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1.
J Steroid Biochem Mol Biol ; 241: 106499, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604378

RESUMO

The androgen receptor (AR) is a steroid activated transcription factor which recognizes DNA motifs resembling inverted repeats of a conserved 5'-AGAACA-3'-like hexanucleotides separated by a three-nucleotide spacer from a similar, but less conserved hexanucleotide. Here, we report the structures of the human AR DNA binding domain (DBD) bound to two natural AREs (C3 and MTV) in head-to-head dimer conformations, diffracting at 2.05 Šand 2.25 Å, respectively. These structures help to explain the impact of androgen insensitivity mutations on the structure integrity, DNA binding and DBD dimerization. The binding affinity of the AR DBD to different DNA motifs were measured by the BioLayer Interferometry (BLI) and further validated by Molecular Dynamics (MD) simulations. This shows that the high binding affinity of the first DBD to the upstream 5'-AGAACA-3' motif induces the cooperative binding of the second DBD to the second hexanucleotide. Our data indicate identical interaction of the DBDs to the upstream hexanucleotides, while forming an induced closer contact of the second DBD on the non-canonical hexanucleotides. The variation in binding between the DBD monomers are the result of differences in DNA occupancy, protein-protein interactions, DNA binding affinity, and DNA binding energy profiles. We propose this has functional consequences.

2.
Protein Sci ; 33(4): e4940, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38511482

RESUMO

Estrogen receptor α is commonly used in synthetic biology to control the activity of genome editing tools. The activating ligands, estrogens, however, interfere with various cellular processes, thereby limiting the applicability of this receptor. Altering its ligand preference to chemicals of choice solves this hurdle but requires adaptation of unspecified ligand-interacting residues. Here, we provide a solution by combining rational protein design with multi-site-directed mutagenesis and directed evolution of stably integrated variants in Saccharomyces cerevisiae. This method yielded an estrogen receptor variant, named TERRA, that lost its estrogen responsiveness and became activated by tamoxifen, an anti-estrogenic drug used for breast cancer treatment. This tamoxifen preference of TERRA was maintained in mammalian cells and mice, even when fused to Cre recombinase, expanding the mammalian synthetic biology toolbox. Not only is our platform transferable to engineer ligand preference of any steroid receptor, it can also profile drug-resistance landscapes for steroid receptor-targeted therapies.


Assuntos
Estradiol , Receptor alfa de Estrogênio , Animais , Camundongos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/metabolismo , Estradiol/química , Estradiol/metabolismo , Ligantes , Tamoxifeno/farmacologia , Tamoxifeno/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/química , Receptores de Estrogênio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Mamíferos
3.
J Steroid Biochem Mol Biol ; 239: 106476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38311010

RESUMO

A new chemical scaffold with antagonistic activity towards the androgen receptor (AR) was identified. The parent compound, (3-Methoxy-N-[1-methyl-2-(4-phenyl-1-piperazinyl)-2-(2-thienyl)ethyl]benzamide) referred to as MEL-6, binds in the ligand binding pocket of AR and induces an antagonistic conformation of the ligand binding domain, even in presence of the antagonist-to-agonist switch mutations W741C, T877A and F876L-T877A. MEL-6 has antiproliferative effects on several AR positive prostate cancer cell lines. We further identified AR as the specific target of MEL-6 since it demonstrates little effect on other steroid receptors. In LNCaP cells it also inhibits the androgen-regulated transcriptome. These findings identify MEL-6 as a promising candidate for treatment of patients with prostate tumors that have become resistant to current clinically used AR antagonists. Analytical studies on the chemical composition of MEL-6 identified the presence of four isomers (two enantiomeric pairs), among which one isomer is responsible for the antiandrogenic activity. We therefore developed a synthetic route towards the selective preparation of the active enantiomeric pair. Various MEL-6-like analogues had improved metabolic stability while maintaining antiandrogenic activity. Metabolite identification of MEL-6 derivatives pinpointed N-dealkylation of the piperazine as the main mode for inactivation by liver enzymes. For further structural optimization, MEL-6 derivatives were purchased or synthesized having alterations on the N-phenyl group of the piperazine, the benzoyl group and additionally substituting the thiophen-2-yl ring of MEL-6 to a phenyl ring. This optimization process resulted in compound 12b with sustained AR inhibition and a 4-fold increased half-life due to the 1-(5-chloro-2-methylphenyl)-piperazine substitution, thienyl-to-phenyl substitution and chloro in para-position of the benzoyl group.


Assuntos
Antagonistas de Receptores de Andrógenos , Neoplasias da Próstata , Masculino , Humanos , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/química , Ligantes , Receptores Androgênicos/metabolismo , Neoplasias da Próstata/metabolismo , Androgênios , Piperazinas/farmacologia , Linhagem Celular Tumoral , Antagonistas de Androgênios/farmacologia
4.
J Transl Med ; 22(1): 71, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238739

RESUMO

The androgen receptor (AR) is a crucial player in various aspects of male reproduction and has been associated with the development and progression of prostate cancer (PCa). Therefore, the protein is the linchpin of current PCa therapies. Despite great research efforts, the AR signaling pathway has still not been deciphered, and the emergence of resistance is still the biggest problem in PCa treatment. To discuss the latest developments in AR research, the "1st International Androgen Receptor Symposium" offered a forum for the exchange of clinical and scientific innovations around the role of the AR in prostate cancer (PCa) and to stimulate new collaborative interactions among leading scientists from basic, translational, and clinical research. The symposium included three sessions covering preclinical studies, prognostic and diagnostic biomarkers, and ongoing prostate cancer clinical trials. In addition, a panel discussion about the future direction of androgen deprivation therapy and anti-AR therapy in PCa was conducted. Therefore, the newest insights and developments in therapeutic strategies and biomarkers are discussed in this report.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Receptores Androgênicos/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Antagonistas de Androgênios/uso terapêutico , Transdução de Sinais , Biomarcadores
6.
EBioMedicine ; 97: 104817, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804569

RESUMO

BACKGROUND: Prostate cancer (PCa) patients treated with androgen deprivation therapy (ADT) have an increased fracture risk. Exploring biomarkers for early bone loss detection is of great interest. METHODS: Pre-planned substudy of the ARNEO-trial (NCT03080116): a double blind, randomised, placebo-controlled phase 2 trial performed in high-risk PCa patients without bone metastases between March 2019 and April 2021. Patients were 1:1 randomised to treatment with gonadotropin-releasing hormone antagonist (degarelix) + androgen receptor signalling inhibitor (ARSI; apalutamide) versus degarelix + matching placebo for 12 weeks prior to prostatectomy. Before and following ADT, serum and 24-h urinary samples were collected. Primary endpoints were changes in calcium-phosphate homeostasis and bone biomarkers. FINDINGS: Of the 89 randomised patients, 43 in the degarelix + apalutamide and 44 patients in the degarelix + placebo group were included in this substudy. Serum corrected calcium levels increased similarly in both treatment arms (mean difference +0.04 mmol/L, 95% confidence interval, 0.02; 0.06), and parathyroid hormone and 1,25-dihydroxyvitamin D3 levels decreased. Bone resorption markers increased, and stable calcium isotope ratios reflecting net bone mineral balance decreased in serum and urine similarly in both groups. INTERPRETATION: This exploratory substudy suggests that 12 weeks of ADT in non-metastatic PCa patients results in early bone loss. Additional treatment with ARSI does not seem to more negatively influence bone loss in the early phase. Future studies should address if these early biomarkers are able to predict fracture risk, and can be implemented in clinical practice for follow-up of bone health in PCa patients under ADT. FUNDING: Research Foundation Flanders; KU Leuven; University-Hospitals-Leuven.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Masculino , Humanos , Antagonistas de Androgênios/efeitos adversos , Neoplasias da Próstata/patologia , Androgênios , Receptores Androgênicos , Cálcio , Antagonistas de Receptores de Andrógenos/efeitos adversos , Minerais/uso terapêutico , Homeostase , Biomarcadores
7.
Front Oncol ; 13: 1265812, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810962

RESUMO

Prostate cancer (PCa) is the most common cancer in men worldwide. Despite better and more intensive treatment options in earlier disease stages, a large subset of patients still progress to metastatic castration-resistant PCa (mCRPC). Recently, poly-(ADP-ribose)-polymerase (PARP)-inhibitors have been introduced in this setting. The TALAPRO-2 and PROpel trials both showed a marked benefit of PARPi in combination with an androgen receptor signaling inhibitor (ARSI), compared with an ARSI alone in both the homologous recombination repair (HRR)-mutated, as well as in the HRR-non-mutated subgroup. In this review, we present a comprehensive overview of how maximal AR-blockade via an ARSI in combination with a PARPi has a synergistic effect at the molecular level, leading to synthetic lethality in both HRR-mutated and HRR-non-mutated PCa patients. PARP2 is known to be a cofactor of the AR complex, needed for decompacting the chromatin and start of transcription of AR target genes (including HRR genes). The inhibition of PARP thus reinforces the effect of an ARSI. The deep androgen deprivation caused by combining androgen deprivation therapy (ADT) with an ARSI, induces an HRR-like deficient state, often referred to as "BRCA-ness". Further, PARPi will prevent the repair of single-strand DNA breaks, leading to the accumulation of DNA double-strand breaks (DSBs). Due to the induced HRR-deficient state, DSBs cannot be repaired, leading to apoptosis.

8.
Mol Cancer Ther ; 22(10): 1166-1181, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37486978

RESUMO

Prostate cancers adapt to androgen receptor (AR) pathway inhibitors and progress to castration resistance due to ongoing AR expression and function. To counter this, we developed a new approach to modulate the AR and inhibit castration-resistant prostate cancer (CRPC) using multivalent peptoid conjugates (MPC) that contain multiple copies of the AR-targeting ligand ethisterone attached to a peptidomimetic scaffold. Here, we investigated the antitumor effects of compound MPC309, a trivalent display of ethisterone conjugated to a peptoid oligomer backbone that binds to the AR with nanomolar affinity. MPC309 exhibited potent antiproliferative effects on various enzalutamide-resistant prostate cancer models, including those with AR splice variants, ligand-binding mutations, and noncanonical AR gene expression programs, as well as mouse prostate organoids harboring defined genetic alterations that mimic lethal human prostate cancer subtypes. MPC309 is taken up by cells through macropinocytosis, an endocytic process more prevalent in cancer cells than in normal ones, thus providing an opportunity to target tumors selectively. MPC309 triggers a distinct AR transcriptome compared with DHT and enzalutamide, a clinically used antiandrogen. Specifically, MPC309 enhances the expression of differentiation genes while reducing the expression of genes needed for cell division and metabolism. Mechanistically, MPC309 increases AR chromatin occupancy and alters AR interactions with coregulatory proteins in a pattern distinct from DHT. In xenograft studies, MPC309 produced significantly greater tumor suppression than enzalutamide. Altogether, MPC309 represents a promising new AR modulator that can combat resistant disease by promoting an AR antiproliferative gene expression program.


Assuntos
Peptoides , Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Animais , Camundongos , Humanos , Receptores Androgênicos/metabolismo , Peptoides/farmacologia , Ligantes , Etisterona/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias da Próstata/patologia , Nitrilas/farmacologia , Antagonistas de Receptores de Andrógenos/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo
9.
J Bone Miner Res ; 38(10): 1497-1508, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37222072

RESUMO

Transgender youth increasingly present at pediatric gender services. Some of them receive long-term puberty suppression with gonadotropin-releasing hormone analogues (GnRHa) before starting gender-affirming hormones (GAH). The impact of GnRHa use started in early puberty on bone composition and bone mass accrual is unexplored. It is furthermore unclear whether subsequent GAH fully restore GnRHa effects and whether the timing of GAH introduction matters. To answer these questions, we developed a mouse model mimicking the clinical strategy applied in trans boys. Prepubertal 4-week-old female mice were treated with GnRHa alone or with GnRHa supplemented with testosterone (T) from 6 weeks (early puberty) or 8 weeks (late puberty) onward. Outcomes were analyzed at 16 weeks and compared with untreated mice of both sexes. GnRHa markedly increased total body fat mass, decreased lean body mass, and had a modest negative impact on grip strength. Both early and late T administration shaped body composition to adult male levels, whereas grip strength was restored to female values. GnRHa-treated animals showed lower trabecular bone volume and reduced cortical bone mass and strength. These changes were reversed by T to female levels (cortical bone mass and strength) irrespective of the time of administration or even fully up to adult male control values (trabecular parameters) in case of earlier T start. The lower bone mass in GnRHa-treated mice was associated with increased bone marrow adiposity, also reversed by T. In conclusion, prolonged GnRHa use started in prepubertal female mice modifies body composition toward more fat and less lean mass and impairs bone mass acquisition and strength. Subsequent T administration counteracts GnRHa impact on these parameters, shaping body composition and trabecular parameters to male values while restoring cortical bone architecture and strength up to female but not male control levels. These findings could help guide clinical strategies in transgender care. © 2023 American Society for Bone and Mineral Research (ASBMR).

10.
Res Sq ; 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37034758

RESUMO

Genetic variation at the 19q13.3 KLK locus is linked with prostate cancer susceptibility. The non-synonymous KLK3 SNP, rs17632542 (c.536T>C; Ile163Thr-substitution in PSA) is associated with reduced prostate cancer risk, however, the functional relevance is unknown. Here, we identify that the SNP variant-induced change in PSA biochemical activity as a previously undescribed function mediating prostate cancer pathogenesis. The 'Thr' PSA variant led to small subcutaneous tumours, supporting reduced prostate cancer risk. However, 'Thr' PSA also displayed higher metastatic potential with pronounced osteolytic activity in an experimental metastasis in-vivo model. Biochemical characterization of this PSA variant demonstrated markedly reduced proteolytic activity that correlated with differences in in-vivo tumour burden. The SNP is associated with increased risk for aggressive disease and prostate cancer-specific mortality in three independent cohorts, highlighting its critical function in mediating metastasis. Carriers of this SNP allele had reduced serum total PSA and a higher free/total PSA ratio that could contribute to late biopsy decisions and delay in diagnosis. Our results provide a molecular explanation for the prominent 19q13.3 KLK locus, rs17632542 SNP, association with a spectrum of prostate cancer clinical outcomes.

11.
Dis Model Mech ; 16(6)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37102205

RESUMO

Female bias is highly prevalent in conditions such as adrenal cortex hyperplasia and neoplasia, but the reasons behind this phenomenon are poorly understood. In this study, we show that overexpression of the secreted WNT agonist R-spondin 1 (RSPO1) leads to ectopic activation of WNT/ß-catenin signaling and causes sex-specific adrenocortical hyperplasia in mice. Although female adrenals show ectopic proliferation, male adrenals display excessive immune system activation and cortical thinning. Using a combination of genetic manipulations and hormonal treatment, we show that gonadal androgens suppress ectopic proliferation in the adrenal cortex and determine the selective regulation of the WNT-related genes Axin2 and Wnt4. Notably, genetic removal of androgen receptor (AR) from adrenocortical cells restores the mitogenic effect of WNT/ß-catenin signaling. This is the first demonstration that AR activity in the adrenal cortex determines susceptibility to canonical WNT signaling-induced hyperplasia.


Assuntos
Receptores Androgênicos , Via de Sinalização Wnt , Masculino , Camundongos , Feminino , Animais , Receptores Androgênicos/genética , beta Catenina/metabolismo , Hiperplasia , Proteínas Wnt/genética
12.
Protein Sci ; 32(4): e4599, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36806291

RESUMO

We report the discovery of the androgen receptor missense mutation V770D, that was found in two sisters suffering from complete androgen insensitivity. Experimental validation of AR V770 variants demonstrated that AR V770D was transcriptionally inactive due to the inability to dimerize and a reduced ligand binding affinity. The more conservative AR V770A variant showed a dimerization defect at low levels of DHT with a partial recovery of the transcriptional activity and of the receptor's ability to dimerize when increasing the DHT levels. With V770 located outside of the proposed LBD dimerization interface of the AR LBD homodimer crystal structure, the effects of the V770A mutation on AR dimerization were unexpected. We therefore explored whether the AR LBD dimerization interface would be better described by an alternative dimerization mode based on available human homodimeric LBD crystal structures of other nuclear receptors. Superposition of the monomeric AR LBD in the homodimeric crystal structures of GR, PR, ER, CAR, TRß, and HNF-4α showed that the GR-like LBD dimer model was energetically the most stable. Moreover, V770 was a key energy residue in the GR-like LBD dimer while it was not involved in the stabilization of the AR LBD homodimer according to the crystal structure. Additionally, the observation that 4 AIS mutations impacted the stability of the AR LBD dimer while 16 mutations affected the GR-like LBD dimer, suggested that the AR LBD dimer crystal is a snapshot of a breathing AR LBD homodimer that can transition into the GR-like LBD dimer model.


Assuntos
Síndrome de Resistência a Andrógenos , Receptores Androgênicos , Masculino , Humanos , Receptores Androgênicos/genética , Receptores Androgênicos/química , Síndrome de Resistência a Andrógenos/genética , Ligantes , Ligação Proteica/genética , Mutação de Sentido Incorreto , Mutação
13.
Eur Urol ; 83(6): 508-518, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36167599

RESUMO

BACKGROUND: High-risk prostate cancer (PCa) patients have a high risk of biochemical recurrence and metastatic progression following radical prostatectomy (RP). OBJECTIVE: To determine the efficacy of neoadjuvant degarelix plus apalutamide before RP compared with degarelix with a matching placebo. DESIGN, SETTING, AND PARTICIPANTS: ARNEO was a randomized, placebo-controlled, phase II neoadjuvant trial before RP performed between March 2019 and April 2021. Eligible patients had high-risk PCa and were amenable to RP. INTERVENTION: Patients were randomly assigned at a 1:1 ratio to degarelix (240-80-80 mg) + apalutamide (240 mg/d) versus degarelix + matching placebo for 3 mo followed by RP. Prior to and following neoadjuvant treatment, pelvic 18F-PSMA-1007 positron emission tomography (PET)/magnetic resonance imaging (MRI) was performed. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was the difference in proportions of patients with minimal residual disease (MRD; = residual cancer burden (RCB) ≤0.25 cm3 at final pathology). Secondary endpoints included differences in prostate-specific antigen responses, pathological staging, and change in TNM stage on prostate-specific membrane antigen (PSMA) PET/MRI following hormonal treatment. Biomarkers (immunohistochemical staining on prostate biopsy [PTEN, ERG, Ki67, P53, GR, and PSMA] and PSMA PET/MRI-derived characteristics) associated with pathological response (MRD and RCB) were explored. RESULTS AND LIMITATIONS: Patients were randomized to neoadjuvant degarelix + apalutamide (n = 45) or degarelix + matching placebo (n = 44) for 12 wk and underwent RP. Patients in the degarelix + apalutamide arm achieved a significantly higher rate of MRD than those in the control arm (38% vs 9.1%; relative risk [95% confidence interval] = 4.2 [1.5-11], p = 0.002). Patients with PTEN loss in baseline prostate biopsy attained significantly less MRD (11% vs 43%, p = 0.002) and had a higher RCB at final pathology (1.6 vs 0.40 cm3, p < 0.0001) than patients without PTEN loss. Following neoadjuvant hormonal therapy, PSMA PET-estimated tumor volumes (1.2 vs 2.5 ml, p = 0.01) and maximum standardized uptake value (SUVmax; 4.3 vs 5.7, p = 0.007) were lower in patients with MRD than in patients without MRD. PSMA PET-estimated volume and PSMA PET SUVmax following neoadjuvant treatment correlated significantly with RCB at final pathology (both p < 0.001). CONCLUSIONS: In high-risk PCa patients, neoadjuvant degarelix plus apalutamide prior to RP results in a significantly improved pathological response (MRD and RCB) compared with degarelix alone. Our trial results provide a solid hypothesis-generating basis for neoadjuvant phase 3 trials, which are powered to detect differences in long-term oncological outcome following neoadjuvant androgen receptor signaling inhibitor therapy. PATIENT SUMMARY: In this study, we looked at the difference in pathological responses in high-risk prostate cancer patients treated with degarelix plus apalutamide or degarelix plus matching placebo prior to radical prostatectomy. We demonstrated that patients treated with degarelix plus apalutamide achieved a significantly better tumor response than patients treated with degarelix plus matching placebo. Long-term follow-up is required to determine whether improved pathological outcome translates into better oncological outcomes.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/cirurgia , Terapia Neoadjuvante/métodos , Prostatectomia/métodos , Radioisótopos de Gálio
14.
Mol Cancer Ther ; 21(12): 1823-1834, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36218067

RESUMO

Currently, all clinically used androgen receptor (AR) antagonists target the AR ligand-binding pocket and inhibit T and dihydrotestosterone (DHT) binding. Resistance to these inhibitors in prostate cancer frequently involves AR-dependent mechanisms resulting in a retained AR dependence of the tumor. More effective or alternative AR inhibitors are therefore required to limit progression in these resistant stages. Here, we applied the structural information of the ligand-binding domain (LBD) dimerization interface to screen in silico for inhibitors. A completely new binding site, the Dimerisation Inhibiting Molecules (DIM) pocket, was identified at the LBD dimerization interface. Selection of compounds that fit the DIM pocket via virtual screening identified the DIM20 family of compounds which inhibit AR transactivation and dimerization of the full-length AR as well as the isolated LBDs. Via biolayer interferometry, reversible dose-dependent binding to the LBD was confirmed. While DIM20 does not compete with 3H-DHT for binding in the LBP, it limits the maximal activity of the AR indicative of a noncompetitive binding to the LBD. DIM20 and DIM20.39 specifically inhibit proliferation of AR-positive prostate cancer cell lines, with only marginal effects on AR-negative cell lines such as HEK 293 and PC3. Moreover, combination treatment of DIM compounds with enzalutamide results in synergistic antiproliferative effects which underline the specific mechanism of action of the DIM compounds.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Masculino , Humanos , Receptores Androgênicos/metabolismo , Ligantes , Dimerização , Células HEK293 , Antagonistas de Receptores de Andrógenos/farmacologia , Di-Hidrotestosterona/farmacologia , Di-Hidrotestosterona/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Linhagem Celular Tumoral , Antagonistas de Androgênios/farmacologia
16.
Endocrinology ; 163(9)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35908178

RESUMO

The androgen receptor (AR) plays a central role in the development and maintenance of the male phenotype. The binding of androgens to the receptor induces interactions between the carboxyterminal ligand-binding domain and the highly conserved 23FQNLF27 motif in the aminoterminal domain. The role of these so-called N/C interactions in AR functioning is debated. In vitro assays show that mutating the AR in the 23FQNLF27 motif (called ARNoC) attenuates the AR transactivation of reporter genes, has no effect on ligand binding, but does affect protein-protein interactions with several AR coregulators. To test the in vivo relevance of the N/C interaction, we analyzed the consequences of the genomic introduction of the ARNoC mutation in mice. Surprisingly, the ARNoC/Y mice show a normal male development, with unaffected male anogenital distance and normal accessory sex glands, male circulating androgen levels, body composition, and fertility. The responsiveness of androgen target genes in kidney, prostate, and testes was also unaffected. We thus conclude that the N/C interactions in the AR are not essential for the development of a male phenotype under normal physiological conditions.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Androgênios/farmacologia , Animais , Ligantes , Masculino , Camundongos , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Ativação Transcricional
17.
Rev Endocr Metab Disord ; 23(6): 1173-1208, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35841491

RESUMO

Osteoporosis does not only affect postmenopausal women, but also ageing men. The burden of disease is projected to increase with higher life expectancy both in females and males. Importantly, osteoporotic men remain more often undiagnosed and untreated compared to women. Sex steroid deficiency is associated with bone loss and increased fracture risk, and circulating sex steroid levels have been shown to be associated both with bone mineral density and fracture risk in elderly men. However, in contrast to postmenopausal osteoporosis, the contribution of relatively small decrease of circulating sex steroid concentrations in the ageing male to the development of osteoporosis and related fractures, is probably only minor. In this review we provide several clinical and preclinical arguments in favor of a 'bone threshold' for occurrence of hypogonadal osteoporosis, corresponding to a grade of sex steroid deficiency that in general will not occur in many elderly men. Testosterone replacement therapy has been shown to increase bone mineral density in men, however data in osteoporotic ageing males are scarce, and evidence on fracture risk reduction is lacking. We conclude that testosterone replacement therapy should not be used as a sole bone-specific treatment in osteoporotic elderly men.


Assuntos
Fraturas Ósseas , Osteoporose , Humanos , Masculino , Feminino , Idoso , Densidade Óssea , Osteoporose/epidemiologia , Osteoporose/tratamento farmacológico , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Fraturas Ósseas/tratamento farmacológico , Hormônios Esteroides Gonadais , Envelhecimento , Testosterona , Esteroides/uso terapêutico
18.
J Cachexia Sarcopenia Muscle ; 13(4): 2242-2253, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35686338

RESUMO

BACKGROUND: Cytochrome P450 4F3 (CYP4F3) is an ω-hydroxylase that oxidizes leukotriene B4 (LTB4), prostaglandins, and fatty acid epoxides. LTB4 is synthesized by leukocytes and acts as a chemoattractant for neutrophils, making it an essential component of the innate immune system. Recently, involvement of the LTB4 pathway was reported in various immunological disorders such as asthma, arthritis, and inflammatory bowel disease. We report a 26-year-old female with a complex immune phenotype, mainly marked by exhaustion, muscle weakness, and inflammation-related conditions. The molecular cause is unknown, and symptoms have been aggravating over the years. METHODS: Whole exome sequencing was performed and validated; flow cytometry and enzyme-linked immunosorbent assay were used to describe patient's phenotype. Function and impact of the mutation were investigated using molecular analysis: co-immunoprecipitation, western blot, and enzyme-linked immunosorbent assay. Capillary electrophoresis with ultraviolet detection was used to detect LTB4 and its metabolite and in silico modelling provided structural information. RESULTS: We present the first report of a patient with a heterozygous de novo missense mutation c.C1123 > G;p.L375V in CYP4F3 that severely impairs its activity by 50% (P < 0.0001), leading to reduced metabolization of the pro-inflammatory LTB4. Systemic LTB4 levels (1034.0 ± 75.9 pg/mL) are significantly increased compared with healthy subjects (305.6 ± 57.0 pg/mL, P < 0.001), and immune phenotyping shows increased total CD19+ CD27- naive B cells (25%) and decreased total CD19+ CD27+ IgD- switched memory B cells (19%). The mutant CYP4F3 protein is stable and binding with its electron donors POR and Cytb5 is unaffected (P > 0.9 for both co-immunoprecipitation with POR and Cytb5). In silico modelling of CYP4F3 in complex with POR and Cytb5 suggests that the loss of catalytic activity of the mutant CYP4F3 is explained by a disruption of an α-helix that is crucial for the electron shuffling between the electron carriers and CYP4F3. Interestingly, zileuton still inhibits ex vivo LTB4 production in patient's whole blood to 2% of control (P < 0.0001), while montelukast and fluticasone do not (99% and 114% of control, respectively). CONCLUSIONS: A point mutation in the catalytic domain of CYP4F3 is associated with high leukotriene B4 plasma levels and features of a more naive adaptive immune response. Our data provide evidence for the pathogenicity of the CYP4F3 variant as a cause for the observed clinical features in the patient. Inhibitors of the LTB4 pathway such as zileuton show promising effects in blocking LTB4 production and might be used as a future treatment strategy.


Assuntos
Leucotrieno B4 , Mutação de Sentido Incorreto , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Família 4 do Citocromo P450/genética , Elétrons , Feminino , Humanos , Leucotrieno B4/metabolismo
19.
Endocrinology ; 163(7)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35640239

RESUMO

Failure of bone mass maintenance in spite of functional loading is an important contributor to osteoporosis and related fractures. While the link between sex steroids and the osteogenic response to loading is well established, the underlying mechanisms are unknown, hampering clinical relevance. Androgens inhibit mechanoresponsiveness in male mice, but the cell type mediating this effect remains unidentified. To evaluate the role of neuronal sex steroid receptor signaling in the male bone's adaptive capacity, we subjected adult male mice with an extrahypothalamic neuron-specific knockout of the androgen receptor (N-ARKO) or the estrogen receptor alpha (N-ERαKO) to in vivo mechanical stimulation of the tibia. Loading increased cortical thickness in the control animals mainly through periosteal expansion, as total cross-sectional tissue area and cortical bone area but not medullary area were higher in the loaded than the unloaded tibia. Trabecular bone volume fraction also increased upon loading in the control group, mostly due to trabecular thickening. N-ARKO and N-ERαKO males displayed a loading response at both the cortical and trabecular bone compartments that was not different from their control littermates. In conclusion, we show that the presence of androgen receptor or estrogen receptor alpha in extrahypothalamic neurons is dispensable for the osteogenic response to mechanical loading in male mice.


Assuntos
Receptor alfa de Estrogênio , Receptores Androgênicos , Animais , Estudos Transversais , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Tíbia
20.
Cancers (Basel) ; 14(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35454886

RESUMO

BACKGROUND: Previous studies have shown that different alcoholic beverage types impact prostate cancer (PCa) clinical outcomes differently. However, intake patterns of specific alcoholic beverages for PCa status are understudied. The study's objective is to evaluate intake patterns of total alcohol and the three types of beverage (beer, wine, and spirits) by the PCa risk and aggressiveness status. METHOD: This is a cross-sectional study using 10,029 men (4676 non-PCa men and 5353 PCa patients) with European ancestry from the PCa consortium. Associations between PCa status and alcohol intake patterns (infrequent, light/moderate, and heavy) were tested using multinomial logistic regressions. RESULTS: Intake frequency patterns of total alcohol were similar for non-PCa men and PCa patients after adjusting for demographic and other factors. However, PCa patients were more likely to drink wine (light/moderate, OR = 1.11, p = 0.018) and spirits (light/moderate, OR = 1.14, p = 0.003; and heavy, OR = 1.34, p = 0.04) than non-PCa men. Patients with aggressive PCa drank more beer than patients with non-aggressive PCa (heavy, OR = 1.48, p = 0.013). Interestingly, heavy wine intake was inversely associated with PCa aggressiveness (OR = 0.56, p = 0.009). CONCLUSIONS: The intake patterns of some alcoholic beverage types differed by PCa status. Our findings can provide valuable information for developing custom alcohol interventions for PCa patients.

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