Cardiovascular risk with androgen deprivation therapy for prostate cancer: potential mechanisms

Androgen Deprivation Therapy/Androgen Receptor Signaling Inhibitor Treatments for Prostate Cancer: Pathophysiology and Review of Effects on Cardiovascular Disease

Androgen deprivation therapy is the cornerstone of systemic management for prostate cancer but is associated with multiple adverse effects that must be considered during treatment. These effects occur because of the profound hypogonadism that is induced from lack of testosterone or due to the medications used in the treatment or in combination with androgen receptor signaling inhibitors. This article critically reviews the associations between androgen deprivation therapy, androgen receptor signaling inhibitors, and cardiovascular complications such as prolonged QT interval, atrial fibrillation, heart failure, atherosclerosis, coronary heart disease, venous thromboembolism, and peripheral arterial occlusive disease. These unfavorable outcomes reinforce the need for regular cardiovascular screening of patients undergoing androgen deprivation for the management of prostate cancer.

FSH Is Responsible for Androgen Deprivation Therapy-Associated Atherosclerosis in Mice by Exaggerating Endothelial Inflammation and Monocyte Adhesion

BACKGROUND

Androgen deprivation therapy (ADT) is the mainstay treatment for advanced prostate cancer. But ADTs with orchiectomy and gonadotropin-releasing hormone (GnRH) agonist are associated with increased risk of cardiovascular diseases, which appears less significant with GnRH antagonist. The difference of follicle-stimulating hormone (FSH) in ADT modalities is hypothesized to be responsible for ADT-associated cardiovascular diseases.

METHODS

We administered orchiectomy, GnRH agonist, or GnRH antagonist in male ApoE-/- mice fed with Western diet and manipulated FSH levels by testosterone and FSH supplementation or FSH antibody to investigate the role of FSH elevation on atherosclerosis. By combining lipidomics, in vitro study, and intraluminal FSHR (FSH receptor) inhibition, we delineated the effects of FSH on endothelium and monocytes and the underlying mechanisms.

RESULTS

Orchiectomy and GnRH agonist, but not GnRH antagonist, induced long- or short-term FSH elevation and significantly accelerated atherogenesis. In orchiectomized and testosterone-supplemented mice, FSH exposure increased atherosclerosis. In GnRH agonist-treated mice, blocking of short FSH surge by anti-FSHβ antibody greatly alleviated endothelial inflammation and delayed atherogenesis. In GnRH antagonist-treated mice, FSH supplementation aggravated atherogenesis. Mechanistically, FSH, synergizing with TNF-α (tumor necrosis factor alpha), exacerbated endothelial inflammation by elevating VCAM-1 (vascular cell adhesion protein 1) expression through the cAMP/PKA (protein kinase A)/CREB (cAMP response element-binding protein)/c-Jun and PI3K (phosphatidylinositol 3 kinase)/AKT (protein kinase B)/GSK-3β (glycogen synthase kinase 3 beta)/GATA-6 (GATA-binding protein 6) pathways. In monocytes, FSH upregulated CD29 (cluster of differentiation 29) expression via the PI3K/AKT/GSK-3β/SP1 (specificity protein 1) pathway and promoted monocyte-endothelial adhesion both in vitro and in vivo. Importantly, FSHR knockdown by shRNA in endothelium of carotid arteries markedly reduced GnRH agonist-induced endothelial inflammation and atherosclerosis in mice.

CONCLUSIONS

FSH is responsible for ADT-associated atherosclerosis by exaggerating endothelial inflammation and promoting monocyte-endothelial adhesion.

Serum DHEA and Testosterone Levels Associate Inversely With Coronary Artery Calcification in Elderly Men

CONTEXT

Epidemiological and preclinical data support cardiovascular, mainly protective, effects of sex steroids in men, but the mechanisms underlying the cardiovascular actions of sex steroids are poorly understood. Vascular calcification parallels the development of atherosclerosis, but is increasingly recognized as a diversified, highly regulated process, which itself may have pathophysiological importance for clinical cardiovascular events.

OBJECTIVE

To investigate the association between serum sex steroids and coronary artery calcification (CAC) in elderly men.

METHODS

We used gas chromatography tandem mass spectrometry to analyze a comprehensive sex steroid profile, including levels of dehydroepiandrosterone (DHEA), androstenedione, estrone, testosterone, estradiol, and dihydrotestosterone, in men from the population-based AGES-Reykjavik study (n = 1287, mean 76 years). Further, sex hormone-binding globulin (SHBG) was assayed and bioavailable hormone levels calculated. CAC score was determined by computed tomography. The main outcome measures were cross-sectional associations between dehydroepiandrosterone, androstenedione, estrone, testosterone, dihydrotestosterone, and estradiol and quintiles of CAC.

RESULTS

Serum levels of DHEA, androstenedione, testosterone, dihydrotestosterone, and bioavailable testosterone showed significant inverse associations with CAC, while estrone, estradiol, bioavailable estradiol, and SHBG did not. DHEA, testosterone, and bioavailable testosterone remained associated with CAC after adjustment for traditional cardiovascular risk factors. In addition, our results support partially independent associations between adrenal-derived DHEA and testes-derived testosterone and CAC.

CONCLUSION

Serum levels of DHEA and testosterone are inversely associated with CAC in elderly men, partially independently from each other. These results raise the question whether androgens from both the adrenals and the testes may contribute to male cardiovascular health.

Appropriateness and complications of androgen deprivation therapy for prostate cancer: Can we do better? A retrospective observational analysis from a referral center

INTRODUCTION

Androgen deprivation therapy (ADT) is the key of medical treatment for advanced prostate cancer (PCa), especially in elderly patients. However, the adherence of ADT prescription to current guidelines is not optimal and must be balanced against possible side effects. Aim of this study was to evaluate the prescriptive appropriateness of ADT and ADT-related adverse events in a referral center for PCa.

METHODS

Five hundred fifty six patients who received an outpatient prescription for ADT from 2014 to 2018 were retrospectively identified from an administrative database. Only standard ADT was considered, including GnRH agonists, GnRH antagonists, and antiandrogens. Prescriptive appropriateness was defined according to the last European Association of Urology (EAU) guidelines. Our cohort was stratified according to age categories and patient follow-up was updated.

RESULTS

Four hundred twenty five patients were available for analysis. Mean age was 80 years; 96.3% of our patients fell in the "elderly" category. There was a predominance of GnRH agonists over the antagonists (84.9% vs 13%). 15.5% of ADTs did not have an appropriate indication according to guidelines. Patient compliance to ADT was evaluated as good in 372 (87.5%) cases. ADT-related complications were detected in 166 (39%) patients: bone, cardiovascular, and other complications were reported in 7.3%, 8.9%, and 19% of patients. Progression of disease was noted in 165 (38.8%) cases during ADT. At last follow-up, 124 (30.1%) patients were deceased.

CONCLUSIONS

In a referral center, most ADT prescriptions followed EAU guidelines, but a non-negligible proportion still did not fall within these indications, exposing patients to unnecessary side effects. Compliance to ADT was generally good with a predominant use of GnRH agonists. Tolerance to ADT was fair, even if standardized reports were lacking.

Deficiency of mature B cells does not alter the atherogenic response to castration in male mice

Testosterone deficiency in men is associated with increased atherosclerosis burden and increased cardiovascular risk. In male mice, testosterone deficiency induced by castration increases atherosclerosis as well as mature B cell numbers in spleen. As B cells are potentially pro-atherogenic, we hypothesized that there may be a link between these effects. To address whether mature B cell deficiency alter the atherogenic response to castration, we studied B cell-deficient μMT and genotype control male mice on an atherosclerosis-prone Apoe^-/- background that were castrated or sham-operated pre-pubertally and fed a high-fat diet between 8 and 16 weeks of age to accelerate atherosclerosis development. Genotype did not affect the effects of castration on body weight or weights of fat depots and there were no differences in serum cholesterol levels across the four groups. Atherosclerosis assessed by quantification of lesion area in serial sections of the aortic root was significantly increased by castration and by the μMT mutation, with no significant interaction between genotype and surgery. In conclusion, castration evokes a similar atherogenic response in B cell-deficient μMT and control mice. These data suggest that atherogenesis following castration is unrelated to the effects of androgens on mature B cell numbers.

Low Progesterone and Low Estradiol Levels Associate With Abdominal Aortic Aneurysms in Men

CONTEXT

Male sex is a major risk factor for abdominal aortic aneurysms (AAA) but few studies have addressed associations between sex hormone levels and AAA.

OBJECTIVE

We aimed to describe the associations between serum sex steroids and early, screening-detected AAA in men.

METHODS

We validated a high-sensitivity liquid chromatography-tandem mass spectrometry assay for comprehensive serum sex hormone profiling. This assay was then employed in a case-control study including 147 men with AAA (infrarenal aorta ≥ 30 mm) and 251 AAA-free controls recruited at the general population-based ultrasound screening for AAA in 65-year-old Swedish men.

OUTCOMES INCLUDED

associations between dehydroepiandrosterone, progesterone, 17α-hydroxyprogesterone, androstenedione, estrone, testosterone, dihydrotestosterone, and estradiol and AAA presence.

RESULTS

Dehydroepiandrosterone, progesterone, 17α-hydroxyprogesterone, testosterone, and estradiol, but not the other hormones, were lower in men with AAA. In models with adjustments for known AAA risk factors and comorbidity, only progesterone (odds ratio per SD decrease 1.62 [95% CI, 1.18-2.22]) and estradiol (1.40 [95% CI, 1.04-1.87]) remained inversely associated with the presence of AAA. Progesterone and estradiol contributed with independent additive information for prediction of AAA presence; compared with men with high (above median) levels, men with low (below median) levels of both hormones had a 4-fold increased odds ratio for AAA (4.06 [95% CI, 2.25-7.31]).

CONCLUSION

Measured by a high-performance sex steroid assay, progesterone and estradiol are inversely associated with AAA in men, independent of known risk factors. Future studies should explore whether progesterone and estradiol, which are important reproductive hormones in women, are protective in human AAA.

Cardiovascular Safety of Degarelix Versus Leuprolide in Patients With Prostate Cancer: The Primary Results of the PRONOUNCE Randomized Trial

BACKGROUND

The relative cardiovascular safety of gonadotropin-releasing hormone (GnRH) antagonists compared with GnRH agonists in men with prostate cancer and known atherosclerotic cardiovascular disease remains controversial.

METHODS

In this international, multicenter, prospective, randomized, open-label trial, men with prostate cancer and concomitant atherosclerotic cardiovascular disease were randomly assigned 1:1 to receive the GnRH antagonist degarelix or the GnRH agonist leuprolide for 12 months. The primary outcome was the time to first adjudicated major adverse cardiovascular event (composite of death, myocardial infarction, or stroke) through 12 months.

RESULTS

Because of slower-than-projected enrollment and fewer-than-projected primary outcome events, enrollment was stopped before the 900 planned participants were accrued. From May 3, 2016, to April 16, 2020, a total of 545 patients from 113 sites across 12 countries were randomly selected. Baseline characteristics were balanced between study groups. The median age was 73 years, 49.8% had localized prostate cancer; 26.3% had locally advanced disease, and 20.4% had metastatic disease. A major adverse cardiovascular event occurred in 15 (5.5%) patients assigned to degarelix and 11 (4.1%) patients assigned to leuprolide (hazard ratio, 1.28 [95% CI, 0.59-2.79]; P=0.53).

CONCLUSIONS

PRONOUNCE (A Trial Comparing Cardiovascular Safety of Degarelix Versus Leuprolide in Patients With Advanced Prostate Cancer and Cardiovascular Disease) is the first, international, randomized clinical trial to prospectively compare the cardiovascular safety of a GnRH antagonist and a GnRH agonist in patients with prostate cancer. The study was terminated prematurely because of the smaller than planned number of participants and events, and no difference in major adverse cardiovascular events at 1 year between patients assigned to degarelix or leuprolide was observed. The relative cardiovascular safety of GnRH antagonists and agonists remains unresolved. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02663908.

Risk of cardiovascular intervention after androgen deprivation therapy in prostate cancer patients with a prior history of ischemic cardiovascular and cerebrovascular disease: A nationwide population-based cohort study

BACKGROUND

Androgen deprivation therapy for prostate cancer is known to increase the risk of cardiovascular disease, but there is controversy regarding the cardiovascular risk in patients with preexisting cardiovascular disease. This study assessed the risk of cardiovascular intervention after androgen deprivation therapy in patients with a history of cardiovascular disease, cerebrovascular disease, and cardiovascular intervention.

MATERIALS AND METHODS

Between 2008 and 2017, 195,308 men with newly diagnosed prostate cancer were identified from the nationwide claims database in South Korea. Among them, 49,090 men with a history of ischemic cardiovascular and cerebrovascular diseases were analyzed. The patients were divided into the androgen deprivation therapy (n = 14,092) and non-androgen deprivation therapy (n = 34,988) groups. The primary outcome was cardiovascular interventions (percutaneous transluminal angioplasty and coronary bypass surgery). Cox proportional hazard regression models were used to estimate the adjusted hazard ratios and 95% confidence intervals of the events.

RESULTS

After balancing the covariates with 1:1 exact matching, the two groups had 10,514 subjects each. Multivariable analysis demonstrated that androgen deprivation therapy was not significantly associated with an increased risk of cardiovascular interventions (hazard ratio, 1.060; 95% confidence interval, 0.923-1.217; P = 0.4104), regardless of the duration of therapy. A history of cardiovascular intervention, diabetes mellitus, antithrombotic medication use, and cardiovascular events significantly increased the risk of cardiovascular intervention.

CONCLUSIONS

Androgen deprivation therapy was not associated with cardiovascular intervention in patients with a previous history of cardiovascular disease, regardless of the duration of therapy. Therefore, the cardiovascular risk of androgen deprivation therapy should be reassessed in this population.

Risk of cardiovascular mortality with androgen deprivation therapy in prostate cancer: A secondary analysis of the Prostate, Lung, Colorectal, and Ovarian (PLCO) Randomized Controlled Trial

BACKGROUND

For men with radiation-managed prostate cancer, there is conflicting evidence regarding the association between androgen deprivation therapy (ADT) and cardiovascular mortality (CVM), particularly among those who have with preexisting comorbidities. The objective of this study was to analyze the association between ADT and CVM across patient comorbidity status using prospectively collected data from a large clinical trial.

METHODS

In total, 1463 men were identified who were diagnosed with clinically localized, intermediate-risk/high-risk prostate cancer (T2b-T4, Gleason 7-10, or prostate-specific antigen >10 ng/mL) from 1993 to 2001 and managed with either radiation therapy (RT) alone or RT plus ADT during the randomized Prostate, Lung, Colon, and Ovarian (PLCO) Cancer Screening Trial. Adjusted hazard ratios (aHRs) for cause-specific mortality (prostate cancer-specific mortality vs other-cause mortality-including the primary end point of CVM [death from ischemic heart disease, cerebrovascular accident, or other circulatory disease]) were determined using Fine and Gray competing-risk regression analysis and stratified by comorbidity history.

RESULTS

There was no difference in the risk of 5-year CVM between ADT plus RT and RT alone (2.3% vs 3.3%, respectively; aHR, 0.69; 95% CI, 0.38-1.24; P = .21) overall or on subgroup analysis among men with a history of ≥1 preexisting comorbidities (3.2% vs 5.3%, respectively; aHR, 0.83; 95% CI, 0.43-1.60; P = .58), ≥2 preexisting comorbidities (6.9% vs 8.3%, respectively; aHR, 0.95; 95% CI, 0.40-2.25; P = .90), or cardiovascular disease/risk factors (3.6% vs 4.3%, respectively; aHR, 0.85; 95% CI, 0.44-1.65; P = .63). These results were all similar when each component of CVM was analyzed separately-either cardiac, stroke, or other vascular mortality (P > .05).

CONCLUSIONS

This study provides prospectively collected evidence that the use of ADT plus RT, compared with RT alone, is not associated with an increased risk of CVM, even among subgroups of men who have preexisting comorbidities and cardiovascular disease.

Impact of Hormonal Therapies for Treatment of Hormone-Dependent Cancers (Breast and Prostate) on the Cardiovascular System: Effects and Modifications: A Scientific Statement From the American Heart Association

Cardiovascular disease and cancer are the leading causes of death in the United States, and hormone-dependent cancers (breast and prostate cancer) are the most common noncutaneous malignancies in women and men, respectively. The hormonal (endocrine-related) therapies that serve as a backbone for treatment of both cancers improve survival but also increase cardiovascular morbidity and mortality among survivors. This consensus statement describes the risks associated with specific hormonal therapies used to treat breast and prostate cancer and provides an evidence-based approach to prevent and detect adverse cardiovascular outcomes. Areas of uncertainty are highlighted, including the cardiovascular effects of different durations of hormonal therapy, the cardiovascular risks associated with combinations of newer generations of more intensive hormonal treatments, and the specific cardiovascular risks that affect individuals of various races/ethnicities. Finally, there is an emphasis on the use of a multidisciplinary approach to the implementation of lifestyle and pharmacological strategies for management and risk reduction both during and after active treatment.

Does androgen-deprivation therapy increase the risk of ischemic cardiovascular and cerebrovascular diseases in patients with prostate cancer? A nationwide population-based cohort study

PURPOSE

We investigated whether ADT use was associated with the risk of ischemic cardiovascular diseases (CVD) and cerebrovascular diseases (CrVD) in a nationwide population-based cohort.

METHODS

Claims data of the Health Insurance and Review Assessment system in South Korea were used. In total, 195,308 men with newly diagnosed prostate cancer between January 1, 2008 and December 31, 2017 were identified. After applying the exclusion criteria, 131,189 men were enrolled. The study cohort was divided into ADT and non-ADT groups. Study outcomes were newly developed CVD, cardiovascular intervention (CVI), and CrVD. To control for potential confounders, various cardiovascular risk factors were balanced between groups. Cox proportional hazard regression models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of events.

RESULTS

Univariable analysis revealed that ADT was significantly associated with an increased risk of CVD and CrVD. Multivariable analysis did not reveal this association. In the propensity score matched cohort (n = 61,722), multivariable analysis demonstrated that ADT independently reduced the risk of CVD (HR 0.890; 95% CI 0.846-0.936; p < 0.0001), CVI (HR 0.873; 95% CI 0.770-0.991; p = 0.0352), and CrVD (HR 0.869; 95% CI 0.824-0.917; p < 0.0001). CVD risk was significantly decreased in patients using ADT for over 2 years. CVI and CrVD risks were significantly lower in men using ADT for over 3 years.

CONCLUSION

This study demonstrated that ADT may reduce the risk of CVD, CVI, and CrVD, and ADT duration is associated with this risk reduction.

Cardiovascular risks and toxicity - The Achilles heel of androgen deprivation therapy in prostate cancer patients

Androgen deprivation therapy (ADT) is the primary systemic therapy for treating locally advanced or metastatic prostate cancer (PCa). Despite its positive effect on PCa patient survival, ADT causes various adverse effects, including increased cardiovascular risk factors and cardiotoxicity. Lifespans extension, early use of ADT, and second-line treatment with next-generation androgen receptor pathway inhibitors would further extend the duration of ADT and possibly increase the risk of ADT-induced cardiotoxicity. Meanwhile, information on the molecular mechanisms underlying ADT-induced cardiotoxicity and measures to prevent it is limited, mainly due to the lack of specifically designed preclinical studies and clinical trials. This review article compiles up-to-date evidence obtained from observational studies and clinical trials, in order to gain new insights for deciphering the association between ADT use and cardiotoxicity. In addition, potential cardioprotective strategies involving GnRH receptors and second messenger cGMP are discussed.

Effects of castration on atherosclerosis in Yucatan minipigs with genetic hypercholesterolemia

Background

Low plasma testosterone, either spontaneous or as a result of androgen deprivation therapy for prostate cancer, is associated with an increased risk of cardiovascular events. The underlying mechanism in humans is not understood. Experimental studies in mice have shown that castration facilitates atherogenesis and may increase signs of plaque vulnerability. Pigs used for translational atherosclerosis research have frequently been castrated for practical or commercial reasons, but the effect of castration on atherosclerosis has never been systematically evaluated in pigs.

Objective

To study the effect of castration on atherosclerotic plaque burden and type in genetically modified minipigs with hypercholesterolemia.

Methods

Newborn male Yucatan minipigs with transgenic overexpression of a human gain-of-function mutant of proprotein convertase subtilisin/kexin type 9 were randomized to undergo orchiectomy (n = 8) or serve as controls (n = 6). Minipigs were started on high-fat diet at 3 months of age and the amount and composition of atherosclerotic lesions were analyzed at 12 months of age. Plasma lipid profiles and behavioral parameters were also assessed.

Results

Plasma lipids were slightly affected to a more atherogenic profile by orchiectomy, but atherosclerotic lesion size was unaltered in the LAD, thoracic aorta, abdominal aorta, and iliac arteries. The distribution of lesion types (xanthomas, pathological intimal thickening and fibroatheromas) were also not statistically different between groups in any of the examined vascular territories. The abdominal aorta developed the most advanced stages of disease with reproducible fibroatheroma formation, and here it was found that the area of necrotic core was significantly increased in orchiectomized pigs compared with controls. Orchiectomy also reduced aggressive behavior.

Conclusions

Castration does not alter the burden of atherosclerosis in hypercholesterolemic Yucatan minipigs, but may increase necrotic core area in fibroatheromas.

CYP17A1 deficient XY mice display susceptibility to atherosclerosis, altered lipidomic profile and atypical sex development

CYP17A1 is a cytochrome P450 enzyme with 17-alpha-hydroxylase and C17,20-lyase activities. CYP17A1 genetic variants are associated with coronary artery disease, myocardial infarction and visceral and subcutaneous fat distribution; however, the underlying pathological mechanisms remain unknown. We aimed to investigate the function of CYP17A1 and its impact on atherosclerosis in mice. At 4–6 months, CYP17A1-deficient mice were viable, with a KO:Het:WT ratio approximating the expected Mendelian ratio of 1:2:1. All Cyp17a1 knockout (KO) mice were phenotypically female; however, 58% were Y chromosome-positive, resembling the phenotype of human CYP17A1 deficiency, leading to 46,XY differences/disorders of sex development (DSD). Both male and female homozygous KO mice were infertile, due to abnormal genital organs. Plasma steroid analyses revealed a complete lack of testosterone in XY-KO mice and marked accumulation of progesterone in XX-KO mice. Elevated corticosterone levels were observed in both XY and XX KO mice. In addition, Cyp17a1 heterozygous mice were also backcrossed onto an Apoe KO atherogenic background and fed a western-type diet (WTD) to study the effects of CYP17A1 on atherosclerosis. Cyp17a1 x Apoe double KO XY mice developed more atherosclerotic lesions than Apoe KO male controls, regardless of diet (standard or WTD). Increased atherosclerosis in CYP17A1 XY KO mice lacking testosterone was associated with altered lipid profiles. In mice, CYP17A1 deficiency interferes with sex differentiation. Our data also demonstrate its key role in lipidomic profile, and as a risk factor in the pathogenesis of atherosclerosis.

Cardiovascular Risk Profile in Prostate Cancer Patients Treated with GnRH Agonists versus Antagonists: An Italian Real-World Analysis

Purpose

To evaluate and compare the incidence of cardiovascular (CV) events in a large contemporary cohort of patients diagnosed with prostate cancer (PCa) and in treatment with GnRH agonists or GnRH antagonists.

Patients and Methods

An Italian observational retrospective cohort study based on administrative databases of three local health units and two Regions was performed. PCa patients treated with GnRH agonists or antagonist were included between January 01, 2013 and December 31, 2016. Index date (ID) was the date of first GnRH agonist/antagonist prescription during inclusion period. Follow-up was from ID to December 31, 2017. Patients were excluded if they were under abiraterone treatment or combination therapy with antiandrogens during follow-up. The incidence rate of CV events (acute myocardial infarction, ischemic heart diseases, cerebrovascular diseases, cardiac dysrhythmias, heart failure, atherosclerosis, aneurism, other CV-related conditions) was calculated among patients not switching to androgen deprivation therapy (ADT) in the overall cohort and in a sub-cohort of patients without previous CV events.

Results

In total, 9785 (mean age 76.8 ± 8.5) patients were included: 9158 (93.6%) were treated with a GnRH agonist and 627 (6.4%) with a GnRH antagonist. Of them, 9627 did not switch to ADT and were considered in the analyses. The incidence of CV events was significantly higher in patients treated with GnRH agonists rather than antagonists (8.8 vs 6.2, p=0.002). Mean time to CV event was beyond 1 year of treatment in both groups. In the multivariable regression analysis, the risk of experiencing CV events was significantly lower in patients treated with GnRH antagonist rather than those treated with GnRH agonists [HR (95% CI): 0.76 (0.60-0.95), p=0.018]. These findings were confirmed in the sub-cohort of patients without previous CV events.

Conclusion

This Italian observational study shows that most patients received a GnRH agonist rather than a GnRH antagonist prescription. GnRH antagonist seems to have a better CV risk profile than GnRH agonist, both in patients with and without a history of CV events.

Nutrition care guidelines for men with prostate cancer undergoing androgen deprivation therapy: do we have enough evidence?

BACKGROUND

To review the evidence available to support clinical practice guidelines for dietary interventions aimed at mitigating the side effects of androgen deprivation therapy (ADT) in men with prostate cancer, and to identify future research priorities.

METHODS

An analytical model was designed to select and interpret evidence for the effect of dietary interventions on ADT side effects. Key terms identified articles that investigated dietary interventions to mitigate ADT side effects among men treated for prostate cancer. Medline, Embase, Proquest, CINAHL, Cochrane databases, and PubMed were searched from inception through June, 2018. Clinical trial registries were also searched for up-to-date study protocols. Articles were not restricted on design. Methodological quality was assessed using the mixed methods appraisal tool.

RESULTS

Sixteen articles met inclusion criteria, each with distinct dietary interventions. Twelve studies used interventions that combined diet with physical activity and/or medication and/or counselling. Four articles examined the effect of diet alone on ADT side effects. Of those, three articles measured changes to participants' dietary intake and influence on ADT side effects. One article showed daily caffeinated beverages improved cancer-related fatigue. Two articles showed no impact of isoflavone supplementation on hot flushes, quality of life, body mass index, or blood lipids. Dietary intake and compliance was poorly reported across all studies limiting knowledge of acceptability and feasibility for dietary interventions. Information on the nutrition care practices and views of clinicians treating men for prostate cancer is limited. No articles measured the impact of diet on long-term ADT side effects. Methodological quality of included papers ranged from weak to strong.

CONCLUSIONS

Current evidence for dietary interventions to mitigate ADT side effects is limited. Further investigations are warranted to explore the impact of changes in dietary intake on ADT side effects before practice guidelines can be considered.

Effects of a six-month supervised physical exercise program on physical and cardio-metabolic profile and quality of life in patients with prostate cancer on androgen deprivation therapy: a pilot and feasibility study

Introduction

To evaluate the effect of a six-month supervised physical exercise program on the physical and cardio-metabolic profile and quality of life in patients with prostate cancer on androgen deprivation therapy.

Material and methods

Twenty-seven patients with prostate cancer on androgen deprivation therapy were included in a physical exercise program. The program consisted of supervised physical exercises during a six-month period (two hours, twice a week). The exercise program contained moderate to high intensity aerobic and resistance exercises: cycling, walking or jogging for 45 minutes at an intensity of ±80% of the individual maximum heart rate, followed by resistance exercises targeting the major lower and upper body muscles. All patients were assessed prior to the exercise program, including anthropometrical parameters, blood analysis, quality of life and physical fitness. Blood analysis was repeated at a three-month follow-up. Anthropometrical parameters, physical fitness and quality of life were recorded at a three-, six- and nine-month follow-up.

Results

A positive effect on physical performance, muscular strength and quality of life was seen. The applied physical exercise program was well tolerated and characterized by a high satisfaction rate. An alarming issue of remarkably unfavorable baseline cardio-metabolic profile was revealed within our study population.

Conclusions

Our data indicates that a six-month supervised physical exercise program can be beneficial in preventing androgen deprivation therapy-related side effects in patients with prostate cancer. We emphasize the importance of screening for cardio-metabolic risk factors in patients who are treated with androgen deprivation therapy.

Testosterone Protects Against Atherosclerosis in Male Mice by Targeting Thymic Epithelial Cells-Brief Report

Supplemental Digital Content is available in the text.

Objective—

Androgen deprivation therapy has been associated with increased cardiovascular risk in men. Experimental studies support that testosterone protects against atherosclerosis, but the target cell remains unclear. T cells are important modulators of atherosclerosis, and deficiency of testosterone or its receptor, the AR (androgen receptor), induces a prominent increase in thymus size. Here, we tested the hypothesis that atherosclerosis induced by testosterone deficiency in male mice is T-cell dependent. Further, given the important role of the thymic epithelium for T-cell homeostasis and development, we hypothesized that depletion of the AR in thymic epithelial cells will result in increased atherosclerosis.

Approach and Results—

Prepubertal castration of male atherosclerosis-prone apoE^−/− mice increased atherosclerotic lesion area. Depletion of T cells using an anti-CD3 antibody abolished castration-induced atherogenesis, demonstrating a role of T cells. Male mice with depletion of the AR specifically in epithelial cells (E-ARKO [epithelial cell-specific AR knockout] mice) showed increased thymus weight, comparable with that of castrated mice. E-ARKO mice on an apoE^−/− background displayed significantly increased atherosclerosis and increased infiltration of T cells in the vascular adventitia, supporting a T-cell–driven mechanism. Consistent with a role of the thymus, E-ARKO apoE^−/− males subjected to prepubertal thymectomy showed no atherosclerosis phenotype.

Conclusions—

We show that atherogenesis induced by testosterone/AR deficiency is thymus- and T-cell dependent in male mice and that the thymic epithelial cell is a likely target cell for the antiatherogenic actions of testosterone. These insights may pave the way for new therapeutic strategies for safer endocrine treatment of prostate cancer.

Selective Androgen Receptor Modulator S42 Suppresses Prostate Cancer Cell Proliferation

We previously identified the selective androgen receptor (AR) modulator S42, which does not stimulate prostate growth but has a beneficial effect on lipid metabolism. In the prostate cancer (PC) cell line LNCaP, S42 did not induce AR transactivation but antagonized 5α-dihydrotestosterone (DHT)‒induced AR activation. Next, we investigated whether S42 suppresses the growth of PC cell lines. Basal growth of LNCaP cells was significantly suppressed by treatment with S42 compared with vehicle, as determined by cell counting and 5-bromo-2'-deoxyuridine assays. The suppressive effect of S42 on cell growth was evident in the AR-positive PC cells LNCaP and 22Rv1 and was slightly observed even in the AR-negative PC-3 cells. However, S42 did not induce apoptosis as determined by the terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling assay. S42 had an even greater suppressive effect on DHT-dependent LNCaP cell proliferation than on basal proliferation (P < 0.05). DHT treatment increased the expression of phosphorylated extracellular signal-regulated kinase (ERK)-mitogen-activated protein kinase (MAPK), a major signaling molecule for PC proliferation, and this was significantly inhibited by S42. DHT also significantly upregulated AR, insulinlike growth factor-1 receptor (IGF-1R), and insulin receptor (IR)-β protein levels, which were similarly reduced by S42 treatment. Importantly, S42 administration to mice attenuated the growth of LNCaP tumors and reduced tumor expression of the prostate-specific antigen, P504S, Ki67, and phosphorylated ERK-MAPK. These data suggest that S42 attenuates LNCaP tumor growth not by inducing apoptosis but by inhibiting the expression of proliferation-related receptors, including IGF-1R, IR, and AR, and by suppressing ERK-MAPK activation. S42 may thus be a feasible candidate for PC treatment.

Risks of Serious Toxicities from Intermittent versus Continuous Androgen Deprivation Therapy for Advanced Prostate Cancer: A Population Based Study

PURPOSE

Randomized trials have shown that intermittent androgen deprivation therapy for patients with advanced prostate cancer may improve sexual and physical functioning compared to continuous androgen deprivation therapy without compromising survival. To our knowledge it is unknown whether intermittent androgen deprivation therapy alters the risk of serious toxicities associated with continuous androgen deprivation therapy.

MATERIALS AND METHODS

We performed a population based cohort study of 9,772 men 66 years old or older who were diagnosed with advanced prostate cancer from 2002 to 2011 and treated with androgen deprivation therapy. Intermittent androgen deprivation therapy was defined as a single 90-day interval between 2 androgen deprivation therapy sessions during which patients visited their physicians or underwent prostate specific antigen testing. Outcomes included acute myocardial infarction, stroke, heart failure, type 2 diabetes and fracture. We used Cox proportional hazard models to estimate the HRs of the comparative risk of serious toxicities between intermittent and continuous androgen deprivation therapy.

RESULTS

A total of 2,113 (22%), 769 (9%) and 899 men (9%) had a new cardiovascular event, diabetes or fracture, respectively, within 5 years of starting androgen deprivation therapy. Compared to the continuous androgen deprivation therapy group, the intermittent therapy group was at lower risk for serious cardiovascular events (HR 0.64, 95% CI 0.53-0.77), particularly in reducing the risk of heart failure (HR 0.62, 95% CI 0.49-0.78) and fracture (HR 0.52, 95% CI 0.38-0.70, each p <0.0001).

CONCLUSIONS

Intermittent androgen deprivation therapy was associated with a lower risk of heart failure and fracture compared to continuous androgen deprivation therapy. This raises toxicity concerns for continuous relative to intermittent therapy and suggests that intermittent androgen deprivation therapy may represent a safer therapeutic choice in elderly men with advanced prostate cancer.

The potential role of follicle-stimulating hormone in the cardiovascular, metabolic, skeletal, and cognitive effects associated with androgen deprivation therapy

PURPOSE

To explore how follicle-stimulating hormone (FSH) may contribute to cardiovascular, metabolic, skeletal, and cognitive events in men treated for prostate cancer, with various forms of androgen deprivation therapy (ADT).

MATERIALS AND METHODS

A colloquium of prostate cancer experts was convened in May 2015, to discuss the role of FSH in the development of unwanted effects associated with ADT. Subsequently, a literature review (Medline, PubMed, and relevant congress abstract databases) was performed to further explore and evaluate the collected evidence.

RESULTS

It has become evident that, in the setting of ADT, FSH can promote the development of atherosclerotic plaque formation, metabolic syndrome, and insulin resistance. Data also suggest that FSH is an important mediator of bone remodeling, particularly bone resorption, and thereby increases the risk for bone fracture. Additional evidence implicates a role for FSH in bone metastasis as well. The influence of FSH on ADT-induced cognitive deficits awaits further elucidation; however, the possibility that FSH may be involved therein cannot be ruled out.

CONCLUSIONS

The widespread molecular and physiological consequences of FSH system activation in normal and pathological conditions are becoming better understood. Progress in this area has been achieved by the development of additional investigative and clinical measures to better evaluate specific adverse effects. More research is needed on FSH function in the development of cancer as well as its association with cardiovascular, metabolic, musculoskeletal, and cognitive effects in ADT.

Effects of androgen-deprivation therapy on hypercoagulability in prostate cancer patients: A prospective, longitudinal study

INTRODUCTION

Androgen-deprivation therapy (ADT) is the mainstay of systemic therapy for advanced prostate cancer (PCa), but has significant adverse effects, including increasing concern for cardiovascular (CV) and thromboembolic (TE) complications. This study carefully investigates any relationship between ADT use and hypercoagulability as a possible mechanism of these adverse effects.

METHODS

We performed a prospective, longitudinal study in a cohort of patients with advanced PCa initiating ADT (n=18). Controls included men with biochemical failure after local therapy on watchful waiting (n=10), as well as healthy controls (n=8). Global hemostasis was evaluated using the sensitive global hemostasis assay, thromboelastography (TEG). Patients were evaluated at baseline and every three months for a minimum of 12 months.

RESULTS

The results of the TEG studies demonstrated 14/18 (78%) of advanced PCa patients had evidence of a hypercoagulable state before initiating therapy. Significant baseline hypercoagulability was documented in this cohort compared to the two control groups. ADT did not appear to exacerbate hypercoagulability over time as a whole: only 10/18 (56%) patients had TEG findings consistent with hypercoagulability at the end of study. However, 3/18 (17%) PCa patients initiating ADT had significantly new hypercoagulable TEG changes on treatment compared to baseline.

CONCLUSIONS

This prospective pilot study demonstrates a complex interaction between ADT and hypercoagulable state in men with advanced PCa. TEG abnormalities were mostly associated with volume of cancer as compared to ADT use; however, it is possible that ADT may lead to hypercoagulability in a subset of men, suggesting that sensitive monitoring of coagulation of men on ADT could help identify those at risk of developing CV/TE complications. Study limitations include the relatively small cohort of men followed after initiating ADT and these results require confirmation in a larger trial to rule out subtle effects on hypercoagulability.

[Cardiovascular risk of androgen deprivation therapy for treatment of hormone-dependent prostate cancer : Differences between GnRH antagonists and GnRH agonists]

BACKGROUND

Several studies have indicated that reduction of testosterone levels in patients with prostate cancer undergoing androgen deprivation therapy (ADT) with gonadotropin-releasing hormone (GnRH) agonists can be associated with an increased risk of cardiovascular events. The GnRH antagonists have a different mode of action compared with GnRH agonists and may be preferred in ADT for patients with cardiovascular disease.

OBJECTIVE

This review article discusses potential mechanisms underlying the development of cardiovascular events associated with ADT when using GnRH agonists and explains the differences in mode of action between GnRH agonists and GnRH antagonists. Additionally, relevant studies are presented and practical recommendations for the clinical practice are provided.

MATERIAL AND METHODS

A literature search was performed. Full publications and abstracts published in the last 10 years up to September 2015 were considered to be eligible.

RESULTS

The GnRH antagonists were associated with a decreased risk of cardiovascular events compared with GnRH agonists in prostate cancer patients undergoing ADT and particularly in patients with cardiovascular risk factors or a history of cardiovascular disease. This decrease may be due to the different mode of action of GnRH antagonists compared with GnRH agonists.

CONCLUSION

Prostate cancer patients with either cardiovascular disease or an increased risk of experiencing a cardiovascular event undergoing ADT should be preferentially treated with GnRH antagonists.

Binding site of activators of the cystic fibrosis transmembrane conductance regulator in the nucleotide binding domains

The use of substances that could activate the defective chloride channels of the mutant cystic fibrosis transmembrane conductance regulator (CFTR) has been suggested as possible therapy for cystic fibrosis. Using epithelia formed by cells stably transfected with wildtype or mutant (G551D, G1349D) CFTR, we estimated the apparent dissociation constant, K(D), of a series of CFTR activators by measuring the increase in the apical membrane current. Modification of apparent K(D) of CFTR activators by mutations of the nucleotide-binding domains (NBDs) suggests that the binding site might be in these regions. The human NBD structure was predicted by homology with murine NBD1. An NBD1-NBD2 complex was constructed by overlying monomers to a bacterial ABC transporter NBD dimer in the "head-to-tail" conformation. Binding sites for CFTR activators were predicted by molecular docking. Comparison of theoretical binding free energy estimated in the model to free energy estimated from the apparent dissociation constants, K(D), resulted in a remarkably good correlation coefficient for one of the putative binding sites, located in the interface between NBD1 and NBD2.