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Sample records for duplicated androgen receptor

  1. The fate of the duplicated androgen receptor in fishes: a late neofunctionalization event?

    PubMed Central

    2008-01-01

    Background Based on the observation of an increased number of paralogous genes in teleost fishes compared with other vertebrates and on the conserved synteny between duplicated copies, it has been shown that a whole genome duplication (WGD) occurred during the evolution of Actinopterygian fish. Comparative phylogenetic dating of this duplication event suggests that it occurred early on, specifically in teleosts. It has been proposed that this event might have facilitated the evolutionary radiation and the phenotypic diversification of the teleost fish, notably by allowing the sub- or neo-functionalization of many duplicated genes. Results In this paper, we studied in a wide range of Actinopterygians the duplication and fate of the androgen receptor (AR, NR3C4), a nuclear receptor known to play a key role in sex-determination in vertebrates. The pattern of AR gene duplication is consistent with an early WGD event: it has been duplicated into two genes AR-A and AR-B after the split of the Acipenseriformes from the lineage leading to teleost fish but before the divergence of Osteoglossiformes. Genomic and syntenic analyses in addition to lack of PCR amplification show that one of the duplicated copies, AR-B, was lost in several basal Clupeocephala such as Cypriniformes (including the model species zebrafish), Siluriformes, Characiformes and Salmoniformes. Interestingly, we also found that, in basal teleost fish (Osteoglossiformes and Anguilliformes), the two copies remain very similar, whereas, specifically in Percomorphs, one of the copies, AR-B, has accumulated substitutions in both the ligand binding domain (LBD) and the DNA binding domain (DBD). Conclusion The comparison of the mutations present in these divergent AR-B with those known in human to be implicated in complete, partial or mild androgen insensitivity syndrome suggests that the existence of two distinct AR duplicates may be correlated to specific functional differences that may be connected to the well

  2. Mechanism of androgen receptor action.

    PubMed

    Li, Jin; Al-Azzawi, Farook

    2009-06-20

    Recent research provides a much more detailed understanding of the role of the androgen receptor in normal human development and physiology, its structure, and its functioning. This review discusses genomic and non-genomic actions of the androgen receptor, as well as their co-regulators. We also explore several clinically relevant aspects of the molecular biology of the androgen receptor and its co-regulators. PMID:19372015

  3. Androgen receptor genomic regulation

    PubMed Central

    Jin, Hong-Jian; Kim, Jung

    2013-01-01

    The transcriptional activity of the androgen receptor (AR) is not only critical for the normal development and function of the prostate but also pivotal to the onset and progression of prostate cancer (PCa). The studies of AR transcriptional regulation were previously limited to a handful of AR-target genes. Owing to the development of various high-throughput genomic technologies, significant advances have been made in recent years. Here we discuss the discoveries of genome-wide androgen-regulated genes in PCa cell lines, animal models and tissues using expression microarray and sequencing, the mapping of genomic landscapes of AR using Combining Chromatin Immunoprecipitation (ChIP)-on-chip and ChIP-seq assays, the interplay of transcriptional cofactors in defining AR binding profiles, and the genomic regulation and AR reprogramming in advanced PCa. PMID:25237629

  4. Alternatively Spliced Androgen Receptor Variants

    PubMed Central

    Dehm, Scott M.; Tindall, Donald J.

    2011-01-01

    Alternative splicing is an important mechanism for increasing functional diversity from a limited set of genes. De-regulation of this process is common in diverse pathologic conditions. The androgen receptor (AR) is a steroid receptor transcription factor with functions critical for normal male development as well as the growth and survival of normal and cancerous prostate tissue. Studies of AR function in androgen insensitivity syndrome (AIS) and prostate cancer (PCa) have demonstrated loss-of-function AR alterations in AIS, and gain-of-function AR alterations in PCa. Over the past two decades, AR gene alterations have been identified in various individuals with AIS, which disrupt normal AR splicing patterns and yield dysfunctional AR protein variants. More recently, altered AR splicing patterns have been identified as a mechanism of PCa progression and resistance to androgen-depletion therapy. Several studies have described the synthesis of alternatively spliced transcripts encoding truncated AR isoforms that lack the ligand-binding domain, which is the ultimate target of androgen depletion. Many of these truncated AR isoforms function as constitutively active, ligand-independent transcription factors that can support androgen-independent expression of AR target genes, as well as the androgen-independent growth of PCa cells. In this review, we will summarize the various alternatively spliced AR variants that have been discovered, with a focus on their role and origin in the pathologic conditions of AIS and PCa. PMID:21778211

  5. Androgen receptor polymorphism (CAG repeats) and androgenicity.

    PubMed

    Canale, D; Caglieresi, C; Moschini, C; Liberati, C D; Macchia, E; Pinchera, A; Martino, E

    2005-09-01

    Objective Polymorphism of the androgen receptor (AR) has been related to various pathophysiological conditions, such as osteoporosis and infertility. The objectives of this study were to evaluate the frequency of distribution in a normal Italian population and to assess CAG repeats (CAGr) in other conditions, such as hypoandrogenism, potentially influenced by AR polymorphism. Patients and measurements CAGr polymorphism was determined in a group of 91 healthy normoandrogenized subjects, 29 hypoandrogenized patients (hypoplasia of prostate and seminal vesicles, reduced beard or body hair, etc.) and 29 infertile patients by direct sequencing. Results The mean (+/- SD) number of CAG repeats [(CAGr)n] was 21.5 (+/- 1.7) in the control group, 21.4 (+/- 2.0) in the infertile patients and 24.0 (+/- 2.9) in the hypoandrogenic males. The difference was statistically significant between this last group and the other two (P < 0.0001), while there was no difference between normal controls and infertile patients. The frequency distribution showed a shift towards higher CAG length in hypoandrogenized patients compared to controls and infertile patients. If we used a cut-off point of 24.9 (2 SD above the mean), the percentage of patients with 25 or more CAGr repeats was 38% among hypoandrogenized patients, 7% among infertile patients and 5% among the control group. In hypoandrogenized subjects (CAGr)n correlated slightly with testis and prostate volume. The number of CAG repeats was not associated with any of the hormonal parameters, including testosterone, evaluated in the three groups. Conclusions Our normal population, representing subjects from Central Italy, is superimposable on other European populations with regard to (CAGr)n distribution. Hypoandrogenic males have a shift in the frequency distribution towards longer (CAGr)n. Infertile patients are not statistically different from the control group. These findings suggest that, given the same amount of circulating

  6. Androgen receptors in prostate cancer.

    PubMed

    Culig, Z; Klocker, H; Bartsch, G; Hobisch, A

    2002-09-01

    The androgen receptor (AR), a transcription factor that mediates the action of androgens in target tissues, is expressed in nearly all prostate cancers. Carcinoma of the prostate is the most frequently diagnosed neoplasm in men in industrialized countries. Palliative treatment for non-organ-confined prostate cancer aims to down-regulate the concentration of circulating androgen or to block the transcription activation function of the AR. AR function during endocrine therapy was studied in tumor cells LNCaP subjected to long-term steroid depletion; newly generated sublines could be stimulated by lower concentrations of androgen than parental cells and showed up-regulation of AR expression and activity as well as resistance to apoptosis. Androgenic hormones regulate the expression of key cell cycle regulators, cyclin-dependent kinase 2 and 4, and that of the cell cycle inhibitor p27. Inhibition of AR expression could be achieved by potential chemopreventive agents flufenamic acid, resveratrol, quercetin, polyunsaturated fatty acids and interleukin-1beta, and by the application of AR antisense oligonucleotides. In the clinical situation, AR gene amplification and point mutations were reported in patients with metastatic disease. These mutations generate receptors which could be activated by other steroid hormones and non-steroidal antiandrogens. In the absence of androgen, the AR could be activated by various growth-promoting (growth factors, epidermal growth factor receptor-related oncogene HER-2/neu) and pleiotropic (protein kinase A activators, interleukin-6) compounds as well as by inducers of differentiation (phenylbutyrate). AR function is modulated by a number of coactivators and corepressors. The three coactivators, TIF-2, SRC-1 and RAC3, are up-regulated in relapsed prostate cancer. New experimental therapies for prostate cancer are aimed to down-regulate AR expression and to overcome difficulties which occur because of the acquisition of agonistic properties

  7. The androgen receptor in health and disease.

    PubMed

    Matsumoto, Takahiro; Sakari, Matomo; Okada, Maiko; Yokoyama, Atsushi; Takahashi, Sayuri; Kouzmenko, Alexander; Kato, Shigeaki

    2013-01-01

    Androgens play pivotal roles in the regulation of male development and physiological processes, particularly in the male reproductive system. Most biological effects of androgens are mediated by the action of nuclear androgen receptor (AR). AR acts as a master regulator of downstream androgen-dependent signaling pathway networks. This ligand-dependent transcriptional factor modulates gene expression through the recruitment of various coregulator complexes, the induction of chromatin reorganization, and epigenetic histone modifications at target genomic loci. Dysregulation of androgen/AR signaling perturbs normal reproductive development and accounts for a wide range of pathological conditions such as androgen-insensitive syndrome, prostate cancer, and spinal bulbar muscular atrophy. In this review we summarize recent advances in understanding of the epigenetic mechanisms of AR action as well as newly recognized aspects of AR-mediated androgen signaling in both men and women. In addition, we offer a perspective on the use of animal genetic model systems aimed at eventually developing novel therapeutic AR ligands. PMID:23157556

  8. Interactions of methoxyacetic acid with androgen receptor

    SciTech Connect

    Bagchi, Gargi; Hurst, Christopher H.; Waxman, David J.

    2009-07-15

    Endocrine disruptive compounds (EDC) alter hormone-stimulated, nuclear receptor-dependent physiological and developmental processes by a variety of mechanisms. One recently identified mode of endocrine disruption is through hormone sensitization, where the EDC modulates intracellular signaling pathways that control nuclear receptor function, thereby regulating receptor transcriptional activity indirectly. Methoxyacetic acid (MAA), the primary, active metabolite of the industrial solvent ethylene glycol monomethyl ether and a testicular toxicant, belongs to this EDC class. Modulation of nuclear receptor activity by MAA could contribute to the testicular toxicity associated with MAA exposure. In the present study, we evaluated the impact of MAA on the transcriptional activity of several nuclear receptors including the androgen receptor (AR), which plays a pivotal role in the development and maturation of spermatocytes. AR transcriptional activity is shown to be increased by MAA through a tyrosine kinase signaling pathway that involves PI3-kinase. In a combinatorial setting with AR antagonists, MAA potentiated the AR response without significantly altering the EC{sub 50} for androgen responsiveness, partially alleviating the antagonistic effect of the anti-androgens. Finally, MAA treatment of TM3 mouse testicular Leydig cells markedly increased the expression of Cyp17a1 and Shbg while suppressing Igfbp3 expression by {approx} 90%. Deregulation of these genes may alter androgen synthesis and action in a manner that contributes to MAA-induced testicular toxicity.

  9. Adolescents and Androgens, Receptors and Rewards

    PubMed Central

    Sato, Satoru M.; Schulz, Kalynn M.; Sisk, Cheryl L.; Wood, Ruth I.

    2008-01-01

    Adolescence is associated with increases in pleasure-seeking behaviors, which, in turn, are shaped by the pubertal activation of the hypothalamo-pituitary-gonadal axis. In animal models of naturally rewarding behaviors, such as sex, testicular androgens contribute to the development and expression of the behavior in males. To effect behavioral maturation, the brain undergoes significant remodeling during adolescence, and many of the changes are likewise sensitive to androgens, presumably acting through androgen receptors (AR). Given the delicate interaction of gonadal hormones and brain development, it is no surprise that disruption of hormone levels during this sensitive period significantly alters adolescent and adult behaviors. In male hamsters, exposure to testosterone during adolescence is required for normal expression of adult sexual behavior. Males deprived of androgens during puberty display sustained deficits in mating. Conversely, androgens alone are not sufficient to induce mating in prepubertal males, even though brain AR are present before puberty. In this context, wide-spread use of anabolic-androgenic steroids (AAS) during adolescence is a significant concern. AAS abuse has the potential to alter both the timing and the levels of androgens in adolescent males. In hamsters, adolescent AAS exposure increases aggression, and causes lasting changes in neurotransmitter systems. In addition, AAS are themselves reinforcing, as demonstrated by self-administration of testosterone and other AAS. However, recent evidence suggests that the reinforcing effects of androgens may not require classical AR. Therefore, further examination of interactions between androgens and rewarding behaviors in the adolescent brain is required for a better understanding of AAS abuse. PMID:18343381

  10. Androgen receptor in human endothelial cells

    PubMed Central

    Torres-Estay, Verónica; Carreño, Daniela V; San Francisco, Ignacio F; Sotomayor, Paula; Godoy, Alejandro S; Smith, Gary J

    2015-01-01

    Androgen receptor (AR) is a ligand-inducible transcription factor, and a member of the steroid-thyroid-retinoid receptor superfamily, that mediates the biological effects of androgens in a wide range of physiological and pathological processes. AR expression was identified in vascular cells nearly 20 years ago, and recent research has shown that AR mediates a variety of actions of androgens in endothelial and vascular smooth muscle cells. In this mini-review, we review evidence indicating the importance of AR in human endothelial cell (HUVEC) homeostatic and pathogenic processes. Although a role for AR in the modulation of HUVEC biology is evident, the molecular mechanisms by which AR regulates HUVEC homeostasis and disease processes are not fully understood. Understanding these mechanisms could provide critical insights into the processes of pathogenesis of diseases ranging from cardiovascular disease to cancer that are major causes of human morbidity and mortality. PMID:25563353

  11. Androgen receptor gene polymorphism in zebra species

    PubMed Central

    Ito, Hideyuki; Langenhorst, Tanya; Ogden, Rob; Inoue-Murayama, Miho

    2015-01-01

    Androgen receptor genes (AR) have been found to have associations with reproductive development, behavioral traits, and disorders in humans. However, the influence of similar genetic effects on the behavior of other animals is scarce. We examined the loci AR glutamine repeat (ARQ) in 44 Grevy's zebras, 23 plains zebras, and three mountain zebras, and compared them with those of domesticated horses. We observed polymorphism among zebra species and between zebra and horse. As androgens such as testosterone influence aggressiveness, AR polymorphism among equid species may be associated with differences in levels of aggression and tameness. Our findings indicate that it would be useful to conduct further studies focusing on the potential association between AR and personality traits, and to understand domestication of equid species. PMID:26236645

  12. The Role of Androgen and Androgen Receptor in the Skin-Related Disorders

    PubMed Central

    Lai, Jiann-Jyh; Chang, Philip; Lai, Kuo-Pao; Chen, Lumin; Chang, Chawnshang

    2013-01-01

    Androgen and androgen receptor (AR) may play important roles in several skin related diseases, such as androgenetic alopecia and acne vulgaris. Current treatments for these androgen/AR-involved diseases, which target the synthesis of androgens or prevent its binding to AR, can cause significant adverse side effects. Based on the recent studies using AR knockout mice, it has been suggested that AR and androgens play distinct roles in the skin pathogenesis, and AR seems to be a better target than androgens for the treatment of these skin diseases. Here we review recent studies of androgen/AR roles in several skin-related disorders, including acne vulgaris, androgenetic alopecia, and hirsutism, as well as cutaneous wound healing. PMID:22829074

  13. Transcriptional up-regulation of the human androgen receptor by androgen in bone cells.

    PubMed

    Wiren, K M; Zhang, X; Chang, C; Keenan, E; Orwoll, E S

    1997-06-01

    Androgen regulation of androgen receptor (AR) expression has been observed in a variety of tissues, generally as inhibition, and is thought to attenuate cellular responses to androgen. AR is expressed in osteoblasts, the bone-forming cell, suggesting direct actions of androgens on bone. Here we characterized the effect of androgen exposure on AR gene expression in human osteoblastic SaOS-2 and U-2 OS cells. Treatment of osteoblastic cells with the nonaromatizable androgen 5alpha-dihydrotestosterone increased AR steady state messenger RNA levels in a time- and dose-dependent fashion. Reporter assays with 2.3 kilobases of the proximal 5'-flanking region of the human AR promoter linked to the chloramphenicol acetyltransferase gene in transfected cultures showed that up-regulation of AR promoter activity by androgen was time and dose dependent. Treatment with other steroid hormones, including progesterone, 17beta-estradiol, and dexamethasone, was without effect. The antiandrogen hydroxyflutamide completely antagonized androgen up-regulation. Thus, in contrast to many other androgen target tissues, androgen exposure increases steady state AR messenger RNA levels in osteoblasts. This regulation occurs at least partially at the level of transcription, is mediated by the 5'-promoter region of the AR gene, and is dependent on functional AR. These results suggest that physiological concentrations of androgens have significant effects on AR expression in skeletal tissue. PMID:9165014

  14. Genetic basis of endocrine disease 4: The spectrum of mutations in the androgen receptor gene that causes androgen resistance

    SciTech Connect

    McPhaul, M.J.; Marcelli, M.; Zoppi, S.; Griffin, J.E.; Wilson, J.D. )

    1993-01-01

    Mutations in the androgen receptor gene cause phenotypic abnormalities of male sexual development that range from a female phenotype (complete testicular feminization) to that of undervirilized or infertile men. Using the tools of molecular biology, the authors have analyzed androgen receptor gene mutations in 31 unrelated subjects with androgen resistance syndromes. Most of the defects are due to nucleotide changes that cause premature termination codons or single amino acid substitutions within the open reading frame encoding the androgen receptor, and the majority of these substitutions are localized in three regions of the androgen receptor: the DNA-binding domain and two segments of the androgen-binding domain. Less frequently, partial or complete gene deletions have been identified. Functional studies and immunoblot assays of the androgen receptors in patients with androgen resistance indicate that in most cases the phenotypic abnormalities are the result of impairment of receptor function or decreases in receptor abundance or both. 34 refs., 2 figs.

  15. RAINBOW TROUT ANDROGEN RECEPTOR ALPHA AND THE HUMAN ANDROGEN RECEPTOR: COMPARISONS IN THE COS WHOLE CELL BINDING ASSAY

    EPA Science Inventory

    Rainbow Trout Androgen Receptor Alpha And Human Androgen Receptor: Comparisons in the COS Whole Cell Binding Assay
    Mary C. Cardon, L. Earl Gray, Jr. and Vickie S. Wilson
    U.S. Environmental Protection Agency, ORD, NHEERL, Reproductive Toxicology Division, Research Triangle...

  16. RAINBOW TROUT ANDROGEN RECEPTOR ALPHA AND THE HUMAN ANDROGEN RECEPTOR: COMPARISONS IN THE COS WHOLE CELL BINDING ASSAY

    EPA Science Inventory

    RAINBOW TROUT ANDROGEN RECEPTOR ALPHA AND HUMAN ANDROGEN RECEPTOR: COMPARISONS IN THE COS WHOLE CELL BINDING ASSAY.
    MC Cardon, PC Hartig,LE Gray, Jr. and VS Wilson.
    U.S. EPA, ORD, NHEERL, RTD, Research Triangle Park, NC, USA.
    Typically, in vitro hazard assessments for ...

  17. Molecular pathways: targeting resistance in the androgen receptor for therapeutic benefit.

    PubMed

    Mostaghel, Elahe A; Plymate, Stephen R; Montgomery, Bruce

    2014-02-15

    Androgen receptor signaling is critical in the development and progression of prostate cancer, leading to intensive efforts to elucidate all potential points of inflection for therapeutic intervention. These efforts have revealed new mechanisms of resistance and raise the possibility that known mechanisms may become even more relevant in the context of effective androgen receptor suppression. These mechanisms include tumoral appropriation of alternative androgen sources, alterations in androgen receptor expression, androgen receptor mutations, truncated androgen receptor variants, alterations and cross-talk in recruitment of cofactors to androgen receptor binding sites in the genome, and androgen receptor-driven oncogenic gene fusions. New agents such as enzalutamide, EPI-001, androgen receptor-specific peptidomimetics, novel HSP90 inhibitors, and PARP inhibitors, as well as new approaches to cotargeting the androgen receptor pathway, point to the potential for more complete and durable control of androgen receptor-mediated growth. PMID:24305618

  18. Disruption of Androgen Receptor Signaling in Males by Environmental Chemicals

    PubMed Central

    Luccio-Camelo, Doug C.; Prins, Gail S

    2011-01-01

    Androgen-disruptors are environmental chemicals in that interfere with the biosynthesis, metabolism or action of endogenous androgens resulting in a deflection from normal male developmental programming and reproductive tract growth and function. Since male sexual differentiation is entirely androgen-dependent, it is highly susceptible to androgen-disruptors. Animal models and epidemiological evidence link exposure to androgen disrupting chemicals with reduced sperm counts, increased infertility, testicular dysgenesis syndrome, and testicular and prostate cancers. Further, there appears to be increased sensitivity to these agents during critical developmental windows when male differentiation is at its peak. A variety of in vitro and in silico approaches have been used to identify broad classes of androgen disrupting molecules that include organochlorinated pesticides, industrial chemicals, and plasticizers with capacity to ligand the androgen receptor. The vast majority of these synthetic molecules act as anti-androgens. This review will highlight the evidence for androgen disrupting chemicals that act through interference with the androgen receptor, discussing specific compounds for which there is documented in vivo evidence for male reproductive tract perturbations. PMID:21515368

  19. New insights into the androgen biotransformation in prostate cancer: A regulatory network among androgen, androgen receptors and UGTs.

    PubMed

    Qin, Xuan; Liu, Mingyao; Wang, Xin

    2016-04-01

    Androgen, as one kind of steroid hormones, is pivotal in the hormone-sensitive cancer, such as prostate cancer (PCa). The synthesis, elimination, and bioavailability of androgen in prostate cells have been proved to be a main cause of the carcinogenesis, maintenance and deterioration of PCa. This review illustrates the outlines of androgen biotransformation, and further discusses the different enzymes, especially UDP-glucuronyltransferases (UGTs) embedded in both benign and malignant prostate cells, which catalyze the reactions. Although many inhibitors of the enzymes responsible for the synthesis of androgens have been developed into drugs to fight against PCa, the elimination procedures metabolized by the UGTs are less emphasized. Thus the regulatory network among androgen, androgen receptors (AR) and UGTs is carefully reviewed in this article, indicating the determinant effects of UGTs on prostatic androgens and the regulation of AR. Finally, the hypothesis is also put forward that the regulators of UGTs may be developed to accelerate the androgen elimination and benefit PCa therapy. PMID:26926093

  20. Expression of a hyperactive androgen receptor leads to androgen-independent growth of prostate cancer cells.

    PubMed

    Hsieh, Chen-Lin; Cai, Changmeng; Giwa, Ahmed; Bivins, Aaronica; Chen, Shao-Yong; Sabry, Dina; Govardhan, Kumara; Shemshedini, Lirim

    2008-07-01

    Cellular changes that affect the androgen receptor (AR) can cause prostate cancer to transition from androgen dependent to androgen independent, which is usually lethal. One common change in prostate tumors is overexpression of the AR, which has been shown to lead to androgen-independent growth of prostate cancer cells. This led us to hypothesize that expression of a hyperactive AR would be sufficient for androgen-independent growth of prostate cancer cells. To test this hypothesis, stable lune cancer prostate (LNCaP) cell lines were generated, which express a virion phosphoprotein (VP)16-AR hybrid protein that contains full-length AR fused to the strong viral transcriptional activation domain VP16. This fusion protein elicited as much as a 20-fold stronger transcriptional activity than the natural AR. Stable expression of VP16-AR in LNCaP cells yielded androgen-independent cell proliferation, while under the same growth conditions the parental LNCaP cells exhibited only androgen-dependent growth. These results show that expression of a hyperactive AR is sufficient for androgen-independent growth of prostate cancer cells. To study the molecular basis of this enhanced growth, we measured the expression of soluble guanylyl cyclase-alpha1 (sGCalpha1), a subunit of the sGC, an androgen-regulated gene that has been shown to be involved in prostate cancer cell growth. Interestingly, the expression of sGCalpha1 is androgen independent in VP16-AR-expressing cells, in contrast to its androgen-induced expression in control LNCaP cells. RNA(I)-dependent inhibition of sGCalpha1 expression resulted in significantly reduced proliferation of VP16-AR cells, implicating an important role for sGCalpha1 in the androgen-independent growth of these cells. PMID:18469090

  1. Racial differences in the androgen/androgen receptor pathway in prostate cancer.

    PubMed Central

    Pettaway, C. A.

    1999-01-01

    Pathologic and epidemiologic data suggest that while little racial variation exists in prostate cancer prevalence ("autopsy cancer"), striking racial variation exists for the clinically diagnosed form of the disease. A review of the available literature was performed to define whether racial differences in serum androgen levels or qualitative or quantitative differences in the androgen receptor were correlated with prostate cancer incidence or severity. Black men were found to be exposed to higher circulating testosterone levels from birth to about age 35 years. Such differences were not consistently noted among older men. Significant differences also were found for dihydrotestosterone metabolites among black, white, and Asian men. Unique racial genetic polymorphisms were noted for the gene for 5 alpha-reductase type 2 among black and Asian men. Novel androgen receptor mutations recently have been described among Japanese, but not white, men with latent prostate cancer. Finally, androgen receptor gene polymorphisms leading to shorter or longer glutamine and glycine residues in the receptor protein are correlated with racial variation in the incidence and severity of prostate cancer. This same polymorphism also could explain racial variation in serum prostate-specific antigen levels. Collectively, these data strongly suggest racial differences within the androgen/androgen receptor pathway not only exist but could be one cause of clinically observed differences in the biology of prostate cancer among racial groups. Images Figure 1 PMID:10628124

  2. The effect of anabolic-androgenic steroids on aromatase activity and androgen receptor binding in the rat preoptic area.

    PubMed

    Roselli, C E

    1998-05-11

    The level of aromatase in the preoptic area of rats is transcriptionally regulated through a specific androgen-receptor mediated mechanism and can be used as a measure of central androgenic effect. Therefore, several commonly abused anabolic-androgenic steroids (AAS) were tested for their ability to induce aromatase activity in the preoptic area of castrated rats. In addition, we determined the relative binding affinities of these compounds for the androgen receptor, as well as their ability to bind androgen receptor in vivo following subcutaneous injections. All of the AAS compounds tested significantly stimulated POA aromatase activity above castrate levels. The compounds that produced the greatest stimulation of aromatase activity were those that bound most avidly to the androgen receptor in vitro (i.e., testosterone, dihydrotestosterone and nandrolone). In contrast, the 17alpha-alkylated compounds that were tested (stanozolol, danazol, methandrostenolone) modestly stimulated aromatase and were weak competitors for the androgen receptor. The subcutaneous injection of AAS compounds increased the concentrations of occupied nuclear androgen receptors in the brain, but the magnitude of effect was not related to their potency for inducing aromatase or their relative binding affinity for the androgen receptor suggesting that androgen receptor occupancy in POA is not correlated with the action of androgen on aromatase. The present results help explain the behavioral effects of AAS compounds in rats. PMID:9593936

  3. Evolutionary Fate of the Androgen Receptor-Signaling Pathway in Ray-Finned Fishes with a Special Focus on Cichlids.

    PubMed

    Lorin, Thibault; Salzburger, Walter; Böhne, Astrid

    2015-11-01

    The emergence of the steroid system is coupled to the evolution of multicellular animals. In vertebrates in particular, the steroid receptor repertoire has been shaped by genome duplications characteristic to this lineage. Here, we investigate for the first time the composition of the androgen receptor-signaling pathway in ray-finned fish genomes by focusing in particular on duplicates that emerged from the teleost-specific whole-genome duplication. We trace lineage- and species-specific duplications and gene losses for the genomic and nongenomic pathway of androgen signaling and subsequently investigate the sequence evolution of these genes. In one particular fish lineage, the cichlids, we find evidence for differing selection pressures acting on teleost-specific whole-genome duplication paralogs at a derived evolutionary stage. We then look into the expression of these duplicated genes in four cichlid species from Lake Tanganyika indicating, once more, rapid changes in expression patterns in closely related fish species. We focus on a particular case, the cichlid specific duplication of the rac1 GTPase, which shows possible signs of a neofunctionalization event. PMID:26333839

  4. Binding kinetics and physical properties of androgen receptor in androgen-dependent Shionogi mammary carcinoma 115.

    PubMed

    Nohno, T

    1981-02-01

    The characteristics of the androgen receptor in the cytoplasmic fraction of Shionogi carcinoma 115 were studied in vitro by means of charcoal adsorption assay, sucrose density gradient centrifugation, and polyacrylamide gel electrophoresis. The equilibrium dissociation constant for [3H]dihydrotestosterone (Kd = (2-5) X 10(-11) M) was estimated from independently determined rates of association and dissociation, and was lower by one order of magnitude than the value obtained by saturation analysis (Kd = (2-8) X 10(-10) M). Evaluation of the effect of temperature on receptor binding of androgen allowed the estimation of several thermodynamic parameters, including activation energies of association (4 kcal/mol) and dissociation (14 kcal/mol), the apparent free energy (-13 kcal/mol), enthalpy (-9 kcal/mol), and entropy (+14 cal/mol per K). The receptor was greatly stabilized when bound with androgen. The results indicate how the lability of the unbound receptor and slow rate of dihydrotestosterone-receptor interaction can influence the estimation of dissociation constants by usual saturation analysis. The sedimentation coefficient of androgen receptor in freshly prepared cytosol was 6S, and became 7S after storage for 2 months at -80 degrees C. The 7S conversion of the receptor was reversed by treatment with heparin. In all cases, a single 5S peak was obtained in the presence of 0.5 M KCl. On electrophoresis in heparin-containing polyacrylamide gel, protein-bound radioactive androgen migrated as a single peak (Rf = 0.5 in 5% gel). Differences in reported values for the sedimentation coefficient of androgen receptor in cytosol of Shionogi carcinoma 115 appear to be derived from aggregation of the receptor protein during the assay procedure. PMID:7240130

  5. [Role of androgen in the elderly. Current status of development of selective androgen receptor modulator].

    PubMed

    Yanase, Toshihiko

    2013-08-01

    The research to develop a drug, so called selective androgen receptor modulator (SARM) , which shows beneficial androgenic action on bone and muscle, but hardly possesses the stimulatory action on prostate has been making a progress. However, no drug is available in the market at present. Most of such drugs are developed, aiming at the application to age-related muscle reduction (sarcopenia) and osteoporosis. We are now trying to develop a SARM which may have beneficial effect on metabolic syndrome. PMID:23892218

  6. Artificial masculinization in tilapia involves androgen receptor activation.

    PubMed

    Golan, Matan; Levavi-Sivan, Berta

    2014-10-01

    Estrogens have a pivotal role in natural female sexual differentiation of tilapia while lack of steroids results in testicular development. Despite the fact that androgens do not participate in natural sex differentiation, synthetic androgens, mainly 17-α-methyltestosterone (MT) are effective in the production of all-male fish in aquaculture. The sex inversion potency of synthetic androgens may arise from their androgenic activity or else as inhibitors of aromatase activity. The current study is an attempt to differentiate between the two alleged activities in order to evaluate their contribution to the sex inversion process and aid the search for novel sex inversion agents. In the present study, MT inhibited aromatase activity, when applied in vitro as did the non-aromatizable androgen dihydrotestosterone (DHT). In comparison, exposure to fadrozole, a specific aromatase inhibitor, was considerably more effective. Androgenic activity of MT was evaluated by exposure of Sciaenochromis fryeri fry to the substance and testing for the appearance of blue color. Flutamide, an androgen antagonist, administered concomitantly with MT, reduced the appearance of the blue color and the sex inversion potency of MT in a dose-dependent manner. In tilapia, administration of MT, fadrozole or DHT resulted in efficient sex inversion while flutamide reduced the sex inversion potency of all three compounds. In the case of MT and DHT the decrease in sex inversion efficiency caused by flutamide is most likely due to the direct blocking of the androgen binding to its cognate receptor. The negative effect of flutamide on the efficiency of the fadrozole treatment may indicate that the masculinizing activity of fadrozole may be attributed to excess, un-aromatized, androgens accumulated in the differentiating gonad. The present study shows that when androgen receptors are blocked, there is a reduction in the efficiency of sex inversion treatments. Our results suggest that in contrast to

  7. Glucocorticoid Receptor Confers Resistance to Anti-Androgens by Bypassing Androgen Receptor Blockade

    PubMed Central

    Arora, Vivek K.; Schenkein, Emily; Murali, Rajmohan; Subudhi, Sumit K.; Wongvipat, John; Balbas, Minna D.; Shah, Neel; Cai, Ling; Efstathiou, Eleni; Logothetis, Chris; Zheng, Deyou; Sawyers, Charles L.

    2014-01-01

    Summary The treatment of advanced prostate cancer has been transformed by novel antiandrogen therapies such as enzalutamide. Here we identify induction of glucocorticoid receptor (GR) expression as a common feature of drug resistant tumors in a credentialed preclinical model, a finding also confirmed in patient samples. GR substituted for the androgen receptor (AR) to activate a similar but distinguishable set of target genes and was necessary for maintenance of the resistant phenotype. The GR agonist dexamethasone was sufficient to confer enzalutamide resistance whereas a GR antagonist restored sensitivity. Acute AR inhibition resulted in GR upregulation in a subset of prostate cancer cells due to relief of AR-mediated feedback repression of GR expression. These findings establish a novel mechanism of escape from AR blockade through expansion of cells primed to drive AR target genes via an alternative nuclear receptor upon drug exposure. PMID:24315100

  8. Substitution of synthetic chimpanzee androgen receptor for human androgen receptor in competitive binding and transcriptional activation assays for EDC screening

    EPA Science Inventory

    The potential effect of receptor-mediated endocrine modulators across species is of increasing concern. In attempts to address these concerns we are developing androgen and estrogen receptor binding assays using recombinant hormone receptors from a number of species across differ...

  9. Androgen receptor-related diseases: what do we know?

    PubMed

    Shukla, G C; Plaga, A R; Shankar, E; Gupta, S

    2016-05-01

    The androgen receptor (AR) and the androgen-AR signaling pathway play a significant role in male sexual differentiation and the development and function of male reproductive and non-reproductive organs. Because of AR's widely varied and important roles, its abnormalities have been identified in various diseases such as androgen insensitivity syndrome, spinal bulbar muscular atrophy, benign prostatic hyperplasia, and prostate cancer. This review provides an overview of the function of androgens and androgen-AR mediated diseases. In addition, the diseases delineated above are discussed with respect to their association with mutations and other post-transcriptional modifications in the AR. Finally, we present an introduction to the potential therapeutic application of most recent pharmaceuticals including miRNAs in prostate cancer that specifically target the transactivation function of the AR at post-transcriptional stages. PMID:26991422

  10. Constitutive Activity of the Androgen Receptor

    PubMed Central

    Chan, Siu Chiu; Dehm, Scott M.

    2014-01-01

    Prostate cancer (PCa) is the most frequently diagnosed cancer in the United States. The androgen receptor (AR) signaling axis is central to all stages of PCa pathophysiology and serves as the main target for endocrine-based therapy. The most advanced stage of the disease, castration resistant prostate cancer (CRPC), is presently incurable and accounts for most PCa mortality. In this review, we highlight the mechanisms by which the AR signaling axis can bypass endocrine-targeted therapies and drive progression of CRPC. These mechanisms include alterations in growth factor, cytokine, and inflammatory signaling pathways, altered expression or activity of transcriptional co-regulators, AR point mutations, and AR gene amplification leading to AR protein overexpression. Additionally, we will discuss the mechanisms underlying the synthesis of constitutively active AR splice variants (AR-Vs) lacking the COOH-terminal ligand binding domain, as well as the role and regulation of AR-Vs in supporting therapeutic resistance in CRPC. Finally, we summarize the ongoing development of inhibitors targeting discrete AR functional domains as well as the status of new biomarkers for monitoring the AR signaling axis in patients. PMID:24931201

  11. Aberrant splicing of androgenic receptor mRNA results in synthesis of a nonfunctional receptor protein in a patient with androgen insensitivity

    SciTech Connect

    Ris-Stalpers, C.; Kuiper, G.G.J.M.; Faber, P.W.; van Rooij, H.C.J.; Degenhart, H.J.; Trapman, J.; Brinkmann, A.O. ); Schweikert, H.U. ); Zegers, N.D. ); Hodgins, M.B. )

    1990-10-01

    Androgen insensitivity is a disorder in which the correct androgen response in an androgen target cell is impaired. The clinical symtpoms of this X chromosome-linked syndrome are presumed to be caused by mutations in the androgen receptor gene. The authors report a G {r arrow} T mutation in the splice donor site of intron 4 of the androgen receptor gene of a 46, XY subject lacking detectable androgen binding to the receptor and with the complete form of androgen insensitivity. This point mutation completely abolishes normal RNA splicing at the exon 4/intron 4 boundary and results in the activation of a cryptic splice donor site in exon 4, which leads to the deletion of 123 nucleotides from the mRNA. Translation of the mutant mRNA results in an androgen receptor protein {approx}5 kDa smaller than the wild type. This mutated androgen receptor protein was unable to bind androgens and unable to activate transcription of an androgen-regulated reporter gene construct. This mutation in the human androgen receptor gene demonstrates the importance of an intact steroid-binding domain for proper androgen receptor functioning in vivo.

  12. [The mechanisms of prostate cancer progression through androgen receptor].

    PubMed

    Goto, Yusuke; Sakamoto, Shinichi; Ichikawa, Tomohiko

    2016-01-01

    Androgen receptor(AR) has a critical role in prostate cancer(PCa) progression and targeting AR axis signaling by androgen deprivation therapy is a standard treatment for advanced PCa. Recently, the role of AR even in castration-resistant PCa(CRPC) is well recognized and emerging evidence suggests survival advantages of treatment by targeting AR in CRPC. This review outlines AR functions that contribute to PCa progression, AR structural alterations and AR activation via intracrine, co-factors, and kinase pathways in CRPC. Finally, we describe about recently reported bipolar androgen therapy as a novel treatment for CRPC targeting AR. PMID:26793880

  13. Androgen receptor: structure, role in prostate cancer and drug discovery

    PubMed Central

    Tan, MH Eileen; Li, Jun; Xu, H Eric; Melcher, Karsten; Yong, Eu-leong

    2015-01-01

    Androgens and androgen receptors (AR) play a pivotal role in expression of the male phenotype. Several diseases, such as androgen insensitivity syndrome (AIS) and prostate cancer, are associated with alterations in AR functions. Indeed, androgen blockade by drugs that prevent the production of androgens and/or block the action of the AR inhibits prostate cancer growth. However, resistance to these drugs often occurs after 2–3 years as the patients develop castration-resistant prostate cancer (CRPC). In CRPC, a functional AR remains a key regulator. Early studies focused on the functional domains of the AR and its crucial role in the pathology. The elucidation of the structures of the AR DNA binding domain (DBD) and ligand binding domain (LBD) provides a new framework for understanding the functions of this receptor and leads to the development of rational drug design for the treatment of prostate cancer. An overview of androgen receptor structure and activity, its actions in prostate cancer, and how structural information and high-throughput screening have been or can be used for drug discovery are provided herein. PMID:24909511

  14. Effects of androgen on immunohistochemical localization of androgen receptor and Connexin 43 in mouse ovary.

    PubMed

    Yang, Mei; Li, Jianhua; An, Yulin; Zhang, Shuiwen

    2015-10-01

    Androgens have essential roles in the regulation of follicular development and female fertility. Androgen excess is the leading defect in polycystic ovary syndrome (PCOS) patients and involved in the ovarian dysfunction. The aim of this study was to elucidate the regarding regulatory role of androgen in the follicular development of female mouse. Immunohistochemical staining and Western blot analyses were performed to detect androgen receptor (AR) and Connexin 43 (Cx43) expression in ovaries from both control and testosterone-treated group mice. In this study, localizations of AR and Cx43 were dramatically altered in testosterone-treated mouse ovaries. In addition, AR expression was significantly increased, whereas Cx43 expression was markedly decreased after testosterone treatment. Alterations of AR and Cx43 expression by testosterone with concomitant reduction of MII oocytes. Overall, these results suggest the involvement of androgen in the regulation of AR and Cx43 localizations in mouse ovary. Alterations of AR and Cx43 expression by testosterone may affect normal folliculogenesis. Together these findings will enable us to begin understanding the important roles of AR and Cx43 actions in the regulation of follicular development, as well as providing insights into the role of AR and Cx43 actions in the androgen-associated reproductive diseases such as PCOS. PMID:26206424

  15. Androgens induce sebaceous differentiation in sebocyte cells expressing a stable functional androgen receptor.

    PubMed

    Barrault, Christine; Garnier, Julien; Pedretti, Nathalie; Cordier-Dirikoc, Sevda; Ratineau, Emeline; Deguercy, Alain; Bernard, François-Xavier

    2015-08-01

    Androgens act through non-genomic and androgen receptor (AR)-dependent genomic mechanisms. AR is expressed in the sebaceous gland and the importance of androgens in the sebaceous function is well established. However, the in vitro models used to date have failed to evidence a clear genomic effect (e.g., modification of gene expression profile) of androgens on human sebocyte cells. In order to study the impact of active androgens in sebocytes, we constructed a stable human sebocyte cell line derived from SEBO662 [17] constitutively expressing a fully functional AR. In these SEBO662 AR+ cells, dihydrotestosterone (DHT) induced AR nuclear translocation and the strong modulation of a set of transcripts (RASD1, GREB1...) known to be androgen-sensitive in other androgenic cells and tissues. Moreover, we observed that DHT precociously down-regulated markers for immature follicular cells (KRT15, TNC) and for hair lineage (KRT75, FST) and up-regulated the expression of genes potentially related to sebocyte differentiation (MUC1/EMA, AQP3, FADS2). These effects were fully confirmed at the protein level. In addition, DHT-stimulated SEBO662 AR+, cultured in a low-calcium defined keratinocyte medium without serum or any complement, neosynthesize lipids, including sebum lipids, and store increased amounts of triglycerides in lipid droplets. DHT also induces morphological changes, increases cell size, and treatments over 7 days lead to a time-dependent increase in the population of apoptotic DNA-fragmented cells. Taken together, these results show for the first time that active androgens alone can engage immature sebocytes in a clear lipogenic differentiation process (Graphical abstract). These effects depend on the expression of a functional AR in these cells. This model should be of interest for revisiting the mechanisms of the sebaceous function in vitro and for the design of relevant pharmacological models for drug or compound testing. PMID:25864624

  16. Identification of a novel androgen receptor agonist (or “androgen mimic”) of environmental concern: spironolactone

    EPA Science Inventory

    Spironolactone is a pharmaceutical that acts as an androgen receptor (AR) antagonist in humans to treat certain conditions such as hirsutism, various dermatologic afflictions, and female pattern hair loss. The drug is also used to treat hypertension as a diuretic. With this commo...

  17. Antioxidants Abrogate Alpha-Tocopherylquinone-Mediated Down-Regulation of the Androgen Receptor in Androgen-Responsive Prostate Cancer Cells

    PubMed Central

    Fajardo, Alexandra M.; MacKenzie, Debra A.; Olguin, Sarah L.; Scariano, John K.; Rabinowitz, Ian; Thompson, Todd A.

    2016-01-01

    Tocopherylquinone (TQ), the oxidation product of alpha-tocopherol (AT), is a bioactive molecule with distinct properties from AT. In this study, AT and TQ are investigated for their comparative effects on growth and androgenic activity in prostate cancer cells. TQ potently inhibited the growth of androgen-responsive prostate cancer cell lines (e.g., LAPC4 and LNCaP cells), whereas the growth of androgen-independent prostate cancer cells (e.g., DU145 cells) was not affected by TQ. Due to the growth inhibitory effects induced by TQ on androgen-responsive cells, the anti-androgenic properties of TQ were examined. TQ inhibited the androgen-induced activation of an androgen-responsive reporter and inhibited the release of prostate specific antigen from LNCaP cells. TQ pretreatment was also found to inhibit AR activation as measured using the Multifunctional Androgen Receptor Screening assay. Furthermore, TQ decreased androgen-responsive gene expression, including TM4SF1, KLK2, and PSA over 5-fold, whereas AT did not affect the expression of androgen-responsive genes. Of importance, the antiandrogenic effects of TQ on prostate cancer cells were found to result from androgen receptor protein down-regulation produced by TQ that was not observed with AT treatment. Moreover, none of the androgenic endpoints assessed were affected by AT. The down-regulation of androgen receptor protein by TQ was abrogated by co-treatment with antioxidants. Overall, the biological actions of TQ were found to be distinct from AT, where TQ was found to be a potent inhibitor of cell growth and androgenic activity in androgen-responsive prostate cancer cells. PMID:26986969

  18. Enhanced evaluation of selective androgen receptor modulators in vivo.

    PubMed

    Otto-Duessel, M; He, M; Adamson, T W; Jones, J O

    2013-01-01

    Selective androgen receptor modulators (SARMs) are a class of drugs that control the activity of the androgen receptor (AR), which mediates the response to androgens, in a tissue-selective fashion. They are specifically designed to reduce the possible complications that result from the systemic inhibition or activation of AR in patients with diseases that involve androgen signalling. However, there are no ideal in vivo models for evaluating candidate SARMs. Therefore, we created a panel of androgen-responsive genes in clinically relevant AR expressing tissues including prostate, skin, bone, fat, muscle, brain and kidney. We used select genes from this panel to compare transcriptional changes in response to the full agonist dihydrotestosterone (DHT) and the SARM bolandiol at 16 h and 6 weeks. We identified several genes in each tissue whose expression at each of these time points correlates with the known tissue-specific effects of these compounds. For example, in the prostate we found four genes whose expression was much lower in animals treated with bolandiol compared with animals treated with DHT for 6 weeks, which correlated well with differences in prostate weight. We demonstrate that adding molecular measurements (androgen-regulated gene expression) to the traditional physiological measurements (tissue weights, etc.) makes the evaluation of potential SARMs more accurate, thorough and perhaps more rapid by allowing measurement of selectivity after only 16 h of drug treatment. PMID:23258627

  19. Optimizing Ligand Efficiency of Selective Androgen Receptor Modulators (SARMs).

    PubMed

    Handlon, Anthony L; Schaller, Lee T; Leesnitzer, Lisa M; Merrihew, Raymond V; Poole, Chuck; Ulrich, John C; Wilson, Joseph W; Cadilla, Rodolfo; Turnbull, Philip

    2016-01-14

    A series of selective androgen receptor modulators (SARMs) containing the 1-(trifluoromethyl)benzyl alcohol core have been optimized for androgen receptor (AR) potency and drug-like properties. We have taken advantage of the lipophilic ligand efficiency (LLE) parameter as a guide to interpret the effect of structural changes on AR activity. Over the course of optimization efforts the LLE increased over 3 log units leading to a SARM 43 with nanomolar potency, good aqueous kinetic solubility (>700 μM), and high oral bioavailability in rats (83%). PMID:26819671

  20. Cryptotanshinone Suppresses Androgen Receptor-mediated Growth in Androgen Dependent and Castration Resistant Prostate Cancer Cells

    PubMed Central

    Xu, Defeng; Lin, Tzu-Hua; Li, Shaoshun; Da, Jun; Wen, Xing-Qiao; Ding, Jiang; Chang, Chawnshang; Yeh, Shuyuan

    2012-01-01

    Androgen receptor (AR) is the major therapeutic target for the treatment of prostate cancer (PCa). Anti-androgens to reduce or prevent androgens binding to AR are widely used to suppress AR-mediated PCa growth; however, the androgen depletion therapy is only effective for a period of time. Here we found a natural product/Chinese herbal medicine cryptotanshinone (CTS), with a structure similar to dihydrotestosterone (DHT), can effectively inhibit the DHT-induced AR transactivation and prostate cancer cell growth. Our results indicated that 0.5 µM CTS effectively suppresses the growth of AR-positive PCa cells, but has little effect on AR negative PC-3 cells and non-malignant prostate epithelial cells. Furthermore, our data indicated that CTS could modulate AR transactivation and suppress the DHT-mediated AR target genes (PSA, TMPRSS2, and TMEPA1) expression in both androgen responsive PCa LNCaP cells and castration resistant CWR22rv1 cells. Importantly, CTS selective inhibits AR without repressing the activities of other nuclear receptors, including ERα, GR, and PR. The mechanistic studies indicate that CTS functions as an AR inhibitor to suppress androgen/AR-mediated cell growth and PSA expression by blocking AR dimerization and the AR–coregulator complex formation. Furthermore, we showed that CTS effectively inhibits CWR22Rv1 cell growth in the xenograft animal model. The previously un-described mechanisms of CTS may explain how CTS inhibits the growth of PCa cells and help us to establish new therapeutic concepts for the treatment of PCa. PMID:22154085

  1. Mutational analysis of the androgen receptor gene in two Chinese families with complete androgen insensitivity syndrome

    PubMed Central

    WANG, SONG; XU, HAIKUN; AN, WEI; ZHU, DECHUN; LI, DEJUN

    2016-01-01

    Androgens are essential for normal male sex differentiation and are responsible for the normal development of male secondary sexual characteristics at puberty. The physiological effects of androgens are mediated by the androgen receptor (AR). Mutations in the AR gene are the most common cause of androgen insensitivity syndrome. The present study undertook a genetic analysis of the AR gene in two unrelated families affected by complete androgen insensitivity syndrome (CAIS) in China. In family 1, a previously reported nonsense mutation (G-to-A; p.W751X) was identified in exon 5 of the AR gene. In addition, a novel missense mutation was detected in exon 6 of the AR gene from family 2; this mutation resulted in a predicted amino acid change from phenylalanine to serine at codon 804 (T-to-C; p.F804S) in the ligand-binding domain (LBD) of AR. Computer simulation of the structural changes generated by the p.F804S substitution revealed marked conformational alterations in the hydrophobic core responsible for the stability and function of the AR-LBD. In conclusion, the present study identified two mutations from two unrelated Chinese families affected by CAIS. The novel mutation (p.F804S) may provide insights into the molecular mechanism underlying CAIS. Furthermore, it expands on the number of mutational hot spots in the international AR mutation database, which may be useful in the future for prenatal diagnosis and genetic counseling. PMID:27284311

  2. Androgen receptor roles in hepatocellular carcinoma, cirrhosis, and hepatitis

    PubMed Central

    Ma, Wen-Lung; Lai, Hsueh-Chou; Yeh, Shuyuan; Cai, Xiujun; Chang, Chawnshang

    2014-01-01

    Summary Androgen/androgen receptor (AR) signaling plays important roles in normal liver function and in progression of liver diseases. In studies of non-cancerous liver diseases, AR knockout mouse models of liver disease have revealed that androgen/AR signaling suppresses the development of steatosis, virus-related hepatitis, and cirrhosis. In addition, studies have shown that targeting AR in bone marrow-derived mesenchymal stem cells (BM-MSCs) improves their self-renewal and migration potentials, thereby increasing the efficacy of BM-MSC transplantation as a way to control the progression of cirrhosis. Androgen/AR signaling is known to be involved in the initiation of carcinogen- or Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). However, studies have demonstrated that AR, rather than androgen, plays the dominant role in cancer initiation. Therefore, targeting AR might be an appropriate therapy for patients with early-stage HCC. In contrast, androgen/AR signaling has been shown to suppress metastasis of HCC in patients with late-stage disease. In addition, there is evidence that therapy comprising Sorafenib and agents that enhance the functional expression of AR may suppress the progression of late-stage HCC. PMID:24424503

  3. Androgen receptor and histone lysine demethylases in ovine placenta.

    PubMed

    Cleys, Ellane R; Halleran, Jennifer L; Enriquez, Vanessa A; da Silveira, Juliano C; West, Rachel C; Winger, Quinton A; Anthony, Russell V; Bruemmer, Jason E; Clay, Colin M; Bouma, Gerrit J

    2015-01-01

    Sex steroid hormones regulate developmental programming in many tissues, including programming gene expression during prenatal development. While estradiol is known to regulate placentation, little is known about the role of testosterone and androgen signaling in placental development despite the fact that testosterone rises in maternal circulation during pregnancy and in placenta-induced pregnancy disorders. We investigated the role of testosterone in placental gene expression, and focused on androgen receptor (AR). Prenatal androgenization decreased global DNA methylation in gestational day 90 placentomes, and increased placental expression of AR as well as genes involved in epigenetic regulation, angiogenesis, and growth. As AR complexes with histone lysine demethylases (KDMs) to regulate AR target genes in human cancers, we also investigated if the same mechanism is present in the ovine placenta. AR co-immunoprecipitated with KDM1A and KDM4D in sheep placentomes, and AR-KDM1A complexes were recruited to a half-site for androgen response element (ARE) in the promoter region of VEGFA. Androgenized ewes also had increased cotyledonary VEGFA. Finally, in human first trimester placental samples KDM1A and KDM4D immunolocalized to the syncytiotrophoblast, with nuclear KDM1A and KDM4D immunostaining also present in the villous stroma. In conclusion, placental androgen signaling, possibly through AR-KDM complex recruitment to AREs, regulates placental VEGFA expression. AR and KDMs are also present in first trimester human placenta. Androgens appear to be an important regulator of trophoblast differentiation and placental development, and aberrant androgen signaling may contribute to the development of placental disorders. PMID:25675430

  4. ANDROGEN RECEPTOR ANTAGONISM BY THE ORGANOPHOSPHATE INSECTICIDE FENITROTHION

    EPA Science Inventory

    Androgen receptor antagonism by the organophosphate insecticide fenitrothion. Tamura, H., Maness, S.C., Reischmann, K. Dorman, D.C., Gray, L.E., and Gaido, K.W. (2000). Toxicol. Sci.

    Organophosphate insecticides represent one of the most widely used classes of pesticide...

  5. Nonsteroidal Androgen Receptor Ligands: Versatile Syntheses and Biological Data

    PubMed Central

    2012-01-01

    We report herein a stereoselective and straightforward methodology for the synthesis of new androgen receptor ligands with (anti)-agonistic activities. Oxygen–nitrogen replacement in bicalutamide-like structures paves the way to the disclosure of a new class of analogues, including cyclized/nitrogen-substituted derivatives, with promising antiandrogen (or anabolic) activity. PMID:24900495

  6. Alternative splicing of the androgen receptor in polycystic ovary syndrome.

    PubMed

    Wang, Fangfang; Pan, Jiexue; Liu, Ye; Meng, Qing; Lv, Pingping; Qu, Fan; Ding, Guo-Lian; Klausen, Christian; Leung, Peter C K; Chan, Hsiao Chang; Yao, Weimiao; Zhou, Cai-Yun; Shi, Biwei; Zhang, Junyu; Sheng, Jianzhong; Huang, Hefeng

    2015-04-14

    Polycystic ovary syndrome (PCOS) is one of the most common female endocrine disorders and a leading cause of female subfertility. The mechanism underlying the pathophysiology of PCOS remains to be illustrated. Here, we identify two alternative splice variants (ASVs) of the androgen receptor (AR), insertion and deletion isoforms, in granulosa cells (GCs) in ∼62% of patients with PCOS. AR ASVs are strongly associated with remarkable hyperandrogenism and abnormalities in folliculogenesis, and are absent from all control subjects without PCOS. Alternative splicing dramatically alters genome-wide AR recruitment and androgen-induced expression of genes related to androgen metabolism and folliculogenesis in human GCs. These findings establish alternative splicing of AR in GCs as the major pathogenic mechanism for hyperandrogenism and abnormal folliculogenesis in PCOS. PMID:25825716

  7. Enhanced Evaluation of Selective Androgen Receptor Modulators In Vivo

    PubMed Central

    Otto-Duessel, Maya; He, Miaoling; Adamson, Trinka W.; Jones, Jeremy O.

    2014-01-01

    Selective AR modulators (SARMs) are a class of drugs that control the activity of the androgen receptor (AR), which mediates the response to androgens, in a tissue-selective fashion. They are specifically designed to reduce the possible complications that result from the systemic inhibition or activation of AR in patients with diseases that involve androgen signaling. However, there are no ideal in vivo models for evaluating candidate SARMs. Therefore, we created a panel of androgen responsive genes in clinically-relevant AR expressing tissues including prostate, skin, bone, fat, muscle, brain, and kidney. We used select genes from this panel to compare transcriptional changes in response to the full agonist dihydrotestosterone (DHT) and the SARM bolandiol at 16h and 6wks. We identified several genes in each tissue whose expression at each of these time points correlates with the known tissue-specific effects of these compounds. For example, in the prostate we found four genes whose expression was much lower in animals treated with bolandiol compared to animals treated with DHT for 6wks, which correlated well with differences in prostate weight. We demonstrate that adding molecular measurements (androgen regulated gene expression) to the traditional physiological measurements (tissue weights, etc) makes the evaluation of potential SARMs more accurate, thorough, and perhaps more rapid by allowing measurement of selectivity after only 16 hours of drug treatment. PMID:23258627

  8. Cooperative demethylation by JMJD2C and LSD1 promotes androgen receptor-dependent gene expression.

    PubMed

    Wissmann, Melanie; Yin, Na; Müller, Judith M; Greschik, Holger; Fodor, Barna D; Jenuwein, Thomas; Vogler, Christine; Schneider, Robert; Günther, Thomas; Buettner, Reinhard; Metzger, Eric; Schüle, Roland

    2007-03-01

    Posttranslational modifications of histones, such as methylation, regulate chromatin structure and gene expression. Recently, lysine-specific demethylase 1 (LSD1), the first histone demethylase, was identified. LSD1 interacts with the androgen receptor and promotes androgen-dependent transcription of target genes by ligand-induced demethylation of mono- and dimethylated histone H3 at Lys 9 (H3K9) only. Here, we identify the Jumonji C (JMJC) domain-containing protein JMJD2C as the first histone tridemethylase regulating androgen receptor function. JMJD2C interacts with androgen receptor in vitro and in vivo. Assembly of ligand-bound androgen receptor and JMJD2C on androgen receptor-target genes results in demethylation of trimethyl H3K9 and in stimulation of androgen receptor-dependent transcription. Conversely, knockdown of JMJD2C inhibits androgen-induced removal of trimethyl H3K9, transcriptional activation and tumour cell proliferation. Importantly, JMJD2C colocalizes with androgen receptor and LSD1 in normal prostate and in prostate carcinomas. JMJD2C and LSD1 interact and both demethylases cooperatively stimulate androgen receptor-dependent gene transcription. In addition, androgen receptor, JMJD2C and LSD1 assemble on chromatin to remove methyl groups from mono, di and trimethylated H3K9. Thus, our data suggest that specific gene regulation requires the assembly and coordinate action of demethylases with distinct substrate specificities. PMID:17277772

  9. Androgen Receptor Structure, Function and Biology: From Bench to Bedside

    PubMed Central

    Davey, Rachel A; Grossmann, Mathis

    2016-01-01

    The actions of androgens such as testosterone and dihydrotestosterone are mediated via the androgen receptor (AR), a ligand-dependent nuclear transcription factor and member of the steroid hormone nuclear receptor family. Given its widespread expression in many cells and tissues, the AR has a diverse range of biological actions including important roles in the development and maintenance of the reproductive, musculoskeletal, cardiovascular, immune, neural and haemopoietic systems. AR signalling may also be involved in the development of tumours in the prostate, bladder, liver, kidney and lung. Androgens can exert their actions via the AR in a DNA binding-dependent manner to regulate target gene transcription, or in a non-DNA binding-dependent manner to initiate rapid, cellular events such as the phosphorylation of 2nd messenger signalling cascades. More recently, ligand-independent actions of the AR have also been identified. Given the large volume of studies relating to androgens and the AR, this review is not intended as an extensive review of all studies investigating the AR, but rather as an overview of the structure, function, signalling pathways and biology of the AR as well as its important role in clinical medicine, with emphasis on recent developments in this field. PMID:27057074

  10. Androgen Receptor Repression of GnRH Gene Transcription

    PubMed Central

    Brayman, Melissa J.; Pepa, Patricia A.; Berdy, Sara E.

    2012-01-01

    Alterations in androgen levels lead to reproductive defects in both males and females, including hypogonadotropic hypogonadism, anovulation, and infertility. Androgens have been shown to down-regulate GnRH mRNA levels through an androgen receptor (AR)-dependent mechanism. Here, we investigate how androgen regulates expression from the GnRH regulatory region in the GT1-7 cell line, a model of GnRH neurons. A synthetic androgen, R1881, repressed transcription from the GnRH promoter (GnRH-P) in an AR-dependent manner, and liganded AR associated with the chromatin at the GnRH-P in live GT1-7 cells. The three known octamer-binding transcription factor-1 (Oct-1) binding sites in GnRH-P were required for AR-mediated repression, although other sequences were also involved. Although a multimer of the consensus Oct-1 binding site was not repressed, a multimer of the cluster of Oct-1, Pre-B cell leukemia transcription factor (Pbx)/Prep, and NK2 homeobox 1 (Nkx2.1) binding sites, found at −106/−91 in GnRH-P, was sufficient for repression. In fact, overexpression of any of these factors disrupted the androgen response, indicating that a balance of factors in this tripartite complex is required for AR repression. AR bound to this region in EMSA, indicating a direct interaction of AR with DNA or with other transcription factors bound to GnRH-P at this sequence. Collectively, our data demonstrate that GnRH transcription is repressed by AR via multiple sequences in GnRH-P, including three Oct-1 binding sites, and that this repression requires the complex interaction of several transcription factors. PMID:22074952

  11. Classical androgen receptors in non-classical sites in the brain

    PubMed Central

    Sarkey, Sara; Azcoitia, Iñigo; Garcia-Segura, Luis Miguel; Garcia-Ovejero, Daniel; DonCarlos, Lydia L.

    2008-01-01

    Androgen receptors are expressed in many different neuronal populations in the central nervous system where they often act as transcription factors in the cell nucleus. However, recent studies have detected androgen receptor immunoreactivity in neuronal and glial processes of the adult rat neocortex, hippocampal formation, and amygdala as well as in the telencephalon of Eastern Fence and green anole lizards. This review discusses previously published findings on extranuclear androgen receptors, as well as new experimental results that begin to establish a possible functional role for androgen receptors in axons within cortical regions. Electron microscopic studies have revealed that androgen receptor immunoreactive processes in the rat brain correspond to axons, dendrites and glial processes. New results show that lesions of the dorsal CA1 region by local administration of ibotenic acid reduce the density of androgen receptor immunoreactive axons in the cerebral cortex and the amygdala, suggesting that these axons may originate in the hippocampus. Androgen receptor immunoreactivity in axons is also decreased by the intracerebroventricular administration of colchicine, suggesting that androgen receptor protein is transported from the perikaryon to the axons by fast axonal transport. Androgen receptors in axons located in the cerebral cortex and amygdala and originating in the hippocampus may play an important role in the rapid behavioral effects of androgens. PMID:18402960

  12. Selective androgen receptor modulators in preclinical and clinical development

    PubMed Central

    Narayanan, Ramesh; Mohler, Michael L.; Bohl, Casey E.; Miller, Duane D.; Dalton, James T.

    2008-01-01

    Androgen receptor (AR) plays a critical role in the function of several organs including primary and accessory sexual organs, skeletal muscle, and bone, making it a desirable therapeutic target. Selective androgen receptor modulators (SARMs) bind to the AR and demonstrate osteo- and myo-anabolic activity; however, unlike testosterone and other anabolic steroids, these nonsteroidal agents produce less of a growth effect on prostate and other secondary sexual organs. SARMs provide therapeutic opportunities in a variety of diseases, including muscle wasting associated with burns, cancer, or end-stage renal disease, osteoporosis, frailty, and hypogonadism. This review summarizes the current standing of research and development of SARMs, crystallography of AR with SARMs, plausible mechanisms for their action and the potential therapeutic indications for this emerging class of drugs. PMID:19079612

  13. Splice Variants of Androgen Receptor and Prostate Cancer

    PubMed Central

    Caffo, Orazio; Maines, Francesca; Veccia, Antonello; Kinspergher, Stefania; Galligioni, Enzo

    2016-01-01

    Over the last ten years, two new-generation hormonal drugs and two chemotherapeutic agents have been approved for the treatment of metastatic castration-resistant prostate cancer. Unfortunately, some patients have primary resistance to them and the others eventually develop secondary resistance. It has recently been suggested that the presence of androgen receptor splice variants plays a leading role in the primary and secondary resistance to the new hormonal drugs, whereas their presence seem to have only a partial effect on the activity of the chemotherapeutic agents. The aim of this paper is to review the published data concerning the role of androgen receptor splice variants in prostate cancer biology, and their potential use as biomarkers when making therapeutic decisions.

  14. Discovery of aryloxy tetramethylcyclobutanes as novel androgen receptor antagonists.

    PubMed

    Guo, Chuangxing; Linton, Angelica; Kephart, Susan; Ornelas, Martha; Pairish, Mason; Gonzalez, Javier; Greasley, Samantha; Nagata, Asako; Burke, Benjamin J; Edwards, Martin; Hosea, Natilie; Kang, Ping; Hu, Wenyue; Engebretsen, Jon; Briere, David; Shi, Manli; Gukasyan, Hovik; Richardson, Paul; Dack, Kevin; Underwood, Toby; Johnson, Patrick; Morell, Andrew; Felstead, Robert; Kuruma, Hidetoshi; Matsimoto, Hiroaki; Zoubeidi, Amina; Gleave, Martin; Los, Gerrit; Fanjul, Andrea N

    2011-11-10

    An aryloxy tetramethylcyclobutane was identified as a novel template for androgen receptor (AR) antagonists via cell-based high-throughput screening. Follow-up to the initial "hit" established 5 as a viable lead. Further optimization to achieve full AR antagonism led to the discovery of 26 and 30, both of which demonstrated excellent in vivo tumor growth inhibition upon oral administration in a castration-resistant prostate cancer (CRPC) animal model. PMID:21936524

  15. Nonsteroidal Selective Androgen Receptor Modulators Enhance Female Sexual Motivation

    PubMed Central

    Jones, Amanda; Hwang, Dong Jin; Duke, Charles B.; He, Yali; Siddam, Anjaiah; Miller, Duane D.

    2010-01-01

    Women experience a decline in estrogen and androgen levels after natural or surgically induced menopause, effects that are associated with a loss of sexual desire and bone mineral density. Studies in our laboratories have shown the beneficial effects of selective androgen receptor modulators (SARMs) in the treatment of osteoporosis and muscle wasting in animal models. A series of S-3-(phenoxy)-2-hydroxy-2-methyl-N-(4-cyano-3-trifluoromethyl-phenyl)-propionamide analogs was synthesized to evaluate the effects of B-ring substitutions on in vitro and in vivo pharmacologic activity, especially female sexual motivation. The androgen receptor (AR) relative binding affinities ranged from 0.1 to 26.5% (relative to dihydrotestosterone) and demonstrated a range of agonist activity at 100 nM. In vivo pharmacologic activity was first assessed by using male rats. Structural modifications to the B-ring significantly affected the selectivity of the SARMs, demonstrating that single-atom substitutions can dramatically and unexpectedly influence activity in androgenic (i.e., prostate) and anabolic (i.e., muscle) tissues. (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro,4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide (S-23) displayed full agonist activity in androgenic and anabolic tissues; however, the remaining SARMs were more prostate-sparing, selectively maintaining the size of the levator ani muscle in castrated rats. The partner-preference paradigm was used to evaluate the effects of SARMs on female sexual motivation. With the exception of two four-halo substituted analogs, the SARMs increased sexual motivation in ovariectomized rats, with potency and efficacy comparable with testosterone propionate. These results indicate that the AR is important in regulating female libido given the nonaromatizable nature of SARMs and it could be a superior alternative to steroidal testosterone preparations in the treatment of hypoactive sexual desire disorder. PMID:20444881

  16. Binding properties of androgen receptors. Evidence for identical receptors in rat testis, epididymis, and prostate.

    PubMed

    Wilson, E M; French, F S

    1976-09-25

    Androgen receptors in crude and partially purified 105,000 X g supernatant fractions from rat testis, epididymis, and prostate were studied in vitro using a charcoal adsorption assay and sucrose gradient centrifugation. Androgen metabolism was eliminated during receptor purification allowing determination of the kinetics of [3H]-androgen-receptor complex formation. In all three tissues, receptors were found to have essentially identical capabilities to bind androgen, with the affinity for [3H] dihydrotestosterone being somewhat higher than for [3H] testosterone. Equilibrium dissociation constants for [3H] dihydrotestosterone and [3H] testosterone (KD = 2 to 5 X 10(-10) M) were estimated from independently determined rates of association (ka congruent to 6 X 10(7) M-1 h-1 for [3H] dihydrotestosterone and 2 X 10(8) M-1 h-1 for [3H] testosterone) and dissociation (t 1/2 congruent to 40 hr for [3H] dihydrotestosterone and 15 h [3H] testosterone). Evaluation of the effect of temperature on androgen receptor binding of [3H]testosterone allowed estimation of several thermodynamic parameters, including activation energies of association and dissociation (delta H congruent to 14 kcal/mol), the apparent free energy (delta G congruent to -12 kcal/mol), enthalpy (delta H congruent to -2.5 kcal/mol), and entropy (delta S congruent to 35 cal col-1 K-1). Optimum receptor binding occurred at a pH of 8. Receptor stability was greatly enhanced when bound with androgen. Receptor specificity for testosterone and dihydrotestosterone was demonstrated by competitive binding assays. The potent synthetic androgen, 7 alpha, 17 alpha-dimethyl-19-nortestosterone, inhibited binding of [3H] testosterone or [3H] dihydrotesterone nearly as well as testosterone and dihydrotestosterone while larger amounts of 5 alpha-androstane-3alpha, 17 beta-diol and nonandrogenic steroids were required. Sedimentation coefficients of androgen receptors in all unfractionated supernatants were 4 and 5 to 8 S

  17. Protein phosphatase 1 suppresses androgen receptor ubiquitylation and degradation.

    PubMed

    Liu, Xiaming; Han, Weiwei; Gulla, Sarah; Simon, Nicholas I; Gao, Yanfei; Cai, Changmeng; Yang, Hongmei; Zhang, Xiaoping; Liu, Jihong; Balk, Steven P; Chen, Shaoyong

    2016-01-12

    The phosphoprotein phosphatases are emerging as important androgen receptor (AR) regulators in prostate cancer (PCa). We reported previously that the protein phosphatase 1 catalytic subunit (PP1α) can enhance AR activity by dephosphorylating a site in the AR hinge region (Ser650) and thereby decrease AR nuclear export. In this study we show that PP1α increases the expression of wildtype as well as an S650A mutant AR, indicating that it is acting through one or more additional mechanisms. We next show that PP1α binds primarily to the AR ligand binding domain and decreases its ubiquitylation and degradation. Moreover, we find that the PP1α inhibitor tautomycin increases phosphorylation of AR ubiquitin ligases including SKP2 and MDM2 at sites that enhance their activity, providing a mechanism by which PP1α may suppress AR degradation. Significantly, the tautomycin mediated decrease in AR expression was most pronounced at low androgen levels or in the presence of the AR antagonist enzalutamide. Consistent with this finding, the sensitivity of LNCaP and C4-2 PCa cells to tautomycin, as assessed by PSA synthesis and proliferation, was enhanced at low androgen levels or by treatment with enzalutamide. Together these results indicate that PP1α may contribute to stabilizing AR protein after androgen deprivation therapies, and that targeting PP1α or the AR-PP1α interaction may be effective in castration-resistant prostate cancer (CRPC). PMID:26636645

  18. The liver X receptor agonist T0901317 acts as androgen receptor antagonist in human prostate cancer cells

    SciTech Connect

    Chuu, Chih-pin; Chen, Rou-Yu; Hiipakka, Richard A.; Kokontis, John M.; Warner, Karen V.; Xiang, Jialing; Liao, Shutsung . E-mail: sliao@uchicago.edu

    2007-06-01

    T0901317 is a potent non-steroidal synthetic liver X receptor (LXR) agonist. T0901317 blocked androgenic stimulation of the proliferation of androgen-dependent LNCaP 104-S cells and androgenic suppression of the proliferation of androgen-independent LNCaP 104-R2 cells, inhibited the transcriptional activation of an androgen-dependent reporter gene by androgen, and suppressed gene and protein expression of prostate specific antigen (PSA), a target gene of androgen receptor (AR) without affecting gene and protein expression of AR. T0901317 also inhibited binding of a radiolabeled androgen to AR, but inhibition was much weaker compared to the effect of the antiandrogens, bicalutamide and hydroxyflutamide. The LXR agonist T0901317, therefore, acts as an antiandrogen in human prostate cancer cells.

  19. Androgens.

    PubMed

    Iyer, Rakesh; Handelsman, David J

    2016-01-01

    Androgen abuse is the most potent and prevalent form of sports doping detected. It originated from the early years of the Cold War as an epidemic confined to drug cheating within elite power sports. In the decades following the end of the Cold War, it has become disseminated into an endemic based within the illicit drug subcultures serving recreational abusers seeking cosmetic body sculpting effects. Within sports, both direct androgen abuse (administration of androgens), as well as indirect androgen abuse (administration of nonandrogenic drugs to increase endogenous testosterone), is mostly readily detectable with mass spectrometry-based anti-doping urine tests. The ongoing temptation of fame and fortune and the effectiveness of androgen abuse in power sports continue to entice cheating via renewed approaches aiming to exploit androgens. These require ongoing vigilance, inventiveness in anti-doping science, and targeting coaches as well as athletes in order to build resilience against doping and maintain fairness in elite sport. The challenge of androgen abuse in the community among recreational abusers has barely been recognized and effective approaches remain to be developed. PMID:27347677

  20. Expression of androgen receptor splice variants in clinical breast cancers

    PubMed Central

    Dvinge, Heidi; Tarulli, Gerard A.; Hanson, Adrienne R.; Ryan, Natalie K.; Pickering, Marie A.; Birrell, Stephen N.; Hu, Dong Gui; Mackenzie, Peter I.; Russell, Roslin; Caldas, Carlos; Raj, Ganesh V.; Dehm, Scott M.; Plymate, Stephen R.; Bradley, Robert K.; Tilley, Wayne D.; Selth, Luke A.

    2015-01-01

    The importance of androgen receptor (AR) signaling is increasingly being recognized in breast cancer, which has elicited clinical trials aimed at assessing the efficacy of androgen deprivation therapy (ADT) for metastatic disease. In prostate cancer, resistance to ADT is frequently associated with the emergence of androgen-independent splice variants of the AR (AR variants, AR-Vs) that lack the LBD and are constitutively active. Women with breast cancer may be prone to a similar phenomenon. Herein, we show that in addition to the prototypical transcript, the AR gene produces a diverse range of AR-V transcripts in primary breast tumors. The most frequently and highly expressed variant was AR-V7 (exons 1/2/3/CE3), which was detectable at the mRNA level in > 50% of all breast cancers and at the protein level in a subset of ERα-negative tumors. Functionally, AR-V7 is a constitutively active and ADT-resistant transcription factor that promotes growth and regulates a transcriptional program distinct from AR in ERα-negative breast cancer cells. Importantly, we provide ex vivo evidence that AR-V7 is upregulated by the AR antagonist enzalutamide in primary breast tumors. These findings have implications for treatment response in the ongoing clinical trials of ADT in breast cancer. PMID:26554309

  1. Expression of androgen receptor splice variants in clinical breast cancers.

    PubMed

    Hickey, Theresa E; Irvine, Connie M; Dvinge, Heidi; Tarulli, Gerard A; Hanson, Adrienne R; Ryan, Natalie K; Pickering, Marie A; Birrell, Stephen N; Hu, Dong Gui; Mackenzie, Peter I; Russell, Roslin; Caldas, Carlos; Raj, Ganesh V; Dehm, Scott M; Plymate, Stephen R; Bradley, Robert K; Tilley, Wayne D; Selth, Luke A

    2015-12-29

    The importance of androgen receptor (AR) signaling is increasingly being recognized in breast cancer, which has elicited clinical trials aimed at assessing the efficacy of androgen deprivation therapy (ADT) for metastatic disease. In prostate cancer, resistance to ADT is frequently associated with the emergence of androgen-independent splice variants of the AR (AR variants, AR-Vs) that lack the LBD and are constitutively active. Women with breast cancer may be prone to a similar phenomenon. Herein, we show that in addition to the prototypical transcript, the AR gene produces a diverse range of AR-V transcripts in primary breast tumors. The most frequently and highly expressed variant was AR-V7 (exons 1/2/3/CE3), which was detectable at the mRNA level in > 50% of all breast cancers and at the protein level in a subset of ERα-negative tumors. Functionally, AR-V7 is a constitutively active and ADT-resistant transcription factor that promotes growth and regulates a transcriptional program distinct from AR in ERα-negative breast cancer cells. Importantly, we provide ex vivo evidence that AR-V7 is upregulated by the AR antagonist enzalutamide in primary breast tumors. These findings have implications for treatment response in the ongoing clinical trials of ADT in breast cancer. PMID:26554309

  2. Nonneural Androgen Receptors Affect Sexual Differentiation of Brain and Behavior.

    PubMed

    Swift-Gallant, Ashlyn; Coome, Lindsay A; Ramzan, Firyal; Monks, D Ashley

    2016-02-01

    Testosterone, acting via estrogenic and androgenic pathways, is the major endocrine mechanism promoting sexual differentiation of the mammalian nervous system and behavior, but we have an incomplete knowledge of which cells and tissues mediate these effects. To distinguish between neural and nonneural actions of androgens in sexual differentiation of brain and behavior, we generated a loxP-based transgenic mouse, which overexpresses androgen receptors (ARs) when activated by Cre. We used this transgene to overexpress AR globally in all tissues using a cytomegalovirus (CMV)-Cre driver (CMV-AR), and we used a Nestin-Cre driver to overexpress AR only in neural tissue (Nes-AR). We then examined whether neural or global AR overexpression can affect socio-sexual behaviors using a resident-intruder paradigm. We found that both neural and global AR overexpression resulted in decreased aggressive behaviors and increased thrusting during mounting of intruders, consistent with a neural site of action. Global, but not neural, AR overexpression in males led to an increase in same-sex anogenital investigation. Together, these results suggest novel roles for nonneural AR in sexual differentiation of mice, and indicate that excess AR can lead to a paradoxical reduction of male-typical behavior. PMID:26636184

  3. Minoxidil may suppress androgen receptor-related functions.

    PubMed

    Hsu, Cheng-Lung; Liu, Jai-Shin; Lin, An-Chi; Yang, Chih-Hsun; Chung, Wen-Hung; Wu, Wen-Guey

    2014-04-30

    Although minoxidil has been used for more than two decades to treat androgenetic alopecia (AGA), an androgen-androgen receptor (AR) pathway-dominant disease, its precise mechanism of action remains elusive. We hypothesized that minoxidil may influence the AR or its downstream signaling. These tests revealed that minoxidil suppressed AR-related functions, decreasing AR transcriptional activity in reporter assays, reducing expression of AR targets at the protein level, and suppressing AR-positive LNCaP cell growth. Dissecting the underlying mechanisms, we found that minoxidil interfered with AR-peptide, AR-coregulator, and AR N/C-terminal interactions, as well as AR protein stability. Furthermore, a crystallographic analysis using the AR ligand-binding domain (LBD) revealed direct binding of minoxidil to the AR in a minoxidil-AR-LBD co-crystal model, and surface plasmon resonance assays demonstrated that minoxidil directly bound the AR with a K(d) value of 2.6 µM. Minoxidil also suppressed AR-responsive reporter activity and decreased AR protein stability in human hair dermal papilla cells. The current findings provide evidence that minoxidil could be used to treat both cancer and age-related disease, and open a new avenue for applications of minoxidil in treating androgen-AR pathway-related diseases. PMID:24742982

  4. Minoxidil may suppress androgen receptor-related functions

    PubMed Central

    Hsu, Cheng-Lung; Liu, Jai-Shin; Lin, An-Chi; Yang, Chih-Hsun; Chung, Wen-Hung; Wu, Wen-Guey

    2014-01-01

    Although minoxidil has been used for more than two decades to treat androgenetic alopecia (AGA), an androgen-androgen receptor (AR) pathway-dominant disease, its precise mechanism of action remains elusive. We hypothesized that minoxidil may influence the AR or its downstream signaling. These tests revealed that minoxidil suppressed AR-related functions, decreasing AR transcriptional activity in reporter assays, reducing expression of AR targets at the protein level, and suppressing AR-positive LNCaP cell growth. Dissecting the underlying mechanisms, we found that minoxidil interfered with AR-peptide, AR-coregulator, and AR N/C-terminal interactions, as well as AR protein stability. Furthermore, a crystallographic analysis using the AR ligand-binding domain (LBD) revealed direct binding of minoxidil to the AR in a minoxidil-AR-LBD co-crystal model, and surface plasmon resonance assays demonstrated that minoxidil directly bound the AR with a Kd value of 2.6 μM. Minoxidil also suppressed AR-responsive reporter activity and decreased AR protein stability in human hair dermal papilla cells. The current findings provide evidence that minoxidil could be used to treat both cancer and age-related disease, and open a new avenue for applications of minoxidil in treating androgen-AR pathway-related diseases. PMID:24742982

  5. Molecular cloning and characterization of a nuclear androgen receptor activated by 11-ketotestosterone

    PubMed Central

    Olsson, Per-Erik; Berg, A Håkan; von Hofsten, Jonas; Grahn, Birgitta; Hellqvist, Anna; Larsson, Anders; Karlsson, Johnny; Modig, Carina; Borg, Bertil; Thomas, Peter

    2005-01-01

    Although 11-ketotestosterone is a potent androgen and induces male secondary sex characteristics in many teleosts, androgen receptors with high binding affinity for 11-ketotestosterone or preferential activation by 11-ketotestosterone have not been identified. So, the mechanism by which 11-ketotestosterone exhibits such high potency remains unclear. Recently we cloned the cDNA of an 11-ketotestosterone regulated protein, spiggin, from three-spined stickleback renal tissue. As spiggin is the only identified gene product regulated by 11-ketotestosterone, the stickleback kidney is ideal for determination of the mechanism of 11-ketotestosterone gene regulation. A single androgen receptor gene with two splicing variants, belonging to the androgen receptor-β subfamily was cloned from stickleback kidney. A high affinity, saturable, single class of androgen specific binding sites, with the characteristics of an androgen receptor, was identified in renal cytosolic and nuclear fractions. Measurement of ligand binding moieties in the cytosolic and nuclear fractions as well as to the recombinant receptor revealed lower affinity for 11-ketotestosterone than for dihydrotestosterone. Treatment with different androgens did not up-regulate androgen receptor mRNA level or increase receptor abundance, suggesting that auto-regulation is not involved in differential ligand activation. However, comparison of the trans-activation potential of the stickleback androgen receptor with the human androgen receptor, in both human HepG2 cells and zebrafish ZFL cells, revealed preferential activation by 11-ketotestosterone of the stickleback receptor, but not of the human receptor. These findings demonstrate the presence of a receptor preferentially activated by 11-ketotestosterone in the three-spined stickleback, so far the only one known in any animal. PMID:16107211

  6. Contributions of sex, testosterone, and androgen receptor CAG repeat number to virtual Morris water maze performance.

    PubMed

    Nowak, Nicole T; Diamond, Michael P; Land, Susan J; Moffat, Scott D

    2014-03-01

    The possibility that androgens contribute to the male advantage typically found on measures of spatial cognition has been investigated using a variety of approaches. To date, evidence to support the notion that androgens affect spatial cognition in healthy young adults is somewhat equivocal. The present study sought to clarify the association between testosterone (T) and spatial performance by extending measurements of androgenicity to include both measures of circulating T as well as an androgen receptor-specific genetic marker. The aims of this study were to assess the contributions of sex, T, and androgen receptor CAG repeat number (CAGr) on virtual Morris water task (vMWT) performance in a group of healthy young men and women. The hypothesis that men would outperform women on vMWT outcomes was supported. Results indicate that CAGr may interact with T to impact navigation performance and suggest that consideration of androgen receptor sensitivity is an important consideration in evaluating hormone-behavior relationships. PMID:24495604

  7. Androgen receptor targeted therapies in castration-resistant prostate cancer: Bench to clinic.

    PubMed

    Imamura, Yusuke; Sadar, Marianne D

    2016-08-01

    The androgen receptor is a transcription factor and validated therapeutic target for prostate cancer. Androgen deprivation therapy remains the gold standard treatment, but it is not curative, and eventually the disease will return as lethal castration-resistant prostate cancer. There have been improvements in the therapeutic landscape with new agents approved, such as abiraterone acetate, enzalutamide, sipuleucel-T, cabazitaxel and Ra-223, in the past 5 years. New insight into the mechanisms of resistance to treatments in advanced disease is being and has been elucidated. All current androgen receptor-targeting therapies inhibit the growth of prostate cancer by blocking the ligand-binding domain, where androgen binds to activate the receptor. Persuasive evidence supports the concept that constitutively active androgen receptor splice variants lacking the ligand-binding domain are one of the resistant mechanisms underlying advanced disease. Transcriptional activity of the androgen receptor requires a functional AF-1 region in its N-terminal domain. Preclinical evidence proved that this domain is a druggable target to forecast a potential paradigm shift in the management of advanced prostate cancer. This review presents an overview of androgen receptor-related mechanisms of resistance as well as novel therapeutic agents to overcome resistance that is linked to the expression of androgen receptor splice variants in castration-resistant prostate cancer. PMID:27302572

  8. Advantages and Limitations of Androgen Receptor-Based Methods for Detecting Anabolic Androgenic Steroid Abuse as Performance Enhancing Drugs

    PubMed Central

    Bailey, Kathy; Yazdi, Tahmineh; Masharani, Umesh; Tyrrell, Blake; Butch, Anthony; Schaufele, Fred

    2016-01-01

    Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete’s urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as ‘T-equivalent’ concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact. PMID:26998755

  9. Advantages and Limitations of Androgen Receptor-Based Methods for Detecting Anabolic Androgenic Steroid Abuse as Performance Enhancing Drugs.

    PubMed

    Bailey, Kathy; Yazdi, Tahmineh; Masharani, Umesh; Tyrrell, Blake; Butch, Anthony; Schaufele, Fred

    2016-01-01

    Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete's urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as 'T-equivalent' concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact. PMID:26998755

  10. Androgen receptor functions in castration-resistant prostate cancer and mechanisms of resistance to new agents targeting the androgen axis

    PubMed Central

    Yuan, X; Cai, C; Chen, S; Chen, S; Yu, Z; Balk, SP

    2016-01-01

    The metabolic functions of androgen receptor (AR) in normal prostate are circumvented in prostate cancer (PCa) to drive tumor growth, and the AR also can acquire new growth-promoting functions during PCa development and progression through genetic and epigenetic mechanisms. Androgen deprivation therapy (ADT, surgical or medical castration) is the standard treatment for metastatic PCa, but patients invariably relapse despite castrate androgen levels (castration-resistant PCa, CRPC). Early studies from many groups had shown that AR was highly expressed and transcriptionally active in CRPC, and indicated that steroids from the adrenal glands were contributing to this AR activity. More recent studies showed that CRPC cells had increased expression of enzymes mediating androgen synthesis from adrenal steroids, and could synthesize androgens de novo from cholesterol. Phase III clinical trials showing a survival advantage in CRPC for treatment with abiraterone (inhibitor of the enzyme CYP17A1 required for androgen synthesis that markedly reduces androgens and precursor steroids) and for enzalutamide (new AR antagonist) have now confirmed that AR activity driven by residual androgens makes a major contribution to CRPC, and led to the recent Food and Drug Administration approval of both agents. Unfortunately, patients treated with these agents for advanced CRPC generally relapse within a year and AR appears to be active in the relapsed tumors, but the molecular mechanisms mediating intrinsic or acquired resistance to these AR-targeted therapies remain to be defined. This review outlines AR functions that contribute to PCa development and progression, the roles of intratumoral androgen synthesis and AR structural alterations in driving AR activity in CRPC, mechanisms of action for abiraterone and enzalutamide, and possible mechanisms of resistance to these agents. PMID:23752196

  11. STANDARDIZATION AND VALIDATION OF PROPOSED PROTOCOLS FOR IN VITRO SCREENING ASSAYS AND QSAR FOR ESTROGEN RECEPTOR AND ANDROGEN RECEPTOR

    EPA Science Inventory

    Screening EDCs for androgenic and antiandrogenic activities was recommended by the EDSTAC Committee in it Final Report. This research will develop in vitro approaches to assess estrogen receptor binding, develop cell lines that stably express estrogen receptor for screening EDC...

  12. Modulation of the cytosolic androgen receptor in striated muscle by sex steroids

    NASA Technical Reports Server (NTRS)

    Rance, N. E.; Max, S. E.

    1982-01-01

    The influence of orchiectomy (GDX) and steroid administration on the level of the cytosolic androgen receptor in the rat levator ani muscle and in rat skeletal muscles (tibialis anterior and extensor digitorum longus) was studied. Androgen receptor binding to muscle cytosol was measured using H-3 methyltrienolone (R1881) as ligand, 100 fold molar excess unlabeled R1881 to assess nonspecific binding, and 500 fold molar excess of triamcinolone acetonide to prevent binding to glucocorticoid and progestin receptors. Results demonstrate that modification of the levels of sex steroids can alter the content of androgen receptors of rat striated muscle. Data suggest that: (1) cytosolic androgen receptor levels increase after orchiectomy in both levator ani muscle and skeletal muscle; (2) the acute increase in receptor levels is blocked by an inhibitor of protein synthesis; and (3) administration of estradiol-17 beta to castrated animals increases receptor binding in levator ani muscle but not in skeletal muscle.

  13. Sensitization of androgen refractory prostate cancer cells to anti-androgens through re-expression of epigenetically repressed androgen receptor - Synergistic action of quercetin and curcumin.

    PubMed

    Sharma, Vikas; Kumar, Lokesh; Mohanty, Sujit K; Maikhuri, Jagdamba P; Rajender, Singh; Gupta, Gopal

    2016-08-15

    Epigenetic repression of Androgen Receptor (AR) gene by hypermethylation of its promoter causes resistance in prostate cancer (CaP) to androgen deprivation therapy with anti-androgens. Some dietary phytocompounds like quercetin (Q) and curcumin (C) with reported DNMT-inhibitory activity were tested for their ability to re-express the AR in AR-negative CaP cell lines PC3 and DU145. Combined treatment with Q+C was much more effective than either Q or C in inhibiting DNMT, causing global hypomethylation, restoring AR mRNA and protein levels and causing apoptosis via mitochondrial depolarization of PC3 and DU145. The functional AR protein expressed in Q+C treated cells sensitized them to dihydrotestosterone (DHT)-induced proliferation, bicalutamide-induced apoptosis, bound to androgen response element to increase luciferase activity in gene reporter assay and was susceptible to downregulation by AR siRNA. Bisulfite sequencing revealed high methylation of AR promoter CpG sites in AR-negative DU145 and PC3 cell lines that was significantly demethylated by Q+C treatment, which restored AR expression. Notable synergistic effects of Q+C combination in re-sensitizing androgen refractory CaP cells to AR-mediated apoptosis, their known safety in clinical use, and epidemiological evidences relating their dietary consumption with lower cancer incidences indicate their potential for use in chemoprevention of androgen resistance in prostate cancer. PMID:27132804

  14. Selective androgen receptor modulator activity of a steroidal antiandrogen TSAA-291 and its cofactor recruitment profile.

    PubMed

    Hikichi, Yukiko; Yamaoka, Masuo; Kusaka, Masami; Hara, Takahito

    2015-10-15

    Selective androgen receptor modulators (SARMs) specifically bind to the androgen receptor and exert agonistic or antagonistic effects on target organs. In this study, we investigated the SARM activity of TSAA-291, previously known as a steroidal antiandrogen, in mice because TSAA-291 was found to possess partial androgen receptor agonist activity in reporter assays. In addition, to clarify the mechanism underlying its tissue selectivity, we performed comprehensive cofactor recruitment analysis of androgen receptor using TSAA-291 and dihydrotestosterone (DHT), an endogenous androgen. The androgen receptor agonistic activity of TSAA-291 was more obvious in reporter assays using skeletal muscle cells than in those using prostate cells. In castrated mice, TSAA-291 increased the weight of the levator ani muscle without increasing the weight of the prostate and seminal vesicle. Comprehensive cofactor recruitment analysis via mammalian two-hybrid methods revealed that among a total of 112 cofactors, 12 cofactors including the protein inhibitor of activated STAT 1 (PIAS1) were differently recruited to androgen receptor in the presence of TSAA-291 and DHT. Prostate displayed higher PIAS1 expression than skeletal muscle. Forced expression of the PIAS1 augmented the transcriptional activity of the androgen receptor, and silencing of PIAS1 by siRNAs suppressed the secretion of prostate-specific antigen, an androgen responsive marker. Our results demonstrate that TSAA-291 has SARM activity and suggest that TSAA-291 may induce different conformational changes of the androgen receptor and recruitment profiles of cofactors such as PIAS1, compared with DHT, to exert tissue-specific activity. PMID:26335395

  15. Bisphenol A affects androgen receptor function via multiple mechanisms

    PubMed Central

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B. Alex; Jetten, Anton M.; Austin, Christopher, P.; Tice, Raymond R.

    2013-01-01

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. PMID:23562765

  16. Bisphenol A affects androgen receptor function via multiple mechanisms.

    PubMed

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B Alex; Jetten, Anton M; Austin, Christopher P; Tice, Raymond R

    2013-05-25

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. PMID:23562765

  17. Identification of novel genes that regulate androgen receptor signaling and growth of androgen-deprived prostate cancer cells

    PubMed Central

    Levina, Elina; Ji, Hao; Chen, Mengqiang; Baig, Mirza; Oliver, David; Ohouo, Patrice; Lim, Chang-uk; Schools, Garry; Carmack, Steven; Ding, Ye; Broude, Eugenia V.; Roninson, Igor B.

    2015-01-01

    Prostate cancer progression to castration refractory disease is associated with anomalous transcriptional activity of the androgen receptor (AR) in an androgen-depleted milieu. To identify novel gene products whose downregulation transactivates AR in prostate cancer cells, we performed a screen of enzymatically-generated shRNA lenti-libraries selecting for transduced LNCaP cells with elevated expression of a fluorescent reporter gene under the control of an AR-responsive promoter. The shRNAs present in selected populations were analyzed using high-throughput sequencing to identify target genes. Highly enriched gene targets were then validated with siRNAs against selected genes, testing first for increased expression of luciferase from an AR-responsive promoter and then for altered expression of endogenous androgen-regulated genes in LNCaP cells. We identified 20 human genes whose silencing affected the expression of exogenous and endogenous androgen-responsive genes in prostate cancer cells grown in androgen-depleted medium. Knockdown of four of these genes upregulated the expression of endogenous AR targets and siRNAs targeting two of these genes (IGSF8 and RTN1) enabled androgen-independent proliferation of androgen-dependent cells. The effects of IGSF8 appear to be mediated through its interaction with a tetraspanin protein, CD9, previously implicated in prostate cancer progression. Remarkably, homozygous deletions of IGSF8 are found almost exclusively in prostate cancers but not in other cancer types. Our study shows that androgen independence can be achieved through the inhibition of specific genes and reveals a novel set of genes that regulate AR signaling in prostate cancers. PMID:26036626

  18. The PPAR{gamma} ligand ciglitazone regulates androgen receptor activation differently in androgen-dependent versus androgen-independent human prostate cancer cells

    SciTech Connect

    Moss, Patrice E.; Lyles, Besstina E.; Stewart, LaMonica V.

    2010-12-10

    The androgen receptor (AR) regulates growth and progression of androgen-dependent as well as androgen-independent prostate cancer cells. Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) agonists have been reported to reduce AR activation in androgen-dependent LNCaP prostate cancer cells. To determine whether PPAR{gamma} ligands are equally effective at inhibiting AR activity in androgen-independent prostate cancer, we examined the effect of the PPAR{gamma} ligands ciglitazone and rosiglitazone on C4-2 cells, an androgen- independent derivative of the LNCaP cell line. Luciferase-based reporter assays and Western blot analysis demonstrated that PPAR{gamma} ligand reduced dihydrotestosterone (DHT)-induced increases in AR activity in LNCaP cells. However, in C4-2 cells, these compounds increased DHT-induced AR driven luciferase activity. In addition, ciglitazone did not significantly alter DHT-mediated increases in prostate specific antigen (PSA) protein or mRNA levels within C4-2 cells. siRNA-based experiments demonstrated that the ciglitazone-induced regulation of AR activity observed in C4-2 cells was dependent on the presence of PPAR{gamma}. Furthermore, overexpression of the AR corepressor cyclin D1 inhibited the ability of ciglitazone to induce AR luciferase activity in C4-2 cells. Thus, our data suggest that both PPAR{gamma} and cyclin D1 levels influence the ability of ciglitazone to differentially regulate AR signaling in androgen-independent C4-2 prostate cancer cells.

  19. Steroid-induced androgen receptor-oestradiol receptor beta-Src complex triggers prostate cancer cell proliferation.

    PubMed

    Migliaccio, A; Castoria, G; Di Domenico, M; de Falco, A; Bilancio, A; Lombardi, M; Barone, M V; Ametrano, D; Zannini, M S; Abbondanza, C; Auricchio, F

    2000-10-16

    Treatment of human prostate carcinoma-derived LNCaP cells with androgen or oestradiol triggers simultaneous association of androgen receptor and oestradiol receptor beta with Src, activates the Src/Raf-1/Erk-2 pathway and stimulates cell proliferation. Surprisingly, either androgen or oestradiol action on each of these steps is inhibited by both anti-androgens and anti-oestrogens. Similar findings for oestradiol receptor alpha were observed in MCF-7 or T47D cells stimulated by either oestradiol or androgens. Microinjection of LNCaP, MCF-7 and T47D cells with SrcK(-) abolishes steroid-stimulated S-phase entry. Data from transfected Cos cells confirm and extend the findings from these cells. Hormone-stimulated Src interaction with the androgen receptor and oestradiol receptor alpha or beta is detected using glutathione S:-transferase fusion constructs. Src SH2 interacts with phosphotyrosine 537 of oestradiol receptor alpha and the Src SH3 domain with a proline-rich stretch of the androgen receptor. The role of this phosphotyrosine is stressed by its requirement for association of oestradiol receptor alpha with Src and consequent activation of Src in intact Cos cells. PMID:11032808

  20. Different types of androgen receptor mutations in patients with complete androgen insensitivity syndrome.

    PubMed

    Shao, Jialiang; Hou, Jiangang; Li, Bingkun; Li, Dongyang; Zhang, Ning; Wang, Xiang

    2015-02-01

    Mutations of androgen receptor (AR) are the most frequent cause of 46, XY disorders of sex development and associated with a variety of phenotypes, ranging from phenotypic women (complete androgen insensitivity syndrome (CAIS)) to milder degrees of undervirilization (partial form or PAIS) or men with only infertility (mild form or MAIS). From 2009 to 2012, two young Chinese female individuals with CAIS from two families were referred to our hospital due to primary amenorrhea. Defects in testosterone (T) and dihydrotestosterone (DHT) synthesis were excluded. Physical examination revealed that the patients have normal female external genitalia, normal breast development, vellus hair in the axilla and on the arms and legs, but absence of pubic hair, and a blind-ending vagina. Two different types of AR mutations have been detected by sequencing of genomic DNA: Family A showed deletion of exon 2 in AR gene; Family B showed a single nucleotide C-to-T transition in exon 8 of AR gene resulting in a proline 893-to-leucine substitution (Pro893Leu). Testicular histology showed developmental immaturity of seminiferous tubules with the absence of spermatogenic cells or spermatozoa. No AR immunoreactivity was observed in either case. Three adult patients recovered well from bilateral orchiectomy. The juvenile patient of family B was followed up. Our present study on these two families revealed two different types of AR mutation. The definitive diagnosis of AIS was based on clinical examination and genetic investigations. Our findings verified the mechanism of CAIS and also enriched AR Gene Mutation Database. PMID:25674389

  1. Promoter-dependent activity on androgen receptor N-terminal domain mutations in androgen insensitivity syndrome.

    PubMed

    Tadokoro-Cuccaro, Rieko; Davies, John; Mongan, Nigel P; Bunch, Trevor; Brown, Rosalind S; Audi, Laura; Watt, Kate; McEwan, Iain J; Hughes, Ieuan A

    2014-01-01

    Androgen receptor (AR) mutations are associated with androgen insensitivity syndrome (AIS). Missense mutations identified in the AR-N-terminal domain (AR-NTD) are rare, and clinical phenotypes are typically mild. We investigated 7 missense mutations and 2 insertion/deletions located in the AR-NTD. This study aimed to elucidate the pathogenic role of AR-NTD mutants in AIS and to use this knowledge to further define AR-NTD function. AR-NTD mutations (Q120E, A159T, G216R, N235K, G248V, L272F, and P380R) were introduced into AR-expression plasmids. Stably expressing cell lines were established for del57L and ins58L. Transactivation was measured using luciferase reporter constructs under the control of GRE and Pem promoters. Intrinsic fluorescence spectroscopy and partial proteolysis studies were performed for mutations which showed reduced activities by using a purified AR-AF1 protein. Pem-luciferase reporter activation was reduced for A159T, N235K, and G248V but not the GRE-luciferase reporter. Protein structure analysis detected no significant change in the AR-AF1 region for these mutations. Reduced cellular expression and transactivation activity were observed for ins58L. The mutations Q120E, G216R, L272F, P380R, and del57L showed small or no detectable changes in function. Thus, clinical and experimental analyses have identified novel AR-signalling defects associated with mutations in the structurally disordered AR-NTD domain in patients with AIS. PMID:25500996

  2. Quantitative Proteomic Profiles of Androgen Receptor Signaling in the Liver of Fathead Minnows Pimephalus promelas

    EPA Science Inventory

    Androgenic chemicals are present in the environment at concentrations that impair reproductive processes in fish. The objective of this experiment was to identify proteins altered by an androgen receptor agonist (17â-trenbolone) and antagonist (flutamide) in the liver. Female fa...

  3. Targeting of androgen receptor in bone reveals a lack of androgen anabolic action and inhibition of osteogenesis A model for compartment-specific androgen action in the skeleton

    PubMed Central

    Wiren, Kristine M.; Semirale, Anthony A.; Zhang, Xiao-Wei; Woo, Adrian; Tommasini, Steven M.; Price, Christopher; Schaffler, Mitchell B.; Jepsen, Karl J.

    2008-01-01

    Androgens are anabolic hormones that affect many tissues, including bone. However, an anabolic effect of androgen treatment on bone in eugonadal subjects has not been observed and clinical trials have been disappointing. The androgen receptor (AR) mediates biological responses to androgens. In bone tissue, both AR and the estrogen receptor (ER) are expressed. Since androgens can be converted into estrogen, the specific role of the AR in maintenance of skeletal homoeostasis remains controversial. The goal of this study was to use skeletally targeted overexpression of AR in differentiated osteoblasts as a means of elucidating the specific role(s) for AR transactivation in the mature bone compartment. Transgenic mice overexpressing AR under the control of the 2.3-kb α1(I)-collagen promoter fragment showed no difference in body composition, testosterone, or 17β-estradiol levels. However, transgenic males have reduced serum osteocalcin, CTx and TRAPC5b levels, and a bone phenotype was observed. In cortical bone, high-resolution micro-computed tomography revealed no difference in periosteal perimeter but a significant reduction in cortical bone area due to an enlarged marrow cavity. Endocortical bone formation rate was also significantly inhibited. Biomechanical analyses showed decreased whole bone strength and quality, with significant reductions in all parameters tested. Trabecular morphology was altered, with increased bone volume comprised of more trabeculae that were closer together but not thicker. Expression of genes involved in bone formation and bone resorption was significantly reduced. The consequences of androgen action are compartment-specific; anabolic effects are exhibited exclusively at periosteal surfaces, but in mature osteoblasts androgens inhibited osteogenesis with detrimental effects on matrix quality, bone fragility and whole bone strength. Thus, the present data demonstrate that enhanced androgen signaling targeted to bone results in low bone

  4. Recognition and Accommodation at the Androgen Receptor Coactivator Binding Interface

    PubMed Central

    Hur, Eugene; Pfaff, Samuel J; Payne, E. Sturgis; Grøn, Hanne; Buehrer, Benjamin M

    2004-01-01

    Prostate cancer is a leading killer of men in the industrialized world. Underlying this disease is the aberrant action of the androgen receptor (AR). AR is distinguished from other nuclear receptors in that after hormone binding, it preferentially responds to a specialized set of coactivators bearing aromatic-rich motifs, while responding poorly to coactivators bearing the leucine-rich “NR box” motifs favored by other nuclear receptors. Under normal conditions, interactions with these AR-specific coactivators through aromatic-rich motifs underlie targeted gene transcription. However, during prostate cancer, abnormal association with such coactivators, as well as with coactivators containing canonical leucine-rich motifs, promotes disease progression. To understand the paradox of this unusual selectivity, we have derived a complete set of peptide motifs that interact with AR using phage display. Binding affinities were measured for a selected set of these peptides and their interactions with AR determined by X-ray crystallography. Structures of AR in complex with FxxLF, LxxLL, FxxLW, WxxLF, WxxVW, FxxFF, and FxxYF motifs reveal a changing surface of the AR coactivator binding interface that permits accommodation of both AR-specific aromatic-rich motifs and canonical leucine-rich motifs. Induced fit provides perfect mating of the motifs representing the known family of AR coactivators and suggests a framework for the design of AR coactivator antagonists. PMID:15328534

  5. Localization of androgen receptors and estrogen receptors in the same cells of the songbird brain

    SciTech Connect

    Gahr, M. )

    1990-12-01

    Estrogens and androgens each have unique effects but act together for the neural differentiation and control of sexual behaviors in male vertebrates, such as the canary. The neuronal basis for these synergistic effects is elusive because the spatial relation between estrogen target cells and androgen target cells is unknown. This study localized estrogen receptor (ER)-containing cells by using immunocytochemistry and androgen receptor (AR)-containing cells by using autoradiography in the same sections of the male canary brain. Three cell types, those containing only ER, those containing only AR, and those containing both ER and AR, were found in tissue-specific frequencies. The midbrain nucleus intercollicularis exhibited the highest number of cells expressing both ER and AR, whereas ER and AR are expressed only in disjunctive cell populations in the forebrain nucleus hyperstriatalis ventrale, pars caudale. Synergistic effects of androgens and estrogens for the neural behavorial control could result from cells containing both ER and AR (intracellular) and from neural circuits containing ER and AR in different cells (intercellular).

  6. Regulators of Androgen Action Resource: a one-stop shop for the comprehensive study of androgen receptor action.

    PubMed

    DePriest, Adam D; Fiandalo, Michael V; Schlanger, Simon; Heemers, Frederike; Mohler, James L; Liu, Song; Heemers, Hannelore V

    2016-01-01

    Androgen receptor (AR) is a ligand-activated transcription factor that is the main target for treatment of non-organ-confined prostate cancer (CaP). Failure of life-prolonging AR-targeting androgen deprivation therapy is due to flexibility in steroidogenic pathways that control intracrine androgen levels and variability in the AR transcriptional output. Androgen biosynthesis enzymes, androgen transporters and AR-associated coregulators are attractive novel CaP treatment targets. These proteins, however, are characterized by multiple transcript variants and isoforms, are subject to genomic alterations, and are differentially expressed among CaPs. Determining their therapeutic potential requires evaluation of extensive, diverse datasets that are dispersed over multiple databases, websites and literature reports. Mining and integrating these datasets are cumbersome, time-consuming tasks and provide only snapshots of relevant information. To overcome this impediment to effective, efficient study of AR and potential drug targets, we developed the Regulators of Androgen Action Resource (RAAR), a non-redundant, curated and user-friendly searchable web interface. RAAR centralizes information on gene function, clinical relevance, and resources for 55 genes that encode proteins involved in biosynthesis, metabolism and transport of androgens and for 274 AR-associated coregulator genes. Data in RAAR are organized in two levels: (i) Information pertaining to production of androgens is contained in a 'pre-receptor level' database, and coregulator gene information is provided in a 'post-receptor level' database, and (ii) an 'other resources' database contains links to additional databases that are complementary to and useful to pursue further the information provided in RAAR. For each of its 329 entries, RAAR provides access to more than 20 well-curated publicly available databases, and thus, access to thousands of data points. Hyperlinks provide direct access to gene

  7. Regulators of Androgen Action Resource: a one-stop shop for the comprehensive study of androgen receptor action

    PubMed Central

    Fiandalo, Michael V.; Schlanger, Simon; Heemers, Frederike; Mohler, James L.; Liu, Song; Heemers, Hannelore V.

    2016-01-01

    Androgen receptor (AR) is a ligand-activated transcription factor that is the main target for treatment of non-organ-confined prostate cancer (CaP). Failure of life-prolonging AR-targeting androgen deprivation therapy is due to flexibility in steroidogenic pathways that control intracrine androgen levels and variability in the AR transcriptional output. Androgen biosynthesis enzymes, androgen transporters and AR-associated coregulators are attractive novel CaP treatment targets. These proteins, however, are characterized by multiple transcript variants and isoforms, are subject to genomic alterations, and are differentially expressed among CaPs. Determining their therapeutic potential requires evaluation of extensive, diverse datasets that are dispersed over multiple databases, websites and literature reports. Mining and integrating these datasets are cumbersome, time-consuming tasks and provide only snapshots of relevant information. To overcome this impediment to effective, efficient study of AR and potential drug targets, we developed the Regulators of Androgen Action Resource (RAAR), a non-redundant, curated and user-friendly searchable web interface. RAAR centralizes information on gene function, clinical relevance, and resources for 55 genes that encode proteins involved in biosynthesis, metabolism and transport of androgens and for 274 AR-associated coregulator genes. Data in RAAR are organized in two levels: (i) Information pertaining to production of androgens is contained in a ‘pre-receptor level’ database, and coregulator gene information is provided in a ‘post-receptor level’ database, and (ii) an ‘other resources’ database contains links to additional databases that are complementary to and useful to pursue further the information provided in RAAR. For each of its 329 entries, RAAR provides access to more than 20 well-curated publicly available databases, and thus, access to thousands of data points. Hyperlinks provide direct access to

  8. Antiandrogens Act as Selective Androgen Receptor Modulators at the Proteome Level in Prostate Cancer Cells*

    PubMed Central

    Brooke, Greg N.; Gamble, Simon C.; Hough, Michael A.; Begum, Shajna; Dart, D. Alwyn; Odontiadis, Michael; Powell, Sue M.; Fioretti, Flavia M.; Bryan, Rosie A.; Waxman, Jonathan; Wait, Robin; Bevan, Charlotte L.

    2015-01-01

    Current therapies for prostate cancer include antiandrogens, inhibitory ligands of the androgen receptor, which repress androgen-stimulated growth. These include the selective androgen receptor modulators cyproterone acetate and hydroxyflutamide and the complete antagonist bicalutamide. Their activity is partly dictated by the presence of androgen receptor mutations, which are commonly detected in patients who relapse while receiving antiandrogens, i.e. in castrate-resistant prostate cancer. To characterize the early proteomic response to these antiandrogens we used the LNCaP prostate cancer cell line, which harbors the androgen receptor mutation most commonly detected in castrate-resistant tumors (T877A), analyzing alterations in the proteome, and comparing these to the effect of these therapeutics upon androgen receptor activity and cell proliferation. The majority are regulated post-transcriptionally, possibly via nongenomic androgen receptor signaling. Differences detected between the exposure groups demonstrate subtle changes in the biological response to each specific ligand, suggesting a spectrum of agonistic and antagonistic effects dependent on the ligand used. Analysis of the crystal structures of the AR in the presence of cyproterone acetate, hydroxyflutamide, and DHT identified important differences in the orientation of key residues located in the AF-2 and BF-3 protein interaction surfaces. This further implies that although there is commonality in the growth responses between androgens and those antiandrogens that stimulate growth in the presence of a mutation, there may also be influential differences in the growth pathways stimulated by the different ligands. This therefore has implications for prostate cancer treatment because tumors may respond differently dependent upon which mutation is present and which ligand is activating growth, also for the design of selective androgen receptor modulators, which aim to elicit differential proteomic

  9. Androgens downregulate miR-21 expression in breast cancer cells underlining the protective role of androgen receptor

    PubMed Central

    Donà, Ada; Rizza, Pietro; Aquila, Saveria; Avena, Paola; Lanzino, Marilena; Pellegrino, Michele; Vivacqua, Adele; Tucci, Paola; Morelli, Catia; Andò, Sebastiano; Sisci, Diego

    2016-01-01

    Although the protective role of androgen receptor (AR) in breast cancer (BC) is well established, the mechanisms involved remains largely unexplored. MicroRNAs play fundamental roles in many biological processes, including tumor cell development and metastasis. Herein, we report that androgens reduce BC cells proliferation acting as a negative modulator of the onco-miRNA-21. The synthetic androgen miboleron (Mib) decreases BC cell proliferation induced by miR-21 over-expression and AR knockdown evidenced the requirement of AR in the down-regulation of miR-21 expression. These effects seem to be a general mechanism occurring in BC tissues. Chromatin immune-precipitation (ChIP) analysis disclosed the binding of AR to a specific ARE sequence in miR-21 proximal promoter and recognizes the recruitment of HDAC3 as component for AR-mediated transcriptional repression. Such event is associated to a significantly reduced PolII binding in Mib treated extracts confirming that activated AR is a transcriptional repressor of miR-21 expression, providing further insight into the protective role of androgens in breast cancer cells. Collectively, our data and the widespread AR expression in primary and metastatic breast tumours, suggest a careful examination of the therapeutic potential of androgens also in potentiating the effectiveness of anti-oestrogen adjuvant therapies. PMID:26862856

  10. Androgens downregulate miR-21 expression in breast cancer cells underlining the protective role of androgen receptor.

    PubMed

    Casaburi, Ivan; Cesario, Maria Grazia; Donà, Ada; Rizza, Pietro; Aquila, Saveria; Avena, Paola; Lanzino, Marilena; Pellegrino, Michele; Vivacqua, Adele; Tucci, Paola; Morelli, Catia; Andò, Sebastiano; Sisci, Diego

    2016-03-15

    Although the protective role of androgen receptor (AR) in breast cancer (BC) is well established, the mechanisms involved remains largely unexplored. MicroRNAs play fundamental roles in many biological processes, including tumor cell development and metastasis. Herein, we report that androgens reduce BC cells proliferation acting as a negative modulator of the onco-miRNA-21.The synthetic androgen miboleron (Mib) decreases BC cell proliferation induced by miR-21 over-expression and AR knockdown evidenced the requirement of AR in the down-regulation of miR-21 expression. These effects seem to be a general mechanism occurring in BC tissues.Chromatin immune-precipitation (ChIP) analysis disclosed the binding of AR to a specific ARE sequence in miR-21 proximal promoter and recognizes the recruitment of HDAC3 as component for AR-mediated transcriptional repression. Such event is associated to a significantly reduced PolII binding in Mib treated extracts confirming that activated AR is a transcriptional repressor of miR-21 expression, providing further insight into the protective role of androgens in breast cancer cells.Collectively, our data and the widespread AR expression in primary and metastatic breast tumours, suggest a careful examination of the therapeutic potential of androgens also in potentiating the effectiveness of anti-oestrogen adjuvant therapies. PMID:26862856

  11. Prostate cancer stem cells: the role of androgen and estrogen receptors.

    PubMed

    Di Zazzo, Erika; Galasso, Giovanni; Giovannelli, Pia; Di Donato, Marzia; Di Santi, Annalisa; Cernera, Gustavo; Rossi, Valentina; Abbondanza, Ciro; Moncharmont, Bruno; Sinisi, Antonio Agostino; Castoria, Gabriella; Migliaccio, Antimo

    2016-01-01

    Prostate cancer is one of the most commonly diagnosed cancers in men, and androgen deprivation therapy still represents the primary treatment for prostate cancer patients. This approach, however, frequently fails and patients develop castration-resistant prostate cancer, which is almost untreatable.Cancer cells are characterized by a hierarchical organization, and stem/progenitor cells are endowed with tumor-initiating activity. Accumulating evidence indicates that prostate cancer stem cells lack the androgen receptor and are, indeed, resistant to androgen deprivation therapy. In contrast, these cells express classical (α and/or β) and novel (GPR30) estrogen receptors, which may represent new putative targets in prostate cancer treatment.In the present review, we discuss the still-debated mechanisms, both genomic and non-genomic, by which androgen and estradiol receptors (classical and novel) mediate the hormonal control of prostate cell stemness, transformation, and the continued growth of prostate cancer. Recent preclinical and clinical findings obtained using new androgen receptor antagonists, anti-estrogens, or compounds such as enhancers of androgen receptor degradation and peptides inhibiting non-genomic androgen functions are also presented. These new drugs will likely lead to significant advances in prostate cancer therapy. PMID:26506594

  12. Prostate cancer stem cells: the role of androgen and estrogen receptors

    PubMed Central

    Di Zazzo, Erika; Galasso, Giovanni; Giovannelli, Pia; Di Donato, Marzia; Di Santi, Annalisa; Cernera, Gustavo; Rossi, Valentina; Abbondanza, Ciro; Moncharmont, Bruno; Sinisi, Antonio Agostino; Castoria, Gabriella; Migliaccio, Antimo

    2016-01-01

    Prostate cancer is one of the most commonly diagnosed cancers in men, and androgen deprivation therapy still represents the primary treatment for prostate cancer patients. This approach, however, frequently fails and patients develop castration-resistant prostate cancer, which is almost untreatable. Cancer cells are characterized by a hierarchical organization, and stem/progenitor cells are endowed with tumor-initiating activity. Accumulating evidence indicates that prostate cancer stem cells lack the androgen receptor and are, indeed, resistant to androgen deprivation therapy. In contrast, these cells express classical (α and/or β) and novel (GPR30) estrogen receptors, which may represent new putative targets in prostate cancer treatment. In the present review, we discuss the still-debated mechanisms, both genomic and non-genomic, by which androgen and estradiol receptors (classical and novel) mediate the hormonal control of prostate cell stemness, transformation, and the continued growth of prostate cancer. Recent preclinical and clinical findings obtained using new androgen receptor antagonists, anti-estrogens, or compounds such as enhancers of androgen receptor degradation and peptides inhibiting non-genomic androgen functions are also presented. These new drugs will likely lead to significant advances in prostate cancer therapy. PMID:26506594

  13. Common molecular weight of the androgen receptor monomer in different target tissues

    SciTech Connect

    Johnson, M.P.; Young, C.Y.F.; Rowley, D.R.; Tindall, D.J.

    1987-06-02

    Previously reported molecular weights for the monomeric steroid binding subunit of the androgen receptor protein have ranged from 25,000 to 167,000. The molecular weight appeared to vary among different species and target organs, as well as between different investigators. This study has examined androgen receptors from a diverse group of organs and species to determine whether these tissues share a common monomeric form. Gel filtration revealed peaks of specific (/sup 3/H)dihydrotestosterone binding activity corresponding to Stokes radii of 54, 33, and 20 A in cytosols from several tissues. Phosphocellulose chromatography diminished the appearance of the smaller androgen receptor forms and facilitated the appearance of the larger 54-A form. Mixing experiments suggested that phosphocellulose was stabilizing the 54-A form by binding putative proteases which cleave this larger form. Methods were developed to generate homogeneous preparations of a given androgen receptor size for comparative study. Sucrose density gradient analysis showed sedimentation coefficients of 4.5-5.0, 3.5-4.0, and 2.5-3.0 S, respectively. The corresponding calculated molecular weights were 109,000-121,000, 52,000-59,000, and 22,000-27,000. Scatchard analysis of each of these androgen receptor forms demonstrated very similar affinity for (/sup 3/H)dihydrotestosterone. Extensively purified preparations of androgen receptor from R3327 tumor contained varying amounts of the three receptor forms even though molybdate and phosphocellulose were used to stabilize the androgen receptor protein during purification. It is concluded that androgen receptors from a variety of tissues share a common monomeric subunit and that stabilization is necessary during analytical and purification procedures to prevent cleavage of the monomer by endogenous proteases.

  14. Identification and Characterization of the Androgen Receptor From the American Alligator, Alligator mississippiensis

    PubMed Central

    Miyagawa, Shinichi; Yatsu, Ryohei; Kohno, Satomi; Doheny, Brenna M.; Ogino, Yukiko; Ishibashi, Hiroshi; Katsu, Yoshinao; Ohta, Yasuhiko; Guillette, Louis J.

    2015-01-01

    Androgens are essential for the development, reproduction, and health throughout the life span of vertebrates, particularly during the initiation and maintenance of male sexual characteristics. Androgen signaling is mediated by the androgen receptor (AR), a member of the steroid nuclear receptor superfamily. Mounting evidence suggests that environmental factors, such as exogenous hormones or contaminants that mimic hormones, can disrupt endocrine signaling and function. The American alligator (Alligator mississippiensis), a unique model for ecological research in that it exhibits environment-dependent sex determination, is oviparous and long lived. Alligators from a contaminated environment exhibit low reproductive success and morphological disorders of the testis and phallus in neonates and juveniles, both associated with androgen signaling; thus, the alterations are hypothesized to be related to disrupted androgen signaling. However, this line of research has been limited because of a lack of information on the alligator AR gene. Here, we isolated A mississippiensis AR homologs (AmAR) and evaluated receptor-hormone/chemical interactions using a transactivation assay. We showed that AmAR responded to all natural androgens and their effects were inhibited by cotreatment with antiandrogens, such as flutamide, p,p′-dichlorodiphenyldichloroethylene, and vinclozolin. Intriguingly, we found a spliced form of the AR from alligator cDNA, which lacks seven amino acids within the ligand-binding domain that shows no response to androgens. Finally, we have initial data on a possible dominant-negative function of the spliced form of the AR against androgen-induced AmAR. PMID:25974402

  15. Identification and Characterization of the Androgen Receptor From the American Alligator, Alligator mississippiensis.

    PubMed

    Miyagawa, Shinichi; Yatsu, Ryohei; Kohno, Satomi; Doheny, Brenna M; Ogino, Yukiko; Ishibashi, Hiroshi; Katsu, Yoshinao; Ohta, Yasuhiko; Guillette, Louis J; Iguchi, Taisen

    2015-08-01

    Androgens are essential for the development, reproduction, and health throughout the life span of vertebrates, particularly during the initiation and maintenance of male sexual characteristics. Androgen signaling is mediated by the androgen receptor (AR), a member of the steroid nuclear receptor superfamily. Mounting evidence suggests that environmental factors, such as exogenous hormones or contaminants that mimic hormones, can disrupt endocrine signaling and function. The American alligator (Alligator mississippiensis), a unique model for ecological research in that it exhibits environment-dependent sex determination, is oviparous and long lived. Alligators from a contaminated environment exhibit low reproductive success and morphological disorders of the testis and phallus in neonates and juveniles, both associated with androgen signaling; thus, the alterations are hypothesized to be related to disrupted androgen signaling. However, this line of research has been limited because of a lack of information on the alligator AR gene. Here, we isolated A mississippiensis AR homologs (AmAR) and evaluated receptor-hormone/chemical interactions using a transactivation assay. We showed that AmAR responded to all natural androgens and their effects were inhibited by cotreatment with antiandrogens, such as flutamide, p,p'-dichlorodiphenyldichloroethylene, and vinclozolin. Intriguingly, we found a spliced form of the AR from alligator cDNA, which lacks seven amino acids within the ligand-binding domain that shows no response to androgens. Finally, we have initial data on a possible dominant-negative function of the spliced form of the AR against androgen-induced AmAR. PMID:25974402

  16. Sequence variation in the androgen receptor gene is not a common determinant of male sexual orientation.

    PubMed Central

    Macke, J P; Hu, N; Hu, S; Bailey, M; King, V L; Brown, T; Hamer, D; Nathans, J

    1993-01-01

    To test the hypothesis that DNA sequence variation in the androgen receptor gene plays a causal role in the development of male sexual orientation, we have (1) measured the degree of concordance of androgen receptor alleles in 36 pairs of homosexual brothers, (2) compared the lengths of polyglutamine and polyglycine tracts in the amino-terminal domain of the androgen receptor in a sample of 197 homosexual males and 213 unselected subjects, and (3) screened the the entire androgen receptor coding region for sequence variation by PCR and denaturing gradient-gel electrophoresis (DGGE) and/or single-strand conformation polymorphism analysis in 20 homosexual males with homosexual or bisexual brothers and one homosexual male with no homosexual brothers, and screened the amino-terminal domain of the receptor for sequence variation in an additional 44 homosexual males, 37 of whom had one or more first- or second-degree male relatives who were either homosexual or bisexual. These analyses show that (1) homosexual brothers are as likely to be discordant as concordant for androgen receptor alleles; (2) there are no large-scale differences between the distributions of polyglycine or polyglutamine tract lengths in the homosexual and control groups; and (3) coding region sequence variation is not commonly found within the androgen receptor gene of homosexual men. The DGGE screen identified two rare amino acid substitutions, ser205-to-arg and glu793-to-asp, the biological significance of which is unknown. Images Figure 2 PMID:8213813

  17. Sequence variation in the androgen receptor gene is not a common determinant of male sexual orientation

    SciTech Connect

    Macke, J.P.; Nathans, J.; King, V.L. ); Hu, N.; Hu, S.; Hamer, D.; Bailey, M. ); Brown, T. )

    1993-10-01

    To test the hypothesis that DNA sequence variation in the androgen receptor gene plays a causal role in the development of male sexual orientation, the authors have (1) measured the degree of concordance of androgen receptor alleles in 36 pairs of homosexual brothers, (2) compared the lengths of polyglutamine and polyglycine tracts in the amino-terminal domain of the androgen receptor in a sample of 197 homosexual males and 213 unselected subjects, and (3) screened the entire androgen receptor coding region for sequence variation by PCR and denaturing gradient-gel electrophoresis (DGGE) and/or single-strand conformation polymorphism analysis in 20 homosexual males with homosexual or bisexual brothers and one homosexual male with no homosexual brothers, and screened the amino-terminal domain of the receptor for sequence variation in an additional 44 homosexual males, 37 of whom had one or more first- or second-degree male relatives who were either homosexual or bisexual. These analyses show that (1) homosexual brothers are as likely to be discordant as concordant for androgen receptor alleles; (2) there are no large-scale differences between the distributions of polyglycine or polyglutamine tract lengths in the homosexual and control groups; and (3) coding region sequence variation is not commonly found within the androgen receptor gene of homosexual men. The DGGE screen identified two rare amino acid substitutions, ser[sup 205] -to-arg and glu[sup 793]-to-asp, the biological significance of which is unknown. 32 refs., 2 figs., 2 tabs.

  18. Single strand conformation polymorphism analysis of androgen receptor gene mutations in patients with androgen insensitivity syndromes: Application for diagnosis, genetic counseling, and therapy

    SciTech Connect

    Hiort, O. Tufts-New England Medical Center, Boston, MA ); Huang, Q. ); Sinnecker, G.H.G.; Kruse, K. ); Sadeghi-Nejad, A.; Wolfe, H.J. ); Yandell, D.W. ) Harvard School of Public Health, Boston, MA )

    1993-07-01

    Recent studies indicate that mutations in the androgen receptor gene are associated with androgen insensitivity syndromes, a heterogeneous group of related disorders involving defective sexual differentiation in karyotypic males. In this report, the authors address the possibility of rapid mutational analysis of the androgen receptor gene for initial diagnosis, genetic counseling, and molecular subclassification of affected patients and their families. DNA from peripheral blood leukocytes of six patients from five families with various degrees of androgen insensitivity was studied. Exons 2 to 8 of the androgen receptor gene were analyzed using a combination of single strand conformation polymorphism analysis and direct DNA sequencing. Female family members were also studied to identify heterozygote carriers. Point mutations in the AR gene were identified in all six patients, and all mutations caused amino acid substitutions. One patient with incomplete androgen insensitivity was a mosaic for the mutation. Four of the five mothers, as well as a young sister of one patient, were carriers of the mutation present in the affected child. The data show that new mutations may occur in the androgen receptor gene leading to sporadic androgen insensitivity syndrome. Molecular genetic characterization of the variant allele can serve as a primary tool for diagnosis and subsequent therapy, and can provide a basis for distinguishing heterozygous carriers in familial androgen resistance. The identification of carriers is of substantial clinical importance for genetic counseling. 29 refs., 2 figs., 1 tab.

  19. INTERACTION OF ORGANOPHOSPHATE PESTICIDES AND RELATED COMPOUNDS WITH THE ANDROGEN RECEPTOR

    EPA Science Inventory

    Identification of several environmental chemicals capable of binding to the androgen receptor (AR) and interfering with its normal function has heightened concern for adverse effects across a broad spectrum of environmental chemicals. We previously demonstrated AR antagonist act...

  20. Honokiol Inhibits Androgen Receptor Activity in Prostate Cancer Cells

    PubMed Central

    Hahm, Eun-Ryeong; Karlsson, A. Isabella; Bonner, Michael Y.; Arbiser, Jack L.; Singh, Shivendra V.

    2014-01-01

    BACKGROUND We have shown previously that honokiol (HNK), a bioactive component of the medicinal plant Magnolia officinalis, inhibits growth of human prostate cancer cells in vitro and in vivo. However, the effect of HNK on androgen receptor (AR) signaling is not known. METHODS LNCaP, C4-2, and TRAMP-C1 cells were used for various assays. Trypan blue dye exclusion assay or clonogenic assay was performed for determination of cell viability. The effects of HNK and/or its analogs on protein levels of AR and its target gene product prostate specific antigen (PSA) were determined by western blotting. RNA interference of p53 was achieved by transient transfection. Reverse transcription-polymerase chain reaction was performed for mRNA expression of AR. Nuclear translocation of AR was visualized by microscopy. Apoptosis was quantified by DNA fragmentation assay or flow cytometry after Annexin V-propidium iodide staining. RESULTS HNK and its dichloroacetate analog (HDCA) were relatively more effective in suppressing cell viability and AR protein level than honokiol epoxide or biseugenol. Nuclear translocation of AR stimulated by a synthetic androgen (R1881) was markedly suppressed in the presence of HNK. Downregulation of AR protein resulting from HNK exposure was attributable to transcriptional repression as well as proteasomal degradation. HNK-mediated suppression of AR protein was maintained in LNCaP cells after knockdown of p53 protein. HNK-induced apoptosis was not affected by R1881 treatment. CONCLUSIONS The present study demonstrates, for the first time, that HNK inhibits activity of AR in prostate cancer cells regardless of the p53 status. PMID:24338950

  1. Involvement of the Androgen and Glucocorticoid Receptors in Bladder Cancer

    PubMed Central

    McBeth, Lucien; Grabnar, Maria; Selman, Steven; Hinds, Terry D.

    2015-01-01

    Bladder cancer is encountered worldwide having been associated with a host of environmental and lifestyle risk factors. The disease has a male to female prevalence of 3 : 1. This disparity has raised the possibility of the androgen receptor (AR) pathway being involved in the genesis of the disease; indeed, research has shown that AR is involved in and is likely a driver of bladder cancer. Similarly, an inflammatory response has been implicated as a major player in bladder carcinogenesis. Consistent with this concept, recent work on anti-inflammatory glucocorticoid signaling points to a pathway that may impact bladder cancer. The glucocorticoid receptor- (GR-) α isoform has an important role in suppressing inflammatory processes, which may be attenuated by AR in the development of bladder cancer. In addition, a GR isoform that is inhibitory to GRα, GRβ, is proinflammatory and has been shown to induce cancer growth. In this paper, we review the evidence of inflammatory mediators and the relationship of AR and GR isoforms as they relate to the propensity for bladder cancer. PMID:26347776

  2. The androgen receptor mediates antiapoptotic function in myometrial cells.

    PubMed

    Li, H; Li, Y; Morin, D; Plymate, S; Lye, S; Dong, X

    2014-01-01

    During pregnancy, myometrial phenotype is programmed into three characteristic stages referred to as the early proliferative, the midterm hypertrophic, and the late contractile stage. Increased myometrial growth in the early and midterm of pregnancy involves a complex process of cell proliferation, antiapoptosis and differentiation. We have previously demonstrated that the androgen receptor (AR) is required for myometrial cell proliferation by modulating IGF-1 signaling during early pregnancy. Here, we report that AR also exerts its antiapoptotic function in human myometrial cells. Enhanced AR expression protects, whereas AR silencing sensitizes myometrial cells to both intrinsic and extrinsic apoptotic stimuli. AR agonist inhibits, whereas AR antagonist induces myometrial cells to undergo apoptotic cell death. Gene microarray analysis confirms that the central functions of AR in myometrial cells are to regulate cell cycling and apoptosis through three major gene groups involving the epidermal growth factor (EGF) signaling, RNA splicing and DNA repair processes. AR mediates its antiapoptotic function through two distinct pathways. In the receptor-dependent pathway, AR is required for the expression of several protein factors within the EGF signaling pathway. Through the PI3K/Akt pathway, AR enhances the expression of the antiapoptotic protein Mcl-1. In the ligand-dependent pathway, AR agonist triggers the activation of Src kinase, which in turn phosphorylates STAT3 to increase Mcl-1 expression. We conclude from these results that the AR signaling exerts antiapoptotic function in myometrial cells, further supporting its key role in programming of myometrial phenotype. PMID:25032861

  3. Dominant-Negative Androgen Receptor Inhibition of Intracrine Androgen-Dependent Growth of Castration-Recurrent Prostate Cancer

    PubMed Central

    Kantor, Boris; Li, Xiangping; Haack, Karin; Moore, Dominic T.; Wilson, Elizabeth M.

    2012-01-01

    Background Prostate cancer (CaP) is the second leading cause of cancer death in American men. Androgen deprivation therapy is initially effective in CaP treatment, but CaP recurs despite castrate levels of circulating androgen. Continued expression of the androgen receptor (AR) and its ligands has been linked to castration-recurrent CaP growth. Principal Finding In this report, the ligand-dependent dominant-negative ARΔ142–337 (ARΔTR) was expressed in castration-recurrent CWR-R1 cell and tumor models to elucidate the role of AR signaling. Expression of ARΔTR decreased CWR-R1 tumor growth in the presence and absence of exogenous testosterone (T) and improved survival in the presence of exogenous T. There was evidence for negative selection of ARΔTR transgene in T-treated mice. Mass spectrometry revealed castration-recurrent CaP dihydrotestosterone (DHT) levels sufficient to activate AR and ARΔTR. In the absence of exogenous testosterone, CWR-R1-ARΔTR and control cells exhibited altered androgen profiles that implicated epithelial CaP cells as a source of intratumoral AR ligands. Conclusion The study provides in vivo evidence that activation of AR signaling by intratumoral AR ligands is required for castration-recurrent CaP growth and that epithelial CaP cells produce sufficient active androgens for CaP recurrence during androgen deprivation therapy. Targeting intracrine T and DHT synthesis should provide a mechanism to inhibit AR and growth of castration-recurrent CaP. PMID:22272301

  4. Crosstalk between RON and androgen receptor signaling in the development of castration resistant prostate cancer

    PubMed Central

    Batth, Izhar; Yun, Huiyoung; Hussain, Suleman; Meng, Peng; Osumulski, Powel; Huang, Tim Hui-Ming; Bedolla, Roble; Profit, Amanda; Reddick, Robert; Kumar, Addanki

    2016-01-01

    Castrate-resistant prostate cancer (CRPC) is the fatal form of prostate cancer. Although reactivation of androgen receptor (AR) occurs following androgen deprivation, the precise mechanism involved is unclear. Here we show that the receptor tyrosine kinase, RON alters mechanical properties of cells to influence epithelial to mesenchymal transition and functions as a transcription factor to differentially regulate AR signaling. RON inhibits AR activation and subset of AR-regulated transcripts in androgen responsive LNCaP cells. However in C4-2B, a castrate-resistant sub-line of LNCaP and AR-negative androgen independent DU145 cells, RON activates subset of AR-regulated transcripts. Expression of AR in PC-3 cells leads to activation of RON under androgen deprivation but not under androgen proficient conditions implicating a role for RON in androgen independence. Consistently, RON expression is significantly elevated in castrate resistant prostate tumors. Taken together our results suggest that RON activation could aid in promoting androgen independence and that inhibition of RON in combination with AR antagonist(s) merits serious consideration as a therapeutic option during hormone deprivation therapy. PMID:26872377

  5. In Silico and In Vitro Investigation of the Piperine's Male Contraceptive Effect: Docking and Molecular Dynamics Simulation Studies in Androgen-Binding Protein and Androgen Receptor.

    PubMed

    Chinta, Gopichand; Ramya Chandar Charles, Mariasoosai; Klopčič, Ivana; Sollner Dolenc, Marija; Periyasamy, Latha; Selvaraj Coumar, Mohane

    2015-07-01

    Understanding the molecular mechanism of action of traditional medicines is an important step towards developing marketable drugs from them. Piperine, an active constituent present in the Piper species, is used extensively in Ayurvedic medicines (practiced on the Indian subcontinent). Among others, piperine is known to possess a male contraceptive effect; however, the molecular mechanism of action for this effect is not very clear. In this regard, detailed docking and molecular dynamics simulation studies of piperine with the androgen-binding protein and androgen receptors were carried out. Androgen receptors control male sexual behavior and fertility, while the androgen-binding protein binds testosterone and maintains its concentration at optimal levels to stimulate spermatogenesis in the testis. It was found that piperine docks to the androgen-binding protein, similar to dihydrotestosterone, and to androgen receptors, similar to cyproterone acetate (antagonist). Also, the piperine-androgen-binding protein and piperine-androgen receptors interactions were found to be stable throughout 30 ns of molecular dynamics simulation. Further, two independent simulations for 10 ns each also confirmed the stability of these interactions. Detailed analysis of the piperine-androgen-binding protein interactions shows that piperine interacts with Ser42 of the androgen-binding protein and could block the binding with its natural ligands dihydrotestosterone/testosterone. Moreover, piperine interacts with Thr577 of the androgen receptors in a manner similar to the antagonist cyproterone acetate. Based on the in silico results, piperine was tested in the MDA-kb2 cell line using the luciferase reporter gene assay and was found to antagonize the effect of dihydrotestosterone at nanomolar concentrations. Further detailed biochemical experiments could help to develop piperine as an effective male contraceptive agent in the future. PMID:26039262

  6. RECOMBINANT ANDROGEN RECEPTOR (AR) BINDING ACROSS VERTEBRATE SPECIES: COMPARISON OF BINDING OF ENVIRONMENTAL COMPOUNDS TO HUMAN, RAINBOW TROUT AND FATHEAD MINNOW AR.

    EPA Science Inventory

    In vitro screening assays designed to identify androgen mimics or antagonists typically use mammalian (rat, human) androgen receptors (AR). Although the amino acid sequences of receptors from nonmammalian vertebrates are not identical to the mammalian receptors, it is uncertain ...

  7. Androgen receptor mutations in carcinoma of the prostate: significance for endocrine therapy.

    PubMed

    Culig, Z; Klocker, H; Bartsch, G; Hobisch, A

    2001-01-01

    Endocrine therapy for advanced prostate cancer involves androgen ablation (orchiectomy or application of luteinizing hormone releasing hormone analogs) and/or blockade of the androgen receptor (AR) with either steroidal (cyproterone acetate) or nonsteroidal (hydroxyflutamide, bicalutamide and nilutamide) antiandrogens. These antagonists prevent androgen-induced conformational change and activation of the AR. During long term androgen ablation, the AR adapts to an environment with low androgen concentrations and becomes hypersensitive to low concentrations of androgens, either alone or in combination with various cellular regulators. Bicalutamide can switch from antagonist to agonist during long-term androgen withdrawal, as shown in prostate cancer LNCaP cells. AR point mutations were detected in metastatic lesions from human prostate cancer more frequently than in primary tumors. Although functional characterization of only some mutant AR detected in prostate cancer tissue has been performed, data available suggest that they are activated by dihydrotestosterone, its precursors and metabolites, synthetic androgens, estrogenic and progestagenic steroids and hydroxyflutamide. A direct association between AR mutations and endocrine withdrawal syndrome has been investigated in only one study thus far. There is no evidence at present that activation of any of the mutant AR genes detected in prostate cancer is enhanced in the presence of a nonsteroidal AR stimulator. Coactivators of the AR are proteins that associate with the receptor, possess histone acetylase activity and facilitate AR activation. The coregulatory proteins ARA70 and ARA160 differentially affected the activity of the mutated AR Glu(231)-->Gly, which was discovered in a mouse authochthonous prostate tumor. ARA70 enhanced receptor activation by both androgen and estradiol, whereas ARA160 augmented only androgen-induced AR activity. Novel experimental therapies that down-regulate AR expression have been

  8. Androgen Receptor Roles in Insulin Resistance and Obesity in Males: The Linkage of Androgen-Deprivation Therapy to Metabolic Syndrome

    PubMed Central

    Yu, I-Chen; Lin, Hung-Yun; Sparks, Janet D.; Yeh, Shuyuan

    2014-01-01

    Prostate cancer (PCa) is one of the most frequently diagnosed malignancies in men. Androgen-deprivation therapy (ADT) is the first-line treatment and fundamental management for men with advanced PCa to suppress functions of androgen/androgen receptor (AR) signaling. ADT is effective at improving cancer symptoms and prolonging survival. However, epidemiological and clinical studies support the notion that testosterone deficiency in men leads to the development of metabolic syndrome that increases cardiovascular disease risk. The underlying mechanisms by which androgen/AR signaling regulates metabolic homeostasis in men are complex, and in this review, we discuss molecular mechanisms mediated by AR signaling that link ADT to metabolic syndrome. Results derived from various AR knockout mouse models reveal tissue-specific AR signaling that is involved in regulation of metabolism. These data suggest that steps be taken early to manage metabolic complications associated with PCa patients receiving ADT, which could be accomplished using tissue-selective modulation of AR signaling and by treatment with insulin-sensitizing agents. PMID:25249645

  9. Increased cytosolic androgen receptor binding in rat striated muscle following denervation and disuse

    NASA Technical Reports Server (NTRS)

    Bernard, P. A.; Fishman, P. S.; Max, S. R.; Rance, N. E.

    1984-01-01

    The effects of denervation and disuse on cytosolic androgen receptor binding by rat striated muscle are investigated. Denervation of the extensor digitorum longus and tibialis anterior muscles caused by a 40-50-percent increase in cytosolic androgen receptor concentration with no change in apparent binding affinity. This effect was evident at 6 h postdenervation, maximal at 24 h, and declined to 120 percent of the control level 72 h after denervation. A 40-percent increase in cytosolic androgen receptor concentration was also noted 24 hr after denervation of the hormone-sensitive levator ani muscle. The effect of denervation on androgen receptors was blocked by in vivo injection of cycloheximide; therefore, de novo receptor synthesis probably is not involved in the observed increase. Disuse, produced by subperineurial injection of tetrodotoxin into the tibial and common peroneal branches of the sciatic nerve, mimicked the effect of denervation on androgen receptor binding, suggesting that neuromuscular activity is important in regulation of receptor concentration. Possible mechanisms subserving this effect are discussed.

  10. Androgen receptor and monoamine oxidase polymorphism in wild bonobos.

    PubMed

    Garai, Cintia; Furuichi, Takeshi; Kawamoto, Yoshi; Ryu, Heungjin; Inoue-Murayama, Miho

    2014-12-01

    Androgen receptor gene (AR), monoamine oxidase A gene (MAOA) and monoamine oxidase B gene (MAOB) have been found to have associations with behavioral traits, such as aggressiveness, and disorders in humans. However, the extent to which similar genetic effects might influence the behavior of wild apes is unclear. We examined the loci AR glutamine repeat (ARQ), AR glycine repeat (ARG), MAOA intron 2 dinucleotide repeat (MAin2) and MAOB intron 2 dinucleotide repeat (MBin2) in 32 wild bonobos, Pan paniscus, and compared them with those of chimpanzees, Pan troglodytes, and humans. We found that bonobos were polymorphic on the four loci examined. Both loci MAin2 and MBin2 in bonobos showed a higher diversity than in chimpanzees. Because monoamine oxidase influences aggressiveness, the differences between the polymorphisms of MAin2 and MBin2 in bonobos and chimpanzees may be associated with the differences in aggression between the two species. In order to understand the evolution of these loci and AR, MAOA and MAOB in humans and non-human primates, it would be useful to conduct future studies focusing on the potential association between aggressiveness, and other personality traits, and polymorphisms documented in bonobos. PMID:25606465

  11. BA321, a novel carborane analog that binds to androgen and estrogen receptors, acts as a new selective androgen receptor modulator of bone in male mice.

    PubMed

    Watanabe, Kenta; Hirata, Michiko; Tominari, Tsukasa; Matsumoto, Chiho; Endo, Yasuyuki; Murphy, Gillian; Nagase, Hideaki; Inada, Masaki; Miyaura, Chisato

    2016-09-01

    Carboranes are a class of carbon-containing polyhedral boron cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors such as estrogen receptor (ER) and androgen receptor (AR). We have synthesized BA321, a novel carborane compound, which binds to AR. We found here that it also binds to ERs, ERα and ERβ. In orchidectomized (ORX) mice, femoral bone mass was markedly reduced due to androgen deficiency and BA321 restored bone loss in the male, whilst the decreased weight of seminal vesicle in ORX mice was not recovered by administration of BA321. In female mice, BA321 acts as a pure estrogen agonist, and restored both the loss of bone mass and uterine atrophy due to estrogen deficiency in ovariectomized (OVX) mice. In bone tissues, the trabecular bone loss occurred in both ORX and OVX mice, and BA321 completely restored the trabecular bone loss in both sexes. Cortical bone loss occurred in ORX mice but not in OVX mice, and BA321 clearly restored cortical bone loss due to androgen deficiency in ORX mice. Therefore, BA321 is a novel selective androgen receptor modulator (SARM) that may offer a new therapy option for osteoporosis in the male. PMID:27402268

  12. Clinical, cytogenetic and molecular analysis of androgen insensitivity syndromes from south Indian cohort and detection and in-silico characterization of androgen receptor gene mutations.

    PubMed

    V G, Abilash; S, Radha; K M, Marimuthu; K, Thangaraj; S, Arun; S, Nishu; A, Mohana Priya; J, Meena; D, Anuradha

    2016-01-30

    Rare cases of 9 complete androgen insensitivity syndromes, 9 cases of partial androgen insensitivity syndromes and equal number of male control samples were selected for this study. Few strong variations in clinical features were noticed; Giemsa banded metaphase revealed a 46,XY karyotype and the frequency of chromosome aberrations were significantly higher when compared with control samples. DNA sequence analysis of the androgen receptor gene of androgen insensitivity syndromes revealed three missense mutations - c.C1713>G resulting in the replacement of a highly conserved histidine residue with glutamine p.(His571Glu) in DNA-binding domain, c.A1715>G resulting in the replacement of a highly conserved tyrosine residue with cysteine p.(Tyr572Cys) in DNA-binding domain and c.G2599>A resulting in the replacement of a highly conserved valine residue with methionine p.(Val867Met) in ligand-binding domain of androgen receptor gene respectively. The heterozygous type of mutations c.C1713>G and c.G2599>A observed in mothers of the patients for familial cases concluding that the mutation was inherited from the mother. The novel mutation c.C1713>G is reported first time in androgen insensitivity syndrome. In-silico analysis of mutations observed in androgen receptor gene of androgen insensitivity syndrome predicted that the substitution at Y572C and V867M could probably disrupt the protein structure and function. PMID:26688387

  13. Androgen receptor transcriptionally regulates μ-opioid receptor expression in rat trigeminal ganglia.

    PubMed

    Lee, Ki Seok; Zhang, Youping; Asgar, Jamila; Auh, Q-Schick; Chung, Man-Kyo; Ro, Jin Y

    2016-09-01

    The involvement of testosterone in pain, inflammation, and analgesia has been reported, but the role of androgen receptor (AR), a steroid receptor for testosterone, is not well understood. We have previously shown that peripheral inflammation upregulates μ-opioid receptor (MOR) in rat trigeminal ganglia (TG) in a testosterone-dependent manner. In this study, we hypothesized that testosterone regulates MOR expression via transcriptional activities of AR in TG. We first examined whether AR is co-expressed with MOR in TG neurons. Our immunohistochemical experiment revealed that AR staining is detected in neurons of all sizes in TG and that a subset of AR is expressed in MOR as well as in TRPV1-positive neurons. We identified the promoter region of the rat MOR gene contains putative AR binding sites. Using chromatin immunoprecipitation assay, we demonstrated that AR directly binds to these sites in TG extracts. We confirmed with luciferase reporter assay that AR activated the MOR promoter in response to androgens in a human neuroblastoma cell line (5H-5YSY). These data demonstrated that AR functions as a transcriptional regulator of the MOR gene activity. Finally, we showed that flutamide, a specific AR antagonist, prevents complete Freund's adjuvant (CFA)-induced upregulation of MOR mRNA in TG, and that flutamide dose-dependently blocks the efficacy of DAMGO, a specific MOR agonist, on CFA-induced mechanical hypersensitivity. Our results expand the knowledge regarding the role of androgens and their receptor in pain and analgesia and have important clinical implications, particularly for inflammatory pain patients with low or compromised plasma testosterone levels. PMID:27320211

  14. Research Resource: Androgen Receptor Activity Is Regulated Through the Mobilization of Cell Surface Receptor Networks

    PubMed Central

    Hsiao, Jordy J.; Ng, Brandon H.; Smits, Melinda M.; Martinez, Harryl D.; Jasavala, Rohini J.; Hinkson, Izumi V.; Fermin, Damian; Eng, Jimmy K.; Nesvizhskii, Alexey I.

    2015-01-01

    The aberrant expression of androgen receptor (AR)-dependent transcriptional programs is a defining pathology of the development and progression of prostate cancers. Transcriptional cofactors that bind AR are critical determinants of prostate tumorigenesis. To gain a deeper understanding of the proteins linked to AR-dependent gene transcription, we performed a DNA-affinity chromatography-based proteomic screen designed to identify proteins involved in AR-mediated gene transcription in prostate tumor cells. Functional experiments validated the coregulator roles of known AR-binding proteins in AR-mediated transcription in prostate tumor cells. More importantly, novel coregulatory functions were detected in components of well-established cell surface receptor-dependent signal transduction pathways. Further experimentation demonstrated that components of the TNF, TGF-β, IL receptor, and epidermal growth factor signaling pathways modulated AR-dependent gene transcription and androgen-dependent proliferation in prostate tumor cells. Collectively, our proteomic dataset demonstrates that the cell surface receptor- and AR-dependent pathways are highly integrated, and provides a molecular framework for understanding how disparate signal-transduction pathways can influence AR-dependent transcriptional programs linked to the development and progression of human prostate cancers. PMID:26181434

  15. Identification of androgen receptors in normal human osteoblast-like cells

    SciTech Connect

    Colvard, D.S.; Eriksen, E.F.; Keeting, P.E.; Riggs, B.L.; Spelsberg, T.C. ); Wilson, E.M.; Lubahn, D.B.; French, F.S. )

    1989-02-01

    The sex steroids, androgens and estrogens, are major regulators of bone metabolism. However, whether these hormones act on bone cells through direct or indirect mechanisms has remained unclear. A nuclear binding assay recently used to demonstrate estrogen receptors in bone was used to identify specific nuclear binding of a tritiated synthetic androgen, ({sup 3}H)R1881 (methyltrienolone), in 21 of 25 (84%) human osteoblast-like cell strains and a concentration of bound steroid receptors of 821 {plus minus} 140 molecules per cell nucleus. Binding was saturable and steroid-specific. Androgen receptor gene expression in osteoblasts was confirmed by RNA blot analysis. Relative concentrations of androgen and estrogen receptors were compared by measuring specific nuclear estrogen binding. Nuclear binding of ({sup 3}H)estradiol was observed in 27 of 30 (90%) cell strains; the concentration of bound estradiol receptor was 1537 {plus minus} 221 molecules per cell nucleus. The concentrations of nuclear binding sites were similar in males and females for both ({sup 3}H)R1881 and ({sup 3}H)estradiol. The authors conclude that both androgens and estrogens act directly on human bone cells through their respective receptor-mediated mechanisms.

  16. Identification of an anabolic selective androgen receptor modulator that actively induces death of androgen-independent prostate cancer cells.

    PubMed

    Schmidt, Azriel; Meissner, Robert S; Gentile, Michael A; Chisamore, Michael J; Opas, Evan E; Scafonas, Angela; Cusick, Tara E; Gambone, Carlo; Pennypacker, Brenda; Hodor, Paul; Perkins, James J; Bai, Chang; Ferraro, Damien; Bettoun, David J; Wilkinson, Hilary A; Alves, Stephen E; Flores, Osvaldo; Ray, William J

    2014-09-01

    Prostate cancer (PCa) initially responds to inhibition of androgen receptor (AR) signaling, but inevitably progresses to hormone ablation-resistant disease. Much effort is focused on optimizing this androgen deprivation strategy by improving hormone depletion and AR antagonism. However we found that bicalutamide, a clinically used antiandrogen, actually resembles a selective AR modulator (SARM), as it partially regulates 24% of endogenously 5α-dihydrotestosterone (DHT)-responsive genes in AR(+) MDA-MB-453 breast cancer cells. These data suggested that passive blocking of all AR functions is not required for PCa therapy. Hence, we adopted an active strategy that calls for the development of novel SARMs, which induce a unique gene expression profile that is intolerable to PCa cells. Therefore, we screened 3000 SARMs for the ability to arrest the androgen-independent growth of AR(+) 22Rv1 and LNCaP PCa cells but not AR(-) PC3 or DU145 cells. We identified only one such compound; the 4-aza-steroid, MK-4541, a potent and selective SARM. MK-4541 induces caspase-3 activity and cell death in both androgen-independent, AR(+) PCa cell lines but spares AR(-) cells or AR(+) non-PCa cells. This activity correlates with its promoter context- and cell-type dependent transcriptional effects. In rats, MK-4541 inhibits the trophic effects of DHT on the prostate, but not the levator ani muscle, and triggers an anabolic response in the periosteal compartment of bone. Therefore, MK-4541 has the potential to effectively manage prostatic hypertrophic diseases owing to its antitumor SARM-like mechanism, while simultaneously maintaining the anabolic benefits of natural androgens. PMID:24565564

  17. Androgen receptor and immune inflammation in benign prostatic hyperplasia and prostate cancer

    PubMed Central

    Izumi, Kouji; Li, Lei; Chang, Chawnshang

    2014-01-01

    Both benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are frequent diseases in middle-aged to elderly men worldwide. While both diseases are linked to abnormal growth of the prostate, the epidemiological and pathological features of these two prostate diseases are different. BPH nodules typically arise from the transitional zone, and, in contrast, PCa arises from the peripheral zone. Androgen deprivation therapy alone may not be sufficient to cure these two prostatic diseases due to its undesirable side effects. The alteration of androgen receptor-mediated inflammatory signals from infiltrating immune cells and prostate stromal/epithelial cells may play key roles in those unwanted events. Herein, this review will focus on the roles of androgen/androgen receptor signals in the inflammation-induced progression of BPH and PCa. PMID:26594314

  18. Androgen receptor is overexpressed in boys with severe hypospadias, and ZEB1 regulates androgen receptor expression in human foreskin cells

    PubMed Central

    Qiao, Liang; Tasian, Gregory E.; Zhang, Haiyang; Cao, Mei; Ferretti, Max; Cunha, Gerald R.; Baskin, Laurence S.

    2012-01-01

    INTRODUCTION ZEB1 is overexpressed in patients with severe hypospadias. We examined the interaction between ZeB1 and the androgen receptor (AR) in vitro and the expression of AR in boys with hypospadias. RESULTS ZEB1 and AR colocalize to the nucleus. Estrogen upregulated ZEB1 and AR expression. Chromatin immunoprecipitation (ChIP) demonstrated that ZEB1 binds to an E-box sequence in the AR gene promoter. AR expression is higher in subjects with severe hypospadias than those with mild hypospadias and control subjects (P < 0.05). ZEB1 physically interacts with AR in human foreskin cells. DISCUSSION AR is overexpressed in patients with severe hypospadias. Environmental estrogenic compounds may increase the risk of hypospadias by facilitating the interaction between ZEB1 and AR. METHODS Hs68 cells, a fibroblast cell line derived from neonatal human foreskin, were exposed to 0, 10, and 100 nmol/l of estrogen, after which the cellular localization of ZEB1 and AR was assessed using immunocytochemistry. To determine if ZEB1 interacted with the AR gene, ChIP was performed using ZEB1 antibody and polymerase chain reaction (PCR) for AR. Second, AR expression was quantified using real-time PcR and western blot in normal subjects (n = 32), and subjects with mild (n = 16) and severe hypospadia (n = 16). PMID:22391641

  19. The neural androgen receptor: a therapeutic target for myelin repair in chronic demyelination.

    PubMed

    Hussain, Rashad; Ghoumari, Abdel M; Bielecki, Bartosz; Steibel, Jérôme; Boehm, Nelly; Liere, Philippe; Macklin, Wendy B; Kumar, Narender; Habert, René; Mhaouty-Kodja, Sakina; Tronche, François; Sitruk-Ware, Regine; Schumacher, Michael; Ghandour, M Said

    2013-01-01

    Myelin regeneration is a major therapeutic goal in demyelinating diseases, and the failure to remyelinate rapidly has profound consequences for the health of axons and for brain function. However, there is no efficient treatment for stimulating myelin repair, and current therapies are limited to anti-inflammatory agents. Males are less likely to develop multiple sclerosis than females, but often have a more severe disease course and reach disability milestones at an earlier age than females, and these observations have spurred interest in the potential protective effects of androgens. Here, we demonstrate that testosterone treatment efficiently stimulates the formation of new myelin and reverses myelin damage in chronic demyelinated brain lesions, resulting from the long-term administration of cuprizone, which is toxic for oligodendrocytes. In addition to the strong effect of testosterone on myelin repair, the number of activated astrocytes and microglial cells returned to low control levels, indicating a reduction of neuroinflammatory responses. We also identify the neural androgen receptor as a novel therapeutic target for myelin recovery. After the acute demyelination of cerebellar slices in organotypic culture, the remyelinating actions of testosterone could be mimicked by 5α-dihydrotestosterone, a metabolite that is not converted to oestrogens, and blocked by the androgen receptor antagonist flutamide. Testosterone treatment also failed to promote remyelination after chronic cuprizone-induced demyelination in mice with a non-functional androgen receptor. Importantly, testosterone did not stimulate the formation of new myelin sheaths after specific knockout of the androgen receptor in neurons and macroglial cells. Thus, the neural brain androgen receptor is required for the remyelination effect of testosterone, whereas the presence of the receptor in microglia and in peripheral tissues is not sufficient to enhance remyelination. The potent synthetic

  20. Androgen receptor co-activator Hic-5/ARA55 as a molecular regulator of androgen sensitivity in dermal papilla cells of human hair follicles.

    PubMed

    Inui, Shigeki; Fukuzato, Yoko; Nakajima, Takeshi; Kurata, Sotaro; Itami, Satoshi

    2007-10-01

    Androgen site-specifically affects human hair growth after puberty through androgen receptors in the dermal papilla, which transactivate target genes acting in conjunction with co-activators. To examine the regulation of androgen sensitivity in hair follicles, we focused on androgen receptor co-activator Hic-5/ARA55. Its interaction with transfected androgen receptor in beard dermal papilla cells was confirmed with mammalian two-hybrid assays. The semiquantitative reverse transcriptase-polymerase chain reaction showed that Hic-5/ARA55 mRNA expression was high in dermal papilla cells from the beard and bald frontal scalp but low in cells from the occipital scalp. To determine whether Hic-5/ARA55 mRNA level correlates with its endogenous activity, we studied the effect of dominant negative Hic-5/ARA55 on transfected androgen receptor transactivation induced by R1881 using mouse mammary tumor virus-luciferase assays. We found that it suppressed the transactivation by 64.5 and 71.4% in dermal papilla cells from the beard and bald frontal scalp, respectively, whereas it showed no significant effect in cells from the occipital scalp. Our findings suggest that Hic-5/ARA55 is a molecular regulator for androgen sensitivity in human hair follicles. PMID:17508020

  1. Impaired spermatogenesis is not an obligate expression of receptor-defective androgen resistance.

    PubMed

    Pinsky, L; Kaufman, M; Killinger, D W

    1989-01-01

    We are studying a man who presented at age 21 years with severe extragenital subvirilization despite high-normal to above-normal levels of plasma testosterone for at least 5 years. At puberty, his penis, scrotum, and testes matured normally, and he did not develop gynecomastia; however, his voice, muscularity, and facial, sexual, and body hair remained immature. A 2.5-ml ejaculate yielded normal results for sperm density, morphology, and motility. Because persistent undervirilization was emotionally disabling, he has received pharmacologic doses of testosterone enanthate intramuscularly for 3.5 years. The treatment has improved his virilization and masculine self-image substantially, and his semen analysis has remained well within the normal range. The androgen receptor in his genital skin fibroblasts has a distinctively mutant phenotype: it has a low affinity (increased apparent equilibrium dissociation constant, Kd) for 5 alpha-dihydrotestosterone and two synthetic androgens, mibolerone (MB) and methyltrienolone (MT), and its binding capacity (Bmax) is normal for the other two ligands, but questionably low for MT. In addition, it up-regulates its activity normally in response to prolonged incubation with androgen, and its androgen-receptor complexes are not thermolabile. Our study of this man permits two conclusions: impaired spermatogenesis is not the irreducible expression of receptor-defective androgen resistance in man; and androgen pharmacotherapy may be remedial for those in whom extragenital subvirilization is emotionally costly and subnormal spermatogenesis is not an inevitable side effect of such therapy. PMID:2705470

  2. Targeting Alternative Sites on the Androgen Receptor to Treat Castration-Resistant Prostate Cancer

    PubMed Central

    Lallous, Nada; Dalal, Kush; Cherkasov, Artem; Rennie, Paul S.

    2013-01-01

    Recurrent, metastatic prostate cancer continues to be a leading cause of cancer-death in men. The androgen receptor (AR) is a modular, ligand-inducible transcription factor that regulates the expression of genes that can drive the progression of this disease, and as a consequence, this receptor is a key therapeutic target for controlling prostate cancer. The current drugs designed to directly inhibit the AR are called anti-androgens, and all act by competing with androgens for binding to the androgen/ligand binding site. Unfortunately, with the inevitable progression of the cancer to castration resistance, many of these drugs become ineffective. However, there are numerous other regulatory sites on this protein that have not been exploited therapeutically. The regulation of AR activity involves a cascade of complex interactions with numerous chaperones, co-factors and co-regulatory proteins, leading ultimately to direct binding of AR dimers to specific DNA androgen response elements within the promoter and enhancers of androgen-regulated genes. As part of the family of nuclear receptors, the AR is organized into modular structural and functional domains with specialized roles in facilitating their inter-molecular interactions. These regions of the AR present attractive, yet largely unexploited, drug target sites for reducing or eliminating androgen signaling in prostate cancers. The design of small molecule inhibitors targeting these specific AR domains is only now being realized and is the culmination of decades of work, including crystallographic and biochemistry approaches to map the shape and accessibility of the AR surfaces and cavities. Here, we review the structure of the AR protein and describe recent advancements in inhibiting its activity with small molecules specifically designed to target areas distinct from the receptor’s androgen binding site. It is anticipated that these new classes of anti-AR drugs will provide an additional arsenal to treat

  3. Molecular analysis of the androgen receptor in ten prostate cancer specimens obtained before and after androgen ablation.

    PubMed

    Lamb, Dolores J; Puxeddu, Efisio; Malik, Nusrat; Stenoien, David L; Nigam, Rajni; Saleh, George Y; Mancini, Michael; Weigel, Nancy L; Marcelli, Marco

    2003-01-01

    Hormonal or androgen-ablation (AA) therapy is the predominant form of systemic treatment for metastatic prostate cancer. Although an initial response to AA is observed in 70%-80% of patients with advanced disease, most tumors eventually progress to androgen-independent growth, and only a minority of affected individuals are alive 5 years following initiation of treatment. Because AA induces a dramatic change in the hormonal milieu of the patient and because these tumors maintain the ability to proliferate, it is possible that this treatment selects a population of cells with mutated androgen receptors (ARs) that sustain growth despite the absence of circulating androgen. To test this hypothesis we investigated the molecular structure of the AR in 10 prostate cancer specimens obtained before and after AA. Tumors (coded A through L) were microdissected to uniquely enrich genomic DNA from cancer cells. Exons 1-8 of the AR were screened by polymerase chain reaction, single-stranded conformational polymorphism, and sequence analysis. A mutation consisting of an expansion of the polyglutamine (poly-Q) repeat from 20 (found in 100% of the sequences of specimens obtained before AA) to 26 (found in 70% of the sequences of specimens obtained after AA) was detected in patient F. The 26 glutamine (Q26) AR readily translocated to the nucleus upon addition of androgen, and did not show significant differences in its ability to bind (3)[H]-dihydrotestosterone compared to its wild-type counterpart. Nevertheless, analysis of transcriptional activity showed that the Q66 AR was transcriptionally 30%-50% less active than the wild-type molecule. Because clones of AR with an expanded poly-Q tract were detected only in the specimen from patient F obtained after AA, we conclude that in specific circumstances, AA treatments can select variant forms of the AR in the prostate of patients affected by prostate cancer. Further experiments are needed to conclusively determine whether the Q26

  4. Mechanistic relationship between androgen receptor polyglutamine tract truncation and androgen-dependent transcriptional hyperactivity in prostate cancer cells.

    PubMed

    Wang, Qianben; Udayakumar, T S; Vasaitis, Tadas S; Brodie, Angela M; Fondell, Joseph D

    2004-04-23

    Androgen receptor (AR) signaling pathways mediate critical events in normal and neoplastic prostate growth. Shortening of the polymorphic N-terminal polyglutamine (poly(Q)) tract of the AR gene leads to transcriptional hyperactivity and has been correlated with an increased risk of prostate cancer. The underlying mechanisms for these effects are poorly understood. We show here that androgen-dependent cellular proliferation and transcription in prostate cancer cells is inversely correlated to the length of the AR poly(Q) region. We further show that AR proteins containing a shortened poly(Q) region functionally respond to lower concentrations of androgens than wild type AR. Whereas DNA binding activity is relatively unaffected by AR poly(Q) variation, we found that ligand binding affinity and the ligand-induced NH(2)- to COOH-terminal intramolecular interaction is enhanced when the poly(Q) region is shortened. Importantly, we show that AR proteins containing a shortened poly(Q) region associate in vivo with higher levels of specific p160 coactivators and components of the SWI/SNF chromatin remodeling complex as compared with the wild type AR. Collectively, our findings suggest that the AR transcriptional hyperactivity associated with shortened poly(Q) length stems from altered ligand-induced conformational changes that enhance coactivator recruitment. PMID:14966121

  5. Camptothecin disrupts androgen receptor signaling and suppresses prostate cancer cell growth

    SciTech Connect

    Liu, Shicheng; Yuan, Yiming; Okumura, Yutaka; Shinkai, Norihiro; Yamauchi, Hitoshi

    2010-04-02

    The androgen receptor (AR) is the main therapeutic target for treatment of metastatic prostate cancers. The present study demonstrates that the topoisomerase I inhibitor camptothecin selectively inhibits androgen-responsive growth of prostate cancer cells. Camptothecin strikingly inhibited mutated and wild-type AR protein expression in LNCaP and PC-3/AR cells. This inhibition coincided with decreased androgen-mediated AR phosphorylation at Ser{sup 81} and reduced androgen-mediated AR transcriptional activity in a dose-dependent manner. Additionally, camptothecin disrupted the association between AR and heat shock protein 90 and impeded binding of the synthetic androgen [{sup 3}H]R1881 to AR in LNCaP cells. Camptothecin also blocked androgen-induced AR nuclear translocation, leading to downregulation of the AR target gene PSA. In addition to decreasing the intracellular and secreted prostate-specific antigen (PSA) levels, camptothecin markedly inhibited androgen-stimulated PSA promoter activity. Collectively, our data reveal that camptothecin not only serves as a traditional genotoxic agent but, by virtue of its ability to target and disrupt AR, may also be a novel candidate for the treatment of prostate cancer.

  6. Molecular processes leading to aberrant androgen receptor signaling and castration resistance in prostate cancer

    PubMed Central

    Hu, Rong; Denmeade, Samuel R; Luo, Jun

    2011-01-01

    Hormone therapies targeting androgen receptor signaling are the mainstay of treatment for patients with advanced prostate cancer. The length of clinical remission induced by hormone therapies varies substantially among treated patients. Why some patients progress rapidly after treatment while others benefit with prolonged remission is a question that remains unsolved. The androgen receptor signaling pathway is the key molecular determinant of castration resistance, and a key target for prostate cancer drug design. Recent advances in characterizing molecular processes leading to the development of castration-resistant prostate cancer, including the discovery of multiple androgen receptor splicing variants, offer opportunities for rational development of new clinical tools or approaches to predict, monitor or control/prevent prostate cancer progression in the castrate setting. PMID:21318111

  7. GATA2 facilitates steroid receptor coactivator recruitment to the androgen receptor complex

    PubMed Central

    He, Bin; Lanz, Rainer B.; Fiskus, Warren; Geng, Chuandong; Yi, Ping; Hartig, Sean M.; Rajapakshe, Kimal; Shou, John; Wei, Liping; Shah, Shrijal S.; Foley, Christopher; Chew, Sue Anne; Eedunuri, Vijay K.; Bedoya, Diego J.; Feng, Qin; Minami, Takashi; Mitsiades, Constantine S.; Frolov, Anna; Weigel, Nancy L.; Hilsenbeck, Susan G.; Rosen, Daniel G.; Palzkill, Timothy; Ittmann, Michael M.; Song, Yongcheng; Coarfa, Cristian; O’Malley, Bert W.; Mitsiades, Nicholas

    2014-01-01

    The androgen receptor (AR) is a key driver of prostate cancer (PC), even in the state of castration-resistant PC (CRPC) and frequently even after treatment with second-line hormonal therapies such as abiraterone and enzalutamide. The persistence of AR activity via both ligand-dependent and ligand-independent mechanisms (including constitutively active AR splice variants) highlights the unmet need for alternative approaches to block AR signaling in CRPC. We investigated the transcription factor GATA-binding protein 2 (GATA2) as a regulator of AR signaling and an actionable therapeutic target in PC. We demonstrate that GATA2 directly promotes expression of both full-length and splice-variant AR, resulting in a strong positive correlation between GATA2 and AR expression in both PC cell lines and patient specimens. Conversely, GATA2 expression is repressed by androgen and AR, suggesting a negative feedback regulatory loop that, upon androgen deprivation, derepresses GATA2 to contribute to AR overexpression in CRPC. Simultaneously, GATA2 is necessary for optimal transcriptional activity of both full-length and splice-variant AR. GATA2 colocalizes with AR and Forkhead box protein A1 on chromatin to enhance recruitment of steroid receptor coactivators and formation of the transcriptional holocomplex. In agreement with these important functions, high GATA2 expression and transcriptional activity predicted worse clinical outcome in PC patients. A GATA2 small molecule inhibitor suppressed the expression and transcriptional function of both full-length and splice-variant AR and exerted potent anticancer activity against PC cell lines. We propose pharmacological inhibition of GATA2 as a first-in-field approach to target AR expression and function and improve outcomes in CRPC. PMID:25489091

  8. A New Trick of an Old Molecule: Androgen Receptor Splice Variants Taking the Stage?!

    PubMed Central

    Guo, Zhiyong; Qiu, Yun

    2011-01-01

    Prostate cancer is the second leading cause of cancer-related death in American men. Although most prostate cancers are initially androgen-dependent and respond to androgen ablation therapy, majority of them eventually relapse and progress into incurable castration-resistant (or hormone refractory) prostate cancer. The underlying mechanisms are the focus of intensive investigation for development of more effective treatment. Mounting evidence from both clinical and basic research has demonstrated that the activity of the androgen receptor (AR) is still required for castration-resistant prostate cancer. Multiple mechanisms by which AR is re-activated under androgen-depleted conditions may be involved in the development of castration resistance. The recent identification of AR splicing variants may add another layer of complexity in AR biology. The present review summarizes recent progress in study of AR splicing variants in prostate cancer. PMID:21750650

  9. Accessory Scrotum With Perineal Lipoma: Pathologic Evaluation Including Androgen Receptor Expression

    PubMed Central

    Iida, Keitaro; Mizuno, Kentaro; Nishio, Hidenori; Moritoki, Yoshinobu; Kamisawa, Hideyuki; Kurokawa, Satoshi; Kohri, Kenjiro; Hayashi, Yutaro

    2014-01-01

    Accessory scrotum is an unusual developmental anomaly defined as additional scrotal tissue in addition to a normally developed scrotum. The accessory scrotum arises posterior to the normally located scrotum and does not contain a testis. We report a case of an 18-month-old boy with an accessory scrotum attached to a perineal lipoma. We resected both and determined histologically that they were of the same tissue as the scrotum, including the presence of androgen receptor expression. To the best of our knowledge, this is the first case to assess androgen receptor expression in an accessory scrotum using immunostaining. PMID:26958486

  10. High abundance androgen receptor in goldfish brain: characteristics and seasonal changes

    SciTech Connect

    Pasmanik, M.; Callard, G.V.

    1988-08-01

    Testosterone (T) exerts its actions in brain directly via androgen receptors or, after aromatization to estradiol, via estrogen receptors. Brain aromatase activity in teleost fish is 100-1000 times greater than in mammals and would be expected to significantly reduce the quantity of androgen available for receptor binding. Experiments were carried out on the goldfish Carassius auratus to determine if androgen receptors are present in teleost brain and whether their physicochemical properties reflect elevated aromatase. Cytosolic and nuclear extracts were assayed with the use of (/sup 3/H)T and charcoal, Sephadex LH-20, or DNA-cellulose chromatography to separate bound and free steroids. Binding activity was saturable and had an equally high affinity for T and 5 alpha-dihydrotestosterone. Although mibolerone was a relatively weak competitor, the putative teleost androgen 11-ketotestosterone, methyltrienolone (R1881), estradiol, progesterone, and cortisol were poor ligands. Characteristics that distinguish this receptor from a steroid-binding protein in goldfish serum are the presence of binding activity in both nuclear and cytosolic extracts, a low rate of ligand-receptor dissociation, electrophoretic mobility, sedimentation properties in low vs. high salt, and tissue distribution. DNA cellulose-adhering and nonadhering forms were detected, but these did not differ in other variables measured. Although goldfish androgen receptors resembled those of mammals in all important physicochemical characteristics, they were unusually abundant compared to levels in rat brain, but comparable to levels in prostate and other male sex hormone target organs. Moreover, there were seasonal variations in total receptors, with a peak at spawning (April) 4- to 5-fold higher than values in reproductively inactive fish.

  11. Drug Insight: testosterone and selective androgen receptor modulators as anabolic therapies for chronic illness and aging

    PubMed Central

    Bhasin, Shalender; Calof, Olga M; Storer, Thomas W; Lee, Martin L; Mazer, Norman A; Jasuja, Ravi; Montori, Victor M; Gao, Wenqing; Dalton, James T

    2007-01-01

    SUMMARY Several regulatory concerns have hindered development of androgens as anabolic therapies, despite unequivocal evidence that testosterone supplementation increases muscle mass and strength in men; it induces hypertrophy of type I and II muscle fibers, and increases myonuclear and satellite cell number. Androgens promote differentiation of mesenchymal multipotent cells into the myogenic lineage and inhibit their adipogenic differentiation, by facilitating association of androgen receptors with β-catenin and activating T-cell factor 4. Meta-analyses indicate that testosterone supplementation increases fat-free mass and muscle strength in HIV-positive men with weight loss, glucocorticoid-treated men, and older men with low or low-normal testosterone levels. The effects of testosterone on physical function and outcomes important to patients have not, however, been studied. In older men, increased hematocrit and increased risk of prostate biopsy and detection of prostate events are the most frequent, testosterone-related adverse events. Concerns about long-term risks have restrained enthusiasm for testosterone use as anabolic therapy. Selective androgen-receptor modulators that are preferentially anabolic and that spare the prostate hold promise as anabolic therapies. We need more studies to determine whether testosterone or selective androgen-receptor modulators can induce meaningful improvements in physical function and patient-important outcomes in patients with physical dysfunction associated with chronic illness or aging. PMID:16932274

  12. Cross-species sensitivity to a novel androgen receptor agonist of potential environmental concern, spironolactone.

    PubMed

    LaLone, Carlie A; Villeneuve, Daniel L; Cavallin, Jenna E; Kahl, Michael D; Durhan, Elizabeth J; Makynen, Elizabeth A; Jensen, Kathleen M; Stevens, Kyle E; Severson, Megan N; Blanksma, Chad A; Flynn, Kevin M; Hartig, Philip C; Woodard, Jonne S; Berninger, Jason P; Norberg-King, Teresa J; Johnson, Rodney D; Ankley, Gerald T

    2013-11-01

    Spironolactone is a pharmaceutical that in humans is used to treat conditions like hirsutism, various dermatologic afflictions, and female-pattern hair loss through antagonism of the androgen receptor. Although not routinely monitored in the environment, spironolactone has been detected downstream of a pharmaceutical manufacturer, indicating a potential for exposure of aquatic species. Furthermore, spironolactone has been reported to cause masculinization of female western mosquitofish, a response indicative of androgen receptor activation. Predictive methods to identify homologous proteins to the human and western mosquitofish androgen receptor suggest that vertebrates would be more susceptible to adverse effects mediated by chemicals like spironolactone that target the androgen receptor compared with invertebrate species that lack a relevant homolog. In addition, an adverse outcome pathway previously developed for activation of the androgen receptor suggests that androgen mimics can lead to reproductive toxicity in fish. To assess this, 21-d reproduction studies were conducted with 2 fish species, fathead minnow and Japanese medaka, and the invertebrate Daphnia magna. Spironolactone significantly reduced the fecundity of medaka and fathead minnows at 50 μg/L, whereas daphnia reproduction was not affected by concentrations as large as 500 μg/L. Phenotypic masculinization of females of both fish species was observed at 5 μg/L as evidenced by formation of tubercles in fathead minnows and papillary processes in Japanese medaka. Effects in fish occurred at concentrations below those reported in the environment. These results demonstrate how a priori knowledge of an adverse outcome pathway and the conservation of a key molecular target across vertebrates can be utilized to identify potential chemicals of concern in terms of monitoring and highlight potentially sensitive species and endpoints for testing. PMID:23881739

  13. Androgen action.

    PubMed

    Werner, Ralf; Holterhus, Paul-Martin

    2014-01-01

    Androgens are important for male sex development and physiology. Their actions are mediated by the androgen receptor (AR), a ligand-dependent nuclear transcription factor. The activity of the AR is controlled at multiple stages due to ligand binding and induced structural changes assisted by the foldosome, compartmentalization, recruitment of coregulators, posttranslational modifications and chromatin remodeling, leading to subsequent transcription of androgen-responsive target genes. Beside these short-term androgen actions, there is phenomenological and experimental evidence of long-term androgen programming in mammals and in the human during sensitive programming time windows, both pre- and postnatally. At the molecular level, research into androgen insensitivity syndrome has unmasked androgen programming at the transcriptome level, in genital fibroblasts and peripheral blood mononuclear cells, and at the epigenome level. Androgens are crucial for male sex development and physiology during embryogenesis, at puberty and in adult life. Testosterone and its more potent metabolite, dihydrotestosterone, which is converted from testosterone within the target cell by 5α-reductase II, are the main androgens involved in male sex differentiation. Androgen action is mediated by a single AR. The AR belongs to the nuclear receptor 3 group C, composed of the glucocorticoid receptor (NR3C1), mineralocorticoid receptor (NR3C2), progesterone receptor (NR3C3) and AR (NR3C4), and acts as a ligand-dependent transcription factor. PMID:25247642

  14. Epidermal growth factor receptor-dependent stimulation of amphiregulin expression in androgen-stimulated human prostate cancer cells.

    PubMed Central

    Sehgal, I; Bailey, J; Hitzemann, K; Pittelkow, M R; Maihle, N J

    1994-01-01

    Amphiregulin is a heparin-binding epidermal growth factor (EGF)-related peptide that binds to the EGF receptor (EGF-R) with high affinity. In this study, we report a role for amphiregulin in androgen-stimulated regulation of prostate cancer cell growth. Androgen is known to enhance EGF-R expression in the androgen-sensitive LNCaP human prostate carcinoma cell line, and it has been suggested that androgenic stimuli may regulate proliferation, in part, through autocrine mechanisms involving the EGF-R. In this study, we demonstrate that LNCaP cells express amphiregulin mRNA and peptide and that this expression is elevated by androgenic stimulation. We also show that ligand-dependent EGF-R stimulation induces amphiregulin expression and that androgenic effects on amphiregulin synthesis are mediated through this EGF-R pathway. Parallel studies using the estrogen-responsive breast carcinoma cell line, MCF-7, suggest that regulation of amphiregulin by estrogen may also be mediated via an EGF-R pathway. In addition, heparin treatment of LNCaP cells inhibits androgen-stimulated cell growth further suggesting that amphiregulin can mediate androgen-stimulated LNCaP proliferation. Together, these results implicate an androgen-regulated autocrine loop composed of amphiregulin and its receptor in prostate cancer cell growth and suggest that the mechanism of steroid hormone regulation of amphiregulin synthesis may occur through androgen upregulation of the EGF-R and subsequent receptor-dependent pathways. Images PMID:8049525

  15. Early vertebrate chromosome duplications and the evolution of the neuropeptide Y receptor gene regions

    PubMed Central

    2008-01-01

    Background One of the many gene families that expanded in early vertebrate evolution is the neuropeptide (NPY) receptor family of G-protein coupled receptors. Earlier work by our lab suggested that several of the NPY receptor genes found in extant vertebrates resulted from two genome duplications before the origin of jawed vertebrates (gnathostomes) and one additional genome duplication in the actinopterygian lineage, based on their location on chromosomes sharing several gene families. In this study we have investigated, in five vertebrate genomes, 45 gene families with members close to the NPY receptor genes in the compact genomes of the teleost fishes Tetraodon nigroviridis and Takifugu rubripes. These correspond to Homo sapiens chromosomes 4, 5, 8 and 10. Results Chromosome regions with conserved synteny were identified and confirmed by phylogenetic analyses in H. sapiens, M. musculus, D. rerio, T. rubripes and T. nigroviridis. 26 gene families, including the NPY receptor genes, (plus 3 described recently by other labs) showed a tree topology consistent with duplications in early vertebrate evolution and in the actinopterygian lineage, thereby supporting expansion through block duplications. Eight gene families had complications that precluded analysis (such as short sequence length or variable number of repeated domains) and another eight families did not support block duplications (because the paralogs in these families seem to have originated in another time window than the proposed genome duplication events). RT-PCR carried out with several tissues in T. rubripes revealed that all five NPY receptors were expressed in the brain and subtypes Y2, Y4 and Y8 were also expressed in peripheral organs. Conclusion We conclude that the phylogenetic analyses and chromosomal locations of these gene families support duplications of large blocks of genes or even entire chromosomes. Thus, these results are consistent with two early vertebrate tetraploidizations forming a

  16. Demonstration of the Coexistence of Duplicated LH Receptors in Teleosts, and Their Origin in Ancestral Actinopterygians

    PubMed Central

    Maugars, Gersende; Dufour, Sylvie

    2015-01-01

    Pituitary gonadotropins, FSH and LH, control gonad activity in vertebrates, via binding to their respective receptors, FSHR and LHR, members of GPCR superfamily. Until recently, it was accepted that gnathostomes possess a single FSHR and a single LHR, encoded by fshr and lhcgr genes. We reinvestigated this question, focusing on vertebrate species of key-phylogenetical positions. Genome analyses supported the presence of a single fshr and a single lhcgr in chondrichthyans, and in sarcopterygians including mammals, birds, amphibians and coelacanth. In contrast, we identified a single fshr but two lhgcr in basal teleosts, the eels. We further showed the coexistence of duplicated lhgcr in other actinopterygians, including a non-teleost, the gar, and other teleosts, e.g. Mexican tetra, platyfish, or tilapia. Phylogeny and synteny analyses supported the existence in actinopterygians of two lhgcr paralogs (lhgcr1/ lhgcr2), which do not result from the teleost-specific whole-genome duplication (3R), but likely from a local gene duplication that occurred early in the actinopterygian lineage. Due to gene losses, there was no impact of 3R on the number of gonadotropin receptors in extant teleosts. Additional gene losses during teleost radiation, led to a single lhgcr (lhgcr1 or lhgcr2) in some species, e.g. medaka and zebrafish. Sequence comparison highlighted divergences in the extracellular and intracellular domains of the duplicated lhgcr, suggesting differential properties such as ligand binding and activation mechanisms. Comparison of tissue distribution in the European eel, revealed that fshr and both lhgcr transcripts are expressed in the ovary and testis, but are differentially expressed in non-gonadal tissues such as brain or eye. Differences in structure-activity relationships and tissue expression may have contributed as selective drives in the conservation of the duplicated lhgcr. This study revises the evolutionary scenario and nomenclature of gonadotropin

  17. Steroid-induced androgen receptor–oestradiol receptor β–Src complex triggers prostate cancer cell proliferation

    PubMed Central

    Migliaccio, Antimo; Castoria, Gabriella; Di Domenico, Marina; de Falco, Antonietta; Bilancio, Antonio; Lombardi, Maria; Barone, Maria Vittoria; Ametrano, Donatella; Zannini, Maria Stella; Abbondanza, Ciro; Auricchio, Ferdinando

    2000-01-01

    Treatment of human prostate carcinoma-derived LNCaP cells with androgen or oestradiol triggers simultaneous association of androgen receptor and oestradiol receptor β with Src, activates the Src/Raf-1/Erk-2 pathway and stimulates cell proliferation. Surprisingly, either androgen or oestradiol action on each of these steps is inhibited by both anti-androgens and anti-oestrogens. Similar findings for oestradiol receptor α were observed in MCF-7 or T47D cells stimulated by either oestradiol or androgens. Microinjection of LNCaP, MCF-7 and T47D cells with SrcK– abolishes steroid-stimulated S-phase entry. Data from transfected Cos cells confirm and extend the findings from these cells. Hormone-stimulated Src interaction with the androgen receptor and oestradiol receptor α or β is detected using glutathione S-transferase fusion constructs. Src SH2 interacts with phosphotyrosine 537 of oestradiol receptor α and the Src SH3 domain with a proline-rich stretch of the androgen receptor. The role of this phosphotyrosine is stressed by its requirement for association of oestradiol receptor α with Src and consequent activation of Src in intact Cos cells. PMID:11032808

  18. Beyond aggression: Androgen-receptor blockade modulates social interaction in wild meerkats.

    PubMed

    delBarco-Trillo, Javier; Greene, Lydia K; Goncalves, Ines Braga; Fenkes, Miriam; Wisse, Jillian H; Drewe, Julian A; Manser, Marta B; Clutton-Brock, Tim; Drea, Christine M

    2016-02-01

    In male vertebrates, androgens are inextricably linked to reproduction, social dominance, and aggression, often at the cost of paternal investment or prosociality. Testosterone is invoked to explain rank-related reproductive differences, but its role within a status class, particularly among subordinates, is underappreciated. Recent evidence, especially for monogamous and cooperatively breeding species, suggests broader androgenic mediation of adult social interaction. We explored the actions of androgens in subordinate, male members of a cooperatively breeding species, the meerkat (Suricata suricatta). Although male meerkats show no rank-related testosterone differences, subordinate helpers rarely reproduce. We blocked androgen receptors, in the field, by treating subordinate males with the antiandrogen, flutamide. We monitored androgen concentrations (via baseline serum and time-sequential fecal sampling) and recorded behavior within their groups (via focal observation). Relative to controls, flutamide-treated animals initiated less and received more high-intensity aggression (biting, threatening, feeding competition), engaged in more prosocial behavior (social sniffing, grooming, huddling), and less frequently initiated play or assumed a 'dominant' role during play, revealing significant androgenic effects across a broad range of social behavior. By contrast, guarding or vigilance and measures of olfactory and vocal communication in subordinate males appeared unaffected by flutamide treatment. Thus, androgens in male meerkat helpers are aligned with the traditional trade-off between promoting reproductive and aggressive behavior at a cost to affiliation. Our findings, based on rare endocrine manipulation in wild mammals, show a more pervasive role for androgens in adult social behavior than is often recognized, with possible relevance for understanding tradeoffs in cooperative systems. PMID:26545817

  19. Stilbenes inhibit androgen receptor expression in 22Rv1 castrate-resistant prostate cancer cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Androgen receptor (AR) signaling plays an important role in the development and progression of prostate cancer (PCa). Importantly, AR continues to be expressed in advanced stages of castrate-resistant PCa (CRPC), where it can have ligand- independent activity. Identification of naturally occurring s...

  20. AOP description: Androgen receptor agonism leading to reproductive dysfunction (in fish)

    EPA Science Inventory

    This adverse outcome pathway details the linkage between binding and activation of androgen receptor as a nuclear transcription factor in females and the adverse effect of reduced cumulative fecundity in repeat-spawning fish species. Cumulative fecundity is the most apical endpoi...

  1. [Epigenetic Regulation by Androgen Receptor and Possible Function in Bone Metabolism].

    PubMed

    Imai, Yuuki

    2016-07-01

    Epigenetic regulation underlying AR(Androgen receptor)mediated transcription is important component to understand pathophysiology of osteoporosis in men. In this commentary, it is reported recent findings related to epigenetic landscape governed by AR and its cofactors including lysine-specific demethylase 1 (LSD1), and possible implication for bone metabolism. PMID:27346313

  2. Species comparisons in molecular and functional attributes of the androgen and estrogen receptor

    EPA Science Inventory

    While endocrine disrupting compounds (EDCs) have the potential to act via several mechanisms of action, one of the most widely studied is the ability of environmental chemicals to interact directly with either the estrogen (ER) or androgen receptor (AR). In vitro screening assay...

  3. A Time-course Study with the Androgen Receptor Antagonist Flutamide in Fish

    EPA Science Inventory

    Flutamide, a drug registered to treat some types of prostate cancer in humans, has been used for many years as a model androgen receptor (AR) antagonist in studies aimed at characterizing disruption of the vertebrate hypothalamic-pituitary-gonadal (HPG) axis. Various studies hav...

  4. Cross species sensitivity to a novel androgen receptor agonist of potential environmental concern, spironolactone

    EPA Science Inventory

    Spironolactone (SPL) is a pharmaceutical that is used in humans as an androgen receptor (AR) antagonist to treat conditions like hirsutism, various dermatologic afflictions, and female pattern hair loss, in addition to its common usage as a diuretic to treat hypertension. Althoug...

  5. Recent Duplication and Functional Divergence in Parasitic Nematode Levamisole-Sensitive Acetylcholine Receptors

    PubMed Central

    Duguet, Thomas B.; Charvet, Claude L.; Forrester, Sean G.; Wever, Claudia M.; Dent, Joseph A.; Neveu, Cedric; Beech, Robin N.

    2016-01-01

    Helminth parasites rely on fast-synaptic transmission in their neuromusculature to experience the outside world and respond to it. Acetylcholine plays a pivotal role in this and its receptors are targeted by a wide variety of both natural and synthetic compounds used in human health and for the control of parasitic disease. The model, Caenorhabditis elegans is characterized by a large number of acetylcholine receptor subunit genes, a feature shared across the nematodes. This dynamic family is characterized by both gene duplication and loss between species. The pentameric levamisole-sensitive acetylcholine receptor has been characterized from C. elegans, comprised of five different subunits. More recently, cognate receptors have been reconstituted from multiple parasitic nematodes that are found to vary in subunit composition. In order to understand the implications of receptor composition change and the origins of potentially novel drug targets, we investigated a specific example of subunit duplication based on analysis of genome data for 25 species from the 50 helminth genome initiative. We found multiple independent duplications of the unc-29, acetylcholine receptor subunit, where codon substitution rate analysis identified positive, directional selection acting on amino acid positions associated with subunit assembly. Characterization of four gene copies from a model parasitic nematode, Haemonchus contortus, demonstrated that each copy has acquired unique functional characteristics based on phenotype rescue of transgenic C. elegans and electrophysiology of receptors reconstituted in Xenopus oocytes. We found evidence that a specific incompatibility has evolved for two subunits co-expressed in muscle. We demonstrated that functional divergence of acetylcholine receptors, driven by directional selection, can occur more rapidly than previously thought and may be mediated by alteration of receptor assembly. This phenomenon is common among the clade V parasitic

  6. Recent Duplication and Functional Divergence in Parasitic Nematode Levamisole-Sensitive Acetylcholine Receptors.

    PubMed

    Duguet, Thomas B; Charvet, Claude L; Forrester, Sean G; Wever, Claudia M; Dent, Joseph A; Neveu, Cedric; Beech, Robin N

    2016-07-01

    Helminth parasites rely on fast-synaptic transmission in their neuromusculature to experience the outside world and respond to it. Acetylcholine plays a pivotal role in this and its receptors are targeted by a wide variety of both natural and synthetic compounds used in human health and for the control of parasitic disease. The model, Caenorhabditis elegans is characterized by a large number of acetylcholine receptor subunit genes, a feature shared across the nematodes. This dynamic family is characterized by both gene duplication and loss between species. The pentameric levamisole-sensitive acetylcholine receptor has been characterized from C. elegans, comprised of five different subunits. More recently, cognate receptors have been reconstituted from multiple parasitic nematodes that are found to vary in subunit composition. In order to understand the implications of receptor composition change and the origins of potentially novel drug targets, we investigated a specific example of subunit duplication based on analysis of genome data for 25 species from the 50 helminth genome initiative. We found multiple independent duplications of the unc-29, acetylcholine receptor subunit, where codon substitution rate analysis identified positive, directional selection acting on amino acid positions associated with subunit assembly. Characterization of four gene copies from a model parasitic nematode, Haemonchus contortus, demonstrated that each copy has acquired unique functional characteristics based on phenotype rescue of transgenic C. elegans and electrophysiology of receptors reconstituted in Xenopus oocytes. We found evidence that a specific incompatibility has evolved for two subunits co-expressed in muscle. We demonstrated that functional divergence of acetylcholine receptors, driven by directional selection, can occur more rapidly than previously thought and may be mediated by alteration of receptor assembly. This phenomenon is common among the clade V parasitic

  7. Testosterone and Androgen Receptor Sensitivity in Relation to Hyperactivity Symptoms in Boys with Autism Spectrum Disorders

    PubMed Central

    2016-01-01

    Introduction Autism spectrum disorders (ASD) and hyperactivity symptoms exhibit an incidence that is male-biased. Thus androgen activity can be considered a plausible biological risk factor for these disorders. However, there is insufficient information about the association between increased androgen activity and hyperactivity symptoms in children with ASD. Methods In the present study, the relationship between parameters of androgenicity (plasmatic testosterone levels and androgen receptor sensitivity) and hyperactivity in 60 boys (age 3–15) with ASD is investigated. Given well documented differences in parent and trained examiners ratings of symptom severity, we employed a standardized parent`s questionnaire (Nisonger Child Behavior Rating Form) as well as a direct examiner`s rating (Autism diagnostic observation schedule) for assessment of hyperactivity symptoms. Results Although it was found there was no significant association between actual plasmatic testosterone levels and hyperactivity symptoms, the number of CAG triplets was significantly negatively correlated with hyperactivity symptoms (R2 = 0.118, p = 0.007) in the sample, indicating increased androgen receptor sensitivity in association with hyperactivity symptoms. Direct trained examiner´s assessment appeared to be a relevant method for evaluating of behavioral problems in the investigation of biological underpinnings of these problems in our study. Conclusions A potential ASD subtype characterized by increased rates of hyperactivity symptoms might have distinct etiopathogenesis and require a specific behavioral and pharmacological approach. We propose an increase of androgen receptor sensitivity as a biomarker for a specific ASD subtype accompanied with hyperactivity symptoms. Findings are discussed in terms of their implications for practice and future research. PMID:26910733

  8. Androgen receptors beyond prostate cancer: an old marker as a new target

    PubMed Central

    Kurzrock, Razelle

    2015-01-01

    Androgen receptors (ARs) play a critical role in the development of prostate cancer. Targeting ARs results in important salutary effects in this malignancy. Despite mounting evidence that ARs also participate in the pathogenesis and/or progression of diverse tumors, exploring the impact of hormonal manipulation of these receptors has not been widely pursued beyond prostate cancer. This review describes patterns of AR expression in a spectrum of cancers, and the potential to exploit this knowledge in the clinical therapeutic setting. PMID:25595907

  9. Selectivity in progesterone and androgen receptor binding of progestagens used in oral contraceptives

    SciTech Connect

    Kloosterboer, H.J.; Vonk-Noordegraaf, C.A.; Turpijn, E.W.

    1988-09-01

    The relative binding affinities (RBAs) of four progestational compounds (norethisterone, levonorgestrel, 3-keto-desogestrel and gestodene) for the human progesterone and androgen receptors were measured in MCF-7 cytosol and intact MCF-7 cells. For the binding to the progesterone receptor, both Org 2058 and Org 3236 (or 3-keto-desogestrel) were used as labelled ligands. The following ranking (low to high) for the RBA of the nuclear (intact cells) progesterone receptor irrespective of the ligand used is found: norethisterone much less than levonorgestrel less than 3-keto-destogestrel less than gestodene. The difference between the various progestagens is significant with the exception of that between 3-keto-desogestrel and gestodene, when Org 2058 is used as ligand. For the cytosolic progesterone receptor, the same order is found with the exception that similar RBAs are found for gestodene and 3-keto-desogestrel. The four progestagens clearly differ with respect to binding to the androgen receptor using dihydrotestosterone as labelled ligand in intact cells; the ranking (low to high) is: norethisterone less than 3 keto-desogestrel less than levonorgestrel and gestodene. The difference between 3-keto-desogestrel and levonorgestrel or gestodene is significant. The selectivity indices (ratio of the mean RBA for the progesterone receptor to that of androgen receptor) in intact cells are significantly higher for 3-keto-desogestrel and gestodene than for levonorgestrel and norethisterone. From these results we conclude that the introduction of the 18-methyl in norethisterone (levonorgestel) increases both the binding to the progesterone and androgen receptors.

  10. Androgen receptor blockade using flutamide skewed sex ratio of litters in mice.

    PubMed

    Gharagozlou, Faramarz; Youssefi, Reza; Vojgani, Mehdi; Akbarinejad, Vahid; Rafiee, Ghazaleh

    2016-01-01

    Maternal testosterone has been indicated to affect sex ratio of offspring. The present study was conducted to elucidate the role of androgen receptor in this regard by blockade of androgen receptor using flutamide in female mice. Mice were randomly assigned to two experimental groups. Mice in the control (n = 20) and treatment (n = 20) groups received 8 IU equine chorionic gonadotropin (eCG) followed by human chorionic gonadotropin (hCG) injection (8 IU) 47 hr later. In addition, mice in the control and treatment groups received four injections of ethanol-saline vehicle and flutamide solution (2.50 mg), respectively, started from 1 hr before eCG injection until hCG injection at 12-hr intervals. Conception rate was not different between the treatment (18/20: 90.00%) and control (19/20: 95.00%) groups (p > 0.05). Litter size was higher in the treatment (8.22 ± 0.26) than control (7.21 ± 0.28) group (p < 0.05). Male sex ratio was lower in the flutamide-treated mice (67/148: 45.30%) as compared with the untreated ones (80/137: 58.40%; odds ratio = 1.69; p < 0.05). In conclusion, the results showed that androgen receptor blockade could skew sex ratio of offspring toward females implying that the effect of testosterone on sex ratio might be through binding to androgen receptor. In addition, the blockade of androgen receptor using flutamide appeared to enhance litter size. PMID:27482363

  11. Distribution of androgen receptor in microdissected brain areas of the female baboon (Papio cynocephalus).

    PubMed

    Handa, R J; Roselli, C E; Resko, J A

    1988-03-29

    We measured androgen receptors in the brain and pituitary of 4 female baboons (Papio cynocephalus) by the in vitro binding of methyltrienolone (R1881) to cytosols from 17 brain subregions as well as anterior and posterior pituitaries. High levels of AR were detected in anterior (22.1 +/- 7.1 (S.E.M.) fmol/mg protein) and posterior pituitary (12.6 +/- 3.3 fmol/mg protein). In brain tissue, the highest androgen receptor levels were found in the infundibular nucleus/median eminence (9.4 +/- 2.3 fmol/mg protein), ventromedial nucleus (6.3 +/- 1.7 fmol/mg protein) and periventricular area (4.9 +/- 1.3 fmol/mg protein). Saturation analysis of anterior pituitary and brain tissue (pool of hypothalamic, preoptic area, amygdala and septum remaining after microdissection of brain nuclei) showed that [3H]R1881 binds to the androgen receptor with high specificity and affinity (Kd = 1.25 x 10(-10) M, 0.45 x 10(-10) M, in anterior pituitary and HPA cytosol, respectively). Serum testosterone levels were low in all animals (0.59 +/- 0.26 ng/ml). With these data we described the quantitative distribution of androgen receptor in the pituitary and in specific brain nuclei in a species of nonhuman primate. The distribution is similar in many respects to that described in the male rat and the data suggest a conservation of androgen receptor distribution across species. PMID:3259151

  12. Androgen receptors and experimental bone loss - an in vivo and in vitro study.

    PubMed

    Steffens, Joao Paulo; Coimbra, Leila Santana; Rossa, Carlos; Kantarci, Alpdogan; Van Dyke, Thomas E; Spolidorio, Luis Carlos

    2015-12-01

    Testosterone is a sex hormone that exhibits many functions beyond reproduction; one such function is the regulation of bone metabolism. The role played by androgen receptors during testosterone-mediated biological processes associated with bone metabolism is largely unknown. This study aims to use a periodontal disease model in vivo in order to assess the involvement of androgen receptors on microbial-induced inflammation and alveolar bone resorption in experimental bone loss. The impact of hormone deprivation was tested through both orchiectomy and chemical blockage of androgen receptor using flutamide (FLU). Additionally, the direct effect of exogenous testosterone, and the role of the androgen receptor, on osteoclastogenesis were investigated. Thirty male adult rats (n=10/group) were subjected to: 1-orchiectomy (OCX); 2-OCX sham surgery; or 3-OCX sham surgery plus FLU, four weeks before the induction of experimental bone loss. Ten OCX sham-operated rats were not subjected to experimental bone loss and served as healthy controls. The rats were euthanized two weeks later, so as to assess bone resorption and the production of inflammatory cytokines in the gingival tissue and serum. In order to study the in vitro impact of testosterone, osteoclasts were differentiated from RAW264.7 cells and testosterone was added at increasing concentrations. Both OCX and FLU increased bone resorption, but OCX alone was observed to increase osteoclast count. IL-1β production was increased only in the gingival tissue of OCX animals, whereas FLU-treated animals presented a decreased expression of IL-6. Testosterone reduced the osteoclast formation in a dose-dependent manner, and significantly impacted the production of TNF-α; FLU partially reversed these actions. When taken together, our results indicate that testosterone modulates experimental bone loss, and that this action is mediated, at least in part, via the androgen receptor. PMID:26450018

  13. Androgen receptor blockade using flutamide skewed sex ratio of litters in mice

    PubMed Central

    Gharagozlou, Faramarz; Youssefi, Reza; Vojgani, Mehdi; Akbarinejad, Vahid; Rafiee, Ghazaleh

    2016-01-01

    Maternal testosterone has been indicated to affect sex ratio of offspring. The present study was conducted to elucidate the role of androgen receptor in this regard by blockade of androgen receptor using flutamide in female mice. Mice were randomly assigned to two experimental groups. Mice in the control (n = 20) and treatment (n = 20) groups received 8 IU equine chorionic gonadotropin (eCG) followed by human chorionic gonadotropin (hCG) injection (8 IU) 47 hr later. In addition, mice in the control and treatment groups received four injections of ethanol-saline vehicle and flutamide solution (2.50 mg), respectively, started from 1 hr before eCG injection until hCG injection at 12-hr intervals. Conception rate was not different between the treatment (18/20: 90.00%) and control (19/20: 95.00%) groups (p > 0.05). Litter size was higher in the treatment (8.22 ± 0.26) than control (7.21 ± 0.28) group (p < 0.05). Male sex ratio was lower in the flutamide-treated mice (67/148: 45.30%) as compared with the untreated ones (80/137: 58.40%; odds ratio = 1.69; p < 0.05). In conclusion, the results showed that androgen receptor blockade could skew sex ratio of offspring toward females implying that the effect of testosterone on sex ratio might be through binding to androgen receptor. In addition, the blockade of androgen receptor using flutamide appeared to enhance litter size. PMID:27482363

  14. Endocrine disruptors differently influence estrogen receptor β and androgen receptor in male and female rat VSMC.

    PubMed

    Pellegrini, Marco; Bulzomi, Pamela; Lecis, Marco; Leone, Stefano; Campesi, Ilaria; Franconi, Flavia; Marino, Maria

    2014-08-01

    Sex steroid hormones differently control the major physiological processes in male and female organisms. In particular, their effects on vascular smooth muscle cells (VSMCs) migration are at the root of sex/gender-related differences reported in the cardiovascular system. Several exogenous substances, defined endocrine disruptor chemicals (EDCs), could interfere with these androgen and estrogen effects; however, the sex/gender-related susceptibility of VSMC motility to EDCs is completely unknown. Here, the effect of naturally occurring (naringenin, Nar) and synthetic (bisphenol A, BPA) EDCs on male and female VSMC motility has been evaluated. 17β-estradiol (E2, 0.1 nM-1 µM) induced a dose-dependent inhibition of motility in female-derived VSMC. In contrast, neither dihydrotestosterone (DHT, 0.01-100 nM) nor the common precursor of sex steroid hormones, testosterone (Tes, 0.01-100 nM) modified male-derived VSMC motility. Estrogen receptor (ER) β subtype-dependent activation of p38 was necessary for the E2 effect on cell motility. High BPA concentration prevented E2 effects in female-derived cells being without any effect in male-derived cells. Nar mimicked E2 effects on female-derived cells even in the presence of E2 or BPA. Intriguingly, Nar also inhibited the male-derived VSMC mobility. This latter effect was prevented by ERβ inhibitor, but not by the androgen receptor (AR) inhibitor. As a whole, ERβ-dependent signals in VSMC results more susceptible to the impact of EDCs than AR signals suggesting a possible high and overall susceptibility of female to EDCs. However, several male-derived cells, including VSMC, express ERβ, which could also serve as target of EDC disruption in male organisms. PMID:24347325

  15. CLONING, EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR ALPHA FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    In vitro screening assays designed to identify hormone mimics or antagonists, including those recommended for use in the EPA's Tier 1 screening battery, typically use mammalian estrogen (ER) and androgen receptors (AR) such as rat or human. Although we know that the amino acid s...

  16. Complete androgen insensitivity syndrome caused by a deep intronic pseudoexon-activating mutation in the androgen receptor gene.

    PubMed

    Känsäkoski, Johanna; Jääskeläinen, Jarmo; Jääskeläinen, Tiina; Tommiska, Johanna; Saarinen, Lilli; Lehtonen, Rainer; Hautaniemi, Sampsa; Frilander, Mikko J; Palvimo, Jorma J; Toppari, Jorma; Raivio, Taneli

    2016-01-01

    Mutations in the X-linked androgen receptor (AR) gene underlie complete androgen insensitivity syndrome (CAIS), the most common cause of 46,XY sex reversal. Molecular genetic diagnosis of CAIS, however, remains uncertain in patients who show normal coding region of AR. Here, we describe a novel mechanism of AR disruption leading to CAIS in two 46,XY sisters. We analyzed whole-genome sequencing data of the patients for pathogenic variants outside the AR coding region. Patient fibroblasts from the genital area were used for AR cDNA analysis and protein quantification. Analysis of the cDNA revealed aberrant splicing of the mRNA caused by a deep intronic mutation (c.2450-118A>G) in the intron 6 of AR. The mutation creates a de novo 5' splice site and a putative exonic splicing enhancer motif, which leads to the preferential formation of two aberrantly spliced mRNAs (predicted to include a premature stop codon). Patient fibroblasts contained no detectable AR protein. Our results show that patients with CAIS and normal AR coding region need to be examined for deep intronic mutations that can lead to pseudoexon activation. PMID:27609317

  17. Anabolic-androgenic steroid interaction with rat androgen receptor in vivo and in vitro: a comparative study.

    PubMed

    Feldkoren, Boris I; Andersson, Stefan

    2005-04-01

    Anabolic steroids are synthetic derivatives of testosterone and are characterized by their ability to cause nitrogen retention and positive protein metabolism, thereby leading to increased protein synthesis and muscle mass. There are disagreements in the literature in regards to the interaction of anabolic steroids with the androgen receptor (AR) as revealed by competitive ligand binding assays in vitro using cytosolic preparations from prostate and skeletal muscle. By use of tissue extracts, it has been shown that some anabolic steroids have binding affinities for the AR that are higher than that of the natural androgen testosterone, while others such as stanozolol and methanedienone have significantly lower affinities as compared with testosterone. In this study we show that stanozolol and methanedienone are low affinity ligands of the rat recombinant AR as revealed by a ligand binding assay in vitro, however, based on a cell-based AR-dependent transactivation assay, they are potent activators of the AR. We also show that a single injection of stanozolol and methanedienone causes a rapid cytosolic depletion of AR in rat skeletal muscle. Based on these results, we conclude that anabolic steroids with low affinity to AR in vitro, can in fact in vivo act on the AR to cause biological responses. PMID:15876413

  18. Complete androgen insensitivity syndrome caused by a deep intronic pseudoexon-activating mutation in the androgen receptor gene

    PubMed Central

    Känsäkoski, Johanna; Jääskeläinen, Jarmo; Jääskeläinen, Tiina; Tommiska, Johanna; Saarinen, Lilli; Lehtonen, Rainer; Hautaniemi, Sampsa; Frilander, Mikko J.; Palvimo, Jorma J.; Toppari, Jorma; Raivio, Taneli

    2016-01-01

    Mutations in the X-linked androgen receptor (AR) gene underlie complete androgen insensitivity syndrome (CAIS), the most common cause of 46,XY sex reversal. Molecular genetic diagnosis of CAIS, however, remains uncertain in patients who show normal coding region of AR. Here, we describe a novel mechanism of AR disruption leading to CAIS in two 46,XY sisters. We analyzed whole-genome sequencing data of the patients for pathogenic variants outside the AR coding region. Patient fibroblasts from the genital area were used for AR cDNA analysis and protein quantification. Analysis of the cDNA revealed aberrant splicing of the mRNA caused by a deep intronic mutation (c.2450-118A>G) in the intron 6 of AR. The mutation creates a de novo 5′ splice site and a putative exonic splicing enhancer motif, which leads to the preferential formation of two aberrantly spliced mRNAs (predicted to include a premature stop codon). Patient fibroblasts contained no detectable AR protein. Our results show that patients with CAIS and normal AR coding region need to be examined for deep intronic mutations that can lead to pseudoexon activation. PMID:27609317

  19. [Transdisciplinary Approach for Sarcopenia. Appication of selective androgen receptor modulator to the therapy of sarcopenia].

    PubMed

    Yanase, Toshihiko; Tanabe, Makito; Nomiyama, Takashi

    2014-10-01

    The research to develop a drug, so called selective androgen receptor modulator (SARM) , which shows beneficial androgenic action on bone and muscle, but hardly possesses the stimulatory action on prostate has been making a progress. However, no drug is available in the market at present. Most of such drugs are developed, aiming at the application to age-related muscle reduction (sarcopenia) and osteoporosis. Recently, in a clinical trial of SARM (enbosarm) administration to healthy elderly men, a promising data showing the increase of lean body mass and physical function has been reported. Future clinical applications of SARMs are expected. PMID:25266096

  20. New single nucleotide variation in the promoter region of androgen receptor (AR) gene in hypospadic patients

    PubMed Central

    Borhani, Nasim; Ghaffari Novin, Marefat; Manoochehri, Mehdi; Rouzrokh, Mohsen; Kazemi, Bahram; Koochaki, Ameneh; Hosseini, Ahmad; Masteri Farahani, Reza; Omrani, Mir Davood

    2014-01-01

    Background: Hypospadias is one of the most common congenital abnormalities in the male which is characterized by altered development of urethra, foreskin and ventral surface of the penis. Androgen receptor gene plays a critical role in the development of the male genital system by mediating the androgens effects. Objective: In present study, we looked for new variations in androgen receptor promoter and screened its exon 1 for five single nucleotide polymorphisms (SNP) in healthy and hypospadias Iranian men. Materials and Methods: In our study, at first DNA was extracted from patients (n=100) and controls (n=100) blood samples. Desired fragments of promoter and exon 1 were amplified using polymerase chain reaction. The promoter region was sequenced for the new variation and exone 1 screened for five SNPs (rs139767835, rs78686797, rs62636528, rs62636529, rs145326748) using restriction fragment length polymorphism technique. Results: The results showed a new single nucleotide variation (C→T) at -480 of two patients’ promoter region (2%). None of the mentioned SNPs were detected in patients and controls groups (0%). Conclusion: This finding indicates that new single nucleotide polymorphism in androgen receptor promoter may have role in etiology of hypospadias and development of this anomaly. This article extracted from Ph.D. thesis. (Nasim Borhani) PMID:24799883

  1. Mutated human androgen receptor gene detected in a prostatic cancer patient is also activated by estradiol

    SciTech Connect

    Elo, J.P.; Kvist, L.; Leinonen, K.; Isomaa, V.

    1995-12-01

    Androgens are necessary for the development of prostatic cancer. The mechanisms by which the originally androgen-dependent prostatic cancer cells are relieved of the requirement to use androgen for their growth are largely unknown. The human prostatic cancer cell line LNCaP has been shown to contain a point mutation in the human androgen receptor gene (hAR), suggesting that changes in the hAR may contribute to the abnormal hormone response of prostatic cells. To search for point mutations in the hAR, we used single strand conformation polymorphism analysis and a polymerase chain reaction direct sequencing method to screen 23 prostatic cancer specimens from untreated patients, 6 prostatic cancer specimens from treated patients, and 11 benign prostatic hyperplasia specimens. One mutation was identified in DNA isolated from prostatic cancer tissue, and the mutation was also detected in the leukocyte DNA of the patient and his offspring. The mutation changed codon 726 in exon E from arginine to leucine and was a germ line mutation. The mutation we found in exon E of the hAR gene does not alter the ligand binding specificity of the AR, but the mutated receptor was activated by estradiol to a significantly greater extent than the wild-type receptor. The AR gene mutation described in this study might be one explanation for the altered biological activity of prostatic cancer. 36 refs., 4 figs.

  2. Blockade of androgen receptor in the medial amygdala inhibits noncontact erections in male rats.

    PubMed

    Bialy, Michal; Nikolaev-Diak, Anna; Kalata, Urszula; Nikolaev, Evgeni

    2011-06-01

    Our previous work demonstrated that androgens in the medial amygdala (MeA) of castrated male rats maintained noncontact erections (NCEs), which occur during exposure to an inaccessible receptive female, for one week after implantation. The present experiments investigated the effects of implantation into the MeA of either flutamide (F), a blocker of androgen receptors, or of 1,4,6-androstatrien-3,17-dione (ATD), which blocks aromatization of testosterone. One day after implantation of F, fewer males displayed NCEs, and had longer latencies to the first NCE and fewer NCEs, and spent less total time in genital grooming, compared to the control group. ATD had only weak facilitative effects on some measures of NCEs. These results suggest that androgen receptors in the MeA play a major role in the regulation of NCEs and that the MeA is one of the neuronal structures that regulate male sexual arousal. Furthermore, it is sensitive to relatively fast changes in the level of androgen receptors stimulation. PMID:21315100

  3. Equol inhibits prostate cancer growth through degradation of androgen receptor by S-phase kinase-associated protein 2.

    PubMed

    Itsumi, Momoe; Shiota, Masaki; Takeuchi, Ario; Kashiwagi, Eiji; Inokuchi, Junichi; Tatsugami, Katsunori; Kajioka, Shunichi; Uchiumi, Takeshi; Naito, Seiji; Eto, Masatoshi; Yokomizo, Akira

    2016-07-01

    Chemopreventive and potential therapeutic effects of soy isoflavones have been shown to be effective in numerous preclinical studies as well as clinical studies in prostate cancer. Although the inhibition of androgen receptor signaling has been supposed as one mechanism underlying their effects, the precise mechanism of androgen receptor inhibition remains unclear. Thus, this study aimed to clarify their mechanism. Among soy isoflavones, equol suppressed androgen receptor as well as prostate-specific antigen expression most potently in androgen-dependent LNCaP cells. However, the inhibitory effect on androgen receptor expression and activity was less prominent in castration-resistant CxR and 22Rv1 cells. Consistently, cell proliferation was suppressed and cellular apoptosis was induced by equol in LNCaP cells, but less so in CxR and 22Rv1 cells. We revealed that the proteasome pathway through S-phase kinase-associated protein 2 (Skp2) was responsible for androgen receptor suppression. Taken together, soy isoflavones, especially equol, appear to be promising as chemopreventive and therapeutic agents for prostate cancer based on the fact that equol augments Skp2-mediated androgen receptor degradation. Moreover, because Skp2 expression was indicated to be crucial for the effect of soy isoflavones, soy isoflavones may be applicable for precancerous and cancerous prostates. PMID:27088761

  4. Restoration of the cellular secretory milieu overrides androgen dependence of in vivo generated castration resistant prostate cancer cells overexpressing the androgen receptor.

    PubMed

    Patki, Mugdha; Huang, Yanfang; Ratnam, Manohar

    2016-07-22

    It is believed that growth of castration resistant prostate cancer (CRPC) cells is enabled by sensitization to minimal residual post-castrate androgen due to overexpression of the androgen receptor (AR). Evidence is derived from androgen-induced colony formation in the absence of cell-secreted factors or from studies involving forced AR overexpression in hormone-dependent cells. On the other hand, standard cell line models established from CRPC patient tumors (e.g., LNCaP and VCaP) are hormone-dependent and require selection pressure in castrated mice to re-emerge as CRPC cells and the resulting tumors then tend to be insensitive to the androgen antagonist enzalutamide. Therefore, we examined established CRPC model cells produced by castration of mice bearing hormone-dependent cell line xenografts including CRPC cells overexpressing full-length AR (C4-2) or co-expressing wtAR and splice-variant AR-V7 that is incapable of ligand binding (22Rv1). In standard colony formation assays, C4-2 cells were shown to be androgen-dependent and sensitive to enzalutamide whereas 22Rv1 cells were incapable of colony formation under identical conditions. However, both C4-2 and 22Rv1 cells formed colonies in conditioned media derived from the same cells or from HEK293 fibroblasts that were proven to lack androgenic activity. This effect was (i) not enhanced by androgen, (ii) insensitive to enzalutamide, (iii) dependent on AR (in C4-2) and on AR-V7 and wtAR (in 22Rv1) and (iv) sensitive to inhibitors of several signaling pathways, similar to androgen-stimulation. Therefore, during progression to CRPC in vivo, coordinate cellular changes accompanying overexpression of AR may enable cooperation between hormone-independent activity of AR and actions of cellular secretory factors to completely override androgen-dependence and sensitivity to drugs targeting hormonal factors. PMID:27179779

  5. AB46. Screening and identification for the target genes of androgen receptor in mouse Sertoli cells

    PubMed Central

    Gui, Yaoting; Mou, Lisha; Zhang, Qiaoxia; Yang, Lihua; Wang, Yadong; Cai, Zhiming

    2014-01-01

    Androgen and androgen receptor (AR) play important roles in spermatogenesis, yet detailed androgen/AR signals in Sertoli cells remain unclear. To identify AR target genes in Sertoli cells, we analyzed the gene expression profiles of testis between mice lacking AR in Sertoli cells (S-AR) and their littermate wild-type (WT) mice. Digital gene expression analysis identified 2,276 genes downregulated and 2,865 genes upregulated in the S-AR mice testis compared to WT ones. To further nail down the difference within Sertoli cells, we first constructed Sertoli cell line TM4 with stably transfected AR (named as TM4/AR) and found androgens failed to transactivate AR in Sertoli TM4 and TM4/AR cells. Interestingly, additional transient transfection of AR-cDNA resulted in significant androgen responsiveness with TM4/AR cells showing ten times more androgen sensitivity than TM4 cells. In the condition where maximal androgen response was demonstrated, we then analyzed gene expression and found the expression levels of 2313 genes were changed more than twofold by transient transfection of AR-cDNA in the presence of testosterone. Among these genes, 603 androgen-/AR-regulated genes, including 164 up-regulated and 439 down-regulated, were found in both S-AR mice testis and TM4/AR cells. Ubiquitin-conjugating enzyme E2B (Ube2b) is one of the regulated genes from the digital gene expression analysis. The expression of UBE2B was decreased in the testes of the S-AR mice analyzed by quantitative RT-PCR (qRT-PCR) and immunofluorescence. The up-regulation of Ube2b gene by testosterone was further demonstrated by Western blot and qRT-PCR in TM4 cells. Moreover, luciferase assay, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay validated that the ligand-bound AR activated Ube2b transcription via directly binding to the androgen-responsive element of the Ube2b promoter. In vitro analyses showed that testosterone increased UBE2B expression and activated H2A

  6. Androgen Receptor as a Driver of Therapeutic Resistance in Advanced Prostate Cancer

    PubMed Central

    Kahn, Barbara; Collazo, Joanne; Kyprianou, Natasha

    2014-01-01

    The role of the androgen receptor (AR) signaling axis in the progression of prostate cancer is a cornerstone to our understanding of the molecular mechanisms causing castration-resistant prostate cancer (CRPC). Resistance of advanced prostate cancer to available treatment options makes it a clinical challenge that results in approximately 30,000 deaths of American men every year. Since the historic discovery by Dr. Huggins more than 70 years ago, androgen deprivation therapy (ADT) has been the principal treatment for advanced prostate cancer. Initially, ADT induces apoptosis of androgen-dependent prostate cancer epithelial cells and regression of androgen-dependent tumors. However, the majority of patients with advanced prostate cancer progress and become refractory to ADT due to emergence of androgen-independent prostate cancer cells driven by aberrant AR activation. Microtubule-targeting agents such as taxanes, docetaxel and paclitaxel, have enjoyed success in the treatment of metastatic prostate cancer; although new, recently designed mitosis-specific agents, such as the polo-kinase and kinesin-inhibitors, have yielded clinically disappointing results. Docetaxel, as a first-line chemotherapy, improves prostate cancer patient survival by months, but tumor resistance to these therapeutic agents inevitably develops. On a molecular level, progression to CRPC is characterized by aberrant AR expression, de novo intraprostatic androgen production, and cross talk with other oncogenic pathways. Emerging evidence suggests that reactivation of epithelial-mesenchymal-transition (EMT) processes may facilitate the development of not only prostate cancer but also prostate cancer metastases. EMT is characterized by gain of mesenchymal characteristics and invasiveness accompanied by loss of cell polarity, with an increasing number of studies focusing on the direct involvement of androgen-AR signaling axis in EMT, tumor progression, and therapeutic resistance. In this article, we

  7. Mental rotation in intellectually gifted boys is affected by the androgen receptor CAG repeat polymorphism.

    PubMed

    Durdiaková, Jaroslava; Lakatošová, Silvia; Kubranská, Aneta; Laznibatová, Jolana; Ficek, Andrej; Ostatníková, Daniela; Celec, Peter

    2013-08-01

    Testosterone was shown to organize brain and modulate cognitive functions. It is currently unknown whether mental rotation is also associated with prenatal testosterone exposure and testosterone-related genetic polymorphisms. The aim of our study was to analyze associations between mental rotation performance, the actual testosterone levels, the prenatal testosterone level (expressed as 2D:4D ratio) and the androgen receptor CAG repeat polymorphism in intellectually gifted boys. One hundred forty-seven boys aged 10-18 years with IQ>130 were enrolled. Saliva samples were collected and used for ELISA of actual levels of salivary testosterone. The 2D:4D finger length ratio as an indicator of prenatal testosterone was measured on both hands and averaged. Amthauer mental rotation test was used for the assessment of this spatial ability. The CAG repeat polymorphism in the androgen receptor gene was analyzed using PCR and capillary electrophoresis. Linear regression revealed that 2D:4D finger length ratio and the number of CAG repeats in the androgen receptor gene were associated with mental rotation. Actual levels of testosterone did not correlate significantly with mental rotation. Multivariate analysis of covariance revealed that after adjustment of age as a confounding variable, only the effect of the genetic polymorphism was significant. The results are in line with our previous genetic analysis of intellectually gifted boys showing the importance of CAG repeat polymorphism in the androgen receptor gene. Details of the interactions between androgen signaling, testosterone levels and its metabolism especially during the prenatal development of brain function remain to be elucidated. PMID:23727571

  8. Targeting the androgen receptor in prostate and breast cancer – several new agents in development

    PubMed Central

    Proverbs-Singh, Tracy; Feldman, Jarett L.; Morris, Michael J.; Autio, Karen A.; Traina, Tiffany A.

    2016-01-01

    Prostate cancer and breast cancer share similarities as hormone-sensitive cancers with a wide heterogeneity of both phenotype and biology. The androgen receptor (AR) is a hormone receptor involved in both benign and malignant processes. Targeting androgen synthesis and the AR pathway has been and remains central to prostate cancer therapy. Recently, there is increased interest in the role of the AR in breast cancer development and growth, with data suggesting AR co-expression with estrogen, progesterone and human epidermal growth factor receptors, across all intrinsic subtypes of breast cancer. Targeting the AR axis is an evolving field with novel therapies in development which may ultimately be applicable for both tumor types. In this review, we offer an overview of available agents which target the AR axis in both prostate and breast cancer and provide insight into the novel drugs in development for targeting this signaling pathway. PMID:25722318

  9. Green tea polyphenol EGCG blunts androgen receptor function in prostate cancer

    PubMed Central

    Siddiqui, Imtiaz A.; Asim, Mohammad; Hafeez, Bilal B.; Adhami, Vaqar M.; Tarapore, Rohinton S.; Mukhtar, Hasan

    2011-01-01

    Androgen deprivation therapy is the major treatment for advanced prostate cancer (PCa). However, it is a temporary remission, and the patients almost inevitably develop hormone refractory prostate cancer (HRPC). HRPC is almost incurable, although most HRPC cells still express androgen receptor (AR) and depend on the AR for growth, making AR a prime drug target. Here, we provide evidence that epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, is a direct antagonist of androgen action. In silico modeling and FRET-based competition assay showed that EGCG physically interacts with the ligand-binding domain of AR by replacing a high-affinity labeled ligand (IC50 0.4 μM). The functional consequence of this interaction was a decrease in AR-mediated transcriptional activation, which was due to EGCG mediated inhibition of interdomain N-C termini interaction of AR. Treatment with EGCG also repressed the transcriptional activation by a hotspot mutant AR (T877A) expressed ectopically as well as the endogenous AR mutant. As the physiological consequence of AR antagonism, EGCG repressed R1881-induced PCa cell growth. In a xenograft model, EGCG was found to inhibit AR nuclear translocation and protein expression. We also observed a significant down-regulation of androgen-regulated miRNA-21 and up-regulation of a tumor suppressor, miRNA-330, in tumors of mice treated with EGCG. Taken together, we provide evidence that EGCG functionally antagonizes androgen action at multiple levels, resulting in inhibition of PCa growth.—Siddiqui, I. A., Asim, M., Hafeez, B. B., Adhami, V. M., Tarapore, R. S., Mukhtar, H. Green tea polyphenol EGCG blunts androgen receptor function in prostate cancer. PMID:21177307

  10. Testosterone regulates keratin 33B expression in rat penis growth through androgen receptor signaling

    PubMed Central

    Ma, Yan-Min; Wu, Kai-Jie; Dang, Qiang; Shi, Qi; Gao, Yang; Guo, Peng; Xu, Shan; Wang, Xin-Yang; He, Da-Lin; Gong, Yong-Guang

    2014-01-01

    Androgen therapy is the mainstay of treatment for the hypogonadotropic hypogonadal micropenis because it obviously enhances penis growth in prepubescent microphallic patients. However, the molecular mechanisms of androgen treatment leading to penis growth are still largely unknown. To clarify this well-known phenomenon, we successfully generated a castrated male Sprague Dawley rat model at puberty followed by testosterone administration. Interestingly, compared with the control group, testosterone treatment stimulated a dose-dependent increase of penis weight, length, and width in castrated rats accompanied with a dramatic recovery of the pathological changes of the penis. Mechanistically, testosterone administration substantially increased the expression of androgen receptor (AR) protein. Increased AR protein in the penis could subsequently initiate transcription of its target genes, including keratin 33B (Krt33b). Importantly, we demonstrated that KRT33B is generally expressed in the rat penis and that most KRT33B expression is cytoplasmic. Furthermore, AR could directly modulate its expression by binding to a putative androgen response element sequence of the Krt33b promoter. Overall, this study reveals a novel mechanism facilitating penis growth after testosterone treatment in precastrated prepubescent animals, in which androgen enhances the expression of AR protein as well as its target genes, such as Krt33b. PMID:24994782

  11. A novel selective androgen receptor modulator, NEP28, is efficacious in muscle and brain without serious side effects on prostate.

    PubMed

    Akita, Kazumasa; Harada, Koichiro; Ichihara, Junji; Takata, Naoko; Takahashi, Yasuhiko; Saito, Koichi

    2013-11-15

    Age-related androgen depletion is known to be a risk factor for various diseases, such as osteoporosis and sarcopenia. Furthermore, recent studies have demonstrated that age-related androgen depletion results in accumulation of β-amyloid protein and thereby acts as a risk factor for the development of Alzheimer's disease. Supplemental androgen therapy has been shown to be efficacious in treating osteoporosis and sarcopenia. In addition, studies in animals have demonstrated that androgens can play a protective role against Alzheimer's disease. However, androgen therapy is not used routinely for these indications, because of side effects. Selective androgen receptor modulators (SARMs) are a new class of compounds. SARMs maintain the beneficial effects of androgens on bone and muscle while reducing unwanted side effects. NEP28 is a new SARM exhibiting high selectivity for androgen receptor. To investigate the pharmacological effects of NEP28, we compared the effects on muscle, prostate, and brain with mice that were androgen depleted by orchidectomy and then treated with either placebo, NEP28, dihydrotestosterone, or methyltestosterone. We demonstrated that NEP28 showed tissue-selective effect equivalent to or higher than existing SARMs. In addition, the administration of NEP28 increased the activity of neprilysin, a known Aβ-degrading enzyme. These results indicate that SARM is efficacious for the treatment of not only osteoporosis and sarcopenia, but also Alzheimer's disease. PMID:24177288

  12. Androgen insensitivity.

    PubMed

    Gottlieb, B; Pinsky, L; Beitel, L K; Trifiro, M

    1999-12-29

    The androgen receptor (AR) protein regulates transcription of certain genes. Usually, this activity depends upon a central DNA-binding domain that permits the binding of androgen-AR complexes to regulatory DNA sequences near or in a target gene. The AR also has a C-terminal androgen-binding domain (ABD) and an N-terminal modulatory domain. These domains interact among themselves and with coregulatory, nonreceptor proteins to determine vector control over a gene's transcription rate. The precise roles of these proteins are active research areas. Severe X-linked androgen receptor gene (AR) mutations cause complete androgen insensitivity, mild ones impair virilization with or without infertility, and moderate ones sometimes yield a wide phenotypic spectrum among sibs. Different expressivity may reflect variability of AR-interactive proteins. The family history must identify heterozygous XX females with sparse, delayed, or asymmetric pubic/axillary hair or delayed menarche and infertile XY maternal aunts or uncles. Mutation type and density vary along the length of the AR. N-terminal polyglutamine tract expansion limits AR transactivation, causing a form of mild androgen insensitivity. Analysis of ABD mutations that do not impair androgen binding or impair it selectively will illuminate its intradomain properties. For partial androgen insensitivity and mild androgen insensitivity, pharmacotherapy with certain androgens or other steroids may overcome some dysfunction of certain mutant ARs. Experience with this approach is limited; outcomes have been generally disappointing. PMID:10727996

  13. Testosterone signaling through internalizable surface receptors in androgen receptor-free macrophages.

    PubMed

    Benten, W P; Lieberherr, M; Stamm, O; Wrehlke, C; Guo, Z; Wunderlich, F

    1999-10-01

    Testosterone acts on cells through intracellular transcription-regulating androgen receptors (ARs). Here, we show that mouse IC-21 macrophages lack the classical AR yet exhibit specific nongenomic responses to testosterone. These manifest themselves as testosterone-induced rapid increase in intracellular free [Ca(2+)], which is due to release of Ca(2+) from intracellular Ca(2+) stores. This Ca(2+) mobilization is also inducible by plasma membrane-impermeable testosterone-BSA. It is not affected by the AR blockers cyproterone and flutamide, whereas it is completely inhibited by the phospholipase C inhibitor U-73122 and pertussis toxin. Binding sites for testosterone are detectable on the surface of intact IC-21 cells, which become selectively internalized independent on caveolae and clathrin-coated vesicles upon agonist stimulation. Internalization is dependent on temperature, ATP, cytoskeletal elements, phospholipase C, and G-proteins. Collectively, our data provide evidence for the existence of G-protein-coupled, agonist-sequestrable receptors for testosterone in plasma membranes, which initiate a transcription-independent signaling pathway of testosterone. PMID:10512854

  14. Testosterone Signaling through Internalizable Surface Receptors in Androgen Receptor-free Macrophages

    PubMed Central

    Benten, W. Peter M.; Lieberherr, Michèle; Stamm, Olaf; Wrehlke, Christian; Guo, Zhiyong; Wunderlich, Frank

    1999-01-01

    Testosterone acts on cells through intracellular transcription-regulating androgen receptors (ARs). Here, we show that mouse IC-21 macrophages lack the classical AR yet exhibit specific nongenomic responses to testosterone. These manifest themselves as testosterone-induced rapid increase in intracellular free [Ca2+], which is due to release of Ca2+ from intracellular Ca2+ stores. This Ca2+ mobilization is also inducible by plasma membrane-impermeable testosterone-BSA. It is not affected by the AR blockers cyproterone and flutamide, whereas it is completely inhibited by the phospholipase C inhibitor U-73122 and pertussis toxin. Binding sites for testosterone are detectable on the surface of intact IC-21 cells, which become selectively internalized independent on caveolae and clathrin-coated vesicles upon agonist stimulation. Internalization is dependent on temperature, ATP, cytoskeletal elements, phospholipase C, and G-proteins. Collectively, our data provide evidence for the existence of G-protein-coupled, agonist-sequestrable receptors for testosterone in plasma membranes, which initiate a transcription-independent signaling pathway of testosterone. PMID:10512854

  15. Tissue-specific pioneer factors associate with androgen receptor cistromes and transcription programs

    PubMed Central

    Pihlajamaa, Päivi; Sahu, Biswajyoti; Lyly, Lauri; Aittomäki, Viljami; Hautaniemi, Sampsa; Jänne, Olli A

    2014-01-01

    Androgen receptor (AR) binds male sex steroids and mediates physiological androgen actions in target tissues. ChIP-seq analyses of AR-binding events in murine prostate, kidney and epididymis show that in vivo AR cistromes and their respective androgen-dependent transcription programs are highly tissue specific mediating distinct biological pathways. This high order of tissue specificity is achieved by the use of exclusive collaborating factors in the three androgen-responsive tissues. We find two novel collaborating factors for AR signaling in vivo—Hnf4α (hepatocyte nuclear factor 4α) in mouse kidney and AP-2α (activating enhancer binding protein 2α) in mouse epididymis—that define tissue-specific AR recruitment. In mouse prostate, FoxA1 serves for the same purpose. FoxA1, Hnf4α and AP-2α motifs are over-represented within unique AR-binding loci, and the cistromes of these factors show substantial overlap with AR-binding events distinct to each tissue type. These licensing or pioneering factors are constitutively bound to chromatin and guide AR to specific genomic loci upon hormone exposure. Collectively, liganded receptor and its DNA-response elements are required but not sufficient for establishment of tissue-specific transcription programs. PMID:24451200

  16. Effect of Small Molecules Modulating Androgen Receptor (SARMs) in Human Prostate Cancer Models

    PubMed Central

    Tesei, Anna; Leonetti, Carlo; Di Donato, Marzia; Gabucci, Elisa; Porru, Manuela; Varchi, Greta; Guerrini, Andrea; Amadori, Dino; Arienti, Chiara; Pignatta, Sara; Paganelli, Giulia; Caraglia, Michele; Castoria, Gabriella; Zoli, Wainer

    2013-01-01

    The management of hormone-refractory prostate cancer represents a major challenge in the therapy of this tumor, and identification of novel androgen receptor antagonists is needed to render treatment more effective. We analyzed the activity of two novel androgen receptor antagonists, (S)-11 and (R)-9, in in vitro and in vivo experimental models of hormone-sensitive or castration-resistant prostate cancer (CRPC). In vitro experiments were performed on LNCaP, LNCaP-AR, LNCaP-Rbic and VCaP human prostate cancer cells. Cytotoxic activity was assessed by SRB and BrdU uptake, AR transactivation by luciferase reporter assay and PSA levels by Real Time RT-PCR and ELISA assays. Cell cycle progression-related markers were evaluated by western blot. In vivo experiments were performed on SCID mice xenografted with cells with different sensitivity to hormonal treatment. In hormone-sensitive LNCaP and LNCaP-AR cells, the latter expressing high androgen receptor levels, (R)-9 and (S)-11 exhibited a higher cytotoxic effect compared to that of the reference compound ((R)-bicalutamide), also in the presence of the synthetic androgen R1881. Furthermore, the cytotoxic effect produced by (R)-9 was higher than that of (S)-11 in the two hormone-resistant LNCaP-AR and VCaP cells. A significant reduction in PSA levels was observed after exposure to both molecules. Moreover, (S)-11 and (R)-9 inhibited DNA synthesis by blocking the androgen-induced increase in cyclin D1 protein levels. In vivo studies on the toxicological profile of (R)-9 did not reveal the presence of adverse events. Furthermore, (R)-9 inhibited tumor growth in various in vivo models, especially LNCaP-Rbic xenografts, representative of recurrent disease. Our in vitro results highlight the antitumor activity of the two novel molecules (R)-9 and (S)-11, making them a potentially attractive option for the treatment of CRPC. PMID:23667504

  17. Pharmacological characterization of an imidazolopyrazole as novel selective androgen receptor modulator.

    PubMed

    Zhang, Xuqing; Allan, George F; Tannenbaum, Pamela; Sbriscia, Tifanie; Linton, Olivia; Lai, Muh-Tsann; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Lundeen, Scott G; Sui, Zhihua

    2013-03-01

    Selective androgen receptor modulators (SARMs) are androgens with tissue-selective activity. SARMs that have anabolic activity on muscle while having minimal stimulatory activity on prostate are classified as SARM agonists. They can be used to prevent the loss of lean body mass that is associated with cancer, immunodeficiency, renal disease and aging. They may also have anabolic activity on bone; thus, unlike estrogens, they may reverse the loss of bone strength associated with aging or hypogonadism. Our in-house effort on SARM program discovers a nonsteroidal androgen receptor ligand with a unique imidazolopyrazole moiety in its structure. In vitro, this compound is a weak androgen receptor binder and a weak androgen agonist. Despite this, in orchidectomized mature rats it is an effective SARM agonist, with an ED(50) on levator ani muscle of 3.3mg/kg and an ED(50) on ventral prostate of >30mg/kg. It has its maximal effect on muscle at the dose of 10mg/kg. In addition, this compound has mixed agonistic and antagonistic activities on prostate, reducing the weight of that tissue in intact rats by 22% at 10mg/kg. The compound does not have significant effect on gonadotropin levels or testosterone levels in both orchidectomized and intact male rats. It does not have notable progestin, estrogen or glucocorticoid agonistic or antagonistic activity in rats. In a female sexual behavior model, it improves the sexual desire of ovariectomized female rats for sexually mature intact males over nonsexually ovariectomized females. Overall, the imidazolopyrazole is a potent prostate-sparing candidate for development as a SARM agonist with an appropriate pharmacological profile for clinical benefit in muscle-wasting conditions and female sexual function disorders. PMID:23098693

  18. Structure of the ligand-binding domain (LBD) of human androgen receptor in complex with a selective modulator LGD2226

    SciTech Connect

    Wang, Feng; Liu, Xiao-qin; Li, He; Liang, Kai-ni; Miner, Jeffrey N.; Hong, Mei; Kallel, E. Adam; Oeveren, Arjan van; Zhi, Lin; Jiang, Tao

    2006-11-01

    Crystal structure of the ligand-binding domain of androgen receptor in complex with LGD2226. The androgen receptor (AR) is a ligand-inducible steroid hormone receptor that mediates androgen action, determining male sexual phenotypes and promoting spermatogenesis. As the androgens play a dominant role in male sexual development and function, steroidal androgen agonists have been used clinically for some years. However, there is a risk of potential side effects and most steroidal androgens cannot be dosed orally, which limits the use of these substances. 1,2-Dihydro-6-N,N-bis(2,2,2-trifluoroethyl) amino-4-trifluoromethyl-2-quinolinone (LGD2226) is a synthetic nonsteroidal ligand and a novel selective AR modulator. The crystal structure of the complex of LGD2226 with the androgen receptor ligand-binding domain (AR LBD) at 2.1 Å was solved and compared with the structure of the AR LBD–R1881 complex. It is hoped that this will aid in further explaining the selectivity of LGD2226 observed in in vitro and in vivo assays and in developing more selective and effective therapeutic agents.

  19. Androgen Receptors in a Cichlid Fish, Astatotilapia burtoni: Structure, Localization, and Expression Levels

    PubMed Central

    HARBOTT, LENE K.; BURMEISTER, SABRINA S.; WHITE, RICHARD B.; VAGELL, MIKE; FERNALD, RUSSELL D.

    2009-01-01

    Androgens are an important output of the hypothalamic-pituitary-gonadal (HPG) axis that controls reproduction in all vertebrates. In male teleosts two androgens, testosterone and 11-ketotestosterone, control sexual differentiation and development in juveniles and reproductive behavior in adults. Androgenic signals provide feedback at many levels of the HPG axis, including the hypothalamic neurons that synthesize and release gonadotropin-releasing hormone 1 (GnRH1), but the precise cellular site of androgen action in the brain is not known. Here we describe two androgen receptor subtypes, ARα and ARβ, in the cichlid Astatotilapia burtoni and show that these subtypes are differentially located throughout the adult brain in nuclei known to function in the control of reproduction. ARα was expressed in the ventral part of the ventral telencephalon, the preoptic area (POA) of the hypothalamus and the ventral hypothalamus, whereas ARβ was more widely expressed in the dorsal and ventral telencephalon, the POA, and the ventral and dorsal hypothalamus. We provide the first evidence in any vertebrate that the GnRH1-releasing neurons, which serve as the central control point of the HPG axis, express both subtypes of AR. Using quantitative real-time PCR, we show that A. burtoni AR subtypes have different expression levels in adult tissue, with ARα showing significantly higher expression than ARβ in the pituitary, and ARβ expressed at a higher level than ARα in the anterior and middle brain. These data provide important insight into the role of androgens in regulating the vertebrate reproductive axis. PMID:17614300

  20. Androgen Receptor Coactivators in Regulation of Growth and Differentiation in Prostate Cancer.

    PubMed

    Culig, Zoran

    2016-02-01

    Androgen receptor (AR) is a key factor in regulation of growth and differentiation in normal and malignant prostate. Endocrine therapies for prostate cancer include inhibition of androgen production either by analogs of luteinizing hormone releasing hormone or abiraterone acetate and/or use of anti-androgens such as hydroxyflutamide, bicalutamide, and enzalutamide. Castration therapy-resistant cancer develops inevitably in patients who undergo treatment. AR coactivators are proteins which interact with one or more regions of the AR thus enhancing its function. Although several functions of AR coactivators may be redundant, specific functions have been identified and analyzed. The p160 group of coactivators, SRC-1, -2, and -3 not only potentiate the activation of the AR, but are also implicated in potentiation of function of insulin-like growth factor-I and activation of the Akt pathway. Transcriptional integrators p300 and CBP are up-regulated by androgen ablation and may influence antagonist/agonist balance of non-steroidal anti-androgens. A therapy approach designed to target p300 in prostate cancer revealed its role in regulation of proliferation of migration of androgen-sensitive and -insensitive prostate cancer cells. Coactivators p300 and SRC-1 are required for AR activation by interleukin-6 (IL-6), a cytokine that is overexpressed in castration therapy-resistant prostate cancer. Some coactivators, such as Vav3, are involved in regulation of transcriptional activity of truncated AR, which emerge during endocrine thrapy. Stimulation of cellular migration and invasion by AR coactivators has also been described. Translational studies with aim to introduce anti-AR coactivator therapy have not been successfully implemented in the clinic so far. PMID:26201947

  1. Natural disordered sequences in the amino terminal domain of nuclear receptors: lessons from the androgen and glucocorticoid receptors.

    PubMed

    McEwan, Iain J; Lavery, Derek; Fischer, Katharina; Watt, Kate

    2007-01-01

    Steroid hormones are a diverse class of structurally related molecules, derived from cholesterol, that include androgens, estrogens, progesterone and corticosteroids. They represent an important group of physiologically active signalling molecules that bind intracellular receptor proteins and regulate genes involved in developmental, reproductive and metabolic processes. The receptor proteins share structurally and functionally related ligand binding and DNA-binding domains, but possess distinct N-terminal domains (NTD) of unique length and amino acids sequence. The NTD contains sequences important for gene regulation, exhibit structure plasticity and are likely to contribute to the specificity of the steroid hormone/receptor response. PMID:17464357

  2. Natural disordered sequences in the amino terminal domain of nuclear receptors: lessons from the androgen and glucocorticoid receptors

    PubMed Central

    McEwan, Iain J.; Lavery, Derek; Fischer, Katharina; Watt, Kate

    2007-01-01

    Steroid hormones are a diverse class of structurally related molecules, derived from cholesterol, that include androgens, estrogens, progesterone and corticosteroids. They represent an important group of physiologically active signalling molecules that bind intracellular receptor proteins and regulate genes involved in developmental, reproductive and metabolic processes. The receptor proteins share structurally and functionally related ligand binding and DNA-binding domains, but possess distinct N-terminal domains (NTD) of unique length and amino acids sequence. The NTD contains sequences important for gene regulation, exhibit structure plasticity and are likely to contribute to the specificity of the steroid hormone/receptor response. PMID:17464357

  3. Synthesis and biological evaluation of novel selective androgen receptor modulators (SARMs). Part I.

    PubMed

    Aikawa, Katsuji; Miyawaki, Toshio; Hitaka, Takenori; Imai, Yumi N; Hara, Takahito; Miyazaki, Junichi; Yamaoka, Masuo; Kusaka, Masami; Kanzaki, Naoyuki; Tasaka, Akihiro; Shiraishi, Mitsuru; Yamamoto, Satoshi

    2015-05-15

    To develop effective drugs for hypogonadism, sarcopenia, and cachexia, we designed, synthesized, and evaluated selective androgen receptor modulators (SARMs) that exhibit not only anabolic effects on organs such as muscles and the central nervous system (CNS) but also neutral or antagonistic effects on the prostate. Based on the information obtained from a docking model with androgen receptor (AR), we modified a hit compound A identified through high-throughput screening. Among the prepared compounds, 1-(4-cyano-1-naphthyl)-2,3-disubstituted pyrrolidine derivatives 17h, 17m, and 17j had highly potent AR agonistic activities in vitro and good tissue selectivity in vivo. These derivatives increased the weight of the levator ani muscle without influencing the prostate and seminal vesicle. In addition, these compounds induced sexual behavior in castrated rats, indicating that the compounds could also act as agonists on the CNS. PMID:25862209

  4. Structural Stereochemistry of Androstene Hormones Determines Interactions with Human Androgen, Estrogen, and Glucocorticoid Receptors

    PubMed Central

    Shaak, Thomas L.; Wijesinghe, Dayanjan S.; Chalfant, Charles E.; Diegelmann, Robert F.; Ward, Kevin R.; Loria, Roger M.

    2013-01-01

    DHEA, 17α-AED, 17β-AED, and 17β-AET exhibit strong biological activity that has been attributed to androgenic, estrogenic, or antiglucocorticoid activity in vivo and in vitro. This study compared DHEA, 17α-AED, 17β-AED, and 17β-AET for their ability to activate the human AR, ER, and GR and determine the relative androgenicity, estrogenicity, and glucocorticoid activity. The results show that, at the receptor level, these androstene hormones are weak AR and even weaker ER activators. Direct androstene hormone activation of the human AR, ERα, and ERβ may not be essential for their biological function. Similarly, these hormones indirectly activated the human GR, only in the presence of high dexamethasone concentrations. These results underscore the major difference between androstene hormone interactions with these nuclear receptors and their biological effects. PMID:24729874

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

    PubMed

    Pu, Yang; Xu, Meng; Liang, Yong; Yang, Kaiting; Guo, Yajun; Yang, Xuanming; Fu, Yang-Xin

    2016-04-01

    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. PMID:27053771

  6. N-Aryl-oxazolidin-2-imine Muscle Selective Androgen Receptor Modulators Enhance Potency through Pharmacophore Reorientation

    SciTech Connect

    Nirschl, Alexandra A.; Zou, Yan; Krystek, Jr., Stanley R.; Sutton, James C.; Simpkins, Ligaya M.; Lupisella, John A.; Kuhns, Joyce E.; Seethala, Ramakrishna; Golla, Rajasree; Sleph, Paul G.; Beehler, Blake C.; Grover, Gary J.; Egan, Donald; Fura, Aberra; Vyas, Viral P.; Li, Yi-Xin; Sack, John S.; Kish, Kevin F.; An, Yongmi; Bryson, James A.; Gougoutas, Jack Z.; DiMarco, John; Zahler, Robert; Ostrowski, Jacek; Hamann, Lawrence G.

    2010-11-09

    A novel selective androgen receptor modulator (SARM) scaffold was discovered as a byproduct obtained during synthesis of our earlier series of imidazolidin-2-ones. The resulting oxazolidin-2-imines are among the most potent SARMs known, with many analogues exhibiting sub-nM in vitro potency in binding and functional assays. Despite the potential for hydrolytic instability at gut pH, compounds of the present class showed good oral bioavailability and were highly active in a standard rodent pharmacological model.

  7. Utility of novel androgen receptor therapies in the real world: A nuanced approach.

    PubMed

    Dhawan, Mallika; Ryan, Charles J

    2016-08-01

    Abiraterone and enzalutamide are in widespread clinical use because of their favorable safety and efficacy. Nonetheless, even with newer agents, resistance develops overtime. In this review, we discuss mechanisms of resistance to these newer agents as well as novel therapeutic agents. We also review the literature to help clinicians decide which agent to begin with and when to stop or switch androgen receptor agents. PMID:27450893

  8. Androgen receptor-mediated non-genomic regulation of prostate cancer cell proliferation

    PubMed Central

    Liao, Ross S.; Ma, Shihong; Miao, Lu; Li, Rui; Yin, Yi

    2013-01-01

    Androgen receptor (AR)-mediated signaling is necessary for prostate cancer cell proliferation and an important target for therapeutic drug development. Canonically, AR signals through a genomic or transcriptional pathway, involving the translocation of androgen-bound AR to the nucleus, its binding to cognate androgen response elements on promoter, with ensuing modulation of target gene expression, leading to cell proliferation. However, prostate cancer cells can show dose-dependent proliferation responses to androgen within minutes, without the need for genomic AR signaling. This proliferation response known as the non-genomic AR signaling is mediated by cytoplasmic AR, which facilitates the activation of kinase-signaling cascades, including the Ras-Raf-1, phosphatidyl-inositol 3-kinase (PI3K)/Akt and protein kinase C (PKC), which in turn converge on mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) activation, leading to cell proliferation. Further, since activated ERK may also phosphorylate AR and its coactivators, the non-genomic AR signaling may enhance AR genomic activity. Non-genomic AR signaling may occur in an ERK-independent manner, via activation of mammalian target of rapamycin (mTOR) pathway, or modulation of intracellular Ca2+ concentration through plasma membrane G protein-coupled receptors (GPCRs). These data suggest that therapeutic strategies aimed at preventing AR nuclear translocation and genomic AR signaling alone may not completely abrogate AR signaling. Thus, elucidation of mechanisms that underlie non-genomic AR signaling may identify potential mechanisms of resistance to current anti-androgens and help developing novel therapies that abolish all AR signaling in prostate cancer. PMID:26816736

  9. Differential ligand selectivity of androgen receptors α and β from Murray-Darling rainbowfish (Melanotaenia fluviatilis).

    PubMed

    Bain, Peter A; Ogino, Yukiko; Miyagawa, Shinichi; Iguchi, Taisen; Kumar, Anupama

    2015-02-01

    Androgen receptors (ARs) mediate the physiological effects of androgens in vertebrates. In fishes, AR-mediated pathways can be modulated by aquatic contaminants, resulting in the masculinisation of female fish or diminished secondary sex characteristics in males. The Murray-Darling rainbowfish (Melanotaenia fluviatilis) is a small-bodied freshwater teleost used in Australia as a test species for environmental toxicology research. We determined concentration-response profiles for selected agonists and antagonists of rainbowfish ARα and ARβ using transient transactivation assays. For both ARα and ARβ, the order of potency of natural agonists was 11-ketotestosterone (11-KT)>5α-dihydrotestosterone>testosterone>androstenedione. Methyltestosterone was a highly potent agonist of both receptors relative to 11-KT. The relative potency of the veterinary growth-promoting androgen, 17β-trenbolone, varied by more than a factor of 5 between ARα and ARβ. The non-steroidal anti-androgen bicalutamide exhibited high inhibitory potency relative to the structurally related model anti-androgen, flutamide. The inhibitory potency of the agricultural fungicide, vinclozolin, was approximately 1.7-fold relative to flutamide for ARα, but over 20-fold in the case of ARβ. Fluorescent protein tagging of ARs showed that the rainbowfish ARα subtype is constitutively localised to the nucleus, while ARβ is cytoplasmic in the absence of ligand, an observation which agrees with the reported subcellular localisation of AR subtypes from other teleost species. Collectively, these data suggest that M. fluviatilis ARα and ARβ respond differently to environmental AR modulators and that in vivo sensitivity to contaminants may depend on the tissue distribution of the AR subtypes at the time of exposure. PMID:25644213

  10. Role of androgen and vitamin D receptors in endothelial cells from benign and malignant human prostate

    PubMed Central

    Chung, Ivy; Montecinos, Viviana P.; Buttyan, Ralph; Johnson, Candace S.; Smith, Gary J.

    2013-01-01

    Forty years ago, Judah Folkman (Folkman. N Engl J Med 285: 1182–1186, 1971) proposed that tumor growth might be controlled by limiting formation of new blood vessels (angiogenesis) needed to supply a growing tumor with oxygen and nutrients. To this end, numerous “antiangiogenic” agents have been developed and tested for therapeutic efficacy in cancer patients, including prostate cancer (CaP) patients, with limited success. Despite the lack of clinical efficacy of lead anti-angiogenic therapeutics in CaP patients, recent published evidence continues to support the idea that prostate tumor vasculature provides a reasonable target for development of new therapeutics. Particularly relevant to antiangiogenic therapies targeted to the prostate is the observation that specific hormones can affect the survival and vascular function of prostate endothelial cells within normal and malignant prostate tissues. Here, we review the evidence demonstrating that both androgen(s) and vitamin D significantly impact the growth and survival of endothelial cells residing within prostate cancer and that systemic changes in circulating androgen or vitamin D drastically affect blood flow and vascularity of prostate tissue. Furthermore, recent evidence will be discussed about the expression of the receptors for both androgen and vitamin D in prostate endothelial cells that argues for direct effects of these hormone-activated receptors on the biology of endothelial cells. Based on this literature, we propose that prostate tumor vasculature represents an unexplored target for modulation of tumor growth. A better understanding of androgen and vitamin D effects on prostate endothelial cells will support development of more effective angiogenesis-targeting therapeutics for CaP patients. PMID:23548616

  11. The androgen receptor confers protection against diet-induced atherosclerosis, obesity, and dyslipidemia in female mice

    PubMed Central

    Fagman, Johan B.; Wilhelmson, Anna S.; Motta, Benedetta M.; Pirazzi, Carlo; Alexanderson, Camilla; De Gendt, Karel; Verhoeven, Guido; Holmäng, Agneta; Anesten, Fredrik; Jansson, John-Olov; Levin, Malin; Borén, Jan; Ohlsson, Claes; Krettek, Alexandra; Romeo, Stefano; Tivesten, Åsa

    2015-01-01

    Androgens have important cardiometabolic actions in males, but their metabolic role in females is unclear. To determine the physiologic androgen receptor (AR)–dependent actions of androgens on atherogenesis in female mice, we generated female AR-knockout (ARKO) mice on an atherosclerosis-prone apolipoprotein E (apoE)–deficient background. After 8 weeks on a high-fat diet, but not on a normal chow diet, atherosclerosis in aorta was increased in ARKO females (+59% vs. control apoE-deficient mice with intact AR gene). They also displayed increased body weight (+18%), body fat percentage (+62%), and hepatic triglyceride levels, reduced insulin sensitivity, and a marked atherogenic dyslipidemia (serum cholesterol, +52%). Differences in atherosclerosis, body weight, and lipid levels between ARKO and control mice were abolished in mice that were ovariectomized before puberty, consistent with a protective action of ovarian androgens mediated via the AR. Furthermore, the AR agonist dihydrotestosterone reduced atherosclerosis (−41%; thoracic aorta), subcutaneous fat mass (−44%), and cholesterol levels (−35%) in ovariectomized mice, reduced hepatocyte lipid accumulation in hepatoma cells in vitro, and regulated mRNA expression of hepatic genes pivotal for lipid homeostasis. In conclusion, we demonstrate that the AR protects against diet-induced atherosclerosis in female mice and propose that this is mediated by modulation of body composition and lipid metabolism.—Fagman, J. B., Wilhelmson, A. S., Motta, B. M., Pirazzi, C., Alexanderson, C., De Gendt, K., Verhoeven, G., Holmäng, A., Anesten, F., Jansson, J.-O., Levin, M., Borén, J., Ohlsson, C., Krettek, A., Romeo, S., Tivesten, A. The androgen receptor confers protection against diet-induced atherosclerosis, obesity, and dyslipidemia in female mice. PMID:25550469

  12. Enobosarm (GTx-024) Modulates Adult Skeletal Muscle Mass Independently of the Androgen Receptor in the Satellite Cell Lineage.

    PubMed

    Dubois, Vanessa; Simitsidellis, Ioannis; Laurent, Michaël R; Jardi, Ferran; Saunders, Philippa T K; Vanderschueren, Dirk; Claessens, Frank

    2015-12-01

    Androgens increase skeletal muscle mass, but their clinical use is hampered by a lack of tissue selectivity and subsequent side effects. Selective androgen receptor modulators elicit muscle-anabolic effects while only sparingly affecting reproductive tissues. The selective androgen receptor modulator, GTx-024 (enobosarm), is being investigated for cancer cachexia, sarcopenia, and muscle wasting diseases. Here we investigate the role of muscle androgen receptor (AR) in the anabolic effect of GTx-024. In mice lacking AR in the satellite cell lineage (satARKO), the weight of the androgen-sensitive levator ani muscle was lower but was decreased further upon orchidectomy. GTx-024 was as effective as DHT in restoring levator ani weights to sham levels. Expression of the muscle-specific, androgen-responsive genes S-adenosylmethionine decarboxylase and myostatin was decreased by orchidectomy and restored by GTx-024 and DHT in control mice, whereas the expression was low and unaffected by androgen status in satARKO. In contrast, insulin-like growth factor 1Ea expression was not different between satARKO and control muscle, decreased upon castration, and was restored by DHT and GTx-024 in both genotypes. These data indicate that GTx-024 does not selectively modulate AR in the satellite cell lineage and that cells outside this lineage remain androgen responsive in satARKO muscle. Indeed, residual AR-positive cells were present in satARKO muscle, coexpressing the fibroblast-lineage marker vimentin. AR positive, muscle-resident fibroblasts could therefore be involved in the indirect effects of androgens on muscle. In conclusion, both DHT and GTx-024 target AR pathways in the satellite cell lineage, but cells outside this lineage also contribute to the anabolic effects of androgens. PMID:26393303

  13. Identification of androgen receptor antagonists: In vitro investigation and classification methodology for flavonoid.

    PubMed

    Wu, Yang; Doering, Jon A; Ma, Zhiyuan; Tang, Song; Liu, Hongling; Zhang, Xiaowei; Wang, Xiaoxiang; Yu, Hongxia

    2016-09-01

    A tremendous gap exists between the number of potential endocrine disrupting chemicals (EDCs) possibly in the environment and the limitation of traditional regulatory testing. In this study, the anti-androgenic potencies of 21 flavonoids were analyzed in vitro, and another 32 flavonoids from the literature were selected as additional chemicals. Molecular dynamic simulations were employed to obtain four different separation approaches based on the different behaviors of ligands and receptors during the process of interaction. Specifically, ligand-receptor complex which highlighted the discriminating features of ligand escape or retention via "mousetrap" mechanism, hydrogen bonds formed during simulation times, ligand stability and the stability of the helix-12 of the receptor were investigated. Together, a methodology was generated that 87.5% of flavonoids could be discriminated as active versus inactive antagonists, and over 90% inactive antagonists could be filtered out before QSAR study. This methodology could be used as a "proof of concept" to identify inactive anti-androgenic flavonoids, as well could be beneficial for rapid risk assessment and regulation of multiple new chemicals for androgenicity. PMID:27258897

  14. Modulation of androgen receptor protein by culture conditions of human skin fibroblasts.

    PubMed

    Palma, Marcela M; Fernandez, Mireya; Vivanco, Ximena; Pino, Ana M

    2002-10-01

    Cultures of skin fibroblasts show variation of androgen binding with culture conditions; binding variations are usually avoided by using confluent cultures. In this work, we analysed the effect of cell density and mitogenic agents on the level of androgen receptor (AR) of cultured human skin fibroblasts. Results demonstrated that in cultures of human skin fibroblasts, cellular binding of dihydrotestosterone was higher in cells grown at low than at high cell density. The reduction in binding resulted from a decrease in the number of high affinity receptors and not from a change in receptor affinity. Immunocytochemistry for AR showed greater staining intensity in cells grown at low than at high cell density. Additionally, immunoblot analysis demonstrated more AR protein in low cell density cultures. On the other hand, it was observed that cells grown at low cell density showed diminished androgen binding capacity after 24 h of treatment with insulin-like growth factor (IGF-l), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), or granulocyte-colony stimulating factor (G-CSF); this effect of growth factors was not observed in cells grown at high cell density. In conclusion, we found that cell density of cultures and mitogenic agents can regulate AR binding activity in human fibroblasts. While we do not yet know how changes in cell density affect the amount of AR, we conclude that the mechanism could be mediated by activation of the tyrosine kinase pathway, as the effect was reproduced by mitogens. PMID:12270026

  15. Selective activity of deguelin identifies therapeutic targets for androgen receptor-positive breast cancer.

    PubMed

    Robles, Andrew J; Cai, Shengxin; Cichewicz, Robert H; Mooberry, Susan L

    2016-06-01

    Triple-negative breast cancers (TNBC) are aggressive malignancies with no effective targeted therapies. Recent gene expression profiling of these heterogeneous cancers and the classification of cell line models now allows for the identification of compounds with selective activities against molecular subtypes of TNBC. The natural product deguelin was found to have selective activity against MDA-MB-453 and SUM-185PE cell lines, which both model the luminal androgen receptor (LAR) subtype of TNBC. Deguelin potently inhibited proliferation of these cells with GI50 values of 30 and 61 nM, in MDA-MB-453 and SUM-185PE cells, respectively. Deguelin had exceptionally high selectivity, 197 to 566-fold, for these cell lines compared to cell lines representing other TNBC subtypes. Deguelin's mechanisms of action were investigated to determine how it produced these potent and selective effects. Our results show that deguelin has dual activities, inhibiting PI3K/Akt/mTOR signaling, and decreasing androgen receptor levels and nuclear localization. Based on these data, we hypothesized that the combination of the mTOR inhibitor rapamycin and the antiandrogen enzalutamide would have efficacy in LAR models. Rapamycin and enzalutamide showed additive effects in MDA-MB-453 cells, and both drugs had potent antitumor efficacy in a LAR xenograft model. These results suggest that the combination of antiandrogens and mTOR inhibitors might be an effective strategy for the treatment of androgen receptor-expressing TNBC. PMID:27255535

  16. Cloning and expression analysis of androgen receptor gene in chicken embryogenesis.

    PubMed

    Katoh, Hironori; Ogino, Yukiko; Yamada, Gen

    2006-03-01

    We cloned a full-length androgen receptor (AR) cDNA from chicken (Gallus gallus) gonads. The cDNA sequence has an open reading frame of 2109 bp encoding 703 amino acids. The chicken AR (cAR) shares high homology with ARs from other species in its amino acid sequences, in particular DNA binding domain (DBD) and ligand binding domain (LBD). RT-PCR analysis revealed that cAR mRNA is expressed in several embryonic tissues of both sexes, and relatively higher expression was observed in left ovary compared with testis. The immunoreactive signal of AR was co-localized within the ovarian cell nucleus, while such nuclear localization was not detected in those of testis. To get insight on the possible role of androgen-AR signaling during gonadal development, non-steroidal AR antagonist, flutamide, was administrated in ovo. The treatment induced the disorganization of sex cords in ovarian cortex at day 12 of incubation. The effect was restored by testosterone co-treatment, implying the possibility that AR mediated signaling may be involved in ovarian morphogenesis. Furthermore, co-treatment of flutamide with estradiol-17beta (E2) also restored the phenotype, suggesting androgen-AR signaling might activate aromatase expression that is necessary for estrogen synthesis. These findings suggest androgen-AR signaling might contribute to chicken embryonic ovarian development. PMID:16480982

  17. Stromal androgen receptor roles in the development of normal prostate, benign prostate hyperplasia, and prostate cancer.

    PubMed

    Wen, Simeng; Chang, Hong-Chiang; Tian, Jing; Shang, Zhiqun; Niu, Yuanjie; Chang, Chawnshang

    2015-02-01

    The prostate is an androgen-sensitive organ that needs proper androgen/androgen receptor (AR) signals for normal development. The progression of prostate diseases, including benign prostate hyperplasia (BPH) and prostate cancer (PCa), also needs proper androgen/AR signals. Tissue recombination studies report that stromal, but not epithelial, AR plays more critical roles via the mesenchymal-epithelial interactions to influence the early process of prostate development. However, in BPH and PCa, much more attention has been focused on epithelial AR roles. However, accumulating evidence indicates that stromal AR is also irreplaceable and plays critical roles in prostate disease progression. Herein, we summarize the roles of stromal AR in the development of normal prostate, BPH, and PCa, with evidence from the recent results of in vitro cell line studies, tissue recombination experiments, and AR knockout animal models. Current evidence suggests that stromal AR may play positive roles to promote BPH and PCa progression, and targeting stromal AR selectively with AR degradation enhancer, ASC-J9, may allow development of better therapies with fewer adverse effects to battle BPH and PCa. PMID:25432062

  18. Stromal Androgen Receptor Roles in the Development of Normal Prostate, Benign Prostate Hyperplasia, and Prostate Cancer

    PubMed Central

    Wen, Simeng; Chang, Hong-Chiang; Tian, Jing; Shang, Zhiqun; Niu, Yuanjie; Chang, Chawnshang

    2016-01-01

    The prostate is an androgen-sensitive organ that needs proper androgen/androgen receptor (AR) signals for normal development. The progression of prostate diseases, including benign prostate hyperplasia (BPH) and prostate cancer (PCa), also needs proper androgen/AR signals. Tissue recombination studies report that stromal, but not epithelial, AR plays more critical roles via the mesenchymal-epithelial interactions to influence the early process of prostate development. However, in BPH and PCa, much more attention has been focused on epithelial AR roles. However, accumulating evidence indicates that stromal AR is also irreplaceable and plays critical roles in prostate disease progression. Herein, we summarize the roles of stromal AR in the development of normal prostate, BPH, and PCa, with evidence from the recent results of in vitro cell line studies, tissue recombination experiments, and AR knockout animal models. Current evidence suggests that stromal AR may play positive roles to promote BPH and PCa progression, and targeting stromal AR selectively with AR degradation enhancer, ASC-J9, may allow development of better therapies with fewer adverse effects to battle BPH and PCa. PMID:25432062

  19. Association of androgen receptor GGN repeat length polymorphism and male infertility in Khuzestan, Iran

    PubMed Central

    Moghadam, Mohamad; Khatami, Saied Reza; Galehdari, Hamid

    2015-01-01

    Background: Androgens play critical role in secondary sexual and male gonads differentiations such as spermatogenesis, via androgen receptor. The human androgen receptor (AR) encoding gene contains two regions with three nucleotide polymorphic repeats (CAG and GGN) in the first exon. Unlike the CAG repeats, the GGN has been less studied because of technical difficulties, so the functional role of these polymorphic repeats is still unclear. Objective: The goal of this study was to investigate any relationship between GGN repeat length in the first exon of AR gene and idiopathic male infertility in southwest of Iran. Materials and Methods: This is the first study on GGN repeat of AR gene in infertile male in Khuzestan, Iran. We used polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis to categorize GGN repeat lengths in 72 infertile and 72 fertile men. Afterwards we sequenced the PCR products to determine the exact length of GGN repeat in each category. Our samples included 36 azoospermic and 36 oligozoospermic men as cases and 72 fertile men as control group. Results: We found that the numbers of repeats in the cases range from 18 to 25, while in the controls this range is from 20 to 28. The results showed a significant relation between the length of GGN repeat and fertility (p=0.015). The most frequent alleles were alleles with 24 and 25 repeats respectively in case and control groups. On the other hand no significant differences were found between Arab and non-Arab cases by considering GGN repeat lengths (p=0.234). Conclusion: Due to our results, there is a significant association between the presence of allele with 24 repeats and susceptibility to male infertility. Therefore this polymorphism should be considered in future studies to clarify etiology of disorders related to androgen receptor activity. PMID:26221130

  20. Occurrence of androgen and estrogen receptor mRNAs in the harderian gland: a comparative survey.

    PubMed

    Varriale, B

    1996-06-01

    In Rana esculenta the presence of an androgen receptor in both the male and female Harderian gland (HG) has been demonstrated. Hybridization analysis has evidenced a high degree of homology between the rat androgen receptor cDNA and the frog androgen receptor mRNA (fARmRNA). Correspondingly the molecular size of fARmRNA is similar to those described in mammals (9.4 kb). In in vivo experiments testosterone (T) increases the levels of fARmRNA. The use of the antiandrogen alone or in combination with T prevents the increase of fARmRNA. In the control animals a loss of fARmRNA has been observed. In primary cultures of HG cells, the steady-state levels of fARmRNA increase in the cells exposed to T. These results suggest that T exerts an autoinduction on its own receptor, increasing the levels of fARmRNA. In Xenopus laevis the HG shows a sexual dimorphism of the protein pattern. The female shows two major proteins (210 and 180 kDa). Administration of estradiol to the male shifts the protein pattern into the female one. In this respect an estrogen receptor mRNA (ERmRNA) has been found in the female gland and can be induced in the male one. No ARmRNA has been detected in either sexes. A similar sex dimorphism has been found in Gallus domesticus. The female pattern is characterised by a protein fraction of about 210 kDa, the male one by a protein fraction of about 180 kDa. In 4-day-old chicks no sex differences have been found. An ERmRNA is expressed in the female, while no ARmRNA has been detected in both sexes. Neither AR nor ER mRNAs have been detected in the chick HG. Among mammals the HG or the hamster (Mesocricetus auratus) shows an androgen-dependent sex dimorphism. In in vitro experiments T 10(-12) M induces a onefold increase of ARm-RNA with respect to unexposed cells. This effect reaches its maximum (4.4-fold) when cells are exposed to T 10(-8) M. The size of the hamster ARmRNA is similar to that observed in other mammals (9.5 kb). The above results suggest that

  1. Molecular and biochemical effects of a kola nut extract on androgen receptor-mediated pathways.

    PubMed

    Solipuram, Rajasree; Koppula, Sowmya; Hurst, Angela; Harris, Kinesha; Naragoni, Srivatcha; Fontenot, Krystal; Gray, Wesley

    2009-01-01

    The low incidence of prostate cancer in Asians has been attributed to chemopreventative properties of certain chemicals found in their diet. This study characterized the androgenic and chemopreventative properties of the Jamaican bush tea "Bizzy," using androgen receptor positive and negative cell lines. Exposure of prostate cells to Biz-2 resulted in a growth inhibition (GI(50)) of 15 ppm in LNCaP cells and 3.6 ppm in DU145 cells. Biz-2 elicited a 2-fold increase in the mRNA of the anti-apoptotic gene Bcl2, with a 10-fold increase in that of the proapoptotic gene Bax. We observed a 2.4- to 7.5-fold change in apoptotic cells in both cell lines. Biz-2 at 10 ppm elicited a time- and dose-dependent stimulation of both the protein and mRNA levels of several androgen-regulated genes. Biz-2 caused a 36% decrease in PSA secretion and a significant increase in PSA mRNA. The relative binding affinity (IC(50)) of Biz-2 for AR was 2- to 5-fold lower than that of the synthetic androgen R1881. Biz-2 was found to be a specific ligand for the AR in that the natural ligand, DHT, and the anti-androgen, flutamide, displaced Biz-2 bound to AR and inhibited Biz-2-induced transcription and PSA secretion. This study provided evidence that Biz-2 extract possesses the ability to modulate prostate cancer cell biology in an AR-dependent manner. PMID:20107586

  2. Cryptorchidism in Mice with an Androgen Receptor Ablation in Gubernaculum Testis

    PubMed Central

    Kaftanovskaya, Elena M.; Huang, Zaohua; Barbara, Agustin M.; De Gendt, Karel; Verhoeven, Guido; Gorlov, Ivan P.

    2012-01-01

    Androgens play a critical role in the development of the male reproductive system, including the positioning of the gonads. It is not clear, however, which developmental processes are influenced by androgens and what are the target tissues and cells mediating androgen signaling during testicular descent. Using a Cre-loxP approach, we have produced male mice (GU-ARKO) with conditional inactivation of the androgen receptor (Ar) gene in the gubernacular ligament connecting the epididymis to the caudal abdominal wall. The GU-ARKO males had normal testosterone levels but developed cryptorchidism with the testes located in a suprascrotal position. Although initially subfertile, the GU-ARKO males became sterile with age. We have shown that during development, the mutant gubernaculum failed to undergo eversion, a process giving rise to the processus vaginalis, a peritoneal outpouching inside the scrotum. As a result, the cremasteric sac did not form properly, and the testes remained in the low abdominal position. Abnormal development of the cremaster muscles in the GU-ARKO males suggested the participation of androgens in myogenic differentiation; however, males with conditional AR inactivation in the striated or smooth muscle cells had a normal testicular descent. Gene expression analysis showed that AR deficiency in GU-ARKO males led to the misexpression of genes involved in muscle differentiation, cell signaling, and extracellular space remodeling. We therefore conclude that AR signaling in gubernacular cells is required for gubernaculum eversion and outgrowth. The GU-ARKO mice provide a valuable model of isolated cryptorchidism, one of the most common birth defects in newborn boys. PMID:22322597

  3. Molecular cloning, characterization, and expression profiles of androgen receptors in spotted scat (Scatophagus argus).

    PubMed

    Chen, H P; Deng, S P; Dai, M L; Zhu, C H; Li, G L

    2016-01-01

    Androgen plays critical roles in vertebrate reproductive systems via androgen receptors (ARs). In the present study, the full-length spotted scat (Scatophagus argus) androgen receptor (sAR) cDNA sequence was cloned from testis. The sAR cDNA measured 2448 bp in length with an open-reading frame of 2289 bp, encoding 763 amino acids. Amino acid alignment analyses showed that the sARs exhibited highly evolutionary conserved functional domains. Phylogenetically, the sARs clustered within the ARβ common vertebrate group. Real-time polymerase chain reaction (RT-PCR) revealed that sAR expression varied in level and distribution throughout the tissues of both females and males. sAR expression was detected during testicular development by quantitative RT-PCR. The results showed that the highest transcription of sARs was observed in the mid-testicular stage, and remained at a high expression level until the late-testicular stage. In addition, the effects of 17α-methyltestosterone (MT) and estrogen (E2) on the expression of sARs in ovaries were determined using quantitative RT-PCR. sAR expression increased at 12 and 24 h post-MT treatment and decreased with E2 treatment. The present study provides preliminary evidence indicating gonadal plasticity of spotted scat under exogenous steroidal hormone treatments. It also provides a theoretical basis for sex reversal and production of artificial pseudo-males for female monosex breeding. PMID:27173207

  4. Ethnic variation in allele distribution of the androgen receptor (AR) (CAG)n repeat.

    PubMed

    Ackerman, Christine M; Lowe, Lynn P; Lee, Hoon; Hayes, M Geoffrey; Dyer, Alan R; Metzger, Boyd E; Lowe, William L; Urbanek, Margrit

    2012-01-01

    The androgen receptor (AR) is important in reproductive organ development, as well as tissue homeostasis of the pancreas, liver, and skeletal muscle in adulthood. The trinucleotide (CAG)(n) repeat polymorphism in exon 1 of the AR gene is thought to regulate AR activity, with longer alleles conferring reduced receptor activity. Therefore, the evaluation of the allelic distribution of the AR (CAG)(n) repeat in various ethnic groups is crucial in understanding the interindividual variability in AR activity. We evaluated ethnic variation of this AR polymorphism by genotyping individuals from the multiethnic Hyperglycemia and Adverse Pregnancy Outcome study cohort. We genotyped 4421 Caucasian mothers and 3365 offspring of European ancestry; 1494 Thai mothers and 1742 offspring; 1119 Afro-Caribbean mothers and 1142 offspring; and 780 Hispanic mothers and 770 offspring of Mexican ancestry from Bellflower, California. The distributions of (CAG)(n) alleles among all 4 ethnic groups are significantly different (P < .0001). Pairwise tests confirmed significant differences between each pair of ethnicities tested (P < 10(-28)). The relative AR (CAG)(n) repeat length in the different groups was as follows: Afro-Caribbean (shortest repeat lengths and greatest predicted AR activity) < Caucasian < Hispanic < Thai (longest repeat length and lowest predicted AR activity). Significant interethnic differences in the allele frequencies of the AR exon 1 (CAG)(n) polymorphism exist. Our results suggest that there may be potential ethnic differences in androgenic pathway activity and androgen sensitivity. PMID:21597087

  5. Androgen receptor- and PIAS1-regulated gene programs in molecular apocrine breast cancer cells.

    PubMed

    Malinen, Marjo; Toropainen, Sari; Jääskeläinen, Tiina; Sahu, Biswajyoti; Jänne, Olli A; Palvimo, Jorma J

    2015-10-15

    We have analyzed androgen receptor (AR) chromatin binding sites (ARBs) and androgen-regulated transcriptome in estrogen receptor negative molecular apocrine breast cancer cells. These analyses revealed that 42% of ARBs and 39% androgen-regulated transcripts in MDA-MB453 cells have counterparts in VCaP prostate cancer cells. Pathway analyses showed a similar enrichment of molecular and cellular functions among AR targets in both breast and prostate cancer cells, with cellular growth and proliferation being among the most enriched functions. Silencing of the coregulator SUMO ligase PIAS1 in MDA-MB453 cells influenced AR function in a target-selective fashion. An anti-apoptotic effect of the silencing suggests involvement of the PIAS1 in the regulation of cell death and survival pathways. In sum, apocrine breast cancer and prostate cancer cells share a core AR cistrome and target gene signature linked to cancer cell growth, and PIAS1 plays a similar coregulatory role for AR in both cancer cell types. PMID:26219822

  6. Structural analysis of complementary DNA and amino acid sequences of human and rat androgen receptors

    SciTech Connect

    Chang, C.; Kokontis, J.; Liao, S. )

    1988-10-01

    Structural analysis of cDNAs for human and rat androgen receptors (ARs) indicates that the amino-terminal regions of ARs are rich in oligo- and poly(amino acid) motifs as in some homeotic genes. The human AR has a long stretch of repeated glycines, whereas rat AR has a long stretch of glutamines. There is a considerable sequence similarity among ARs and the receptors for glucocorticoids, progestins, and mineralocorticoids within the steroid-binding domains. The cysteine-rich DNA-binding domains are well conserved. Translation of mRNA transcribed from AR cDNAs yielded 94- and 76-kDa proteins and smaller forms that bind to DNA and have high affinity toward androgens. These rat or human ARs were recognized by human autoantibodies to natural Ars. Molecular hybridization studies, using AR cDNAs as probes, indicated that the ventral prostate and other male accessory organs are rich in AR mRNA and that the production of AR mRNA in the target organs may be autoregulated by androgens.

  7. Androgen Receptor Targeted Conjugate for Bimodal Photodynamic Therapy of Prostate Cancer in Vitro.

    PubMed

    Rapozzi, Valentina; Ragno, Daniele; Guerrini, Andrea; Ferroni, Claudia; della Pietra, Emilia; Cesselli, Daniela; Castoria, Gabriella; Di Donato, Marzia; Saracino, Emanuela; Benfenati, Valentina; Varchi, Greta

    2015-08-19

    Prostate cancer (PC) represents the most common type of cancer among males and is the second leading cause of cancer death in men in Western society. Current options for PC therapy remain unsatisfactory, since they often produce uncomfortable long-term side effects, such as impotence (70%) and incontinence (5-20%) even in the first stages of the disease. Light-triggered therapies, such as photodynamic therapy, have the potential to provide important advances in the treatment of localized and partially metastasized prostate cancer. We have designed a novel molecular conjugate (DR2) constituted of a photosensitizer (pheophorbide a, Pba), connected to a nonsteroidal anti-androgen molecule through a small pegylated linker. This study aims at investigating whether DR2 represents a valuable approach for PC treatment based on light-induced production of single oxygen and nitric oxide (NO) in vitro. Besides being able to efficiently bind the androgen receptor (AR), the 2-trifluoromethylnitrobenzene ring on the DR2 backbone is able to release cytotoxic NO under the exclusive control of light, thus augmenting the general photodynamic effect. Although DR2 is similarly internalized in cells expressing different levels of androgen receptor, the AR ligand prevents its efflux through the ABCG2-pump. In vitro phototoxicity experiments demonstrated the ability of DR2 to kill cancer cells more efficiently than Pba, while no dark toxicity was observed. Overall, the presented approach is very promising for further development of AR-photosensitizer conjugates in the multimodal photodynamic treatment of prostate cancer. PMID:26108715

  8. ODM-201: a new-generation androgen receptor inhibitor in castration-resistant prostate cancer.

    PubMed

    Fizazi, Karim; Albiges, Laurence; Loriot, Yohann; Massard, Christophe

    2015-01-01

    Androgen deprivation therapy is the standard of care for patients with advanced hormone-sensitive prostate cancer. Despite an initial response, most patients progress to castration-resistant prostate cancer (CRPC). The realization that CRPC remains driven by androgen receptor (AR) signaling has formed the basis for a new generation of agents targeting the AR axis. Two of these agents, abiraterone acetate and enzalutamide, have been shown to prolong overall survival in patients with CRPC. Several other AR inhibitors are currently in development for the treatment of CRPC. The present article reviews ODM-201, a new-generation AR inhibitor with a unique molecular structure, in the treatment of CRPC. The design of an ongoing Phase III trial (ARAMIS) of ODM-201 in men with non-metastatic CRPC is also discussed, at a disease stage for which there is currently no approved treatment. PMID:26313416

  9. ODM-201: a new-generation androgen receptor inhibitor in castration-resistant prostate cancer

    PubMed Central

    Fizazi, Karim; Albiges, Laurence; Loriot, Yohann; Massard, Christophe

    2015-01-01

    Androgen deprivation therapy is the standard of care for patients with advanced hormone-sensitive prostate cancer. Despite an initial response, most patients progress to castration-resistant prostate cancer (CRPC). The realization that CRPC remains driven by androgen receptor (AR) signaling has formed the basis for a new generation of agents targeting the AR axis. Two of these agents, abiraterone acetate and enzalutamide, have been shown to prolong overall survival in patients with CRPC. Several other AR inhibitors are currently in development for the treatment of CRPC. The present article reviews ODM-201, a new-generation AR inhibitor with a unique molecular structure, in the treatment of CRPC. The design of an ongoing Phase III trial (ARAMIS) of ODM-201 in men with non-metastatic CRPC is also discussed, at a disease stage for which there is currently no approved treatment. PMID:26313416

  10. BAY 1024767 blocks androgen receptor mutants found in castration-resistant prostate cancer patients

    PubMed Central

    Sugawara, Tatsuo; Lejeune, Pascale; Köhr, Silke; Neuhaus, Roland; Faus, Hortensia; Gelato, Kathy A.; Busemann, Matthias; Cleve, Arwed; Lücking, Ulrich; von Nussbaum, Franz; Brands, Michael; Mumberg, Dominik; Jung, Klaus; Stephan, Carsten; Haendler, Bernard

    2016-01-01

    Androgen receptor (AR) mutations arise in patients developing resistance to hormone deprivation therapies. Here we describe BAY 1024767, a thiohydantoin derivative with strong antagonistic activity against nine AR variants with mutations located in the AR ligand-binding domain (LBD), and against wild-type AR. Antagonism was maintained, though reduced, at increased androgen levels. Anti-tumor efficacy was evidenced in vivo in the KuCaP-1 prostate cancer model which bears the W741C bicalutamide resistance mutation and in the syngeneic prostate cancer rat model Dunning R3327-G. The prevalence of six selected AR mutations was determined in plasma DNA originating from 100 resistant patients and found to be at least 12%. Altogether the results show BAY 1024767 to be a strong antagonist for several AR mutants linked to therapy resistance, which opens the door for next-generation compounds that can benefit patients based on their mutation profile. PMID:26760770

  11. BAY 1024767 blocks androgen receptor mutants found in castration-resistant prostate cancer patients.

    PubMed

    Sugawara, Tatsuo; Lejeune, Pascale; Köhr, Silke; Neuhaus, Roland; Faus, Hortensia; Gelato, Kathy A; Busemann, Matthias; Cleve, Arwed; Lücking, Ulrich; von Nussbaum, Franz; Brands, Michael; Mumberg, Dominik; Jung, Klaus; Stephan, Carsten; Haendler, Bernard

    2016-02-01

    Androgen receptor (AR) mutations arise in patients developing resistance to hormone deprivation therapies. Here we describe BAY 1024767, a thiohydantoin derivative with strong antagonistic activity against nine AR variants with mutations located in the AR ligand-binding domain (LBD), and against wild-type AR. Antagonism was maintained, though reduced, at increased androgen levels. Anti-tumor efficacy was evidenced in vivo in the KuCaP-1 prostate cancer model which bears the W741C bicalutamide resistance mutation and in the syngeneic prostate cancer rat model Dunning R3327-G. The prevalence of six selected AR mutations was determined in plasma DNA originating from 100 resistant patients and found to be at least 12%. Altogether the results show BAY 1024767 to be a strong antagonist for several AR mutants linked to therapy resistance, which opens the door for next-generation compounds that can benefit patients based on their mutation profile. PMID:26760770

  12. Protein kinase D1 (PKD1) influences androgen receptor (AR) function in prostate cancer cells

    SciTech Connect

    Mak, Paul; Jaggi, Meena; Chauhan, Subhash C.; Balaji, K.C.

    2008-09-05

    Protein kinase D1 (PKD1), founding member of PKD protein family, is down-regulated in advanced prostate cancer (PCa). We demonstrate that PKD1 and androgen receptor (AR) are present as a protein complex in PCa cells. PKD1 is associated with a transcriptional complex which contains AR and promoter sequence of the Prostate Specific Antigen (PSA) gene. Ectopic expression of wild type PKD1 and the kinase dead mutant PKD1 (K628W) attenuated the ligand-dependent transcriptional activation of AR in prostate cancer cells and yeast cells indicating that PKD1 can affect AR transcription activity, whereas knocking down PKD1 enhanced the ligand-dependent transcriptional activation of AR. Co-expression of kinase dead mutant with AR significantly inhibited androgen-mediated cell proliferation in both LNCaP and DU145 PC cells. Our data demonstrate for the first time that PKD1 can influence AR function in PCa cells.

  13. Cross-talk between androgen receptor/filamin A and TrkA regulates neurite outgrowth in PC12 cells

    PubMed Central

    Di Donato, Marzia; Bilancio, Antonio; D'Amato, Loredana; Claudiani, Pamela; Oliviero, Maria Antonietta; Barone, Maria Vittoria; Auricchio, Alberto; Appella, Ettore; Migliaccio, Antimo; Auricchio, Ferdinando; Castoria, Gabriella

    2015-01-01

    Steroids and growth factors control neuronal development through their receptors under physiological and pathological conditions. We show that PC12 cells harbor endogenous androgen receptor (AR), whose inhibition or silencing strongly interferes with neuritogenesis stimulated by the nonaromatizable synthetic androgen R1881 or NGF. This implies a role for AR not only in androgen signaling, but also in NGF signaling. In turn, a pharmacological TrkA inhibitor interferes with NGF- or androgen-induced neuritogenesis. In addition, androgen or NGF triggers AR association with TrkA, TrkA interaction with PI3-K δ, and downstream activation of PI3-K δ and Rac in PC12 cells. Once associated with AR, filamin A (FlnA) contributes to androgen or NGF neuritogenesis, likely through its interaction with signaling effectors, such as Rac. This study thus identifies a previously unrecognized reciprocal cross-talk between AR and TrkA, which is controlled by β1 integrin. The contribution of FlnA/AR complex and PI3-K δ to neuronal differentiation by androgens and NGF is also novel. This is the first description of AR function in PC12 cells. PMID:26063730

  14. Androgen receptor and miRNA-126* axis controls follicle-stimulating hormone receptor expression in porcine ovarian granulosa cells.

    PubMed

    Du, Xing; Li, Qiqi; Pan, Zengxiang; Li, Qifa

    2016-08-01

    Androgen, which acts via the androgen receptor (AR), plays crucial roles in mammalian ovarian function. Recent studies showed that androgen/AR signaling regulates follicle-stimulating hormone receptor (FSHR) expression in follicles; however, the detailed mechanism underlying this regulation remained unknown. Here, we demonstrate that AR and miR-126* cooperate to inhibit FSHR expression and function in pig follicular granulosa cells (pGCs). In pGCs, overexpression of AR decreased, whereas knockdown increased, FSHR mRNA and protein expression; however, neither manipulation affected FSHR promoter activity. Using a dual-luciferase reporter assay, we found that the FSHR gene is a direct target of miR-126*, which inhibits FSHR expression and increases the rate of AR-induced apoptosis in pGCs. Collectively, our data show for the first time that the AR/miR-126* axis exerts synergetic effects in the regulation of FSHR expression and apoptosis in pGCs. Our findings thus define a novel pathway, AR/miR-126*/FSHR, that regulates mammalian GC functions. PMID:27222597

  15. Androgen receptor expression and morphology of forebrain and neuromuscular systems in male green anoles displaying individual differences in sexual behavior.

    PubMed

    Neal, Jennifer K; Wade, Juli

    2007-08-01

    Investigating individual differences in sexual performance in unmanipulated males is important for understanding natural relationships between behavior and morphology, and the mechanisms regulating them. Among male green anole lizards, some court and copulate frequently (studs) and others do not (duds). To evaluate potential factors underlying differences in the level of these behaviors, morphology and androgen receptor expression in neuromuscular courtship and copulatory structures, as well as in the preoptic area and amygdala, were compared in males displaying varying degrees of sexual function. This study revealed that individual differences in behavior among unmanipulated males, in particular the extension of a throat fan (dewlap) used during courtship, were positively correlated with the size of fibers in the associated muscle and with soma size in the amygdala. The physiological response to testosterone, as indicated by the height of cells in an androgen-sensitive portion of the kidney, was also correlated with male sexual behavior, and predicted it better than plasma androgen levels. Androgen receptor expression was not related to the display of courtship or copulation in any of the tissues examined. The present data indicate that higher levels of male courtship behavior result in (or are the result of) enhanced courtship muscle and amygdala morphology, and that androgen-sensitive tissue in studs may be more responsive to testosterone than duds. However, some mechanism(s) other than androgen receptor expression likely confer this difference in responsiveness. PMID:17531996

  16. Androgen receptor expression and morphology of forebrain and neuromuscular systems in male green anoles displaying individual differences in sexual behavior

    PubMed Central

    Neal, Jennifer K.; Wade, Juli

    2010-01-01

    Investigating individual differences in sexual performance in unmanipulated males is important for understanding natural relationships between behavior and morphology, and the mechanisms regulating them. Among male green anole lizards, some court and copulate frequently (studs) and others do not (duds). To evaluate potential factors underlying differences in the level of these behaviors, morphology and androgen receptor expression in neuromuscular courtship and copulatory structures, as well as in the preoptic area and amygdala, were compared in males displaying varying degrees of sexual function. This study revealed that individual differences in behavior among unmanipulated males, in particular the extension of a throat fan (dewlap) used during courtship, were positively correlated with the size of fibers in the associated muscle and with soma size in the amygdala. The physiological response to testosterone, as indicated by the height of cells in an androgen-sensitive portion of the kidney, was also correlated with male sexual behavior, and predicted it better than plasma androgen levels. Androgen receptor expression was not related to the display of courtship or copulation in any of the tissues examined. The present data indicate that higher levels of male courtship behavior result in (or are the result of) enhanced courtship muscle and amygdala morphology, and that androgen-sensitive tissue in studs may be more responsive to testosterone than duds. However, some mechanism(s) other than androgen receptor expression likely confer this difference in responsiveness. PMID:17531996

  17. Female predominance in meningiomas can not be explained by differences in progesterone, estrogen, or androgen receptor expression.

    PubMed

    Korhonen, Katariina; Salminen, Tiina; Raitanen, Jani; Auvinen, Anssi; Isola, Jorma; Haapasalo, Hannu

    2006-10-01

    The female predominance in meningioma incidence and association between meningioma and breast cancer suggest that growth of meningiomas is hormone-dependent. There are several discrepancies in literature about the proliferative effect of sex hormones on meningiomas. This study aims to evaluate the hormone receptor status of meningiomas and assess its relation to age, sex, histological grade, recurrence, and proliferation activity. The material was based on consecutive patients operated for meningioma at Tampere University Hospital in 1989-1999. The occurrence of progesterone, estrogen and androgen receptor in patients with primary and recurrent meningiomas was studied immunohistochemically by using specific monoclonal antibodies. Hormonal status was determined in 510 tumor samples. 443 samples were from primary meningiomas and 67 from recurrent tumors. Of the samples, 455 were benign (WHO grade I), 49 atypical (grade II), and 6 malignant (grade III). Of the primary tumor samples, 88% were progesterone receptor positive, 40% were positive for estrogen and 39% for androgen receptors. Grade I meningiomas had significantly higher incidence for estrogen and androgen receptors than higher grade meningiomas. Estrogen positive tumor samples had significantly higher proliferation index than estrogen negative samples. No difference in expression of sex hormone receptors was observed by sexes or age group. Estrogen and androgen receptors may have more influence on the pathogenesis of meningiomas than earlier thought. The higher incidence of meningiomas in women can not be explained by differences of sex hormone receptor expression. PMID:16703453

  18. Tissue- and cell-specific functions of the androgen receptor revealed through conditional knockout models in mice.

    PubMed

    De Gendt, Karel; Verhoeven, Guido

    2012-04-16

    This review aims to evaluate the contribution of individual cell-selective knockout models to our current understanding of androgen action. Cre/loxP technology has allowed the generation of cell-selective knockout models targeting the androgen receptor (AR) in distinct putative target cells in a wide variety of organs and tissues including: testis, ovary, accessory sex tissues, muscle, bone, fat, liver, skin and myeloid tissue. In some androgen-regulated processes such as spermatogenesis and folliculogenesis this approach has lead to the identification of a key cellular mediator of androgen action (Sertoli and granulosa cells, respectively). In many target tissues, however, the final response to androgens appears to be more complex. Here, cell-selective knockout technology offers a platform upon which we can begin to unravel the more complex interplay and signaling pathways of androgens. A prototypic example is the analysis of mesenchymal-epithelial interactions in many accessory sex glands. Furthermore, for some actions of testosterone, in which part of the effect is mediated by the active metabolite 17β-estradiol, conditional knockout technology offers a novel strategy to study the relative contribution of AR and estrogen receptor-mediated signaling. The latter approach has already resulted in a better understanding of androgen action in brain and bone. Finally, cell-selective knockout technology has generated valuable models to search for AR-controlled molecular mediators of androgen action, a strategy that has successfully been applied to the study of androgen action in the testis and in the epididymis. Although some conditional knockout models have provided clear answers to physiologic questions, it should be noted that others have pointed to unexpected complexities or technical limitations confounding interpretation of the results. PMID:21871526

  19. An examination of the characteristics, concentration, and distribution of androgen receptor in rat testis during sexual maturation

    SciTech Connect

    Buzek, S.W.

    1989-01-01

    In these studies a nuclear exchange assay was established in rat testis in which exchange after 86 hours at 4{degree}C was greater than 85% complete and receptor was stable. Receptor concentration per DNA measured by exchange declined between 15 and 25 days of age in the rat testis, then increased 4-fold during sexual maturation. Proliferation of germ cells which had low receptor concentration appeared to account for the early decline in testicular receptor concentration, whereas increase in receptor number per Sertoli cell between 25 and 35 days of age contributed to the later increase. Detailed studies showed that other possible explanations for changes in receptor number were not likely. Androgen receptor dynamics in testicular cells showed rapid, specific uptake of ({sup 3}H)-testosterone that was easily blocked by unlabeled testosterone, and medroxyprogesterone acetate, but not as well as by the anti-androgens cyproterone acetate and hydroxyflutamide.

  20. The AhR Ligand, TCDD, Regulates Androgen Receptor Activity Differently in Androgen-Sensitive versus Castration-Resistant Human Prostate Cancer Cells.

    PubMed

    Ghotbaddini, Maryam; Powell, Joann B

    2015-07-01

    The reported biological effects of TCDD include induction of drug metabolizing enzymes, wasting syndrome and tumor promotion. TCDD elicits most of its effects through binding the aryl hydrocarbon receptor (AhR). TCDD induced degradation of AhR has been widely reported and requires ubiquitination of the protein. The rapid depletion of AhR following TCDD activation serves as a mechanism to modulate AhR mediated gene induction. In addition to inducing AhR degradation, TCDD has been reported to induce degradation of hormone receptors. The studies reported here, evaluate the effect of TCDD exposure on androgen receptor (AR) expression and activity in androgen-sensitive LNCaP and castration-resistant C4-2 prostate cancer cells. Our results show that TCDD exposure does not induce AhR or AR degradation in C4-2 cells. However, both AhR and AR are degraded in LNCaP cells following TCDD exposure. In addition, TCDD enhances AR phosphorylation and induces expression of AR responsive genes in LNCaP cells. Our data reveals that TCDD effect on AR expression and activity differs in androgen-sensitive and castration-resistant prostate cancer cell models. PMID:26154658

  1. The AhR Ligand, TCDD, Regulates Androgen Receptor Activity Differently in Androgen-Sensitive versus Castration-Resistant Human Prostate Cancer Cells

    PubMed Central

    Ghotbaddini, Maryam; Powell, Joann B.

    2015-01-01

    The reported biological effects of TCDD include induction of drug metabolizing enzymes, wasting syndrome and tumor promotion. TCDD elicits most of its effects through binding the aryl hydrocarbon receptor (AhR). TCDD induced degradation of AhR has been widely reported and requires ubiquitination of the protein. The rapid depletion of AhR following TCDD activation serves as a mechanism to modulate AhR mediated gene induction. In addition to inducing AhR degradation, TCDD has been reported to induce degradation of hormone receptors. The studies reported here, evaluate the effect of TCDD exposure on androgen receptor (AR) expression and activity in androgen-sensitive LNCaP and castration-resistant C4-2 prostate cancer cells. Our results show that TCDD exposure does not induce AhR or AR degradation in C4-2 cells. However, both AhR and AR are degraded in LNCaP cells following TCDD exposure. In addition, TCDD enhances AR phosphorylation and induces expression of AR responsive genes in LNCaP cells. Our data reveals that TCDD effect on AR expression and activity differs in androgen-sensitive and castration-resistant prostate cancer cell models. PMID:26154658

  2. Adaptive responses of androgen receptor signaling in castration-resistant prostate cancer

    PubMed Central

    2015-01-01

    Prostate Cancer (PCa) is an important age-related disease being the most common cancer malignancy and the second leading cause of cancer mortality in men in Western countries. Initially, PCa progression is androgen receptor (AR)- and androgen-dependent. Eventually advanced PCa reaches the stage of Castration-Resistant Prostate Cancer (CRPC), but remains dependent on AR, which indicates the importance of AR activity also for CRPC. Here, we discuss various pathways that influence the AR activity in CRPC, which indicates an adaptation of the AR signaling in PCa to overcome the treatment of PCa. The adaptation pathways include interferences of the normal regulation of the AR protein level, the expression of AR variants, the crosstalk of the AR with cytokine tyrosine kinases, the Src-Akt-, the MAPK-signaling pathways and AR corepressors. Furthermore, we summarize the current treatment options with regard to the underlying molecular basis of the common adaptation processes of AR signaling that may arise after the treatment with AR antagonists, androgen deprivation therapy (ADT) as well as for CRPC, and point towards novel therapeutic strategies. The understanding of individualized adaptation processes in PCa will lead to individualized treatment options in the future. PMID:26325261

  3. Regulation of androgen receptor splice variant AR3 by PCGEM1

    PubMed Central

    Zhang, Ziqiang; Zhou, Nanjiang; Huang, Jianguo; Ho, Tsui-Ting; Zhu, Zhuxian; Qiu, Zhongmin; Zhou, Xinchun; Bai, Chunxue; Wu, Fangting; Xu, Min; Mo, Yin-Yuan

    2016-01-01

    The androgen receptor (AR) is required for prostate development and is also a major driver of prostate cancer pathogenesis. Thus androgen deprivation therapy (ADT) is the mainstay of treatment for advanced prostate cancer. However, castration resistance due to expression of constitutively active AR splice variants is a significant challenge to prostate cancer therapy; little is known why effectiveness of ADT can only last for a relatively short time. In the present study, we show that PCGEM1 interacts with splicing factors heterogeneous nuclear ribonucleoprotein (hnRNP) A1 and U2AF65, as determined by RNA precipitation and Western blot, suggesting a role for PCGEM1 in alternative splicing. In support of this possibility, PCGEM1 is correlated with AR3, a predominant and clinically important form of AR splice variants in prostate cancer. Moreover, androgen deprivation (AD) induces PCGEM1 and causes its accumulation in nuclear speckles. Finally, we show that the AD-induced PCGEM1 regulates the competition between hnRNP A1 and U2AF65 for AR pre-mRNA. AD promotes PCGEM1 to interact with both hnRNP A1 and U2AF65 with different consequences. While the interaction of PCGEM1 with hnRNP A1 suppresses AR3 by exon skipping, its interaction with U2AF65 promotes AR3 by exonization. Together, we demonstrate an AD-mediated AR3 expression involving PCGEM1 and splicing factors. PMID:26848868

  4. Variable expressivity and mutation databases: The androgen receptor gene mutations database.

    PubMed

    Gottlieb, B; Beitel, L K; Trifiro, M A

    2001-05-01

    For over 50 years genetics has presumed that variations in phenotypic expression have, for the most part, been the result of alterations in genotype. The importance and value of mutation databases has been based on the premise that the same gene or allelic variation in a specific gene that has been proven to determine a specific phenotype, will always produce the same phenotype. However, recent evidence has shown that so called "simple" Mendelian disorders or monogenic traits are often far from simple, exhibiting phenotypic variation (variable expressivity) that cannot be explained solely by a gene or allelic alteration. The AR gene mutations database now lists 25 cases where different degrees of androgen insensitivity are caused by identical mutations in the androgen receptor gene. In five of these cases the phenotypic variability is due to somatic mosaicism, that is, somatic mutations that occur in only certain cells of androgen-sensitive tissue. Recently, a number of other cases of variable expressivity have also been linked to somatic mosaicism. The impact of variable expressivity due to somatic mutations and mosaicism on mutation databases is discussed. In particular, the effect of an organism exhibiting genetic heterogeneity within its tissues, and the possibility of an organism's genotype changing over its lifetime, are considered to have important implications for mutation databases in the future. PMID:11317353

  5. Androgen receptor polyglutamine repeat number: models of selection and disease susceptibility

    PubMed Central

    Ryan, Calen P; Crespi, Bernard J

    2013-01-01

    Variation in polyglutamine repeat number in the androgen receptor (AR CAGn) is negatively correlated with the transcription of androgen-responsive genes and is associated with susceptibility to an extensive list of human disease. Only a small portion of the heritability for many of these diseases is explained by conventional SNP-based genome-wide association studies, and the forces shaping AR CAGn among humans remains largely unexplored. Here, we propose evolutionary models for understanding selection at the AR CAG locus, namely balancing selection, sexual conflict, accumulation-selection, and antagonistic pleiotropy. We evaluate these models by examining AR CAGn-linked susceptibility to eight extensively studied diseases representing the diverse physiological roles of androgens, and consider the costs of these diseases by their frequency and fitness effects. Five diseases could contribute to the distribution of AR CAGn observed among contemporary human populations. With support for disease susceptibilities associated with long and short AR CAGn, balancing selection provides a useful model for studying selection at this locus. Gender-specific differences AR CAGn health effects also support this locus as a candidate for sexual conflict over repeat number. Accompanied by the accumulation of AR CAGn in humans, these models help explain the distribution of repeat number in contemporary human populations. PMID:23467468

  6. Androgen receptor repression of gonadotropin-releasing hormone gene transcription via enhancer 1.

    PubMed

    Brayman, Melissa J; Pepa, Patricia A; Mellon, Pamela L

    2012-11-01

    Gonadotropin-releasing hormone (GnRH) plays a major role in the hypothalamic-pituitary-gonadal (HPG) axis, and synthesis and secretion of GnRH are regulated by gonadal steroid hormones. Disruptions in androgen levels are involved in a number of reproductive defects, including hypogonadotropic hypogonadism and polycystic ovarian syndrome. Androgens down-regulate GnRH mRNA synthesis in vivo and in vitro via an androgen receptor (AR)-dependent mechanism. Methyltrienolone (R1881), a synthetic AR agonist, represses GnRH expression through multiple sites in the proximal promoter. In this study, we show AR also represses GnRH transcription via the major enhancer (GnRH-E1). A multimer of the -1800/-1766 region was repressed by R1881 treatment. Mutation of two bases, -1792 and -1791, resulted in decreased basal activity and a loss of AR-mediated repression. AR bound to the -1796/-1791 sequence in electrophoretic mobility shift assays, indicating a direct interaction with DNA or other transcription factors in this region. We conclude that AR repression of GnRH-E1 acts via multiple AR-responsive regions, including the site at -1792/-1791. PMID:22877652

  7. Identification of Androgen Receptor Splice Variants in the Pten Deficient Murine Prostate Cancer Model.

    PubMed

    Liang, Mengmeng; Adisetiyo, Helty; Li, Xiuqing; Liu, Xiuqing; Liu, Ren; Gill, Parkash; Roy-Burman, Pradip; Jones, Jeremy O; Mulholland, David J

    2015-01-01

    Androgen receptor (AR) variants are associated with resistance to anti androgen therapy both in human prostate cancer cell lines and clinical samples. These observations support the hypothesis that AR isoform accumulation is a consequence of selective therapeutic pressure on the full length AR. The Pten deficient prostate cancer model proceeds with well-defined kinetics including progression to castration resistant prostate cancer (CRPC). While surgical castration and enzalutamide treatments yield an initial therapeutic response, Pten-/-epithelia continue to proliferate yielding locally invasive primary tumor pathology. That most epithelium remains AR positive, but ligand independent, suggests the presence of oncogenic AR variants. To address this hypothesis, we have used a panel of recently described Pten-/- tumor cell lines derived from both from hormone intact (E4, E8) and castrated Pten mutants (cE1, cE2) followed by RACE PCR to identify and characterize three novel truncated, amino terminus containing AR variants (mAR-Va, b, c). Variants appear not only conserved throughout progression but are correlated with nearly complete loss of full length AR (AR-FL) at castrate androgen levels. The overexpression of variants leads to enhanced transcriptional activity of AR while knock down studies show reduced transcriptional output. Collectively, the identification of truncated AR variants in the conditional PTEN deletion model supports a role for maintaining the CRPC phenotype and provides further therapeutic applications of this preclinical model. PMID:26196517

  8. Pituitary Androgen Receptor Signalling Regulates Prolactin but Not Gonadotrophins in the Male Mouse

    PubMed Central

    O’Hara, Laura; Curley, Michael; Tedim Ferreira, Maria; Cruickshanks, Lyndsey; Milne, Laura; Smith, Lee B.

    2015-01-01

    Production of the androgen testosterone is controlled by a negative feedback loop within the hypothalamic-pituitary-gonadal (HPG) axis. Stimulation of testicular Leydig cells by pituitary luteinising hormone (LH) is under the control of hypothalamic gonadotrophin releasing hormone (GnRH), while suppression of LH secretion by the pituitary is controlled by circulating testosterone. Exactly how androgens exert their feedback control of gonadotrophin secretion (and whether this is at the level of the pituitary), as well as the role of AR in other pituitary cell types remains unclear. To investigate these questions, we exploited a transgenic mouse line (Foxg1Cre/+; ARfl/y) which lacks androgen receptor in the pituitary gland. Both circulating testosterone and gonadotrophins are unchanged in adulthood, demonstrating that AR signalling is dispensable in the male mouse pituitary for testosterone-dependent regulation of LH secretion. In contrast, Foxg1Cre/+; ARfl/y males have a significant increase in circulating prolactin, suggesting that, rather than controlling gonadotrophins, AR-signalling in the pituitary acts to suppress aberrant prolactin production in males. PMID:25799562

  9. Enhancer RNAs participate in androgen receptor-driven looping that selectively enhances gene activation.

    PubMed

    Hsieh, Chen-Lin; Fei, Teng; Chen, Yiwen; Li, Tiantian; Gao, Yanfei; Wang, Xiaodong; Sun, Tong; Sweeney, Christopher J; Lee, Gwo-Shu Mary; Chen, Shaoyong; Balk, Steven P; Liu, Xiaole Shirley; Brown, Myles; Kantoff, Philip W

    2014-05-20

    The androgen receptor (AR) is a key factor that regulates the behavior and fate of prostate cancer cells. The AR-regulated network is activated when AR binds enhancer elements and modulates specific enhancer-promoter looping. Kallikrein-related peptidase 3 (KLK3), which codes for prostate-specific antigen (PSA), is a well-known AR-regulated gene and its upstream enhancers produce bidirectional enhancer RNAs (eRNAs), termed KLK3e. Here, we demonstrate that KLK3e facilitates the spatial interaction of the KLK3 enhancer and the KLK2 promoter and enhances long-distance KLK2 transcriptional activation. KLK3e carries the core enhancer element derived from the androgen response element III (ARE III), which is required for the interaction of AR and Mediator 1 (Med1). Furthermore, we show that KLK3e processes RNA-dependent enhancer activity depending on the integrity of core enhancer elements. The transcription of KLK3e was detectable and its expression is significantly correlated with KLK3 (R(2) = 0.6213, P < 5 × 10(-11)) and KLK2 (R(2) = 0.5893, P < 5 × 10(-10)) in human prostate tissues. Interestingly, RNAi silencing of KLK3e resulted in a modest negative effect on prostate cancer cell proliferation. Accordingly, we report that an androgen-induced eRNA scaffolds the AR-associated protein complex that modulates chromosomal architecture and selectively enhances AR-dependent gene expression. PMID:24778216

  10. Effects of testosterone on synaptic plasticity mediated by androgen receptors in male SAMP8 mice.

    PubMed

    Jia, Jian-Xin; Cui, Cheng-Li; Yan, Xu-Sheng; Zhang, Bai-Feng; Song, Wei; Huo, Dong-Sheng; Wang, He; Yang, Zhan-Jun

    2016-01-01

    Synaptic changes are closely associated with cognitive deficits. In addition, testosterone (T) is known to exert regulative effects on synaptic plasticity. T may improve cognitive deficits in Alzheimer's disease (AD) patients, but the underlying mechanisms of androgenic action on cognitive performance remain unclear. The aim of this study was thus to examine the protective mechanism attributed to T on cognitive performance in an AD senescence, accelerated mouse prone 8 (SAMP8) animal model. Using Golgi staining to quantify the dendritic spine density in hippocampal CA1 region, molecular biomarkers of synapse function were analyzed using immunohistochemistry and western blot. T significantly increased the dendritic spine density in hippocampal CA1 region, while flutamide (F) inhibited these T-mediated effects. Immunohistochemistry and western blot analysis showed that the expression levels of brain derived neurotrophic factor (BDNF), postsynaptic density 95 (PSD-95), and p-cyclic-AMP response element binding protein (CREB)/CREB levels were significantly elevated in the T group, but F reduced the T-induced effects in these biomarkers to control levels. There were no significant differences in the expression levels of PSD-95, BDNF, and p-CREB/CREB between C and F. These findings indicate that the effects of T on improvement in synaptic plasticity were mediated via androgen receptor (AR). It is conceivable that new treatments targeted toward preventing synaptic pathology in AD may involve the use of androgen-acting drugs. PMID:27599230

  11. FOXA1 regulates androgen receptor variant activity in models of castrate-resistant prostate cancer

    PubMed Central

    Nakjang, Sirintra; Chaytor, Lewis; Grey, James; Robson, Craig N.; Gaughan, Luke

    2015-01-01

    Retention of androgen receptor (AR) signalling in castrate-resistant prostate cancer (CRPC) highlights the requirement for the development of more effective AR targeting therapies. A key mechanism of resistance to anti-androgens is through expression of constitutively active AR variants (AR-Vs) that are refractory to next-generation therapies, including Enzalutamide and Abiraterone. By maintaining an androgenic gene signature, AR-Vs drive tumour survival and progression in castrate conditions. Critically, however, our understanding of the mechanics of AR-V-driven transcription is limited, particularly with respect to dependency on pioneer factor function. Here we show that depletion of FOXA1 in the CWR22Rv1 CRPC cell line abrogates the oncogenic potential of AR-Vs. Gene expression profiling reveals that approximately 41% of the AR-V transcriptome requires FOXA1 and that depletion of FOXA1 attenuates AR-V binding at a sub-set of analysed co-regulated genes. Interestingly, AR-V levels are elevated in cells depleted of FOXA1 as a consequence of attenuated negative feedback on the AR gene, but is insufficient to maintain cell growth as evidenced by marked anti-proliferative effects in FOXA1 knockdown cells. In all, our data suggests that AR-Vs are dependent on FOXA1 for sustaining a pro-proliferative gene signature and agents targeting FOXA1 may represent novel therapeutic options for CRPC patients. PMID:26336819

  12. Seasonal expression of androgen receptor in scented gland of muskrat (Ondatra zibethicus).

    PubMed

    Lu, Lu; Liu, Shuqiang; Li, Qinglin; Huang, Shiyang; Bao, Lihong; Sheng, Xia; Han, Yingying; Watanabe, Gen; Taya, Kazuyoshi; Weng, Qiang

    2014-08-01

    Muskrat is a seasonal breeder, males of which secret musk from paired perineal scented glands found beneath the skin at the ventral base of the tail for attracting female during the breeding season. The aim of this study was to investigate the seasonal changes of expression of androgen receptor (AR) in the scented gland of muskrat during the breeding and nonbreeding seasons. Histologically, glandular cells, interstitial cells and excretory tubules were identified in scented glands in both seasons, whereas epithelial cells were sparse in the nonbreeding season. AR was observed in glandular cells of scented glands during the breeding and nonbreeding seasons with stronger immunostaining during the breeding season compared to the nonbreeding season. Consistent with the immunohistochemical results, AR protein level was higher in the scented glands of the breeding season, and then decreased to a relatively low level in the nonbreeding season. The mean mRNA level of Ar was significantly higher in the breeding season than in the nonbreeding season. In addition, plasma gonadotropins and testosterone concentrations were remarkably higher in the breeding season than those in the nonbreeding season. These results suggested that muskrat scented gland was the direct target organ of androgen, and stronger expression of AR in scented glands during the breeding season suggested that androgens may directly influence scented glandular function of the muskrats and also courtship behavior as we inferred. PMID:24818970

  13. Androgen receptor polyglutamine repeat number: models of selection and disease susceptibility.

    PubMed

    Ryan, Calen P; Crespi, Bernard J

    2013-02-01

    Variation in polyglutamine repeat number in the androgen receptor (AR CAGn) is negatively correlated with the transcription of androgen-responsive genes and is associated with susceptibility to an extensive list of human disease. Only a small portion of the heritability for many of these diseases is explained by conventional SNP-based genome-wide association studies, and the forces shaping AR CAGn among humans remains largely unexplored. Here, we propose evolutionary models for understanding selection at the AR CAG locus, namely balancing selection, sexual conflict, accumulation-selection, and antagonistic pleiotropy. We evaluate these models by examining AR CAGn-linked susceptibility to eight extensively studied diseases representing the diverse physiological roles of androgens, and consider the costs of these diseases by their frequency and fitness effects. Five diseases could contribute to the distribution of AR CAGn observed among contemporary human populations. With support for disease susceptibilities associated with long and short AR CAGn, balancing selection provides a useful model for studying selection at this locus. Gender-specific differences AR CAGn health effects also support this locus as a candidate for sexual conflict over repeat number. Accompanied by the accumulation of AR CAGn in humans, these models help explain the distribution of repeat number in contemporary human populations. PMID:23467468

  14. Androgen receptor-mediated regulation of adrenocortical activity in the sand rat, Psammomys obesus.

    PubMed

    Benmouloud, Abdelouafi; Amirat, Zaina; Khammar, Farida; Patchev, Alexandre V; Exbrayat, Jean M; Almeida, Osborne F X

    2014-12-01

    The wild sand rat, Psammomys obesus, displays seasonal variations in adrenocortical activity that parallel those of testicular activity, indicating functional cross-talk between the hypothalamo-pituitary-adrenal and hypothalamo-pituitary-gonadal axes. In the present study, we examined androgen receptor (AR)-mediated actions of testicular steroids in the regulation of adrenocortical function in the sand rat. Specifically, we examined the expression of AR in the adrenal cortex, as well as adrenal apoptosis in male sand rats that had been surgically castrated or castrated and supplemented with testosterone; biochemical indices of adrenocortical function and hormone profiles were also measured. Orchiectomy was followed by an increase in adrenocorticotropic hormone secretion from the anterior pituitary and subsequently, increased adrenocortical activity; the latter was evidenced by orchiectomy-induced increases in the adrenal content of cholesterol and lipids as well as adrenal hypertrophy (seen as an elevation of the RNA/DNA ratio). Further, androgen deprivation respectively up- and downregulated the incidence of apoptosis within the glucocorticoid-producing zona fasciculata and sex steroid-producing zona reticularis. Interestingly, orchiectomy resulted in increased expression of AR in the zona fasciculata. All of the orchiectomy-induced cellular and biochemical responses were reversible after testosterone substitution therapy. Together, these data suggest that adrenocortical activity in the sand rat is seasonally modulated by testicular androgens that act through AR located in the adrenal cortex itself. PMID:25179180

  15. Status-appropriate singing behavior, testosterone and androgen receptor immunolabeling in male European starlings (Sturnus vulgaris).

    PubMed

    Cordes, M A; Stevenson, S A; Riters, L V

    2014-04-01

    Vocalizations convey information about an individual's motivational, internal, and social status. As circumstances change, individuals respond by adjusting vocal behavior accordingly. In European starlings, a male that acquires a nest site socially dominates other males and dramatically increases courtship song. Although circulating testosterone is associated with social status and vocal production it is possible that steroid receptors fine-tune status-appropriate changes in behavior. Here we explored a possible role for androgen receptors. Male starlings that acquired nest sites produced high rates of courtship song. For a subset of males this occurred even in the absence of elevated circulating testosterone. Immunolabeling for androgen receptors (ARir) was highest in the medial preoptic nucleus (POM) in males with both a nest site and elevated testosterone. For HVC, ARir was higher in dominant males with high testosterone (males that sang longer songs) than dominant males with low testosterone (males that sang shorter songs). ARir in the dorsal medial portion of the nucleus intercollicularis (DM) was elevated in males with high testosterone irrespective of dominance status. Song bout length related positively to ARir in POM, HVC and DM, and testosterone concentrations related positively to ARir in POM and DM. Results suggest that the role of testosterone in vocal behavior differs across brain regions and support the hypothesis that testosterone in POM underlies motivation, testosterone in HVC relates to song quality, and testosterone in DM stimulates vocalizations. Our data also suggest that singing may influence AR independent of testosterone and that alternative androgen-independent pathways regulate status-appropriate singing behavior. PMID:24594286

  16. Status-appropriate singing behavior, testosterone and androgen receptor immunolabeling in male European starlings (Sturnus vulgaris)

    PubMed Central

    Cordes, M.A.; Stevenson, S.A.; Riters, L.V.

    2014-01-01

    Vocalizations convey information about an individual’s motivational, internal, and social status. As circumstances change, individuals respond by adjusting vocal behavior accordingly. In European starlings, a male that acquires a nest site socially dominates other males and dramatically increases courtship song. Although circulating testosterone is associated with social status and vocal production it is possible that steroid receptors fine-tune status-appropriate changes in behavior. Here we explored a possible role for androgen receptors. Male starlings that acquired nest sites produced high rates of courtship song. For a subset of males this occurred even in the absence of elevated circulating testosterone. Immunolabeling for androgen receptors (ARir) was highest in the medial preoptic nucleus (POM) in males with both a nest site and elevated testosterone. For HVC, ARir was higher in dominant males with high testosterone (males that sang longer songs) than dominant males with low testosterone (males that sang shorter songs). ARir in the dorsal medial portion of the nucleus intercollicularis (DM) was elevated in males with high testosterone irrespective of dominance status. Song bout length related positively to ARir in POM, HVC and DM, and testosterone concentrations related positively to ARir in POM and DM. Results suggest the role of testosterone in vocal behavior differs across brain regions and support the hypothesis that testosterone in POM underlies motivation, testosterone in HVC relates to song quality, and testosterone in DM stimulates vocalizations. Our data also suggest that singing may influence AR independent of testosterone and that alternative androgen-independent pathways regulate status-appropriate singing behavior. PMID:24594286

  17. Drug-Discovery Pipeline for Novel Inhibitors of the Androgen Receptor.

    PubMed

    Dalal, Kush; Munuganti, Ravi; Morin, Hélène; Lallous, Nada; Rennie, Paul S; Cherkasov, Artem

    2016-01-01

    The androgen receptor (AR) is an important regulator of genes responsible for the development and recurrence of prostate cancer. Current therapies for this disease rely on small-molecule inhibitors that block the transcriptional activity of the AR. Recently, major advances in the development of novel AR inhibitors resulted from X-ray crystallographic information on the receptor and utilization of in silico drug design synergized with rigorous experimental testing.Herein, we describe a drug-discovery pipeline for in silico screening for small molecules that target an allosteric region on the AR termed the binding-function 3 (BF3) site. Following the identification of potential candidates, the compounds are tested in cell culture and biochemical assays for their ability to interact with and inhibit the AR. The described pipeline is readily accessible and could be applied in drug design efforts toward any surface-exposed region on the AR or other related steroid nuclear receptor. PMID:27246333

  18. Neural Androgen Receptor Deletion Impairs the Temporal Processing of Objects and Hippocampal CA1-Dependent Mechanisms.

    PubMed

    Picot, Marie; Billard, Jean-Marie; Dombret, Carlos; Albac, Christelle; Karameh, Nida; Daumas, Stéphanie; Hardin-Pouzet, Hélène; Mhaouty-Kodja, Sakina

    2016-01-01

    We studied the role of testosterone, mediated by the androgen receptor (AR), in modulating temporal order memory for visual objects. For this purpose, we used male mice lacking AR specifically in the nervous system. Control and mutant males were gonadectomized at adulthood and supplemented with equivalent amounts of testosterone in order to normalize their hormonal levels. We found that neural AR deletion selectively impaired the processing of temporal information for visual objects, without affecting classical object recognition or anxiety-like behavior and circulating corticosterone levels, which remained similar to those in control males. Thus, mutant males were unable to discriminate between the most recently seen object and previously seen objects, whereas their control littermates showed more interest in exploring previously seen objects. Because the hippocampal CA1 area has been associated with temporal memory for visual objects, we investigated whether neural AR deletion altered the functionality of this region. Electrophysiological analysis showed that neural AR deletion affected basal glutamate synaptic transmission and decreased the magnitude of N-methyl-D-aspartate receptor (NMDAR) activation and high-frequency stimulation-induced long-term potentiation. The impairment of NMDAR function was not due to changes in protein levels of receptor. These results provide the first evidence for the modulation of temporal processing of information for visual objects by androgens, via AR activation, possibly through regulation of NMDAR signaling in the CA1 area in male mice. PMID:26849367

  19. Effects of alcohol feeding on androgen receptors in the rat pituitary gland

    SciTech Connect

    Chung, K.W.

    1987-10-26

    Specific binding of testosterone-1..beta..,2..beta..-/sup 3/H by cytosol from anterior pituitary gland of ethanol-fed, isocaloric control, and castrated control and ethanol-fed rats with or without testosterone treatment has been investigated by charcoal assay. The number of androgen binding sites was significantly reduced in alcohol-fed rats when compared to the isocaloric control value, with no significant change in Kd. Castration significantly increased the number of receptor sites in control rats and when castrated control animals were treated with testosterone the binding sites were decreased to the intact control level. In contrast, castration or testosterone given to castrated alcohol-fed rats did not alter alcohol-induced reduction of the receptor sites. The binding affinity (Kd) is identical in all groups. The concentration of serum luteinizing hormone (LH) was significantly lower in alcohol-fed rats when compared to that of normal controls. An increased serum LH level with a decreased testosterone level was noted in castrated control rats. However, castration of alcohol-fed rats had little or no effects on the concentrations of LH and testosterone. Administration of testosterone suppressed castration-induced high LH in control rats but alcohol induced reduction of LH level was not altered by this treatment. These findings indicate that alcohol exerts a suppressive effect on the content of androgen receptors and secretory functions of gonadotropins in the pituitary gland. 23 references, 1 figure, 1 table.

  20. Identification of the functional domains of ANT-1, a novel coactivator of the androgen receptor

    SciTech Connect

    Fan Shuli; Goto, Kiminobu; Chen Guangchun; Morinaga, Hidetaka; Nomura, Masatoshi; Okabe, Taijiro; Nawata, Hajime; Yanase, Toshihiko . E-mail: yanase@intmed3.med.kyushu-u.ac.jp

    2006-03-03

    Previously, we identified a transcriptional coactivator for the activation function-1 (AF-1) domain of the human androgen receptor (AR) and designated it androgen receptor N-terminal domain transactivating protein-1 (ANT-1). This coactivator, which contains multiple tetratricopeptide repeat (TPR) motifs from amino acid (aa) 294, is identical to a component of U5 small nuclear ribonucleoprotein particles and binds specifically to the AR or glucocorticoid receptor. Here, we identified four distinct functional domains. The AR-AF-1-binding domain, which bound to either aa 180-360 or 360-532 in AR-AF-1, clearly overlapped with TAU-1 and TAU-5. This domain and the subnuclear speckle formation domain in ANT-1 were assigned within the TPR motifs, while the transactivating and nuclear localization signal domains resided within the N-terminal sequence. The existence of these functional domains may further support the idea that ANT-1 can function as an AR-AF-1-specific coactivator while mediating a transcription-splicing coupling.

  1. Neural Androgen Receptor Deletion Impairs the Temporal Processing of Objects and Hippocampal CA1-Dependent Mechanisms

    PubMed Central

    Dombret, Carlos; Albac, Christelle; Karameh, Nida; Daumas, Stéphanie; Hardin-Pouzet, Hélène; Mhaouty-Kodja, Sakina

    2016-01-01

    We studied the role of testosterone, mediated by the androgen receptor (AR), in modulating temporal order memory for visual objects. For this purpose, we used male mice lacking AR specifically in the nervous system. Control and mutant males were gonadectomized at adulthood and supplemented with equivalent amounts of testosterone in order to normalize their hormonal levels. We found that neural AR deletion selectively impaired the processing of temporal information for visual objects, without affecting classical object recognition or anxiety-like behavior and circulating corticosterone levels, which remained similar to those in control males. Thus, mutant males were unable to discriminate between the most recently seen object and previously seen objects, whereas their control littermates showed more interest in exploring previously seen objects. Because the hippocampal CA1 area has been associated with temporal memory for visual objects, we investigated whether neural AR deletion altered the functionality of this region. Electrophysiological analysis showed that neural AR deletion affected basal glutamate synaptic transmission and decreased the magnitude of N-methyl-D-aspartate receptor (NMDAR) activation and high-frequency stimulation-induced long-term potentiation. The impairment of NMDAR function was not due to changes in protein levels of receptor. These results provide the first evidence for the modulation of temporal processing of information for visual objects by androgens, via AR activation, possibly through regulation of NMDAR signaling in the CA1 area in male mice. PMID:26849367

  2. Androgen-androgen receptor system improves chronic inflammatory conditions by suppressing monocyte chemoattractant protein-1 gene expression in adipocytes via transcriptional regulation.

    PubMed

    Morooka, Nobukatsu; Ueguri, Kei; Yee, Karen Kar Lye; Yanase, Toshihiko; Sato, Takashi

    2016-09-01

    Age-related decreases in sex hormones are closely related to chronic inflammation in obesity and metabolic diseases. Particularly, the molecular basis of androgen activity in regulating inflammation and controlling metabolism remains largely unknown. Obese adipocytes secrete monocyte chemoattractant protein-1 (MCP-1), a key chemokine that promotes the infiltration of monocytes/macrophages into adipose tissue, thereby leading to metabolic disorders. Here, we studied the role of androgen-androgen receptor (AR) action in regulating MCP-1 expression in adipose tissue. We observed the induction of Mcp-1 expression in 3T3-L1 adipocytes co-cultured with RAW264.7 macrophages. Additionally, Mcp-1 expression was upregulated by culturing in conditioned medium derived from inflammatory macrophages (M1-Mφ) containing tumor necrosis factor-alpha (TNF-α). We found that sex hormones downregulated TNF-α-induced Mcp-1 and interleukin (Il)-6 expression in 3T3-L1 adipocytes. Furthermore, luciferase-reporter analysis indicated that MCP-1 promoter activity was predominantly suppressed by dihydrotestosterone (DHT)-AR interactions through functional canonical nuclear factor-kappa B (NF-κB) sites, whereas non-canonical NF-κB site containing important flanking sequences exhibited minor contributions to DHT-AR transcriptional repression. These findings suggested that androgen-AR suppressed obesity-induced chronic inflammation in adipose tissue. PMID:27392713

  3. The Androgen Receptor Bridges Stem Cell-Associated Signaling Nodes in Prostate Stem Cells

    PubMed Central

    Davies, Alastair H.; Zoubeidi, Amina

    2016-01-01

    The therapeutic potential of stem cells relies on dissecting the complex signaling networks that are thought to regulate their pluripotency and self-renewal. Until recently, attention has focused almost exclusively on a small set of “core” transcription factors for maintaining the stem cell state. It is now clear that stem cell regulatory networks are far more complex. In this review, we examine the role of the androgen receptor (AR) in coordinating interactions between signaling nodes that govern the balance of cell fate decisions in prostate stem cells. PMID:26880966

  4. Synthesis and biological evaluation of second-generation tropanol-based androgen receptor modulators.

    PubMed

    Sundén, Henrik; Holland, Mareike C; Poutiainen, Pekka K; Jääskeläinen, Tiina; Pulkkinen, Juha T; Palvimo, Jorma J; Olsson, Roger

    2015-02-12

    To circumvent antiandrogen resistance in prostate cancer, antiandrogens effective for both the androgen receptor (AR) and AR mutants are required. The AR antagonists in this study originate from previous findings, which showed that subtle differences in substitution pattern lead to a conformational change that alters the ligand activity, rendering an agonist to an antagonist. We have identified small yet potent tropanol-based ligands possessing significant antiandrogenic activity with both wild-type AR and the two most common AR ligand binding domain (LBD) mutants. PMID:25646649

  5. Targeting Androgen Receptor/Src Complex Impairs the Aggressive Phenotype of Human Fibrosarcoma Cells

    PubMed Central

    Di Donato, Marzia; Hayashi, Ryo; Arra, Claudio; Appella, Ettore; Auricchio, Ferdinando; Migliaccio, Antimo

    2013-01-01

    Background Hormones and growth factors influence the proliferation and invasiveness of human mesenchymal tumors. The highly aggressive human fibrosarcoma HT1080 cell line harbors classical androgen receptor (AR) that responds to androgens triggering cell migration in the absence of significant mitogenesis. As occurs in many human cancer cells, HT1080 cells also express epidermal growth factor receptor (EGFR). Experimental Findings: We report that the pure anti-androgen Casodex inhibits the growth of HT1080 cell xenografts in immune-depressed mice, revealing a novel role of AR in fibrosarcoma progression. In HT1080 cultured cells EGF, but not androgens, robustly increases DNA synthesis. Casodex abolishes the EGF mitogenic effect, implying a crosstalk between EGFR and AR. The mechanism underlying this crosstalk has been analyzed using an AR-derived small peptide, S1, which prevents AR/Src tyrosine kinase association and androgen-dependent Src activation. Present findings show that in HT1080 cells EGF induces AR/Src Association, and the S1 peptide abolishes both the assembly of this complex and Src activation. The S1 peptide inhibits EGF-stimulated DNA synthesis, cell matrix metalloproteinase-9 (MMP-9) secretion and invasiveness of HT1080 cells. Both Casodex and S1 peptide also prevent DNA synthesis and migration triggered by EGF in various human cancer-derived cells (prostate, breast, colon and pancreas) that express AR. Conclusion This study shows that targeting the AR domain involved in AR/Src association impairs EGF signaling in human fibrosarcoma HT1080 cells. The EGF-elicited processes inhibited by the peptide (DNA synthesis, MMP-9 secretion and invasiveness) cooperate in increasing the aggressive phenotype of HT1080 cells. Therefore, AR represents a new potential therapeutic target in human fibrosarcoma, as supported by Casodex inhibition of HT1080 cell xenografts. The extension of these findings in various human cancer-derived cell lines highlights the

  6. Nonmyocytic androgen receptor regulates the sexually dimorphic development of the embryonic bulbocavernosus muscle.

    PubMed

    Ipulan, Lerrie Ann; Suzuki, Kentaro; Sakamoto, Yuki; Murashima, Aki; Imai, Yuuki; Omori, Akiko; Nakagata, Naomi; Nishinakamura, Ryuichi; Valasek, Petr; Yamada, Gen

    2014-07-01

    The bulbocavernosus (BC) is a sexually dimorphic muscle observed only in males. Androgen receptor knockout mouse studies show the loss of BC formation. This suggests that androgen signaling plays a vital role in its development. Androgen has been known to induce muscle hypertrophy through satellite cell activation and myonuclei accretion during muscle regeneration and growth. Whether the same mechanism is present during embryonic development is not yet elucidated. To identify the mechanism of sexual dimorphism during BC development, the timing of morphological differences was first established. It was revealed that the BC was morphologically different between male and female mice at embryonic day (E) 16.5. Differences in the myogenic process were detected at E15.5. The male BC possesses a higher number of proliferating undifferentiated myoblasts. To identify the role of androgen signaling in this process, muscle-specific androgen receptor (AR) mutation was introduced, which resulted in no observable phenotypes. Hence, the expression of AR in the BC was examined and found that the AR did not colocalize with any muscle markers such as Myogenic differentiation 1, Myogenin, and paired box transcription factor 7. It was revealed that the mesenchyme surrounding the BC expressed AR and the BC started to express AR at E15.5. AR mutation on the nonmyocytic cells using spalt-like transcription factor 1 (Sall1) Cre driver mouse was performed, which resulted in defective BC formation. It was revealed that the number of proliferating undifferentiated myoblasts was reduced in the Sall1 Cre:AR(L-/Y) mutant embryos, and the adult mutants were devoid of BC. The transition of myoblasts from proliferation to differentiation is mediated by cyclin-dependent kinase inhibitors. An increased expression of p21 was observed in the BC myoblast of the Sall1 Cre:AR(L-/Y) mutant and wild-type female. Altogether this study suggests that the nonmyocytic AR may paracrinely regulate the

  7. Muscle-specific androgen receptor deletion shows limited actions in myoblasts but not in myofibers in different muscles in vivo.

    PubMed

    Rana, Kesha; Chiu, Maria W S; Russell, Patricia K; Skinner, Jarrod P; Lee, Nicole K L; Fam, Barbara C; Zajac, Jeffrey D; MacLean, Helen E

    2016-08-01

    The aim of this study was to investigate the direct muscle cell-mediated actions of androgens by comparing two different mouse lines. The cre-loxP system was used to delete the DNA-binding activity of the androgen receptor (AR) in mature myofibers (MCK mAR(ΔZF2)) in one model and the DNA-binding activity of the AR in both proliferating myoblasts and myofibers (α-actin mAR(ΔZF2)) in another model. We found that hind-limb muscle mass was normal in MCK mAR(ΔZF2) mice and that relative mass of only some hind-limb muscles was reduced in α-actin mAR(ΔZF2) mice. This suggests that myoblasts and myofibers are not the major cellular targets mediating the anabolic actions of androgens on male muscle during growth and development. Levator ani muscle mass was decreased in both mouse lines, demonstrating that there is a myofiber-specific effect in this unique androgen-dependent muscle. We found that the pattern of expression of genes including c-myc, Fzd4 and Igf2 is associated with androgen-dependent changes in muscle mass; therefore, these genes are likely to be mediators of anabolic actions of androgens. Further research is required to identify the major targets of androgen actions in muscle, which are likely to include indirect actions via other tissues. PMID:27402875

  8. Choline Kinase Alpha as an Androgen Receptor Chaperone and Prostate Cancer Therapeutic Target

    PubMed Central

    Asim, Mohammad; Massie, Charles E.; Orafidiya, Folake; Pértega-Gomes, Nelma; Warren, Anne Y.; Esmaeili, Mohsen; Selth, Luke A.; Zecchini, Heather I.; Luko, Katarina; Qureshi, Arham; Baridi, Ajoeb; Menon, Suraj; Madhu, Basetti; Escriu, Carlos; Lyons, Scott; Vowler, Sarah L.; Zecchini, Vincent R.; Shaw, Greg; Hessenkemper, Wiebke; Russell, Roslin; Mohammed, Hisham; Stefanos, Niki; Lynch, Andy G.; Grigorenko, Elena; D’Santos, Clive; Taylor, Chris; Lamb, Alastair; Sriranjan, Rouchelle; Yang, Jiali; Stark, Rory; Dehm, Scott M.; Rennie, Paul S.; Carroll, Jason S.; Griffiths, John R.; Tavaré, Simon; Mills, Ian G.; McEwan, Iain J.; Baniahmad, Aria; Tilley, Wayne D.; Neal, David E.

    2016-01-01

    Background: The androgen receptor (AR) is a major drug target in prostate cancer (PCa). We profiled the AR-regulated kinome to identify clinically relevant and druggable effectors of AR signaling. Methods: Using genome-wide approaches, we interrogated all AR regulated kinases. Among these, choline kinase alpha (CHKA) expression was evaluated in benign (n = 195), prostatic intraepithelial neoplasia (PIN) (n = 153) and prostate cancer (PCa) lesions (n = 359). We interrogated how CHKA regulates AR signaling using biochemical assays and investigated androgen regulation of CHKA expression in men with PCa, both untreated (n = 20) and treated with an androgen biosynthesis inhibitor degarelix (n = 27). We studied the effect of CHKA inhibition on the PCa transcriptome using RNA sequencing and tested the effect of CHKA inhibition on cell growth, clonogenic survival and invasion. Tumor xenografts (n = 6 per group) were generated in mice using genetically engineered prostate cancer cells with inducible CHKA knockdown. Data were analyzed with χ2 tests, Cox regression analysis, and Kaplan-Meier methods. All statistical tests were two-sided. Results: CHKA expression was shown to be androgen regulated in cell lines, xenografts, and human tissue (log fold change from 6.75 to 6.59, P = .002) and was positively associated with tumor stage. CHKA binds directly to the ligand-binding domain (LBD) of AR, enhancing its stability. As such, CHKA is the first kinase identified as an AR chaperone. Inhibition of CHKA repressed the AR transcriptional program including pathways enriched for regulation of protein folding, decreased AR protein levels, and inhibited the growth of PCa cell lines, human PCa explants, and tumor xenografts. Conclusions: CHKA can act as an AR chaperone, providing, to our knowledge, the first evidence for kinases as molecular chaperones, making CHKA both a marker of tumor progression and a potential therapeutic target for PCa. PMID:26657335

  9. RNA Editing of Androgen Receptor Gene Transcripts in Prostate Cancer Cells*S⃞

    PubMed Central

    Martinez, Harryl D.; Jasavala, Rohini J.; Hinkson, Izumi; Fitzgerald, Latricia D.; Trimmer, James S.; Kung, Hsing-Jien; Wright, Michael E.

    2008-01-01

    Reactivation of the androgen receptor (AR) signaling pathway represents a critical step in the growth and survival of androgen-independent (AI) prostate cancer (CaP). In this study we show the DU145 and PC3 AI human CaP cell lines respond to androgens and require AR expression for optimal proliferation in vitro. Interestingly, AR gene transcripts in DU145 and PC3 cells harbored a large number of single base pair nucleotide transitions that resulted in missense mutations in selected AR codons. The most notable lesion detected in AR gene transcripts included the oncogenic codon 877T→A gain-of-function mutation. Surprisingly, AR gene transcript nucleotide transitions were not genome-encoded substitutions, but instead the mutations co-localized to putative A-to-I, U-to-C, C-to-U, and G-to-A RNA editing sites, suggesting the lesions were mediated through RNA editing mechanisms. Higher levels of mRNA encoding the A-to-I RNA editing enzymes ADAR1 and ADARB1 were observed in DU145 and PC3 cells relative to the androgen-responsive LNCaP and 22Rv1 human CaP cell lines, which correlated with higher levels of AR gene transcript A-to-I editing detected in DU145 and PC3 cells. Our results suggest that AR gene transcripts are targeted by different RNA editing enzymes in DU145 and PC3 cells. Thus RNA editing of AR gene transcripts may contribute to the etiology of hormone-refractory phenotypes in advanced stage AI CaP. PMID:18708348

  10. Peripheral androgen receptors sustain the acrobatics and fine motor skill of elaborate male courtship.

    PubMed

    Fuxjager, Matthew J; Longpre, Kristy M; Chew, Jennifer G; Fusani, Leonida; Schlinger, Barney A

    2013-09-01

    Androgenic hormones regulate many aspects of animal social behavior, including the elaborate display routines on which many species rely for advertisement and competition. One way that this might occur is through peripheral effects of androgens, particularly on skeletal muscles that control complex movements and postures of the body and its limbs. However, the specific contribution of peripheral androgen-muscle interactions to the performance of elaborate behavioral displays in the natural world has never been examined. We study this issue in one of the only natural physiological models of animal acrobatics: the golden-collared manakin (Manacus vitellinus). In this tropical bird, males compete with each other and court females by producing firecracker-like wing- snaps and by rapidly dancing among saplings over the forest floor. To test how activation of peripheral androgen receptors (AR) influences this display, we treat reproductively active adult male birds with the peripherally selective antiandrogen bicalutamide (BICAL) and observe the effects of this manipulation on male display performance. We not only validate the peripheral specificity of BICAL in this species, but we also show that BICAL treatment reduces the frequency with which adult male birds perform their acrobatic display maneuvers and disrupts the overall structure and fine-scale patterning of these birds' main complex wing-snap sonation. In addition, this manipulation has no effect on the behavioral metrics associated with male motivation to display. Together, our findings help differentiate the various effects of peripheral and central AR on the performance of a complex sociosexual behavioral phenotype by indicating that peripheral AR can optimize the motor skills necessary for the production of an elaborate animal display. PMID:23782945

  11. Topological mimicry and epitope duplication in the guanylyl cyclase C receptor.

    PubMed Central

    Nandi, A.; Suguna, K.; Surolia, A.; Visweswariah, S. S.

    1998-01-01

    Guanylyl cyclase C (GCC) is the receptor for the gastrointestinal hormones, guanylin, and uroguanylin, in addition to the bacterial heat-stable enterotoxins, which are one of the major causes of watery diarrhea the world over. GCC is expressed in intestinal cells, colorectal tumor tissue and tumors originating from metastasis of the colorectal carcinoma. We have earlier generated a monoclonal antibody to human GCC, GCC:B10, which was useful for the immunohistochemical localization of the receptor in the rat intestine (Nandi A et al., 1997, J Cell Biochem 66:500-511), and identified its epitope to a 63-amino acid stretch in the intracellular domain of GCC. In view of the potential that this antibody has for the identification of colorectal tumors, we have characterized the epitope for GCC:B10 in this study. Overlapping peptide synthesis indicated that the epitope was contained in the sequence HIPPENIFPLE. This sequence was unique to GCC, and despite a short stretch of homology with serum amyloid protein and pertussis toxin, no cross reactivity was detected. The core epitope was delineated using a random hexameric phage display library, and two categories of sequences were identified, containing either a single, or two adjacent proline residues. No sequence identified by phage display was identical to the epitope present in GCC, indicating that phage sequences represented mimotopes of the native epitope. Alignment of these sequences with HIPPENIFPLE suggested duplication of the recognition motif, which was confirmed by peptide synthesis. These studies allowed us not only to define the requirements of epitope recognition by GCC:B10 monoclonal antibody, but also to describe a novel means of epitope recognition involving topological mimicry and probable duplication of the cognate epitope in the native guanylyl cyclase C receptor sequence. PMID:9792105

  12. Cytoplasmic Localization and the Choice of Ligand Determine Aggregate Formation by Androgen Receptor with Amplified Polyglutamine Stretch

    PubMed Central

    Becker, Matthias; Martin, Elke; Schneikert, Jean; Krug, Harald F.; Cato, Andrew C.B.

    2000-01-01

    Polyglutamine tract expansion in androgen receptor is a recognized cause of spinal and bulbar muscular atrophy (SBMA), an X-linked motor neuronopathy. Similar mutations have been identified in proteins associated with other neurodegenerative diseases. Recent studies have shown that amplified polyglutamine repeat stretches form cellular aggregates that may be markers for these neurodegenerative diseases. Here we describe conditions that lead to aggregate formation by androgen receptor with polyglutamine stretch amplification. In transfection experiments, the mutant, compared with the wild-type receptor, was delayed in its cytoplasmic–nuclear translocation and formed large cytoplasmic aggregates in the presence of androgen. The cytoplasmic environment appears crucial for this aggregation, since retention of both the wild-type and mutant receptors in this cellular compartment by the deletion of their nuclear localization signals resulted in massive aggregation. Conversely, rapid nuclear transport of both receptors brought about by deletion of their ligand binding domains did not result in aggregate formation. However, androgen antagonists that altered the conformation of the ligand binding domain and promoted varying rates of cytoplasmic–nuclear translocation all inhibited aggregate formation. This demonstrates that in addition to the cytoplasmic localization, a distinct contribution of the ligand binding domain of the receptor is necessary for the aggregation. The finding that antiandrogens inhibit aggregate formation may provide the basis for in vivo determination of the role of these structures in SBMA. PMID:10769019

  13. Androgen regulation of thromboxane A2/prostaglandin H2 receptor expression in human erythroleukemia cells.

    PubMed

    Matsuda, K; Mathur, R S; Duzic, E; Halushka, P V

    1993-12-01

    Thromboxane A2 (TxA2), a platelet aggregator and vasoconstrictor, has been implicated as a potential mediator of cardiovascular diseases. Abuse of androgenic steroids has been associated with thrombotic cardiovascular diseases. Human erythroleukemia (HEL) cells, a megakaryocyte-like cell line, express functional TxA2/prostaglandin H2 (PGH2) receptors with characteristics similar to those seen in platelets. This study characterized testosterone regulation of HEL cell TxA2/PGH2 receptors. TxA2/PGH2 receptor affinity (Kd) and density (Bmax) were determined via equilibrium binding experiments using the radiolabeled TxA2 mimetic (1S-[1 alpha,2 beta(5Z),3 alpha(1E,3R*),4 alpha])-7-(3-[3-hydroxy-4-(4'- iodophenoxy)-1-butenyl]-7-oxabicyclo[2.2.1]heptan-2-yl)-5-he ptenoic acid (125I-labeled BOP). Testosterone (200 nM) but not estradiol increased Bmax from 108 +/- 9 fmol/mg protein to 157 +/- 9 fmol/mg protein (n = 7 experiments; P < 0.01) without any significant change in Kd. Testosterone had no significant effect on alpha 2-adrenergic receptor density. The maximum increase in intracellular free calcium induced by the TxA2 agonists I-BOP or U-46619 was significantly (P < 0.005) greater in testosterone-treated cells compared with controls. Hydroxyflutamide (1 microM), an androgen-receptor antagonist, completely blocked the effect of testosterone (P < 0.01). Dihydrotestosterone, the active metabolite of testosterone, also increased Bmax in a concentration-dependent manner and was more potent than testosterone. The effect of testosterone to increase Bmax was significantly (P < 0.01) inhibited by coincubation with cycloheximide (0.1 microgram/ml) or actinomycin D (10 ng/ml). These results indicate that androgenic steroids regulate the expression of functional TxA2/PGH2 receptors in HEL cells. These findings may have relevance to cardiovascular disease. PMID:8279549

  14. Testosterone Reduces Knee Passive Range of Motion and Expression of Relaxin Receptor Isoforms via 5α-Dihydrotestosterone and Androgen Receptor Binding

    PubMed Central

    Dehghan, Firouzeh; Muniandy, Sekaran; Yusof, Ashril; Salleh, Naguib

    2014-01-01

    Ovarian steroids such as estrogen and progesterone have been reported to influence knee laxity. The effect of testosterone, however, remains unknown. This study investigated the effect of testosterone on the knee range of motion (ROM) and the molecular mechanisms that might involve changes in the expression of relaxin receptor isoforms, Rxfp1 and Rxfp2 in the patella tendon and lateral collateral ligament of the female rat knee. Ovariectomized adult female Wistar rats received three days treatment with peanut oil (control), testosterone (125 and 250 μg/kg) and testosterone (125 and 250 μg/kg) plus flutamide, an androgen receptor blocker or finasteride, a 5α-reductase inhibitor. Duplicate groups received similar treatment however in the presence of relaxin (25 ng/kg). A day after the last drug injection, knee passive ROM was measured by using a digital miniature goniometer. Both tendon and ligament were harvested and then analysed for protein and mRNA expression for Rxfp1 and Rxfp2 respectively. Knee passive ROM, Rxfp1 and Rxfp2 expression were significantly reduced following treatment with testosterone. Flutamide or finasteride administration antagonized the testosterone effect. Concomitant administration of testosterone and relaxin did not result in a significant change in knee ROM as compared to testosterone only treatment; however this was significantly increased following flutamide or finasteride addition. Testosterone effect on knee passive ROM is likely mediated via dihydro-testosterone (DHT), and involves downregulation of Rxfp1 and Rxfp2 expression, which may provide the mechanism underlying testosterone-induced decrease in female knee laxity. PMID:24642882

  15. Testosterone reduces knee passive range of motion and expression of relaxin receptor isoforms via 5α-dihydrotestosterone and androgen receptor binding.

    PubMed

    Dehghan, Firouzeh; Muniandy, Sekaran; Yusof, Ashril; Salleh, Naguib

    2014-01-01

    Ovarian steroids such as estrogen and progesterone have been reported to influence knee laxity. The effect of testosterone, however, remains unknown. This study investigated the effect of testosterone on the knee range of motion (ROM) and the molecular mechanisms that might involve changes in the expression of relaxin receptor isoforms, Rxfp1 and Rxfp2 in the patella tendon and lateral collateral ligament of the female rat knee. Ovariectomized adult female Wistar rats received three days treatment with peanut oil (control), testosterone (125 and 250 μg/kg) and testosterone (125 and 250 μg/kg) plus flutamide, an androgen receptor blocker or finasteride, a 5α-reductase inhibitor. Duplicate groups received similar treatment however in the presence of relaxin (25 ng/kg). A day after the last drug injection, knee passive ROM was measured by using a digital miniature goniometer. Both tendon and ligament were harvested and then analysed for protein and mRNA expression for Rxfp1 and Rxfp2 respectively. Knee passive ROM, Rxfp1 and Rxfp2 expression were significantly reduced following treatment with testosterone. Flutamide or finasteride administration antagonized the testosterone effect. Concomitant administration of testosterone and relaxin did not result in a significant change in knee ROM as compared to testosterone only treatment; however this was significantly increased following flutamide or finasteride addition. Testosterone effect on knee passive ROM is likely mediated via dihydro-testosterone (DHT), and involves downregulation of Rxfp1 and Rxfp2 expression, which may provide the mechanism underlying testosterone-induced decrease in female knee laxity. PMID:24642882

  16. Mechanism of the tissue-specific action of the selective androgen receptor modulator S-101479.

    PubMed

    Furuya, Kazuyuki; Yamamoto, Noriko; Ohyabu, Yuki; Morikyu, Teruyuki; Ishige, Hirohide; Albers, Michael; Endo, Yasuhisa

    2013-01-01

    Selective androgen receptor modulators (SARMs) comprise a new class of molecules that induce anabolic effects with fewer side effects than those of other anabolic agents. We previously reported that the novel SARM S-101479 had a tissue-selective bone anabolic effect with diminished side effects in female animals. However, the mechanism of its tissue selectivity is not well known. In this report, we show that S-101479 increased alkaline phosphatase activity and androgen receptor (AR) transcriptional activity in osteoblastic cell lines in the same manner as the natural androgen ligand dihydrotestosterone (DHT); conversely, stimulation of AR dimerization was very low compared with that of DHT (34.4%). S-101479 increased bone mineral content in ovariectomized rats without promoting endometrial proliferation. Yeast two-hybrid interaction assays revealed that DHT promoted recruitment of numerous cofactors to AR such as TIF2, SRC1, β-catenin, NCoA3, gelsolin and PROX1 in a dose-dependent manner. SARMs induced recruitment of fewer cofactors than DHT; in particular, S-101479 failed to induce recruitment of canonical p160 coactivators such as SRC1, TIF2 and notably NCoA3 but only stimulated binding of AR to gelsolin and PROX1. The results suggest that a full capability of the AR to dimerize and to effectively and unselectively recruit all canonical cofactors is not a prerequisite for transcriptional activity in osteoblastic cells and resulting anabolic effects in bone tissues. Instead, few relevant cofactors might be sufficient to promote AR activity in these tissues. PMID:23449329

  17. CDNA CLONING OF FATHEAD MINNOW (PIMEPHALES PROMELAS) ESTROGEN AND ANDROGEN RECEPTORS FOR USE IN STEROID RECEPTOR EXTRAPOLATION STUDIES FOR ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    cDNA Cloning of Fathead minnow (Pimephales promelas) Estrogen and Androgen Receptors for Use in Steroid Receptor Extrapolation Studies for Endocrine Disrupting Chemicals.

    Wilson, V.S.1,, Korte, J.2, Hartig P. 1, Ankley, G.T.2, Gray, L.E., Jr 1, , and Welch, J.E.1. 1U.S...

  18. CLONING AND IN VITRO EXPRESSION AND CHARACTERIZATION OF THE ANDROGEN RECEPTOR AND ISOLATION OF ESTROGEN RECEPTOR α FROM THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    In vitro screening assays designed to identify hormone mimics or antagonists typically use mammalian (rat, human) estrogen (ER) and androgen receptors (AR). Although we know that the amino acid sequences of steroid receptors in nonmammalian vertebrates are not identical to the ma...

  19. Single amino acid substitutions at 2 of 14 positions in an ultra-conserved region of the androgen receptor yield an androgen-binding domain that is reversibly thermolabile

    SciTech Connect

    Vasiliou, M.; Lumbroso, R.; Alvarado, C.

    1994-09-01

    The stereochemistry of the androgen receptor (AR) that is responsible for androgen-specific binding and for its contribution to the transregulatory attributes of an androgen-receptor complex are unknown. Our objective is to define structure-function relations of the human AR by correlating germline missense mutations at its X-linked locus with its resultant misbehavior. Subjects with Arg773Cys have complete androgen insensitivity. We and several other laboratories have reported that their genital skin fibroblasts (GSF) have negligible androgen-binding activity at 37{degrees}. We have found that Phe763Leu also causes CAI, but with approximately 10 fmol/mg protein androgen-binding activity at 37{degrees} (R-deficient). Within COS-1 cells transfected with each mutant AR cDNA, Phe763Leu and Arg773Cys androgen-binding activities are reversibly thermolabile, by a factor of 2, at 37{degrees} versus 22{degrees}, only in the presence of androgen; in the absence of androgen they are thermostable at 37{degrees}. We have discovered that (for a reason yet unknown) the GSF from a third family with Arg773Cys (and no other coding sequence mutation) have 20-40 mol/mg protein of androgen-binding activity at 37{degrees} when measured with 3-6 nFM androgen. This activity reversibly doubles at 22{degrees}. The reversible thermolability of an AR with Arg773Cys (and probably with Phe763Leu) is demonstrable within GSF. Ligand-dependence of this thermolability implies that ligand induces these mutant AR to undergo a deviant conformational change in, or near, a 14-aa region that shares 90% identity/similarity with its closest receptor relatives.

  20. Screening of bisphenol A, triclosan and paraben analogues as modulators of the glucocorticoid and androgen receptor activities.

    PubMed

    Kolšek, Katra; Gobec, Martina; Mlinarič Raščan, Irena; Sollner Dolenc, Marija

    2015-02-01

    A homeostasis of the glucocorticoid and androgen endocrine system is essential to human health. Their disturbance can lead to various diseases, for example cardiovascular, inflammatory and autoimmune diseases, infertility, cancer. Fifteen widely used industrial chemicals that disrupt endocrine activity were selected for evaluation of potential (anti)glucocorticoid and (anti)androgenic activities. The human breast carcinoma MDA-kb2 cell line was utilized for reporter gene assays, since it expresses both the androgen and the glucocorticoid-responsive reporter. Two new antiandrogens, 4,4'-sulfonylbis(2-methylphenol) (dBPS) and 4,4'-thiodiphenol (THIO), and two new antiglucocorticoids, bisphenol Z and its analog bis[4-(2-hydroxyethoxy)phenyl] sulfone (BHEPS) were identified. Moreover, four new glucocorticoid agonists (methyl paraben, ethyl paraben, propyl paraben and bisphenol F) were found. To elucidate the structure-activity relationship of bisphenols, we performed molecular docking experiments with androgen and glucocorticoid receptor. These docking experiments had shown that bulky structures such as BHEPS and bisphenol Z act as antiglucocorticoid, because they are positioned toward helix H12 in the antagonist conformation and could therefore be responsible for H12 conformational change and the switch between agonistic and antagonistic conformation of receptor. On the other hand smaller structures cannot interact with H12. The results of in vitro screening of fifteen industrial chemicals as modulators of the glucocorticoid and androgen receptor activities demand additional in vivo testing of these chemicals for formulating any relevant hazard identification to human health. PMID:25192815

  1. Effects of Sorafenib on C-Terminally Truncated Androgen Receptor Variants in Human Prostate Cancer Cells

    PubMed Central

    Zengerling, Friedemann; Streicher, Wolfgang; Schrader, Andres J.; Schrader, Mark; Nitzsche, Bianca; Cronauer, Marcus V.; Höpfner, Michael

    2012-01-01

    Recent evidence suggests that the development of castration resistant prostate cancer (CRPCa) is commonly associated with an aberrant, ligand-independent activation of the androgen receptor (AR). A putative mechanism allowing prostate cancer (PCa) cells to grow under low levels of androgens, is the expression of constitutively active, C-terminally truncated AR lacking the AR-ligand binding domain (LBD). Due to the absence of a LBD, these receptors, termed ARΔLBD, are unable to respond to any form of anti-hormonal therapies. In this study we demonstrate that the multikinase inhibitor sorafenib inhibits AR as well as ARΔLBD-signalling in CRPCa cells. This inhibition was paralleled by proteasomal degradation of the AR- and ARΔLBD-molecules. In line with these observations, maximal antiproliferative effects of sorafenib were achieved in AR and ARΔLBD-positive PCa cells. The present findings warrant further investigations on sorafenib as an option for the treatment of advanced AR-positive PCa. PMID:23109869

  2. Effects of sorafenib on C-terminally truncated androgen receptor variants in human prostate cancer cells.

    PubMed

    Zengerling, Friedemann; Streicher, Wolfgang; Schrader, Andres J; Schrader, Mark; Nitzsche, Bianca; Cronauer, Marcus V; Höpfner, Michael

    2012-01-01

    Recent evidence suggests that the development of castration resistant prostate cancer (CRPCa) is commonly associated with an aberrant, ligand-independent activation of the androgen receptor (AR). A putative mechanism allowing prostate cancer (PCa) cells to grow under low levels of androgens, is the expression of constitutively active, C-terminally truncated AR lacking the AR-ligand binding domain (LBD). Due to the absence of a LBD, these receptors, termed ARΔLBD, are unable to respond to any form of anti-hormonal therapies. In this study we demonstrate that the multikinase inhibitor sorafenib inhibits AR as well as ARΔLBD-signalling in CRPCa cells. This inhibition was paralleled by proteasomal degradation of the AR- and ARΔLBD-molecules. In line with these observations, maximal antiproliferative effects of sorafenib were achieved in AR and ARΔLBD-positive PCa cells. The present findings warrant further investigations on sorafenib as an option for the treatment of advanced AR-positive PCa. PMID:23109869

  3. Preclinical pharmacology of FL442, a novel nonsteroidal androgen receptor modulator.

    PubMed

    Poutiainen, Pekka K; Huhtala, Tuulia; Jääskeläinen, Tiina; Petsalo, Aleksanteri; Küblbeck, Jenni; Kaikkonen, Sanna; Palvimo, Jorma J; Raunio, Hannu; Närvänen, Ale; Peräkylä, Mikael; Juvonen, Risto O; Honkakoski, Paavo; Laatikainen, Reino; Pulkkinen, Juha T

    2014-04-25

    The preclinical profiles of two most potent compounds of our recently published cycloalkane[d]isoxazole pharmacophore-based androgen receptor (AR) modulators, FL442 (4-(3a,4,5,6,7,7a-hexahydro-benzo[d]isoxazol-3-yl)-2-(trifluoromethyl)benzonitrile) and its nitro analog FL425 (3-(4-nitro-3-(trifluoromethyl)phenyl)-3a,4,5,6,7,7a-hexahydrobenzo[d]isoxazole), were explored to evaluate their druggability for the treatment of AR dependent prostate cancer. The studies revealed that both compounds are selective to AR over other closely related steroid hormone receptors and that FL442 exhibits equal inhibition efficiency towards the androgen-responsive LNCaP prostate cancer cell line as the most widely used antiandrogen bicalutamide and the more recently discovered enzalutamide. Notably, FL442 maintains antiandrogenic activity with enzalutamide-activated AR mutant F876L. In contrast to bicalutamide, FL442 does not stimulate the VCaP prostate cancer cells which express elevated levels of the AR. Distribution analyses showed that [(14)CN]FL442 accumulates strongly in the mouse prostate. In spite of its low plasma concentration obtained by intraperitoneal administration, FL442 significantly inhibited LNCaP xenograft tumor growth. These findings provide a preclinical proof for FL442 as a promising AR targeted candidate for a further optimization. PMID:24565895

  4. An imaging agent to detect androgen receptor and its active splice variants in prostate cancer

    PubMed Central

    Imamura, Yusuke; Tien, Amy H.; Pan, Jinhe; Leung, Jacky K.; Banuelos, Carmen A.; Jian, Kunzhong; Wang, Jun; Mawji, Nasrin R.; Fernandez, Javier Garcia; Lin, Kuo-Shyan; Andersen, Raymond J.; Sadar, Marianne D.

    2016-01-01

    Constitutively active splice variants of androgen receptor (AR-Vs) lacking ligand-binding domain (LBD) are a mechanism of resistance to androgen receptor LBD–targeted (AR LBD–targeted) therapies for metastatic castration-resistant prostate cancer (CRPC). There is a strong unmet clinical need to identify prostate cancer patients with AR-V–positive lesions to determine whether they will benefit from further AR LBD–targeting therapies or should receive taxanes or investigational drugs like EPI-506 or galeterone. Both EPI-506 (NCT02606123) and galeterone (NCT02438007) are in clinical trials and are proposed to have efficacy against lesions that are positive for AR-Vs. AR activation function-1 (AF-1) is common to the N-terminal domains of full-length AR and AR-Vs. Here, we provide proof of concept for developing imaging compounds that directly bind AR AF-1 to detect both AR-Vs and full-length AR. 123I-EPI-002 had specific binding to AR AF-1, which enabled direct visualization of CRPC xenografts that express full-length AR and AR-Vs. Our findings highlight the potential of 123I-EPI-002 as an imaging agent for the detection of full-length AR and AR-Vs in CRPC. PMID:27525313

  5. Lead evaluation of tetrahydroquinolines as nonsteroidal selective androgen receptor modulators for the treatment of osteoporosis.

    PubMed

    Nagata, Naoya; Furuya, Kazuyuki; Oguro, Nao; Nishiyama, Daisuke; Kawai, Kentaro; Yamamoto, Noriko; Ohyabu, Yuki; Satsukawa, Masahiro; Miyakawa, Motonori

    2014-01-01

    Tetrahydroquinoline (THQ) was deemed to be a suitable scaffold for our nonsteroidal selective androgen receptor modulator (SARM) concept. We adapted the strategy of switching the antagonist function of cyano-group-containing THQ (CN-THQ) to the agonist function and optimized CN-THQ as an orally available drug candidate with suitable pharmacological and ADME profiles. Based on binding mode analyses and synthetic accessibility, we designed and synthesized a compound that possesses a para-substituted aromatic ring attached through an amide linker. The long-tail THQ derivative 6-acetamido-N-(2-(8-cyano-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinolin-4-yl)-2-methylpropyl)nicotinamide (1 d), which bears a para-acetamide-substituted aromatic group, showed an appropriate in vitro biological profile, as expected. We considered that the large conformational change at Trp741 of the androgen receptor (AR) and the hydrogen bond between 1 d and helix 12 of the AR could maintain the structure of the AR in its agonist form; indeed, 1 d displays strong AR agonistic activity. Furthermore, 1 d showed an appropriate in vivo profile for use as an orally available SARM, displaying clear tissue selectivity, with a separation between its desirable osteoanabolic effect on femoral bone mineral density and its undesirable virilizing effects on the uterus and clitoral gland in a female osteoporosis model. PMID:24273094

  6. Androgen receptor variant-driven prostate cancer: clinical implications and therapeutic targeting.

    PubMed

    Antonarakis, E S; Armstrong, A J; Dehm, S M; Luo, J

    2016-09-01

    While there are myriad mechanisms of primary and acquired resistance to conventional and next-generation hormonal therapies in prostate cancer, the potential role of androgen receptor splice variants (AR-Vs) has recently gained momentum. AR-Vs are abnormally truncated isoforms of the androgen receptor (AR) protein that lack the COOH-terminal domain but retain the NH2-terminal domain and DNA-binding domain and are thus constitutively active even in the absence of ligands. Although multiple preclinical studies have previously implicated AR-Vs in the development of castration resistance as well as resistance to abiraterone and enzalutamide, recent technological advances have made it possible to reliably detect and quantify AR-Vs from human clinical tumor specimens including blood samples. Initial clinical studies have now shown that certain AR-Vs, in particular AR-V7, may be associated with resistance to abiraterone and enzalutamide but not taxane chemotherapies when detected in circulating tumor cells. Efforts are now underway to clinically validate AR-V7 as a relevant treatment-selection biomarker in the context of other key genomic aberrations in men with metastatic castration-resistant prostate cancer. Additional efforts are underway to therapeutically target both AR and AR-Vs either directly or indirectly. Whether AR-Vs represent drivers of castration-resistant prostate cancer, or whether they are simply passenger events associated with aggressive disease or clonal heterogeneity, will ultimately be answered only through these types of clinical trials. PMID:27184811

  7. Androgen Receptor Coactivator ARID4B Is Required for the Function of Sertoli Cells in Spermatogenesis.

    PubMed

    Wu, Ray-Chang; Zeng, Yang; Pan, I-Wen; Wu, Mei-Yi

    2015-09-01

    Defects in spermatogenesis, a process that produces spermatozoa inside seminiferous tubules of the testis, result in male infertility. Spermatogenic progression is highly dependent on a microenvironment provided by Sertoli cells, the only somatic cells and epithelium of seminiferous tubules. However, genes that regulate such an important activity of Sertoli cells are poorly understood. Here, we found that AT-rich interactive domain 4B (ARID4B), is essential for the function of Sertoli cells to regulate spermatogenesis. Specifically, we generated Sertoli cell-specific Arid4b knockout (Arid4bSCKO) mice, and showed that the Arid4bSCKO male mice were completely infertile with impaired testis development and significantly reduced testis size. Importantly, severe structural defects accompanied by loss of germ cells and Sertoli cell-only phenotype were found in many seminiferous tubules of the Arid4bSCKO testes. In addition, maturation of Sertoli cells was significantly delayed in the Arid4bSCKO mice, associated with delayed onset of spermatogenesis. Spermatogenic progression was also defective, showing an arrest at the round spermatid stage in the Arid4bSCKO testes. Interestingly, we showed that ARID4B functions as a "coactivator" of androgen receptor and is required for optimal transcriptional activation of reproductive homeobox 5, an androgen receptor target gene specifically expressed in Sertoli cells and critical for spermatogenesis. Together, our study identified ARID4B to be a key regulator of Sertoli cell function important for male germ cell development. PMID:26258622

  8. Whole Genome Duplications Shaped the Receptor Tyrosine Kinase Repertoire of Jawed Vertebrates

    PubMed Central

    Brunet, Frédéric G.; Volff, Jean-Nicolas; Schartl, Manfred

    2016-01-01

    The receptor tyrosine kinase (RTK) gene family, involved primarily in cell growth and differentiation, comprises proteins with a common enzymatic tyrosine kinase intracellular domain adjacent to a transmembrane region. The amino-terminal portion of RTKs is extracellular and made of different domains, the combination of which characterizes each of the 20 RTK subfamilies among mammals. We analyzed a total of 7,376 RTK sequences among 143 vertebrate species to provide here the first comprehensive census of the jawed vertebrate repertoire. We ascertained the 58 genes previously described in the human and mouse genomes and established their phylogenetic relationships. We also identified five additional RTKs amounting to a total of 63 genes in jawed vertebrates. We found that the vertebrate RTK gene family has been shaped by the two successive rounds of whole genome duplications (WGD) called 1R and 2R (1R/2R) that occurred at the base of the vertebrates. In addition, the Vegfr and Ephrin receptor subfamilies were expanded by single gene duplications. In teleost fish, 23 additional RTK genes have been retained after another expansion through the fish-specific third round (3R) of WGD. Several lineage-specific gene losses were observed. For instance, birds have lost three RTKs, and different genes are missing in several fish sublineages. The RTK gene family presents an unusual high gene retention rate from the vertebrate WGDs (58.75% after 1R/2R, 64.4% after 3R), resulting in an expansion that might be correlated with the evolution of complexity of vertebrate cellular communication and intracellular signaling. PMID:27260203

  9. Whole Genome Duplications Shaped the Receptor Tyrosine Kinase Repertoire of Jawed Vertebrates.

    PubMed

    Brunet, Frédéric G; Volff, Jean-Nicolas; Schartl, Manfred

    2016-01-01

    The receptor tyrosine kinase (RTK) gene family, involved primarily in cell growth and differentiation, comprises proteins with a common enzymatic tyrosine kinase intracellular domain adjacent to a transmembrane region. The amino-terminal portion of RTKs is extracellular and made of different domains, the combination of which characterizes each of the 20 RTK subfamilies among mammals. We analyzed a total of 7,376 RTK sequences among 143 vertebrate species to provide here the first comprehensive census of the jawed vertebrate repertoire. We ascertained the 58 genes previously described in the human and mouse genomes and established their phylogenetic relationships. We also identified five additional RTKs amounting to a total of 63 genes in jawed vertebrates. We found that the vertebrate RTK gene family has been shaped by the two successive rounds of whole genome duplications (WGD) called 1R and 2R (1R/2R) that occurred at the base of the vertebrates. In addition, the Vegfr and Ephrin receptor subfamilies were expanded by single gene duplications. In teleost fish, 23 additional RTK genes have been retained after another expansion through the fish-specific third round (3R) of WGD. Several lineage-specific gene losses were observed. For instance, birds have lost three RTKs, and different genes are missing in several fish sublineages. The RTK gene family presents an unusual high gene retention rate from the vertebrate WGDs (58.75% after 1R/2R, 64.4% after 3R), resulting in an expansion that might be correlated with the evolution of complexity of vertebrate cellular communication and intracellular signaling. PMID:27260203

  10. Enhancement of gene transactivation activity of androgen receptor by hepatitis B virus X protein

    SciTech Connect

    Zheng Yanyan; Chen Wenling; Ma, W.-L. Maverick; Chang Chawnshang; Ou, J.-H. James . E-mail: jamesou@hsc.usc.edu

    2007-07-05

    Hepatitis B virus (HBV) X protein (HBx) is a regulatory protein that is required for efficient replication of HBV in its natural host. In this report, we demonstrate by co-immunoprecipitation experiments that HBx can physically bind to the androgen receptor (AR), which is a nuclear hormone receptor that is expressed in many different tissues including the liver. This observation is further supported by confocal microscopy, which reveals that HBx can alter the subcellular localization of the AR both in the presence and in the absence of dihydrotestosterone (DHT). Further studies indicate that HBx can enhance the gene transactivation activity of AR by enhancing its DNA binding activity in a DHT-dependent manner. However, HBx does not remain associated with AR on the DNA. As AR can regulate the expression of a number of cellular genes, our results raise the possibility that HBV pathogenesis may be mediated in part via the interaction between HBx and AR.

  11. Androgen receptor silences thioredoxin-interacting protein and competitively inhibits glucocorticoid receptor-mediated apoptosis in pancreatic β-Cells.

    PubMed

    Harada, Naoki; Katsuki, Takahiro; Takahashi, Yuji; Masuda, Tatsuya; Yoshinaga, Mariko; Adachi, Tetsuya; Izawa, Takeshi; Kuwamura, Mitsuru; Nakano, Yoshihisa; Yamaji, Ryoichi; Inui, Hiroshi

    2015-06-01

    Androgen receptor (AR) is known to bind to the same cis-element that glucocorticoid receptor (GR) binds to. However, the effects of androgen signaling on glucocorticoid signaling have not yet been elucidated. Here, we investigated the effects of testosterone on dexamethasone (DEX, a synthetic glucocorticoid)-induced apoptosis of pancreatic β-cells, which might be involved in the pathogenesis of type 2 diabetes mellitus in males. We used INS-1 #6 cells, which were isolated from the INS-1 pancreatic β-cell line and which express high levels of AR. Testosterone and dihydrotestosterone inhibited apoptosis induced by DEX in INS-1 #6 cells. AR knockdown and the AR antagonist hydroxyflutamide each diminished the anti-apoptotic effects of testosterone. AR was localized in the nucleus of both INS-1 #6 cells and pancreatic β-cells of male rats. Induction of thioredoxin-interacting protein (TXNIP) is known to cause pro-apoptotic effects in β-cells. Testosterone suppressed the DEX-induced increase of TXNIP at the transcriptional level. A Chromatin immunoprecipitation assays showed that both AR and GR competitively bound to the TXNIP promoter in ligand-dependent manners. Recombinant DNA-binding domain of AR bound to the same cis-element of the TXNIP promoter that GR binds to. Our results show that AR and GR competitively bind to the same cis-element of TXNIP promoter as a silencer and enhancer, respectively. These results indicate that androgen signaling functionally competes with glucocorticoid signaling in pancreatic β-cell apoptosis. PMID:25639671

  12. β-Catenin Binds to the Activation Function 2 Region of the Androgen Receptor and Modulates the Effects of the N-Terminal Domain and TIF2 on Ligand-Dependent Transcription

    PubMed Central

    Song, Liang-Nian; Herrell, Roger; Byers, Stephen; Shah, Salimuddin; Wilson, Elizabeth M.; Gelmann, Edward P.

    2003-01-01

    β-Catenin is a multifunctional molecule that is activated by signaling through WNT receptors. β-Catenin can also enhance the transcriptional activity of some steroid hormone receptors such as the androgen receptor and retinoic acid receptor α. Androgens can affect nuclear translocation of β-catenin and influence its subcellular distribution. Using mammalian two-hybrid binding assays, analysis of reporter gene transcription, and coimmunoprecipitation, we now show that β-catenin binds to the androgen receptor ligand-binding domain (LBD) and modulates the transcriptional effects of TIF2 and the androgen receptor N-terminal domain (NTD). In functional assays, β-catenin bound to androgen receptor only in the presence of ligand agonists, not antagonists. β-Catenin binding to the androgen receptor LBD was independent of and cooperative with the androgen receptor NTD and the p160 coactivator TIF2, both of which bind to the activation function 2 (AF-2) region of the androgen receptor. Different mutations of androgen receptor helix 3 amino acids disrupted binding of androgen receptor NTD and β-catenin. β-Catenin, androgen receptor NTD, and TIF2 binding to the androgen receptor LBD were affected similarly by a subset of helix 12 mutations, but disruption of two sites on helix 12 affected only binding of β-catenin and not of TIF2 or the androgen receptor NTD. Mutational disruption of each of five LXXLL peptide motifs in the β-catenin armadillo repeats did not disrupt either binding to androgen receptor or transcriptional coactivation. ICAT, an inhibitor of T-cell factor 4 (TCF-4), and E-cadherin binding to β-catenin also blocked binding of the androgen receptor LBD. We also demonstrated cross talk between the WNT and androgen receptor signaling pathways because excess androgen receptor could interfere with WNT signaling and excess TCF-4 inhibited the interaction of β-catenin and androgen receptor. Taken together, the data show that β-catenin can bind to the

  13. A Phase II Study Evaluating the Role of Androgen Receptors as Targets for Therapy of Pre-treated Post-menopausal Patients With ER/PgR-negative/AR-positive or ER and/or PgRpositive/ AR-positive Metastatic Breast Cancer (ARTT)

    ClinicalTrials.gov

    2015-12-30

    Metastatic Breastcancer; Estrogen Receptor Positive Breast Cancer; Estrogen Receptor Negative Neoplasm; Progesterone Receptor Positive Tumor; Progesterone Receptor Negative Neoplasm; Androgen Receptor Gene Overexpression

  14. BTG2 is an LXXLL-dependent co-repressor for androgen receptor transcriptional activity

    SciTech Connect

    Hu, Xu-Dong; Meng, Qing-Hui; Xu, Jia-Ying; Jiao, Yang; Ge, Chun-Min; Jacob, Asha; Wang, Ping; Rosen, Eliot M; Fan, Saijun

    2011-01-28

    Research highlights: {yields} BTG2 associates with AR, androgen causes an increase of the interaction. {yields} BTG2 as a co-repressor inhibits the AR-mediated transcription activity. {yields} BTG2 inhibits the transcription activity and expression of PSA. {yields} An intact {sup 92}LxxLL{sup 96} motif is essential and necessary for these activities of BTG2, while the {sup 20}LxxLL{sup 24} motif is not required. {yields} Ectopic expression of BTG2 reduces proliferation of prostate cancer cells. -- Abstract: The tumor suppressor gene, BTG2 has been down-regulated in prostate cancer and the ectopic expression of this gene has been shown to inhibit prostate cancer cell growth. Sequence analysis revealed that the BTG2 protein contains two leucine-rich motifs ({sup 20}LxxLL{sup 24} and {sup 92}LxxLL{sup 96}), which are usually found in nuclear receptor co-factors. Based on this, we postulated that there will be an association between BTG2 and AR. In this study, we discovered that BTG2 directly bound to the androgen receptor (AR) in the absence of 5{alpha}-dihydrotestosterone (DHT), and in the presence of the androgen, this interaction was increased. BTG2 bearing the mutant {sup 20}LxxLL{sup 24} motif bound to AR equally efficient as the wild-type BTG2, while BTG2 bearing the mutant {sup 92}LxxLL{sup 96} motif failed to interact with AR. Functional studies indicated that ectopic expression of BTG2 caused a significant inhibition of AR-mediated transcriptional activity and a decreased growth of prostate cancer cells. Androgen-induced promoter activation and expression of prostate-specific antigen (PSA) are significantly attenuated by BTG2. The intact {sup 92}LxxLL{sup 96} motif is required for these activities. These findings, for the first time, demonstrate that BTG2 complexes with AR via an LxxLL-dependent mechanism and may play a role in prostate cancer via modulating the AR signaling pathway.

  15. Estrogen receptor (ER) agonists and androgen receptor (AR) antagonists in effluents from Norwegian North Sea oil production platforms.

    PubMed

    Tollefsen, Knut-Erik; Harman, Christopher; Smith, Andy; Thomas, Kevin V

    2007-03-01

    The in vitro estrogen receptor (ER) agonist and androgen receptor (AR) antagonist potencies of offshore produced water effluents collected from the Norwegian Sector were determined using recombinant yeast estrogen and androgen screens. Solid phase extraction (SPE) concentrates of the effluents showed E2 agonist activities similar to those previously reported for the United Kingdom (UK) Continental Shelf (<0.1-4 ng E2 L(-1)). No activity was detected in the filtered oil droplets suggesting that produced water ER activity is primarily associated with the dissolved phase. Targeted analysis for methyl- to nonyl-substituted alkylphenol isomers show the occurrence of known ER agonists in the analysed samples. For the first time, AR antagonists were detected in both the dissolved and oil associated phase at concentrations of between 20 and 8000 microg of flutamide equivalents L(-1). The identity of the AR antagonists is unknown, however this represents a significant input into the marine environment of unknown compounds that exert a known biological effect. It is recommended that further analysis using techniques such as bioassay-directed analysis is performed to identify the compounds/groups of compounds that are responsible in order to improve the assessment of the risk posed by produced water discharges to the marine environment. PMID:17258235

  16. Effects of HO-/MeO-PBDEs on androgen receptor: in vitro investigation and helix 12-involved MD simulation.

    PubMed

    Wang, Xiaoxiang; Yang, Huaiyu; Hu, Xinxin; Zhang, Xiaowei; Zhang, Qiansen; Jiang, Hualiang; Shi, Wei; Yu, Hongxia

    2013-10-15

    Hydroxylated and methoxylated polybrominated diphenyl ethers (HO-/MeO-PBDEs) have received increasing attention for their potential endocrine disrupting activities and widely environmental distribution. However, little information is available for the anti-androgenic activities, and the molecular mechanism of interactions with androgen receptor (AR) is not fully understood. In the present study, cell line assay and computational simulation were integrated to systematically explore the molecular mechanism of interactions between chemicals and AR. The metabolites with similar molecular structures exhibited different anti-androgenic activity while none of them showed androgenic activity. According to the multisystem molecular dynamics simulation, minute differences in the structure of ligands induced dramatic different conformational transition of AR-ligand binding domain (LBD). The Helix12 (H12) component of active ligands occupied AR-LBD could become stable, but this component continued to fluctuate in inactive ligands occupied AR-LBD. Settling time and reposition of H12 obtained in dynamics process are important factors governing anti-androgenic activities. The related settling times were characteristic of anti-androgenic potencies of the tested chemicals. Overall, in our study, the stable reposition of H12 is characterized as a computational mark for identifying AR antagonists from PBDE metabolites, or even other various environmental pollutants. PMID:24044724

  17. Three cases of intraocular mesectodermal leiomyoma expressing progesterone and androgen receptors

    PubMed Central

    Quhill, H; Rennie, I G; Rundle, P A; Mudhar, H S

    2013-01-01

    Background/Aims A prospective study identified three patients between 2004 and 2010 with mesectodermal leiomyoma. The study was conducted to analyse the presence or absence of sex steroid hormone receptors in mesectodermal leiomyomas. Methods The clinical features were collated. All three patients had operative procedures to either remove or sample the mesectodermal leiomyomas. The tissue was fixed in formalin and exposed to conventional histological processing. Immunohistochemistry using antibodies to androgen (AR), oestrogen (ER), and progesterone (PR) receptors was performed, followed by stain scoring to assess for expression status. Results All three cases were confirmed by histology to be examples of mesectodermal leiomyomas. All three expressed sex steroid hormone receptors. One case expressed both PR and AR, one case PR only and another case AR only. None of the cases expressed ER receptors. Conclusion All three cases displayed some sex steroid hormone receptor expression. This is supportive evidence that sex steroid hormones may have a role in the pathogenesis of this tumour and suggest that it may be amenable to hormonal manipulation therapy, in a manner similar to conventional uterine leiomyomas. PMID:23519275

  18. Transcription of Nrdp1 by the androgen receptor is regulated by nuclear filamin A in prostate cancer.

    PubMed

    Savoy, Rosalinda M; Chen, Liqun; Siddiqui, Salma; Melgoza, Frank U; Durbin-Johnson, Blythe; Drake, Christiana; Jathal, Maitreyee K; Bose, Swagata; Steele, Thomas M; Mooso, Benjamin A; D'Abronzo, Leandro S; Fry, William H; Carraway, Kermit L; Mudryj, Maria; Ghosh, Paramita M

    2015-06-01

    Prostate cancer (PCa) progression is regulated by the androgen receptor (AR); however, patients undergoing androgen-deprivation therapy (ADT) for disseminated PCa eventually develop castration-resistant PCa (CRPC). Results of previous studies indicated that AR, a transcription factor, occupies distinct genomic loci in CRPC compared with hormone-naïve PCa; however, the cause of this distinction was unknown. The E3 ubiquitin ligase Nrdp1 is a model AR target modulated by androgens in hormone-naïve PCa but not in CRPC. Using Nrdp1, we investigated how AR switches transcription programs during CRPC progression. The proximal Nrdp1 promoter contains an androgen response element (ARE); we demonstrated AR binding to this ARE in androgen-sensitive PCa. Analysis of hormone-naive human prostatectomy specimens revealed correlation between Nrdp1 and AR expression, supporting AR regulation of NRDP1 levels in androgen-sensitive tissue. However, despite sustained AR levels, AR binding to the Nrdp1 promoter and Nrdp1 expression were suppressed in CRPC. Elucidation of the suppression mechanism demonstrated correlation of NRDP1 levels with nuclear localization of the scaffolding protein filamin A (FLNA) which, as we previously showed, is itself repressed following ADT in many CRPC tumors. Restoration of nuclear FLNA in CRPC stimulated AR binding to Nrdp1 ARE, increased its transcription, and augmented NRDP1 protein expression and responsiveness to ADT, indicating that nuclear FLNA controls AR-mediated androgen-sensitive Nrdp1 transcription. Expression of other AR-regulated genes lost in CRPC was also re-established by nuclear FLNA. Thus, our results indicate that nuclear FLNA promotes androgen-dependent AR-regulated transcription in PCa, while loss of nuclear FLNA in CRPC alters the AR-regulated transcription program. PMID:25759396

  19. Granulosa Cell-Specific Androgen Receptors Are Critical Regulators of Ovarian Development and Function

    PubMed Central

    Sen, Aritro; Hammes, Stephen R.

    2010-01-01

    The physiological significance of androgens in female reproduction was unclear until female mice with global knockout of androgen receptor (AR) expression were found to have reduced fertility with abnormal ovarian function. However, because ARs are expressed in a myriad of reproductive tissues, including the hypothalamus, pituitary, and various ovarian cells, the role of tissue-specific ARs in regulating female fertility remained unknown. To examine the importance of ovarian ARs in female reproduction, we generated granulosa cell (GC)- and oocyte-specific AR-knockout (ARKO) mice by crossing AR-flox mice with MisRIIcre (GC-specific) or growth differentiation factor growth differentiation factor-9cre (oocyte-specific) mice. Relative to heterozygous and wild-type mice, GC-specific ARKO mice had premature ovarian failure and were subfertile, with longer estrous cycles and fewer ovulated oocytes. In addition, ovaries from GC-specific knockout mice contained more preantral and atretic follicles, with fewer antral follicles and corpus lutea. Finally, in vitro growth of follicles from GC-specific AR-null mice was slower than follicles from wild-type animals. In contrast to GC-specific AR-null mice, fertility, estrous cycles, and ovarian morphology of oocyte-specific ARKO mice were normal, although androgens no longer promoted oocyte maturation in these animals. Together, our data indicate that nearly all reproductive phenotypes observed in global ARKO mice can be explained by the lack of AR expression in GCs. These GC-specific ARs appear to promote preantral follicle growth and prevent follicular atresia; thus they are essential for normal follicular development and fertility. PMID:20501640

  20. Restoration of spermatogenesis and male fertility using an androgen receptor transgene.

    PubMed

    Walker, William H; Easton, Evan; Moreci, Rebecca S; Toocheck, Corey; Anamthathmakula, Prashanth; Jeyasuria, Pancharatnam

    2015-01-01

    Androgens signal through the androgen receptor (AR) to regulate male secondary sexual characteristics, reproductive tract development, prostate function, sperm production, bone and muscle mass as well as body hair growth among other functions. We developed a transgenic mouse model in which endogenous AR expression was replaced by a functionally modified AR transgene. A bacterial artificial chromosome (BAC) was constructed containing all AR exons and introns plus 40 kb each of 5' and 3' regulatory sequence. Insertion of an internal ribosome entry site and the EGFP gene 3' to AR allowed co-expression of AR and EGFP. Pronuclear injection of the BAC resulted in six founder mice that displayed EGFP production in appropriate AR expressing tissues. The six founder mice were mated into a Sertoli cell specific AR knockout (SCARKO) background in which spermatogenesis is blocked at the meiosis stage of germ cell development. The AR-EGFP transgene was expressed in a cyclical manner similar to that of endogenous AR in Sertoli cells and fertility was restored as offspring were produced in the absence of Sertoli cell AR. Thus, the AR-EGFP transgene under the control of AR regulatory elements is capable of rescuing AR function in a cell selective, AR-null background. These initial studies provide proof of principle that a strategy employing the AR-EGFP transgene can be used to understand AR functions. Transgenic mice expressing selective modifications of the AR-EGFP transgene may provide crucial information needed to elicit the molecular mechanisms by which AR acts in the testis and other androgen responsive tissues. PMID:25803277

  1. Expression and significance of androgen receptor coactivators in urothelial carcinoma of the bladder.

    PubMed

    Boorjian, Stephen A; Heemers, Hannelore V; Frank, Igor; Farmer, Sara A; Schmidt, Lucy J; Sebo, Thomas J; Tindall, Donald J

    2009-03-01

    Urothelial carcinoma (UC) of the bladder is approximately three times more common in men than women. While the etiology for this gender difference in incidence remains unknown, a role for androgen receptor (AR) signaling has been suggested. The mechanisms by which AR activity is regulated in UC cells, however, are largely elusive. Here, we explore the significance of coregulators that are critical for the formation of a functional AR transcriptional complex, in UC cells. Using two AR-positive UC cell lines, TCC-SUP and UMUC3, we demonstrate the expression of the coactivators NCOA1, NCOA2, NCOA3, CREBBP, and EP300 in UC cells. small interfering RNA-mediated knockdown of the AR or any of these coactivators markedly impacted cell viability and abrogated androgen-dependent cell proliferation. Noteworthy, contrary to AR-positive prostate cancer cells, expression of these AR-associated coactivators was not androgen regulated in UC cells. To assess the clinical relevance of coactivator expression, we performed immunohistochemistry on paraffin-embedded sections from 55 patients with UC of the bladder. We found that while 24 out of 55 (44%) of tumors expressed the AR, each of the coactivators was expressed by 85-100% of the bladder cancers. Moreover, we noted a significant downregulation of NCOA1 expression in tumors versus adjacent, non-tumor bladder urothelium, with a mean of 68% (range 0-100) of tumor cells demonstrating NCOA1 staining versus a mean of 81% (range 0-90) of non-tumor cells (P=0.03). Taken together, our data suggest an important role for AR-associated coactivators in UC and point toward differences in the regulation of AR activity between bladder and prostate cancer cells. PMID:18845648

  2. ANALYSIS OF ANDROGEN- AND EGF-RECEPTOR EXPRESSION IN THE FETAL RAT PHALLUS AFTER EXPOSURE TO VINCLOZOLIN

    EPA Science Inventory

    Analysis of Androgen- and EGF-Receptor Expression in the Fetal Rat Phallus After Exposure to Vinclozolin
    Cynthia Wolf1,2, Barbara Abbott1, Gerald A. LeBlanc2, and L. Earl Gray, Jr.1
    1USEPA, ORD, NHEERL, RTD, RTP, NC 27711, 2NCSU, Environmental and Molecular Toxicology, Ral...

  3. SPECIES DIFFERENCES IN ANDROGEN AND ESTROGEN RECEPTOR STRUCTURE AND FUNCTION AMONG VERTEBRATES AND INVERTEBRATES: INTERSPECIES EXTRAPOLATIONS REGARDING ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Species Differences in Androgen and Estrogen Receptor Structure and Function Among Vertebrates and Invertebrates: Interspecies Extrapolations regarding Endocrine Disrupting Chemicals
    VS Wilson1, GT Ankley2, M Gooding 1,3, PD Reynolds 1,4, NC Noriega 1, M Cardon 1, P Hartig1,...

  4. BINDING OF STEROIDS AND ENVIRONMENTAL CHEMICALS TO THE RAINBOW TROUT ANDROGEN RECEPTOR ALPHA EXPRESSED IN COS CELLS

    EPA Science Inventory

    Binding of Steroids and Environmental Chemicals to the Rainbow Trout Androgen Receptor Alpha Expressed in COS Cells.

    Mary C. Cardon, L. Earl Gray. Jr., Phillip C. Hartig and Vickie S. Wilson
    U.S. Environmental Protection Agency, ORD, NHEERL, Reproductive Toxicology...

  5. Identification of Androgen Receptor Antagonists in Fish Using a Simple Bioassay with the Fathead Minnow Pimephales promelas .

    EPA Science Inventory

    Considerable effort has been expended on the development of bioassays to detect chemicals that affect endocrine function controlled by the vertebrate hypothalamic-pituitary-gonadal (HPG) axis via different mechanisms/modes of action (MOA). Antagonism of the androgen receptor (AR)...

  6. Androgen deprivation therapy sensitizes prostate cancer cells to T-cell killing through androgen receptor dependent modulation of the apoptotic pathway.

    PubMed

    Ardiani, Andressa; Gameiro, Sofia R; Kwilas, Anna R; Donahue, Renee N; Hodge, James W

    2014-10-15

    Despite recent advances in diagnosis and management, prostrate cancer remains the second most common cause of death from cancer in American men, after lung cancer. Failure of chemotherapies and hormone-deprivation therapies is the major cause of death in patients with castration-resistant prostate cancer (CRPC). Currently, the androgen inhibitors enzalutamide and abiraterone are approved for treatment of metastatic CRPC. Here we show for the first time that both enzalutamide and abiraterone render prostate tumor cells more sensitive to T cell-mediated lysis through immunogenic modulation, and that these immunomodulatory activities are androgen receptor (AR)-dependent. In studies reported here, the NAIP gene was significantly down-regulated in human prostate tumor cells treated in vitro and in vivo with enzalutamide. Functional analysis revealed that NAIP played a critical role in inducing CTL sensitivity. Amplification of AR is a major mechanism of resistance to androgen-deprivation therapy (ADT). Here, we show that enzalutamide enhances sensitivity to immune-mediated killing of prostate tumor cells that overexpress AR. The immunomodulatory properties of enzalutamide and abiraterone provide a rationale for their use in combination with immunotherapeutic agents in CRPC, especially for patients with minimal response to enzalutamide or abiraterone alone, or for patients who have developed resistance to ADT. PMID:25344864

  7. A Recurrent Germline Mutation in the 5’UTR of the Androgen Receptor Causes Complete Androgen Insensitivity by Activating Aberrant uORF Translation

    PubMed Central

    Hornig, Nadine C.; de Beaufort, Carine; Denzer, Friederike; Cools, Martine; Wabitsch, Martin; Ukat, Martin; Kulle, Alexandra E.; Schweikert, Hans-Udo; Werner, Ralf; Hiort, Olaf; Audi, Laura; Siebert, Reiner; Ammerpohl, Ole; Holterhus, Paul-Martin

    2016-01-01

    A subset of patients with monogenic disorders lacks disease causing mutations in the protein coding region of the corresponding gene. Here we describe a recurrent germline mutation found in two unrelated patients with complete androgen insensitivity syndrome (CAIS) generating an upstream open reading frame (uORF) in the 5’ untranslated region (5’-UTR) of the androgen receptor (AR) gene. We show in patient derived primary genital skin fibroblasts as well as in cell-based reporter assays that this mutation severely impacts AR function by reducing AR protein levels without affecting AR mRNA levels. Importantly, the newly generated uORF translates into a polypeptide and the expression level of this polypeptide inversely correlates with protein translation from the primary ORF of the AR thereby providing a model for AR-5′UTR mediated translational repression. Our findings not only add a hitherto unrecognized genetic cause to complete androgen insensitivity but also underline the importance of 5′UTR mutations affecting uORFs for the pathogenesis of monogenic disorders in general. PMID:27110943

  8. A Recurrent Germline Mutation in the 5'UTR of the Androgen Receptor Causes Complete Androgen Insensitivity by Activating Aberrant uORF Translation.

    PubMed

    Hornig, Nadine C; de Beaufort, Carine; Denzer, Friederike; Cools, Martine; Wabitsch, Martin; Ukat, Martin; Kulle, Alexandra E; Schweikert, Hans-Udo; Werner, Ralf; Hiort, Olaf; Audi, Laura; Siebert, Reiner; Ammerpohl, Ole; Holterhus, Paul-Martin

    2016-01-01

    A subset of patients with monogenic disorders lacks disease causing mutations in the protein coding region of the corresponding gene. Here we describe a recurrent germline mutation found in two unrelated patients with complete androgen insensitivity syndrome (CAIS) generating an upstream open reading frame (uORF) in the 5' untranslated region (5'-UTR) of the androgen receptor (AR) gene. We show in patient derived primary genital skin fibroblasts as well as in cell-based reporter assays that this mutation severely impacts AR function by reducing AR protein levels without affecting AR mRNA levels. Importantly, the newly generated uORF translates into a polypeptide and the expression level of this polypeptide inversely correlates with protein translation from the primary ORF of the AR thereby providing a model for AR-5'UTR mediated translational repression. Our findings not only add a hitherto unrecognized genetic cause to complete androgen insensitivity but also underline the importance of 5'UTR mutations affecting uORFs for the pathogenesis of monogenic disorders in general. PMID:27110943

  9. Androgen receptors in brain and pituitary of female rats: cyclic changes and comparisons with the male.

    PubMed

    Handa, R J; Reid, D L; Resko, J A

    1986-03-01

    The in vitro binding of a synthetic androgen, methyltrienolone ([3H]-R1881), to brain and pituitary (PIT) cytosol and nuclear extracts was determined in male and female rats. Purified cytosol was prepared from PIT or hypothalamic-preoptic area-amygdala (HPA) and incubated in the presence of 0.1 to 10 nM [3H]-R1881. Scatchard analysis revealed the presence of a single, saturable, high-affinity binding site in PIT cytosol with a dissociation constant (Kd) of 0.42 X 10(-10) M in females and 0.95 X 10(-10) M in intact males. The Kd of HPA cytosol was much less in castrated males [0.47 +/- 0.05 (SEM) X 10(-10)M, n = 7] and females (0.63 +/- 0.1 X 10(-10) M, n = 4) than in intact males (5.8 +/- 1.1 X 10(-10) M, n = 8). Treatment of castrated males with dihydrotestosterone (DHT) for 24 h (250 micrograms/100 g of body weight) increased the Kd of HPA cytosol only slightly (1.6 X 10(-10) M, mean of two replicates). Scatchard analysis of salt-extracted nuclear androgen receptor (ARn) showed a single, high-affinity binding site with similar Kd values in PIT and HPA of intact and castrated, DHT-treated male rats (PIT Kd = 7.3 X 10(-10) M, 9.3 X 10(-10) M; HPA Kd = 1.5 X 10(-9) M, 1.3 X 10(-9) M, respectively). Competition studies involving a range of several radioinert steroids revealed that the binding of [3H]-R1881 to cytosol (ARc) and nuclear extract was specific for androgen receptor when triamcinolone acetonide (10 microM) was added. The ARc and ARn levels were quantified in PIT, preoptic area (POA), hypothalamus (HT), amygdala, hippocampus, and cortex by single point estimation. Significantly (p less than 0.01) greater amounts of ARc were detected in PIT of ovariectomized females (32.7 +/- 2.9 fmol/mg of protein) than in that of orchidectomized males (22.33 +/- 1.6 fmol/mg of protein). The highest levels in the brain were seen in HT and POA. Pituitary ARc in females varied throughout the estrous cycle. Significantly (p less than 0.01) greater amounts were detected on

  10. Racial Variations in Prostate Cancer Molecular Subtypes and Androgen Receptor Signaling Reflect Anatomic Tumor Location

    PubMed Central

    Faisal, Farzana A.; Sundi, Debasish; Tosoian, Jeffrey J.; Choeurng, Voleak; Alshalalfa, Mohammed; Ross, Ashley E.; Klein, Eric; Den, Robert; Dicker, Adam; Erho, Nicholas; Davicioni, Elai; Lotan, Tamara L.; Schaeffer, Edward M.

    2016-01-01

    Prostate cancer (PCa) subtypes based on ETS gene expression have been described. Recent studies suggest there are racial differences in tumor location, with PCa located anteriorly more often among African-American (AA) compared to Caucasian-American (CA) men. In this retrospective analysis of a multi-institutional cohort treated by radical prostatectomy (179 CA, 121 AA), we evaluated associations among molecular subtype, race, anatomic tumor location, and androgen receptor (AR) signaling. Subtype (m-ERG+, m-ETS+, m-SPINK1+, or triple-negative) was determined using distribution-based outlier analysis. AR signaling was investigated using gene expression profiling of canonical AR targets. m-ERG+ was more common in CA than AA men (47% vs 22%, p < 0.001). AA men were more likely to be m-SPINK1+ (13% vs 7%; p = 0.069) and triple-negative (50% vs 37%; p = 0.043). Racial differences in molecular subtypes did not persist when tumors were analyzed by location, suggesting a biologically important relationship between tumor location and subtype. Accordingly, anterior tumor location was associated with higher Decipher scores and lower global AR signaling. Patient summary This study demonstrates associations among patient race, prostate cancer molecular subtypes, and tumor location. Location-specific differences in androgen regulation may further underlie these relationships. PMID:26443432

  11. Myoglobin expression in prostate cancer is correlated to androgen receptor expression and markers of tumor hypoxia.

    PubMed

    Meller, Sebastian; Bicker, Anne; Montani, Matteo; Ikenberg, Kristian; Rostamzadeh, Babak; Sailer, Verena; Wild, Peter; Dietrich, Dimo; Uhl, Barbara; Sulser, Tullio; Moch, Holger; Gorr, Thomas A; Stephan, Carsten; Jung, Klaus; Hankeln, Thomas; Kristiansen, Glen

    2014-10-01

    Recent studies identified unexpected expression and transcriptional complexity of the hemoprotein myoglobin (MB) in human breast cancer but its role in prostate cancer is still unclear. Expression of MB was immunohistochemically analyzed in three independent cohorts of radical prostatectomy specimens (n = 409, n = 625, and n = 237). MB expression data were correlated with clinicopathological parameters and molecular parameters of androgen and hypoxia signaling. Expression levels of novel tumor-associated MB transcript variants and the VEGF gene as a hypoxia marker were analyzed using qRT-PCR. Fifty-three percent of the prostate cancer cases were MB positive and significantly correlated with androgen receptor (AR) expression (p < 0.001). The positive correlation with CAIX (p < 0.001) and FASN (p = 0.008) as well as the paralleled increased expression of the tumor-associated MB transcript variants and VEGF suggest that hypoxia participates in MB expression regulation. Analogous to breast cancer, MB expression in prostate cancer is associated with steroid hormone signaling and markers of hypoxia. Further studies must elucidate the novel functional roles of MB in human carcinomas, which probably extend beyond its classic intramuscular function in oxygen storage. PMID:25172328

  12. CAMK2N1 inhibits prostate cancer progression through androgen receptor-dependent signaling.

    PubMed

    Wang, Tao; Guo, Shuiming; Liu, Zhuo; Wu, Licheng; Li, Mingchao; Yang, Jun; Chen, Ruibao; Liu, Xiaming; Xu, Hua; Cai, Shaoxin; Chen, Hui; Li, Weiyong; Xu, Shaohua; Wang, Liang; Hu, Zhiquan; Zhuang, Qianyuan; Wang, Liping; Wu, Kongming; Liu, Jihong; Ye, Zhangqun; Ji, Jun-Yuan; Wang, Chenguang; Chen, Ke

    2014-11-15

    Castration resistance is a major obstacle to hormonal therapy for prostate cancer patients. Although androgen independence of prostate cancer growth is a known contributing factor to endocrine resistance, the mechanism of androgen receptor deregulation in endocrine resistance is still poorly understood. Herein, the CAMK2N1 was shown to contribute to the human prostate cancer cell growth and survival through AR-dependent signaling. Reduced expression of CAMK2N1 was correlated to recurrence-free survival of prostate cancer patients with high levels of AR expression in their tumor. CAMK2N1 and AR signaling form an auto-regulatory negative feedback loop: CAMK2N1 expression was down-regulated by AR activation; while CAMK2N1 inhibited AR expression and transactivation through CAMKII and AKT pathways. Knockdown of CAMK2N1 in prostate cancer cells alleviated Casodex inhibition of cell growth, while re-expression of CAMK2N1 in castration-resistant cells sensitized the cells to Casodex treatment. Taken together, our findings suggest that CAMK2N1 plays a tumor suppressive role and serves as a crucial determinant of the resistance of prostate cancer to endocrine therapies. PMID:25296973

  13. Molecular and structural basis of androgen receptor responses to dihydrotestosterone, medroxyprogesterone acetate and Δ(4)-tibolone.

    PubMed

    Bianco-Miotto, Tina; Trotta, Andrew P; Need, Eleanor F; Lee, Alice M C; Ochnik, Aleksandra M; Giorgio, Lauren; Leach, Damien A; Swinstead, Erin E; O'Loughlin, Melissa A; Newman, Michelle R; Birrell, Stephen N; Butler, Lisa M; Harris, Jonathan M; Buchanan, Grant

    2014-02-15

    Medroxyprogesterone acetate (MPA) has widely been used in hormone replacement therapy (HRT), and is associated with an increased risk of breast cancer, possibly due to disruption of androgen receptor (AR) signaling. In contrast, the synthetic HRT Tibolone does not increase breast density, and is rapidly metabolized to estrogenic 3α-OH-tibolone and 3β-OH-tibolone, and a delta-4 isomer (Δ(4)-TIB) that has both androgenic and progestagenic properties. Here, we show that 5α-dihydrotestosterone (DHT) and Δ(4)-TIB, but not MPA, stabilize AR protein levels, initiate specific AR intramolecular interactions critical for AR transcriptional regulation, and increase proliferation of AR positive MDA-MB-453 breast cancer cells. Structural modeling and molecular dynamic simulation indicate that Δ(4)-TIB induces a more stable AR structure than does DHT, and MPA a less stable one. Microarray expression analyses confirms that the molecular actions of Δ(4)-TIB more closely resembles DHT in breast cancer cells than either ligand does to MPA. PMID:24239616

  14. Peripheral androgen receptor gene suppression rescues disease in mouse models of spinal and bulbar muscular atrophy.

    PubMed

    Lieberman, Andrew P; Yu, Zhigang; Murray, Sue; Peralta, Raechel; Low, Audrey; Guo, Shuling; Yu, Xing Xian; Cortes, Constanza J; Bennett, C Frank; Monia, Brett P; La Spada, Albert R; Hung, Gene

    2014-05-01

    Spinal and bulbar muscular atrophy (SBMA) is caused by the polyglutamine androgen receptor (polyQ-AR), a protein expressed by both lower motor neurons and skeletal muscle. Although viewed as a motor neuronopathy, data from patients and mouse models suggest that muscle contributes to disease pathogenesis. Here, we tested this hypothesis using AR113Q knockin and human bacterial artificial chromosome/clone (BAC) transgenic mice that express the full-length polyQ-AR and display androgen-dependent weakness, muscle atrophy, and early death. We developed antisense oligonucleotides that suppressed AR gene expression in the periphery but not the CNS after subcutaneous administration. Suppression of polyQ-AR in the periphery rescued deficits in muscle weight, fiber size, and grip strength, reversed changes in muscle gene expression, and extended the lifespan of mutant males. We conclude that polyQ-AR expression in the periphery is an important contributor to pathology in SBMA mice and that peripheral administration of therapeutics should be explored for SBMA patients. PMID:24746732

  15. Potent anti-prostate cancer agents derived from a novel androgen receptor down-regulating agent.

    PubMed

    Purushottamachar, Puranik; Khandelwal, Aakanksha; Vasaitis, Tadas S; Bruno, Robert D; Gediya, Lalji K; Njar, Vincent C O

    2008-04-01

    The search for novel androgen receptor (AR) down-regulating agents by catalyst HipHop pharmacophore modeling led to the discovery of some lead molecules. Unexpectedly, the effect of these leads on human prostate cancer LNCaP cell viability did not correlate with the ability of the compounds to cause down-regulation of AR protein expression. Through rational synthetic optimization of the lead compound (BTB01434), we have discovered a series of novel substituted diaryl molecules as potent anti-prostate cancer agents. Some compounds (1-6) were shown to be extremely potent inhibitors of LNCaP cell viability with GI(50) values in the nanomolar range (1.45-83 nM). The most potent compound (4-methylphenyl)[(4-methylphenyl)sulfonyl]amine (5) with a GI(50) value of 1.45 nM is 27,000 times more potent than our lead compound BTB01434 (GI(50)=39.8 microM). In addition, some of the compounds exhibited modest anti-androgenic activities and one was also a potent inhibitor (GI(50)=850 nM) of PC-3 (AR-null) cell growth. A clear structure-activity relationship (SAR) has been established for activity against LNCaP cells, where potent molecules possess two substituted/unsubstituted aromatic rings connected through a sulfonamide linker. These novel compounds are strong candidates for development for the treatment of hormone-sensitive and importantly hormone-refractory prostate cancers in humans. PMID:18316193

  16. Oestradiol metabolism and androgen receptor genotypes are associated with right ventricular function

    PubMed Central

    Ventetuolo, Corey E.; Mitra, Nandita; Wan, Fei; Manichaikul, Ani; Barr, R. Graham; Johnson, Craig; Bluemke, David A.; Lima, Joao A.C.; Tandri, Hari; Ouyang, Pamela; Kawut, Steven M.

    2016-01-01

    Sex hormones are linked to right ventricular (RV) function, but the relationship between genetic variation in these pathways and RV function is unknown. We performed a cross-sectional study of 2761 genotyped adults without cardiovascular disease. The relationships between RV measures and single nucleotide polymorphisms (SNPs) in 10 candidate genes were assessed. Urinary oestradiol (E2) metabolites produced by cytochrome P4501B1 (CYP1B1) and serum testosterone were measured in women and men respectively. In African-American (AA) women, the CYP1B1 SNP rs162561 was associated with RV ejection fraction (RVEF), such that each copy of the A allele was associated with a 2.0% increase in RVEF. Haplotype analysis revealed associations with RVEF in AA (global p<7.2×10−6) and white (global p=0.05) women. In white subjects, higher E2 metabolite levels were associated with significantly higher RVEF. In men, androgen receptors SNPs (rs1337080; rs5918764) were significantly associated with all RV measures and modified the relationship between testosterone and RVEF. Genetic variation in E2 metabolism and androgen signalling was associated with RV morphology in a sex-specific manner. The CYP1B1 SNP identified is in tight linkage disequilibrium with SNPs associated with pulmonary hypertension and oncogenesis, suggesting these pathways may underpin sexual dimorphism in RV failure. PMID:26647441

  17. Oestradiol metabolism and androgen receptor genotypes are associated with right ventricular function.

    PubMed

    Ventetuolo, Corey E; Mitra, Nandita; Wan, Fei; Manichaikul, Ani; Barr, R Graham; Johnson, Craig; Bluemke, David A; Lima, Joao A C; Tandri, Hari; Ouyang, Pamela; Kawut, Steven M

    2016-02-01

    Sex hormones are linked to right ventricular (RV) function, but the relationship between genetic variation in these pathways and RV function is unknown.We performed a cross-sectional study of 2761 genotyped adults without cardiovascular disease. The relationships between RV measures and single nucleotide polymorphisms (SNPs) in 10 candidate genes were assessed. Urinary oestradiol (E2) metabolites produced by cytochrome P4501B1 (CYP1B1) and serum testosterone were measured in women and men respectively.In African-American (AA) women, the CYP1B1 SNP rs162561 was associated with RV ejection fraction (RVEF), such that each copy of the A allele was associated with a 2.0% increase in RVEF. Haplotype analysis revealed associations with RVEF in AA (global p<7.2×10(-6)) and white (global p=0.05) women. In white subjects, higher E2 metabolite levels were associated with significantly higher RVEF. In men, androgen receptors SNPs (rs1337080; rs5918764) were significantly associated with all RV measures and modified the relationship between testosterone and RVEF.Genetic variation in E2 metabolism and androgen signalling was associated with RV morphology in a sex-specific manner. The CYP1B1 SNP identified is in tight linkage disequilibrium with SNPs associated with pulmonary hypertension and oncogenesis, suggesting these pathways may underpin sexual dimorphism in RV failure. PMID:26647441

  18. Transient receptor potential melastatin 4 channel contributes to migration of androgen-insensitive prostate cancer cells

    PubMed Central

    Kilch, Tatiana; Jochum, Marcus Martin; Urban, Sabine Katharina; Jung, Volker; Stöckle, Michael; Rother, Karen; Greiner, Markus; Peinelt, Christine

    2015-01-01

    Impaired Ca2+ signaling in prostate cancer contributes to several cancer hallmarks, such as enhanced proliferation and migration and a decreased ability to induce apoptosis. Na+ influx via transient receptor potential melastatin 4 channel (TRPM4) can reduce store-operated Ca2+ entry (SOCE) by decreasing the driving force for Ca2+. In patients with prostate cancer, gene expression of TRPM4 is elevated. Recently, TRPM4 was identified as a cancer driver gene in androgen-insensitive prostate cancer. We investigated TRPM4 protein expression in cancer tissue samples from 20 patients with prostate cancer. We found elevated TRPM4 protein levels in prostatic intraepithelial neoplasia (PIN) and prostate cancer tissue compared to healthy tissue. In primary human prostate epithelial cells (hPEC) from healthy tissue and in the androgen-insensitive prostate cancer cell lines DU145 and PC3, TRPM4 mediated large Na+ currents. We demonstrated significantly increased SOCE after siRNA targeting of TRPM4 in hPEC and DU145 cells. In addition, knockdown of TRPM4 reduced migration but not proliferation of DU145 and PC3 cells. Taken together, our data identify TRPM4 as a regulator of SOCE in hPEC and DU145 cells, demonstrate a role for TRPM4 in cancer cell migration and suggest that TRPM4 is a promising potential therapeutic target. PMID:26496025

  19. Abiraterone Treatment in Castration-Resistant Prostate Cancer Selects for Progesterone Responsive Mutant Androgen Receptors

    PubMed Central

    Chen, Eddy J.; Sowalsky, Adam G.; Gao, Shuai; Cai, Changmeng; Voznesensky, Olga; Schaefer, Rachel; Loda, Massimo; True, Lawrence D.; Ye, Huihui; Troncoso, Patricia; Lis, Rosina L.; Kantoff, Philip W.; Montgomery, Robert B.; Nelson, Peter S.; Bubley, Glenn J.; Balk, Steven P.; Taplin, Mary-Ellen

    2014-01-01

    Purpose The CYP17A1 inhibitor abiraterone markedly reduces androgen precursors and is thereby effective in castration-resistant prostate cancer (CRPC). However, abiraterone increases progesterone, which can activate certain mutant androgen receptors (ARs) identified previously in flutamide-resistant tumors. Therefore, we sought to determine if CYP17A1 inhibitor treatment selects for progesterone activated mutant ARs. Experimental Design AR was examined by targeted sequencing in metastatic tumor biopsies from 18 CRPC patients who were progressing on a CYP17A1 inhibitor (17 on abiraterone, 1 on ketoconazole), alone or in combination with dutasteride, and by whole exome sequencing in residual tumor in one patient treated with neoadjuvant leuprolide plus abiraterone. Results The progesterone-activated T878A mutant AR was present at high allele frequency in 3 of the 18 CRPC cases. It was also present in one focus of resistant tumor in the neoadjuvant treated patient, but not in a second clonally related resistant focus which instead had lost one copy of PTEN and both copies of CHD1. The T878A mutation appeared to be less common in the subset of CRPC patients treated with abiraterone plus dutasteride, and transfection studies showed that dutasteride was a more potent direct antagonist of the T878A versus the wildtype AR. Conclusions These findings indicate that selection for tumor cells expressing progesterone-activated mutant ARs is a mechanism of resistance to CYP17A1 inhibition. PMID:25320358

  20. Differential expression of androgen, estrogen, and progesterone receptors in benign prostatic hyperplasia

    PubMed Central

    Song, Lingmin; Shen, Wenhao; Zhang, Heng; Wang, Qiwu; Wang, Yongquan; Zhou, Zhansong

    2016-01-01

    This study aimed to identify the differential expression levels of androgen receptor (AR), estrogen receptors (ERα, ERβ), and progesterone receptor (PGR) between normal prostate and benign prostatic hyperplasia (BPH). The combination of immunohistochemistry, quantitative real-time reverse transcription polymerase chain reaction, and Western blotting assay was used to identify the distribution and differential expression of these receptors at the immunoactive biomarker, transcriptional, and protein levels between 5 normal human prostate tissues and 40 BPH tissues. The results were then validated in a rat model of BPH induced by testosterone propionate and estradiol benzoate. In both human and rat prostate tissues, AR was localized mainly to epithelial and stromal cell nuclei; ERα was distributed mainly to stromal cells, but not exclusively; ERβ was interspersed in the basal layer of epithelium, but sporadically in epithelial and stromal cells; PGR was expressed abundantly in cytoplasm of epithelial and stromal cells. There were decreased expression of ERα and increased expression of PGR, but no difference in the expression of ERβ in the BPH compared to the normal prostate of both human and rat. Increased expression of AR in the BPH compared to the normal prostate of human was observed, however, the expression of AR in the rat prostate tissue was decreased. This study identified the activation of AR and PGR and repression of ERα in BPH, which indicate a promoting role of AR and PGR and an inhibitory role of ERα in the pathogenesis of BPH.

  1. A role for the androgen receptor in the treatment of male breast cancer.

    PubMed

    Zhu, Jason; Davis, Carter T; Silberman, Sandra; Spector, Neil; Zhang, Tian

    2016-02-01

    Male breast cancer (BC) is relatively rare, making up less than 1% of all breast cancer cases in the United States. Treatment guidelines for male BC are derived from studies on the treatment of female BC, and are based molecular and clinical characteristics, such as hormone receptor positivity. For female estrogen receptor positive (ER+) breast cancers, the standard of care includes three classes of endocrine therapies: selective estrogen receptor modulators, aromatase inhibitors, and pure anti-estrogens. In contrast to female ER+ breast cancers, there is less known about the optimal treatment for male ER+ BC. Furthermore, in contrast to ER, less is known about the role of the androgen receptor (AR) in male and female BC. We report here the treatment of a 28-year-old man with metastatic AR+, ER+ breast cancer otherwise refractory to chemotherapy, who has had a durable clinical response to hormonal suppression with the combination of aromatase inhibition (Letrozole) in conjunction with a GnRH agonist (Leuprolide). PMID:26669267

  2. Soluble androgen receptor oligomers underlie pathology in a mouse model of spinobulbar muscular atrophy.

    PubMed

    Li, Mei; Chevalier-Larsen, Erica S; Merry, Diane E; Diamond, Marc I

    2007-02-01

    In polyglutamine diseases such as X-linked spinobulbar muscular atrophy (SBMA), it is unknown whether the toxic form of the protein is an insoluble or soluble aggregate or a monomer. We have addressed this question by studying a full-length androgen receptor (AR) mouse model of SBMA. We used biochemistry and atomic force microscopy to immunopurify oligomers soluble after ultracentrifugation that are comprised of a single approximately 50-kDa N-terminal polyglutamine-containing AR fragment. AR oligomers appeared several weeks prior to symptom onset, were distinct and temporally dissociated from intranuclear inclusions, and disappeared rapidly after castration, which halts disease. This is the first demonstration of soluble AR oligomers in vivo and suggests that they underlie neurodegeneration in SBMA. PMID:17121819

  3. The androgen receptor and genetic susceptibility to ovarian cancer: results from a case series.

    PubMed

    Levine, D A; Boyd, J

    2001-02-01

    Our objectives were to test whether polymorphic variation in the (CAG)n repeat of the androgen receptor (AR) gene affects penetrance of germ-line BRCA mutations for ovarian cancer or age of diagnosis for ovarian cancer. Using a case-series study design, 179 consecutive Ashkenazi Jewish ovarian cancer patients were genotyped for AR repeat length and BRCA mutation status. There was no association between AR repeat length and presence of a BRCA mutation. However, ovarian cancer patients from both groups (with or without BRCA mutation) who carried a short AR allele were diagnosed an average of 7.2 (95% confidence interval, 2.3-12.1) years earlier than patients who did not carry a short allele (P = 0.004). These data suggest that AR allele length affects age of diagnosis of ovarian cancer, irrespective of BRCA mutation status. PMID:11221880

  4. Agonist and antagonist switch DNA motifs recognized by human androgen receptor in prostate cancer

    PubMed Central

    Chen, Zhong; Lan, Xun; Thomas-Ahner, Jennifer M; Wu, Dayong; Liu, Xiangtao; Ye, Zhenqing; Wang, Liguo; Sunkel, Benjamin; Grenade, Cassandra; Chen, Junsheng; Zynger, Debra L; Yan, Pearlly S; Huang, Jiaoti; Nephew, Kenneth P; Huang, Tim H-M; Lin, Shili; Clinton, Steven K; Li, Wei; Jin, Victor X; Wang, Qianben

    2015-01-01

    Human transcription factors recognize specific DNA sequence motifs to regulate transcription. It is unknown whether a single transcription factor is able to bind to distinctly different motifs on chromatin, and if so, what determines the usage of specific motifs. By using a motif-resolution chromatin immunoprecipitation-exonuclease (ChIP-exo) approach, we find that agonist-liganded human androgen receptor (AR) and antagonist-liganded AR bind to two distinctly different motifs, leading to distinct transcriptional outcomes in prostate cancer cells. Further analysis on clinical prostate tissues reveals that the binding of AR to these two distinct motifs is involved in prostate carcinogenesis. Together, these results suggest that unique ligands may switch DNA motifs recognized by ligand-dependent transcription factors in vivo. Our findings also provide a broad mechanistic foundation for understanding ligand-specific induction of gene expression profiles. PMID:25535248

  5. Agonist and antagonist switch DNA motifs recognized by human androgen receptor in prostate cancer.

    PubMed

    Chen, Zhong; Lan, Xun; Thomas-Ahner, Jennifer M; Wu, Dayong; Liu, Xiangtao; Ye, Zhenqing; Wang, Liguo; Sunkel, Benjamin; Grenade, Cassandra; Chen, Junsheng; Zynger, Debra L; Yan, Pearlly S; Huang, Jiaoti; Nephew, Kenneth P; Huang, Tim H-M; Lin, Shili; Clinton, Steven K; Li, Wei; Jin, Victor X; Wang, Qianben

    2015-02-12

    Human transcription factors recognize specific DNA sequence motifs to regulate transcription. It is unknown whether a single transcription factor is able to bind to distinctly different motifs on chromatin, and if so, what determines the usage of specific motifs. By using a motif-resolution chromatin immunoprecipitation-exonuclease (ChIP-exo) approach, we find that agonist-liganded human androgen receptor (AR) and antagonist-liganded AR bind to two distinctly different motifs, leading to distinct transcriptional outcomes in prostate cancer cells. Further analysis on clinical prostate tissues reveals that the binding of AR to these two distinct motifs is involved in prostate carcinogenesis. Together, these results suggest that unique ligands may switch DNA motifs recognized by ligand-dependent transcription factors in vivo. Our findings also provide a broad mechanistic foundation for understanding ligand-specific induction of gene expression profiles. PMID:25535248

  6. CACUL1 functions as a negative regulator of androgen receptor in prostate cancer cells.

    PubMed

    Choi, Hanbyeul; Lee, Sang Hyup; Um, Soo-Jong; Kim, Eun-Joo

    2016-07-01

    The androgen receptor (AR) plays a critical role in the initiation and progression of prostate cancer (PCa), and thus its regulation is an important tool in PCa therapy. Here, we report that CDK2-associated cullin 1 (CACUL1) directly associates with AR and suppresses AR transcriptional activity. In addition, CACUL1 represses histone demethylase LSD1-mediated AR transactivation by competing with LSD1 for AR binding. Depletion of CACUL1 enhances the LSD1 occupancy of the AR-target promoter, accompanied by decreased accumulation of H3K9me2, a repressive transcriptional marker. CACUL1 and LSD1 oppositely regulate CDX-induced cell death in AR-positive LNCaP and metastatic castrate-resistant LNCaP-LN3 cells. These data suggest that CACUL1 impairs LSD1-mediated activation of AR, thereby implicating it as a potential antitumor target in PCa. PMID:27085459

  7. ERG signaling in prostate cancer is driven through PRMT5-dependent methylation of the Androgen Receptor.

    PubMed

    Mounir, Zineb; Korn, Joshua M; Westerling, Thomas; Lin, Fallon; Kirby, Christina A; Schirle, Markus; McAllister, Gregg; Hoffman, Greg; Ramadan, Nadire; Hartung, Anke; Feng, Yan; Kipp, David Randal; Quinn, Christopher; Fodor, Michelle; Baird, Jason; Schoumacher, Marie; Meyer, Ronald; Deeds, James; Buchwalter, Gilles; Stams, Travis; Keen, Nicholas; Sellers, William R; Brown, Myles; Pagliarini, Raymond A

    2016-01-01

    The TMPRSS2:ERG gene fusion is common in androgen receptor (AR) positive prostate cancers, yet its function remains poorly understood. From a screen for functionally relevant ERG interactors, we identify the arginine methyltransferase PRMT5. ERG recruits PRMT5 to AR-target genes, where PRMT5 methylates AR on arginine 761. This attenuates AR recruitment and transcription of genes expressed in differentiated prostate epithelium. The AR-inhibitory function of PRMT5 is restricted to TMPRSS2:ERG-positive prostate cancer cells. Mutation of this methylation site on AR results in a transcriptionally hyperactive AR, suggesting that the proliferative effects of ERG and PRMT5 are mediated through attenuating AR's ability to induce genes normally involved in lineage differentiation. This provides a rationale for targeting PRMT5 in TMPRSS2:ERG positive prostate cancers. Moreover, methylation of AR at arginine 761 highlights a mechanism for how the ERG oncogene may coax AR towards inducing proliferation versus differentiation. PMID:27183006

  8. CSF1 Receptor Targeting In Prostate Cancer Reverses Macrophage-Mediated Resistance To Androgen Blockade Therapy

    PubMed Central

    Escamilla, Jemima; Schokrpur, Shiruyeh; Liu, Connie; Priceman, Saul J.; Moughon, Diana; Jiang, Ziyue; Pouliot, Frederic; Magyar, Clara; Sung, James L.; Xu, Jingying; Deng, Gang; West, Brian L.; Bollag, Gideon; Fradet, Yves; Lacombe, Louis; Jung, Michael E.; Huang, Jiaoti; Wu, Lily

    2015-01-01

    Growing evidence suggests that tumor-associated macrophages (TAMs) promote cancer progression and therapeutic resistance by enhancing angiogenesis, matrix-remodeling and immunosuppression. In this study prostate cancer (PCa) under androgen blockade therapy (ABT) was investigated, demonstrating that TAMs contribute to PCa disease recurrence through paracrine signaling processes. ABT induced the tumor cells to express macrophage colony-stimulating factor 1 (M-CSF-1 or CSF-1) and other cytokines that recruit and modulate macrophages, causing a significant increase in TAM infiltration. Inhibitors of CSF-1 signaling through its receptor, CSF-1R, were tested in combination with ABT, demonstrating that blockade of TAM influx in this setting disrupts tumor promotion and sustains a more durable therapeutic response compared to ABT alone. PMID:25736687

  9. Importance of Breast Cancer Subtype in the Development of Androgen Receptor Directed Therapy

    PubMed Central

    Lim, Elgene; Ni, Min; Cao, Shiliang; Hazra, Aditi; Tamimi, Rulla M.; Brown, Myles

    2014-01-01

    The androgen receptor (AR) has re-emerged as a potential therapeutic target in breast cancer. This stems from recent progress made in preclinical models, that have recognized important differences in the effect of AR expression on patient outcomes among different breast cancer subtypes. In parallel, the clinical development of new generations of AR directed therapies for prostate cancer has begun to mature. The availability of these new agents has translated into new trials to treat breast cancer. It is critical that studies of the effect of AR expression and signaling in breast cancer be context and subtype specific in order to successfully target AR signalling as a therapeutic strategy for breast cancer. We will review developments in preclinical studies, and recent clinical trials targeting AR in breast cancer. PMID:24860642

  10. The androgen receptor cistrome is extensively reprogrammed in human prostate tumorigenesis

    PubMed Central

    Pomerantz, Mark M.; Li, Fugen; Takeda, David; Lenci, Romina; Chonkar, Apurva; Chabot, Matthew; Cejas, Paloma; Vazquez, Francisca; Cook, Jennifer; Shivdasani, Ramesh A.; Bowden, Michaela; Lis, Rosina; Hahn, William C.; Kantoff, Philip W.; Brown, Myles; Loda, Massimo; Long, Henry W.; Freedman, Matthew L.

    2015-01-01

    Master transcription factors interact with DNA to establish cell-type identity and to regulate gene expression in mammalian cells1,2. The genome-wide map of these transcription factor binding sites has been termed the cistrome3. Here we show that the androgen receptor (AR) cistrome undergoes extensive reprogramming during prostate epithelial transformation in man. Using human prostate tissue, we observed a core set of AR binding sites that are consistently reprogrammed in tumors. FOXA1 and HOXB13, co-localized with the reprogrammed AR sites in human tumor tissue. Introduction of FOXA1 and HOXB13 into an immortalized prostate cell line reprogrammed the AR cistrome to resemble that of a prostate tumor, functionally linking these specific factors to AR reprogramming. These findings offer mechanistic insights into a key set of events that drive normal prostate epithelium towards transformation and establish the centrality of epigenetic reprogramming in human prostate tumorigenesis. PMID:26457646

  11. Androgen Receptor Gene Polymorphism, Aggression, and Reproduction in Tanzanian Foragers and Pastoralists

    PubMed Central

    Butovskaya, Marina L.; Lazebny, Oleg E.; Vasilyev, Vasiliy A.; Dronova, Daria A.; Karelin, Dmitri V.; Mabulla, Audax Z. P.; Shibalev, Dmitri V.; Shackelford, Todd K.; Fink, Bernhard; Ryskov, Alexey P.

    2015-01-01

    The androgen receptor (AR) gene polymorphism in humans is linked to aggression and may also be linked to reproduction. Here we report associations between AR gene polymorphism and aggression and reproduction in two small-scale societies in northern Tanzania (Africa)—the Hadza (monogamous foragers) and the Datoga (polygynous pastoralists). We secured self-reports of aggression and assessed genetic polymorphism of the number of CAG repeats for the AR gene for 210 Hadza men and 229 Datoga men (aged 17–70 years). We conducted structural equation modeling to identify links between AR gene polymorphism, aggression, and number of children born, and included age and ethnicity as covariates. Fewer AR CAG repeats predicted greater aggression, and Datoga men reported more aggression than did Hadza men. In addition, aggression mediated the identified negative relationship between CAG repeats and number of children born. PMID:26291982

  12. Emerging Mechanisms of Resistance to Androgen Receptor Inhibitors in Prostate Cancer

    PubMed Central

    Arora, Vivek K.

    2016-01-01

    Preface Over the past ten years, preclinical studies implicating sustained androgen receptor (AR) signaling as the primary driver of castration resistant prostate cancer (CRPC) led to the development of novel agents targeting the AR pathway that are now in widespread clinical use. These drugs prolong survival of patients with late stage prostate cancer but are not curative. In this review, we highlight emerging mechanisms of acquired resistance to these contemporary therapies, which fall into the three broad categories of restored AR signaling, AR bypass signaling and complete AR independence. This diverse spectrum of resistance mechanisms presents new challenges for long term disease control, which may be addressable through early use of combination therapies guided by recent insights from genomic landscape studies of CRPC. PMID:26563462

  13. The Androgen Receptor Antagonizes Wnt/β-Catenin Signaling in Epidermal Stem Cells

    PubMed Central

    Kretzschmar, Kai; Cottle, Denny L; Schweiger, Pawel J; Watt, Fiona M

    2015-01-01

    Activation of Wnt/β-catenin signaling in adult mouse epidermis leads to expansion of the stem cell compartment and redirects keratinocytes in the interfollicular epidermis and sebaceous glands (SGs) to differentiate along the hair follicle (HF) lineages. Here we demonstrate that during epidermal development and homeostasis there is reciprocal activation of the androgen receptor (AR) and β-catenin in cells of the HF bulb. AR activation reduced β-catenin-dependent transcription, blocked β-catenin-induced induction of HF growth, and prevented β-catenin-mediated conversion of SGs into HFs. Conversely, AR inhibition enhanced the effects of β-catenin activation, promoting HF proliferation and differentiation, culminating in the formation of benign HF tumors and a complete loss of SG identity. We conclude that AR signaling has a key role in epidermal stem cell fate selection by modulating responses to β-catenin in adult mouse skin. PMID:26121213

  14. Intracellular kinetics of the androgen receptor shown by multimodal Image Correlation Spectroscopy (mICS)

    PubMed Central

    Chiu, Chi-Li; Patsch, Katherin; Cutrale, Francesco; Soundararajan, Anjana; Agus, David B.; Fraser, Scott E.; Ruderman, Daniel

    2016-01-01

    The androgen receptor (AR) pathway plays a central role in prostate cancer (PCa) growth and progression and is a validated therapeutic target. In response to ligand binding AR translocates to the nucleus, though the molecular mechanism is not well understood. We therefore developed multimodal Image Correlation Spectroscopy (mICS) to measure anisotropic molecular motion across a live cell. We applied mICS to AR translocation dynamics to reveal its multimodal motion. By integrating fluorescence imaging methods we observed evidence for diffusion, confined movement, and binding of AR within both the cytoplasm and nucleus of PCa cells. Our findings suggest that in presence of cytoplasmic diffusion, the probability of AR crossing the nuclear membrane is an important factor in determining the AR distribution between cytoplasm and the nucleus, independent of functional microtubule transport. These findings may have implications for the future design of novel therapeutics targeting the AR pathway in PCa. PMID:26936218

  15. [The mechanism of progression without androgen receptor interaction in prostate cancer].

    PubMed

    Matsuyama, Hideyasu; Matsumoto, Hiroaki

    2016-01-01

    Recently, new generation androgen receptor (AK) targeted agents enzautamide or abiraterone etc.) has been clinically utilized in patients with castration-resistant prostate cancer (CRPC). However, metastatic CRPC has also AR-independent survival pathway which leads to lethal phenotype by either adaptation or clonal selection resistant mechanism after AR targeted therapy. There are many studies regarding the progression mechanisms without AR signal transduction, such as growth factor, anti-apoptotic factor, and PTEN/mTOR pathway and so on. Also, cancer microenvironment and cancer stem cell is a hot research area for CRPC. It is very important to repress both AR-dependent and -independent signaling pathway to improve the clinical outcome in CRPC patients. Application of the new technology, such as next generation sequencing, would be developing for the prostate cancer research, providing pre-clinical proof-of-principle as a promising approach in CRPC. PMID:26793881

  16. Enhancement of peripheral nerve regeneration due to treadmill training and electrical stimulation is dependent on androgen receptor signaling.

    PubMed

    Thompson, Nicholas J; Sengelaub, Dale R; English, Arthur W

    2014-05-01

    Moderate exercise in the form of treadmill training and brief electrical nerve stimulation both enhance axon regeneration after peripheral nerve injury. Different regimens of exercise are required to enhance axon regeneration in male and female mice (Wood et al.: Dev Neurobiol 72 (2012) 688-698), and androgens are suspected to be involved. We treated mice with the androgen receptor blocker, flutamide, during either exercise or electrical stimulation, to evaluate the role of androgen receptor signaling in these activity-based methods of enhancing axon regeneration. The common fibular (CF) and tibial (TIB) nerves of thy-1-YFP-H mice, in which axons in peripheral nerves are marked by yellow fluorescent protein (YFP), were transected and repaired using CF and TIB nerve grafts harvested from non-fluorescent donor mice. Silastic capsules filled with flutamide were implanted subcutaneously to release the drug continuously. Exercised mice were treadmill trained 5 days/week for 2 weeks, starting on the third day post-transection. For electrical stimulation, the sciatic nerve was stimulated continuously for 1 h prior to nerve transection. After 2 weeks, lengths of YFP+ profiles of regenerating axons were measured from harvested nerves. Both exercise and electrical stimulation enhanced axon regeneration, but this enhancement was blocked completely by flutamide treatments. Signaling through androgen receptors is necessary for the enhancing effects of treadmill exercise or electrical stimulation on axon regeneration in cut peripheral nerves. PMID:24293191

  17. Vitamin D and androgen receptor-targeted therapy for triple-negative breast cancer.

    PubMed

    Thakkar, A; Wang, B; Picon-Ruiz, M; Buchwald, P; Ince, Tan A

    2016-05-01

    Anti-estrogen and anti-HER2 treatments have been among the first and most successful examples of targeted therapy for breast cancer (BC). However, the treatment of triple-negative BC (TNBC) that lack estrogen receptor expression or HER2 amplification remains a major challenge. We previously discovered that approximately two-thirds of TNBCs express vitamin D receptor (VDR) and/or androgen receptor (AR) and hypothesized that TNBCs co-expressing AR and VDR (HR2-av TNBC) could be treated by targeting both of these hormone receptors. To evaluate the feasibility of VDR/AR-targeted therapy in TNBC, we characterized 15 different BC lines and identified 2 HR2-av TNBC lines and examined the changes in their phenotype, viability, and proliferation after VDR and AR-targeted treatment. Treatment of BC cell lines with VDR or AR agonists inhibited cell viability in a receptor-dependent manner, and their combination appeared to inhibit cell viability additively. Moreover, cell viability was further decreased when AR/VDR agonist hormones were combined with chemotherapeutic drugs. The mechanisms of inhibition by AR/VDR agonist hormones included cell cycle arrest and apoptosis in TNBC cell lines. In addition, AR/VDR agonist hormones induced differentiation and inhibited cancer stem cells (CSCs) measured by reduction in tumorsphere formation efficiency, high aldehyde dehydrogenase activity, and CSC markers. Surprisingly, we found that AR antagonists inhibited proliferation of most BC cell lines in an AR-independent manner, raising questions regarding their mechanism of action. In summary, AR/VDR-targeted agonist hormone therapy can inhibit HR2-av TNBC through multiple mechanisms in a receptor-dependent manner and can be combined with chemotherapy. PMID:27120467

  18. Timing of androgen receptor disruption and estrogen exposure underlies a spectrum of congenital penile anomalies

    PubMed Central

    Armfield, Brooke A.; Cohn, Martin J.

    2015-01-01

    Congenital penile anomalies (CPAs) are among the most common human birth defects. Reports of CPAs, which include hypospadias, chordee, micropenis, and ambiguous genitalia, have risen sharply in recent decades, but the causes of these malformations are rarely identified. Both genetic anomalies and environmental factors, such as antiandrogenic and estrogenic endocrine disrupting chemicals (EDCs), are suspected to cause CPAs; however, little is known about the temporal window(s) of sensitivity to EDCs, or the tissue-specific roles and downstream targets of the androgen receptor (AR) in external genitalia. Here, we show that the full spectrum of CPAs can be produced by disrupting AR at different developmental stages and in specific cell types in the mouse genital tubercle. Inactivation of AR during a narrow window of prenatal development results in hypospadias and chordee, whereas earlier disruptions cause ambiguous genitalia and later disruptions cause micropenis. The neonatal phase of penile development is controlled by the balance of AR to estrogen receptor α (ERα) activity; either inhibition of androgen or augmentation of estrogen signaling can induce micropenis. AR and ERα have opposite effects on cell division, apoptosis, and regulation of Hedgehog, fibroblast growth factor, bone morphogenetic protein, and Wnt signaling in the genital tubercle. We identify Indian hedgehog (Ihh) as a novel downstream target of AR in external genitalia and show that conditional deletion of Ihh inhibits penile masculinization. These studies reveal previously unidentified cellular and molecular mechanisms by which antiandrogenic and estrogenic signals induce penile malformations and demonstrate that the timing of endocrine disruption can determine the type of CPA. PMID:26598695

  19. Selective androgen receptor modulator RAD140 is neuroprotective in cultured neurons and kainate-lesioned male rats.

    PubMed

    Jayaraman, Anusha; Christensen, Amy; Moser, V Alexandra; Vest, Rebekah S; Miller, Chris P; Hattersley, Gary; Pike, Christian J

    2014-04-01

    The decline in testosterone levels in men during normal aging increases risks of dysfunction and disease in androgen-responsive tissues, including brain. The use of testosterone therapy has the potential to increase the risks for developing prostate cancer and or accelerating its progression. To overcome this limitation, novel compounds termed "selective androgen receptor modulators" (SARMs) have been developed that lack significant androgen action in prostate but exert agonist effects in select androgen-responsive tissues. The efficacy of SARMs in brain is largely unknown. In this study, we investigate the SARM RAD140 in cultured rat neurons and male rat brain for its ability to provide neuroprotection, an important neural action of endogenous androgens that is relevant to neural health and resilience to neurodegenerative diseases. In cultured hippocampal neurons, RAD140 was as effective as testosterone in reducing cell death induced by apoptotic insults. Mechanistically, RAD140 neuroprotection was dependent upon MAPK signaling, as evidenced by elevation of ERK phosphorylation and inhibition of protection by the MAPK kinase inhibitor U0126. Importantly, RAD140 was also neuroprotective in vivo using the rat kainate lesion model. In experiments with gonadectomized, adult male rats, RAD140 was shown to exhibit peripheral tissue-specific androgen action that largely spared prostate, neural efficacy as demonstrated by activation of androgenic gene regulation effects, and neuroprotection of hippocampal neurons against cell death caused by systemic administration of the excitotoxin kainate. These novel findings demonstrate initial preclinical efficacy of a SARM in neuroprotective actions relevant to Alzheimer's disease and related neurodegenerative diseases. PMID:24428527

  20. Selective Androgen Receptor Modulator RAD140 Is Neuroprotective in Cultured Neurons and Kainate-Lesioned Male Rats

    PubMed Central

    Jayaraman, Anusha; Christensen, Amy; Moser, V. Alexandra; Vest, Rebekah S.; Miller, Chris P.; Hattersley, Gary

    2014-01-01

    The decline in testosterone levels in men during normal aging increases risks of dysfunction and disease in androgen-responsive tissues, including brain. The use of testosterone therapy has the potential to increase the risks for developing prostate cancer and or accelerating its progression. To overcome this limitation, novel compounds termed “selective androgen receptor modulators” (SARMs) have been developed that lack significant androgen action in prostate but exert agonist effects in select androgen-responsive tissues. The efficacy of SARMs in brain is largely unknown. In this study, we investigate the SARM RAD140 in cultured rat neurons and male rat brain for its ability to provide neuroprotection, an important neural action of endogenous androgens that is relevant to neural health and resilience to neurodegenerative diseases. In cultured hippocampal neurons, RAD140 was as effective as testosterone in reducing cell death induced by apoptotic insults. Mechanistically, RAD140 neuroprotection was dependent upon MAPK signaling, as evidenced by elevation of ERK phosphorylation and inhibition of protection by the MAPK kinase inhibitor U0126. Importantly, RAD140 was also neuroprotective in vivo using the rat kainate lesion model. In experiments with gonadectomized, adult male rats, RAD140 was shown to exhibit peripheral tissue-specific androgen action that largely spared prostate, neural efficacy as demonstrated by activation of androgenic gene regulation effects, and neuroprotection of hippocampal neurons against cell death caused by systemic administration of the excitotoxin kainate. These novel findings demonstrate initial preclinical efficacy of a SARM in neuroprotective actions relevant to Alzheimer's disease and related neurodegenerative diseases. PMID:24428527

  1. Deletion of the steroid-binding domain of the human androgen receptor gene in one family with complete androgen insensitivity syndrome: Evidence for further genetic heterogeneity in this syndrome

    SciTech Connect

    Brown, T.R.; Lubahn, D.B.; Wilson, E.M.; Joseph, D.R.; French, F.S.; Migeon, C.J. )

    1988-11-01

    The cloning of a cDNA for the human androgen receptor gene has resulted in the availability for cDNA probes that span various parts of the gene, including the entire steroid-binding domain and part of the DNA-binding domain, as well as part of the 5' region of the gene. The radiolabeled probes were used to screen for androgen receptor mutations on Southern blots prepared by restriction endonuclease digestion of genomic DNA from human subjects with complete androgen insensitivity syndrome (AIS). In this investigation, the authors considered only patients presenting complete AIS and with the androgen receptor (-) form as the most probably subjects to show a gene deletion. One subject from each of six unrelated families with the receptor (-) form of complete AIS and 10 normal subjects were studied. In the 10 normal subjects and in 5 of the 6 patients, identical DNA restriction fragment patterns were observed with EcoRI and BamHI. Analysis of other members of this family confirmed the apparent gene deletion. The data provide direct proof that complete AIS in some families can result from a deletion of the androgen receptor structural gene. However, other families do not demonstrate such a deletion, suggesting that point mutations may also result in the receptor (-) form of complete AIS, adding further to the genetic heterogeneity of this syndrome.

  2. Sexual experience affects reproductive behavior and preoptic androgen receptors in male mice

    PubMed Central

    Swaney, William T.; Dubose, Brittany N.; Curley, James P.; Champagne, Frances A.

    2012-01-01

    Reproductive behavior in male rodents is made up of anticipatory and consummatory elements which are regulated in the brain by sensory systems, reward circuits and hormone signaling. Gonadal steroids play a key role in the regulation of male sexual behavior via steroid receptors in the hypothalamus and preoptic area. Typical patterns of male reproductive behavior have been characterized, however these are not fixed but are modulated by adult experience. We assessed the effects of repeated sexual experience on male reproductive behavior of C57BL/6 mice; including measures of olfactory investigation of females, mounting, intromission and ejaculation. The effects of sexual experience on the number of cells expressing either androgen receptor (AR) or estrogen receptor alpha (ERα) in the primary brain nuclei regulating male sexual behavior was also measured. Sexually experienced male mice engaged in less sniffing of females before initiating sexual behavior and exhibited shorter latencies to mount and intromit, increased frequency of intromission, and increased duration of intromission relative to mounting. No changes in numbers of ERα-positive cells were observed, however sexually experienced males had increased numbers of AR-positive cells in the medial preoptic area (MPOA); the primary regulatory nucleus for male sexual behavior. These results indicate that sexual experience results in a qualitative change in male reproductive behavior in mice that is associated with increased testosterone sensitivity in the MPOA and that this nucleus may play a key integrative role in mediating the effects of sexual experience on male behavior. PMID:22266118

  3. Effects of Androgen and Estrogen Receptor Signaling Pathways on Bladder Cancer Initiation and Progression

    PubMed Central

    Godoy, Guilherme; Gakis, Georgios; Smith, Carolyn L.; Fahmy, Omar

    2016-01-01

    Epidemiologic studies have long demonstrated clear differences in incidence and progression of bladder cancer between genders suggesting that the mechanisms of development and progression in these tumors have a strong association with steroid hormonal pathways. Such observations led to preclinical studies investigating the role of androgen and estrogen receptors, as well as their cognate hormones in bladder cancer initiation and progression. Using various in vitro cell line assays and in vivo mouse models, studies have elucidated different mechanisms and signaling pathways through which these steroid receptors may participate in this disease. More recently, RNA expression data from multiple studies revealed a luminal subtype of bladder cancer that exhibited an estrogen receptor signaling pathway, making it a strong candidate for further consideration of targeted therapies in the future. Despite the promising preclinical data demonstrating potential roles for both antiandrogen and antiestrogen strategies targeting these pathways in different stages of bladder cancer, only two clinical trials are currently active and accruing patients for such clinical studies. Targeted therapies in bladder cancer are a large unmet need and have the potential to change treatment paradigms and improve oncological outcomes of patients with bladder cancer. PMID:27376135

  4. Identification of SRC3/AIB1 as a Preferred Coactivator for Hormone-activated Androgen Receptor

    SciTech Connect

    Zhou, X. Edward; Suino-Powell, Kelly M.; Li, Jun; He, Yuanzheng; MacKeigan, Jeffrey P.; Melcher, Karsten; Yong, Eu-Leong; Xu, H.Eric

    2010-09-17

    Transcription activation by androgen receptor (AR), which depends on recruitment of coactivators, is required for the initiation and progression of prostate cancer, yet the mechanisms of how hormone-activated AR interacts with coactivators remain unclear. This is because AR, unlike any other nuclear receptor, prefers its own N-terminal FXXLF motif to the canonical LXXLL motifs of coactivators. Through biochemical and crystallographic studies, we identify that steroid receptor coactivator-3 (SRC3) (also named as amplified in breast cancer-1 or AIB1) interacts strongly with AR via synergistic binding of its first and third LXXLL motifs. Mutagenesis and functional studies confirm that SRC3 is a preferred coactivator for hormone-activated AR. Importantly, AR mutations found in prostate cancer patients correlate with their binding potency to SRC3, corroborating with the emerging role of SRC3 as a prostate cancer oncogene. These results provide a molecular mechanism for the selective utilization of SRC3 by hormone-activated AR, and they link the functional relationship between AR and SRC3 to the development and growth of prostate cancer.

  5. Hormone stimulation of androgen receptor mediates dynamic changes in DNA methylation patterns at regulatory elements

    PubMed Central

    Dhiman, Vineet K.; Attwood, Kristopher; Campbell, Moray J.; Smiraglia, Dominic J.

    2015-01-01

    DNA methylation is an epigenetic modification that contributes to stable gene silencing by interfering with the ability of transcriptional regulators to bind to DNA. Recent findings have revealed that hormone stimulation of certain nuclear receptors induces rapid, dynamic changes in DNA methylation patterns alongside transcriptional responses at a subset of target loci, over time. However, the ability of androgen receptor (AR) to dynamically regulate gene transcription is relatively under-studied and its role in the regulation of DNA methylation patterns remains to be elucidated. Here we demonstrate in normal prostate cells that hormone stimulated AR activity results in dynamic changes in the transcription rate and DNA methylation patterns at the AR target genes, TIPARP and SGK1. Time-resolved chromatin immunoprecipitation experiments on the SGK1 locus reveals dynamic recruitment of AR and RNA Polymerase II, as well as the recruitment of proteins involved in the DNA demethylation process, TET1 and TDG. Furthermore, the presence of DNA methylation at dynamic regions inhibits protein binding and transcriptional activity of SGK1. These findings establish AR activity as a contributing factor to the dynamic regulation of DNA methylation patterns at target genes in prostate biology and infer further complexity involved in nuclear receptor mediation of transcriptional regulation. PMID:26646795

  6. Regulation of uterine progesterone receptors by the nonsteroidal anti-androgen hydroxyflutamide

    SciTech Connect

    Chandrasekhar, Y.; Armstrong, D.T. )

    1991-07-01

    The authors have recently reported that the anti-androgen hydroxyflutamide causes delayed implantation and exhibits antideciduogenic activity in the rat. The present experiments were conducted to examine whether hydroxyflutamide binds to the uterine progesterone receptors and/or alters the progesterone binding sites in the uterus. Cytosol and nuclear fractions from decidualized rat uterus were incubated with (3H)-R5020 without or with increasing concentrations of radioinert R5020, RU486, dihydrotestosterone, or hydroxyflutamide. From the log-dose inhibition curves, the relative binding affinity of both hydroxyflutamide and dihydrotestosterone was less than 0.1% and 2%, compared with R5020 (100%) for displacing (3H)-R5020 bound to uterine cytosol and nuclear fractions, respectively. Injection of estradiol-17 beta (1 microgram/rat) to ovariectomized prepubertal rats induced a 1.85-fold increase in uterine weight by 24 h. Hydroxyflutamide at 2.5 or 5.0 mg did not significantly alter the estrogen-induced increase in uterine weight. Compared to vehicle alone, estrogen induced an approximately 5-fold increase in uterine cytosolic progesterone binding sites. Hydroxyflutamide at both 2.5- and 5.0-mg doses significantly attenuated the estrogen-induced elevation in uterine progesterone binding sites. These studies demonstrate that hydroxyflutamide does not bind with high affinity to progesterone receptors, but suppresses the estrogen-induced elevation in progesterone receptor levels in the uterus.

  7. Modulation of the cytosolic androgen receptor in striated muscle by sex steroids

    NASA Technical Reports Server (NTRS)

    Rance, N. E.; Max, S. R.

    1984-01-01

    The effects of orchiectomy (GDX) and of subsequent administration of testosterone propionate (TP) or 17(beta)-estradiol (E2) on the maximum binding (Bmax) and apparent Kd of the cytosolic androgen receptor in levator ani (LA) and skeletal muscles of adult male Sprague-Dawley rats are investigated experimentally. The results are presented in graphs and discussed. In LA, BMAX is found to rise from a control level of 2.5 fmol/mg protein to 280, 600, 478, and 133 percent of control at 12 h, 14 d, 30 d, and 44 d after GDX, respectively, while Kd increased only insignificantly (from 680 to 960 fM); Bmax is held at control levels for 6 h by cycloheximide given at GDX, is unaffected by TP given at 30 d, and is further increased (by 480 percent at 44 d) by administration of E2 at 30 d. Bmax in skeletal muscles is found to increase to 139, 212, 220, and 158 percent of control at 12 h, 14 d, 30 d, and 44 d, respectively; Bmax is returned to control at 44 d by TP at 30 d but is not affected by E2. The effect of E2 in LA is attributed to either induction of the cytosolic receptor or a decreased rate of receptor degradation.

  8. Extranuclear Actions of the Androgen Receptor Enhance Glucose-Stimulated Insulin Secretion in the Male.

    PubMed

    Navarro, Guadalupe; Xu, Weiwei; Jacobson, David A; Wicksteed, Barton; Allard, Camille; Zhang, Guanyi; De Gendt, Karel; Kim, Sung Hoon; Wu, Hongju; Zhang, Haitao; Verhoeven, Guido; Katzenellenbogen, John A; Mauvais-Jarvis, Franck

    2016-05-10

    Although men with testosterone deficiency are at increased risk for type 2 diabetes (T2D), previous studies have ignored the role of testosterone and the androgen receptor (AR) in pancreatic β cells. We show that male mice lacking AR in β cells (βARKO) exhibit decreased glucose-stimulated insulin secretion (GSIS), leading to glucose intolerance. The AR agonist dihydrotestosterone (DHT) enhances GSIS in cultured male islets, an effect that is abolished in βARKO(-/y) islets and human islets treated with an AR antagonist. In β cells, DHT-activated AR is predominantly extranuclear and enhances GSIS by increasing islet cAMP and activating the protein kinase A. In mouse and human islets, the insulinotropic effect of DHT depends on activation of the glucagon-like peptide-1 (GLP-1) receptor, and accordingly, DHT amplifies the incretin effect of GLP-1. This study identifies AR as a novel receptor that enhances β cell function, a finding with implications for the prevention of T2D in aging men. PMID:27133133

  9. Endostatin: A novel inhibitor of androgen receptor function in prostate cancer

    PubMed Central

    Lee, Joo Hyoung; Isayeva, Tatyana; Larson, Matthew R.; Sawant, Anandi; Cha, Ha-Ram; Chanda, Diptiman; Chesnokov, Igor N.; Ponnazhagan, Selvarangan

    2015-01-01

    Acquired resistance to androgen receptor (AR)-targeted therapies compels the development of novel treatment strategies for castration-resistant prostate cancer (CRPC). Here, we report a profound effect of endostatin on prostate cancer cells by efficient intracellular trafficking, direct interaction with AR, reduction of nuclear AR level, and down-regulation of AR-target gene transcription. Structural modeling followed by functional analyses further revealed that phenylalanine-rich α1-helix in endostatin—which shares structural similarity with noncanonical nuclear receptor box in AR—antagonizes AR transcriptional activity by occupying the activation function (AF)-2 binding interface for coactivators and N-terminal AR AF-1. Together, our data suggest that endostatin can be recognized as an endogenous AR inhibitor that impairs receptor function through protein–protein interaction. These findings provide new insights into endostatin whose antitumor effect is not limited to inhibiting angiogenesis, but can be translated to suppressing AR-mediated disease progression in CRPC. PMID:25605930

  10. Ablation of the androgen receptor from vascular smooth muscle cells demonstrates a role for testosterone in vascular calcification

    PubMed Central

    Zhu, Dongxing; Hadoke, Patrick W. F.; Wu, Junxi; Vesey, Alex T.; Lerman, Daniel. A.; Dweck, Marc R.; Newby, David E.; Smith, Lee B.; MacRae, Vicky E.

    2016-01-01

    Vascular calcification powerfully predicts mortality and morbidity from cardiovascular disease. Men have a greater risk of cardiovascular disease, compared to women of a similar age. These gender disparities suggest an influence of sex hormones. Testosterone is the primary and most well-recognised androgen in men. Therefore, we addressed the hypothesis that exogenous androgen treatment induces vascular calcification. Immunohistochemical analysis revealed expression of androgen receptor (AR) in the calcified media of human femoral artery tissue and calcified human valves. Furthermore, in vitro studies revealed increased phosphate (Pi)-induced mouse vascular smooth muscle cell (VSMC) calcification following either testosterone or dihydrotestosterone (DHT) treatment for 9 days. Testosterone and DHT treatment increased tissue non-specific alkaline phosphatase (Alpl) mRNA expression. Testosterone-induced calcification was blunted in VSMC-specific AR-ablated (SM-ARKO) VSMCs compared to WT. Consistent with these data, SM-ARKO VSMCs showed a reduction in Osterix mRNA expression. However, intriguingly, a counter-intuitive increase in Alpl was observed. These novel data demonstrate that androgens play a role in inducing vascular calcification through the AR. Androgen signalling may represent a novel potential therapeutic target for clinical intervention. PMID:27095121

  11. Androgen receptor modulates Foxp3 expression in CD4+CD25+Foxp3+ regulatory T-cells

    PubMed Central

    Walecki, Magdalena; Eisel, Florian; Klug, Jörg; Baal, Nelli; Paradowska-Dogan, Agnieszka; Wahle, Eva; Hackstein, Holger; Meinhardt, Andreas; Fijak, Monika

    2015-01-01

    CD4+CD25+Foxp3+ regulatory T (Treg) cells are able to inhibit proliferation and cytokine production in effector T-cells and play a major role in immune responses and prevention of autoimmune disease. A master regulator of Treg cell development and function is the transcription factor Foxp3. Several cytokines, such as TGF-β and IL-2, are known to regulate Foxp3 expression as well as methylation of the Foxp3 locus. We demonstrated previously that testosterone treatment induces a strong increase in the Treg cell population both in vivo and in vitro. Therefore we sought to investigate the direct effect of androgens on expression and regulation of Foxp3. We show a significant androgen-dependent increase of Foxp3 expression in human T-cells from women in the ovulatory phase of the menstrual cycle but not from men and identify a functional androgen response element within the Foxp3 locus. Binding of androgen receptor leads to changes in the acetylation status of histone H4, whereas methylation of defined CpG regions in the Foxp3 gene is unaffected. Our results provide novel evidence for a modulatory role of androgens in the differentiation of Treg cells. PMID:26063731

  12. Rapid increase of spines by dihydrotestosterone and testosterone in hippocampal neurons: Dependence on synaptic androgen receptor and kinase networks.

    PubMed

    Hatanaka, Yusuke; Hojo, Yasushi; Mukai, Hideo; Murakami, Gen; Komatsuzaki, Yoshimasa; Kim, Jonghyuk; Ikeda, Muneki; Hiragushi, Ayako; Kimoto, Tetsuya; Kawato, Suguru

    2015-09-24

    Rapid modulation of hippocampal synaptic plasticity by locally synthesized androgen is important in addition to circulating androgen. Here, we investigated the rapid changes of dendritic spines in response to the elevation of dihydrotestosterone (DHT) and testosterone (T), by using hippocampal slices from adult male rats, in order to clarify whether these signaling processes include synaptic/extranuclear androgen receptor (AR) and activation of kinases. We found that the application of 10nM DHT and 10nM T increased the total density of spines by approximately 1.3-fold within 2h, by imaging Lucifer Yellow-injected CA1 pyramidal neurons. Interestingly, DHT and T increased different head-sized spines. While DHT increased middle- and large-head spines, T increased small-head spines. Androgen-induced spinogenesis was suppressed by individually blocking Erk MAPK, PKA, PKC, p38 MAPK, LIMK or calcineurin. On the other hand, blocking CaMKII did not inhibit spinogenesis. Blocking PI3K altered the spine head diameter distribution, but did not change the total spine density. Blocking mRNA and protein synthesis did not suppress the enhancing effects induced by DHT or T. The enhanced spinogenesis by androgens was blocked by AR antagonist, which AR was localized postsynaptically. Taken together, these results imply that enhanced spinogenesis by DHT and T is mediated by synaptic/extranuclear AR which rapidly drives the kinase networks. This article is part of a Special Issue entitled SI: Brain and Memory. PMID:25511993

  13. Ablation of the androgen receptor from vascular smooth muscle cells demonstrates a role for testosterone in vascular calcification.

    PubMed

    Zhu, Dongxing; Hadoke, Patrick W F; Wu, Junxi; Vesey, Alex T; Lerman, Daniel A; Dweck, Marc R; Newby, David E; Smith, Lee B; MacRae, Vicky E

    2016-01-01

    Vascular calcification powerfully predicts mortality and morbidity from cardiovascular disease. Men have a greater risk of cardiovascular disease, compared to women of a similar age. These gender disparities suggest an influence of sex hormones. Testosterone is the primary and most well-recognised androgen in men. Therefore, we addressed the hypothesis that exogenous androgen treatment induces vascular calcification. Immunohistochemical analysis revealed expression of androgen receptor (AR) in the calcified media of human femoral artery tissue and calcified human valves. Furthermore, in vitro studies revealed increased phosphate (Pi)-induced mouse vascular smooth muscle cell (VSMC) calcification following either testosterone or dihydrotestosterone (DHT) treatment for 9 days. Testosterone and DHT treatment increased tissue non-specific alkaline phosphatase (Alpl) mRNA expression. Testosterone-induced calcification was blunted in VSMC-specific AR-ablated (SM-ARKO) VSMCs compared to WT. Consistent with these data, SM-ARKO VSMCs showed a reduction in Osterix mRNA expression. However, intriguingly, a counter-intuitive increase in Alpl was observed. These novel data demonstrate that androgens play a role in inducing vascular calcification through the AR. Androgen signalling may represent a novel potential therapeutic target for clinical intervention. PMID:27095121

  14. The xenoestrogen bisphenol A in the Hershberger assay: androgen receptor regulation and morphometrical reactions indicate no major effects.

    PubMed

    Nishino, Tsuyuki; Wedel, Thilo; Schmitt, Oliver; Schönfelder, Martin; Hirtreiter, Christian; Schulz, Thorsten; Kühnel, Wolfgang; Michna, Horst

    2006-02-01

    We evaluated androgen-like effects of bisphenol A (BPA) using orchiectomized Wistar rats. Animals were treated p.o. either with vehicle or with 3, 50, 200, 500 mg/kgbw/day BPA (n=13) for 7 days. One group was treated s.c. with 1mg/kgbw/day testosterone propionate (TP). Flutamide (FL) (3mg/kgbw/day, p.o.) was used to antagonize androgen effects of the suprapharmacological dose (500 mg/kgbw/day) of BPA. Androgen-like effects of BPA on prostates and seminal vesicles were assessed by the Hershberger assay, densitometric analysis of androgen receptor (AR) immunoreactivity, cell proliferation-index and a morphometric analysis. Absolute weights of prostates and seminal vesicles were not increased by BPA, whereas the relative weights were increased at higher doses of BPA, most likely due to a decrease in body weight. Staining intensity for AR immunoreactivity was increased at low but not at higher doses of BPA in comparison to the orchiectomized rats. BPA at all doses tested did not cause an increase of the cell proliferation-index. Epithelial height and glandular luminal area were increased by low doses of BPA, whereas higher doses caused a decrease of these parameters. The data provide evidence that BPA does not exert major androgenic effects. PMID:16406770

  15. Interleukin-6 regulates androgen receptor activity and prostate cancer cell growth.

    PubMed

    Culig, Zoran; Bartsch, Georg; Hobisch, Alfred

    2002-11-29

    Interleukin-6 (IL-6) is a multifunctional cytokine which is involved in regulation of growth of various malignant tumors. IL-6 binds to its receptor, which is composed of a ligand-binding and a signal-transducing subunit and activates pathways of signal transducers and activators of transcription and mitogen-activated protein kinases (MAPKs). In prostate cancer cells, IL-6 induces divergent proliferative responses. Serum levels of IL-6 are elevated in patients with therapy-resistant carcinoma of the prostate. We have investigated whether IL-6 interacts with the androgen signaling pathway in prostate cancer cells. In DU-145 cells, transiently transfected with androgen receptor (AR) cDNA, IL-6 caused ligand-independent and synergistic activation of the AR. Nonsteroidal antagonists of the AR down-regulated AR activity induced by IL-6. In LNCaP cells, IL-6-induced expression of the AR-regulated prostate-specific antigen gene. Inhibitors of protein kinase A and C and MAPK down-regulated IL-6-induced AR activity. IL-6 expression in human prostate tissue was studied by immunohistochemistry. In benign prostatic tissue, IL-6 immunoreactivity was confined to basal cells. In prostate intraepithelial neoplasia and in cancer tissue, atypical intraluminal and cancer cells expressed IL-6. The expression of IL-6 receptor was demonstrated in benign and malignant tissue in both epithelium and stroma. In the authors' laboratory, IL-6-inhibited proliferation of parental LNCaP cells. A new LNCaP subline was generated to investigate changes in signal transduction which might occur after prolonged treatment with IL-6. In the subline LNCaP-IL-6+, IL-6 neither reduced a number of cells nor caused G1 growth arrest. IL-6 receptor expression declined during long-term IL-6 treatment. However, IL-6-up-regulated AR expression and was capable of inducing AR activity in LNCaP-IL-6+ cells. Parental LNCaP cells do not express IL-6. In contrast, IL-6 mRNA and protein expression were detectable in

  16. CUDC-101, a Novel Inhibitor of Full-Length Androgen Receptor (flAR) and Androgen Receptor Variant 7 (AR-V7) Activity: Mechanism of Action and In Vivo Efficacy.

    PubMed

    Sun, Huiying; Mediwala, Sanjay N; Szafran, Adam T; Mancini, Michael A; Marcelli, Marco

    2016-06-01

    Castration-resistant prostate cancer (CRPC) is an androgen receptor (AR)-dependent disease expected to cause the death of more than 27,000 Americans in 2015. There are only a few available treatments for CRPC, making the discovery of new drugs an urgent need. We report that CUDC-101 (an inhibitor od HER2/NEU, EGFR and HDAC) inhibits both the full length AR (flAR) and the AR variant AR-V7. This observation prompted experiments to discover which of the known activities of CUDC-101 is responsible for the inhibition of flAR/AR-V7 signaling. We used pharmacologic and genetic approaches, and found that the effect of CUDC-101 on flAR and AR-V7 was duplicated only by other HDAC inhibitors, or by silencing the HDAC isoforms HDAC5 and HDAC10. We observed that CUDC-101 treatment or AR-V7 silencing by RNAi equally reduced transcription of the AR-V7 target gene, PSA, without affecting viability of 22Rv1 cells. However, when cellular proliferation was used as an end point, CUDC-101 was more effective than AR-V7 silencing, raising the prospect that CUDC-101 has additional targets beside AR-V7. In support of this, we found that CUDC-101 increased the expression of the cyclin-dependent kinase inhibitor p21, and decreased that of the oncogene HER2/NEU. To determine if CUDC-101 reduces growth in a xenograft model of prostate cancer, this drug was given for 14 days to castrated male SCID mice inoculated with 22Rv1 cells. Compared to vehicle, CUDC-101 reduced xenograft growth in a statistically significant way, and without macroscopic side effects. These studies demonstrate that CUDC-101 inhibits wtAR and AR-V7 activity and growth of 22Rv1 cells in vitro and in vivo. These effects result from the ability of CUDC-101 to target not only HDAC signaling, which was associated with decreased flAR and AR-V7 activity, but multiple additional oncogenic pathways. These observations raise the possibility that treatment of CRPC may be achieved by using similarly multi-targeted approaches. PMID

  17. CCAR1 promotes chromatin loading of androgen receptor (AR) transcription complex by stabilizing the association between AR and GATA2

    PubMed Central

    Seo, Woo-Young; Jeong, Byong Chang; Yu, Eun Ji; Kim, Hwa Jin; Kim, Seok-Hyung; Lim, Joung Eun; Kwon, Ghee Young; Lee, Hyun Moo; Kim, Jeong Hoon

    2013-01-01

    Androgen receptor (AR), a ligand-dependent transcription factor, plays a critical role in prostate cancer onset and progression, and its transcriptional function is mediated largely by distinct nuclear receptor co-regulators. Here, we show that cell cycle and apoptosis regulator 1 (CCAR1) functions as an AR co-activator. CCAR1 interacted with and enhanced the transcriptional activity of AR. Depletion of CCAR1 caused reduction in androgen-dependent expression of a subset of AR target genes. We further showed that CCAR1 is required for recruitment of AR, MED1 and RNA polymerase II to the enhancers of AR target genes and for androgen-induced long-range prostate specific antigen enhancer–promoter interaction. The molecular mechanism underlying CCAR1 function in AR-mediated transcription involves CCAR1-mediated enhanced recruitment of GATA2, a pioneer factor for AR, to AR-binding sites. CCAR1 stabilized the interaction between AR and GATA2 by interacting directly with both proteins, thereby facilitating AR and GATA2 occupancy on the enhancers. Furthermore, CCAR1 depletion inhibited the growth, migration, invasion of prostate cancer cells and reduced the tumorigenicity of prostate cancer cells in vivo. Our results firmly established CCAR1 as an AR co-activator that plays a key role in AR transcription complex assembly and has an important physiological role in androgen signaling and prostate tumorigenesis. PMID:23887938

  18. SPECIES DIFFERENCES IN ANDROGEN AND ESTROGEN RECEPTOR STRUCTURE AND FUNCTION AMONG VERTEBRATES AND INVERTEBRATES FOR INTERSPECIES EXTRAPOLATION OF ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    In vitro screening assays designed to identify hormone minics or antagonists, including the EDSTAC Tier 1 Screening (TIS) Battery, typically use only mammalian estrogen (ER) and androgen receptors (AR). However, there is uncertainty concerning species differences in binding affin...

  19. Molecular Cloning and Characterization of Estrogen, Androgen, and Progesterone Nuclear Receptors from a Freshwater Turtle (Pseudemys nelsoni)

    PubMed Central

    Katsu, Yoshinao; Ichikawa, Rie; Ikeuchi, Toshitaka; Kohno, Satomi; Guillette, Louis J.; Iguchi, Taisen

    2008-01-01

    Steroid hormones are essential for the normal function of many organ systems in vertebrates. Reproductive activity in females and males, such as the differentiation, growth, and maintenance of the reproductive system, requires signaling by the sex steroids. Although extensively studied in mammals and a few fish, amphibians, and bird species, the molecular mechanisms of sex steroid hormone (estrogens, androgens, and progestins) action are poorly understood in reptiles. Here we evaluate hormone receptor ligand interactions in a freshwater turtle, the red-belly slider (Pseudemys nelsoni), after the isolation of cDNAs encoding an estrogen receptor alpha (ERα), an androgen receptor (AR), and a progesterone receptor (PR). The full-length red-belly slider turtle (t)ERα, tAR, and tPR cDNAs were obtained using 5′ and 3′ rapid amplification cDNA ends. The deduced amino acid sequences showed high identity to the chicken orthologs (tERα, 90%; tAR, 71%; tPR, 71%). Using transient transfection assays of mammalian cells, tERα protein displayed estrogen-dependent activation of transcription from an estrogen-responsive element-containing promoter. The other receptor proteins, tAR and tPR, also displayed androgen- or progestin-dependent activation of transcription from androgen- and progestin-responsive murine mammary tumor virus promoters. We further examined the transactivation of tERα, tAR and tPR by ligands using a modified GAL4-transactivation system. We found that the GAL4-transactivation system was not suitable for the measurement of tAR and tPR transactivations. This is the first report of the full coding regions of a reptilian AR and PR and the examination of their transactivation by steroid hormones. PMID:17916628

  20. Androgen regulation of corticotropin-releasing hormone receptor 2 (CRHR2) mRNA expression and receptor binding in the rat brain

    PubMed Central

    Weiser, Michael J.; Goel, Nirupa; Sandau, Ursula S.; Bale, Tracy L.; Handa, Robert J.

    2008-01-01

    Stress-induced affective disorders, such as depression and anxiety, are more prevalent in females than in males. The reduced vulnerability to these disorders in males may be due to the presence of androgens, which are known to dampen the stress response and reduce anxiety-like behaviors. However, a neurobiological mechanism for this sex difference has yet to be elucidated. Corticotropin-releasing hormone receptor 2 (CRHR2) has been implicated in regulating anxiety-type behaviors and is expressed in stress-responsive brain regions that also contain androgen receptors (AR). We hypothesized that androgen may exert its effects through actions on CRHR2 and we therefore examined the regulation of CRHR2 mRNA and receptor binding in the male rat forebrain following androgen administration. Young adult male Sprague/Dawley rats were gonadectomized (GDX) and treated with the non-aromatizable androgen, dihydrotestosterone propionate (DHTP) using hormone filled Silastic capsules. Control animals received empty capsules. Using quantitative real time RT-PCR, CRHR2 mRNA levels were determined in block dissected brain regions. DHTP treatment significantly increased CRHR2 mRNA expression in the hippocampus, hypothalamus, and lateral septum (p < 0.01) when compared to vehicle-treated controls. A similar trend was observed in amygdala (p = 0.05). Furthermore, in vitro autoradiography revealed significantly higher CRHR2 binding in the lateral septum in androgen-treated males, with the highest difference observed in the ventral lateral region. Regulation of CRHR2 mRNA by AR was also examined using an in vitro approach. Hippocampal neurons, which contain high levels of AR, were harvested from E17–18 rat fetuses, and maintained in primary culture for 14 days. Neurons were then treated with dihydrotestosterone (DHT; 1 nM), DHT plus flutamide (an androgen receptor antagonist), or vehicle for 48 hours. CRHR2 mRNA levels were measured using quantitative real time RT-PCR. Consistent with in

  1. A Molecular Analysis Provides Novel Insights into Androgen Receptor Signalling in Breast Cancer

    PubMed Central

    Mehta, Jatin; Asthana, Shailendra; Mandal, Chandi Charan; Saxena, Sunita

    2015-01-01

    Background Androgen Receptor (AR) is an essential transcription factor for the development of secondary sex characteristics, spermatogenesis and carcinogenesis. Recently AR has been implicated in the development and progression of breast and prostate cancers. Although some of the functions of the AR are known but the mechanistic details of these divergent processes are still not clear. Therefore understanding the regulatory mechanisms of the functioning of the AR in ER-/AR+ breast cancer will provide many novel targets for the purpose of therapeutic intervention. Methods/Results Using bioinformatics tools, we have identified 75 AR targets having prominent roles in cell cycle, apoptosis and metabolism. Herein, we validated 10 genes as AR targets by studying the regulation of these genes in MDA-MB-453 cell line on stimulation by androgens like 5α-dihydrotestosterone (DHT), using RT-qPCR and ChIP assay. It was observed that all the identified genes involved in cell cycle except MAD1L1 were found to be up regulated whereas expression of apoptosis related genes was decreased in response to DHT treatment. We performed an exhaustive, rigid-body docking between individual ARE and DNA binding domain (DBD) of the AR protein and it was found that novel residues K567, K588, K591 and R592 are involved in the process of DNA binding. To verify these specific DNA-protein interactions electrostatic energy term calculations for each residue was determined using the linearized Poisson–Boltzmann equation. Our experimental data showed that treatment of breast cancer cells with DHT promotes cell proliferation and decreases apoptosis. It was observed that bicalutamide treatment was able to reverse the effect of DHT. Conclusion Taken together, our results provide new insights into the mechanism by which AR promotes breast cancer progression. Moreover our work proposes to use bicalutamide along with taxanes as novel therapy for the treatment of TNBCs, which are positive for downstream

  2. Overview on the complexity of androgen receptor-targeted therapy for prostate cancer.

    PubMed

    Farooqi, Ammad Ahmad; Sarkar, Fazlul H

    2015-01-01

    In the past decades, the field of prostate cancer (PCa) biology has developed exponentially and paralleled with that has been the growing interest in translation of laboratory findings into clinical practice. Based on overwhelming evidence of high impact research findings which support the underlying cause of insufficient drug efficacy in patients progressing on standard androgen deprivation therapy (ADT) is due to persistent activation of the androgen receptor (AR) signaling axis. Therefore, newer agents must be discovered especially because newer ADT such as abiraterone and enzalutamide are becoming ineffective due to rapid development of resistance to these agents. High-throughput technologies are generating massive and highly dimensional genetic variation data that has helped in developing a better understanding of the dynamic repertoire of AR and AR variants. Full length AR protein and its variants modulate a sophisticated regulatory system to orchestrate cellular responses. We partition this multicomponent review into subsections addressing the underlying mechanisms of resistance to recent therapeutics, positive and negative regulators of AR signaling cascade, and how SUMOylation modulates AR induced transcriptional activity. Experimentally verified findings obtained from cell culture and preclinical studies focusing on the potential of natural agents in inhibiting mRNA/protein levels of AR, nuclear accumulation and enhanced nuclear export of AR are also discussed. We also provide spotlight on molecular basis of enzalutamide resistance with an overview of the strategies opted to overcome such resistance. AR variants are comprehensively described and different mechanisms that regulate AR variant expression are also discussed. Reconceptualization of phenotype- and genotype-driven studies have convincingly revealed that drug induced resistance is a major stumbling block in standardization of therapy. Therefore, we summarize succinctly the knowledge of drug

  3. CAG Repeat Number in the Androgen Receptor Gene and Prostate Cancer

    PubMed Central

    Madjunkova, S; Eftimov, A; Georgiev, V; Petrovski, D; Dimovski, AJ; Plaseska-Karanfilska, D

    2012-01-01

    Prostate cancer (PC) is the second leading cause of cancer deaths in men. The effects of androgens on prostatic tissue are mediated by the androgen receptor (AR) gene. The 5′ end of exon 1 of the AR gene includes a polymorphic CAG triplet repeat that numbers between 10 to 36 in the normal population. The length of the CAG repeats is inversely related to the transactivation function of the AR gene. There is controversy over association between short CAG repeat numbers in the AR gene and PC. This retrospective case-control study evaluates the possible effect of short CAG repeats on the AR gene in prostate cancer risk in Macedonian males. A total of 392 male subjects, 134 PC patients, 106 patients with benign prostatic hyperplasia (BPH) and 152 males from the general Macedonian population were enrolled in this study. The CAG repeat length was determined by fluorescent polymerase chain reaction (PCR) amplification of exon1 of the AR gene followed by capillary electrophoresis (CE) on a genetic analyzer. The mean repeat length in PC patients was 21.5 ± 2.65, in controls 22.28 ± 2.86 (p = 0.009) and in BPH patients 22.1 ± 2.52 (p = 0.038). Short CAG repeats (<19) were found in 21.64% of PC patients vs. 9.43% in BPH patients (p = 0.0154). We also found an association of low Gleason score (<7) with short CAG repeat (<19) in PC patients (p = 0.0306), and no association between the age at diagnosis of PC and BPH and CAG repeat length. These results suggest that reduced CAG repeat length may be associated with increased prostate cancer risk in Macedonian men. PMID:24052720

  4. Temporal role of Sertoli cell androgen receptor expression in spermatogenic development.

    PubMed

    Hazra, Rasmani; Corcoran, Lisa; Robson, Mat; McTavish, Kirsten J; Upton, Dannielle; Handelsman, David J; Allan, Charles M

    2013-01-01

    Sertoli cell (SC) androgen receptor (AR) activity is vital for spermatogenesis. We created a unique gain-of-function transgenic (Tg) mouse model to determine the temporal role of SCAR expression in testicular development. The SC-specific rat Abpa promoter directed human Tg AR [Tg SC-specific AR (TgSCAR)] expression, providing strong premature postnatal AR immunolocalized to SC nuclei. Independent Tg lines revealed that TgSCAR dose dependently reduced postnatal and mature testis size (to 60% normal), whereas androgen-dependent mature seminal vesicle weights and serum testosterone levels remained normal. Total SC numbers were reduced in developing and mature TgSCAR testes, despite normal or higher Fshr mRNA and circulating FSH levels. Postnatal TgSCAR testes exhibited elevated levels of AR-regulated Rhox5 and Spinlw1 transcripts, and precocious SC function was demonstrated by early seminiferous tubular lumen formation and up-regulated expression of crucial SC tight-junction (Cldn11 and Tjp1) and phagocytic (Elmo1) transcripts. Early postnatal Amh expression was elevated but declined to normal levels in peripubertal-pubertal TgSCAR vs. control testes, indicating differential age-related regulation featuring AR-independent Amh down-regulation. TgSCAR induced premature postnatal spermatogenic development, shown by increased levels of meiotic (Dmc1 and Spo11) and postmeiotic (Capza3 and Prm1) germ cell transcripts, elevated meiotic-postmeiotic germ:Sertoli cell ratios, and accelerated spermatid development. Meiotic germ:Sertoli cell ratios were further increased in adult TgSCAR mice, indicating predominant SCAR-mediated control of meiotic development. However, postmeiotic germ:Sertoli cell ratios declined below normal. Our unique TgSCAR paradigm reveals that atypical SC-specific temporal AR expression provides a direct molecular mechanism for induction of precocious testicular development, leading to reduced adult testis size and decreased postmeiotic development. PMID

  5. Sox2 Is an Androgen Receptor-Repressed Gene That Promotes Castration-Resistant Prostate Cancer

    PubMed Central

    Kregel, Steven; Kiriluk, Kyle J.; Rosen, Alex M.; Cai, Yi; Reyes, Edwin E.; Otto, Kristen B.; Tom, Westin; Paner, Gladell P.; Szmulewitz, Russell Z.; Vander Griend, Donald J.

    2013-01-01

    Despite advances in detection and therapy, castration-resistant prostate cancer continues to be a major clinical problem. The aberrant activity of stem cell pathways, and their regulation by the Androgen Receptor (AR), has the potential to provide insight into novel mechanisms and pathways to prevent and treat advanced, castrate-resistant prostate cancers. To this end, we investigated the role of the embryonic stem cell regulator Sox2 [SRY (sex determining region Y)-box 2] in normal and malignant prostate epithelial cells. In the normal prostate, Sox2 is expressed in a portion of basal epithelial cells. Prostate tumors were either Sox2-positive or Sox2-negative, with the percentage of Sox2-positive tumors increasing with Gleason Score and metastases. In the castration-resistant prostate cancer cell line CWR-R1, endogenous expression of Sox2 was repressed by AR signaling, and AR chromatin-IP shows that AR binds the enhancer element within the Sox2 promoter. Likewise, in normal prostate epithelial cells and human embryonic stem cells, increased AR signaling also decreases Sox2 expression. Resistance to the anti-androgen MDV3100 results in a marked increase in Sox2 expression within three prostate cancer cell lines, and in the castration-sensitive LAPC-4 prostate cancer cell line ectopic expression of Sox2 was sufficient to promote castration-resistant tumor formation. Loss of Sox2 expression in the castration-resistant CWR-R1 prostate cancer cell line inhibited cell growth. Up-regulation of Sox2 was not associated with increased CD133 expression but was associated with increased FGF5 (Fibroblast Growth Factor 5) expression. These data propose a model of elevated Sox2 expression due to loss of AR-mediated repression during castration, and consequent castration-resistance via mechanisms not involving induction of canonical embryonic stem cell pathways. PMID:23326489

  6. Influence of Androgen Receptor in Vascular Cells on Reperfusion following Hindlimb Ischaemia

    PubMed Central

    Hadoke, Patrick W. F.; Takov, Kaloyan; Korczak, Agnieszka; Denvir, Martin A.; Smith, Lee B.

    2016-01-01

    Aims Studies in global androgen receptor knockout (G-ARKO) and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall. Methods and Results Mice with selective deletion of AR (ARKO) from vascular smooth muscle cells (SM-ARKO), endothelial cells (VE-ARKO), or both (SM/VE-ARKO) were compared with wild type (WT) controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO) did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture) model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10−10–10-7M; 6 days). Conclusion These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis. PMID:27159530

  7. LncRNA-Dependent Mechanisms of Androgen Receptor-regulated Gene Activation Programs

    PubMed Central

    Jin, Chunyu; Yang, Joy C.; Tanasa, Bogdan; Li, Wenbo; Merkurjev, Daria; Ohgi, Kenneth A.; Meng, Da; Zhang, Jie; Evans, Christopher P.; Rosenfeld, Michael G.

    2014-01-01

    While recent studies indicated roles of long non-coding RNAs (lncRNAs) in physiologic aspects of cell-type determination and tissue homeostasis1 yet their potential involvement in regulated gene transcription programs remain rather poorly understood. Androgen receptor (AR) regulates a large repertoire of genes central to the identity and behavior of prostate cancer cells2, and functions in a ligand-independent fashion in many prostate cancers when they become hormone refractory after initial androgen deprivation therapy3. Here, we report that two lncRNAs highly overexpressed in aggressive prostate cancer, PRNCR1 and PCGEM1, bind successively to the AR and strongly enhance both ligand-dependent and ligand-independent AR-mediated gene activation programs and proliferation in prostate cancer cells. Binding of PRNCR1 to the C-terminally acetylated AR on enhancers and its association with DOT1L appear to be required for recruitment of the second lncRNA, PCGEM1, to the DOT1L-mediated methylated AR N-terminus. Unexpectedly, recognition of specific protein marks by PCGEM1-recruited Pygopus2 PHD domain proves to enhance selective looping of AR-bound enhancers to target gene promoters in these cells. In “resistant” prostate cancer cells, these overexpressed lncRNAs can interact with, and are required for, the robust activation of both truncated and full length AR, causing ligand-independent activation of the AR transcriptional program and cell proliferation. Conditionally-expressed short hairpin RNA (shRNA) targeting of these lncRNAs in castration-resistant prostate cancer (CRPC) cell lines strongly suppressed tumor xenograft growth in vivo. Together, these results suggest that these overexpressed lncRNAs can potentially serve as a required component of castration-resistance in prostatic tumors. PMID:23945587

  8. Neural Androgen Receptors Modulate Gene Expression and Social Recognition But Not Social Investigation

    PubMed Central

    Karlsson, Sara A.; Studer, Erik; Kettunen, Petronella; Westberg, Lars

    2016-01-01

    The role of sex and androgen receptors (ARs) for social preference and social memory is rather unknown. In this study of mice we compared males, females and males lacking ARs specifically in the nervous system, ARNesDel, with respect to social preference, assessed with the three-chambered apparatus test, and social recognition, assessed with the social discrimination procedure. In the social discrimination test we also evaluated the tentative importance of the sex of the stimulus animal. Novel object recognition and olfaction were investigated to complement the results from the social tests. Gene expression analysis was performed to reveal molecules involved in the effects of sex and androgens on social behaviors. All three test groups showed social preference in the three-chambered apparatus test. In both social tests an AR-independent sexual dimorphism was seen in the persistence of social investigation of female conspecifics, whereas the social interest toward male stimuli mice was similar in all groups. Male and female controls recognized conspecifics independent of their sex, whereas ARNesDel males recognized female but not male stimuli mice. Moreover, the non-social behaviors were not affected by AR deficiency. The gene expression analyses of hypothalamus and amygdala indicated that Oxtr, Cd38, Esr1, Cyp19a1, Ucn3, Crh, and Gtf2i were differentially expressed between the three groups. In conclusion, our results suggest that ARs are required for recognition of male but not female conspecifics, while being dispensable for social investigation toward both sexes. In addition, the AR seems to regulate genes related to oxytocin, estrogen and William’s syndrome. PMID:27014003

  9. Antimullerian Hormone and Its Receptor Gene Expression in Prenatally Androgenized Female Rats

    PubMed Central

    Daneshian, Zahra; Ramezani Tehrani, Fahimeh; Zarkesh, Maryam; Norooz Zadeh, Mahsa; Mahdian, Reza; Zadeh Vakili, Azita

    2015-01-01

    Background: Anti-mullerian hormone (AMH) levels reflect the number of small antral follicles in ovaries and expression changes of AMH and its receptor are suspected to be involved in the pathogenesis of polycystic ovary syndrome (PCOS). Objectives: The aim of this study was to evaluate gene expression of AMH and its receptor in immature and adult rats prenatally exposed to androgen excess. Materials and Methods: Six pregnant Wistar rats in the experimental group were treated by subcutaneous injection of 5 mg free testosterone on day 20 of pregnancy, while controls (n = 6) received only 500 mL of solvent. Female pups of each mother were randomly divided into three groups as day 0 (newborn), 10-day old and days 75-85 (adult). RNAs were extracted from ovarian tissues and relative expression levels for AMH and its receptor genes were measured using TaqMan Real-Time PCR. Serum AMH and testosterone levels were measured using ELISA method. Results: Relative AMH expression decreased in newborns, 10-day olds and adults (0.806, 0.443 and 0.809 fold, respectively). AMHR expression was higher in newborns and adults (1.432 and 1.057 fold, respectively), while it decreased by 0.263 fold in 10-day olds, although none of them were significant (P > 0.05). In addition, AMH levels were consistent with the results of gene expression. Testosterone hormone levels from 10 day-olds to adults were significantly increased in both study groups (P = 0.016). Conclusions: While AMH receptor expression was higher in experimental rats, their serum concentrations of AMH were decreased. Further researches with greater sample sizes and measurement of bioactive forms of hormones are recommended to confirm the findings of this study. PMID:25745494

  10. Plastic components affect the activation of the aryl hydrocarbon and the androgen receptor.

    PubMed

    Krüger, Tanja; Long, Manhai; Bonefeld-Jørgensen, Eva C

    2008-04-18

    Phenols and plasticizers are widely used in the plastic industry, in food packaging and to impart softness and flexibility to normally rigid plastic medical devices and children's toys. The effects on the aryl hydrocarbon receptor (AhR) and the androgen receptor (AR) were assessed using luciferase reporter gene assays of the following compounds: bisphenol A (BPA), 4-n-nonylphenol (nNP), 4-tert-octylphenol (tOP), bis(2-ethylhexyl) phthalate (DEHP), di-isononyl phthalate (DINP), diisodecyl phthalate (DIDP), di-n-octyl phthalate (DNOP), dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), 4-chloro-3-methylphenol (CMP), 2-phenylphenol (2-PP), 2,4-dichlorophenol (DCP), resorcinol and bis(2-ethylhexyl) adipate (DEHA). Furthermore, a mixture of selected compounds was tested at the no-observed-effect concentration (NOEC), the low-observed-effect concentration (LOEC) and the half-maximum-effect/inhibitory concentration (EC50/IC50) of the single chemicals. Both receptors were affected by BPA, nNP, BBP, CMP, DCP and resorcinol whereas DEHP, DIDP and DBP affected only the AhR and tOP and 2-PP antagonised the AR activity. The mixture was composed of 6 compounds, of which one compound weakly induced the AhR but all compounds antagonized the AR activation. Using the concentration addition principle additive effects were observed at the NOEC, LOEC and EC50/IC50 for both receptors. Our in vitro data suggest that the effect of a mixture depends on the concentration, character, potency and composition of the single mixture compounds and that also the combined effects of the compounds should be taken into consideration for risk assessment of human health. PMID:18294747

  11. Expression of Androgen Receptor in Estrogen Receptor–positive Breast Cancer

    PubMed Central

    Ziolkowski, Piotr; Grzebieniak, Zygmunt; Jelen, Michal; Bobinski, Piotr; Agrawal, Siddarth

    2016-01-01

    Objectives: The aim of the study was to estimate the implications of androgen receptor (AR) expression in estrogen receptor (ER)-positive subset of invasive breast carcinoma patients. Patients and Methods: We assessed the AR expression in a subset of 96 predominantly ER-positive invasive breast carcinomas and correlated this expression pattern with several clinical and pathologic parameters: histologic type and grade, tumor size, lymph node status, progesterone receptor (PgR) status, and human epidermal growth factor receptor type 2 (HER2) overexpression and evaluated the association of these parameters with 10-year survival using univariate and multivariate analyses. Data used for analysis were derived from medical records. Immunohistochemical analysis for AR, ER, PgR, and HER2 were carried out and semiquantitative evaluation of stainings was performed. Results: AR expression was demonstrated in 43.7% of patients. AR was significantly related to well-differentiated tumors and positive PgR/HER2 status. No statistical difference was demonstrated in AR expression in relation to tumor size, lymph node status, menopausal status, and tumor histologic type. AR expression was not an independent prognostic factor related to 10-year survival in ER-positive cancers. In multivariate analyses, older age at diagnosis, larger tumor size, and positive lymph node status were significantly associated with poorer 10-year survival. Conclusions: AR expression is significantly associated with ER/PgR/HER2 status and positively related to well-differentiated tumors. Although AR status in ER-positive cancers is not an independent prognostic factor, it might provide important additional information on prognosis and become a promising object for targeted therapy. PMID:26230371

  12. Fighting experience alters brain androgen receptor expression dependent on testosterone status

    PubMed Central

    Li, Cheng-Yu; Earley, Ryan L.; Huang, Shu-Ping; Hsu, Yuying

    2014-01-01

    Contest decisions are influenced by the outcomes of recent fights (winner–loser effects). Steroid hormones and serotonin are closely associated with aggression and therefore probably also play important roles in mediating winner–loser effects. In mangrove rivulus fish, Kryptolebias marmoratus, individuals with higher testosterone (T), 11-ketotestosterone and cortisol levels are more capable of winning, but titres of these hormones do not directly mediate winner–loser effects. In this study, we investigated the effects of winning/losing experiences on brain expression levels of the receptor genes for androgen (AR), oestrogen α/β (ERα/β), glucocorticoid (GR) and serotonin (5-HT1AR). The effect of contest experience on AR gene expression depended on T levels: repeated losses decreased, whereas repeated wins increased AR gene expression in individuals with low T but not in individuals with medium or high T levels. These results lend strong support for AR being involved in mediating winner–loser effects, which, in previous studies, were more detectable in individuals with lower T. Furthermore, the expression levels of ERα/β, 5-HT1AR and GR genes were higher in individuals that initiated contests against larger opponents than in those that did not. Overall, contest experience, underlying endocrine state and hormone and serotonin receptor expression patterns interacted to modulate contest decisions jointly. PMID:25320171

  13. Compartmentalization of androgen receptor protein–protein interactions in living cells

    PubMed Central

    van Royen, Martin E.; Cunha, Sónia M.; Brink, Maartje C.; Mattern, Karin A.; Nigg, Alex L.; Dubbink, Hendrikus J.; Verschure, Pernette J.; Trapman, Jan; Houtsmuller, Adriaan B.

    2007-01-01

    Steroid receptors regulate gene expression in a ligand-dependent manner by binding specific DNA sequences. Ligand binding also changes the conformation of the ligand binding domain (LBD), allowing interaction with coregulators via LxxLL motifs. Androgen receptors (ARs) preferentially interact with coregulators containing LxxLL-related FxxLF motifs. The AR is regulated at an extra level by interaction of an FQNLF motif in the N-terminal domain with the C-terminal LBD (N/C interaction). Although it is generally recognized that AR coregulator and N/C interactions are essential for transcription regulation, their spatiotemporal organization is largely unknown. We performed simultaneous fluorescence resonance energy transfer and fluorescence redistribution after photobleaching measurements in living cells expressing ARs double tagged with yellow and cyan fluorescent proteins. We provide evidence that AR N/C interactions occur predominantly when ARs are mobile, possibly to prevent unfavorable or untimely cofactor interactions. N/C interactions are largely lost when AR transiently binds to DNA, predominantly in foci partly overlapping transcription sites. AR coregulator interactions occur preferentially when ARs are bound to DNA. PMID:17420290

  14. Homology-modeled ligand-binding domains of medaka estrogen receptors and androgen receptors: A model system for the study of reproduction

    SciTech Connect

    Cui Jianzhou Shen Xueyan; Yan Zuowei; Zhao Haobin; Nagahama, Yoshitaka

    2009-02-27

    Estrogen and androgen and their receptors play critical roles in physiological processes such as sexual differentiation and development. Using the available structural models for the human estrogen receptors alpha and beta and androgen receptor as templates, we designed in silico agonist and antagonist models of medaka estrogen receptor (meER) alpha, beta-1, and beta-2, and androgen receptor (meAR) alpha and beta. Using these models, we studied (1) the structural relationship between the ligand-binding domains (LBDs) of ERs and ARs of human and medaka, and (2) whether medaka ER and AR can be potential models for studying the ligand-binding activities of various agonists and antagonists of these receptors by docking analysis. A high level of conservation was observed between the sequences of the ligand-binding domains of meER{alpha} and huER{alpha}, meER{beta}1 and huER{beta}, meER{beta}2, and huER{beta} with 62.8%, 66.4%, and 65.1% identity, respectively. The sequence conservation between meAR{alpha} and huAR, meAR{beta}, and huAR was found with 70.1% and 61.0% of identity, respectively. Thirty-three selected endocrine disrupting chemicals (EDCs), including both agonists and antagonists, were docked into the LBD of ER and AR, and the corresponding docking score for medaka models and human templates were calculated. In order to confirm the conservation of the overall geometry and the binding pocket, the backbone root mean square deviation (RMSD) for C{alpha} atoms was derived from the structure superposition of all 10 medaka homology models to the six human templates. Our results suggested conformational conservation between the ERs and ARs of medaka and human, Thus, medaka could be highly useful as a model system for studies involving estrogen and androgen interaction with their receptors.

  15. A pp32-retinoblastoma protein complex modulates androgen receptor-mediated transcription and associates with components of the splicing machinery

    SciTech Connect

    Adegbola, Onikepe; Pasternack, Gary R. . E-mail: gpastern@jhmi.edu

    2005-08-26

    We have previously shown pp32 and the retinoblastoma protein interact. pp32 and the retinoblastoma protein are nuclear receptor transcriptional coregulators: the retinoblastoma protein is a coactivator for androgen receptor, the major regulator of prostate cancer growth, while pp32, which is highly expressed in prostate cancer, is a corepressor of the estrogen receptor. We now show pp32 increases androgen receptor-mediated transcription and the retinoblastoma protein modulates this activity. Using affinity purification and mass spectrometry, we identify members of the pp32-retinoblastoma protein complex as PSF and nonO/p54nrb, proteins implicated in coordinate regulation of nuclear receptor-mediated transcription and splicing. We show that the pp32-retinoblastoma protein complex is modulated during TPA-induced K562 differentiation. Present evidence suggests that nuclear receptors assemble multiprotein complexes to coordinately regulate transcription and mRNA processing. Our results suggest that pp32 and the retinoblastoma protein may be part of a multiprotein complex that coordinately regulates nuclear receptor-mediated transcription and mRNA processing.

  16. Association of adverse childhood experiences, age of menarche, and adult reproductive behavior: does the androgen receptor gene play a role?

    PubMed

    Jorm, Anthony F; Christensen, Helen; Rodgers, Bryan; Jacomb, Patricia A; Easteal, Simon

    2004-02-15

    Previous research has reported associations between adverse childhood experiences, early menarche, and early sexual activity. One hypothesis to account for these findings is that an X-linked androgen receptor GGC-repeat polymorphism predisposes fathers to behaviors which include family abandonment and their daughters to earlier menarche and sexual activity and less stable relationships. Retrospective data relevant to this theory were examined from a community survey involving 3,702 women in the age groups 20-24, 40-44, and 60-64 years, and another involving 908 women aged 18-79 years. Earlier age of menarche was found to be associated with adverse childhood experiences and earlier sexual activity. However, the androgen receptor gene polymorphism was unrelated to adverse fathering behavior or to marital breakdown. PMID:14755454

  17. A Novel Mutation in Human Androgen Receptor Gene Causing Partial Androgen Insensitivity Syndrome in a Patient Presenting with Gynecomastia at Puberty.

    PubMed

    Koçyiğit, Cemil; Sarıtaş, Serdar; Çatlı, Gönül; Onay, Hüseyin; Dündar, Bumin Nuri

    2016-06-01

    Partial androgen insensitivity syndrome (PAIS) typically presents with micropenis, perineoscrotal hypospadias, and a bifid scrotum with descending or undescending testes and gynecomastia at puberty. It is an X-linked recessive disorder resulting from mutations in the androgen receptor (AR) gene. However, AR gene mutations are found in less than a third of PAIS cases. A 16-year-old boy was admitted with complaints of gynecomastia and sparse facial hair. Family history revealed male relatives from maternal side with similar clinical phenotype. His external genitalia were phenotypically male with pubic hair Tanner stage IV, penoscrotal hypospadias, and a bifid scrotum with bilateral atrophic testes. He had elevated gonadotropins with a normal testosterone level. Chromosome analysis revealed a 46,XY karyotype. Due to the family history suggesting a disorder of X-linked trait, PAIS was considered and molecular analysis of AR gene was performed. DNA sequence analysis revealed a novel hemizygous mutation p.T576I (c.1727C>T) in the AR gene. The diagnosis of PAIS is based upon clinical phenotype and laboratory findings and can be confirmed by detection of a defect in the AR gene. An accurate approach including a detailed family history suggesting an X-linked trait is an important clue for a quick diagnosis. PMID:27087292

  18. Discovery of 3-aryloxy-lactam analogs as potent androgen receptor full antagonists for treating castration resistant prostate cancer.

    PubMed

    Guo, Chuangxing; Kephart, Susan; Ornelas, Martha; Gonzalez, Javier; Linton, Angelica; Pairish, Mason; Nagata, Asako; Greasley, Samantha; Elleraas, Jeff; Hosea, Natilie; Engebretsen, Jon; Fanjul, Andrea N

    2012-01-15

    High throughput cell-based screening led to the identification of 3-aryloxy lactams as potent androgen receptor (AR) antagonists. Refinement of these leads to improve the ADME profile and remove residual agonism led to the discovery of 12, a potent full antagonist with greater oral bioavailability. Improvements in the ADME profile were realized by designing more ligand-efficient molecules with reduced molecular weights and lower lipophilicities. PMID:22197140

  19. The Expression of the Androgen Receptor and Estrogen Receptor 1 is Related to Sex Dimorphism in the Gerbil Prostate Development.

    PubMed

    Sanches, Bruno D A; Maldarine, Juliana S; Zani, Bruno C; Biancardi, Manoel F; Santos, Fernanda C A; Góes, Rejane M; Vilamaior, Patricia S L; Taboga, Sebastião R

    2016-08-01

    The development of the prostate gland in females has not yet been clearly elucidated, and the sexual dimorphism associated with such gland development in general is far from being understood. In the present study, we used tridimensional (3D) reconstructions and histochemical and immunohistochemical techniques to describe the sexual dimorphism and its causes in the early postnatal development of the prostate in male and female Mongolian gerbils (Meriones unguiculatus). We observed that the female prostate was smaller, had fewer branches throughout the development, and underwent differentiation earlier than that in males. Also, the expression of the estrogen receptor 1 (ESR1 or ER-alpha) and fibroblast growth factor 10 (FGF10) was decreased in the periductal region, and the expression of the androgen receptor (AR) was increased in the epithelium. All together, these changes decreased proliferation and branching and led to an earlier prematuration of the female prostate. These new data shed light on the underlying mechanisms involved with the sexual dimorphism in the development of the prostate. Anat Rec, 299:1130-1139, 2016. © 2016 Wiley Periodicals, Inc. PMID:27184581

  20. Androgen receptor polyglutamine tract length in Egyptian male breast cancer patients.

    PubMed

    Gilbert, Samuel F; Soliman, Amr S; Iniesta, Maria; Eissa, Mohab; Hablas, Ahmed; Seifeldin, Ibrahim A; Strahley, Ashley; Banerjee, Mousumi; Merajver, Sofia D

    2011-09-01

    Male breast cancer (MBC) is a rare disease in the U.S., accounting for less than 1% of all breast cancers. Rates of MBC in Africa are more variable than in the U.S., therefore, understanding the risk factors involved in a population like Egypt can clarify the nature of MBC. The polyglutamine tract (QT) is a variable region of the androgen receptor (AR), a nuclear receptor which is important in modulating androgen actions and generally inhibits growth in breast tissue. It is hypothesized that a long QT results in weaker AR activity over the lifetime, resulting in less AR mediated control over cellular division and higher risk of MBC. As a corollary, we expect to see a distribution skewed toward longer QTs in MBC patients compared to controls and overall relatively longer QT's in populations with higher rates of MBC. This study aimed to investigate for the first time the distribution of AR QT lengths among MBC patients in Egypt. Paraffin-embedded tumor tissues from 44 Egyptian MBC patients were analyzed for this polymorphism. Amplification followed by fragment length analysis revealed QT length. For the control series, blood from 43 Egyptian males without a family or personal history of breast or prostate cancers was collected and analyzed similarly. There was no significant difference between patients and controls with respect to mean QT length (P = 0.84; means were 19.5 ± 2.8 and 19.3 ± 4.2, for patients and controls, respectively). Though, short QT lengths were more prevalent among controls (14.0%), but almost absent in cases (2.3%). Although the mean lengths were not different in cases and controls, the near absence of short tracts in cases suggests a possible protective effect of very short QT lengths against MBC. In populations in which there is variable incidence of MBC by region, investigations of the distribution of AR QT lengths are warranted to further delineate its role as a risk factor in MBC. PMID:21505847

  1. Downscaling procedures reduce chemical use in androgen receptor reporter gene assay.

    PubMed

    Di Paolo, Carolina; Kirchner, Kristina; Balk, Fabian Gerhard Peter; Muschket, Matthias; Brack, Werner; Hollert, Henner; Seiler, Thomas-Benjamin

    2016-11-15

    Bioactivity screening studies often face sample amount limitation with respect to the need for reliable, reproducible and quantitative results. Therefore approaches that minimize sample use are needed. Low-volume exposure and chemical dilution procedures were applied in an androgen receptor reporter gene human cell line assay to evaluate environmental contaminants and androgen receptor modulators, which were the agonist 5α-dihydrotestosterone (DHT); and the antagonists flutamide, bisphenol A, 1-hydroxypyrene and triclosan. Cells were exposed in around 1/3 of the medium volume recommended by the protocol (70μL/well). Further, chemical losses during pipetting steps were minimized by applying a low-volume method for compound dilution in medium (250μL for triplicate wells) inside microvolume glass inserts. Simultaneously, compounds were evaluated following conventional procedures (200μL/well, dilution in 24-well plates) for comparison of results. Low-volume exposure tests produced DHT EC50 (3.4-3.7×10(-10)M) and flutamide IC50 (2.2-3.3×10(-7)M) values very similar to those from regular assays (3.1-4.2×10(-10) and 2.1-3.3×10(-7)M respectively) and previous studies. Also, results were within assay acceptance criteria, supporting the relevance of the downscaling setup for agonistic and antagonistic tests. The low-volume exposure was also successful in determining IC50 values for 1-hydroxypyrene (2.1-2.8×10(-6)M), bisphenol A (2.6-3.3×10(-6)M), and triclosan (1.2-1.9×10(-6)M) in agreement with values obtained through high-volume exposure (2.3-2.8, 2.5-3.4 and 1.0-1.3×10(-6)M respectively). Finally, experiments following both low-volume dosing and exposure produced flutamide and triclosan IC50 values similar to those from regular tests. The low-volume experimental procedures provide a simple and effective solution for studies that need to minimize bioassay sample use while maintaining method reliability. The downscaling methods can be applied for the evaluation

  2. New therapy via targeting androgen receptor in monocytes/macrophages to battle atherosclerosis.

    PubMed

    Huang, Chiung-Kuei; Pang, Haiyan; Wang, Lin; Niu, Yuanjie; Luo, Jie; Chang, Eugene; Sparks, Janet D; Lee, Soo Ok; Chang, Chawnshang

    2014-06-01

    The male sex has a higher risk to develop coronary artery diseases, including atherosclerosis. The androgen receptor (AR) is expressed in several atherosclerosis-associated cell types, including monocytes/macrophages, endothelial cells (ECs), and smooth muscle cells (SMCs), but its pathophysiological role in each cell type during the development of atherosclerotic lesions remains unclear. Using the Cre-loxP system, we selectively knocked out AR in these 3 cell types and the resultant AR knockout (ARKO) mice, monocyte/macrophage ARKO, EC-ARKO, and SMC-ARKO, were then crossed with the low-density lipoprotein receptor (LDLR) deficient (LDLR(-/-)) mice to develop monocyte/macrophage ARKO-LDLR(-/-), EC-ARKO-LDLR(-/-), and SMC-ARKO-LDLR(-/-) mice for the study of atherosclerosis. The results showed that the monocyte/macrophage ARKO-LDLR(-/-) mice had reduced atherosclerosis compared with the wild-type-LDLR(-/-) control mice. However, no significant difference was detected in EC-ARKO-LDLR(-/-) and SMC-ARKO-LDLR(-/-) mice compared with wild-type-LDLR(-/-) mice, suggesting that the AR in monocytes/macrophages, and not in ECs and SMCs, plays a major role to promote atherosclerosis. Molecular mechanism dissection suggested that AR in monocytes/macrophages upregulated the tumor necrosis factor-α, integrin β2, and lectin-type oxidized LDL receptor 1 molecules that are involved in 3 major inflammation-related processes in atherosclerosis, including monocytes/macrophages migration and adhesion to human umbilical vein ECs, and subsequent foam cell formation. Targeting AR via the AR degradation enhancer, ASC-J9, in wild-type-LDLR(-/-) mice showed similar effects as seen in monocyte/macrophage ARKO-LDLR(-/-) mice with little influence on lipid profile. In conclusion, the AR in monocytes/macrophages plays key roles in atherosclerosis and targeting AR with ASC-J9 may represent a new potential therapeutic approach to battle atherosclerosis. PMID:24688120

  3. Radiation-inactivation size of transformed and non-transformed androgen receptors.

    PubMed Central

    Turcotte, G; Beauregard, G; Potier, M; Chevalier, S

    1991-01-01

    The nucleic acid sequence of the androgen receptor (AR) gene predicts that the protein structure possesses DNA- and steroid-binding domains that show high degrees of sequence similarity with those of other steroid receptors. Since the steroid-binding domain of the AR corresponds to a 30 kDa portion of the protein, and the AR structure may be monomeric or hetero-oligomeric depending on its transformation state, we have herein determined the AR radiation-inactivation size (RIS) in relation to the molecular structure whose binding activity toward methyltrienolone (R1881) is abolished by a radiation 'hit'. Soluble fractions from whole canine prostatic tissue were used as a source of non-transformed AR. The AR transformation was induced by the addition of 0.6 M-KCl, and these preparations were used together with high-salt nuclear extracts as a source of transformed AR. To maximize the binding activity, molybdate and dithiothreitol were included during AR extraction. Receptor transformation was verified by modifications of both the sedimentation coefficients (from 7.5 S to 4.1 S on sucrose gradients) and molecular masses (from 260 kDa to 115 kDa by gel filtration). The RIS values of the non-transformed and transformed ARs were not statistically different: 92 +/- 19 kDa and 110 +/- 25 kDa respectively. In addition, the inactivation of AR binding activity by radiation was attributed to a loss of binding sites, with no significant change in the Kd. When benzoic acid, a free-electron scavenger, was added together with dithiothreitol before and after irradiation, no change in the RIS value was observed. Thus, in the canine prostate, the RIS value of the AR represents the monomeric protein, independently of its association with other proteins, and this value corresponds to that predicted by cloning studies and photoaffinity-labelling of AR. PMID:2018483

  4. No association between androgen or vitamin D receptor gene polymorphisms and risk of breast cancer.

    PubMed

    Dunning, A M; McBride, S; Gregory, J; Durocher, F; Foster, N A; Healey, C S; Smith, N; Pharoah, P D; Luben, R N; Easton, D F; Ponder, B A

    1999-11-01

    Endogenous hormone exposure is known to alter breast cancer susceptibility and genes responsive to such hormones are plausible candidates for predisposition genes. We have examined polymorphisms in genes for two members of the nuclear receptor superfamily which are expressed in breast tissue and known to moderate rates of cell proliferation in a case-control association study: the androgen receptor (AR) and the vitamin D receptor (VDR). We have used two series of Caucasian female breast cancer cases, one incident and one prevalent, and compared both with two sets of matched controls from the East Anglian region of Britain. Since the results are similar in the two series we have combined them. The AR poly[Gly](n) and poly[Gln](n) tracts were genotyped in a total of 508 female breast cancer cases and 426 controls. The VDR TaqI polymorphism was analysed in 951 cases and 627 controls drawn from the same population series. There were no significant differences between cases and controls for either the AR or VDR polymorphisms. Compared with individuals with two short alleles (<22 repeats) of the AR poly[Gln](n) tract, the odds ratios and 95% confidence intervals (95% CI) for individuals with one or two long alleles were 0.82 (95% CI 0.62-1.09) and 1.31 (95% CI 0.87-1.97), respectively. Heterozygotes and homozygotes for the VDR TaqI cutting site had odds ratios of 1.01 (95% CI 0.81-1.27) and 0.97 (95% CI 0.71-1.32), respectively. None of the AR or VDR polymorphisms investigated has a major effect on risk of breast cancer in the British population. PMID:10545416

  5. Clinical importance of androgen receptor in breast cancer patients treated with adjuvant tamoxifen monotherapy.

    PubMed

    Honma, Naoko; Horii, Rie; Iwase, Takuji; Saji, Shigehira; Younes, Mamoun; Ito, Yoshinori; Akiyama, Futoshi

    2012-02-01

    BACKGROUND: Despite many studies, the clinicopathological importance of the androgen receptor (AR) in breast cancer is not well established, and its significance as an independent predictor of clinical outcome is controversial. A large and systematic study is needed to address these issues. The aim of the present study was to elucidate whether AR has independent clinical value, examining its importance in a large and well-predefined patient group with a long follow-up period and complete clinicopathological data. METHODS: Archival materials of 403 invasive breast cancers from women treated with adjuvant tamoxifen monotherapy (median follow-up period 11.0 years) were subjected to immunohistochemical study using anti-AR monoclonal antibody. AR expression was compared with established clinicopathological factors, estrogen receptor (ER)-β expression, and clinical outcome. RESULTS: AR positivity was correlated with ER-α positivity, progesterone receptor positivity, ER-β positivity, and a lower nuclear grade. Patients with AR-positive carcinomas exhibited a significantly better clinical outcome than those with AR-negative carcinomas (P = 0.0165 for disease-free survival, P = 0.0344 for overall survival). Multivariate analysis did not yield significant differences in clinical outcome according to the AR status, whereas the ER-β status showed significant differences in multivariate analysis. CONCLUSIONS: Although, and in agreement with previous reports, AR positivity correlated with some established favorable prognostic factors and with ER-β positivity, AR was not an independent predictor of clinical outcome. Controversy regarding the value of AR as an independent predictor of clinical outcome may at least partly reflect the relatively limited power of AR in breast cancer. PMID:22302643

  6. Estrogen and androgen receptor activities of hydraulic fracturing chemicals and surface and ground water in a drilling-dense region

    USGS Publications Warehouse

    Kassotis, Christopher D.; Tillitt, Donald E.; Davis, J. Wade; Hormann, Anette M.; Nagel, Susan C.

    2014-01-01

    The rapid rise in natural gas extraction using hydraulic fracturing increases the potential for contamination of surface and ground water from chemicals used throughout the process. Hundreds of products containing more than 750 chemicals and components are potentially used throughout the extraction process, including more than 100 known or suspected endocrine-disrupting chemicals. We hypothesized thataselected subset of chemicalsusedin natural gas drilling operationsandalso surface and ground water samples collected in a drilling-dense region of Garfield County, Colorado, would exhibit estrogen and androgen receptor activities. Water samples were collected, solid-phase extracted, and measured for estrogen and androgen receptor activities using reporter gene assays in human cell lines. Of the 39 unique water samples, 89%, 41%, 12%, and 46% exhibited estrogenic, antiestrogenic, androgenic, and antiandrogenic activities, respectively. Testing of a subset of natural gas drilling chemicals revealed novel antiestrogenic, novel antiandrogenic, and limited estrogenic activities. The Colorado River, the drainage basin for this region, exhibited moderate levels of estrogenic, antiestrogenic, and antiandrogenic activities, suggesting that higher localized activity at sites with known natural gas–related spills surrounding the river might be contributing to the multiple receptor activities observed in this water source. The majority of water samples collected from sites in a drilling-dense region of Colorado exhibited more estrogenic, antiestrogenic, or antiandrogenic activities than reference sites with limited nearby drilling operations. Our data suggest that natural gas drilling operationsmayresult in elevated endocrine-disrupting chemical activity in surface and ground water.

  7. Establishment of a novel immortalized human prostatic epithelial cell line stably expressing androgen receptor and its application for the functional screening of androgen receptor modulators

    SciTech Connect

    Yu, Shan; Wang, Ming-Wei; Yao, Xiaoqiang; Chan, F.L.

    2009-05-15

    In this study, we developed a human prostatic epithelial cell line BPH-1-AR stably expressing AR by lentiviral transduction. Characterization by immunoblot and RT-PCR showed that AR was stably expressed in all representative BPH-1-AR clones. Androgen treatment induced a secretory differentiation phenotype in BPH-1-AR cells but suppressed their cell proliferation. Treatments with AR agonists induced transactivation of a transfected PSA-gene promoter reporter in BPH-1-AR cells, whereas this transactivation was suppressed by an AR antagonist flutamide, indicating that the transduced AR in BPH-1-AR cells was functional. Finally, we utilized BPH-1-AR cells to evaluate the androgenic activities and growth effects of five newly developed non-steroidal compounds. Results showed that these compounds showed androgenic activities and growth-inhibitory effects on BPH-1-AR cells. Our results showed that BPH-1-AR cell line would be a valuable in vitro model for the study of androgen-regulated processes in prostatic epithelial cells and identification of compounds with AR-modulating activities.

  8. Monocyte/macrophage androgen receptor suppresses cutaneous wound healing in mice by enhancing local TNF-alpha expression.

    PubMed

    Lai, Jiann-Jyh; Lai, Kuo-Pao; Chuang, Kuang-Hsiang; Chang, Philip; Yu, I-Chen; Lin, Wen-Jye; Chang, Chawnshang

    2009-12-01

    Cutaneous wounds heal more slowly in elderly males than in elderly females, suggesting a role for sex hormones in the healing process. Indeed, androgen/androgen receptor (AR) signaling has been shown to inhibit cutaneous wound healing. AR is expressed in several cell types in healing skin, including keratinocytes, dermal fibroblasts, and infiltrating macrophages, but the exact role of androgen/AR signaling in these different cell types remains unclear. To address this question, we generated and studied cutaneous wound healing in cell-specific AR knockout (ARKO) mice. General and myeloid-specific ARKO mice exhibited accelerated wound healing compared with WT mice, whereas keratinocyte- and fibroblast-specific ARKO mice did not. Importantly, the rate of wound healing in the general ARKO mice was dependent on AR and not serum androgen levels. Interestingly, although dispensable for wound closure, keratinocyte AR promoted re-epithelialization, while fibroblast AR suppressed it. Further analysis indicated that AR suppressed wound healing by enhancing the inflammatory response through a localized increase in TNF-alpha expression. Furthermore, AR enhanced local TNF-alpha expression via multiple mechanisms, including increasing the inflammatory monocyte population, enhancing monocyte chemotaxis by upregulating CCR2 expression, and enhancing TNF-alpha expression in macrophages. Finally, targeting AR by topical application of a compound (ASC-J9) that degrades AR protein resulted in accelerated healing, suggesting a potential new therapeutic approach that may lead to better treatment of wound healing. PMID:19907077

  9. A transcriptional target of androgen receptor, miR-421 regulates proliferation and metabolism of prostate cancer cells.

    PubMed

    Meng, Delong; Yang, Shu; Wan, Xuechao; Zhang, Yalong; Huang, Wenhua; Zhao, Peiqing; Li, Tao; Wang, Lianqing; Huang, Yan; Li, Tao; Li, Yao

    2016-04-01

    Prostate cancer is one of the most common malignancies, and microRNAs have been recognized to be involved in tumorigenesis of various kinds of cancer including prostate cancer (PCa). Androgen receptor (AR) plays a core role in prostate cancer progression and is responsible for regulation of numerous downstream targets including microRNAs. This study identified an AR-repressed microRNA, miR-421, in prostate cancer. Expression of miR-421 was significantly suppressed by androgen treatment, and correlated to AR expression in different prostate cancer cell lines. Furthermore, androgen-activated AR could directly bind to androgen responsive element (ARE) of miR-421, as predicted by bioinformatics resources and demonstrated by ChIP and luciferase reporter assays. In addition, over-expression of miR-421 markedly supressed cell viability, delayed cell cycle, reduced glycolysis and inhibited migration in prostate cancer cells. According to the result of miR-421 target genes searching, we focused on 4 genes NRAS, PRAME, CUL4B and PFKFB2 based on their involvement in cell proliferation, cell cycle progression and metabolism. The expression of these 4 downstream targets were significantly repressed by miR-421, and the binding sites were verified by luciferase assay. Additionally, we explored the expression of miR-421 and its target genes in human prostate cancer tissues, both in shared microarray data and in our own cohort. Significant differential expression and inverse correlation were found in PCa patients. PMID:26827675

  10. SUMO ligase PIAS1 functions as a target gene selective androgen receptor coregulator on prostate cancer cell chromatin.

    PubMed

    Toropainen, Sari; Malinen, Marjo; Kaikkonen, Sanna; Rytinki, Miia; Jääskeläinen, Tiina; Sahu, Biswajyoti; Jänne, Olli A; Palvimo, Jorma J

    2015-01-01

    Androgen receptor (AR) is a ligand-activated transcription factor that plays a central role in the development and growth of prostate carcinoma. PIAS1 is an AR- and SUMO-interacting protein and a putative transcriptional coregulator overexpressed in prostate cancer. To study the importance of PIAS1 for the androgen-regulated transcriptome of VCaP prostate cancer cells, we silenced its expression by RNAi. Transcriptome analyses revealed that a subset of the AR-regulated genes is significantly influenced, either activated or repressed, by PIAS1 depletion. Interestingly, PIAS1 depletion also exposed a new set of genes to androgen regulation, suggesting that PIAS1 can mask distinct genomic loci from AR access. In keeping with gene expression data, silencing of PIAS1 attenuated VCaP cell proliferation. ChIP-seq analyses showed that PIAS1 interacts with AR at chromatin sites harboring also SUMO2/3 and surrounded by H3K4me2; androgen exposure increased the number of PIAS1-occupying sites, resulting in nearly complete overlap with AR chromatin binding events. PIAS1 interacted also with the pioneer factor FOXA1. Of note, PIAS1 depletion affected AR chromatin occupancy at binding sites enriched for HOXD13 and GATA motifs. Taken together, PIAS1 is a genuine chromatin-bound AR coregulator that functions in a target gene selective fashion to regulate prostate cancer cell growth. PMID:25552417

  11. SUMO ligase PIAS1 functions as a target gene selective androgen receptor coregulator on prostate cancer cell chromatin

    PubMed Central

    Toropainen, Sari; Malinen, Marjo; Kaikkonen, Sanna; Rytinki, Miia; Jääskeläinen, Tiina; Sahu, Biswajyoti; Jänne, Olli A.; Palvimo, Jorma J.

    2015-01-01

    Androgen receptor (AR) is a ligand-activated transcription factor that plays a central role in the development and growth of prostate carcinoma. PIAS1 is an AR- and SUMO-interacting protein and a putative transcriptional coregulator overexpressed in prostate cancer. To study the importance of PIAS1 for the androgen-regulated transcriptome of VCaP prostate cancer cells, we silenced its expression by RNAi. Transcriptome analyses revealed that a subset of the AR-regulated genes is significantly influenced, either activated or repressed, by PIAS1 depletion. Interestingly, PIAS1 depletion also exposed a new set of genes to androgen regulation, suggesting that PIAS1 can mask distinct genomic loci from AR access. In keeping with gene expression data, silencing of PIAS1 attenuated VCaP cell proliferation. ChIP-seq analyses showed that PIAS1 interacts with AR at chromatin sites harboring also SUMO2/3 and surrounded by H3K4me2; androgen exposure increased the number of PIAS1-occupying sites, resulting in nearly complete overlap with AR chromatin binding events. PIAS1 interacted also with the pioneer factor FOXA1. Of note, PIAS1 depletion affected AR chromatin occupancy at binding sites enriched for HOXD13 and GATA motifs. Taken together, PIAS1 is a genuine chromatin-bound AR coregulator that functions in a target gene selective fashion to regulate prostate cancer cell growth. PMID:25552417

  12. Expression of androgen receptor in non-muscle-invasive bladder cancer predicts the preventive effect of androgen deprivation therapy on tumor recurrence

    PubMed Central

    Miyamoto, Hiroshi; Miyoshi, Yasuhide; Ota, Junichi; Moriyama, Masatoshi; Murai, Tetsuo; Hayashi, Hiroyuki; Inayama, Yoshiaki; Ohashi, Kenichi; Yao, Masahiro; Uemura, Hiroji

    2016-01-01

    Our recent retrospective study revealed a significantly reduced risk of bladder cancer (BC) recurrence in men who received androgen deprivation therapy (ADT) for their prostate cancer. However, whether androgen receptor (AR) signals contributed to the preventive effect of ADT remained unclear because ADT could reduce serum estrogens as well. The purpose of this study is to investigate the associations between the expression of AR/estrogen receptors (ERs) and BC recurrence in patients treated with ADT. We immunohistochemically stained 72 BCs and 42 corresponding normal urothelial tissues. AR/ERα/ERβ were positive in 44(61%)/22(31%)/39(54%) tumors and 35(83%)/24(57%)/34(81%) corresponding normal urothelial tissues, respectively. There were no statistically significant correlations between AR/ERα/ERβ expression and clinicopathological features of BC. With a median follow-up of 31.3 months, 12 (43%) of 28 patients with AR-negative tumor versus 11 (23%) of 44 patients with AR-positive tumor experienced BC recurrence. Thus, patients with AR-positive tumor had a significantly lower risk of BC recurrence (P=0.031), compared with those with AR-negative tumor. Meanwhile, the expression of ERα/ERβ in tumors and that of AR/ERα/ERβ in normal urothelial tissues were not significantly correlated with BC recurrence. A multivariate analysis revealed AR positivity in tumors as an independent prognosticator (hazard ratio: 0.27; 95% confidence interval: 0.11-0.67) for BC recurrence. These results indicate that ADT prevents BC recurrence via the AR pathway, but not via the ERα/ERβ pathways. PMID:26885620

  13. Disruption of androgen and estrogen receptor activity in prostate cancer by a novel dietary diterpene carnosol: implications for chemoprevention

    PubMed Central

    Johnson, Jeremy J.; Syed, Deeba N.; Suh, Yewseok; Heren, Chenelle R.; Saleem, Mohammad; Siddiqui, Imtiaz A.; Mukhtar, Hasan

    2010-01-01

    Emerging data is suggesting that estrogens, in addition to androgens, may also be contributing to the development of prostate cancer (PCa). In view of this notion agents that target estrogens, in addition to androgens, may be a novel approach for PCa chemoprevention and treatment. Thus, the identification and development of non-toxic dietary agents capable of disrupting androgen receptor (AR) in addition to estrogen receptor (ER) could be extremely useful in the management of PCa. Through molecular modeling we found carnosol, a dietary diterpene fits within the ligand binding domain of both AR and ER-α. Using a TR-FRET assay we found that carnosol interacts with both AR and ER-α and additional experiments confirmed that it functions as a receptor antagonist with no agonist effects. LNCaP, 22Rv1, and MCF7 cells treated with carnosol (20–40 µM) showed decreased protein expression of AR and ER-α. Oral administration of carnosol at 30 mg/kg five days weekly for 28 days to 22Rv1 PCa xenografted mice suppressed tumor growth by 36% (p = 0.028) and was associated with a decrease in serum PSA by 26% (p=0.0042). These properties make carnosol unique to any known anti-androgen or anti-estrogen investigated so far for the simultaneous disruption of AR and ER-α. We suggest that carnosol may be developed or chemically modified through more rigorous structure activity relationship studies for a new class of investigational agents - a dual AR/ER modulator. PMID:20736335

  14. Chronic Blockade of the Androgen Receptor Abolishes Age-Dependent Increases in Blood Pressure in Female Growth-Restricted Rats.

    PubMed

    Dasinger, John Henry; Intapad, Suttira; Rudsenske, Benjamin R; Davis, Gwendolyn K; Newsome, Ashley D; Alexander, Barbara T

    2016-06-01

    Intrauterine growth restriction induced via placental insufficiency programs a significant increase in blood pressure at 12 months of age in female growth-restricted rats that is associated with early cessation of estrous cyclicity, indicative of premature reproductive senescence. In addition, female growth-restricted rats at 12 months of age exhibit a significant increase in circulating testosterone with no change in circulating estradiol. Testosterone is positively associated with blood pressure after menopause in women. Thus, we tested the hypothesis that androgen receptor blockade would abolish the significant increase in blood pressure that develops with age in female growth-restricted rats. Mean arterial pressure was measured in animals pretreated with and without the androgen receptor antagonist, flutamide (8 mg/kg/day, SC for 2 weeks). Flutamide abolished the significant increase in blood pressure in growth-restricted rats relative to control at 12 months of age. To examine the mechanism(s) by which androgens contribute to increased blood pressure in growth-restricted rats, blood pressure was assessed in rats untreated or treated with enalapril (250 mg/L for 2 weeks). Enalapril eliminated the increase in blood pressure in growth-restricted relative to vehicle- and flutamide-treated controls. Furthermore, the increase in medullary angiotensin type 1 receptor mRNA expression was abolished in flutamide-treated growth-restricted relative to untreated counterparts and controls; cortical angiotensin-converting enzyme mRNA expression was reduced in flutamide-treated growth-restricted versus untreated counterparts. Thus, these data indicate that androgens, via activation of the renin-angiotensin system, are important mediators of increased blood pressure that develops by 12 months of age in female growth-restricted rats. PMID:27113045

  15. Gene Expression Profiling of Androgen Receptor Antagonists Flutamide and Vinclozolin in Zebrafish (Danio rerio) Gonads

    EPA Science Inventory

    The studies presented in this manuscript focus on characterization of genomic responses to anti-androgens in zebrafish (Danio rerio). Research of the effects of anti-androgens in fish has been characterized by a heavy reliance on apical endpoints, and molecular mechanisms of acti...

  16. Functional analysis of duplicated Symbiosis Receptor Kinase (SymRK) genes during nodulation and mycorrhizal infection in soybean (Glycine max).

    PubMed

    Indrasumunar, Arief; Wilde, Julia; Hayashi, Satomi; Li, Dongxue; Gresshoff, Peter M

    2015-03-15

    Association between legumes and rhizobia results in the formation of root nodules, where symbiotic nitrogen fixation occurs. The early stages of this association involve a complex of signalling events between the host and microsymbiont. Several genes dealing with early signal transduction have been cloned, and one of them encodes the leucine-rich repeat (LRR) receptor kinase (SymRK; also termed NORK). The Symbiosis Receptor Kinase gene is required by legumes to establish a root endosymbiosis with Rhizobium bacteria as well as mycorrhizal fungi. Using degenerate primer and BAC sequencing, we cloned duplicated SymRK homeologues in soybean called GmSymRKα and GmSymRKβ. These duplicated genes have high similarity of nucleotide (96%) and amino acid sequence (95%). Sequence analysis predicted a malectin-like domain within the extracellular domain of both genes. Several putative cis-acting elements were found in promoter regions of GmSymRKα and GmSymRKβ, suggesting a participation in lateral root development, cell division and peribacteroid membrane formation. The mutant of SymRK genes is not available in soybean; therefore, to know the functions of these genes, RNA interference (RNAi) of these duplicated genes was performed. For this purpose, RNAi construct of each gene was generated and introduced into the soybean genome by Agrobacterium rhizogenes-mediated hairy root transformation. RNAi of GmSymRKβ gene resulted in an increased reduction of nodulation and mycorrhizal infection than RNAi of GmSymRKα, suggesting it has the major activity of the duplicated gene pair. The results from the important crop legume soybean confirm the joint phenotypic action of GmSymRK genes in both mycorrhizal and rhizobial infection seen in model legumes. PMID:25617765

  17. Identification of Novel Steroidal Androgen Receptor Degrading Agents Inspired by Galeterone 3β-Imidazole Carbamate.

    PubMed

    Purushottamachar, Puranik; Kwegyir-Afful, Andrew K; Martin, Marlena S; Ramamurthy, Vidya P; Ramalingam, Senthilmurugan; Njar, Vincent C O

    2016-07-14

    Degradation of all forms of androgen receptors (ARs) is emerging as an advantageous therapeutic paradigm for the effective treatment of prostate cancer. In continuation of our program to identify and develop improved efficacious novel small-molecule agents designed to disrupt AR signaling through enhanced AR degradation, we have designed, synthesized, and evaluated novel C-3 modified analogues of our phase 3 clinical agent, galeterone (5). Concerns of potential in vivo stability of our recently discovered more efficacious galeterone 3β-imidazole carbamate (6) led to the design and synthesis of new steroidal compounds. Two of the 11 compounds, 3β-pyridyl ether (8) and 3β-imidazole (17) with antiproliferative GI50 values of 3.24 and 2.54 μM against CWR22Rv1 prostate cancer cell, are 2.75- and 3.5-fold superior to 5. In addition, compounds 8 and 17 possess improved (∼4-fold) AR-V7 degrading activities. Importantly, these two compounds are expected to be metabolically stable, making them suitable for further development as new therapeutics against all forms of prostate cancer. PMID:27437082

  18. Significance of androgen receptor and CD10 expression in cutaneous basal cell carcinoma and trichoepithelioma

    PubMed Central

    ASTARCI, HESNA M.; GURBUZ, GULFEM A.; SENGUL, DEMET; HUCUMENOGLU, SEMA; KOCER, UGUR; USTUN, HUSEYIN

    2015-01-01

    Differential diagnosis of trichoepithelioma (TE) and basal cell carcinoma (BCC) on the basis of clinical symptoms and laboratory investigations may be difficult in certain patients. The aim of the present study was to compare cluster of differentiation 10 (CD10) and androgen receptor (AR) expression patterns in BCC and TE, to investigate the predictive power of these proteins as markers of the two conditions. A total of 39 cases of BCC and 15 cases of TE were retrieved from the pathology department archives. AR and CD10 immunohistochemistry was performed on all of the specimens; 23 BCC cases displayed focal nuclear AR staining, however, none of the cases demonstrated diffuse nuclear staining and 16 BCC cases were negative for AR staining. Stromal CD10 staining was more common in TE cases than in BCC cases, and peripheral CD10 staining was more common in BCC cases than in TE cases. AR immunostaining of the BCC samples typically appeared as scattered clusters and individual cells. In addition, AR and CD10 staining exhibited varying staining intensities within each samples. Incisional punch biopsy specimens have the potential to present false-negative results. Therefore, AR and CD10 staining of total excision biopsies provides a more accurate differential diagnosis of BCC and TE for cases with difficulties in the histopathological analysis. PMID:26788151

  19. Androgen receptor (CAG)n polymorphisms and breast cancer risk in a Han Chinese population.

    PubMed

    Dang, J; Peng, L; Zhong, H J; Huo, Z H

    2015-01-01

    The androgen receptor (AR) is involved in the differentiation and growth of breast cancer. Genetic markers in the AR gene have a plausible role in modulating the risk of breast cancer. In this study, we studied the association of breast cancer and the trinucleotide repeat polymorphism (CAG)n in exon 1 of the AR gene in 202 patients with breast cancer and 183 healthy controls from our hospital (Yinchuan, China). Repeat lengths were determined by fluorescent DNA fragment analysis using the ABI GeneScan software and DNA sequencing. We detected 17 short tandem repeat alleles in exon 1 in the Han population of Ningxia Province, China. The CAG repeat number ranged from 14 to 31 and the frequency ranged from 0.339 to 24.460%. Generally, (CAG)n repeat lengths <22 were classified as short (S), and those >22 were classified as long (L). No association was found between breast cancer and the S/L (CAG) variants. However, the frequency of the (CAG)25 repeats in the breast cancer group was significantly higher than that in the control group (P = 0.033, odds ratio = 1.790, 95% confidence interval = 1.044-3.069). These findings indicate a role for AR gene (CAG)n variations in breast cancer and might be informative for future genetic or biological studies on breast cancer, although these findings need replication in other populations. PMID:26345963

  20. Ligand fishing using new chitosan based functionalized Androgen Receptor magnetic particles.

    PubMed

    Marszałł, Michał Piotr; Sroka, Wiktor Dariusz; Sikora, Adam; Chełminiak, Dorota; Ziegler-Borowska, Marta; Siódmiak, Tomasz; Moaddel, Ruin

    2016-08-01

    Superparamagnetic nanoparticles with chemically modified chitosan has been proposed as a potential support for the immobilization of the androgen receptor (AR). The study involved comparison of different AR carriers like commercially available magnetic beads coated with silica (BcMag) and chitosan coated nanoparticles with different amount of amino groups. The immobilization was carried out through covalent immobilization of the AR through the terminal amino group or through available carboxylic acids. The initial characterization of the AR coated magnetic beads was carried out with dihydrotestosterone, a known AR ligand. Subsequently, chitosan modified nanporticles with long-distanced primary amino groups (Fe3O4CS-(NH2)3) (upto 8.34mM/g) were used for further study to isolate known AR ligands (bicalutamide, flutamide, hydroxyflutamide and levonogestrel) from a mixture of tested compounds in ammonium acetate buffer [10mM, pH 7.4]. The results showed that the selected nanoparticles are a promising semi-quantitative tool for the identification of high affinity compounds to AR and might be of special importance in the identification of novel agonists or antiandrogens. PMID:27156644

  1. Androgen Receptors Expression in Pituitary of Male Viscacha in relation to Growth and Reproductive Cycle

    PubMed Central

    Filippa, Verónica Palmira; Rosales, Gabriela Judith; Cruceño, Albana Andrea Marina; Mohamed, Fabian Heber

    2015-01-01

    The aim of this work was to study the androgen receptors (AR) expression in pituitary pars distalis (PD) of male viscachas in relation to growth and reproductive cycle. AR were detected by immunocytochemistry and quantified by image analysis. Pituitary glands from fetus, immature, prepubertal, and adult viscachas during their reproductive cycle were used. In the fetal PD, the immunoreactivity (ir) was mainly cytoplasmic. In immature and prepubertal animals, AR-ir was cytoplasmic (ARc-ir) and nuclear (ARn-ir) in medial region. In adult animals, ARn-ir cells were numerous at caudal end. AR regionalization varied between the PD zones in relation to growth. In immature animals, the ARn-ir increased whereas the cytoplasmic expression decreased in relation to the fetal glands. The percentage of ARc-ir cells increased in prepubertal animals whereas the nuclear AR expression was predominant in adult viscachas. The AR expression changed in adults, showing minimum percentage in the gonadal regression period. The variation of nuclear AR expression was directly related with testosterone concentration. These results demonstrated variations in the immunostaining pattern, regionalization, and number of AR-ir cells throughout development, growth, and reproductive cycle, suggesting the involvement of AR in the regulation of the pituitary activity of male viscacha. PMID:25945090

  2. Curcumin analogues with high activity for inhibiting human prostate cancer cell growth and androgen receptor activation.

    PubMed

    Zhou, Dai-Ying; Ding, Ning; Du, Zhi-Yun; Cui, Xiao-Xing; Wang, Hong; Wei, Xing-Chuan; Conney, Allan H; Zhang, Kun; Zheng, Xi

    2014-09-01

    The androgen receptor (AR) has a critical role in prostate cancer development and progression. Several curcumin analogues (A10, B10, C10, E10 and F10) with different linker groups were investigated for their effects in human prostate cancer CWR‑22Rv1 and LNCaP cell lines. The ability of these compounds to inhibit testosterone (TT)‑ or dihydrotestosterone (DHT)‑induced AR activity was determined by an AR‑linked luciferase assay and by TT‑ or DHT‑induced expression of prostate specific antigen. Compounds F10 and E10 had stronger inhibitory effects on the growth of cultured CWR‑22Rv1 and LNCaP cell lines, and they also had enhanced stimulatory effects on apoptosis compared with curcumin and other curcumin analogues (A10, B10, C10) in CWR‑22Rv1 cells. E10 and F10 were more potent inhibitors of AR activity than curcumin, A10 and B10. The higher activities of E10 and F10 may be correlated with a heteroatom linker. The results indicate that one of the potential mechanisms for the anticancer effect of the curcumin analogues was inhibition of AR pathways in human prostate cancer cells. PMID:25060817

  3. Stromal androgen receptor regulates the composition of the microenvironment to influence prostate cancer outcome.

    PubMed

    Leach, Damien A; Need, Eleanor F; Toivanen, Roxanne; Trotta, Andrew P; Palethorpe, Helen M; Palenthorpe, Helen M; Tamblyn, David J; Kopsaftis, Tina; England, Georgina M; Smith, Eric; Drew, Paul A; Pinnock, Carole B; Lee, Peng; Holst, Jeff; Risbridger, Gail P; Chopra, Samarth; DeFranco, Donald B; Taylor, Renea A; Buchanan, Grant

    2015-06-30

    Androgen receptor (AR) signaling in stromal cells is important in prostate cancer, yet the mechanisms underpinning stromal AR contribution to disease development and progression remain unclear. Using patient-matched benign and malignant prostate samples, we show a significant association between low AR levels in cancer associated stroma and increased prostate cancer-related death at one, three and five years post-diganosis, and in tissue recombination models with primary prostate cancer cells that low stromal AR decreases castration-induced apoptosis. AR-regulation was found to be different in primary human fibroblasts isolated from adjacent to cancerous and non-cancerous prostate epithelia, and to represent altered activation of myofibroblast pathways involved in cell cycle, adhesion, migration, and the extracellular matrix (ECM). Without AR signaling, the fibroblast-derived ECM loses the capacity to promote attachment of both myofibroblasts and cancer cells, is less able to prevent cell-matrix disruption, and is less likely to impede cancer cell invasion. AR signaling in prostate cancer stroma appears therefore to alter patient outcome by maintaining an ECM microenvironment inhibitory to cancer cell invasion. This paper provides comprehensive insight into AR signaling in the non-epithelial prostate microenvironment, and a resource from which the prognostic and therapeutic implications of stromal AR levels can be further explored. PMID:25965833

  4. A unique mosaic Turner syndrome patient with androgen receptor gene derived marker chromosome.

    PubMed

    Kalkan, Rasime; Özdağ, Nermin; Bundak, Rüveyde; Çirakoğlu, Ayşe; Serakinci, Nedime

    2016-01-01

    Patients with Turner syndrome are generally characterized by having short stature with no secondary sexual characteristics. Some abnormalities, such as webbed neck, renal malformations (>50%) and cardiac defects (10%) are less common. The intelligence of these patients is considered normal. Non-mosaic monosomy X is observed in approximately 45% of postnatal patients with Turner syndrome and the rest of the patients have structural abnormalities or mosaicism involving 46,X,i(Xq), 45,X/46,XX, 45,X and other variants. The phenotype of 45,X/46,X,+mar individuals varies by the genetic continent and degree of the mosaicism. The gene content of the marker chromosome is the most important when correlating the phenotype with the genotype. Here we present an 11-year-old female who was referred for evaluation of her short stature and learning disabilities. Conventional cytogenetic investigation showed a mosaic 45,X/46,X,+mar karyotype. Fluorescence in situ hybridization showed that the marker chromosome originated from the X chromosome within the androgen receptor (AR) and X-inactive specific transcript (XIST) genes. Therefore, it is possible that aberrant activation of the marker chromosome, compromising the AR and XIST genes, may modify the Turner syndrome phenotype. PMID:26744914

  5. ERG signaling in prostate cancer is driven through PRMT5-dependent methylation of the Androgen Receptor

    PubMed Central

    Mounir, Zineb; Korn, Joshua M; Westerling, Thomas; Lin, Fallon; Kirby, Christina A; Schirle, Markus; McAllister, Gregg; Hoffman, Greg; Ramadan, Nadire; Hartung, Anke; Feng, Yan; Kipp, David Randal; Quinn, Christopher; Fodor, Michelle; Baird, Jason; Schoumacher, Marie; Meyer, Ronald; Deeds, James; Buchwalter, Gilles; Stams, Travis; Keen, Nicholas; Sellers, William R; Brown, Myles; Pagliarini, Raymond A

    2016-01-01

    The TMPRSS2:ERG gene fusion is common in androgen receptor (AR) positive prostate cancers, yet its function remains poorly understood. From a screen for functionally relevant ERG interactors, we identify the arginine methyltransferase PRMT5. ERG recruits PRMT5 to AR-target genes, where PRMT5 methylates AR on arginine 761. This attenuates AR recruitment and transcription of genes expressed in differentiated prostate epithelium. The AR-inhibitory function of PRMT5 is restricted to TMPRSS2:ERG-positive prostate cancer cells. Mutation of this methylation site on AR results in a transcriptionally hyperactive AR, suggesting that the proliferative effects of ERG and PRMT5 are mediated through attenuating AR’s ability to induce genes normally involved in lineage differentiation. This provides a rationale for targeting PRMT5 in TMPRSS2:ERG positive prostate cancers. Moreover, methylation of AR at arginine 761 highlights a mechanism for how the ERG oncogene may coax AR towards inducing proliferation versus differentiation. DOI: http://dx.doi.org/10.7554/eLife.13964.001 PMID:27183006

  6. The fungus Cunninghamella elegans can produce human and equine metabolites of selective androgen receptor modulators (SARMs).

    PubMed

    Rydevik, Axel; Thevis, Mario; Krug, Oliver; Bondesson, Ulf; Hedeland, Mikael

    2013-05-01

    1. Selective androgen receptor modulators (SARMs) are a group of substances that have potential to be used as doping agents in sports. Being a relatively new group not available on the open market means that no reference materials are commercially available for the main metabolites. In the presented study, the in vitro metabolism of SARMs by the fungus Cunninghamella elegans has been investigated with the purpose of finding out if it can produce relevant human and equine metabolites. 2. Three different SARMs, S1, S4 and S24, were incubated for 5 days with C. elegans. The samples were analysed both with and without sample pretreatment using ultra performance liquid chromatography coupled to high resolution mass spectrometry. 3. All the important phase I and some phase II metabolites from human and horse were formed by the fungus. They were formed through reactions such as hydroxylation, deacetylation, O-dephenylation, nitro-reduction, acetylation and sulfonation. 4. The study showed that the fungus produced relevant metabolites of the SARMs and thus can be used to mimic mammalian metabolism. Furthermore, it has the potential to be used for future production of reference material. PMID:23153056

  7. Pax6 represses androgen receptor-mediated transactivation by inhibiting recruitment of the coactivator SPBP.

    PubMed

    Elvenes, Julianne; Thomassen, Ernst Ivan Simon; Johnsen, Sylvia Sagen; Kaino, Katrine; Sjøttem, Eva; Johansen, Terje

    2011-01-01

    The androgen receptor (AR) has a central role in development and maintenance of the male reproductive system and in the etiology of prostate cancer. The transcription factor Pax6 has recently been reported to act as a repressor of AR and to be hypermethylated in prostate cancer cells. SPBP is a transcriptional regulator that previously has been shown to enhance the activity of Pax6. In this study we have identified SPBP to act as a transcriptional coactivator of AR. We also show that Pax6 inhibits SPBP-mediated enhancement of AR activity on the AR target gene probasin promoter, a repression that was partly reversed by increased expression of SPBP. Enhanced expression of Pax6 reduced the amount of SPBP associated with the probasin promoter when assayed by ChIP in HeLa cells. We mapped the interaction between both AR and SPBP, and AR and Pax6 to the DNA-binding domains of the involved proteins. Further binding studies revealed that Pax6 and SPBP compete for binding to AR. These results suggest that Pax6 represses AR activity by displacing and/or inhibiting recruitment of coactivators to AR target promoters. Understanding the mechanism for inhibition of AR coactivators can give rise to molecular targeted drugs for treatment of prostate cancer. PMID:21935435

  8. Pax6 Represses Androgen Receptor-Mediated Transactivation by Inhibiting Recruitment of the Coactivator SPBP

    PubMed Central

    Johnsen, Sylvia Sagen; Kaino, Katrine; Sjøttem, Eva; Johansen, Terje

    2011-01-01

    The androgen receptor (AR) has a central role in development and maintenance of the male reproductive system and in the etiology of prostate cancer. The transcription factor Pax6 has recently been reported to act as a repressor of AR and to be hypermethylated in prostate cancer cells. SPBP is a transcriptional regulator that previously has been shown to enhance the activity of Pax6. In this study we have identified SPBP to act as a transcriptional coactivator of AR. We also show that Pax6 inhibits SPBP-mediated enhancement of AR activity on the AR target gene probasin promoter, a repression that was partly reversed by increased expression of SPBP. Enhanced expression of Pax6 reduced the amount of SPBP associated with the probasin promoter when assayed by ChIP in HeLa cells. We mapped the interaction between both AR and SPBP, and AR and Pax6 to the DNA-binding domains of the involved proteins. Further binding studies revealed that Pax6 and SPBP compete for binding to AR. These results suggest that Pax6 represses AR activity by displacing and/or inhibiting recruitment of coactivators to AR target promoters. Understanding the mechanism for inhibition of AR coactivators can give rise to molecular targeted drugs for treatment of prostate cancer. PMID:21935435

  9. Stromal androgen receptor regulates the composition of the microenvironment to influence prostate cancer outcome

    PubMed Central

    Leach, Damien A.; Need, Eleanor F.; Toivanen, Roxanne; Trotta, Andrew P.; Palenthorpe, Helen M.; Tamblyn, David J.; Kopsaftis, Tina; England, Georgina M.; Smith, Eric; Drew, Paul A.; Pinnock, Carole B.; Lee, Peng; Holst, Jeff; Risbridger, Gail P.; Chopra, Samarth; DeFranco, Donald B.; Taylor, Renea A.; Buchanan, Grant

    2015-01-01

    Androgen receptor (AR) signaling in stromal cells is important in prostate cancer, yet the mechanisms underpinning stromal AR contribution to disease development and progression remain unclear. Using patient-matched benign and malignant prostate samples, we show a significant association between low AR levels in cancer associated stroma and increased prostate cancer-related death at one, three and five years post-diganosis, and in tissue recombination models with primary prostate cancer cells that low stromal AR decreases castration-induced apoptosis. AR-regulation was found to be different in primary human fibroblasts isolated from adjacent to cancerous and non-cancerous prostate epithelia, and to represent altered activation of myofibroblast pathways involved in cell cycle, adhesion, migration, and the extracellular matrix (ECM). Without AR signaling, the fibroblast-derived ECM loses the capacity to promote attachment of both myofibroblasts and cancer cells, is less able to prevent cell-matrix disruption, and is less likely to impede cancer cell invasion. AR signaling in prostate cancer stroma appears therefore to alter patient outcome by maintaining an ECM microenvironment inhibitory to cancer cell invasion. This paper provides comprehensive insight into AR signaling in the non-epithelial prostate microenvironment, and a resource from which the prognostic and therapeutic implications of stromal AR levels can be further explored. PMID:25965833

  10. A role for the androgen receptor in the sexual differentiation of the olfactory system in mice

    PubMed Central

    Bodo, Cristian

    2008-01-01

    Olfactory signals play a central role in the identification of a mating partner in rodents, and the behavioral response to these cues varies markedly between the sexes. As several other sexually dimorphic traits, this response is thought to differentiate as a result of exposure of the developing individual to gonadal steroids, but both the identity of the specific steroid signal and the neural structures targeted for differentiation on this particular case are largely unknown. The present review summarizes results obtained in our lab using genetic males affected by the testicular feminization syndrome (Tfm) as experimental model, and that led to the identification of a role for non-aromatized gonadal steroids acting through the androgen receptor (AR) in the differentiation of olfactory cues processing in mice. The existing literature about AR-mediated sexual differentiation of the CNS in animal models is discussed, along with potential targets for the action of non-aromatized gonadal steroids in either one of the subsystems that detect and process olfactory information in rodents. PMID:17915335

  11. Mechanism of Androgen Receptor Antagonism by Bicalutamide in the Treatment of Prostate Cancer

    PubMed Central

    Osguthorpe, D.J.; Hagler, A.T.

    2011-01-01

    The androgen receptor (AR) plays a key role in a regulating gene expression in a variety of tissues, including the prostate. In the latter role it is one of the primary targets in the development of new chemotherapeutics for treatment of prostate cancer, as well as being the target of the most widely prescribed current drug, bicalutamide (Bcu), for this disease. In view of it’s importance, and the absence of a crystal structure for any antagonist-AR complex, we have carried out a series of molecular dynamics based simulations of the AR-Bcu complex and quantum mechanical (QM) calculations of Bcu, to elucidate the structural basis for antagonism of this key target. The structures which emerge show that bicalutamide antagonizes AR by accessing an additional binding pocket (B-site) adjacent to the hormone binding site (HBS), induced by displacing helix 12. This distorts the coactivator binding site and results in the inactivation of transcription. An alternative equienergetic conformational state of bicalutamide was found to bind in an expanded hormone pocket without materially perturbing either helix 12 or the coactivator binding site. Thus both the structural basis of antagonism and the mechanism underlying agonist properties displayed by bicalutamide in different environments may be rationalized in terms of these structures. In addition the antagonist structure and especially the induced second site (B-site) provides a structural framework for the design of novel antiandrogens. PMID:21466228

  12. MiR-298 Counteracts Mutant Androgen Receptor Toxicity in Spinal and Bulbar Muscular Atrophy

    PubMed Central

    Pourshafie, Naemeh; Lee, Philip R; Chen, Ke-lian; Harmison, George G; Bott, Laura C; Katsuno, Masahisa; Sobue, Gen; Burnett, Barrington G; Fischbeck, Kenneth H; Rinaldi, Carlo

    2016-01-01

    Spinal and bulbar muscular atrophy (SBMA) is a currently untreatable adult-onset neuromuscular disease caused by expansion of a polyglutamine repeat in the androgen receptor (AR). In SBMA, as in other polyglutamine diseases, a toxic gain of function in the mutant protein is an important factor in the disease mechanism; therefore, reducing the mutant protein holds promise as an effective treatment strategy. In this work, we evaluated a microRNA (miRNA) to reduce AR expression. From a list of predicted miRNAs that target human AR, we selected microRNA-298 (miR-298) for its ability to downregulate AR mRNA and protein levels when transfected in cells overexpressing wild-type and mutant AR and in SBMA patient-derived fibroblasts. We showed that miR-298 directly binds to the 3'-untranslated region of the human AR transcript, and counteracts AR toxicity in vitro. Intravenous delivery of miR-298 with adeno-associated virus serotype 9 vector resulted in efficient transduction of muscle and spinal cord and amelioration of the disease phenotype in SBMA mice. Our findings support the development of miRNAs as a therapeutic strategy for SBMA and other neurodegenerative disorders caused by toxic proteins. PMID:26755334

  13. MiR-298 Counteracts Mutant Androgen Receptor Toxicity in Spinal and Bulbar Muscular Atrophy.

    PubMed

    Pourshafie, Naemeh; Lee, Philip R; Chen, Ke-Lian; Harmison, George G; Bott, Laura C; Katsuno, Masahisa; Sobue, Gen; Burnett, Barrington G; Fischbeck, Kenneth H; Rinaldi, Carlo

    2016-05-01

    Spinal and bulbar muscular atrophy (SBMA) is a currently untreatable adult-onset neuromuscular disease caused by expansion of a polyglutamine repeat in the androgen receptor (AR). In SBMA, as in other polyglutamine diseases, a toxic gain of function in the mutant protein is an important factor in the disease mechanism; therefore, reducing the mutant protein holds promise as an effective treatment strategy. In this work, we evaluated a microRNA (miRNA) to reduce AR expression. From a list of predicted miRNAs that target human AR, we selected microRNA-298 (miR-298) for its ability to downregulate AR mRNA and protein levels when transfected in cells overexpressing wild-type and mutant AR and in SBMA patient-derived fibroblasts. We showed that miR-298 directly binds to the 3'-untranslated region of the human AR transcript, and counteracts AR toxicity in vitro. Intravenous delivery of miR-298 with adeno-associated virus serotype 9 vector resulted in efficient transduction of muscle and spinal cord and amelioration of the disease phenotype in SBMA mice. Our findings support the development of miRNAs as a therapeutic strategy for SBMA and other neurodegenerative disorders caused by toxic proteins. PMID:26755334

  14. Abnormal Mitochondrial Function and Impaired Granulosa Cell Differentiation in Androgen Receptor Knockout Mice

    PubMed Central

    Wang, Ruey-Sheng; Chang, Heng-Yu; Kao, Shu-Huei; Kao, Cheng-Heng; Wu, Yi-Chen; Yeh, Shuyuan; Tzeng, Chii-Reuy; Chang, Chawnshang

    2015-01-01

    In the ovary, the paracrine interactions between the oocyte and surrounded granulosa cells are critical for optimal oocyte quality and embryonic development. Mice lacking the androgen receptor (AR−/−) were noted to have reduced fertility with abnormal ovarian function that might involve the promotion of preantral follicle growth and prevention of follicular atresia. However, the detailed mechanism of how AR in granulosa cells exerts its effects on oocyte quality is poorly understood. Comparing in vitro maturation rate of oocytes, we found oocytes collected from AR−/− mice have a significantly poor maturating rate with 60% reached metaphase II and 30% remained in germinal vesicle breakdown stage, whereas 95% of wild-type AR (AR+/+) oocytes had reached metaphase II. Interestingly, we found these AR−/− female mice also had an increased frequency of morphological alterations in the mitochondria of granulosa cells with reduced ATP generation (0.18 ± 0.02 vs. 0.29 ± 0.02 µM/mg protein; p < 0.05) and aberrant mitochondrial biogenesis. Mechanism dissection found loss of AR led to a significant decrease in the expression of peroxisome proliferator-activated receptor γ (PPARγ) co-activator 1-β (PGC1-β) and its sequential downstream genes, nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM), in controlling mitochondrial biogenesis. These results indicate that AR may contribute to maintain oocyte quality and fertility via controlling the signals of PGC1-β-mediated mitochondrial biogenesis in granulosa cells. PMID:25941928

  15. Associations between androgen and Vitamin D receptor microsatellites and postmenopausal breast cancer.

    PubMed

    Wedrén, Sara; Magnusson, Cecilia; Humphreys, Keith; Melhus, Håkan; Kindmark, Andreas; Stiger, Fredrik; Branting, Maria; Persson, Ingemar; Baron, John; Weiderpass, Elisabete

    2007-09-01

    We investigated the association between polymorphism in the androgen receptor (AR) and vitamin D receptor (VDR) genes and breast cancer risk in a large population-based case-control study of genetically homogenous Swedish women. We successfully determined both AR CAG(n) and VDR A(n) genotype in 1,502 women with invasive breast cancer and in 1,510 control women. We did not find any associations between AR or VDR microsatellite lengths and breast cancer when we used a priori determined cutoffs (/=22 repeats for AR and /=19 for VDR) to define long and short alleles. There was statistically significant interaction between VDR genotype and parity, such that women with two short alleles had a halved risk for breast cancer, irrespective of parity, compared with nulliparous women with two long alleles. Homozygosity for the long VDR allele was associated with a more advanced clinical stage at diagnosis. In exploratory analyses, we determined cutoffs based on visual inspection of distributions of allele lengths among cases and controls and found that women carrying two alleles with <20 AR CAG(n) repeats had an increased risk for breast cancer, odds ratio of 1.67 (95% confidence interval, 1.17-2.38), compared with those with two alleles with >/=20 repeats. Women carrying two VDR alleles with <21 A(n) were also at an increased risk, odds ratio of 1.26 (95% confidence interval, 1.04-1.51). Our data do not support major roles for AR or VDR polymorphism as breast cancer risk factors. However, we did find an interaction between VDR genotype and parity that remains to be corroborated. PMID:17855696

  16. Carbidopa abrogates L-dopa decarboxylase coactivation of the androgen receptor and delays prostate tumor progression.

    PubMed

    Wafa, Latif A; Cheng, Helen; Plaa, Nathan; Ghaidi, Fariba; Fukumoto, Takahiro; Fazli, Ladan; Gleave, Martin E; Cox, Michael E; Rennie, Paul S

    2012-06-15

    The androgen receptor (AR) plays a central role in prostate cancer progression to the castration-resistant (CR) lethal state. L-Dopa decarboxylase (DDC) is an AR coactivator that increases in expression with disease progression and is coexpressed with the receptor in prostate adenocarcinoma cells, where it may enhance AR activity. Here, we hypothesize that the DDC enzymatic inhibitor, carbidopa, can suppress DDC-coactivation of AR and retard prostate tumor growth. Treating LNCaP prostate cancer cells with carbidopa in transcriptional assays suppressed the enhanced AR transactivation seen with DDC overexpression and decreased prostate-specific antigen (PSA) mRNA levels. Carbidopa dose-dependently inhibited cell growth and decreased survival in LNCaP cell proliferation and apoptosis assays. The inhibitory effect of carbidopa on DDC-coactivation of AR and cell growth/survival was also observed in PC3 prostate cancer cells (stably expressing AR). In vivo studies demonstrated that serum PSA velocity and tumor growth rates elevated ∼2-fold in LNCaP xenografts, inducibly overexpressing DDC, were reverted to control levels with carbidopa administration. In castrated mice, treating LNCaP tumors, expressing endogenous DDC, with carbidopa delayed progression to the CR state from 6 to 10 weeks, while serum PSA and tumor growth decreased 4.3-fold and 5.4-fold, respectively. Our study is a first time demonstration that carbidopa can abrogate DDC-coactivation of AR in prostate cancer cells and tumors, decrease serum PSA, reduce tumor growth and delay CR progression. Since carbidopa is clinically approved, it may be readily used as a novel therapeutic strategy to suppress aberrant AR activity and delay prostate cancer progression. PMID:21780103

  17. A precisely substituted benzopyran targets androgen refractory prostate cancer cells through selective modulation of estrogen receptors.

    PubMed

    Kumar, Rajeev; Verma, Vikas; Sharma, Vikas; Jain, Ashish; Singh, Vishal; Sarswat, Amit; Maikhuri, Jagdamba P; Sharma, Vishnu L; Gupta, Gopal

    2015-03-15

    Dietary consumption of phytoestrogens like genistein has been linked with lower incidence of prostate cancer. The estradiol-like benzopyran core of genistein confers estrogen receptor-β (ER-β) selectivity that imparts weak anti-proliferative activity against prostate cancer cells. DL-2-[4-(2-piperidinoethoxy)phenyl]-3-phenyl-2H-1-benzopyran (BP), a SERM designed with benzopyran core, targeted androgen independent prostate cancer (PC-3) cells 14-times more potently than genistein, ~25% more efficiently than tamoxifen and 6.5-times more actively than ICI-182780, without forfeiting significant specificity in comparison to genistein. BP increased apoptosis (annexin-V and TUNEL labeling), arrested cell cycle, and significantly increased caspase-3 activity along with mRNA expressions of estrogen receptor (ER)-β and FasL (qPCR) in PC-3 cells. In classical ERE-luc reporter assay BP behaved as a potent ER-α antagonist and ER-β agonist. Accordingly, it decreased expression of ER-α target PS2 (P<0.01) and increased expression of ER-β target TNF-α (P<0.05) genes in PC-3. ER-β deficient PC-3 (siRNA-transfected) was resistant to apoptotic and anti-proliferative actions of SERMs, including stimulation of FasL expression by BP. BP significantly inhibited phosphorylation of Akt and ERK-1/2, JNK and p38 in PC-3 (immunoblotting), and thus adopted a multi-pathway mechanism to exert a more potent anti-proliferative activity against prostate cancer cells than natural and synthetic SERMs. Its precise ER-subtype specific activity presents a unique lead structure for further optimization. PMID:25655200

  18. The Androgen Receptor Regulates PPARγ Expression and Activity in Human Prostate Cancer Cells.

    PubMed

    Olokpa, Emuejevoke; Bolden, Adrienne; Stewart, LaMonica V

    2016-12-01

    The peroxisome proliferator activated receptor gamma (PPARγ) is a ligand-activated transcription factor that regulates growth and differentiation within normal prostate and prostate cancers. However the factors that control PPARγ within the prostate cancers have not been characterized. The goal of this study was to examine whether the androgen receptor (AR) regulates PPARγ expression and function within human prostate cancer cells. qRT-PCR and Western blot analyses revealed nanomolar concentrations of the AR agonist dihydrotestosterone (DHT) decrease PPARγ mRNA and protein within the castration-resistant, AR-positive C4-2 and VCaP human prostate cancer cell lines. The AR antagonists bicalutamide and enzalutamide blocked the ability of DHT to reduce PPARγ levels. In addition, siRNA mediated knockdown of AR increased PPARγ protein levels and ligand-induced PPARγ transcriptional activity within the C4-2 cell line. Furthermore, proteasome inhibitors that interfere with AR function increased the level of basal PPARγ and prevented the DHT-mediated suppression of PPARγ. These data suggest that AR normally functions to suppress PPARγ expression within AR-positive prostate cancer cells. To determine whether increases in AR protein would influence PPARγ expression and activity, we used lipofectamine-based transfections to overexpress AR within the AR-null PC-3 cells. The addition of AR to PC-3 cells did not significantly alter PPARγ protein levels. However, the ability of the PPARγ ligand rosiglitazone to induce activation of a PPARγ-driven luciferase reporter and induce expression of FABP4 was suppressed in AR-positive PC-3 cells. Together, these data indicate AR serves as a key modulator of PPARγ expression and function within prostate tumors. J. Cell. Physiol. 231: 2664-2672, 2016. © 2016 Wiley Periodicals, Inc. PMID:26945682

  19. Clinical verification of sensitivity to preoperative chemotherapy in cases of androgen receptor-expressing positive breast cancer

    PubMed Central

    Asano, Yuka; Kashiwagi, Shinichiro; Onoda, Naoyoshi; Kurata, Kento; Morisaki, Tamami; Noda, Satoru; Takashima, Tsutomu; Ohsawa, Masahiko; Kitagawa, Seiichi; Hirakawa, Kosei

    2016-01-01

    Background: Triple-negative breast cancer (TNBC) patients testing positive for androgen receptor (AR) expression are thought to be chemotherapy resistant, similar to other hormone receptor-positive breast cancers; however, this has not been substantially validated in the clinic. In this study, we investigated the association between chemotherapy sensitivity and AR expression in patients treated with neoadjuvant chemotherapy (NAC) using standardised chemotherapy criteria and regimens. Methods: A total of 177 patients with resectable early-stage breast cancer were treated with NAC. Oestrogen receptor, progesterone receptor, HER2, Ki67 and AR status were assessed immunohistochemically. Results: Sixty-one patients were diagnosed with TNBC; AR expression was identified in 23 (37.7%), which was significantly less common than that found in non-TNBC patients (103 of 116; 88.8% P<0.001). The rate of pathological complete response after NAC was significantly lower (P=0.001), and disease recurrence was more common (P=0.008) in patients with AR-positive compared with those with AR-negative TNBC. In TNBC cases, as expected, the non-recurrence period in cases that were negative for AR expression was significantly extended (P=0.006, log-rank). Conclusions: Androgen receptor expressions may be useful as biomarkers to predict treatment responses to NAC in TNBC. Moreover, induction of a change in subtype to the AR-negative phenotype was observed after NAC. PMID:26757422

  20. Registered report: the androgen receptor induces a distinct transcriptional program in castration-resistant prostate cancer in man

    PubMed Central

    Chronscinski, Denise; Cherukeri, Srujana; Tan, Fraser; Lomax, Joelle; Iorns, Elizabeth

    2015-01-01

    The Prostate Cancer Foundation-Movember Foundation Reproducibility Initiative (PCFMFRI) seeks to address growing concerns about reproducibility in scientific research by conducting replications of recent papers in the field of prostate cancer. This Registered Report describes the proposed replication plan of key experiments from “The Androgen Receptor Induces a Distinct Transcriptional Program in Castration-Resistant Prostate Cancer in Man” by Sharma and colleagues (2013), published in Cancer Cell in 2013. Of thousands of targets for the androgen receptor (AR), the authors elucidated a subset of 16 core genes that were consistently downregulated with castration and re-emerged with castration resistance. These 16 AR binding sites were distinct from those observed in cells in culture. The authors suggested that cellular context can have dramatic effects on downstream transcriptional regulation of AR binding sites. The present study will attempt to replicate Fig. 7C by comparing gene expression of the 16 core genes identified by Sharma and colleagues in xenograft tumor tissue compared to androgen treated LNCaP cells in vitro. The Prostate Cancer Foundation-Movember Foundation Reproducibility Initiative is a collaboration between the Prostate Cancer Foundation, the Movember Initiative, and Science Exchange, and the results of the replications will be published by PeerJ. PMID:26401447

  1. NKX3.1 Suppresses TMPRSS2-ERG Gene Rearrangement and Mediates Repair of Androgen Receptor-Induced DNA Damage

    PubMed Central

    Bowen, Cai; Zheng, Tian; Gelmann, Edward P.

    2015-01-01

    TMPRSS2 gene rearrangements occur at DNA breaks formed during androgen receptor-mediated transcription and activate expression of ETS transcription factors at the early stages of more than half of prostate cancers. NKX3.1, a prostate tumor suppressor that accelerates the DNA repair response, binds to androgen receptor at the ERG gene breakpoint and inhibits both the juxtaposition of the TMPRSS2 and ERG gene loci and also their recombination. NKX3.1 acts by accelerating DNA repair after androgen-induced transcriptional activation. NKX3.1 influences the recruitment of proteins that promote homology-directed DNA repair. Loss of NKX3.1 favors recruitment to the ERG gene breakpoint of proteins that promote error-prone nonhomologous end-joining. Analysis of prostate cancer tissues showed that the presence of a TMPRSS2-ERG rearrangement was highly correlated with lower levels of NKX3.1 expression consistent with the role of NKX3.1 as a suppressor of the pathogenic gene rearrangement. PMID:25977336

  2. Isolation and identification of ligands for the goldfish testis androgen receptor in chemical recovery condensates from a Canadian bleached kraft pulp and paper mill.

    PubMed

    Scott, Philip D; Milestone, Craig B; Smith, D Scott; MacLatchy, Deborah L; Hewitt, L Mark

    2011-12-01

    This study builds on a series of investigations characterizing substances in kraft mill chemical recovery condensates that depress sex steroids in fish. Here, incubations of goldfish testis androgen receptors (AR) with condensate extracts were used to investigate the potential role of androgens in hormone depressions. Condensates contained variable levels of AR ligands, with the highest amounts in nonpolar extracts of filtered solids prior to solid phase extraction (SPE). High pressure liquid chromatography (HPLC) fractionation recovered the majority of activity in one fraction, with ligands detected in three additional fractions. Gas chromatography mass spectrometry analysis of the most active fraction confirmed the two most abundant components as the diterpenes manool and geranyl linalool. Manool exhibited a relative affinity for the AR that was 300 fold less than testosterone and accounted for 26% of total filtered solids activity. Geranyl linalool exhibited no affinity for the AR. Three additional diterpenoid families were tentatively identified as principal components of the three other androgenic HPLC fractions. Compared to condensates, final effluent had 3000 fold less androgenic activity, with <1% attributable to manool. Putative androgens previously associated with mill effluents (androstenedione and androstadienedione) and progesterone were not detected; however, additional condensate diterpenes suspected as androgens were identified in final effluent. This study is the first to confirm nonsteroidal cyclic diterpenes as androgenic at pulp mills. A major in-mill source of these substances was identified, and the role of androgens in mill effluents affecting fish reproduction was reinforced. PMID:22040000

  3. An Integrated Network of Androgen Receptor, Polycomb, and TMPRSS2-ERG Gene Fusions in Prostate Cancer Progression

    PubMed Central

    Yu, Jindan; Yu, Jianjun; Mani, Ram-Shankar; Cao, Qi; Brenner, Chad J.; Cao, Xuhong; Wang, George X.; Wu, Longtao; Li, James; Hu, Ming; Gong, Yusong; Cheng, Hong; Laxman, Bharathi; Vellaichamy, Adaikkalam; Shankar, Sunita; Li, Yong; Dhanasekaran, Saravana M.; Morey, Roger; Barrette, Terrence; Lonigro, Robert J.; Tomlins, Scott A.; Varambally, Sooryanarayana; Qin, Zhaohui S.; Chinnaiyan, Arul M.

    2010-01-01

    SUMMARY While chromosomal rearrangements fusing the androgen-regulated gene TMPRSS2 to the oncogenic ETS transcription factor ERG occur in approximately 50% of prostate cancers, how the fusion products regulate prostate cancer remains unclear. Using chromatin immunoprecipitation coupled with massively parallel sequencing (ChIP-Seq), we found that ERG disrupts androgen receptor (AR) signaling by inhibiting AR expression, binding to and inhibiting AR activity at gene-specific loci, and inducing repressive epigenetic programs via direct activation of the H3K27 methyltransferase EZH2, a Polycomb group protein. These findings provide a working model in which TMPRSS2-ERG plays a critical role in cancer progression by disrupting lineage-specific differentiation of the prostate and potentiating the EZH2-mediated de-differentiation program. PMID:20478527

  4. The environmental endocrine disruptor p-nitrophenol interacts with FKBP51, a positive regulator of androgen receptor and inhibits androgen receptor signaling in human cells.

    PubMed

    Wu, Dan; Tao, Xuanyu; Chen, Zhi-Peng; Han, Jian-Ting; Jia, Wen-Juan; Zhu, Ning; Li, Xiangkai; Wang, Zhiping; He, Yong-Xing

    2016-04-15

    The compound p-nitrophenol, which shows the anti-androgenic activity, can easily become anthropogenic pollutants and pose a threat to the environment and human health. Previous work indicates that the anti-androgenic mechanism of p-nitrophenol is complex and may involve several components in the AR signaling pathway, but the molecular details of how p-nitrophenol inhibits AR signaling are still not quite clear. Here, we characterized p-nitrophenol binds to the FK1 domain of an AR positive regulator FKBP51 with micromolar affinity and structural analysis of FK1 domain in complex with p-nitrophenol revealed that p-nitrophenol occupies a hydrophobic FK1 pocket that is vital for AR activity enhancement. Molecular dynamics simulation indicated that p-nitrophenol is stably bound to the FK1 pocket and the hotspot residues that involved p-nitrophenol binding are mainly hydrophobic and overlap with the AR interaction site. Furthermore, we showed that p-nitrophenol inhibits the androgen-dependent growth of human prostate cancer cells, possibly through down-regulating the expression levels of AR activated downstream genes. Taken together, our data suggests that p-nitrophenol suppresses the AR signaling pathway at least in part by blocking the interaction between AR and its positive regulator FKBP51. We believe that our findings could provide new guidelines for assessing the potential health effects of p-nitrophenol. PMID:26780698

  5. Molecular cloning of canine co-chaperone small glutamine-rich tetratricopeptide repeat-containing protein α (SGTA) and investigation of its ability to suppress androgen receptor signalling in androgen-independent prostate cancer.

    PubMed

    Kato, Yuiko; Ochiai, Kazuhiko; Michishita, Masaki; Azakami, Daigo; Nakahira, Rei; Morimatsu, Masami; Ishiguro-Oonuma, Toshina; Yoshikawa, Yasunaga; Kobayashi, Masato; Bonkobara, Makoto; Kobayashi, Masanori; Takahashi, Kimimasa; Watanabe, Masami; Omi, Toshinori

    2015-11-01

    Although the morbidity of canine prostate cancer is low, the majority of cases present with resistance to androgen therapy and poor clinical outcomes. These pathological conditions are similar to the signs of the terminal stage of human androgen-independent prostate cancer. The co-chaperone small glutamine-rich tetratricopeptide repeat-containing protein α (SGTA) is known to be overexpressed in human androgen-independent prostate cancer. However, there is little information about the structure and function of canine SGTA. In this study, canine SGTA was cloned and analysed for its ability to suppress androgen receptor signalling. The full-length open reading frame (ORF) of the canine SGTA gene was amplified by RT-PCR using primers designed from canine-expressed sequence tags that were homologous to human SGTA. The canine SGTA ORF has high homology with the corresponding human (89%) and mouse (81%) sequences. SGTA dimerisation region and tetratricopeptide repeat (TPR) domains are conserved across the three species. The ability of canine SGTA to undergo homodimerisation was demonstrated by a mammalian two-hybrid system and a pull-down assay. The negative impact of canine SGTA on androgen receptor (AR) signalling was demonstrated using a reporter assay in androgen-independent human prostate cancer cell lines. Pathological analysis showed overexpression of SGTA in canine prostate cancer, but not in hyperplasia. A reporter assay in prostate cells demonstrated suppression of AR signalling by canine SGTA. Altogether, these results suggest that canine SGTA may play an important role in the acquisition of androgen independence by canine prostate cancer cells. PMID:26346258

  6. Cell-specific distributions of estrogen receptor alpha (ERα) and androgen receptor (AR) in anterior pituitary glands from adult cockerels as revealed by immunohistochemistry.

    PubMed

    Sun, Dehao; Cui, Tongtong; Luo, Haoshu; Li, Ruiguo; Cui, Sheng; Liu, Jiali

    2012-06-01

    Estrogens and androgens play important roles in regulating the hormone-secreting functions of the pituitary gland by binding to their corresponding receptors. However, the expression of estrogen receptors (ERs) and the androgen receptor (AR) and the cell types containing ERs and AR in the anterior pituitary gland of adult chickens have not been well-studied. In this study, the distribution of ERα, AR and their corresponding cell types in the anterior pituitary gland of adult cockerels was detected by immunohistochemistry. The results showed that ERα was expressed in 68.63 % of luteinizing hormone (LH) producing cells but was not found in thyrotropes, lactotropes, somatotropes, corticotropes and folliculo-stellate (FS) cells. Pituitary hormone and AR double labeling results showed that about 37 % of LH cells and 50 % of thyroid-stimulating hormone (TSH) producing cells expressed AR, respectively. In contrast, less than 1 % of the somatotropes had an AR positive signal and AR signals were not detected in lactotropes, corticotropes or FS cells. In addition, there were only a few AR and ERα dual-labeled cells observed. These novel results provide evidence for a cell-specific distribution of ERα and AR in the anterior pituitary from adult cockerels by immunohistochemistry. The different distributions of ERα and AR in the LH cells suggest that the feedback-regulating mechanisms of estrogen and androgen on the pituitary hormones secretion are different. The functions and related mechanisms still need to be elucidated further. PMID:22453555

  7. Seasonal changes of androgen receptor, estrogen receptors and aromatase expression in the medial preoptic area of the wild male ground squirrels (Citellus dauricus Brandt).

    PubMed

    Zhang, F; Wang, J; Jiao, Y; Zhang, L; Zhang, H; Sheng, X; Han, Y; Yuan, Z; Weng, Q

    2016-01-01

    The wild ground squirrel is a typical seasonal breeder. In this study, using RT-PCR, western blot and immunohistochemistry, we investigated the mRNA and protein expressions of androgen receptor (AR), estrogen receptors α and β (ERα and ERβ) and aromatase cytochrome P450 (P450arom) in the medial preoptic area (MPOA) of hypothalamus of the wild male ground squirrel during the breeding season (April), the non-breeding season (June) and pre-hibernation (September). AR, ERα, ERβ and P450arom protein/mRNA were present in the MPOA of all seasons detected. The immunostaining of AR and ERα showed no significant changes in different periods, whereas ERβ and P450arom had higher immunoreactivities during the breeding season and pre-hibernation when compared to those of the non-breeding season. Consistently, both the protein and mRNA levels of P450arom and ERβ were higher in the MPOA of pre-hibernation and the breeding season than in the non-breeding season, whereas no significant difference amongst the three periods was observed for AR and ERα levels. These findings suggested that the MPOA of hypothalamus may be a direct target of androgen and estrogen. Androgen may play important regulatory roles through its receptor and/or the aromatized estrogen in the MPOA of hypothalamus of the wild male ground squirrels. PMID:27349316

  8. Seasonal Changes of Androgen Receptor, Estrogen Receptors and Aromatase Expression in the Medial Preoptic Area of the Wild Male Ground Squirrels (Citellus Dauricus Brandt)

    PubMed Central

    Zhang, F.; Wang, J.; Jiao, Y.; Zhang, L.; Zhang, H.; Sheng, X.; Han, Y.; Yuan, Z.; Weng, Q.

    2016-01-01

    The wild ground squirrel is a typical seasonal breeder. In this study, using RT-PCR, western blot and immunohistochemistry, we investigated the mRNA and protein expressions of androgen receptor (AR), estrogen receptors a and β (ERα and ERβ) and aromatase cytochrome P450 (P450arom) in the medial preoptic area (MPOA) of hypothalamus of the wild male ground squirrel during the breeding season (April), the non-breeding season (June) and pre-hibernation (September). AR, ERα, ERβ and P450arom protein/mRNA were present in the MPOA of all seasons detected. The immunostaining of AR and ERα showed no significant changes in different periods, whereas ERβ and P450arom had higher immunoreactivities during the breeding season and pre-hibernation when compared to those of the non-breeding season. Consistently, both the protein and mRNA levels of P450arom and ERβ were higher in the MPOA of pre-hibernation and the breeding season than in the non-breeding season, whereas no significant difference amongst the three periods was observed for AR and ERα levels. These findings suggested that the MPOA of hypothalamus may be a direct target of androgen and estrogen. Androgen may play important regulatory roles through its receptor and/or the aromatized estrogen in the MPOA of hypothalamus of the wild male ground squirrels. PMID:27349316

  9. Detection of persistent organic pollutants binding modes with androgen receptor ligand binding domain by docking and molecular dynamics

    PubMed Central

    2013-01-01

    Background Persistent organic pollutants (POPs) are persistent in the environment after release from industrial compounds, combustion productions or pesticides. The exposure of POPs has been related to various reproductive disturbances, such as reduced semen quality, testicular cancer, and imbalanced sex ratio. Among POPs, dichlorodiphenyldichloroethylene (4,4’-DDE) and polychlorinated biphenyls (PCBs) are the most widespread and well-studied compounds. Recent studies have revealed that 4,4’-DDE is an antagonist of androgen receptor (AR). However, the mechanism of the inhibition remains elusive. CB-153 is the most common congener of PCBs, while the action of CB-153 on AR is still under debate. Results Molecular docking and molecular dynamics (MD) approaches have been employed to study binding modes and inhibition mechanism of 4,4’-DDE and CB-153 against AR ligand binding domain (LBD). Several potential binding sites have been detected and analyzed. One possible binding site is the same binding site of AR natural ligand androgen 5α-dihydrotestosterone (DHT). Another one is on the ligand-dependent transcriptional activation function (AF2) region, which is crucial for the co-activators recruitment. Besides, a novel possible binding site was observed for POPs with low binding free energy with the receptor. Detailed interactions between ligands and the receptor have been represented. The disrupting mechanism of POPs against AR has also been discussed. Conclusions POPs disrupt the function of AR through binding to three possible biding sites on AR/LBD. One of them shares the same binding site of natural ligand of AR. Another one is on AF2 region. The third one is in a cleft near N-terminal of the receptor. Significantly, values of binding free energy of POPs with AR/LBD are comparable to that of natural ligand androgen DHT. PMID:24053684

  10. Widely used pharmaceuticals present in the environment revealed as in vitro antagonists for human estrogen and androgen receptors.

    PubMed

    Ezechiáš, Martin; Janochová, Jana; Filipová, Alena; Křesinová, Zdena; Cajthaml, Tomáš

    2016-06-01

    A considerable amount of scientific evidence indicates that a number of pharmaceuticals that could be detected in the environment can contribute towards the development of problems associated with human reproductive systems, as well as those of wildlife. We investigated the estrogenic and androgenic effects of select pharmaceuticals with high production volume and environmental relevance. We examined the receptor-binding activities of these pharmaceuticals in the T47D human cell line using altered secretion of cytokine CXCL12. Functional yeast-luciferase reporter gene assays were also employed to confirm the mechanism of receptor binding by estrogen and androgen. Non-steroidal anti-inflammatory drugs, namely ibuprofen, diclofenac and antiarrhythmic agent amiodarone showed strong anti-estrogenic effects in the T47D cell line. In the yeast-luciferase assay, these anti-inflammatory drugs also demonstrated anti-estrogenic potency and inhibited the E2 response in a concentration-dependent manner. Amiodarone did not exhibit any response in the yeast-luciferase assay; therefore, the endocrine disruption presumably occurred at a different level without directly involving the receptor. All the anti-inflammatory drugs considered in this study, including ketoprofen, naproxen and clofibrate, exhibited a dose-dependent antagonism towards the androgen receptor in the yeast-luciferase assays. Several other drugs, including the stimulant caffeine, did not show any response in the tests that were employed. A risk assessment analysis using 'Hazard Quotient' suggested a potential risk, especially in the cases of ibuprofen, ketoprofen, diclofenac and clofibrate. The results reveal the intrinsic endocrine disrupting nature of several pharmaceuticals and thus could contribute towards explaining a number of adverse health effects on humans and wildlife. PMID:26978704

  11. A NOVEL CELL LINE, MDA-KB2, THAT STABLY EXPRESSES AN ANDROGEN AND GLUCOCORTICOID RESPONSIVE REPORTER FOR THE DETECTION OF HORMONE RECEPTOR AGONISTS AND ANTAGONISTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency has proposed that in vitro assays for estrogen receptor (ER) and androgen receptor (AR) mediated actions be included in a Tier I screening battery to detect hormonally active chemicals. Herein we describe the development of a novel stab...

  12. Polyester monomers lack ability to bind and activate both androgenic and estrogenic receptors as determined by In Vitro and In Silico methods

    PubMed Central

    Osimitz, Thomas G.; Welsh, William J.; Ai, Ni; Toole, Colleen

    2015-01-01

    The paper presents results from the screening of seven monomers used by Eastman Chemical to make various polymers. Ethylene glycol, diethylene glycol, polytetramethylene glycol, isophthalic acid, monosodium-5-sulfoisophthalic acid, 1,4-cyclohexanedicarboxylic acid, and dimethylcyclohexanedicarboxylate were screened for potential androgenicity or estrogenicity. The following studies were conducted: QSAR for binding to the AR and ER, in vitro Androgen Receptor Binding Assay, in vitro Estrogen Receptor Binding Assays (alpha and beta isoforms), in vitro Androgen Receptor Transactivation Assay in human cells, and in vitro Estrogen Receptor Transactivation Assay in human cells. None of the QSAR models predicted that any of the monomers possessed appreciable binding affinity for either AR or ER. Binding assays showed no evidence of interaction with either the AR or the alpha or beta ER receptors. Similarly, the AR and ER transactivation assays were negative. Moreover, six of the seven monomers have been subjected to 13-week and developmental toxicity studies in rats with no androgen- or estrogen-related effects being noted. Given the negative results of the in vitro screening assays (except PMG which demonstrated cytotoxicity) as well as available repeated dose and developmental and reproductive studies, the data suggest that none of the monomers tested exhibit androgenic or estrogenic hazards. PMID:25455886

  13. The Cochaperone SGTA (Small Glutamine-rich Tetratricopeptide Repeat-containing Protein Alpha) Demonstrates Regulatory Specificity for the Androgen, Glucocorticoid, and Progesterone Receptors*

    PubMed Central

    Paul, Atanu; Garcia, Yenni A.; Zierer, Bettina; Patwardhan, Chaitanya; Gutierrez, Omar; Hildenbrand, Zacariah; Harris, Diondra C.; Balsiger, Heather A.; Sivils, Jeffrey C.; Johnson, Jill L.; Buchner, Johannes; Chadli, Ahmed; Cox, Marc B.

    2014-01-01

    Steroid hormone receptors are ligand-dependent transcription factors that require the ordered assembly of multichaperone complexes for transcriptional activity. Although heat shock protein (Hsp) 90 and Hsp70 are key players in this process, multiple Hsp70- and Hsp90-associated cochaperones associate with receptor-chaperone complexes to regulate receptor folding and activation. Small glutamine-rich tetratricopeptide repeat-containing protein alpha (SGTA) was recently characterized as an Hsp70 and Hsp90-associated cochaperone that specifically regulates androgen receptor activity. However, the specificity of SGTA for additional members of the steroid hormone receptor superfamily and the mechanism by which SGTA regulates receptor activity remain unclear. Here we report that SGTA associates with and specifically regulates the androgen, glucocorticoid, and progesterone receptors and has no effect on the mineralocorticoid and estrogen receptors in both yeast and mammalian cell-based reporter assays. In both systems, SGTA knockdown/deletion enhances receptor activity, whereas SGTA overexpression suppresses receptor activity. We demonstrate that SGTA binds directly to Hsp70 and Hsp90 in vitro with similar affinities yet predominately precipitates with Hsp70 from cell lysates, suggesting a role for SGTA in early, Hsp70-mediated folding. Furthermore, SGTA expression completely abrogates the regulation of receptor function by FKBP52 (52-kDa FK506-binding protein), which acts at a later stage of the chaperone cycle. Taken together, our data suggest a role for SGTA at distinct steps in the chaperone-dependent modulation of androgen, glucocorticoid, and progesterone receptor activity. PMID:24753260

  14. Antiinflammatory effect of androgen receptor activation in human benign prostatic hyperplasia cells.

    PubMed

    Vignozzi, Linda; Cellai, Ilaria; Santi, Raffaella; Lombardelli, Letizia; Morelli, Annamaria; Comeglio, Paolo; Filippi, Sandra; Logiodice, Federica; Carini, Marco; Nesi, Gabriella; Gacci, Mauro; Piccinni, Marie-Pierre; Adorini, Luciano; Maggi, Mario

    2012-07-01

    Progression of benign prostatic hyperplasia (BPH) involves chronic inflammation and immune dysregulation. Preclinical studies have demonstrated that prostate inflammation and tissue remodeling are exacerbated by hypogonadism and prevented by testosterone supplementation. We now investigated whether, in humans, hypogonadism was associated with more severe BPH inflammation and the in vitro effect of the selective androgen receptor agonist dihydrotestosterone (DHT) on cultures of stromal cells derived from BPH patients (hBPH). Histological analysis of inflammatory infiltrates in prostatectomy specimens from a cohort of BPH patients and correlation with serum testosterone level was performed. Even after adjusting for confounding factors, hypogonadism was associated with a fivefold increased risk of intraprostatic inflammation, which was also more severe than that observed in eugonadal BPH patients. Triggering hBPH cells by inflammatory stimuli (tumor necrosis factor α, lipopolysaccharide, or CD4(+)T cells) induced abundant secretion of inflammatory/growth factors (interleukin 6 (IL6), IL8, and basic fibroblast growth factor (bFGF)). Co-culture of CD4(+)T cells with hBPH cells induced secretion of Th1 inducer (IL12), Th1-recruiting chemokine (interferon γ inducible protein 10, IP10), and Th2 (IL9)- and Th17 (IL17)-specific cytokines. Pretreatment with DHT inhibited NF-κB activation and suppressed secretion of several inflammatory/growth factors, with the most pronounced effects on IL8, IL6, and bFGF. Reduced inflammatory cytokine production by T-cells, an increase in IL10, and a significant reduction of T cells proliferation suggested that DHT exerted a broad anti inflammatory effect on testosterone cells [corrected]. In conclusion, our data demonstrate that DHT exerts an immune regulatory role on human prostatic stromal cells, inhibiting their potential to actively induce and/or sustain autoimmune and inflammatory responses. PMID:22562653

  15. Ericifolin: a novel antitumor compound from allspice that silences androgen receptor in prostate cancer

    PubMed Central

    Lokeshwar, Bal L.

    2013-01-01

    Silencing of androgen receptor (AR) signaling is a specific and effective mechanism to cure cancer of the prostate (CaP). In this study, the isolation and characterization of a compound from the aromatic berries of Pimenta dioica (allspice) that silences AR is presented. Potential antitumor activities of an aqueous allspice extract (AAE) and a compound purified from the extract were tested on CaP cells. AAE inhibited tumor cell proliferation and colony formation (50% growth inhibition ∼40–85 µg/ml) but not the viability of quiescent normal fibroblasts or non-tumorigenic prostate cells. In tumor cells, AAE inhibited cell cycle progression at G1/S, induced apoptosis or autophagy. Apoptosis was by caspase-dependent poly (ADP ribose) polymerase cleavage. A caspase-independent, apoptosis-inducing factor-mediated mechanism of apoptosis caused cell death in castration-resistant AR-positive or AR-negative CaP cells, such as CWR22RV1, PC-3 or DU145 cells. Treatment with AAE decreased the levels of AR messenger RNA (mRNA), protein and silenced AR activity in AR-positive cells. AR depletion was due to inhibition of AR promoter activity and mRNA stability. Delayed tumor growth (~55%) without measurable systemic toxicity was observed in LNCaP tumor-bearing mice treated with AAE by oral or intraperitoneal routes. LNCaP tumor tissues from AAE-treated mice revealed increased apoptosis as a potential mechanism of antitumor activity of AAE. The chemical identity of bioactive compound in AAE was established through multistep high-performance liquid chromatography fractionation, mass and Nuclear Magnetic Resonance spectroscopies. The compound, eugenol 5-O-β-(6′-galloylglucopyranoside) or ericifolin (EF), showed antiproliferative, pro-apoptosis and anti-AR transcription activities. These results demonstrate a potential use of AAE and EF against prostate cancer. PMID:23568956

  16. Positive association of the androgen receptor CAG repeat length polymorphism with the risk of prostate cancer.

    PubMed

    Paz-Y-Miño, César; Robles, Paulo; Salazar, Carolina; Leone, Paola E; García-Cárdenas, Jennyfer M; Naranjo, Manuel; López-Cortés, Andrés

    2016-08-01

    Prostate cancer (PC) is the most frequently diagnosed cancer in Ecuador (15.6%). The androgen receptor gene codes for a protein that has an androgen‑binding domain, DNA‑binding domain and N‑terminal domain, which contains two polymorphic trinucleotide repeats (CAG and GGC). The aim of the present study was to determine whether variations in the number of repetitions of CAG and GGC are associated with the pathological features and the risk of developing PC. The polymorphic CAG and GGC repeat lengths in 108 mestizo patients with PC, 148 healthy mestizo individuals, and 78 healthy indigenous individuals were examined via a retrospective case‑control study. Genotypes were determined by genomic sequencing. The results demonstrated that patients with ≤21 CAG repeats have an increased risk of developing PC [odds ratio (OR)=2.99, 95% confidence interval (CI) =1.79‑5.01; P<0.001]. The presence of ≤21 CAG repeats was also associated with a tumor stage ≥T2c (OR=4.75; 95% CI=1.77‑12.72; P<0.005) and a Gleason score ≥7 (OR=2.9; 95% CI=1.1‑7.66; P=0.03). In addition, the combination of ≤21 CAG and ≥17 GGC repeats was associated with the risk of developing PC (OR=2.42; 95% CI=1.38‑4.25; P=0.002) and with tumor stage ≥T2c (OR=2.77; 95% CI=1.13‑6.79; P=0.02). In conclusion, the histopathological characteristics and PC risk in Ecuadorian indigenous and mestizo populations differs in association with the CAG repeats, and the combination of CAG and GGC repeats. PMID:27357524

  17. A preliminary MTD-PLS study for androgen receptor binding of steroid compounds

    NASA Astrophysics Data System (ADS)

    Bora, Alina; Seclaman, E.; Kurunczi, L.; Funar-Timofei, Simona

    The relative binding affinities (RBA) of a series of 30 steroids for Human Androgen Receptor (AR) were used to initiate a MTD-PLS study. The 3D structures of all the compounds were obtained through geometry optimization in the framework of AM1 semiempirical quantum chemical method. The MTD hypermolecule (HM) was constructed, superposing these structures on the AR-bonded dihydrotestosterone (DHT) skeleton obtained from PDB (AR complex, ID 1I37). The parameters characterizing the HM vertices were collected using: AM1 charges, XlogP fragmental values, calculated fragmental polarizabilities (from refractivities), volumes, and H-bond parameters (Raevsky's thermodynamic originated scale). The resulted QSAR data matrix was submitted to PCA (Principal Component Analysis) and PLS (Projections in Latent Structures) procedure (SIMCA P 9.0); five compounds were selected as test set, and the remaining 25 molecules were used as training set. In the PLS procedure supplementary chemical information was introduced, i.e. the steric effect was always considered detrimental, and the hydrophobic and van der Waals interactions were imposed to be beneficial. The initial PLS model using the entire training set has the following characteristics: R2Y = 0.584, Q2 = 0.344. Based on distances to the model criterions (DMODX and DMODY), five compounds were eliminated and the obtained final model had the following characteristics: R2Y D 0.891, Q2 D 0.591. For this the external predictivity on the test set was unsatisfactory. A tentative explanation for these behaviors is the weak information content of the input QSAR matrix for the present series comparatively with other successful MTD-PLS modeling published elsewhere.

  18. Elevated expression of the Sertoli cell androgen receptor disrupts male fertility.

    PubMed

    Hazra, Rasmani; Upton, Dannielle; Desai, Reena; Noori, Omar; Jimenez, Mark; Handelsman, David J; Allan, Charles M

    2016-08-01

    Recently, we created a unique gain-of-function mouse model with Sertoli cell-specific transgenic androgen receptor expression (TgSCAR) showing that SCAR activity controls the synchronized postnatal development of somatic Sertoli and Leydig cells and meiotic-postmeiotic germ cells. Moderate TgSCAR (TgSCAR(m)) expression reduced testis size but had no effect on male fertility. Here, we reveal that higher TgSCAR expression (TgSCAR(H)) causes male infertility. Higher SCAR activity, shown by upregulated AR-dependent transcripts (Rhox5, Spinw1), resulted in smaller adult TgSCAR(H) testes (50% of normal) despite normal or elevated circulating and intratesticular testosterone levels. Unlike fertile TgSCAR(m) males, testes of adult TgSCAR(H) males exhibited focal regions of interstitial hypertrophy featuring immature adult Leydig cells and higher intratesticular dihydrotestosterone and 5α-androstane 3α,17β-diol levels that are normally associated with pubertal development. Mature TgSCAR(H) testes also exhibited markedly reduced Sertoli cell numbers (70%), although meiotic and postmeiotic germ cell/Sertoli cell ratios were twofold higher than normal, suggesting that elevated TgSCAR activity supports excessive spermatogenic development. Concurrent with the higher germ cell load of TgSCAR(H) Sertoli cells were increased levels of apoptotic germ cells in TgSCAR(H) relative to TgSCAR(m) testes. In addition, TgSCAR(H) testes displayed unique morphological degeneration that featured accumulated cellular and spermatozoa clusters in dilated channels of rete testes, consistent with reduced epididymal sperm numbers. Our findings reveal for the first time that excessive Sertoli cell AR activity in mature testes can reach a level that disturbs Sertoli/germ cell homeostasis, impacts focal Leydig cell function, reduces sperm output, and disrupts male fertility. PMID:27354237

  19. Assessment of a recombinant androgen receptor binding assay: initial steps towards validation.

    PubMed

    Freyberger, Alexius; Weimer, Marc; Tran, Hoai-Son; Ahr, Hans-Jürgen

    2010-08-01

    Despite more than a decade of research in the field of endocrine active compounds with affinity for the androgen receptor (AR), still no validated recombinant AR binding assay is available, although recombinant AR can be obtained from several sources. With funding from the European Union (EU)-sponsored 6th framework project, ReProTect, we developed a model protocol for such an assay based on a simple AR binding assay recently developed at our institution. Important features of the protocol were the use of a rat recombinant fusion protein to thioredoxin containing both the hinge region and ligand binding domain (LBD) of the rat AR (which is identical to the human AR-LBD) and performance in a 96-well plate format. Besides two reference compounds [dihydrotestosterone (DHT), androstenedione] ten test compounds with different affinities for the AR [levonorgestrel, progesterone, prochloraz, 17alpha-methyltestosterone, flutamide, norethynodrel, o,p'-DDT, dibutylphthalate, vinclozolin, linuron] were used to explore the performance of the assay. At least three independent experiments per compound were performed. The AR binding properties of reference and test compounds were well detected, in terms of the relative ranking of binding affinities, there was good agreement with published data obtained from experiments using recombinant AR preparations. Irrespective of the chemical nature of the compound, individual IC(50)-values for a given compound varied by not more than a factor of 2.6. Our data demonstrate that the assay reliably ranked compounds with strong, weak, and no/marginal affinity for the AR with high accuracy. It avoids the manipulation and use of animals, as a recombinant protein is used and thus contributes to the 3R concept. On the whole, this assay is a promising candidate for further validation. PMID:19833195

  20. Estrogen and androgen receptor expression in surface epithelium and inclusion cyst in the ovary of premenopausal and postmenopausal women

    PubMed Central

    2013-01-01

    Background The importance of surface epithelium and epithelial inclusion cysts in the ovary arises from studies demonstrating that these structures are susceptible to epithelial ovarian cancer development. The expression of estrogen receptor alpha (ER alpha), androgen receptor (AR), in epithelial cells of the ovary from premenopausal and postmenopausal women is interesting because sexual steroid hormones are involved in cell growth and differentiation. Methods The presence of ER alpha, AR, and the orphan G protein-coupled receptor 30 (GPR30) was demonstrated by immunofluorescence in ovaries obtained from 79 pre and postmenopausal patients, undergoing histero-salpingo-oophorectomy for proliferative gynecological diseases. The proportion of patients that displayed positive reaction for estrogen and androgen receptors in epithelial cells of the ovary was evaluated according to menopausal status and associated pathology. Results The proportion of patients that displayed a positive receptor expression in the epithelial cells of the ovarian surface and cortical inclusion cysts shows that ER alpha is present in 20 of 79 patients (0.25), AR in 33 of 79 (0.42) and GPR30 in 38 of 55 (0.69). There are no differences in ER alpha, AR, and GPR30 expression between pre and postmenopausal patients and considering the associated pathology, proportions for ER alpha and GPR30 are similar. The patients with cervical cancer show a higher proportion of AR expression in epithelial cells of the ovary, which is statistically significant (P < 0.01) compared with patients with other proliferative diseases. Conclusions The presence of ER alpha, AR, and GPR30 in the surface epithelial ovarian cells and its derivatives are observed with a proportion that is specific for each receptor. The proportion of expression for these receptors in the epithelial cells of the ovary does not change after menopause. The proportion of ovaries with AR positive epithelial cells in patients with cervical

  1. Duplicated Leptin Receptors in Two Species of Eel Bring New Insights into the Evolution of the Leptin System in Vertebrates

    PubMed Central

    Morini, Marina; Pasquier, Jérémy; Dirks, Ron; van den Thillart, Guido; Tomkiewicz, Jonna; Rousseau, Karine; Dufour, Sylvie; Lafont, Anne-Gaëlle

    2015-01-01

    Since its discovery in mammals as a key-hormone in reproduction and metabolism, leptin has been identified in an increasing number of tetrapods and teleosts. Tetrapods possess only one leptin gene, while most teleosts possess two leptin genes, as a result of the teleost third whole genome duplication event (3R). Leptin acts through a specific receptor (LEPR). In the European and Japanese eels, we identified two leptin genes, and for the first time in vertebrates, two LEPR genes. Synteny analyses indicated that eel LEPRa and LEPRb result from teleost 3R. LEPRb seems to have been lost in the teleost lineage shortly after the elopomorph divergence. Quantitative PCRs revealed a wide distribution of leptins and LEPRs in the European eel, including tissues involved in metabolism and reproduction. Noticeably, leptin1 was expressed in fat tissue, while leptin2 in the liver, reflecting subfunctionalization. Four-month fasting had no impact on the expression of leptins and LEPRs in control European eels. This might be related to the remarkable adaptation of silver eel metabolism to long-term fasting throughout the reproductive oceanic migration. In contrast, sexual maturation induced differential increases in the expression of leptins and LEPRs in the BPG-liver axis. Leptin2 was strikingly upregulated in the liver, the central organ of the reproductive metabolic challenge in teleosts. LEPRs were differentially regulated during sexual maturation, which may have contributed to the conservation of the duplicated LEPRs in this species. This suggests an ancient and positive role of the leptin system in the vertebrate reproductive function. This study brings new insights on the evolutionary history of the leptin system in vertebrates. Among extant vertebrates, the eel represents a unique case of duplicated leptins and leptin receptors as a result of 3R. PMID:25946034

  2. Duplicated leptin receptors in two species of eel bring new insights into the evolution of the leptin system in vertebrates.

    PubMed

    Morini, Marina; Pasquier, Jérémy; Dirks, Ron; van den Thillart, Guido; Tomkiewicz, Jonna; Rousseau, Karine; Dufour, Sylvie; Lafont, Anne-Gaëlle

    2015-01-01

    Since its discovery in mammals as a key-hormone in reproduction and metabolism, leptin has been identified in an increasing number of tetrapods and teleosts. Tetrapods possess only one leptin gene, while most teleosts possess two leptin genes, as a result of the teleost third whole genome duplication event (3R). Leptin acts through a specific receptor (LEPR). In the European and Japanese eels, we identified two leptin genes, and for the first time in vertebrates, two LEPR genes. Synteny analyses indicated that eel LEPRa and LEPRb result from teleost 3R. LEPRb seems to have been lost in the teleost lineage shortly after the elopomorph divergence. Quantitative PCRs revealed a wide distribution of leptins and LEPRs in the European eel, including tissues involved in metabolism and reproduction. Noticeably, leptin1 was expressed in fat tissue, while leptin2 in the liver, reflecting subfunctionalization. Four-month fasting had no impact on the expression of leptins and LEPRs in control European eels. This might be related to the remarkable adaptation of silver eel metabolism to long-term fasting throughout the reproductive oceanic migration. In contrast, sexual maturation induced differential increases in the expression of leptins and LEPRs in the BPG-liver axis. Leptin2 was strikingly upregulated in the liver, the central organ of the reproductive metabolic challenge in teleosts. LEPRs were differentially regulated during sexual maturation, which may have contributed to the conservation of the duplicated LEPRs in this species. This suggests an ancient and positive role of the leptin system in the vertebrate reproductive function. This study brings new insights on the evolutionary history of the leptin system in vertebrates. Among extant vertebrates, the eel represents a unique case of duplicated leptins and leptin receptors as a result of 3R. PMID:25946034

  3. The NLR-related protein NWD1 is associated with prostate cancer and modulates androgen receptor signaling

    PubMed Central

    Correa, Ricardo G.; Krajewska, Maryla; Ware, Carl F.; Gerlic, Motti; Reed, John C.

    2014-01-01

    Prostate cancer (PCa) is among the leading causes of cancer-related death in men. Androgen receptor (AR) signaling plays a seminal role in prostate development and homeostasis, and dysregulation of this pathway is intimately linked to prostate cancer pathogenesis and progression. Here, we identify the cytosolic NLR-related protein NWD1 as a novel modulator of AR signaling. We determined that expression of NWD1 becomes elevated during prostate cancer progression, based on analysis of primary tumor specimens. Experiments with cultured cells showed that NWD1 expression is up-regulated by the sex-determining region Y (SRY) family proteins. Gene silencing procedures, in conjunction with transcriptional profiling, showed that NWD1 is required for expression of PDEF (prostate-derived Ets factor), which is known to bind and co-regulate AR. Of note, NWD1 modulates AR protein levels. Depleting NWD1 in PCa cell lines reduces AR levels and suppresses activity of androgen-driven reporter genes. NWD1 knockdown potently suppressed growth of androgen-dependent LNCaP prostate cancer cells, thus showing its functional importance in an AR-dependent tumor cell model. Proteomic analysis suggested that NWD1 associates with various molecular chaperones commonly related to AR complexes. Altogether, these data suggest a role for tumor-associated over-expression of NWD1 in dysregulation of AR signaling in PCa. PMID:24681825

  4. Induction of Prostatic Intraepithelial Neoplasia and Modulation of Androgen Receptor by ETS Variant 1/ETS-Related Protein 81

    PubMed Central

    Shin, Sook; Kim, Tae-Dong; Jin, Fang; van Deursen, Jan M.; Dehm, Scott M.; Tindall, Donald J.; Grande, Joseph P.; Munz, Jan-Marie; Vasmatzis, George; Janknecht, Ralf

    2014-01-01

    ETS variant 1 (ETV1), also known as ETS-related protein 81, is overexpressed in prostate tumors, but whether and how this transcription factor affects tumorigenesis has remained elusive. Here, we show that ETV1 is primarily overexpressed in the most aggressive human prostate tumors. Transgenic ETV1 mice developed prostatic intraepithelial neoplasia as well as hyperplasia/neoplasia in seminal vesicles. Moreover, ETV1 cooperated with the androgen receptor (AR) to bind to the prostate-specific antigen enhancer and stimulate gene transcription. Consistent with its ability to physically interact with AR, ETV1 rendered an ETV1 binding site–driven reporter androgen inducible, and, on the other hand, ETV1 superinduced transcription from an AR binding site on androgen stimulation. In conclusion, our study substantiates that ETV1 overexpression is an underlying cause in the development of prostate and possibly also seminal vesicle cancer. Its interaction with and activation of AR provides a molecular mechanism on how ETV1 exerts its deleterious function. Thus, inhibiting ETV1 or blocking its interaction with AR may represent novel strategies in prostate cancer therapy. PMID:19789348

  5. Local delivery of a selective androgen receptor modulator failed as an anabolic agent in a rat bone marrow ablation model

    PubMed Central

    Aro, Hannu T; Kulkova, Julia; Moritz, Niko; Kähkönen, Esa; Mattila, Riina H

    2015-01-01

    Background and purpose — Selective androgen receptor modulators (SARMs) have been developed to have systemic anabolic effects on bones and muscles without the adverse effects of steroidal androgens. One unexplored therapeutic option is the targeted application of SARMs for the enhancement of local new bone formation. We evaluated the osteogenic efficacy of a locally released SARM (ORM-11984). Methods — ORM-11984 was mixed with a copolymer of L-lactide and ɛ-caprolactone (PLCL). An in vitro dissolution test confirmed the sustainable release of ORM-11984 from the matrix. A bone marrow ablation model was used in female Sprague-Dawley rats. Implants containing 10%, 30%, or 50% ORM-11984 by weight or pure PLCL were inserted into the medullary canal of the ablated tibia. At 6 and 12 weeks, the volume of intramedullary new bone and the perimeter of bone-implant contact were measured by micro-computed tomography and histomorphometry. Results — Contrary to our hypothesis, there was a negative correlation between the amount of new bone around the implant and the dose of ORM-11984. There was only a mild (and not statistically significant) enhancement of bone formation in ablated bones subjected to the lowest dose of the SARM (10%). Interpretation — This study suggests that intramedullary/endosteal osteogenesis had a negative, dose-dependent response to locally released SARM. This result highlights the complexity of androgenic effects on bones and also suggests that there are biological limits to the targeted local application of SARMs. PMID:26198725

  6. Hepatocyte nuclear factor-3 alpha (HNF-3{alpha}) negatively regulates androgen receptor transactivation in prostate cancer cells

    SciTech Connect

    Lee, Hyun Joo; Hwang, Miok; Chattopadhyay, Soma; Choi, Hueng-Sik; Lee, Keesook

    2008-03-07

    The androgen receptor (AR) is involved in the development and progression of prostate cancers. However, the mechanisms by which this occurs remain incompletely understood. In previous reports, hepatocyte nuclear factor-3{alpha} (HNF-3{alpha}) has been shown to be expressed in the epithelia of the prostate gland, and has been determined to regulate the transcription of prostate-specific genes. In this study, we report that HNF-3{alpha} functions as a novel corepressor of AR in prostatic cells. HNF-3{alpha} represses AR transactivation on target promoters containing the androgen response element (ARE) in a dose-dependent manner. HNF-3{alpha} interacts physically with AR, and negatively regulates AR transactivation via competition with AR coactivators, including GRIP1. Furthermore, HNF-3{alpha} overexpression reduces the androgen-induced expression of prostate-specific antigen (PSA) in LNCaP cells. Taken together, our findings indicate that HNF-3{alpha} is a novel corepressor of AR, and predict its effects on the proliferation of prostate cancer cells.

  7. Identification of NR0B1 as a novel androgen receptor co-repressor in mouse Sertoli cells.

    PubMed

    Li, Yu-Chi; Luo, Man-Ling; Guo, Huan; Wang, Tian-Tian; Lin, Shou-Ren; Chen, Jian-Bo; Ma, Qian; Gu, Yan-Li; Jiang, Zhi-Mao; Gui, Yao-Ting

    2016-09-01

    Nuclear receptor subfamily 0 group B member 1 (Nr0b1) is an atypical member of the nuclear receptor family that is predominantly expressed in mouse Sertoli cells (SCs). Mutations of NR0B1 in humans cause adrenal failure and hypogonadotropic hypogonadism. The targeted mutagenesis of Nr0b1 in mice has revealed a primary gonadal defect characterized by the overexpression of aromatase and cellular obstruction of the seminiferous tubules and efferent ductules, leading to germ cell death and infertility. The transgenic expression of Nr0b1 under the control of the Müllerian-inhibiting substance promoter (MIS-Nr0b1), which is selectively expressed in SCs, improves fertility. Testicular androgen receptor (AR) was also expressed in SCs. Many genes are directly regulated by androgen and its AR, which are involved in spermatogenesis and male infertility. As the association between NR0B1 and AR remains unclear in mouse SCs, we decided to further explore the relationship between them. In the present study, we have identified NR0B1 as a novel AR co-repressor in mouse SCs. Using RT‑qPCR and immunofluorescence, we determined that NR0B1 was mainly expressed in mouse SCs in an age-dependent manner from 2-8 weeks of age postnatally. The inhibition of the effects of AR on AR target genes by NR0B1, in an androgen‑dependent manner, was further demonstrated by western blot analysis and RT-qPCR in TM4 cells, a mouse Sertoli cell line. Finally, in vitro luciferase and co-immunoprecipitation assays validated that NR0B1, as an AR co-repressor, significantly inhibited the transcriptional activation of its target genes. These results suggest that novel inhibitory mechanisms underlie the effects of NR0B1 in modulating androgen-dependent gene transcription in mouse SCs. PMID:27431683

  8. Estrogen and androgen receptor activities of hydraulic fracturing chemicals and surface and ground water in a drilling-dense region.

    PubMed

    Kassotis, Christopher D; Tillitt, Donald E; Davis, J Wade; Hormann, Annette M; Nagel, Susan C

    2014-03-01

    The rapid rise in natural gas extraction using hydraulic fracturing increases the potential for contamination of surface and ground water from chemicals used throughout the process. Hundreds of products containing more than 750 chemicals and components are potentially used throughout the extraction process, including more than 100 known or suspected endocrine-disrupting chemicals. We hypothesized that a selected subset of chemicals used in natural gas drilling operations and also surface and ground water samples collected in a drilling-dense region of Garfield County, Colorado, would exhibit estrogen and androgen receptor activities. Water samples were collected, solid-phase extracted, and measured for estrogen and androgen receptor activities using reporter gene assays in human cell lines. Of the 39 unique water samples, 89%, 41%, 12%, and 46% exhibited estrogenic, antiestrogenic, androgenic, and antiandrogenic activities, respectively. Testing of a subset of natural gas drilling chemicals revealed novel antiestrogenic, novel antiandrogenic, and limited estrogenic activities. The Colorado River, the drainage basin for this region, exhibited moderate levels of estrogenic, antiestrogenic, and antiandrogenic activities, suggesting that higher localized activity at sites with known natural gas-related spills surrounding the river might be contributing to the multiple receptor activities observed in this water source. The majority of water samples collected from sites in a drilling-dense region of Colorado exhibited more estrogenic, antiestrogenic, or antiandrogenic activities than reference sites with limited nearby drilling operations. Our data suggest that natural gas drilling operations may result in elevated endocrine-disrupting chemical activity in surface and ground water. PMID:24424034

  9. Dose-dependent effects of small-molecule antagonists on the genomic landscape of androgen receptor binding

    PubMed Central

    2012-01-01

    Background The androgen receptor plays a critical role throughout the progression of prostate cancer and is an important drug target for this disease. While chromatin immunoprecipitation coupled with massively parallel sequencing (ChIP-Seq) is becoming an essential tool for studying transcription and chromatin modification factors, it has rarely been employed in the context of drug discovery. Results Here we report changes in the genome-wide AR binding landscape due to dose-dependent inhibition by drug-like small molecules using ChIP-Seq. Integration of sequence analysis, transcriptome profiling, cell viability assays and xenograft tumor growth inhibition studies enabled us to establish a direct cistrome-activity relationship for two novel potent AR antagonists. By selectively occupying the strongest binding sites, AR signaling remains active even when androgen levels are low, as is characteristic of first-line androgen ablation therapy. Coupled cistrome and transcriptome profiling upon small molecule antagonism led to the identification of a core set of AR direct effector genes that are most likely to mediate the activities of targeted agents: unbiased pathway mapping revealed that AR is a key modulator of steroid metabolism by forming a tightly controlled feedback loop with other nuclear receptor family members and this oncogenic effect can be relieved by antagonist treatment. Furthermore, we found that AR also has an extensive role in negative gene regulation, with estrogen (related) receptor likely mediating its function as a transcriptional repressor. Conclusions Our study provides a global and dynamic view of AR’s regulatory program upon antagonism, which may serve as a molecular basis for deciphering and developing AR therapeutics. PMID:22849360

  10. Testosterone regulates androgen receptor immunoreactivity in the copulatory, but not courtship, neuromuscular system in adult male green anoles.

    PubMed

    Holmes, M M; Wade, J

    2005-09-01

    Androgens regulate the expression of male reproductive behaviour in diverse vertebrate species, often acting on androgen receptors (AR) to induce structural or functional changes in the nervous system and periphery. Male green anoles possess two sexually dimorphic neuromuscular systems, one controlling throat fan (dewlap) extension, which occurs during courtship, and the other mediating copulatory organ function. Although androgens are required for behavioural activation in both systems, testosterone has differential effects on the neuromuscular morphology. It increases the size of copulatory muscle fibres during the breeding season, but significant effects on dewlap muscle fibre size and motoneurone soma size in either system have not been detected. Corresponding to the lack of testosterone-induced morphological effects in the courtship system, relatively low levels of AR are expressed in the associated motoneurones. The present experiment had two goals, aiming to determine whether: (i) the other courtship and copulatory neuromuscular tissues express AR and (ii) testosterone and/or seasonal environmental changes regulate AR expression. The percentage of AR+ nuclei was evaluated in both the breeding and nonbreeding seasons in gonadally intact adult males (Experiment 1) and in castrated males treated with either testosterone or vehicle (Experiment 2). AR was extensively expressed in the dewlap and copulatory muscles, and in a high percentage of the copulatory motoneurones, but immunoreactivity did not vary across season. Testosterone increased the percentage of AR+ nuclei in the copulatory muscles of both breeding and nonbreeding males but not in the dewlap muscle or copulatory motoneurones. Finally, the target structures for both systems (cartilages and hemipenes) expressed AR in all animals. Therefore, the effects of testosterone on AR immunoreactivity suggest that up-regulation of the receptors may be important for morphological change. However, because all

  11. A precisely substituted benzopyran targets androgen refractory prostate cancer cells through selective modulation of estrogen receptors

    SciTech Connect

    Kumar, Rajeev; Verma, Vikas; Sharma, Vikas; Jain, Ashish; Singh, Vishal; Sarswat, Amit; Maikhuri, Jagdamba P.; Sharma, Vishnu L.; Gupta, Gopal

    2015-03-15

    Dietary consumption of phytoestrogens like genistein has been linked with lower incidence of prostate cancer. The estradiol-like benzopyran core of genistein confers estrogen receptor-β (ER-β) selectivity that imparts weak anti-proliferative activity against prostate cancer cells. DL-2-[4-(2-piperidinoethoxy)phenyl]-3-phenyl-2H-1-benzopyran (BP), a SERM designed with benzopyran core, targeted androgen independent prostate cancer (PC-3) cells 14-times more potently than genistein, ~ 25% more efficiently than tamoxifen and 6.5-times more actively than ICI-182780, without forfeiting significant specificity in comparison to genistein. BP increased apoptosis (annexin-V and TUNEL labeling), arrested cell cycle, and significantly increased caspase-3 activity along with mRNA expressions of estrogen receptor (ER)-β and FasL (qPCR) in PC-3 cells. In classical ERE-luc reporter assay BP behaved as a potent ER-α antagonist and ER-β agonist. Accordingly, it decreased expression of ER-α target PS2 (P < 0.01) and increased expression of ER-β target TNF-α (P < 0.05) genes in PC-3. ER-β deficient PC-3 (siRNA-transfected) was resistant to apoptotic and anti-proliferative actions of SERMs, including stimulation of FasL expression by BP. BP significantly inhibited phosphorylation of Akt and ERK-1/2, JNK and p38 in PC-3 (immunoblotting), and thus adopted a multi-pathway mechanism to exert a more potent anti-proliferative activity against prostate cancer cells than natural and synthetic SERMs. Its precise ER-subtype specific activity presents a unique lead structure for further optimization. - Highlights: • BP with benzopyran core of genistein was identified for ER-β selective action. • BP was 14-times more potent than genistien in targeting prostate cancer cells. • It behaved as a potent ER-β agonist and ER-α antagonist in gene reporter assays. • BP's anti-proliferative action was inhibited significantly in ER-β deficient cells. • BP — a unique lead structure

  12. An androgen receptor mutation in the MDA-MB-453 cell line model of molecular apocrine breast cancer compromises receptor activity.

    PubMed

    Moore, Nicole L; Buchanan, Grant; Harris, Jonathan M; Selth, Luke A; Bianco-Miotto, Tina; Hanson, Adrienne R; Birrell, Stephen N; Butler, Lisa M; Hickey, Theresa E; Tilley, Wayne D

    2012-08-01

    Recent evidence indicates that the estrogen receptor-α-negative, androgen receptor (AR)-positive molecular apocrine subtype of breast cancer is driven by AR signaling. The MDA-MB-453 cell line is the prototypical model of this breast cancer subtype; its proliferation is stimulated by androgens such as 5α-dihydrotestosterone (DHT) but inhibited by the progestin medroxyprogesterone acetate (MPA) via AR-mediated mechanisms. We report here that the AR gene in MDA-MB-453 cells contains a G-T transversion in exon 7, resulting in a receptor variant with a glutamine to histidine substitution at amino acid 865 (Q865H) in the ligand binding domain. Compared with wild-type AR, the Q865H variant exhibited reduced sensitivity to DHT and MPA in transactivation assays in MDA-MB-453 and PC-3 cells but did not respond to non-androgenic ligands or receptor antagonists. Ligand binding, molecular modeling, mammalian two-hybrid and immunoblot assays revealed effects of the Q865H mutation on ligand dissociation, AR intramolecular interactions, and receptor stability. Microarray expression profiling demonstrated that DHT and MPA regulate distinct transcriptional programs in MDA-MB-453 cells. Gene Set Enrichment Analysis revealed that DHT- but not MPA-regulated genes were associated with estrogen-responsive transcriptomes from MCF-7 cells and the Wnt signaling pathway. These findings suggest that the divergent proliferative responses of MDA-MB-453 cells to DHT and MPA result from the different genetic programs elicited by these two ligands through the AR-Q865H variant. This work highlights the necessity to characterize additional models of molecular apocrine breast cancer to determine the precise role of AR signaling in this breast cancer subtype. PMID:22719059

  13. A novel prostate cancer therapeutic strategy using icaritin-activated arylhydrocarbon-receptor to co-target androgen receptor and its splice variants

    PubMed Central

    Sun, Feng; Indran, Inthrani R.; Zhang, Zhi Wei; Tan, M.H.Eileen; Li, Yu; Lim, Z.L.Ryan; Hua, Rui; Yang, Chong; Soon, Fen-Fen; Li, Jun; Xu, H.Eric; Cheung, Edwin; Yong, Eu-Leong

    2015-01-01

    Persistent androgen receptor (AR) signaling is the key driving force behind progression and development of castration-resistant prostate cancer (CRPC). In many patients, AR COOH-terminal truncated splice variants (ARvs) play a critical role in contributing to the resistance against androgen depletion therapy. Unfortunately, clinically used antiandrogens like bicalutamide (BIC) and enzalutamide (MDV), which target the ligand binding domain, have failed to suppress these AR variants. Here, we report for the first time that a natural prenylflavonoid, icaritin (ICT), can co-target both persistent AR and ARvs. ICT was found to inhibit transcription of key AR-regulated genes, such as KLK3 [prostate-specific antigen (PSA)] and ARvs-regulated genes, such as UBE2C and induce apoptosis in AR-positive prostate cancer (PC) cells. Mechanistically, ICT promoted the degradation of both AR and ARvs by binding to arylhydrocarbon-receptor (AhR) to mediate ubiquitin-proteasomal degradation. Therefore, ICT impaired AR transactivation in PC cells. Knockdown of AhR gene restored AR stability and partially prevented ICT-induced growth suppression. In clinically relevant murine models orthotopically implanted with androgen-sensitive and CRPC cells, ICT was able to target AR and ARvs, to inhibit AR signaling and tumor growth with no apparent toxicity. Our results provide a mechanistic framework for the development of ICT, as a novel lead compound for AR-positive PC therapeutics, especially for those bearing AR splice variants. PMID:25908644

  14. Prostaglandin receptor EP3 mediates growth inhibitory effect of aspirin through androgen receptor and contributes to castration resistance in prostate cancer cells.

    PubMed

    Kashiwagi, Eiji; Shiota, Masaki; Yokomizo, Akira; Itsumi, Momoe; Inokuchi, Junichi; Uchiumi, Takeshi; Naito, Seiji

    2013-06-01

    Although numerous epidemiological studies show aspirin to reduce risk of prostate cancer, the mechanism of this effect is unclear. Here, we first confirmed that aspirin downregulated androgen receptor (AR) and prostate-specific antigen in prostate cancer cells. We also found that aspirin upregulated prostaglandin receptor subtype EP3 but not EP2 or EP4. The EP3 antagonist L798106 and EP3 knockdown increased AR expression and cell proliferation, whereas the EP3 agonist sulprostone decreased them, indicating that EP3 affects AR expression. Additionally, EP3 (PTGER3) transcript levels were significantly decreased in human prostate cancer tissues compared with those in normal human prostate tissues, suggesting that EP3 is important to prostate carcinogenesis. Decreased EP3 expression was also seen in castration-resistant subtype CxR cells compared with parental LNCaP cells. Finally, we found that aspirin and EP3 modulators affected prostate cancer cell growth. Taken together, aspirin suppressed LNCaP cell proliferation via EP3 signaling activation; EP3 downregulation contributed to prostate carcinogenesis and to progression from androgen-dependent prostate cancer to castration-resistant prostate cancer by regulating AR expression. In conclusion, cyclooxygenases and EP3 may represent attractive therapeutic molecular targets in androgen-dependent prostate cancer. PMID:23493387

  15. Synthesis and biological evaluation of 3-(4-fluorophenyl)-1H-pyrazole derivatives as androgen receptor antagonists.

    PubMed

    Guo, Guangzhu; Liu, Jianzhen; Wang, Guanjie; Zhang, Daoguang; Lu, Jinjie; Zhao, Guisen

    2016-04-01

    A novel series of 3-(4-fluorophenyl)-1H-pyrazole derivatives were synthesized and evaluated for their antiproliferative activity against two prostate cancer cell lines (LNCaP and PC-3) and androgen receptor target gene prostate-specific antigen (PSA) inhibitory activity in LNCaP cells. Several compounds showed potent antiproliferative activity against LNCaP cells and showed a promising PSA downregulation rate. Among these, compound 10e selectively inhibited LNCaP cell growth with an IC50 value of 18 μmol/l and showed a PSA downregulation rate of 46%, which was better than the lead compound T3. PMID:26633887

  16. Prolonged androgen deprivation may influence the autoregulation of estrogen receptors in the brain and pelvic floor muscles of male rats.

    PubMed

    Wibowo, Erik; Calich, Hannah J; Currie, R William; Wassersug, Richard J

    2015-06-01

    Androgen deprivation in males has detrimental effects on various tissues and bodily functions, some of which can be restored by estradiol (E2) administration. We investigated how the duration of androgen deprivation affects the autoregulation of estrogen receptors (ERs) levels in core brain areas associated with sexual behavior and cognition, as well as in pelvic floor muscles (PFM). We also measured c-Fos levels in brain areas associated with sexual behavior shortly after the rats mated. Prolonged castration increases ERα levels in the preoptic area (POA) and E2 treatment reverses these effects. In the POA, c-Fos levels after mating are not affected by the duration of androgen deprivation and/or E2 treatment. ERβ levels in the POA as well as c-Fos levels in the POA and the core area of nucleus accumbens correlate with the mounting frequency for E2-treated Short-Term castrates. Additionally, ERβ levels in the medial amygdala are positively correlated with the mounting frequency of Long-Term castrates that received E2 treatment. In the hippocampus, ERs are downregulated only when E2 is administered early after castration, whereas downregulation of ERα in the prefrontal cortex only occurs with delayed E2 treatment. Early, but not delayed, E2 treatment after castration increases ERβ levels in the bulbocavernosus and ERα levels in the levator ani of male rats. Our data suggest that the duration of androgen deprivation may influence the autoregulation of ERs by E2 treatment in select brain areas and pelvic floor muscles of male rats. PMID:25746452

  17. Novel Stably Transfected Human Reporter Cell Line AIZ-AR as a Tool for an Assessment of Human Androgen Receptor Transcriptional Activity

    PubMed Central

    Bartonkova, Iveta; Novotna, Aneta; Dvorak, Zdenek

    2015-01-01

    Androgen receptor plays multiple physiological and pathological roles in human organism. In the current paper, we describe construction and characterization of a novel stably transfected human reporter cell line AIZ-AR for assessment of transcriptional activity of human androgen receptor. Cell line AIZ-AR is derived from human prostate carcinoma epithelial cell line 22Rv1 that was transfected with reporter plasmid containing 3 copies of androgen response regions (ARRs) followed by a single copy of androgen response element (ARE) from the promoter region of human prostate specific antigen (PSA) gene. AIZ-AR cells remained fully functional for more than 60 days and over 25 passages in the culture and even after cryopreservation. Time-course analyses showed that AIZ-AR cells allow detection of AR ligands as soon as after 8 hours of the treatment. We performed dose-response analyses with 23 steroids in 96-well plate format. We observed activation of AR by androgens, but not by estrogens and mineralocorticoids. Some glucocorticoids and progesterone also induced luciferase, but their potencies were 2-3 orders of magnitude weaker as compared to androgens. Taken together, we have developed a rapid, sensitive, selective, high-throughput and reproducible tool for detection of human AR ligands, with potential use in pharmacological and environmental applications. PMID:25811655

  18. Androgen Receptor Regulation of Vitamin D Receptor in Response of Castration-Resistant Prostate Cancer Cells to 1α-Hydroxyvitamin D5

    PubMed Central

    Mooso, Benjamin; Madhav, Anisha; Johnson, Sherra; Roy, Mohana; Moore, Mary E.; Moy, Christabel; Loredo, Grace A.; Mehta, Rajendra G.; Vaughan, Andrew T.M.; Ghosh, Paramita M.

    2010-01-01

    Calcitriol (1,25(OH)2D3) is cytostatic for prostate cancer (CaP) but had limited therapeutic utility due to hypercalcemia-related toxicities, leading to the development of low-calcemic calcitriol analogs. We show that one analog, 1α-hydroxyvitamin D5 (1α(OH)D5), induced apoptosis in castration-sensitive LNCaP prostate cancer cells but, unlike calcitriol, did not increase androgen receptor (AR) transcriptional activity. LNCaP-AI, a castrate-resistant (CRCaP) LNCaP subline, was resistant to 1α(OH)D5 in the presence of androgens; however, androgen withdrawal (AWD), although ineffective by itself, sensitized LNCaP-AI cells to 1α(OH)D5. Investigation of the mechanism revealed that the vitamin D receptor (VDR), which mediates the effects of 1α(OH)D5, is downregulated in LNCaP-AI cells compared to LNCaP in the presence of androgens, whereas AWD restored VDR expression. Since LNCaP-AI cells expressed higher AR compared to LNCaP and AWD decreased AR, this indicated an inverse relationship between VDR and AR. Further, AR stimulation (by increased androgen) suppressed VDR, while AR downregulation (by ARsiRNA) stimulated VDR levels and sensitized LNCaP-AI cells to 1α(OH)D5 similar to AWD. Another cell line, pRNS-1-1, although isolated from a normal prostate, had lost AR expression in culture and adapted to androgen-independent growth. These cells expressed the VDR and were sensitive to 1α(OH)D5, but restoration of AR expression suppressed VDR levels and induced resistance to 1α(OH)D5 treatment. Taken together, these results demonstrate negative regulation of VDR by AR in CRCaP cells. This effect is likely mediated by prohibitin (PHB), which was inhibited by AR transcriptional activity and stimulated VDR in CRCaP but not castrate-sensitive cells. Therefore, in castration-sensitive cells, although the AR negatively regulates PHB, this does not affect VDR expression, whereas in CRCaP cells, negative regulation of PHB by the AR results in concomitant negative regulation of

  19. Discovery of ODM-201, a new-generation androgen receptor inhibitor targeting resistance mechanisms to androgen signaling-directed prostate cancer therapies.

    PubMed

    Moilanen, Anu-Maarit; Riikonen, Reetta; Oksala, Riikka; Ravanti, Laura; Aho, Eija; Wohlfahrt, Gerd; Nykänen, Pirjo S; Törmäkangas, Olli P; Palvimo, Jorma J; Kallio, Pekka J

    2015-01-01

    Activation of androgen receptor (AR) is crucial for prostate cancer growth. Remarkably, also castration-resistant prostate cancer (CRPC) is dependent on functional AR, and several mechanisms have been proposed to explain the addiction. Known causes of CRPC include gene amplification and overexpression as well as point mutations of AR. We report here the pharmacological profile of ODM-201, a novel AR inhibitor that showed significant antitumor activity and a favorable safety profile in phase 1/2 studies in men with CRPC. ODM-201 is a full and high-affinity AR antagonist that, similar to second-generation antiandrogens enzalutamide and ARN-509, inhibits testosterone-induced nuclear translocation of AR. Importantly, ODM-201 also blocks the activity of the tested mutant ARs arising in response to antiandrogen therapies, including the F876L mutation that confers resistance to enzalutamide and ARN-509. In addition, ODM-201 reduces the growth of AR-overexpressing VCaP prostate cancer cells both in vitro and in a castration-resistant VCaP xenograft model. In contrast to other antiandrogens, ODM-201 shows negligible brain penetrance and does not increase serum testosterone levels in mice. In conclusion, ODM-201 is a potent AR inhibitor that overcomes resistance to AR-targeted therapies by antagonizing both overexpressed and mutated ARs. ODM-201 is currently in a phase 3 trial in CRPC. PMID:26137992

  20. Preparation of Nanobubbles Carrying Androgen Receptor siRNA and Their Inhibitory Effects on Androgen-Independent Prostate Cancer when Combined with Ultrasonic Irradiation

    PubMed Central

    Tan, Kaibin; Guo, Yanli; Tong, Haipeng; Fan, Xiaozhou; Fang, Kejing; Li, Rui

    2014-01-01

    Objective The objective of this study was to investigate nanobubbles carrying androgen receptor (AR) siRNA and their in vitro and in vivo anti-tumor effects, when combined with ultrasonic irradiation, on androgen-independent prostate cancer (AIPC). Materials and Methods Nanobubbles carrying AR siRNA were prepared using poly-L-lysine and electrostatic adsorption methods. Using C4-2 cell activity as a testing index, the optimal irradiation parameters (including the nanobubble number/cell number ratio, mechanical index [MI], and irradiation time) were determined and used for transfection of three human prostate cancer cell lines (C4-2, LNCaP, and PC-3 cells). The AR expression levels were investigated with RT-PCR and Western blot analysis. Additionally, the effects of the nanobubbles and control microbubbles named SonoVue were assessed via imaging in a C4-2 xenograft model. Finally, the growth and AR expression of seven groups of tumor tissues were assessed using the C4-2 xenograft mouse model. Results The nanobubbles had an average diameter of 609.5±15.6 nm and could effectively bind to AR siRNA. Under the optimized conditions of a nanobubble number/cell number ratio of 100∶1, an MI of 1.2, and an irradiation time of 2 min, the highest transfection rates in C4-2, LNCaP, and PC-3 cells were 67.4%, 74.0%, and 63.96%, respectively. In the C4-2 and LNCaP cells, treatment with these binding nanobubbles plus ultrasonic irradiation significantly inhibited cell growth and resulted in the suppression of AR mRNA and protein expression. Additionally, contrast-enhanced ultrasound showed that the nanobubbles achieved stronger signals than the SonoVue control in the central hypovascular area of the tumors. Finally, the anti-tumor effect of these nanobubbles plus ultrasonic irradiation was most significant in the xenograft tumor model compared with the other groups. Conclusion Nanobubbles carrying AR siRNA could be potentially used as gene vectors in combination with ultrasonic

  1. Targeting the human androgen receptor gene with platinated triplex-forming oligonucleotides.

    PubMed

    Graham, Mindy K; Brown, Terry R; Miller, Paul S

    2015-04-01

    Platinum-derivatized homopyrimidine triplex-forming oligonucleotides (Pt-TFOs) consisting of 2'-O-methyl-5-methyluridine, 2'-O-methyl-5-methylcytidine, and a single 3'-N7-trans-chlorodiammine platinum(II)-2'-deoxyguanosine were designed to cross-link to the transcribed strand at four different sequences in the human androgen receptor (AR) gene. Fluorescence microscopy showed that a fluorescein-tagged Pt-TFO localizes in both the cytoplasm and nucleus when it is transfected into LAPC-4 cells, a human prostate cancer cell line, using Lipofectamine 2000. A capture assay employing streptavidin-coated magnetic beads followed by polymerase chain reaction (PCR) amplification was used to demonstrate that 5'-biotin-conjugated Pt-TFOs cross-link in vitro to their four designated AR gene targets in genomic DNA extracted from LAPC-4 cells. Similarly, the