Safety of antiandrogen therapy for treating prostate cancer

Efficacy and safety of spironolactone versus bicalutamide in female pattern hair loss: A retrospective comparative study

BACKGROUND

Female-pattern hair loss (FPHL) is characterized by decreased scalp hair density, thinning of hair shafts, and progressive miniaturization of hair follicles.

OBJECTIVE

To compare the safety and efficacy of spironolactone versus bicalutamide in female pattern hair loss [FPHL].

METHODS

The study design was retrospective, and all eligible females aged between 18 years and 50 years with FPHL were included. We identified 120 patients from our database who fulfilled the inclusion and exclusion criteria, and patients were then categorized into two groups, Group A comprising patients who were taking 100 mg of spironolactone once daily and Group B comprising patients who were taking 50 mg of bicalutamide once daily along with topical minoxidil 2% in both groups. Patient were analysed at approximately at 24 weeks from the commencement of the treatment.

RESULTS

Mean reduction in hair loss severity score on Sinclair scale was 19.51% in spironolactone group compared to 28.20% in bicalutamide group at 24 weeks, which was statistically significant. On global photographic assessment, marked improvement was seen in bicalutamide group compared to spironolactone group (p = 0.139).

CONCLUSIONS

Our study, though limited by its retrospective design and small sample size, showed that bicalutamide has greater efficacy and better safety profile in comparison to spironolactone in the treatment of FPHL.

[11C]Choline PET/CT in a Patient with Prostate Cancer Biochemical Recurrence Showing Two Suspicious Findings in the Breast and Liver

A 79-year-old man with prostate cancer (PCa) was referred to our center to perform a [11C]Choline PET/CT for biochemical recurrence. Positron emission tomography/computed tomography (PET/CT) scan detected PCa recurrence in the prostate gland and several pelvic and abdominal lymph nodes. Two abnormal uptakes were also identified in the right breast and in the liver, respectively. Breast histological findings turned out to be gynecomastia, while the liver lesion resulted in a benign perfusion anomaly at follow-up magnetic resonance imaging (MRI). Although incidental findings were benign in this case, it is important to always investigate abnormal uptakes of [11C]Choline, as it could be an expression of further metastases or synchronous malignancies such as breast cancer and hepatocellular carcinoma.

Nuclear Estrogen Receptors in Prostate Cancer: From Genes to Function

Estrogens are almost ubiquitous steroid hormones that are essential for development, metabolism, and reproduction. They exert both genomic and non-genomic action through two nuclear receptors (ERα and ERβ), which are transcription factors with disregulated functions and/or expression in pathological processes. In the 1990s, the discovery of an additional membrane estrogen G-protein-coupled receptor augmented the complexity of this picture. Increasing evidence elucidating the specific molecular mechanisms of action and opposing effects of ERα and Erβ was reported in the context of prostate cancer treatment, where these issues are increasingly investigated. Although new approaches improved the efficacy of clinical therapies thanks to the development of new molecules targeting specifically estrogen receptors and used in combination with immunotherapy, more efforts are needed to overcome the main drawbacks, and resistance events will be a challenge in the coming years. This review summarizes the state-of-the-art on ERα and ERβ mechanisms of action in prostate cancer and promising future therapies.

Androgenetic Alopecia: Therapy Update

Androgenetic alopecia (AGA), also known as male pattern hair loss (MPHL) or female pattern hair loss (FPHL), is the most common form of alopecia worldwide, and arises from an excessive response to androgens. AGA presents itself in a characteristic distribution unique to both sexes. Despite its prevalence, AGA can be quite challenging to treat. The condition is chronic in nature and stems from an interplay of genetic and environmental factors. There are only two US Food and Drug Administration (FDA)-approved drugs for the condition: topical minoxidil and oral finasteride. However, numerous non-FDA-approved treatments have been shown to be effective in treating AGA in various studies. Some of these treatments are relatively new and still to be explored, thus emphasizing the need for an updated review of the literature. In this comprehensive review, we discuss the evaluation of AGA and the mechanisms of action, costs, efficacies, and safety profiles of existing, alternative, and upcoming therapeutics for this widespread condition.

Bicalutamide and the new perspectives for female pattern hair loss treatment: What dermatologists should know

Female pattern hair loss (FPHL) is the most common form of alopecia in women. FPHL may compromise body image and strongly affect self-esteem, negatively impacting quality of life. Currently, the only Food and Drug Administration (FDA) approved drug for its treatment is topical minoxidil, with a variable response rate. Recently, a few studies in FPHL have pointed out bicalutamide as an emergent selective androgen receptor antagonist with a favorable safety and tolerability profile. This review aimed to summarize and discuss the key information on this new therapy for FPHL. Bicalutamide has no diuretic effect. It does not cross the blood-brain barrier, and it has little effect on serum luteinizing hormone. Additionally, bicalutamide was found to be effective on women presenting with other features of hyperandrogenism such as seborrhea, acne, and hirsutism with mild and well-tolerated adverse effects. Despite the high prevalence and psychosocial impairment, FPHL treatment remains challenging. Therefore, although future prospective, comparative, randomized clinical trials are essential to establish the ideal dose and efficacy of the drug, oral bicalutamide appears to be a promising option to expand the arsenal of FPHL treatment.

Risk of Fracture During Androgen Deprivation Therapy Among Patients With Prostate Cancer: A Systematic Review and Meta-Analysis of Cohort Studies

Background: Androgen deprivation therapy (ADT) suppresses the production of androgen, and ADT is broadly used for intermediate or higher risk disease including advanced and metastatic cancer. ADT is associated with numerous adverse effects derived from the pharmacological properties. Previous meta-analysis on fracture risk among ADT users possessed limited data without further subgroup analysis. Risk estimation of updated real-world evidence on ADT-related fracture remains unknown. Objectives: To assess the risk of fracture and fracture requiring hospitalization associated with ADT among prostate cancer population on different disease conditions, treatment regimen, dosage level, fracture sites. Methods: The Cochrane Library, PubMed, and Embase databases were systematically screened for eligible cohort studies published from inception to March 2020. Two authors independently reviewed all the included studies. The risks of any fracture and of fracture requiring hospitalization were assessed using a random-effects model, following by leave-one-out, stratified, and sensitivity analyses. The Grading of Recommendations Assessments, Development and Evaluations (GRADE) system was used to grade the certainty of evidence. Results: Sixteen eligible studies were included, and total population was 519,168 men. ADT use is associated with increasing fracture risk (OR, 1.39; 95% CI, 1.26-1.52) and fracture requiring hospitalization (OR, 1.55; 95% CI, 1.29-1.88). Stratified analysis revealed that high-dose ADT results in an elevated risk of fracture with little statistical heterogeneity, whereas sensitivity analysis restricted to adjust for additional factors indicated increased fracture risks for patients with unknown stage prostate cancer or with no restriction on age with minimal heterogeneity. The GRADE level of evidence was moderate for any fracture and low for fracture requiring hospitalization. Conclusion: Cumulative evidence supports the association of elevated fracture risk with ADT among patients with prostate cancer, including those with different disease conditions, treatment regimens, dose levels, and fracture sites. Further prospective trials with intact information on potential risk factors on fracture under ADT use are warranted to identify the risky population.

Cellular Targeting of Oligonucleotides by Conjugation with Small Molecules

Drug candidates derived from oligonucleotides (ON) are receiving increased attention that is supported by the clinical approval of several ON drugs. Such therapeutic ON are designed to alter the expression levels of specific disease-related proteins, e.g., by displaying antigene, antisense, and RNA interference mechanisms. However, the high polarity of the polyanionic ON and their relatively rapid nuclease-mediated cleavage represent two major pharmacokinetic hurdles for their application in vivo. This has led to a range of non-natural modifications of ON structures that are routinely applied in the design of therapeutic ON. The polyanionic architecture of ON often hampers their penetration of target cells or tissues, and ON usually show no inherent specificity for certain cell types. These limitations can be overcome by conjugation of ON with molecular entities mediating cellular 'targeting', i.e., enhanced accumulation at and/or penetration of a specific cell type. In this context, the use of small molecules as targeting units appears particularly attractive and promising. This review provides an overview of advances in the emerging field of cellular targeting of ON via their conjugation with small-molecule targeting structures.

Pharmacological Approaches to Controlling Cardiometabolic Risk in Women with PCOS

Polycystic ovary syndrome (PCOS) is characterized by elevated androgen production and subclinical changes in cardiovascular and metabolic risk markers. Total cholesterol, high-density lipoprotein (HDL) cholesterol, fasting glucose, and fasting insulin appear to increase specifically in PCOS compared with fertile women. PCOS also confers an increased risk of cardiometabolic disease in later life. Novel biomarkers such as serum’s cholesterol efflux capacity and blood-derived macrophage activation profile may assist in more accurately defining the cardiometabolic risk profile in these women. Aldosterone antagonists, androgen receptor antagonists, 5α-reductase inhibitors, and synthetic progestogens are used to reduce hyperandrogenism. Because increased insulin secretion enhances ovarian androgen production, short-term treatment with metformin and other hypoglycemic agents results in significant weight loss, favorable metabolic changes, and testosterone reduction. The naturally occurring inositols display insulin-sensitizing effects and may be also used in this context because of their safety profile. Combined oral contraceptives represent the drug of choice for correction of androgen-related symptoms. Overall, PCOS management remains focused on specific targets including assessment and treatment of cardiometabolic risk, according to disease phenotypes. While new options are adding to established therapeutic approaches, a sometimes difficult balance between efficacy and safety of available medications has to be found in individual women.

Efficacy and Safety of Nilutamide in Patients with Metastatic Prostate Cancer who Underwent Orchiectomy: A Systematic Review and Metaanalysis

BACKGROUND

Prostate cancer is the sixth leading cause of death, among all cancer deaths By 2030, this burden is expected to increase with 1.7 million new cases and 499,000 new deaths. We aimed to evaluate the efficacy and safety of Nilutamide in metastatic prostate cancer (mPCa) patients who underwent orchiectomy.

METHODS

A comprehensive search was conducted in the Medline/PubMed and Cochrane Library. References from included studies and studies from clinicaltrials.gov were explored without language and date restrictions. We included only randomized controlled trials, comparing the safety and efficacy of Nilutamide in Metastatic Prostate Cancer (mPCa) patients who underwent orchiectomy with placebo. The outcomes of concerns were survival and the response of drug and safety.. Quality of the included studies was assessed using the Cochrane Risk of Bias Tool. Two authors were independently involved in the study selection, data extraction and quality assessment. Disagreements between the two reviewers were resolved by consulting a third reviewer.

RESULTS

A total of five out of 244 studies were included in meta-analysis involving1637 participants. Nilutamide group showed improved response rate (RR=1.77, 95%CI 1.46-2.14, p<0.00001), disease progression (RR=0.59, 95%CI 0.47-0.73, p<0.00001), complete response (RR=2.13, 95%CI 1.40-3.23, p=0.003) and clinical benefit (RR=1.23, 95%CI 1.13-1.34, p<0.00001) when compared to placebo; however, stable disease favored the control group (RR=0.80, 95%CI 0.68-0.94, p=0.007). In addition, patients on Nilutamide showed prolonged progression-free survival and overall survival. Nausea and vomiting were the most common adverse events reported in Nilutamide group.

CONCLUSION

Evidence suggests that patients with mPCa who underwent orchiectomy receiving Nilutamide showed significant improvement in progression-free survival and overall survival response rate and clinical benefits in comparison with the placebo group.

Influence of androgen deprivation therapy on serum urate levels in patients with prostate cancer: A retrospective observational study

OBJECTIVES

Although estrogenic modulation of serum urate levels is well-known, the androgenic effect on urate homeostasis remains controversial. We investigated the effect of androgen deprivation therapy (ADT) on serum urate levels.

METHODS

We retrospectively enrolled a total of 489 prostate cancer patients with available serum urate levels at baseline and 3 and 6 months after ADT (n = 150) or prostate surgery (n = 339). We extracted the demographic, clinical, and laboratory data from a data warehouse and compared the changes in urate levels between the two treatment groups and between the different ADT regimens (with versus without luteinizing hormone-releasing hormone (LHRH) agonists) using generalized estimating equation (GEE).

RESULTS

The baseline urate levels and the proportion of hyperuricemic subjects were comparable between the two groups. After 6 months, the urate levels were significantly decreased (by -0.66 mg/dL, 95% confidence interval (CI) [-0.81 to -0.51]) in the ADT group, whereas they did not significantly change in the surgery group in the univariate GEE analysis. The ADT group (4.7% from 18.0% at baseline) had a significantly lower proportion of hyperuricemic patients than surgery group (16.5% from 15.9% at baseline) at 6-month (p < 0.001). Regardless of whether LHRH agonists were used, the serial urate levels were lowered by the ADT. Temporal changes in the urate levels were significantly associated with the treatment group, baseline hyperuricemia, and poor functional or advanced cancer status. The ADT-related serum urate level reduction also remained significant in the multivariate GEE analysis (regression coefficient = -0.43 [-0.67 to -0.19] after 3 months and -0.37 [-0.64 to -0.10] after 6 months). Moreover, propensity-score-matched analyses yielded the same results.

CONCLUSIONS

Our results showed that longitudinal serum urate levels were significantly reduced in men receiving ADT. This finding suggests that androgen could have an independent role in urate homeostasis.

Permitted Daily Exposure of the Androgen Receptor Antagonist Flutamide

This report aims to determine the permitted daily exposure (PDE) of flutamide, an androgen receptor blocker, as directed by guideline EMA/CHMP/CVPM/SWP/169430/2012 that came into effect on June 2015. A literature review was conducted to identify toxicity studies of flutamide. Hazards and sensitive endpoints were determined. Based on the no adverse effect levels (NOAELs) and lowest observed adverse effect levels (LOAELs) reported from both reproductive, developmental, and 28-day toxicity studies the PDE was calculated. Most of the toxicity studies converge toward a NOAEL of 1 mg/kg/d that translates to a PDE of 0.1 mg/d. However, taking into consideration the worst case scenarios for additional safety a PDE of 0.025 mg/d (25 μg/d) was calculated based on a reported NOAEL of 0.25 mg/kg/d. A PDE of 0.05 mg/d (50 μg/d) was also calculated from reproductive/developmental toxicity studies, which is in close agreement with the PDE from the 28-day toxicity studies. Considering the lowest PDE of 0.025 mg/d, residual flutamide at this dose is unlikely to pose any risk to humans. Nonmonotonic dose response (NMDR) effects of flutamide were not supported by literature. Oral route of administration was considered.

Baicalein suppresses the androgen receptor (AR)-mediated prostate cancer progression via inhibiting the AR N-C dimerization and AR-coactivators interaction

BACKGROUND

Androgen receptor (AR) plays a critical role in prostate cancer (PCa) development and progression. Androgen deprivation therapy with antiandrogens to reduce androgen biosynthesis or prevent androgens from binding to AR are widely used to suppress AR-mediated PCa growth. However, most of ADT may eventually fail with development of the castration resistance after 12-24 months. Here we found that a natural product baicalein can effectively suppress the PCa progression via targeting the androgen-induced AR transactivation with little effect to AR protein expression.

METHODS

PCa cells including LNCaP, CWR22Rv1, C4-2, PC-3, and DU145, were treated with baicalein and luciferase assay was used to evaluate their effect on the AR transactivation. Cell growth and IC50 were determined by MTT assay after 48 hrs treatment. RT-PCR was used to evaluate the mRNA levels of AR target genes including PSA, TMPRSS2, and TMEPA1. Western blot was used to determine AR and PSA protein expression.

RESULTS

The natural product of baicalein can selectively inhibit AR transactivation with little effect on the other nuclear receptors, including ERα, and GR. At a low concentration, 2.5 μM of baicalein effectively suppresses the growth of AR-positive PCa cells, and has little effect on AR-negative PCa cells. Mechanism dissection suggest that baicalein can suppress AR target genes (PSA, TMPRSS2, and TMEPA1) expression in both androgen responsive LNCaP cells and castration resistant CWR22Rv1 cells, that may involve the inhibiting the AR N/C dimerization and AR-coactivators interaction.

CONCLUSIONS

Baicalein may be developed as an effective anti-AR therapy via its ability to inhibit AR transactivation and AR-mediated PCa cell growth.

Cardiovascular toxicities of systemic treatments of prostate cancer

Prostate cancer is the most common cancer in men, with an incidence that is expected to increase in the coming years. Prostate cancer is usually diagnosed in men >65 years of age, thus the concurrent presence of cardiovascular diseases might influence the treatment, owing to the increased risk of cardiovascular mortality. The introduction of new drugs, such as abiraterone and enzalutamide for the management of metastatic disease has created further interest in treatment-related cardiovascular toxicities, although limited data from trials specifically designed to identify cardiovascular toxicities of these agents are currently available. The only available data are derived from published phase II-III study reports, expanded access or compassionate use programmes and meta-analyses of the effects of systemic therapies that are already approved for use in clinical practice or are in the early phases of development. These data are conflicting, although they seem to suggest that certain drugs are associated with an increased risk of cardiovascular adverse events. Clinical trial methodology could be improved by the enrolment of greater numbers of patients >65 years of age, and the use of comprehensive cardiological evaluations. Moreover, closer collaboration between oncologists and cardiologists is essential for the identification and/or management of cardiovascular adverse events in patients with prostate cancer.

Androgen receptor antagonists compromise T cell response against prostate cancer leading to early tumor relapse

Surgical and medical androgen deprivation therapy (ADT) is a cornerstone for prostate cancer treatment, but relapse usually occurs. We herein show that orchiectomy synergizes with immunotherapy, whereas the more widely used treatment of medical ADT involving androgen receptor (AR) antagonists suppresses immunotherapy. Furthermore, we observed that the use of medical ADT could unexpectedly impair the adaptive immune responses through interference with initial T cell priming rather than in the reactivation or expansion phases. Mechanistically, we have revealed that inadvertent immunosuppression might be potentially mediated by a receptor shared with γ-aminobutyric acid. Our data demonstrate that the timing and dosing of antiandrogens are critical to maximizing the antitumor effects of combination therapy. This study highlights an underappreciated mechanism of AR antagonist-mediated immunosuppression and provides a new strategy to enhance immune response and prevent the relapse of advanced prostate cancer.

Knocking Down TMPRSS2-ERG Fusion Oncogene by siRNA Could be an Alternative Treatment to Flutamide

Our purpose was to develop a new pharmacological approach for the treatment of prostate cancer (PCa), the most common neoplasia in men. Recently, we developed siRNA against the fusion oncogene TMPRSS2-ERG found in 50% of patients and showed an antitumoral activity in animal model. Herein, we want to compare or combine the developed siRNA to flutamide (FLU), one of the gold-standard treatment of PCa. Therefore, concomitant or subsequent association of FLU to siRNA TMPRSS2-ERG was performed in VCaP cells and in SCID mice bearing xenografted VCaP tumors. ERG, androgen receptor, cleaved-caspase-3 as well as phase 1 and 2 drug-metabolizing enzymes were investigated within tumors. We observed similar results in terms of TMPRSS2-ERG knock-down and cell viability impairment for all distinct schedules of administration. The association of siRNA TMPRSS2-ERG-squalene nanoparticles with flutamide displayed similar tumor growth inhibition as mice treated with siRNA TMPRSS2-ERG-squalene nanoparticles alone and was paralleled with modification of expression of ERG, androgen receptor, and cleaved-caspase-3. Phase 1 and 2 enzymes were essentially affected by FLU and reverted when combined with squalenoylated siRNA. In conclusion, these results confirm the therapeutic effectiveness of squalenoyl siRNA nanomedicine for PCa based on siRNA TMPRSS2-ERG.