sensitive Prostate Cancer: Design, Development, and Place in Therapy

Androgen deprivation therapy, primarily via a gonadotropin-releasing hormone receptor agonist or antagonist together with or without an androgen receptor antagonist, remains the mainstay of medical treatment for advanced prostate cancer. Meanwhile, relugolix has been developed as the first orally active, non-peptide, selective antagonist for the gonadotropin-releasing hormone receptor. Previous randomized studies involving patients with prostate cancer have demonstrated comparable efficacy in androgen suppression between relugolix vs other gonadotropin-releasing hormone antagonists or agonists. This review summarizes available data on the design and development of relugolix and its therapeutic application, and discusses if relugolix represents a promising oral alternative to injectable androgen deprivation therapy. Based on current published evidence, further investigation is likely required to determine the actual clinical benefits of relugolix therapy against prostate cancer.

Safety, Pharmacokinetic and Pharmacodynamic Evaluation of Teverelix for the Treatment of Hormone-Sensitive Advanced Prostate Cancer: Phase 2 Loading-Dose-Finding Studies

Background and objectives: Teverelix drug product (DP) is a gonadotropin-releasing hormone antagonist in development for the treatment of patients with prostate cancer in whom androgen deprivation therapy is indicated. The aim of this paper is to present the results of five Phase 2 studies that assessed the pharmacokinetics, pharmacodynamics, efficacy and safety of different loading dose regimens of teverelix DP. Methods: Five single-arm, uncontrolled clinical trials were conducted in patients with advanced prostate cancer. The five different loading dose regimens of teverelix DP tested were (a) a single 90 mg subcutaneous (SC) injection of teverelix DP given on 3 consecutive days (Days 0, 1 and 2); (b) a single 90 mg intramuscular (IM) injection of teverelix DP given 7 days apart (Days 0 and 7); (c) a single 120 mg SC injection of teverelix DP given on 2 consecutive days (Days 0 and 1); (d) 2 × 60 mg SC injections of teverelix DP given on 3 consecutive days (Days 0, 1 and 2), and (e) 2 × 90 mg SC injections of teverelix DP given on 3 consecutive days (Days 0, 1 and 2). The primary efficacy parameter was the duration of action of an initial loading dose regimen in terms of suppression of testosterone to below the castration level (0.5 ng/mL). Results: Eighty-two patients were treated with teverelix DP. Two regimens (90 mg and 180 mg SC on 3 consecutive days) had a mean duration of castration of 55.32 days and 68.95 days with >90% of patients having testosterone levels < 0.5 ng/mL at Day 28. The mean onset of castration for the SC regimens ranged from 1.10 to 1.77 days, while it was slower (2.4 days) with IM administration. The most common adverse event (AE) was injection site reaction. No AEs of severe intensity were reported. Conclusions: Teverelix DP is safe and well tolerated. Castrate levels of testosterone can be rapidly achieved following the subcutaneous injection of teverelix DP on 3 consecutive days. Streamlining of the administration of the loading dose and identifying a suitable maintenance dose will be investigated in future trials.

Regular use of aspirin is associated with a lower cardiovascular risk in prostate cancer patients receiving gonadotropin-releasing hormone therapy

Gonadotropin-releasing hormone (GnRH) therapy has been known to increase risks of major adverse cardiovascular and cerebrovascular events (MACCEs). Herein, we aim to estimate whether regular use of aspirin attenuates risks of MACCEs in prostate cancer patients receiving GnRHs. Using Taiwanese National Health Insurance Research Database (NHIRD), we identified 7719 patients diagnosed with prostate cancer who were either aspirin-naïve, received irregular or regular aspirin from 2008 to 2015. Through a multivariable logistic regression model, we investigated the impact of aspirin on MACCEs. Compared with nonusers and irregular users, most patients receiving regular aspirin were older and had more comorbidities. The crude incidence of one-year MACCEs was lowest in aspirin nonusers but highest in irregular users of aspirin compared with regular users of aspirin (2.65% vs. 4.41% vs. 2.85%, p=0.0099). After adjusting for age, cancer stage and comorbidities, irregular aspirin users had a higher risk of one-year MACCEs (adjusted OR: 1.33; 95% CI: 0.93-1.90, p=0.1139) than aspirin nonusers, but conversely, there was a trend of reducing the risk of MACCEs among those who received regular aspirin (adjusted OR: 0.79; 95% CI: 0.44-1.42, p=0.4256). In the subgroup analysis, there were age- and cancer stage-independent higher risks of MACCEs in patients who took aspirin irregularly compared to those in patients who did not take aspirin. The risks were attenuated in patients receiving regular aspirin. Collectively, regular use of aspirin presented a trend of reducing risks of MACCEs in prostate cancer patients receiving GnRHs. However, irregular use of aspirin diminished the benefits.

Safety of androgen therapy in men with prostate cancer

Prostate cancer is one of the most frequently diagnosed malignancies in men worldwide and the life expectancy for men with prostate cancer is improving due to advancements in diagnostics and treatment. Male hypogonadism is associated with obesity, diabetes, and other comorbidities and also has been linked with increasing age; the primary therapy modality for this condition is testosterone replacement therapy (TRT). There are concerns that testosterone therapy may cause prostate cancer disease progression. However, contemporary evidence suggests that testosterone replacement therapy may be safe in specific groups of patients with prostate cancer. This chapter will summarise the contemporary literature regarding TRT use in hypogonadal men with prostate cancer, including limitations and future research goals.

Anti-Androgen Receptor Therapies in Prostate Cancer: A Brief Update and Perspective

Prostate cancer is a major health issue in western countries and is the second leading cause of cancer death in American men. Prostate cancer depends on the androgen receptor (AR), a transcriptional factor critical for prostate cancer growth and progression. Castration by surgery or medical treatment reduces androgen levels, resulting in prostatic atrophy and prostate cancer regression. Thus, metastatic prostate cancers are initially managed with androgen deprivation therapy. Unfortunately, prostate cancers rapidly relapse after castration therapy and progress to a disease stage called castration-resistant prostate cancer (CRPC). Currently, clinical treatment for CRPCs is focused on suppressing AR activity with antagonists like Enzalutamide or by reducing androgen production with Abiraterone. In clinical practice, these treatments fail to yield a curative benefit in CRPC patients in part due to AR gene mutations or splicing variations, resulting in AR reactivation. It is conceivable that eliminating the AR protein in prostate cancer cells is a promising solution to provide a potential curative outcome. Multiple strategies have emerged, and several potent agents that reduce AR protein levels were reported to eliminate xenograft tumor growth in preclinical models via distinct mechanisms, including proteasome-mediated degradation, heat-shock protein inhibition, AR splicing suppression, blockage of AR nuclear localization, AR N-terminal suppression. A few small chemical compounds are undergoing clinical trials combined with existing AR antagonists. AR protein elimination by enhanced protein or mRNA degradation is a realistic solution for avoiding AR reactivation during androgen deprivation therapy in prostate cancers.

[Factors influencing the choice of androgen deprivation therapy for patients with hormone-sensitive prostate cancer : Results of the ProComD study]

BACKGROUND

Androgen deprivation therapy (ADT) with a GnRH agonist or the GnRH antagonist degarelix is a central component in the treatment of prostate cancer (PCa). Little is currently known regarding the decision criteria. Knowledge of these could improve the success of treatment in the future.

OBJECTIVES

To identify factors influencing the treatment decision in patients with hormone-sensitive prostate cancer receiving ADT and to determine the incidence of concomitant disease in both treatment groups.

METHODS

The two-arm, prospective, non-interventional study "ProComD" was conducted from September 2014 to June 2019 at 80 study centers in Germany. After the therapy decision was made, patients with hormone-sensitive prostate cancer needing ADT were included in the study. Data were collected during routine visits.

RESULTS

Data from 413 patients were evaluated (degarelix N = 268; GnRH agonists N = 145). Key factors influencing the therapy decision for both treatment options included comorbidities (42% of all patients), compliance (64%), and age (81%). The source of information consulted most frequently regarding existing comorbidities was the patient's medical history conducted by the treating urologist themselves (65% in both groups). For patients with pre-existing cardiovascular diseases, the doctor's letter (45.8% degarelix vs. 38.9% GnRH agonists) or the medical history questionnaire (38.9% degarelix vs. 20% GnRH agonists) was additionally taken into account.

CONCLUSION

Comorbidities along with age and compliance are among the key factors influencing the treatment decisions made by urologists.

Lysine Acetyltransferases and Their Role in AR Signaling and Prostate Cancer

The development and growth of a normal prostate gland, as well as its physiological functions, are regulated by the actions of androgens through androgen receptor (AR) signaling which drives multiple cellular processes including transcription, cellular proliferation, and apoptosis in prostate cells. Post-translational regulation of AR plays a vital role in directing its cellular activities via modulating its stability, nuclear localization, and transcriptional activity. Among various post-translational modifications (PTMs), acetylation is an essential PTM recognized in AR and is governed by the regulated actions of acetyltransferases and deacetyltransferases. Acetylation of AR has been identified as a critical step for its activation and depending on the site of acetylation, the intracellular dynamics and activity of the AR can be modulated. Various acetyltransferases such as CBP, p300, PCAF, TIP60, and ARD1 that are known to acetylate AR, may directly coactivate the AR transcriptional function or help to recruit additional coactivators to functionally regulate the transcriptional activity of the AR. Aberrant expression of acetyltransferases and their deregulated activities have been found to interfere with AR signaling and play a key role in development and progression of prostatic diseases, including prostate cancer (PCa). In this review, we summarized recent research advances aimed at understanding the role of various lysine acetyltransferases (KATs) in the regulation of AR activity at the level of post-translational modifications in normal prostate physiology, as well as in development and progression of PCa. Considering the critical importance of KATs in modulating AR activity in physiological and patho-physiological context, we further discussed the potential of targeting these enzymes as a therapeutic option to treat AR-related pathology in combination with hormonal therapy.

Relugolix, an oral gonadotropin-releasing hormone antagonist for the treatment of prostate cancer

Androgen deprivation therapy using gonadotropin-releasing hormone (GnRH) analogues is standard treatment for intermediate and advanced prostate cancer. GnRH agonist therapy results in an initial testosterone flare, and increased metabolic and cardiovascular risks. The GnRH antagonist relugolix is able to reduce serum testosterone levels in men with prostate cancer without inducing testosterone flare. In the HERO Phase III trial, relugolix was superior to leuprolide acetate at rapidly reducing testosterone and continuously suppressing testosterone, with faster post-treatment recovery of testosterone levels. Relugolix was associated with a 54% lower incidence of major adverse cardiovascular events than leuprolide acetate. As the first oral GnRH antagonist approved for the treatment of advanced prostate cancer, relugolix offers a new treatment option.

Enzalutamide-Induced Upregulation of PCAT6 Promotes Prostate Cancer Neuroendocrine Differentiation by Regulating miR-326/HNRNPA2B1 Axis

Our previous studies have demonstrated that Enzalutamide-induced upregulation of long non-coding RNA p21 (lncRNA-p21) facilitates prostate cancer (PCa) neuroendocrine differentiation (NED). Given the important role of lncRNAs in PCa pathogenesis, and given that lots of lncRNAs are dys-regulated in neuroendocrine PCa (NEPC) patients, we next explored the biological function and underlying mechanism of lncRNA-PCAT6 (PCAT6) in mediating Enzalutamide-induced NED. The level of PCAT6 in Enzalutamide-treated PCa cells and NEPC samples were assessed using quantitative RT-PCR (qPCR). The effect of PCAT6 on PCa cell proliferation, invasion, and NED was evaluated through CCK-8, transwell, qPCR, western blot analysis, Xenograft mouse model, and in vivo lung metastasis model. We found that PCAT6 was highly expressed in NE-like cells (PC3, DU145, and NCI-H660) compared with androgen-sensitive LNCaP cells. PCAT6 was also highly expressed in NEPC tissues. Enzalutamide treatment resulted in a significant increase of PCAT6 level in a dose- and time-dependent fashion. Functionally, PCAT6 overexpression promoted NED of C4-2 cells, as evidenced by an increased expression of NE markers (NSE, ChgA, and SYP), whereas PCAT6 knockdown in NCI-H661 cells repressed NED. Furthermore, PCAT6 overexpression promoted PCa cell proliferation and invasion in vitro and in vivo. Mechanistically, PCAT6 functioned as competing endogenous (ce) RNA via absorbing miR-326, thus resulting in a de-suppression of Hnrnpa2b1 target gene. The current results demonstrate that PCAT6 acted as a tumor activator in PCa progression by sponging miR-326 and increasing Hnrnpa2b1 expression and that the PCAT6/miR-326/Hnrnpa2b1 signaling might be a new therapeutic target for PCa.

Dissecting the Hormonal Signaling Landscape in Castration-Resistant Prostate Cancer

Understanding the molecular mechanisms underlying prostate cancer (PCa) progression towards its most aggressive, castration-resistant (CRPC) stage is urgently needed to improve the therapeutic options for this almost incurable pathology. Interestingly, CRPC is known to be characterized by a peculiar hormonal landscape. It is now well established that the androgen/androgen receptor (AR) axis is still active in CRPC cells. The persistent activity of this axis in PCa progression has been shown to be related to different mechanisms, such as intratumoral androgen synthesis, AR amplification and mutations, AR mRNA alternative splicing, increased expression/activity of AR-related transcription factors and coregulators. The hypothalamic gonadotropin-releasing hormone (GnRH), by binding to its specific receptors (GnRH-Rs) at the pituitary level, plays a pivotal role in the regulation of the reproductive functions. GnRH and GnRH-R are also expressed in different types of tumors, including PCa. Specifically, it has been demonstrated that, in CRPC cells, the activation of GnRH-Rs is associated with a significant antiproliferative/proapoptotic, antimetastatic and antiangiogenic activity. This antitumor activity is mainly mediated by the GnRH-R-associated Gαi/cAMP signaling pathway. In this review, we dissect the molecular mechanisms underlying the role of the androgen/AR and GnRH/GnRH-R axes in CRPC progression and the possible therapeutic implications.

Aging and sex hormones in males

Over the past two decades several large cohort studies have been performed to disclose the changes of sex hormone in elderly and their clinical significance. Beyond the decline of total testosterone, aging is accompanied by a sex hormone binding globulin (SHBG) increase, a steeper free testosterone decline, while gonadotropins may be increased or inappropriately normal, with important contribution of comorbidities (e.g., obesity) to these changes. Actually, it has become firm the concept that the biochemical finding of testosterone deficiency alone is not sufficient for diagnosing hypogonadism in older men. The definition of late-onset hypogonadism (LOH) includes low serum testosterone levels coupled with signs and symptoms related to hypogonadism. Indeed, the combination of multiple factors all contributing to the testosterone decline, with other concurrent comorbidities further overlapping, makes the clinical correlates of LOH highly heterogeneous. For all these reasons both the diagnosis and the therapeutic management of LOH, especially the decision about starting testosterone replacement treatment, remain challenging.

Gonadotropin-Releasing Hormone Receptors in Prostate Cancer: Molecular Aspects and Biological Functions

Pituitary Gonadotropin-Releasing Hormone receptors (GnRH-R) mediate the activity of the hypothalamic decapeptide GnRH, thus playing a key role in the regulation of the reproductive axis. Early-stage prostate cancer (PCa) is dependent on serum androgen levels, and androgen-deprivation therapy (ADT), based on GnRH agonists and antagonists, represents the standard therapeutic approach for PCa patients. Unfortunately, the tumor often progresses towards the more aggressive castration-resistant prostate cancer (CRPC) stage. GnRH receptors are also expressed in CRPC tissues, where their binding to both GnRH agonists and antagonists is associated with significant antiproliferative/proapoptotic, antimetastatic and antiangiogenic effects, mediated by the Gαi/cAMP signaling cascade. GnRH agonists and antagonists are now considered as an effective therapeutic strategy for CRPC patients with many clinical trials demonstrating that the combined use of these drugs with standard therapies (i.e., docetaxel, enzalutamide, abiraterone) significantly improves disease-free survival. In this context, GnRH-based bioconjugates (cytotoxic drugs covalently linked to a GnRH-based decapeptide) have been recently developed. The rationale of this treatment is that the GnRH peptide selectively binds to its receptors, delivering the cytotoxic drug to CRPC cells while sparing nontumor cells. Some of these compounds have already entered clinical trials.