The role of adrenal derived androgens in castration resistant prostate cancer

Effect of age on androgens pattern in cyclic mares

Androgens are produced in both sexes. In females produced by the adrenal gland and the ovaries they play a crucial role in regulating ovarian function, estrogen synthesis and follicular growth. Age leads to a reduction in androgen concentrations, although, at present, these mechanisms are not elucidated in mares. The objective of this study was to evaluate the concentrations of testosterone (T), androstenedione (A4) and dehydroepiandrosterone (DHEA) in mares of different ages. Blood samples were drawn from seventy cyclic Spanish Purebred mares belonging to five age groups: 3-5 years, 6-9 years, 10-13 years, 14-16 years and > 16 years. The concentrations of T, A4 and DHEA were determined by EIA, validated specifically for horses. Mares aged 3-5, 6-9 and 10-13 years had higher T concentrations (P < 0.05) than mares aged >16 years, and mares aged 6-9 years had also higher concentrations than those 14-16 years old (P < 0.05). A4 concentrations were lower (P < 0.05) in mares >16 years old when compared with those of other age groups. DHEA concentrations were lower (P < 0.05) in mares 14-16 years and > 16 years old when compared with those of other age groups. DHEA was positively correlated with T (r = 0.61; P < 0.05) and A4 (r = 0.51; P < 0.05). Age induces reduction in androgens' synthesis in physiologically cyclic Spanish Purebred mares. These physiological variations must be duly considered for a correct and objective interpretation of the analytical data.

Extra-nuclear and cytoplasmic steroid receptor signalling in hormone dependent cancers

Steroid hormone receptors are key mediators in the execution of hormone action through a combination of genomic and non-genomic action. Since their isolation and characterisation in the early 20th Century much of our understanding of the biological actions of steroid hormones are underpinned by their activated receptor activity. Over the past two decades there has been an acceleration of more omics-based research which has resulted in a major uptick in our comprehension of genomic steroid action. However, it is well understood that steroid hormones can induce very rapid signalling events in tandem with their genomic actions wherein they exert their influence through alterations in gene expression. Thus the totality of genomic and non-genomic steroid action occurs in a simultaneous and reciprocal manner and a greater appreciation of whole cell action is required to fully evaluate steroid hormone activity in vivo. In this mini-review we outline the most recent developments in non-genomic steroid action and cytoplasmic steroid hormone receptor biology in endocrine-related cancers with a focus on the 3-keto steroid receptors, in particular the androgen receptor.

DHODH inhibition represents a therapeutic strategy and improves abiraterone treatment in castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) is an aggressive disease with poor prognosis, and there is an urgent need for more effective therapeutic targets to address this challenge. Here, we showed that dihydroorotate dehydrogenase (DHODH), an enzyme crucial in the pyrimidine biosynthesis pathway, is a promising therapeutic target for CRPC. The transcript levels of DHODH were significantly elevated in prostate tumors and were negatively correlated with the prognosis of patients with prostate cancer. DHODH inhibition effectively suppressed CRPC progression by blocking cell cycle progression and inducing apoptosis. Notably, treatment with DHODH inhibitor BAY2402234 activated androgen biosynthesis signaling in CRPC cells. However, the combination treatment with BAY2402234 and abiraterone decreased intratumoral testosterone levels and induced apoptosis, which inhibited the growth of CWR22Rv1 xenograft tumors and patient-derived xenograft organoids. Taken together, these results establish DHODH as a key player in CRPC and as a potential therapeutic target for advanced prostate cancer.

Adrenal-Permissive Germline HSD3B1 Allele and Prostate Cancer Outcomes

Importance

The adrenal androgen-metabolizing 3β-hydroxysteroid dehydrogenase-1 enzyme, encoded by the HSD3B1 gene, catalyzes the rate-limiting step necessary for synthesizing nontesticular testosterone and dihydrotestosterone production. The common adrenal-permissive HSD3B1(1245C) allele is responsible for encoding the 3β-HSD1 protein with decreased susceptibility to degradation resulting in higher extragonadal androgen synthesis. Retrospective studies have suggested an association of the HSD3B1 adrenal-permissive homozygous genotype with androgen deprivation therapy resistance in prostate cancer.

Objective

To evaluate differences in mortality outcomes by HSD3B1 genetic status among men with prostate cancer.

Design, Setting, and Participants

This cohort study of patients with prostate cancer who were enrolled in the Million Veteran Program within the Veterans Health Administration (VHA) system between 2011 and 2023 collected genotyping and phenotyping information.

Exposure

HSD3B1 genotype status was categorized as AA (homozygous adrenal-restrictive), AC (heterozygous adrenal-restrictive), or CC (homozygous adrenal-permissive).

Main Outcomes and Measures

The primary outcome of this study was prostate cancer-specific mortality (PCSM), defined as the time from diagnosis to death from prostate cancer, censored at the date of last VHA follow-up. Secondary outcomes included incidence of metastases and PCSM in predefined subgroups.

Results

Of the 5287 participants (median [IQR] age, 69 [64-74] years), 402 (7.6%) had the CC genotype, 1970 (37.3%) had the AC genotype, and 2915 (55.1%) had the AA genotype. Overall, the primary cause of death for 91 patients (1.7%) was prostate cancer. Cumulative incidence of PCSM at 5 years after prostate cancer diagnosis was higher among men with the CC genotype (4.0%; 95% CI, 1.7%-6.2%) compared with the AC genotype (2.1%; 95% CI, 1.3%-2.8%) and AA genotype (1.9%; 95% CI, 1.3%-2.4%) (P = .02). In the 619 patients who developed metastatic disease at any time, the cumulative incidence of PCSM at 5 years was higher among patients with the CC genotype (36.0%; 95% CI, 16.7%-50.8%) compared with the AC genotype (17.9%; 95% CI, 10.5%-24.7%) and AA genotype (18.5%; 95% CI, 12.0%-24.6%) (P = .01).

Conclusions and Relevance

In this cohort study of US veterans undergoing treatment for prostate cancer at the VHA, the HSD3B1 CC genotype was associated with inferior outcomes. The HSD3B1 biomarker may help identify patients who may benefit from therapeutic targeting of 3β-hydroxysteroid dehydrogenase-1 and the androgen-signaling axis.

Light-switchable diazocines as potential inhibitors of testosterone-synthesizing 17β-hydroxysteroid dehydrogenase 3

In patients with prostate carcinoma as well as in some other cancer types, the reduction of testosterone levels is desired because the hormone stimulates cancer cell growth. One molecular target for this goal is the inhibition of 17β-hydroxysteroid dehydrogenase type 3 (17βHSD3), which produces testosterone from its direct precursor androstenedione. Recent research in this field is trying to harness photopharmacological properties of certain compounds so that the inhibitory effect could be turned on and off by irradiation. Seven new light-switchable diazocines were investigated with regard to their inhibition of 17βHSD3. For this purpose, transfected HEK-293 cells and isolated microsomes were treated with the substrate and the potential inhibitors with and without irradiation for an incubation period of 3 or 5 h. The amount of generated testosterone was measured by UHPLC and compared between samples and control as well as between irradiated and non-irradiated samples. There was no significant difference between samples with and without irradiation. However, four of the seven diazocines led to a significantly lower testosterone production both in cell and in microsome assays. In some of the irradiated samples, a partial destruction of the diazocines was observed, indicated by an additional UHPLC peak. However, the influence on the inhibition is negligible, because the majority of the substance remained intact. In conclusion, new inhibitors of 17βHSD3 have been found, but so far without the feature of a light switch, since the configurational alteration of the diazocines by irradiation did not lead to a change in bioactivity. Further modification might help to find a light-switching molecule that inhibits only in one configuration.

Effect of Essential Oil Components on the Activity of Steroidogenic Cytochrome P450

Endocrine-disrupting chemicals (EDCs) may impact the development of prostate cancer (PCa) by altering the steroid metabolism. Although their exact mechanism of action in controlling tumor growth is not known, EDCs may inhibit steroidogenic enzymes such as CYP17A1 or CYP19A1 which are involved in the production of androgens or estrogens. High levels of circulating androgens are linked to PCa in men and Polycystic Ovary Syndrome (PCOS) in women. Essential oils or their metabolites, like lavender oil and tea tree oil, have been reported to act as potential EDCs and contribute towards sex steroid imbalance in cases of prepubertal gynecomastia in boys and premature thelarche in girls due to the exposure to lavender-based fragrances. We screened a range of EO components to determine their effects on CYP17A1 and CYP19A1. Computational docking was performed to predict the binding of essential oils with CYP17A1 and CYP19A1. Functional assays were performed using the radiolabeled substrates or Liquid Chromatography-High-Resolution Mass Spectrometry and cell viability assays were carried out in LNCaP cells. Many of the tested compounds bind close to the active site of CYP17A1, and (+)-Cedrol had the best binding with CYP17A1 and CYP19A1. Eucalyptol, Dihydro-β-Ionone, and (-)-α-pinene showed 20% to 40% inhibition of dehydroepiandrosterone production; and some compounds also effected CYP19A1. Extensive use of these essential oils in various beauty and hygiene products is common, but only limited knowledge about their potential detrimental side effects exists. Our results suggest that prolonged exposure to some of these essential oils may result in steroid imbalances. On the other hand, due to their effect on lowering androgen output and ability to bind at the active site of steroidogenic cytochrome P450s, these compounds may provide design ideas for novel compounds against hyperandrogenic disorders such as PCa and PCOS.

A common germline variant in CYP11B1 is associated with adverse clinical outcome of treatment with abiraterone or enzalutamide

Extragonadal androgens play a pivotal role in prostate cancer disease progression on androgen receptor signaling inhibitors (ARSi), including abiraterone and enzalutamide. We aimed to investigate if germline variants in genes involved in extragonadal androgen synthesis contribute to resistance to ARSi and may predict clinical outcomes on ARSi. We included ARSi naive metastatic prostate cancer patients treated with abiraterone or enzalutamide and determined 18 germline variants in six genes involved in extragonadal androgen synthesis. Variants were tested in univariate and multivariable analysis for the relation with overall survival (OS) and time to progression (TTP) by Cox regression, and PSA response by logistic regression. A total of 275 patients were included. From the investigated genes CYP17A1, HSD3B1, CYP11B1, AKR1C3, SRD5A1 and SRD5A2, only rs4736349 in CYP11B1 in homozygous form (TT), present in 54 patients (20%), was related with a significantly worse OS (HR = 1.71, 95% CI 1.09 - 2.68, p = 0.019) and TTP (HR = 1.50, 95% CI 1.08 - 2.09, p = 0.016), and was related with a significantly less frequent PSA response (OR = 0.48, 95% CI 0.24 - 0.96, p = 0.038) on abiraterone or enzalutamide in a multivariable analysis. The frequent germline variant rs4736349 in CYP11B1 is, as homozygote, an independent negative prognostic factor for treatment with abiraterone or enzalutamide in ARSi naive metastatic prostate cancer patients. Our findings warrant prospective investigation of this potentially important predictive biomarker.

Pinostilbene inhibits full-length and splice variant of androgen receptor in prostate cancer

Prostate cancer is the most prevalent cancer in men worldwide and is promoted by the sex hormone androgen. Expression of androgen from the testis can be significantly reduced through castration. However, as most prostate cancer patients acquire castration resistance, additional therapeutic solutions are necessary. Although anti-androgens, such as enzalutamide, have been used to treat castration-resistant prostate cancer (CRPC), enzalutamide-resistant CRPC (Enz-resistant CRPC) has emerged. Therefore, development of novel treatments for Enz-resistant CRPC is urgent. In this study, we found a novel anti-androgen called pinostilbene through screening with a GAL4-transactivation assay. We confirmed that pinostilbene directly binds to androgen receptor (AR) and inhibits its activation and translocalization. Pinostilbene treatment also reduced the protein level and downstream gene expression of AR. Furthermore, pinostilbene reduced the protein level of AR variant 7 in the Enz-resistant prostate cancer cell line 22Rv1 and inhibited cell viability and proliferation. Our results suggest that pinostilbene has the potential to treat Enz-resistant CRPC.

Circulating adrenal 11-oxygenated androgens are associated with clinical outcome in endometrial cancer

Context

Recent evidence support that androgens play an important role in the etiology of endometrial cancer (EC). Adrenal-derived 11-oxygenated androgens are highly potent agonists of the androgen receptor (AR), comparable to testosterone (T) and dihydrotestosterone (DHT) that have not been studied in the context of EC.

Methodology

We studied a cohort of 272 newly diagnosed postmenopausal EC cases undergoing surgical treatment. Circulating concentrations of seven 11-oxygenated androgens including precursors, potent androgens and their metabolites were established in serum samples collected before and 1 month after surgery using a validated liquid chromatography tandem mass spectrometry method (LC-MS/MS). Free (unconjugated) and total (free + sulfate and glucuronide conjugates following enzymatic hydrolysis) were analyzed in relation to clinicopathological features, recurrence and disease-free survival (DFS).

Results

Levels of 11-oxygenated androgens were weakly correlated to those of canonical androgens such as testosterone (T) and dihydrotestosterone (DHT), with no evidence of their association with clinicopathological features. Levels of 11-oxygenated androgens declined after surgery but remained higher in overweight and obese compared to normal weight cases. Higher levels of preoperative free 11-ketoandrosterone (11KAST) were associated with an increased risk of recurrence (Hazard ratio (HR) of 2.99 (95%CI=1.09-8.18); P=0.03). Postoperative free 11β-hydroxyandrosterone (11OHAST) levels were adversely associated with recurrence and DFS (HR = 3.23 (1.11-9.40); P=0.03 and 3.27 (1.34-8.00); P=0.009, respectively).

Conclusion

11-oxygenated androgen metabolites emerge as potential prognostic markers of EC.

Clostridium scindens metabolites trigger prostate cancer progression through androgen receptor signaling

Prostate cancer (PCa) is one of the most common malignancies in men; recently, PCa-related mortality has increased worldwide. Although androgen deprivation therapy (ADT) is the standard treatment for PCa, patients often develop aggressive castration-resistant PCa (CRPC), indicating the presence of an alternative source of androgen. Clostridium scindens is a member of the gut microbiota and can convert cortisol to 11β-hydroxyandrostenedione (11β-OHA), which is a potent androgen precursor. However, the effect of C. scindens on PCa progression has not been determined. In this study, androgen-dependent PCa cells (LNCaP) were employed to investigate whether C. scindens-derived metabolites activate androgen receptor (AR), which is a pivotal step in the development of PCa. Results showed that cortisol metabolites derived from C. scindens-conditioned medium promoted proliferation and enhanced migration of PCa cells. Furthermore, cells treated with these metabolites presented activated AR and stimulated AR-regulated genes. These findings reveal that C. scindens has the potential to promote PCa progression via the activation of AR signaling. Further studies on the gut-prostate axis may help unravel an alternative source of androgen that triggers CRPC exacerbation.

Preclinical models of prostate cancer - modelling androgen dependency and castration resistance in vitro, ex vivo and in vivo

Prostate cancer is well known to be dependent on the androgen receptor (AR) for growth and survival. Thus, AR is the main pharmacological target to treat this disease. However, after an initially positive response to AR-targeting therapies, prostate cancer will eventually evolve to castration-resistant prostate cancer, which is often lethal. Tumour growth was initially thought to become androgen-independent following treatments; however, results from molecular studies have shown that most resistance mechanisms involve the reactivation of AR. Consequently, tumour cells become resistant to castration - the blockade of testicular androgens - and not independent of AR per se. However, confusion still remains on how to properly define preclinical models of prostate cancer, including cell lines. Most cell lines were isolated from patients for cell culture after evolution of the tumour to castration-resistant prostate cancer, but not all of these cell lines are described as castration resistant. Moreover, castration refers to the blockade of testosterone production by the testes; thus, even the concept of "castration" in vitro is questionable. To ensure maximal transfer of knowledge from scientific research to the clinic, understanding the limitations and advantages of preclinical models, as well as how these models recapitulate cancer cell androgen dependency and can be used to study castration resistance mechanisms, is essential.

The role of 11-oxygenated androgens in prostate cancer

11-oxygenated androgens are a class of steroids capable of activating the androgen receptor (AR) at physiologically relevant concentrations. In view of the AR as a key driver of prostate cancer (PC), these steroids are potential drivers of disease and progression. The 11-oxygenated androgens are adrenal-derived, and persist after androgen deprivation therapy (ADT), the mainstay treatment for advanced PC. Consequently, these steroids are of particular interest in the castration-resistant prostate cancer (CRPC) setting. The principal androgen of the pathway, 11-ketotestosterone (11KT), is a potent AR agonist and the predominant circulating active androgen in CRPC patients. Additionally, several precursor steroids are present in the circulation which can be converted into active androgens by steroidogenic enzymes present in PC cells. In vitro evidence suggests that adaptations frequently observed in CRPC favour the intratumoral accumulation of 11-oxygenated androgens in particular. Still, apparent gaps in our understanding of the physiology and role of the 11-oxygenated androgens remain. In particular, in vivo and clinical evidence supporting these in vitro findings is limited. Despite recent advances, a comprehensive assessment of intratumoral concentrations has not yet been performed. The exact contribution of the 11-oxygenated androgens to CRPC progression therefore remains unclear. This review will focus on the current evidence linking the 11-oxygenated androgens to PC, will highlight current gaps in our knowledge, and will provide insight into the potential clinical importance of the 11-oxygenated androgens in the CRPC setting based on the current evidence.

Antiandrogenic Effects of a Polyphenol in Carex kobomugi through Inhibition of Androgen Synthetic Pathway and Downregulation of Androgen Receptor in Prostate Cancer Cell Lines

Prostate cancer (PC) represents the most common cancer disease in men. Since high levels of androgens increase the risk of PC, androgen deprivation therapy is the primary treatment; however this leads to castration-resistant PC (CRPC) with a poor prognosis. The progression to CRPC involves ectopic androgen production in the adrenal glands and abnormal activation of androgen signaling due to mutations and/or amplification of the androgen receptor (AR) as well as activation of androgen-independent proliferative pathways. Recent studies have shown that adrenal-derived 11-oxygenated androgens (11-ketotestosterone and 11-ketodihydrotestosterone) with potencies equivalent to those of traditional androgens (testosterone and dihydrotestosterone) are biomarkers of CRPC. Additionally, dehydrogenase/reductase SDR family member 11 (DHRS11) has been reported to be a 17β-hydroxysteroid dehydrogenase that catalyzes the production of the 11-oxygenated and traditional androgens. This study was conducted to evaluate the pathophysiological roles of DHRS11 in PC using three LNCaP, C4-2 and 22Rv1 cell lines. DHRS11 silencing and inhibition resulted in suppression of the androgen-induced expression of AR downstream genes and decreases in the expression of nuclear AR and the proliferation marker Ki67, suggesting that DHRS11 is involved in androgen-dependent PC cell proliferation. We found that 5,7-dihydroxy-8-methyl-2-[2-(4-hydroxyphenyl)ethenyl]-4H-1-benzopyran-4-one (Kobochromone A, KC-A), an ingredient in the flowers of Carex kobomugi, is a novel potent DHRS11 inhibitor (IC₅₀ = 0.35 μM). Additionally, KC-A itself decreased the AR expression in PC cells. Therefore, KC-A suppresses the androgen signaling in PC cells through both DHRS11 inhibition and AR downregulation. Furthermore, KC-A enhanced the anticancer activity of abiraterone, a CRPC drug, suggesting that it may be a potential candidate for the development of drugs for the prevention and treatment of CRPC.

Steroidogenesis in castration-resistant prostate cancer

Castration resistance is in part attributable to aberrant activation of androgen receptor (AR) signaling by the intracrine activation of androgen precursors derived from adrenal glands. To overcome this, novel AR pathway inhibitors (ARPIs) that suppress androgen synthesis by CYP17 inhibition or AR activation by antiandrogen effects have been developed. However, primary or acquired resistance to these ARPIs occurs; in turn attributable, at least in part, to the maintained androgen milieu despite intensive suppression of AR signaling similar to castration resistance. In addition to the classical pathway to produce potent androgens such as testosterone and dihydrotestosterone, the alternative pathway and the backdoor pathway which bypasses testosterone to produce dihydrotestosterone have been shown to play a role in intratumor steroidogenesis. Furthermore, the 11β-hydroxyandrostenedione pathway to produce the potent oxygenated androgens 11-ketotestosterone and 11-ketodihydrotestosterone has been suggested to be functional in prostate cancer. These steroidogenesis pathways produce potent androgens that promote tumor resistance to endocrine therapy including novel ARPIs. Here, we overview the current evidence on the pathological androgen milieu by altered metabolism and transport in prostate cancer, leading to resistance to endocrine therapy.

Remission of progressive metastatic castration-resistant prostate cancer during abiraterone therapy following unilateral adrenalectomy for a functioning adrenal adenoma

Despite advances and introduction of new therapies in the last decade, metastatic castration-resistant prostate cancer (mCRPC) has a poor prognosis. The development of androgen axis-targeted therapies such as abiraterone acetate, enzalutamide and darolutamide can prolong survival in mCPRC; however, resistance remains a barrier to prolonged response, necessitating exploration into resistance mechanisms and locoregional therapies. Here, we describe a patient with mCRPC that was progressing on abiraterone acetate. He was also found to have primary hyperaldosteronism from a functional adrenal adenoma, and thus he had a partial adrenalectomy to remove this tumour. Pathology confirmed an aldosterone-producing adrenal adenoma. After his adrenalectomy, he had a sharp decline in both his PSA (prostate specific antigen) and testosterone levels, and he enjoyed a year-long period of remission after his adrenalectomy. We propose several explanations for his response, the most likely being that his adenoma was producing both aldosterone and androgens. This is a unique case of mCRPC responding to partial adrenalectomy from a functional adrenal adenoma, and it raises insights that warrant further investigation into underlying mechanisms of resistance to androgen-targeted therapies.

An update on adrenocortical cell lines of human origin

Adrenocortical carcinoma (ACC) is a rare, heterogenous and highly malignant disease. Management of ACC is dependent on disease stage with complete surgical resection as the only potentially curative option. However, advanced, un-resectable, metastatic stages and also recurrences often require systemic treatments, which are unfortunately nowadays still unsatisfactory. The scarcity of preclinical models reflecting patient heterogeneities and furthermore drug-resistant phenotypes, has hampered the progress and development of new therapies in recent years. In this review, we provide an overview on the classical models and substantial progress which has been made over the last years in context of this aggressive disease.

Advances in the Current Understanding of the Mechanisms Governing the Acquisition of Castration-Resistant Prostate Cancer

Despite aggressive treatment and androgen-deprivation therapy, most prostate cancer patients ultimately develop castration-resistant prostate cancer (CRPC), which is associated with high mortality rates. However, the mechanisms governing the development of CRPC are poorly understood, and androgen receptor (AR) signaling has been shown to be important in CRPC through AR gene mutations, gene overexpression, co-regulatory factors, AR shear variants, and androgen resynthesis. A growing number of non-AR pathways have also been shown to influence the CRPC progression, including the Wnt and Hh pathways. Moreover, non-coding RNAs have been identified as important regulators of the CRPC pathogenesis. The present review provides an overview of the relevant literature pertaining to the mechanisms governing the molecular acquisition of castration resistance in prostate cancer, providing a foundation for future, targeted therapeutic efforts.

Basics of androgen synthesis and action

Androgens are essential sex steroid hormones for both sexes. Testosterone (T) is the predominant androgen in males, while in adult females, T concentrations are about 15-fold lower and androgen precursors are converted to estrogens. T is produced primarily in testicular Leydig cells in men, while in women precursors are biosynthesised in the adrenal cortex and ovaries and converted into T in the periphery. The biosynthesis of T occurs via a series of enzymatic reactions in steroidogenic organs. Notably, the more potent androgen, dihydrotestosterone, may be synthesized from T in the classic pathway, however, alternate metabolic pathways also exist. The classic action of androgens on target organs is mediated through the androgen receptor, which regulates nuclear receptor gene transcription. However, the androgen-androgen receptor complex may also interact directly with membrane proteins or signaling molecules to exert more rapid effects. This review summarizes the current knowledge of androgen biosynthesis, mechanisms of action and endocrine effects in human biology, and relates these effects to respective human congenital and acquired disorders.

High intratumoral dihydrotestosterone is associated with antiandrogen resistance in VCaP prostate cancer xenografts in castrated mice

Antiandrogen treatment resistance is a major clinical concern in castration-resistant prostate cancer (CRPC) treatment. Using xenografts of VCaP cells we showed that growth of antiandrogen resistant CRPC tumors were characterized by a higher intratumor dihydrotestosterone (DHT) concentration than that of treatment responsive tumors. Furthermore, the slow tumor growth after adrenalectomy was associated with a low intratumor DHT concentration. Reactivation of androgen signaling in enzalutamide-resistant tumors was further shown by the expression of several androgen-dependent genes. The data indicate that intratumor DHT concentration and expression of several androgen-dependent genes in CRPC lesions is an indication of enzalutamide treatment resistance and an indication of the need for further androgen blockade. The presence of an androgen synthesis, independent of CYP17A1 activity, has been shown to exist in prostate cancer cells, and thus, novel androgen synthesis inhibitors are needed for the treatment of enzalutamide-resistant CRPC tumors that do not respond to abiraterone.

Cabazitaxel suppresses the proliferation and promotes the apoptosis and radiosensitivity of castration-resistant prostate cancer cells by inhibiting PI3K/AKT pathway

BACKGROUND

Cabazitaxel has been applied to the treatment of castration-resistant prostate cancer (CRPC), but the molecular mechanism remained to be fully understood.

METHODS

After treatment with Cabazitaxel alone or in combination with ionizing radiation (IR), CRPC cell viability, proliferation and apoptosis were determined by Cell Counting Kit-8 (CCK-8) assay, colony formation, and flow cytometry, respectively. Tumor volume was measured after the establishment of animal xenograft model. Relative expressions of proteins related to apoptosis (B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), and cleaved caspase 3) and phosphoinositide 3-kinase (PI3K)/AKT pathway were measured by Western blot, and the phosphorylated-PI3K/PI3K and p-AKT/AKT ratios were determined as well.

RESULTS

Cell viability and proliferation were suppressed, and apoptosis was promoted in CRPC cells after Cabazitaxel treatment alone, accompanied with upregulated expressions of Bax and cleaved caspase 3 and downregulated Bcl-2 expression. Also, a single treatment with Cabazitaxel resulted in suppression of PI3K/AKT pathway activation, along with downregulated expressions of p-PI3K and p-AKT and a reduced ratio of p-PI3K/PI3K to p-AKT/AKT. Meanwhile, Cabazitaxel enhanced the effects of IR on suppressing survival and promoting apoptosis in CRPC cells through downregulating Bcl-2 and upregulating Bax and cleaved caspase 3. However, Cabazitaxel suppressed IR-induced PI3K/AKT pathway activation via downregulating p-PI3K and p-AKT, leading to a reduced ratio of p-PI3K/PI3K to p-AKT/AKT. Furthermore, Cabazitaxel further promoted the effects of IR on suppressing tumor growth in vivo.

CONCLUSION

Cabazitaxel inhibited the proliferation and promoted the apoptosis and radiosensitivity of CRPC cells, which is related to the suppression of PI3K/AKT pathway, providing a therapeutic method for CRPC in clinical practice.

Gut bacteria enable prostate cancer growth

[Figure: see text].

The effects of selected inhibitors on human fetal adrenal steroidogenesis differs under basal and ACTH-stimulated conditions

BACKGROUND

Disordered fetal adrenal steroidogenesis can cause marked clinical effects including virilization of female fetuses. In postnatal life, adrenal disorders can be life-threatening due to the risk of adrenal crisis and must be carefully managed. However, testing explicit adrenal steroidogenic inhibitory effects of therapeutic drugs is challenging due to species-specific characteristics, and particularly the impact of adrenocorticotropic hormone (ACTH) stimulation on drugs targeting steroidogenesis has not previously been examined in human adrenal tissue. Therefore, this study aimed to examine the effects of selected steroidogenic inhibitors on human fetal adrenal (HFA) steroid hormone production under basal and ACTH-stimulated conditions.

METHODS

This study used an established HFA ex vivo culture model to examine treatment effects in 78 adrenals from 50 human fetuses (gestational weeks 8-12). Inhibitors were selected to affect enzymes critical for different steps in classic adrenal steroidogenic pathways, including CYP17A1 (Abiraterone acetate), CYP11B1/2 (Osilodrostat), and a suggested CYP21A2 inhibitor (Efavirenz). Treatment effects were examined under basal and ACTH-stimulated conditions in tissue from the same fetus and determined by quantifying the secretion of adrenal steroids in the culture media using liquid chromatography-tandem mass spectrometry. Statistical analysis was performed on ln-transformed data using one-way ANOVA for repeated measures followed by Tukey's multiple comparisons test.

RESULTS

Treatment with Abiraterone acetate and Osilodrostat resulted in potent inhibition of CYP17A1 and CYP11B1/2, respectively, while treatment with Efavirenz reduced testosterone secretion under basal conditions. ACTH-stimulation affected the inhibitory effects of all investigated drugs. Thus, treatment effects of Abiraterone acetate were more pronounced under stimulated conditions, while Efavirenz treatment caused a non-specific inhibition on steroidogenesis. ACTH-stimulation prevented the Osilodrostat-mediated CYP11B1 inhibition observed under basal conditions.

CONCLUSIONS

Our results show that the effects of steroidogenic inhibitors differ under basal and ACTH-stimulated conditions in the HFA ex vivo culture model. This could suggest that in vivo effects of therapeutic drugs targeting steroidogenesis may vary in conditions where patients have suppressed or high ACTH levels, respectively. This study further demonstrates that ex vivo cultured HFAs can be used to evaluate steroidogenic inhibitors and thereby provide novel information about the local effects of existing and emerging drugs that targets steroidogenesis.

Pharmacokinetic studies of [68 Ga]Ga-PSMA-11 in patients with biochemical recurrence of prostate cancer: detection, differences in temporal distribution and kinetic modelling by tissue type

Purpose

[⁶⁸ Ga]Ga-PSMA-11 is a promising radiopharmaceutical for detecting tumour lesions in prostate cancer, but knowledge of the pharmacokinetics is limited. Dynamic PET-CT was performed to investigate the tumour detection and differences in temporal distribution, as well as in kinetic modelling of [⁶⁸ Ga]Ga-PSMA-11 by tissue type.

Methods

Dynamic PET-CT over the lower abdomen and static whole-body PET-CT 80–90 min p.i. from 142 patients with biochemical recurrence were retrospectively analysed. Detection rates were compared to PSA levels. Average time-activity curves were calculated from tumour lesions and normal tissue. A three-compartment model and non-compartment model were used to calculate tumour kinetics.

Results

Overall detection rate was 70.42%, and in patients with PSA > 0.4 ng/mL 76.67%. All tumour lesions presented the steepest standardised uptake value (SUV) incline in the first 7–8 min before decreasing to different degrees. Normal tissue presented with a low uptake, except for the bladder, which accumulated activity the steepest 15–16 min. p.i.. While all tumour lesions continuously increased, bone metastases showed the steepest decline, resulting in a significantly lower SUV than lymph node metastases (60 and 80–90 min). Transport rate from the blood and tracer binding and internalisation rate were lower in bone metastases. Heterogeneity (fractal dimension) and vascular density were significantly lower in bone metastases.

Conclusion

Even at low PSA between 0.51 and 0.99 ng/mL, detection rate was 57%. Dynamic imaging showed a time window in the first 10 min where tumour uptake is high, but no bladder activity is measured, aiding accuracy in distinction of local recurrence. Kinetic modelling provided additional information for tumour characterisation by tissue type.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05420-1.

A quantitative analysis of total and free 11-oxygenated androgens and its application to human serum and plasma specimens using liquid-chromatography tandem mass spectrometry

Bioactive 11-oxygenated C₁₉ adrenal-derived steroids (11-oxy C₁₉) are potentially relevant in diverse endocrine and metabolic contexts. We report the development and validation of a liquid chromatography electrospray ionization tandem mass spectrometric method (LC-ESI-MS/MS) for the simultaneous quantification of seven 11-oxy C₁₉ using 200 µL of plasma or serum. Sample preparation involved chemical derivatization using hydroxylamine after liquid-liquid extraction to improve specificity and sensitivity. The method allowed the quantitation of total 11-oxy C₁₉ (free + sulfate and glucuronide conjugates) following enzymatic hydrolysis. This included the abundant precursor 11-hydroxyandrostenedione (11OHA4) and the most potent androgenic derivatives 11-keto-testosterone (11KT) and 11-keto-dihydrotestosterone (11KDHT), their abundant metabolites 11-hydroxyandrosterone (11OHAST) and 11-keto-androsterone (11KAST) potentially feeding back into the pool of potent androgens, in addition to 11-keto-androstenedione (11KA4) and 11-hydroxytestosterone (11OHT). Stable isotopes were used as internal standards, and calibrators and quality controls were prepared in the same matrix as the study samples. Performance was validated against the Food and Drug Administration Criteria. The method was sensitive with lower limit of quantification (LLOQ) values of 10 and 20 pg/mL for free and total 11-oxy C₁₉, respectively. The applicability was demonstrated in men and women adult donors that showed sex-differences. All steroids were quantified well above LLOQ, except 11KDHT that remained undetectable suggesting interfering endogenous molecules present in non-derivatized samples in which a peak was observed. By providing accurate and reliable quantitative data, this method will permit to evaluate how profiling of 11-oxy C₁₉ will be most informative as diagnostic, prognostic and/or theranostic tools.

Gut feelings about bacterial steroid-17,20-desmolase

Advances in technology are only beginning to reveal the complex interactions between hosts and their resident microbiota that have co-evolved over centuries. In this review, we present compelling evidence that implicates the host-associated microbiome in the generation of 11β-hydroxyandrostenedione, leading to the formation of potent 11-oxy-androgens. Microbial steroid-17,20-desmolase cleaves the side-chain of glucocorticoids (GC), including cortisol (and its derivatives of cortisone, 5α-dihydrocortisol, and also (allo)- 3α, 5α-tetrahydrocortisol, but not 3α-5β-tetrahydrocortisol) and drugs (prednisone and dexamethasone). In addition to side-chain cleavage, we discuss the gut microbiome's robust potential to transform a myriad of steroids, mirroring much of the host's metabolism. We also explore the overlooked role of intestinal steroidogenesis and efflux pumps as a potential route for GC transport into the gut. Lastly, we propose several health implications from microbial steroid-17,20-desmolase function, including aberrant mineralocorticoid, GC, and androgen receptor signaling in colonocytes, immune cells, and prostate cells, which may exacerbate disease states.

Determination of Intraprostatic and Intratesticular Androgens

Androgens represent the main hormones responsible for maintaining hormonal balance and function in the prostate and testis. As they are involved in prostate and testicular carcinogenesis, more detailed information of their active concentration at the site of action is required. Since the introduction of the term intracrinology as the local formation of active steroid hormones from inactive precursors of the adrenal gland, mainly dehydroepiandrosterone (DHEA) and DHEA-S, it is evident that blood circulating levels of sex steroid hormones need not reflect their actual concentrations in the tissue. Here, we review and critically evaluate available methods for the analysis of human intraprostatic and intratesticular steroid concentrations. Since analytical approaches have much in common in both tissues, we discuss them together. Preanalytical steps, including various techniques for separation of the analytes, are compared, followed by the end-point measurement. Advantages and disadvantages of chromatography-mass spectrometry (LC-MS, GC-MS), immunoanalytical methods (IA), and hybrid (LC-IA) are discussed. Finally, the clinical information value of the determined steroid hormones is evaluated concerning differentiating between patients with cancer or benign hyperplasia and between patients with different degrees of infertility. Adrenal-derived 11-oxygenated androgens are mentioned as perspective prognostic markers for these purposes.

Dual targeting of EZH2 and androgen receptor as a novel therapy for castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) emerges after androgen withdrawal therapy and remains incurable due to the lack of effective treatment protocols. Treatment with enzalutamide, a second generation androgen receptor (AR) antagonist, offers an initial response followed by drug resistance and tumor relapse. Enhancer of zeste homolog 2 (EZH2), a member of PRC2 complex, is an important target that acts as a coactivator of AR-mediated gene suppression whose oncogenic activity increases during castration. We hypothesize that dual targeting of EZH2 and AR could be highly effective in CRPC treatment. The present study aimed to examine the effectiveness of combination using EZH2 inhibitor GSK126 with antiandrogen enzalutamide in the treatment of CRPC cells. Treatment of 22Rv1 and C42B CRPC cells with a combination of GSK126 and enzalutamide led to synergistic inhibition of cell proliferation, cell cycle arrest and marked increase in cell death. Mechanistically, this combination treatment significantly reduced expression of AR and AR-v7, decrease in PSA and Akt activity, diminution of EZH2 and other members of PCR2 complex including SUZ12 and EED, with simultaneous loss of H3K27 trimethylation and dissociation between AR and PRC2 complex members compared to individual treatment. This study provides preclinical proof-of-concept that combined treatment of EZH2 inhibitor with AR antagonist results in synergistic anticancer effects opening new possibilities for treatment of CRPC tumors.

Association Between CYP17A1, CYB5A Polymorphisms and Efficacy of Abiraterone Acetate/Prednisone Treatment in Castration-Resistant Prostate Cancer Patients

PURPOSE

The purpose of this study was to investigate the association between single nucleotide polymorphisms (SNPs) of CYP17A1, CYB5A and the efficacy of abiraterone acetate treatment in patients with castration-resistant prostate cancer (CRPC).

PATIENTS AND METHODS

Data were collected from 58 CRPC patients who had been treated with abiraterone acetate/prednisone (AA/P). The SNPs rs743572 and rs10883783 on CYP17A1 and SNPs rs1790834 and rs1790858 on CYB5A were assayed, and their relationship with prostate-specific antigen (PSA) response in patients after AA/P treatment, overall survival (OS) and progression-free survival (PFS) were analyzed by logistic regression, Cox regression, Kaplan-Meier and Log rank analyses.

RESULTS

The SNP rs1790834 on CYB5A showed significant association with PSA response in CRPC patients treated with AA/P (P < 0.05), but rs743572, rs10883783 and rs1790858 did not. The rs1790834 variant significantly decreased both PFS and OS (P < 0.05).

CONCLUSION

The CYB5A rs790834 genotype is a novel SNP related to CRPC and may be used as a biomarker for CRPC treatment.