Dihydrotestosterone synthesis pathways from inactive androgen 5α-androstane-3β,17β-diol in prostate cancer cells: Inhibition of intratumoural 3β-hydroxysteroid dehydrogenase activities by abiraterone

Androgen receptor pathway inhibitors and drug-drug interactions in prostate cancer

Prostate cancer represents a major global health challenge, necessitating efficacious therapeutic strategies. Androgen receptor pathway inhibitors (ARPIs) have become central to prostate cancer treatment, demonstrating significant effectiveness in both metastatic and non-metastatic contexts. Abiraterone acetate, by inhibiting androgen synthesis, deprives cancer cells androgens necessary for growth, while second-generation androgen receptor (AR) antagonists disrupt AR signaling by blocking AR binding, thereby impeding tumor progression. Given the predominance of prostate cancer in the elderly, who often present with multiple comorbidities requiring complex pharmacological regimens, the potential for drug-drug interactions with ARPIs is a critical concern. These interactions, particularly through pathways like CYP2D6 inhibition by abiraterone and CYP3A4 induction by enzalutamide and apalutamide, necessitate a thorough understanding to optimize therapeutic outcomes and minimize adverse effects. This review aims to delineate the efficacy of ARPIs in prostate cancer management and elucidate their interaction with common medications, highlighting the importance of vigilant drug management to optimize patient care.

CYP7B1 as a Biomarker for Prostate Cancer Risk and Progression: Metabolic and Oncogenic Signatures (Diagnostic Immunohistochemistry Analysis by Tissue Microarray in Prostate Cancer Patients-Diamond Study)

We aimed to analyze the association between CYP7B1 and prostate cancer, along with its association with proteins involved in cancer and metabolic processes. A retrospective analysis was performed on 390 patients with prostate cancer (PC) or benign prostatic hyperplasia (BPH). We investigated the interactions between CYP7B1 expression and proteins associated with PC and metabolic processes, followed by an analysis of the risk of biochemical recurrence based on CYP7B1 expression. Of the 139 patients with elevated CYP7B1 expression, 92.8% had prostate cancer. Overall, no increased risk of biochemical recurrence was associated with CYP7B1 expression. However, in a non-diabetic subgroup analysis, higher CYP7B1 expression indicated a higher risk of biochemical recurrence, with an HR of 1.78 (CI: 1.0-3.2, p = 0.05). PC is associated with elevated CYP7B1 expression. In a subgroup analysis of non-diabetic patients, elevated CYP7B1 expression was associated with an increased risk of biochemical recurrence, suggesting increased cancer aggressiveness.

Identification of blood metabolites associated with risk of Alzheimer's disease by integrating genomics and metabolomics data

Specific metabolites have been reported to be potentially associated with Alzheimer's disease (AD) risk. However, the comprehensive understanding of roles of metabolite biomarkers in AD etiology remains elusive. We performed a large AD metabolome-wide association study (MWAS) by developing blood metabolite genetic prediction models. We evaluated associations between genetically predicted levels of metabolites and AD risk in 39,106 clinically diagnosed AD cases, 46,828 proxy AD and related dementia (proxy-ADD) cases, and 401,577 controls. We further conducted analyses to determine microbiome features associated with the detected metabolites and characterize associations between predicted microbiome feature levels and AD risk. We identified fourteen metabolites showing an association with AD risk. Five microbiome features were further identified to be potentially related to associations of five of the metabolites. Our study provides new insights into the etiology of AD that involves blood metabolites and gut microbiome, which warrants further investigation.

Estrogen receptor β and treatment with a phytoestrogen are associated with inhibition of nuclear translocation of EGFR in the prostate

Knockout of ERβ in the mouse leads to nuclear expression of epidermal growth factor receptor (EGFR) in the prostate. To examine whether ERβ plays a similar role in the human prostate, we used four cohorts of men: 1) a Swedish cohort of normal prostates and PCa (prostate cancer) of different Gleason grades; 2) men with benign prostatic hyperplasia (BPH) treated with the 5α-reductase inhibitor, finasteride, and finasteride together with the ERβ agonists, soy isoflavones; 3) men with PCa above Gleason grade 4 (GG4), treated with ADT (androgen deprivation therapy) and abiraterone (AA), the blocker of androgen synthesis for different durations; and 4) men with GG4 PCa on ADT or ADT with the AR (androgen receptor) blocker, enzalutamide, for 4 mo to 6 mo. In men with BPH, finasteride treatment induced EGFR nuclear expression, but, when finasteride was combined with isoflavones, EGFR remained on the cell membrane. In GG4 patients, blocking of AR for 4 mo to 6 mo resulted in loss of ERβ and PTEN expression and increase in patients with nuclear EGFR from 10 to 40%. In the men with GG4 PCa, blocking of adrenal synthesis of testosterone for 2 mo to 7 mo had the beneficial effect of increasing ERβ expression, but, on treatment longer than 8 mo, ERβ was lost and EGFR moved to the nucleus. Since nuclear EGFR is a predictor of poor outcome in PCa, addition of ERβ agonists together with abiraterone should be considered as a treatment that might sustain expression of ERβ and offer some benefit to patients.

A highly sensitive LC-MS/MS method for the simultaneous quantitation of serum androstane-3α, 17β-diol and androstane-3β, 17β-diol in post-menopausal women

Sensitive and accurate measurement of androstane-3β,17β-diol and androstane-3α,17β-diol in the circulation is important for clinical research and accurate clinical diagnosis. This report describes a highly sensitive, specific, precise and reliable assay for the simultaneous accurate measurement of serum androstane-3α,17β-diol and androstane-3β,17β-diol in postmenopausal women. The LLOQ of 1 pg/mL has been achieved with nicotinic acid derivatization, which is superior to picolinic acid by a factor of 5 to 10 in terms of signal to noise ratio. The difference is attributed to the higher acidity of picolinic acid which forms a more stable intermediate, thus decreasing derivatization efficiency. Potential interference from androstane-3α, 17α-diol, androstane-3β, 17α-diol, and 5-androstenediol has been well separated from the two target diols. The high level of specificity has been determined by well-developed chromatography and ion ratio monitoring. A good linearity in the range of 1 pg/mL to 200 pg/mL (0.03 pg to 6 pg on column) was obtained for both compounds at R > 0.998. The bias and coefficients of variation of all the QC levels are within the range of 10% while the recovery in both charcoal-stripped and unstripped human serum is around 85%. The matrix effect was evaluated and the results well met the acceptance criteria according to the guidelines of bioanalytical method development and validation. Using this newly developed method, the concentrations of both androstane-3α,17β diol and androstane-3β,17β diol were measured in normal postmenopausal serum, where the concentrations range from 2 pg/mL to 32 pg/mL for androstane-3α,17β diol and from 1 pg/mL to 10 pg/mL for androstane-3β,17β diol, respectively.

Simultaneous determination of dihydrotestosterone and its metabolites in mouse sera by LC-MS/MS with chemical derivatization

Androgens play a vital role in prostate cancer development, and their elimination and blockade are essential in the disease management. DHT is the key ligand for androgen receptor (AR) in the prostate. It is locally synthesized from testosterone. In the prostate, DHT is predominantly metabolized to α-diol and β-diol. Recent studies indicate that impaired DHT catabolism is associated with prostate cancer, signifying the necessity of a sensitive quantitative method for the determination of DHT and its metabolites. In this work, an LC-MS/MS method for the simultaneous quantification of DHT and its metabolites was developed and validated. Steroid-free sera were prepared and used for the preparation of sera calibrators and quality controls (QCs). DHT and its metabolites along with their respective stable heavy isotope labeled analytes representing internal standards were first extracted with methyl tertiary-butyl ether (MTBE) and derivatized with picolinic acid (PA). The derivatized analytes were then extracted again with MTBE, dried under nitrogen and reconstituted in the mobile phase (80% methanol and 0.2% formic acid in water). Baseline chromatographic separation of the derivatized analytes was achieved isocratically on XTerra C18 column (2.1 × 100 mm) using the mobile phase at a flow rate of 0.25 mL/min. Quantitation was performed using multiple-reaction-monitoring mode with positive electrospray ionization. The method has calibration ranges from 0.0500 ng/mL to 50.0 ng/mL for DHT and its two metabolites with acceptable assay precision, accuracy, recovery, and matrix factor. It was applied to the determination of DHT and its metabolites in an animal study.