Antiandrogen treatments in locally advanced prostate cancer: are they all the same?

Novel insights into post-marketing AEs associated with leuprorelin: A comprehensive analysis utilizing the FAERS database

Purpose

This research focused on meticulously tracking and identifying adverse reactions associated with leuprorelin, a drug prescribed for conditions such as prostate cancer, endometriosis, uterine fibroids, and early-onset puberty. The main objective was to enhance patient safety and offer informed guidance on the appropriate use of this treatment.

Methods

From the first quarter of 2004 to the fourth quarter of 2023, a comprehensive analysis was conducted on a significant number of adverse event reports (AERs) from the FDA Adverse Event Reporting System (FAERS) database. Data mining with dismutation analysis was conducted to quantify signals associated with adverse events (AEs) related to leuprorelin, utilizing powerful algorithms such as ROR, PRR, BCPNN, and EBGM.

Results

A total of 102 positive reaction terms (PT) spanning 24 System Organ Classes (SOCs) were identified from an analysis of 60,709 reports associated with leuprorelin use. Notably, several previously unrecognized adverse reactions were uncovered, including Artificial Menopause, Ovarian Adhesion, Follicular Cystitis, Intercepted product preparation error, among others. These findings underscore the importance of exercising additional vigilance regarding the potential adverse effects of leuprorelin, such as Abscess Sterile, Injection site granuloma, Intercepted medication error, and Bulbospinal muscular atrophy congenital.

Conclusions

This research has successfully uncovered new and unforeseen signals associated with adverse drug reactions (ADRs) following leuprorelin administration. The study provides valuable insights into the intricate connection between ADRs and leuprorelin usage. The results underscore the crucial significance of continuous surveillance and meticulous monitoring to promptly identify and manage AEs, ultimately enhancing patient safety and well-being while undergoing leuprorelin therapy.

How to Improve the Quality of Life of Patients with Prostate Cancer Treated with Hormone Therapy?

Prostate cancer (PC) is a hormone-sensitive tumor. Androgen deprivation therapy (ADT) is the cornerstone of systemic therapy for patients with intermediate or high-risk localized, recurrent, and metastatic prostate cancer. Although generally well tolerated, ADT can lead to short- and long-term adverse events that can worsen the quality of life of patients with PC. In the last decade, the introduction of novel generation androgen receptor pathway inhibitors (ARPI) has resulted in an improvement in the prognosis of patients with metastatic PC when used in combination with ADT. The use of ARPI in increasingly early stages of the disease determines a longer exposure of patients to these treatments. Although ARPIs are normally well-tolerated drugs, they generally cause an increase in toxicity compared to ADT alone, being able to worsen some adverse events already induced by ADT or leading to the development of specific side effects. Although there are no specific treatments for all the adverse events induced by hormonal therapies, it is essential to know the possible toxicities induced by the different treatments and to start procedures to prevent and/or recognize and consequently treat them early in order to not compromise the quality of life of the patients with PC. The aim of this review is to describe the adverse events induced by hormonal therapies. We will first describe the side effects induced by both ADT and ARPI and then the specific adverse events of the different ARPIs. Furthermore, we will try to highlight the possible therapeutic options to prevent or mitigate the toxicity induced by hormone therapies in order to improve the quality of life of the patients with PC.

Exploring anti-androgen therapies in hormone dependent prostate cancer and new therapeutic routes for castration resistant prostate cancer

Androgen deprivation therapies (ADTs) are important treatments which inhibit androgen-induced prostate cancer (PCa) progression by either preventing androgen biosynthesis (e.g. abiraterone) or by antagonizing androgen receptor (AR) function (e.g. bicalutamide, enzalutamide, darolutamide). A major limitation of current ADTs is they often remain effective for limited durations after which patients commonly progress to a lethal and incurable form of PCa, called castration-resistant prostate cancer (CRPC) where the AR continues to orchestrate pro-oncogenic signalling. Indeed, the increasing numbers of ADT-related treatment-emergent neuroendocrine-like prostate cancers (NePC), which lack AR and are thus insensitive to ADT, represents a major therapeutic challenge. There is therefore an urgent need to better understand the mechanisms of AR action in hormone dependent disease and the progression to CRPC, to enable the development of new approaches to prevent, reverse or delay ADT-resistance. Interestingly the AR regulates distinct transcriptional networks in hormone dependent and CRPC, and this appears to be related to the aberrant function of key AR-epigenetic coregulator enzymes including the lysine demethylase 1 (LSD1/KDM1A). In this review we summarize the current best status of anti-androgen clinical trials, the potential for novel combination therapies and we explore recent advances in the development of novel epigenetic targeted therapies that may be relevant to prevent or reverse disease progression in patients with advanced CRPC.

Second brazilian consensus on the treatment of advanced prostate cancer - a SBOC-SBU-SBRT panel review

Prostate cancer is the second most common cancer and the fifth leading cause of cancer deaths. In Brazil, it is likewise the second most common cancer among men, second only to non-melanoma skin cancers.

The aim of this consensus is to align different opinions and interpretations of the medical literature in a practical and patient-oriented approach. The first Brazilian Consensus on the Treatment of Advanced Prostate Cancer was published in 2017, with the goal of reducing the heterogeneity of therapeutic conduct in Brazilian patients with metastatic prostate cancer. We acknowledge that in Brazil the incorporation of different technologies is a big challenge, especially in the Sistema Único de Saúde (SUS), which allows for the disparity in the options available to patients treated in different institutions. In order to update the recommendations and to make them objective and easily accessible, once more a panel of specialists was formed in order to discuss and elaborate a new Brazilian Consensus on Advanced Prostate Cancer. This Consensus was written through a joint initiative of the Brazilian Society of Clinical Oncology (SBOC) and the Brazilian Society of Urology (SBU) to support the clinical decisions of physicians and other health professionals involved in the care of patients with prostate cancer.

The drugs that mostly frequently induce gynecomastia: A national case - noncase study

AIMS

Drug-induced gynecomastia accounts for up to 25% of cases of gynecomastia. The objective of the present study was to provide a comprehensive overview of drug-induced gynecomastia on the basis of spontaneously reported adverse drug reactions (ADRs) in the French national pharmacovigilance database (FPVD).

METHODS

We performed a case - noncase study of drug-induced gynecomastia. Cases corresponded to reports of gynecomastia recorded in the FPVD between 1 January 2008 and 31 December 2015. The noncases corresponded to all other spontaneously reported ADRs recorded in the FPVD during the same period. Data were expressed as the reporting odds ratio (ROR) and its 95% confidence interval.

RESULTS

Of the 255,354 ADRs recorded in the FPVD between 1 January 2008 and 31 December 2015, 327 (0.31%) of relevant cases of gynecomastia and 106,800 noncases were analyzed. The RORs were statistically significant for 54 active compounds mentioned 429 times in cases of gynecomastia. A single drug was involved in 59% of cases. The most frequently implicated drug classes were antiretrovirals (23.5%), diuretics (15.5%), proton pump inhibitors (11.9%), HMG-CoA reductase inhibitors (9.1%), neuroleptics and related drugs (6.5%), calcium channel blockers (6.3%), and 5-alpha reductase inhibitors (4%).

CONCLUSIONS

A comprehensive analysis of a national pharmacovigilance database highlighted the main drug classes suspected of inducing gynecomastia. A physiopathological mechanism (a hormone imbalance with elevated estrogen levels) is known or suspected for most of the drugs involved in gynecomastia. However, we noticed a lack of harmonization in the summary of product characteristics for original vs. generic medicines.

Structural Based Screening of Antiandrogen Targeting Activation Function-2 Binding Site

Androgen receptor (AR) plays a critical role in the development and progression of prostate cancer (PCa). Current antiandrogen therapies induce resistant mutations at the hormone binding pocket (HBP) that convert the activity of these agents from antagonist to agonist. Thus, there is a high unmet medical need for the development of novel antiandrogens which circumvent mutation-based resistance. Herein, through the analysis of AR structures with ligands binding to the activation function-2 (AF2) site, we built a combined pharmacophore model. In silico screening and the subsequent biological evaluation lead to the discovery of the novel lead compound IMB-A6 that binds to the AF2 site, which inhibits the activity of either wild-type (WT) or resistance mutated ARs. Our work demonstrates structure-based drug design is an efficient strategy to discover new antiandrogens, and provides a new class of small molecular antiandrogens for the development of novel treatment agents against PCa.

Combined oral contraceptives promote androgen receptor and oestrogen receptor alpha upregulation in the female prostate (Skene’s paraurethral glands) of adult gerbils (Meriones unguiculatus)

The aim of this study was to evaluate the effects of cyproterone acetate (CPA) and ethinyloestradiol (EE) alone or in combination on the female prostate of adult gerbils. Adult females were exposed for 21 days to daily oral doses of CPA (1 mg kg−1), EE (10 µg kg−1) or a combination of CPA and EE. Female prostatic complexes were removed, weighed and subjected to morphological, stereological, immunohistochemical and ultrastructural analyses. CPA treatment caused epithelial atrophy and decreased prostate secretory activity. The EE treatment group showed glandular hyperplasia, a high cell-proliferation index and an increase in androgen and oestrogen receptor α (AR and ERα) immunoreactivity. Combined treatment (CPA+EE) caused adverse effects, such as an increase in cell proliferation, higher AR and ERα immunoreactivity, prostatic intraepithelial neoplasia, cell degeneration and aging. In conclusion, the CPA-only treatment promoted antiandrogenic effects on the female gerbil prostate, whereas EE-only had a potent oestrogenic activity. However, when combined, EE overlapped the effects of CPA, changing the pattern of glandular hormonal regulation and stimulating the development of prostatic lesions in female gerbils.

Specificity of anti-prostate cancer CYP17A1 inhibitors on androgen biosynthesis

The orteronel, abiraterone and galeterone, which were developed to treat castration resistant prostate cancer, inhibit 17,20 lyase activity but little is known about their effects on adrenal androgen biosynthesis. We studied the effect of several inhibitors and found that orteronel was selective towards 17,20 lyase activity than abiraterone and galeterone. Gene expression analysis showed that galeterone altered the expression of HSD3B2 but orteronel did not change the expression of HSD3B2, CYP17A1 and AKR1C3. The CYP19A1 activity was not inhibited except by compound IV which lowered activity by 23%. Surprisingly abiraterone caused complete blockade of CYP21A2 activity. Analysis of steroid metabolome by gas chromatography - mass spectrometry revealed changes in steroid levels caused by different inhibitors. We can conclude that orteronel is a highly specific inhibitor of 17,20 lyase activity. The discovery of these specific drug actions on steroidogenic enzyme activities would be valuable for understanding the regulation of androgens.

Progress in antiandrogen design targeting hormone binding pocket to circumvent mutation based resistance

Androgen receptor (AR) plays a critical role in the development and progression of prostate cancer (PCa). Current clinically used antiandrogens such as flutamide, bicalutamide, and newly approved enzalutamide mainly target the hormone binding pocket (HBP) of AR. However, over time, drug resistance invariably develops and switches these antiandrogens from antagonist to agonist of the AR. Accumulated evidence indicates that AR mutation is an important cause for the drug resistance. This review will give an overview of the mutation based resistance of the current clinically used antiandrogens and the rational drug design to overcome the resistance, provides a promising strategy for the development of the new generation of antiandrogens targeting HBP.

Safety of antiandrogen therapy for treating prostate cancer

INTRODUCTION

Antiandrogens are a treatment option in patients with prostate cancer, given either in combination with androgen deprivation or, in selected cases, as monotherapy. New-generation antiandrogens have been recently introduced in clinical practice (enzalutamide) or are under evaluation in clinical trials (ARN-509).

AREAS COVERED

This review elucidates the safety profile of antiandrogens, in particular focusing on the tolerability profile of each drug either when employed in combination with castration or as monotherapy, in hormone-naive or in castration-resistant patients.

EXPERT OPINION

Non-steroidal antiandrogens are widely used in the management of hormone-sensitive disease in combination with luteinizing hormone-releasing hormone agonists or in patients failing front-line treatment with androgen-deprivative maneuvers. In selected patients, non-steroidal antiandrogen monotherapy appears to yield comparable results as castration. Novel non-steroidal antiandrogens have been investigated with promising results in castration-resistant prostate cancer. Beyond the safety profile specific to any individual compound, increased testosterone and 17β-estradiol levels are commonly observed during antiandrogen monotherapy, leading to gynecomastia and breast pain. The safety profile of old and novel antiandrogens should be taken into account by clinicians in decision making and in selecting the most suitable patients. Beyond patient selection, full clinical evaluation of patient co-morbidities that might affect the drug tolerability and clinical monitoring are anyway required.

[Hormonal treatment in prostate cancer]

AIM

To describe drugs used in the hormonal treatment (hormonotherapy) of prostate cancer.

MATERIAL

Bibliographical search was performed from the database Medline (National Library of Medicine, PubMed) and websites of the HAS and the ANSM. The search was focused on the characteristics, the mode of action, the efficiency and the side effects of the various drugs concerned.

RESULTS

LHRH analogs and the antiandrogens remain the cornerstone in the treatment of locally advanced and metastatic prostate cancer. New therapeutic classes emerged recently (inhibitor of the synthesis of the androgen, the new antiandrogens) and allowed to grow again the limits of the hormone resistance and define the concept castration-resistant prostate cancer.

CONCLUSION

The hormonal treatment of the prostate cancer grew rich of new therapeutic classes which are going to change the medical care of the prostate cancer in the coming years and the urologist must play its full part.

A partial differential equation model of metastasized prostatic cancer

Biochemically failing metastatic prostate cancer is typically treated with androgen ablation. However, due to the emergence of castration-resistant cells that can survive in low androgen concentrations, such therapy eventually fails. Here, we develop a partial differential equation model of the growth and response to treatment of prostate cancer that has metastasized to the bone. Existence and uniqueness results are derived for the resulting free boundary problem. In particular, existence and uniqueness of solutions for all time are proven for the radially symmetric case. Finally, numerical simulations of a tumor growing in 2-dimensions with radial symmetry are carried in order to evaluate the therapeutic potential of different treatment strategies. These simulations are able to reproduce a variety of clinically observed responses to treatment, and suggest treatment strategies that may result in tumor remission, underscoring our model's potential to make a significant contribution in the field of prostate cancer therapeutics.

Drug-induced gynecomastia

Drugs account for about 20% of gynecomastia cases in men. As a number of factors can alter the estrogen:androgen ratio, several pathophysiologic mechanisms are associated with drugs causing this disorder. Antiandrogens, protease inhibitors, and nucleoside reverse transcriptase inhibitors are the most common drug causes of gynecomastia, whereas first-generation antipsychotics, spironolactone, verapamil, and cimetidine are less common causes. Other drugs have been reported rarely as causes. Treatment may involve switching to an alternative agent or may require surgery or irradiation if the causative agent cannot be discontinued. We reviewed the literature on drug-induced gynecomastia and provided another perspective by reviewing data from the United States Food and Drug Administration's Adverse Event Reporting System. Epidemiologic studies are needed to provide a more accurate description of the frequency of drug-induced gynecomastia.

Role of dutasteride in pre-clinical ETS fusion-positive prostate cancer models

BACKGROUND

Androgens play a crucial role in prostate cancer, hence the androgenic pathway has become an important target of therapeutic intervention. Previously we discovered that gene fusions between the 5'-untranslated region of androgen regulated gene TMPRSS2 and the ETS transcription factor family members were present in a majority of the prostate cancer cases. The resulting aberrant overexpression of ETS genes drives tumor progression.

METHODS

Here, we evaluated the expression levels of 5α-reductase isoenzymes in prostate cancer cell lines and tissues. We tested the effect of dutasteride, a 5α-reductase inhibitor, in TMPRSS2-ERG fusion-positive VCaP cell proliferation and cell invasion. We also evaluated the effect of dutasteride on the TMPRSS2-ERG fusion gene expression. Finally, we tested dutasteride alone or in combination with an anti-androgen in VCaP cell xenografts tumor model.

RESULTS

Our data showed that 5α-reductase SRD5A1 and SRD5A3 isoenzymes that are responsible for the conversion of testosterone to DHT, are highly expressed in metastatic prostate cancer compared to benign and localized prostate cancer. Dutasteride treatment attenuated VCaP cell proliferation and invasion. VCaP cells pre-treated with dutasteride showed a reduction in ERG and PSA expression. In vivo studies demonstrated that dutasteride in combination with the anti-androgen bicalutamide significantly decreased tumor burden in VCaP cell xenograft model.

CONCLUSIONS

Our findings suggest that dutasteride can inhibit ERG fusion-positive cell growth and in combination with anti-androgen, significantly reduce the tumor burden. Our study suggests that anti-androgens used in combination with dutasteride could synergistically augment the therapeutic efficacy in the treatment of ETS-positive prostate cancer.

New insights into the androgen-targeted therapies and epigenetic therapies in prostate cancer

Prostate cancer is the most common cancer in men in the United States, and it is the second leading cause of cancer-related death in American men. The androgen receptor (AR), a receptor of nuclear family and a transcription factor, is the most important target in this disease. While most efforts in the clinic are currently directed at lowering levels of androgens that activate AR, resistance to androgen deprivation eventually develops. Most prostate cancer deaths are attributable to this castration-resistant form of prostate cancer (CRPC). Recent work has shed light on the importance of epigenetic events including facilitation of AR signaling by histone-modifying enzymes, posttranslational modifications of AR such as sumoylation. Herein, we provide an overview of the structure of human AR and its key structural domains that can be used as targets to develop novel antiandrogens. We also summarize recent findings about the antiandrogens and the epigenetic factors that modulate the action of AR.

Novel, potent anti-androgens of therapeutic potential: recent advances and promising developments

The beneficial effect of androgen ablation has been well established in prostate cancer therapy. Despite the initial response, patients typically relapse with a more aggressive form described as castration-resistant prostate cancer (CRCP), driven by continued androgen receptor (AR) signaling. This review details the current state of anti-androgen therapy, mainly for CRPC, with major emphasis on the most potent and promising compounds under development. Anti-androgen failure has been linked to elevated AR expression, increased expression of coactivator proteins, AR mutations, ligand-independent AR activation and persistent intraprostatic androgens. MDV3100, BMS-641988 and VN/124-1 were developed to overcome these mechanisms. In CRCP, prostate cancer cells still rely on intracellular androgens and, to a greater extent, on active AR for growth and survival. Therefore, potent anti-androgens that efficiently disrupt the functions (signaling) of AR are envisioned to be effective drugs for all types of prostate cancers.

Androgen receptor-dependent and independent atheroprotection by testosterone in male mice

The atheroprotective effect of testosterone is thought to require aromatization of testosterone to estradiol, but no study has adequately addressed the role of the androgen receptor (AR), the major pathway for the physiological effects of testosterone. We used AR knockout (ARKO) mice on apolipoprotein E-deficient background to study the role of the AR in testosterone atheroprotection in male mice. Because ARKO mice are testosterone deficient, we sham operated or orchiectomized (Orx) the mice before puberty, and Orx mice were supplemented with placebo or a physiological testosterone dose. From 8 to 16 wk of age, the mice consumed a high-fat diet. In the aortic root, ARKO mice showed increased atherosclerotic lesion area (+80%, P < 0.05). Compared with placebo, testosterone reduced lesion area both in Orx wild-type (WT) mice (by 50%, P < 0.001) and ARKO mice (by 24%, P < 0.05). However, lesion area was larger in testosterone-supplemented ARKO compared with testosterone-supplemented WT mice (+57%, P < 0.05). In WT mice, testosterone reduced the presence of a necrotic core in the plaque (80% among placebo-treated vs. 12% among testosterone-treated mice; P < 0.05), whereas there was no significant effect in ARKO mice (P = 0.20). In conclusion, ARKO mice on apolipoprotein E-deficient background display accelerated atherosclerosis. Testosterone treatment reduced atherosclerosis in both WT and ARKO mice. However, the effect on lesion area and complexity was more pronounced in WT than in ARKO mice, and lesion area was larger in ARKO mice even after testosterone supplementation. These results are consistent with an AR-dependent as well as an AR-independent component of testosterone atheroprotection in male mice.

Preliminary study with bicalutamide in heterosexual and homosexual patients with prostate cancer: a possible implication of androgens in male homosexual arousal

OBJECTIVE

• Not only has a precise characterization of libido and sexual arousal in men as a central neural process been lacking, but the interactive role of gonadal hormones and sexual orientation in such processes has never been investigated. We investigate the relationships among sexual hormones, sexual arousal, and sexual orientation in men by comparing the self-reported sexual response of heterosexual and homosexual men with locally advanced prostate neoplasm, receiving the non-steroidal anti-androgen bicalutamide as monotherapy.

PATIENTS AND METHODS

• 29 Romanian men participated in this study: 17 heterosexual and 12 homosexual. Patients were undergoing treatment for prostate cancer consisting of a standard daily dose of 50 mg bicalutamide, a fast acting non-steroidal anti-androgen with action comparable to other anti-androgen drugs but with reportedly fewer sexual side effects. • Patients retrospectively provided information regarding their sexual functioning measured by the IIEF prior to commencing bicalutamide treatment. • Then, about five weeks later, patients were asked to prospectively provide information regarding their current sexual functioning while undergoing bicalutamide treatment.

RESULTS

• Overall IIEF scores as well as the Erectile Function, Orgasmic Function, Sexual Desire, and Overall Satisfaction subscales showed group, treatment, and group by treatment effects. • The Intercourse Satisfaction subscale showed group and group by treatment effects. • On most subscales, homosexual men showed lower functioning than heterosexual men, primarily in response to treatment with bicalutamide.

CONCLUSIONS

• Treatment with an anti-androgen in a clinical population of men undergoing therapy for prostate cancer affected homosexual men more than heterosexual men, although not all heterosexual men were unaffected. • These results are discussed in the context of dual sexual natures, a concept recently developed in the sexual literature. • Furthermore, these findings reiterate the importance of incorporating such variables as sexual orientation into studies investigating medical treatments on sexual response.

Estrogen receptor beta selective nonsteroidal estrogens: seeking clinical indications

IMPORTANCE OF THE FIELD

Nonsteroidal estrogens have been known since the 1930s. However, the relatively recent (1996) discovery of estrogen receptor subtype beta (ERbeta) suggested a possible paradigm shift away from SERM-like selectivity. Selective ERbeta agonism would potentially allow expansion of estrogenic targeting into new indications (discussed herein) currently precluded by the thrombogenic and hyperproliferative effects of nonselective estrogens.

AREAS COVERED IN THIS REVIEW

ERbeta agonist design has been very successful. Pharmacophores for ERbeta selective nonsteroidal estrogens are generally diphenolic compounds that achieve an inter-phenolic distance and geometry similar to 17beta-estradiol with few restraints on the nature of the element linking the phenols (or phenol mimetics). The tremendously chemodiverse ERbeta agonist patent literature is reviewed, segregating the agonists into structurally similar compounds based on their interphenolic linking elements.

WHAT THE READER WILL GAIN

A comprehensive understanding of the chemotype landscape of this field and an assessment of its maturation.

TAKE HOME MESSAGE

Subtype selective ERbeta agonist therapy seems very promising. However, more clinical testing is needed to firmly establish its therapeutic potential. At this point, ERbeta is a promising target in search of an indication.

Coactivator selective regulation of androgen receptor activity

The androgen receptor (AR) is a ligand activated nuclear receptor, which regulates transcription and stimulates growth of androgen dependent prostate cancer. To regulate transcription, AR recruits a series of coactivators that modify chromatin and facilitate transcription. However, information on ligand and target gene-specific requirements for coactivators is limited. We compared the actions of the p160 coactivators SRC-1 and SRC-3/RAC3 with SRA (steroid receptor RNA activator). All three coactivate AR in the presence of agonist as expected. However, overexpression of either SRC-1 or SRC-3 increased AR activity in response to the partial antagonist, cyproterone acetate, whereas SRA was unable to stimulate AR activity under these conditions. Using siRNA to reduce expression of these coactivators in LNCaP cells, we also found promoter specific requirement for these coactivators. SRC-3 is required for optimal androgen dependent induction of PSA, TMPRSS2, and PMEPA1 whereas SRA is required only for optimal induction of the TMPRSS2 gene. These data indicate that different groups of AR target genes have distinct requirements for coactivators and response to AR ligands.

Cognitive and mood changes in men undergoing intermittent combined androgen blockade for non-metastatic prostate cancer

PURPOSE

Men with prostate-specific antigen (PSA)-only relapse of prostate cancer after primary therapy are generally fully functional and asymptomatic with a life expectancy of up to 10 or more years. Androgen deprivation therapy (ADT) is a common treatment option. This study examined mood and cognitive changes in otherwise healthy men with prostate cancer prior to, during and after ADT.

EXPERIMENTAL DESIGN

Twenty hormone naïve, eugonadal prostate cancer patients without evidence of metastases and with a rising PSA were treated with intermittent ADT consisting of 9 months of complete androgen blockade (CAB) achieved with combined leuprolide and flutamide followed by an 'off treatment' period. Cognitive function tests and mood measures were administered at baseline, after 3 and 9 months of ADT and after 3 months of no treatment. Twenty healthy control patients without prostate cancer range matched for age and education were tested at the same time intervals.

RESULTS

ADT patients evidenced a significant decline in spatial reasoning, spatial abilities and working memory during treatment compared with baseline. No changes were noted for measures of verbal or spatial memory, selective attention or language. Significant changes in self-rated mood such as increased depression, tension, anxiety, fatigue and irritability were evident during treatment compared with baseline for ADT patients. No significant changes in either cognitive tests or mood measures were noted for the healthy control group.

CONCLUSIONS

These findings, suggest that 9 months of combined androgen blockade may result in some adverse changes in cognition and mood. However, many but not all of these changes can return to baseline after cessation of ADT.

Direct progesterone receptor and indirect androgen receptor interactions with the kallikrein-related peptidase 4 gene promoter in breast and prostate cancer

Kallikrein 4 (KLK4) is a member of the human KLK gene family of serine proteases, many of which are implicated in hormone-dependent cancers. Like other KLKs, such as KLK3/PSA and KLK2, KLK4 gene expression is also regulated by steroid hormones in hormone-dependent cancers, although the transcriptional mechanisms are ill defined. Here, we have investigated the mechanisms mediating the hormonal regulation of KLK4 in breast (T47D) and prostate (LNCaP and 22Rv1) cancer cells. We have shown that KLK4 is only expressed in breast and prostate cancers that express the progesterone receptor (PR) and androgen receptor (AR), respectively. Expression analysis in PR- and AR-positive cells showed that the two predominant KLK4 variants that use either TIS1 or TIS2a/b are both up-regulated by progesterone in T47D cells and androgens in LNCaP cells. Two putative hormone response elements, K4.pPRE and K4.pARE at -2419 bp and -1005 bp, respectively, were identified in silico. Electrophoretic mobility shift assays and luciferase reporter experiments suggest that neither K4.pARE nor approximately 2.8 kb of the KLK4 promoter interacts directly with the AR to mediate KLK4 expression in LNCaP and 22Rv1 cells. However, we have shown that K4.pPRE interacts directly with the PR to up-regulate KLK4 gene expression in T47D cells. Further, chromatin immunoprecipitation experiments showed a time-dependent recruitment of the PR to the KLK4 promoter (-2496 to -2283), which harbors K4.pPRE. This is the first study to show that progesterone-regulated KLK4 expression in T47D cells is mediated partly by a hormone response element (K4.pPRE) at -2419 bp.

Diagnostic evaluation of PSA recurrence and review of hormonal management after radical prostatectomy

The aim of this review is to provide a discussion of the diagnostic evaluation of biochemical recurrence following radical prostatectomy (RP) and an overview of the postoperative hormonal treatment (HT) options. As no randomized trials in the clinical setting of postoperative prostate-specific antigen recurrence have been reported, there is no conclusive evidence that HT after RP will prolong survival or reduce morbidity. Non-traditional approaches, such as intermittent androgen deprivation, non-steroidal anti-androgens and combination of finasteride and non-steroidal anti-androgen, are investigated and may be acceptable options. Combinations of HT with radiotherapy and/or chemotherapy for treatment of recurrent prostate cancer are under study.

Bicalutamide-associated fulminant hepatotoxicity

Abstract Bicalutamide is a nonsteroidal antiandrogen used extensively during the start of androgen deprivation therapy with a luteinizing hormone-releasing hormone agonist to reduce occurrence of the symptoms of tumor flare in patients with metastatic prostate carcinoma. The most common adverse effects of bicalutamide are induced by its pharmacologic property of competitive androgen receptor blockade and include gynecomastia, hot flashes, fatigue, and decreased libido. Although not as common, increases in liver function test results are also seen with bicalutamide therapy. These elevations are typically transient, and patients remain asymptomatic. We describe a 59-year-old man with metastatic prostate carcinoma treated with bicalutamide as part of androgen deprivation therapy before starting chemotherapy. At baseline, his liver function test results and serum creatinine concentration were within normal limits, and an abdominal computed tomographic scan did not demonstrate liver metastasis. After 4 days of bicalutamide therapy, the patient came to the emergency department with complaints of abdominal pain, distension, and tenderness. His liver function tests were abnormal, and bicalutamide was discontinued. After 2 days of increasing liver function tests and symptoms of hepatotoxicity, the patient developed tachycardia and hypotension that was resistant to fluid resuscitation. Multiorgan damage was manifested by an alanine aminotransferase level greater than 40 times the upper limit of normal, serum creatinine concentration of 4.2 mg/dl, and troponin I level of 18 ng/ml. The patient died 8 days after bicalutamide therapy was begun secondary to multiorgan failure, most likely as a result of fulminant hepatotoxicity. The Naranjo adverse drug reaction probability scale showed a probable (score of 5) causal relationship between bicalutamide and fulminant hepatotoxicity. Fulminant hepatotoxicity is a rare but potentially fatal adverse effect of bicalutamide. Liver function tests should be monitored before and during bicalutamide therapy, even for patients who have previously completed a course of this therapy with no signs or symptoms of toxicity.

Bicalutamide failure in prostate cancer treatment: involvement of Multi Drug Resistance proteins

Prolonged bicalutamide treatment induced pathology regression although relapses with a more aggressive form of prostate cancer have been observed. This failure could be due to androgen receptor mutation. In the present work we hypothesized an alternative mechanism responsible for bicalutamide failure involving activity of ATP-binding cassette (ABC) pumps such as P-glycoprotein, Breast Cancer Receptor Protein (BCRP), and Multi Resistant Proteins (MRPs) that extrude the androgen antagonist from the cell membrane. As experimental models androgen-dependent (LnCap) and androgen-independent (PC-3) prostate cancer cell lines have been employed. Bicalutamide has been tested in the cell lines mentioned above in the absence and in the presence of MC18, our potent P-glycoprotein/BCRP/MRP1 inhibitor. The results displayed that bicalutamide antiproliferative effect at 72 h was ameliorated in LnCap cells (EC(50) from 51.9+/-6.1 microM to 17.8+/-2.6 microM in the absence and in the presence of MC18, respectively) and restored in PC-3 cells (EC(50) from 150+/-2.4 microM to 60+/-3.5 microM in the absence and in the presence of MC18, respectively). Moreover, we established the contribution of each transporter employing stable transfected cells (MDCK) overexpressing P-glycoprotein or BCRP or MRP1 pump. The results displayed that P-glycoprotein and BCRP were involved in bicalutamide efflux while MRP1 was unable to bind the antiandrogen drug.