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Sample records for human androgen independent

  1. Mechanisms of Androgen-Independent Prostate Cancer

    PubMed Central

    Saraon, Punit; Drabovich, Andrei P.; Jarvi, Keith A.; Diamandis, Eleftherios P.

    2014-01-01

    Abstract Prostate cancer is the second leading cause of cancer-related deaths among men in North America. Almost all prostate cancers begin in an androgen-dependent state, so androgen deprivation therapy is administered and results in improved clinical outcomes. However, over time, some cancerous cells are able to survive and grow during this treatment, resulting in androgen-independent prostate cancer. At this point, the disease is fatal, as there are no effective targeted therapies available. Most prostate cancer tumors require androgen receptor (AR) signalling for survival. During the progression to androgen-independence, this signalling cascade has been found to be altered at many levels within prostate cancers. Mechanisms that enhance AR signalling during androgen deprivation include: AR gene amplifications, AR gene mutations, changes in expression of AR co-regulatory proteins, changes in expression of steroid-generating enzymes, ligand-independent activation of AR via ‘outlaw’ pathways, and AR-independent pathways that become activated, termed ‘bypass’ pathways. One or more of these aforementioned changes can lead to prostate cancer cells to gain androgen-independent properties. Understanding the molecular alterations that occur during this process will allow for improved therapeutic strategies to target key molecules and pathways important for this progression. PMID:27683456

  2. Mechanisms of Androgen-Independent Prostate Cancer

    PubMed Central

    Saraon, Punit; Drabovich, Andrei P.; Jarvi, Keith A.; Diamandis, Eleftherios P.

    2014-01-01

    Abstract Prostate cancer is the second leading cause of cancer-related deaths among men in North America. Almost all prostate cancers begin in an androgen-dependent state, so androgen deprivation therapy is administered and results in improved clinical outcomes. However, over time, some cancerous cells are able to survive and grow during this treatment, resulting in androgen-independent prostate cancer. At this point, the disease is fatal, as there are no effective targeted therapies available. Most prostate cancer tumors require androgen receptor (AR) signalling for survival. During the progression to androgen-independence, this signalling cascade has been found to be altered at many levels within prostate cancers. Mechanisms that enhance AR signalling during androgen deprivation include: AR gene amplifications, AR gene mutations, changes in expression of AR co-regulatory proteins, changes in expression of steroid-generating enzymes, ligand-independent activation of AR via ‘outlaw’ pathways, and AR-independent pathways that become activated, termed ‘bypass’ pathways. One or more of these aforementioned changes can lead to prostate cancer cells to gain androgen-independent properties. Understanding the molecular alterations that occur during this process will allow for improved therapeutic strategies to target key molecules and pathways important for this progression.

  3. p38MAPK activation is involved in androgen-independent proliferation of human prostate cancer cells by regulating IL-6 secretion

    SciTech Connect

    Shida, Yohei; Igawa, Tsukasa . E-mail: tigawa@net.nagasaki-u.ac.jp; Hakariya, Tomoaki; Sakai, Hideki; Kanetake, Hiroshi

    2007-02-16

    Increased levels of serum interleukin-6 (IL-6) are frequently observed in patients with advanced, hormone-refractory prostate cancer. However, the precise mechanism of IL-6 regulation is still largely unknown. Since prostate cancer gradually progresses to an androgen-independent state despite the stress caused by various therapeutic agents, we hypothesized the stress-activated protein kinases (SAPKs) involvement in androgen-independent growth or IL-6 secretion of prostate cancer cells. Using PC-3 and DU145 human prostate cancer cells, we analyzed the role of SAPKs in IL-6 mediated cell growth and found that the p38MAPK and JNK are involved in androgen-independent cancer cell growth. Furthermore, IL-6 secretion by PC-3 and DU145 cells was significantly suppressed by SAPKs inhibitor, especially by p38MAPK inhibitor SB203580, but not by JNK inhibitor SP600125 nor by MEK inhibitor, PD98059. These results raised the possibility that the IL-6 mediated androgen-independent proliferation of PC-3 and DU145 cells is regulated at least partly via SAPKs signaling pathway especially through p38MAPK activation.

  4. Co-Targeting Prostate Cancer Epithelium and Bone Stroma by Human Osteonectin-Promoter-Mediated Suicide Gene Therapy Effectively Inhibits Androgen-Independent Prostate Cancer Growth.

    PubMed

    Sung, Shian-Ying; Chang, Junn-Liang; Chen, Kuan-Chou; Yeh, Shauh-Der; Liu, Yun-Ru; Su, Yen-Hao; Hsueh, Chia-Yen; Chung, Leland W K; Hsieh, Chia-Ling

    2016-01-01

    Stromal-epithelial interaction has been shown to promote local tumor growth and distant metastasis. We sought to create a promising gene therapy approach that co-targets cancer and its supporting stromal cells for combating castration-resistant prostate tumors. Herein, we demonstrated that human osteonectin is overexpressed in the prostate cancer epithelium and tumor stroma in comparison with their normal counterpart. We designed a novel human osteonectin promoter (hON-522E) containing positive transcriptional regulatory elements identified in both the promoter and exon 1 region of the human osteonectin gene. In vitro reporter assays revealed that the hON-522E promoter is highly active in androgen receptor negative and metastatic prostate cancer and bone stromal cells compared to androgen receptor-positive prostate cancer cells. Moreover, in vivo prostate-tumor-promoting activity of the hON-522E promoter was confirmed by intravenous administration of an adenoviral vector containing the hON-522E promoter-driven luciferase gene (Ad-522E-Luc) into mice bearing orthotopic human prostate tumor xenografts. In addition, an adenoviral vector with the hON-522E-promoter-driven herpes simplex virus thymidine kinase gene (Ad-522E-TK) was highly effective against the growth of androgen-independent human prostate cancer PC3M and bone stromal cell line in vitro and in pre-established PC3M tumors in vivo upon addition of the prodrug ganciclovir. Because of the heterogeneity of human prostate tumors, hON-522E promoter-mediated gene therapy has the potential for the treatment of hormone refractory and bone metastatic prostate cancers.

  5. Co-Targeting Prostate Cancer Epithelium and Bone Stroma by Human Osteonectin-Promoter–Mediated Suicide Gene Therapy Effectively Inhibits Androgen-Independent Prostate Cancer Growth

    PubMed Central

    Sung, Shian-Ying; Chang, Junn-Liang; Chen, Kuan-Chou; Yeh, Shauh-Der; Liu, Yun-Ru; Su, Yen-Hao; Hsueh, Chia-Yen; Chung, Leland W. K.; Hsieh, Chia-Ling

    2016-01-01

    Stromal-epithelial interaction has been shown to promote local tumor growth and distant metastasis. We sought to create a promising gene therapy approach that co-targets cancer and its supporting stromal cells for combating castration-resistant prostate tumors. Herein, we demonstrated that human osteonectin is overexpressed in the prostate cancer epithelium and tumor stroma in comparison with their normal counterpart. We designed a novel human osteonectin promoter (hON-522E) containing positive transcriptional regulatory elements identified in both the promoter and exon 1 region of the human osteonectin gene. In vitro reporter assays revealed that the hON-522E promoter is highly active in androgen receptor negative and metastatic prostate cancer and bone stromal cells compared to androgen receptor-positive prostate cancer cells. Moreover, in vivo prostate-tumor–promoting activity of the hON-522E promoter was confirmed by intravenous administration of an adenoviral vector containing the hON-522E promoter-driven luciferase gene (Ad-522E-Luc) into mice bearing orthotopic human prostate tumor xenografts. In addition, an adenoviral vector with the hON-522E-promoter–driven herpes simplex virus thymidine kinase gene (Ad-522E-TK) was highly effective against the growth of androgen-independent human prostate cancer PC3M and bone stromal cell line in vitro and in pre-established PC3M tumors in vivo upon addition of the prodrug ganciclovir. Because of the heterogeneity of human prostate tumors, hON-522E promoter-mediated gene therapy has the potential for the treatment of hormone refractory and bone metastatic prostate cancers. PMID:27054343

  6. Co-Targeting Prostate Cancer Epithelium and Bone Stroma by Human Osteonectin-Promoter-Mediated Suicide Gene Therapy Effectively Inhibits Androgen-Independent Prostate Cancer Growth.

    PubMed

    Sung, Shian-Ying; Chang, Junn-Liang; Chen, Kuan-Chou; Yeh, Shauh-Der; Liu, Yun-Ru; Su, Yen-Hao; Hsueh, Chia-Yen; Chung, Leland W K; Hsieh, Chia-Ling

    2016-01-01

    Stromal-epithelial interaction has been shown to promote local tumor growth and distant metastasis. We sought to create a promising gene therapy approach that co-targets cancer and its supporting stromal cells for combating castration-resistant prostate tumors. Herein, we demonstrated that human osteonectin is overexpressed in the prostate cancer epithelium and tumor stroma in comparison with their normal counterpart. We designed a novel human osteonectin promoter (hON-522E) containing positive transcriptional regulatory elements identified in both the promoter and exon 1 region of the human osteonectin gene. In vitro reporter assays revealed that the hON-522E promoter is highly active in androgen receptor negative and metastatic prostate cancer and bone stromal cells compared to androgen receptor-positive prostate cancer cells. Moreover, in vivo prostate-tumor-promoting activity of the hON-522E promoter was confirmed by intravenous administration of an adenoviral vector containing the hON-522E promoter-driven luciferase gene (Ad-522E-Luc) into mice bearing orthotopic human prostate tumor xenografts. In addition, an adenoviral vector with the hON-522E-promoter-driven herpes simplex virus thymidine kinase gene (Ad-522E-TK) was highly effective against the growth of androgen-independent human prostate cancer PC3M and bone stromal cell line in vitro and in pre-established PC3M tumors in vivo upon addition of the prodrug ganciclovir. Because of the heterogeneity of human prostate tumors, hON-522E promoter-mediated gene therapy has the potential for the treatment of hormone refractory and bone metastatic prostate cancers. PMID:27054343

  7. Regulation of expression of Na+,K+-ATPase in androgen-dependent and androgen-independent prostate cancer

    PubMed Central

    Blok, L J; Chang, G T G; Steenbeek-Slotboom, M; Weerden, W M van; Swarts, H G P; Pont, J J H H M De; Steenbrugge, G J van; Brinkmann, A O

    1999-01-01

    The β1-subunit of Na+,K+-ATPase was isolated and identified as an androgen down-regulated gene. Expression was observed at high levels in androgen-independent as compared to androgen-dependent (responsive) human prostate cancer cell lines and xenografts when grown in the presence of androgens. Down-regulation of the β1-subunit was initiated at concentrations between 0.01 nM and 0.03 nM of the synthetic androgen R1881 after relatively long incubation times (> 24 h). Using polyclonal antibodies, the concentration of β1-subunit protein, but not of the α1-subunit protein, was markedly reduced in androgen-dependent human prostate cancer cells (LNCaP-FGC) cultured in the presence of androgens. In line with these observations it was found that the protein expression of total Na+,K+-ATPase in the membrane (measured by 3H-ouabain binding) was also markedly decreased. The main function of Na+,K+-ATPase is to maintain sodium and potassium homeostasis in animal cells. The resulting electrochemical gradient is facilitative for transport of several compounds over the cell membrane (for example cisplatin, a chemotherapeutic agent experimentally used in the treatment of hormone-refractory prostate cancer). Here we observed that a ouabain-induced decrease of Na+,K+-ATPase activity in LNCaP-FGC cells results in reduced sensitivity of these cells to cisplatin-treatment. Surprisingly, androgen-induced decrease of Na+,K+-ATPase expression, did not result in significant protection against the chemotherapeutic agent. © 1999 Cancer Research Campaign PMID:10487609

  8. Inhibition of progression of androgen-dependent prostate LNCaP tumors to androgen independence in SCID mice by oral caffeine and voluntary exercise.

    PubMed

    Zheng, Xi; Cui, Xiao-Xing; Huang, Mou-Tuan; Liu, Yue; Wagner, George C; Lin, Yong; Shih, Weichung Joe; Lee, Mao-Jung; Yang, Chung S; Conney, Allan H

    2012-01-01

    The effect of oral caffeine or voluntary running wheel exercise (RW) alone or in combination on the progression of human androgen-dependent LNCaP prostate tumors to androgen independence in male severe combined immunodeficiency mice was determined. The mice were injected subcutaneously with LNCaP cells, and when the tumors reached a moderate size, the mice were surgically castrated and treated with caffeine (0.40 mg/ml drinking water) or RW alone or in combination for 42 days. We found that caffeine administration or RW inhibited the progression and growth of androgen-dependent LNCaP tumors to androgen independence, and a combination of the 2 regimens was more effective than the individual regimens alone. The ratios of the percent mitotic cells/caspase-3 positive cells in tumors from the caffeine-treated, RW-treated, or combination-treated mice were decreased by 34%, 38%, and 52%, respectively. Caffeine treatment increased the percentage of mitotic tumor cells undergoing apoptosis (lethal mitosis) whereas RW inhibited the increase in interleukin-6 that occurred during the progression of LNCaP tumors from androgen dependence to androgen independence. Our results indicate that oral administration of caffeine in combination with voluntary exercise may be an effective strategy for the prevention of prostate cancer progression from androgen dependence to androgen independence. PMID:23061906

  9. 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

  10. Growth hormone-releasing hormone (GHRH) antagonists inhibit the proliferation of androgen-dependent and -independent prostate cancers

    PubMed Central

    Letsch, Markus; Schally, Andrew V.; Busto, Rebeca; Bajo, Ana M.; Varga, Jozsef L.

    2003-01-01

    The antiproliferative effects of an antagonist of growth hormone-releasing hormone (GHRH) JV-1-38 were evaluated in nude mice bearing s.c. xenografts of LNCaP and MDA-PCa-2b human androgen-sensitive and DU-145 androgen-independent prostate cancers. In the androgen-sensitive models, JV-1-38 greatly potentiated the antitumor effect of androgen deprivation induced by surgical castration, but was ineffective when given alone. Thus, in castrated animals bearing MDA-PCa-2b cancers, the administration of JV-1-38 for 35 days virtually arrested tumor growth (94% inhibition vs. intact control, P < 0.01; and 75% vs. castrated control, P < 0.05). The growth of LNCaP tumors was also powerfully suppressed by JV-1-38 combined with castration (83% inhibition vs. intact control, P < 0.01; and 68% vs. castrated control, P < 0.05). However, in androgen-independent DU-145 cancers, JV-1-38 alone could inhibit tumor growth by 57% (P < 0.05) after 45 days. In animals bearing MDA-PCa-2b and LNCaP tumors, the reduction in serum prostate-specific antigen levels, after therapy with JV-1-38, paralleled the decrease in tumor volume. Inhibition of MDA-PCa-2b and DU-145 cancers was associated with the reduction in the expression of mRNA and protein levels of vascular endothelial growth factor. The mRNA expression for GHRH receptor splice variants was found in all these models of prostate cancer. Our results demonstrate that GHRH antagonists inhibit androgen-independent prostate cancers and, after combination with androgen deprivation, also androgen-sensitive tumors. Thus, the therapy with GHRH antagonist could be considered for the management of both androgen-dependent or -independent prostate cancers. PMID:12538852

  11. 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

  12. PRK1/PKN1 controls migration and metastasis of androgen-independent prostate cancer cells.

    PubMed

    Jilg, Cordula A; Ketscher, Anett; Metzger, Eric; Hummel, Barbara; Willmann, Dominica; Rüsseler, Vanessa; Drendel, Vanessa; Imhof, Axel; Jung, Manfred; Franz, Henriette; Hölz, Stefanie; Krönig, Malte; Müller, Judith M; Schüle, Roland

    2014-12-30

    The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor stage, for which no causative cure is available. Here we show that metastatic behavior of androgen-independent prostate tumor cells requires the protein-kinase-C-related kinase (PRK1/PKN1) in vitro and in vivo. PRK1 regulates cell migration and gene expression through its kinase activity, but does not affect cell proliferation. Transcriptome and interactome analyses uncover that PRK1 regulates expression of migration-relevant genes by interacting with the scaffold protein sperm-associated antigen 9 (SPAG9/JIP4). SPAG9 and PRK1 colocalize in human cancer tissue and are required for p38-phosphorylation and cell migration. Accordingly, depletion of either ETS domain-containing protein Elk-1 (ELK1), an effector of p38-signalling or p38 depletion hinders cell migration and changes expression of migration-relevant genes as observed upon PRK1-depletion. Importantly, a PRK1 inhibitor prevents metastases in mice, showing that the PRK1-pathway is a promising target to hamper prostate cancer metastases in vivo. Here we describe a novel mechanism controlling the metastatic behavior of PCa cells and identify PRK1 as a promising therapeutic target to treat androgen-independent metastatic prostate cancer. PMID:25504435

  13. PRK1/PKN1 controls migration and metastasis of androgen-independent prostate cancer cells.

    PubMed

    Jilg, Cordula A; Ketscher, Anett; Metzger, Eric; Hummel, Barbara; Willmann, Dominica; Rüsseler, Vanessa; Drendel, Vanessa; Imhof, Axel; Jung, Manfred; Franz, Henriette; Hölz, Stefanie; Krönig, Malte; Müller, Judith M; Schüle, Roland

    2014-12-30

    The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor stage, for which no causative cure is available. Here we show that metastatic behavior of androgen-independent prostate tumor cells requires the protein-kinase-C-related kinase (PRK1/PKN1) in vitro and in vivo. PRK1 regulates cell migration and gene expression through its kinase activity, but does not affect cell proliferation. Transcriptome and interactome analyses uncover that PRK1 regulates expression of migration-relevant genes by interacting with the scaffold protein sperm-associated antigen 9 (SPAG9/JIP4). SPAG9 and PRK1 colocalize in human cancer tissue and are required for p38-phosphorylation and cell migration. Accordingly, depletion of either ETS domain-containing protein Elk-1 (ELK1), an effector of p38-signalling or p38 depletion hinders cell migration and changes expression of migration-relevant genes as observed upon PRK1-depletion. Importantly, a PRK1 inhibitor prevents metastases in mice, showing that the PRK1-pathway is a promising target to hamper prostate cancer metastases in vivo. Here we describe a novel mechanism controlling the metastatic behavior of PCa cells and identify PRK1 as a promising therapeutic target to treat androgen-independent metastatic prostate cancer.

  14. PRK1/PKN1 controls migration and metastasis of androgen-independent prostate cancer cells

    PubMed Central

    Jilg, Cordula A.; Ketscher, Anett; Metzger, Eric; Hummel, Barbara; Willmann, Dominica; Rüsseler, Vanessa; Drendel, Vanessa; Imhof, Axel; Jung, Manfred; Franz, Henriette; Hölz, Stefanie; Krönig, Malte; Müller, Judith M.; Schüle, Roland

    2014-01-01

    The major threat in prostate cancer is the occurrence of metastases in androgen-independent tumor stage, for which no causative cure is available. Here we show that metastatic behavior of androgen-independent prostate tumor cells requires the protein-kinase-C-related kinase (PRK1/PKN1) in vitro and in vivo. PRK1 regulates cell migration and gene expression through its kinase activity, but does not affect cell proliferation. Transcriptome and interactome analyses uncover that PRK1 regulates expression of migration-relevant genes by interacting with the scaffold protein sperm-associated antigen 9 (SPAG9/JIP4). SPAG9 and PRK1 colocalize in human cancer tissue and are required for p38-phosphorylation and cell migration. Accordingly, depletion of either ETS domain-containing protein Elk-1 (ELK1), an effector of p38-signalling or p38 depletion hinders cell migration and changes expression of migration-relevant genes as observed upon PRK1-depletion. Importantly, a PRK1 inhibitor prevents metastases in mice, showing that the PRK1-pathway is a promising target to hamper prostate cancer metastases in vivo. Statement of significance Here we describe a novel mechanism controlling the metastatic behavior of PCa cells and identify PRK1 as a promising therapeutic target to treat androgen-independent metastatic prostate cancer. PMID:25504435

  15. Androgen actions on the human hair follicle: perspectives.

    PubMed

    Inui, Shigeki; Itami, Satoshi

    2013-03-01

    Androgens stimulate beard growth but suppress hair growth in androgenetic alopecia (AGA). This condition is known as 'androgen paradox'. Human pilosebaceous units possess enough enzymes to form the active androgens testosterone and dihydrotestosterone. In hair follicles, 5α-reductase type 1 and 2, androgen receptors (AR) and AR coactivators can regulate androgen sensitivity of dermal papillae (DP). To regulate hair growth, androgens stimulate production of IGF-1 as positive mediators from beard DP cells and of TGF-β1, TGF-β2, dickkopf1 and IL-6 as negative mediators from balding DP cells. In addition, androgens enhance inducible nitric oxide synthase from occipital DP cells and stem cell factor for positive regulation of hair growth in beard and negative regulation of balding DP cells. Moreover, AGA involves crosstalk between androgen and Wnt/β-catenin signalling. Finally, recent data on susceptibility genes have provided us with the impetus to investigate the molecular pathogenesis of AGA. PMID:23016593

  16. Mechanism of androgen action in cultured dermal papilla cells derived from human hair follicles with varying responses to androgens in vivo.

    PubMed

    Randall, V A; Thornton, M J; Hamada, K; Messenger, A G

    1992-06-01

    Androgens are major regulators of human hair growth, but their effects vary: many follicles are stimulated by androgens, e.g., beard; some remain unaffected, e.g., eyelashes; whereas scalp follicles undergo regression and balding in genetically disposed individuals. Because the dermal papilla controls many aspects of the hair follicle, androgens may act via the dermal papilla, affecting the other follicular components indirectly. In this hypothesis androgens would alter dermal papilla cell production of regulatory substances, e.g., growth factors and/or extracellular matrix components. To test this theory the mechanism of androgen action has been compared in primary lines of dermal papilla cells cultured from androgen-dependent follicles and relatively androgen-independent non-balding scalp. Androgen receptor levels were assayed by saturation analysis (9-10 points; 0.05-10 nmol/l) using the synthetic androgen [3H]-mibolerone and specificity was confirmed by competition studies. Androgen metabolism was investigated both intracellularly and in the media after a 2-h incubation with 5 nM [3H]-testosterone. Carrier and [14C] steroids were added to the extracts before separation by thin-layer chromatography; steroid identity was confirmed by recrystallization. Dermal papilla cells from androgen-dependent follicles contained higher levels of specific, high-affinity, low-capacity androgen receptors than non-balding scalp cells. Testosterone metabolism also varied with beard, public and scalp cells containing testosterone and androstenedione intracellularly, but only beard cells producing 5 alpha-dihydrotestosterone, in line with the scanty beard growth found in 5 alpha-reductase deficiency. Elsewhere we have shown that cultured dermal papilla cells produce extracellular matrix components and mitogenic factors. These results all concur with our original hypothesis and suggest that further studies of such cells may elucidate the paradoxical effects of androgens on human hair

  17. Androgen-independent proliferation of LNCaP prostate cancer cells infected by xenotropic murine leukemia virus-related virus

    SciTech Connect

    Kakoki, Katsura; Kamiyama, Haruka; Izumida, Mai; Yashima, Yuka; Hayashi, Hideki; Yamamoto, Naoki; Matsuyama, Toshifumi; Igawa, Tsukasa; Sakai, Hideki; Kubo, Yoshinao

    2014-04-25

    Highlights: • XMRV infection induces androgen-independent growth in LNCaP cells. • XMRV infection reduces expression of androgen receptor. • XMRV promotes appearance of androgen blocker-resistant prostate cancer cells. - Abstract: Xenotropic murine leukemia virus-related virus (XMRV) is a novel gammaretrovirus that was originally isolated from human prostate cancer. It is now believed that XMRV is not the etiologic agent of prostate cancer. An analysis of murine leukemia virus (MLV) infection in various human cell lines revealed that prostate cancer cell lines are preferentially infected by XMRV, and this suggested that XMRV infection may confer some sort of growth advantage to prostate cancer cell lines. To examine this hypothesis, androgen-dependent LNCaP cells were infected with XMRV and tested for changes in certain cell growth properties. We found that XMRV-infected LNCaP cells can proliferate in the absence of the androgen dihydrotestosterone. Moreover, androgen receptor expression is significantly reduced in XMRV-infected LNCaP cells. Such alterations were not observed in uninfected and amphotropic MLV-infected LNCaP cells. This finding explains why prostate cancer cell lines are preferentially infected with XMRV.

  18. Survival advantage of AMPK activation to androgen-independent prostate cancer cells during energy stress.

    PubMed

    Chhipa, Rishi Raj; Wu, Yue; Mohler, James L; Ip, Clement

    2010-10-01

    Androgen-independent prostate cancer usually develops as a relapse following androgen ablation therapy. Removing androgen systemically causes vascular degeneration and nutrient depletion of the prostate tumor tissue. The fact that the malignancy later evolves to androgen-independence suggests that some cancer cells are able to survive the challenge of energy/nutrient deprivation. AMP-activated protein kinase (AMPK) is an important manager of energy stress. The present study was designed to investigate the role of AMPK in contributing to the survival of the androgen-independent phenotype. Most of the experiments were carried out in the androgen-dependent LNCaP cells and the androgen-independent C4-2 cells. These two cell lines have the same genetic background, since the C4-2 line is derived from the LNCaP line. Glucose deprivation (GD) was instituted to model energy stress encountered by these cells. The key findings are as follows. First, the activation of AMPK by GD was much stronger in C4-2 cells than in LNCaP cells, and the robustness of AMPK activation was correlated favorably with cell viability. Second, the response of AMPK was specific to energy deficiency rather than to amino acid deficiency. The activation of AMPK by GD was functional, as demonstrated by appropriate phosphorylation changes of mTOR and mTOR downstream substrates. Third, blocking AMPK activation by chemical inhibitor or dominant negative AMPK led to increased apoptotic cell death. The observation that similar results were found in other androgen-independent prostate cancer cell lines, including CW22Rv1 abd VCaP, provided further assurance that AMPK is a facilitator on the road to androgen-independence of prostate cancer cells.

  19. LSD1 controls metastasis of androgen-independent prostate cancer cells through PXN and LPAR6

    PubMed Central

    Ketscher, A; Jilg, C A; Willmann, D; Hummel, B; Imhof, A; Rüsseler, V; Hölz, S; Metzger, E; Müller, J M; Schüle, R

    2014-01-01

    Lysine-specific demethylase 1 (LSD1) was shown to control gene expression and cell proliferation of androgen-dependent prostate cancer (PCa) cells, whereas the role of LSD1 in androgen-independent metastatic prostate cancer remains elusive. Here, we show that depletion of LSD1 leads to increased migration and invasion of androgen-independent PCa cells. Transcriptome and cistrome analyses reveal that LSD1 regulates expression of lysophosphatidic acid receptor 6 (LPAR6) and cytoskeletal genes including the focal adhesion adaptor protein paxillin (PXN). Enhanced LPAR6 signalling upon LSD1 depletion promotes migration with concomitant phosphorylation of PXN. In mice LPAR6 overexpression enhances, whereas knockdown of LPAR6 abolishes metastasis of androgen-independent PCa cells. Taken together, we uncover a novel mechanism of how LSD1 controls metastasis and identify LPAR6 as a promising therapeutic target to treat metastatic prostate cancer. PMID:25285406

  20. 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

  1. 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.

  2. 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

  3. Expression of androgen and progesterone receptors in primary human meningiomas.

    PubMed

    Maxwell, M; Galanopoulos, T; Neville-Golden, J; Antoniades, H N

    1993-03-01

    Meningiomas are common brain tumors that show a predilection for females and become more aggressive during pregnancy and menses. The existence of gender-specific hormone receptors in meningiomas has long been a matter of controversy; the recent cloning of androgen, estrogen, and progesterone receptors has facilitated their direct evaluation. The authors have demonstrated the expression of androgen and progesterone receptor messenger ribonucleic acid and protein product in nine primary human meningiomas by Northern blot analysis. Cellular localization was achieved by in situ hybridization analysis. Estrogen receptor expression was not detected. Normal adult meninges were shown to express very low levels of both androgen and progesterone receptors.

  4. Androgens in human evolution. A new explanation of human evolution.

    PubMed

    Howard, J

    2001-01-01

    Human evolution consists of chronological changes in gene regulation of a continuous and relatively stable genome, activated by hormones, the production of which is intermittently affected by endogenous and exogenous forces. Periodic variations in the gonadal androgen, testosterone, and the adrenal androgen, dehydroepiandrosterone (DHEA), significantly participated in all hominid transformations. The hominid characteristics of early Australopithecines are primarily a result of increased testosterone. The first significant cold of the early Pleistocene resulted in an increase in DHEA that simultaneously produced Homo and the robust Australopithecines. Subsequent Pleistocene climatic changes and differential reproduction produced changes in DHEA and testosterone ratios that caused extinction of the robust Australopithecines and further changes and continuation of Homo. Changes in testosterone and DHEA produce allometric and behavioral changes that are identifiable and vigorous in modern populations. PMID:11702658

  5. Androgens in human evolution. A new explanation of human evolution.

    PubMed

    Howard, J

    2001-01-01

    Human evolution consists of chronological changes in gene regulation of a continuous and relatively stable genome, activated by hormones, the production of which is intermittently affected by endogenous and exogenous forces. Periodic variations in the gonadal androgen, testosterone, and the adrenal androgen, dehydroepiandrosterone (DHEA), significantly participated in all hominid transformations. The hominid characteristics of early Australopithecines are primarily a result of increased testosterone. The first significant cold of the early Pleistocene resulted in an increase in DHEA that simultaneously produced Homo and the robust Australopithecines. Subsequent Pleistocene climatic changes and differential reproduction produced changes in DHEA and testosterone ratios that caused extinction of the robust Australopithecines and further changes and continuation of Homo. Changes in testosterone and DHEA produce allometric and behavioral changes that are identifiable and vigorous in modern populations.

  6. Piperine, a Bioactive Component of Pepper Spice Exerts Therapeutic Effects on Androgen Dependent and Androgen Independent Prostate Cancer Cells

    PubMed Central

    Dakshinamoorthy, Gajalakshmi; Bartik, Mary Margaret; Johnson, Gary Leon; Webb, Brian; Zheng, Guoxing; Chen, Aoshuang; Kalyanasundaram, Ramaswamy; Munirathinam, Gnanasekar

    2013-01-01

    Prostate cancer is the most common solid malignancy in men, with 32,000 deaths annually. Piperine, a major alkaloid constituent of black pepper, has previously been reported to have anti-cancer activity in variety of cancer cell lines. The effect of piperine against prostate cancer is not currently known. Therefore, in this study, we investigated the anti-tumor mechanisms of piperine on androgen dependent and androgen independent prostate cancer cells. Here, we show that piperine inhibited the proliferation of LNCaP, PC-3, 22RV1 and DU-145 prostate cancer cells in a dose dependent manner. Furthermore, Annexin-V staining demonstrated that piperine treatment induced apoptosis in hormone dependent prostate cancer cells (LNCaP). Using global caspase activation assay, we show that piperine-induced apoptosis resulted in caspase activation in LNCaP and PC-3 cells. Further studies revealed that piperine treatment resulted in the activation of caspase-3 and cleavage of PARP-1 proteins in LNCaP, PC-3 and DU-145 prostate cancer cells. Piperine treatment also disrupted androgen receptor (AR) expression in LNCaP prostate cancer cells. Our evaluations further show that there is a significant reduction of Prostate Specific Antigen (PSA) levels following piperine treatment in LNCaP cells. NF-kB and STAT-3 transcription factors have previously been shown to play a role in angiogenesis and invasion of prostate cancer cells. Interestingly, treatment of LNCaP, PC-3 and DU-145 prostate cancer cells with piperine resulted in reduced expression of phosphorylated STAT-3 and Nuclear factor-κB (NF-kB) transcription factors. These results correlated with the results of Boyden chamber assay, wherein piperine treatment reduced the cell migration of LNCaP and PC-3 cells. Finally, we show that piperine treatment significantly reduced the androgen dependent and androgen independent tumor growth in nude mice model xenotransplanted with prostate cancer cells. Taken together, these results support

  7. Autoimmune anti-androgen-receptor antibodies in human serum.

    PubMed Central

    Liao, S; Witte, D

    1985-01-01

    Circulating autoantibodies to human and rat androgen receptors are present at high titers in the blood sera of some patients with prostate diseases. The antibodies from some serum samples were associated with a purified IgG fraction and interacted with the 3.8S cytosolic androgen-receptor complexes of rat ventral prostate to form 9- to 12S units. Other serum samples, however, formed 14- to 19S units, suggesting that other immunoglobulins might be involved. In the presence of an anti-human immunoglobulin as a second antibody, the androgen-receptor-antibody complexes could be immunoprecipitated. The antibodies interacted with the nuclear and the cytosolic androgen-receptor complexes, either the DNA-binding or the nonbinding form, but not with receptors for estradiol, progestin, or dexamethasone from a variety of sources. Human testosterone/estradiol-binding globulin, rat epididymal androgen-binding protein, or rat prostate alpha-protein (a nonreceptor steroid-binding protein) also did not interact with the antibodies to form immunoprecipitates. About 37% of male and 3% of female serum samples screened had significant antibody titer. The chance of finding serum with a high titer is much better in males older than 66 years than in the younger males or females at all ages. The presence of the high-titer antibodies may make it possible to prepare monoclonal antibodies to androgen receptors without purification of the receptors for immunization. PMID:3866227

  8. Histological changes caused by meclofenamic acid in androgen independent prostate cancer tumors: evaluation in a mouse model

    PubMed Central

    Delgado-Enciso, Iván; Soriano-Hernández, Alejandro D.; Rodriguez-Hernandez, Alejandrina; Galvan-Salazar, Héctor R.; Montes-Galindo, Daniel A.; Martinez-Martinez, Rafael; Valdez-Velazquez, Laura L.; Gonzalez-Alvarez, Rafael; Espinoza-Gómez, Francisco; Newton-Sanchez, Oscar A.; Lara-Esqueda, Agustín; Guzman-Esquivel, Jose

    2015-01-01

    ABSTRACT Meclofenamic acid is a nonsteroidal anti-inflammatory drug that has shown therapeutic potential for different types of cancers, including androgen-independent prostate neoplasms. The antitumor effect of diverse nonsteroidal anti-inflammatory drugs has been shown to be accompanied by histological and molecular changes that are responsible for this beneficial effect. The objective of the present work was to analyze the histological changes caused by meclofenamic acid in androgen-independent prostate cancer. Tumors were created in a nude mouse model using PC3 cancerous human cells. Meclofenamic acid (10 mg/kg/day; experimental group, n=5) or saline solution (control group, n=5) was administered intraperitoneally for twenty days. Histological analysis was then carried out on the tumors, describing changes in the cellular architecture, fibrosis, and quantification of cellular proliferation and tumor vasculature. Meclofenamic acid causes histological changes that indicate less tumor aggression (less hypercellularity, fewer atypical mitoses, and fewer nuclear polymorphisms), an increase in fibrosis, and reduced cellular proliferation and tumor vascularity. Further studies are needed to evaluate the molecular changes that cause the beneficial and therapeutic effects of meclofenamic acid in androgen-independent prostate cancer. PMID:26689527

  9. The CXCL12/CXCR4 axis promotes ligand-independent activation of the androgen receptor.

    PubMed

    Kasina, Sathish; Macoska, Jill A

    2012-04-01

    The molecular mechanisms responsible for the transition of some prostate cancers from androgen ligand-dependent to androgen ligand-independent are incompletely established. Molecules that are ligands for G protein coupled receptors (GPCRs) have been implicated in ligand-independent androgen receptor (AR) activation. The purpose of this study was to examine whether CXCL12, the ligand for the GPCR, CXCR4, might mediate prostate cancer cell proliferation through AR-dependent mechanisms involving functional transactivation of the AR in the absence of androgen. The results of these studies showed that activation of the CXCL12/CXCR4 axis promoted: The nuclear accumulation of both wild-type and mutant AR in several prostate epithelial cell lines; AR-dependent proliferative responses; nuclear accumulation of the AR co-regulator SRC-1 protein; SRC-1:AR protein:protein association; co-localization of AR and SRC-1 on the promoters of AR-regulated genes; AR- and SRC-1 dependent transcription of AR-regulated genes; AR-dependent secretion of the AR-regulated PSA protein; P13K-dependent phosphorylation of AR; MAPK-dependent phosphorylation of SRC-1, and both MAPK- and P13K-dependent secretion of the PSA protein, in the absence of androgen. Taken together, these studies identify CXCL12 as a novel, non-steroidal growth factor that promotes the growth of prostate epithelial cells through AR-dependent mechanisms in the absence of steroid hormones. These findings support the development of novel therapeutics targeting the CXCL12/CXCR4 axis as an ancillary to those targeting the androgen/AR axis to effectively treat castration resistant/recurrent prostate tumors.

  10. 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 ...

  11. 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...

  12. Anogenital distance as a marker of androgen exposure in humans.

    PubMed

    Thankamony, A; Pasterski, V; Ong, K K; Acerini, C L; Hughes, I A

    2016-07-01

    Abnormal foetal testis development has been proposed to underlie common disorders of the male reproductive system such as cryptorchidism, hypospadias, reduced semen quality and testicular germ cell tumour, which are regarded as components of a 'testicular dysgenesis syndrome'. The increasing trends and geographical variation in their incidence have been suggested to result from in utero exposure to environmental chemicals acting as endocrine disruptors. In rodents, the anogenital distance (AGD), measured from the anus to the base of genital tubercle, is a sensitive biomarker of androgen exposure during a critical embryonic window of testis development. In humans, several epidemiological studies have shown alterations in AGD associated with prenatal exposure to several chemicals with potential endocrine disrupting activity. However, the link between AGD and androgen exposure in humans is not well-defined. This review focuses on the current evidence for such a relationship. As in rodents, a clear gender difference is detected during foetal development of the AGD in humans which is maintained thereafter. Reduced AGD in association with clinically relevant outcomes of potential environmental exposures, such as cryptorchidism or hypospadias, is in keeping with AGD as a marker of foetal testicular function. Furthermore, AGD may reflect variations in prenatal androgen exposure in healthy children as shorter AGD at birth is associated with reduced masculine play behaviour in preschool boys. Several studies provide evidence linking shorter AGD with lower fertility, semen quality and testosterone levels in selected groups of adults attending andrology clinics. Overall, the observational data in humans are consistent with experimental studies in animals and support the use of AGD as a biomarker of foetal androgen exposure. Future studies evaluating AGD in relation to reproductive hormones in both infants and adults, and to gene polymorphisms, will help to further delineate

  13. Photoperiod modulation of aggressive behavior is independent of androgens in a tropical cichlid fish.

    PubMed

    Gonçalves-de-Freitas, Eliane; Carvalho, Thaís Billalba; Oliveira, Rui F

    2014-10-01

    Photoperiod is a major environmental cue that signals breeding conditions in animals living in temperate climates. Therefore, the activity of the reproductive (i.e. hypothalamic-pituitary-gonadal, HPG) axis and of the expression of reproductive behaviors, including territoriality, is responsive to changes in day length. However, at low latitudes the seasonal variation in day length decreases dramatically and photoperiod becomes less reliable as a breeding entraining cue in tropical species. In spite of this, some tropical mammals and birds have been found to still respond to small amplitude changes in photoperiod (e.g. 17min). Here we tested the effect of 2 photoperiod regimes, referred to as long-day (LD: 16L:08D) and short-day (SD: 08L:16D), on the activity of the HPG axis, on aggressive behavior and in the androgen response to social challenges in males of the tropical cichlid fish Tilapia rendalli. For each treatment, fish were transferred from a pre-treatment photoperiod of 12L:12D to their treatment photoperiod (either LD or SD) in which they were kept for 20days on stock tanks. Afterwards, males were isolated for 4days in glass aquaria in order to establish territories and initial androgen levels (testosterone, T; 11-ketotestosterone, KT) were assessed. On the 4th day, territorial intrusions were promoted such that 1/3 of the isolated males acted as residents and another 1/3 as intruders. Territorial intrusions lasted for 1h to test the effects of a social challenge under different photoperiod regimes. Photoperiod treatment (either SD or LD) failed to induce significant changes in the HPG activity, as measured by androgen levels and gonadosomatic index. However, SD increased the intensity of aggressive behaviors and shortened the time to settle a dominance hierarchy in an androgen-independent manner. The androgen responsiveness to the simulated territorial intrusion was only present in KT but not for T. The percent change in KT levels in response to the

  14. Photoperiod modulation of aggressive behavior is independent of androgens in a tropical cichlid fish.

    PubMed

    Gonçalves-de-Freitas, Eliane; Carvalho, Thaís Billalba; Oliveira, Rui F

    2014-10-01

    Photoperiod is a major environmental cue that signals breeding conditions in animals living in temperate climates. Therefore, the activity of the reproductive (i.e. hypothalamic-pituitary-gonadal, HPG) axis and of the expression of reproductive behaviors, including territoriality, is responsive to changes in day length. However, at low latitudes the seasonal variation in day length decreases dramatically and photoperiod becomes less reliable as a breeding entraining cue in tropical species. In spite of this, some tropical mammals and birds have been found to still respond to small amplitude changes in photoperiod (e.g. 17min). Here we tested the effect of 2 photoperiod regimes, referred to as long-day (LD: 16L:08D) and short-day (SD: 08L:16D), on the activity of the HPG axis, on aggressive behavior and in the androgen response to social challenges in males of the tropical cichlid fish Tilapia rendalli. For each treatment, fish were transferred from a pre-treatment photoperiod of 12L:12D to their treatment photoperiod (either LD or SD) in which they were kept for 20days on stock tanks. Afterwards, males were isolated for 4days in glass aquaria in order to establish territories and initial androgen levels (testosterone, T; 11-ketotestosterone, KT) were assessed. On the 4th day, territorial intrusions were promoted such that 1/3 of the isolated males acted as residents and another 1/3 as intruders. Territorial intrusions lasted for 1h to test the effects of a social challenge under different photoperiod regimes. Photoperiod treatment (either SD or LD) failed to induce significant changes in the HPG activity, as measured by androgen levels and gonadosomatic index. However, SD increased the intensity of aggressive behaviors and shortened the time to settle a dominance hierarchy in an androgen-independent manner. The androgen responsiveness to the simulated territorial intrusion was only present in KT but not for T. The percent change in KT levels in response to the

  15. Activation of two mutant androgen receptors from human prostatic carcinoma by adrenal androgens and metabolic derivatives of testosterone.

    PubMed

    Culig, Z; Stober, J; Gast, A; Peterziel, H; Hobisch, A; Radmayr, C; Hittmair, A; Bartsch, G; Cato, A C; Klocker, H

    1996-01-01

    The androgen receptor (AR) plays a central regulatory role in prostatic carcinoma and is a target of androgen ablation therapy. Recent detection of mutant receptors in tumor specimens suggest a contribution of AR alterations to progression towards androgen independence. In a specimen derived from metastatic prostate cancer we have reported a point mutation in the AR gene that leads to a single amino acid exchange in the ligand binding domain of the receptor. Another amino acid exchange resulting from a point mutation was also identified 15 amino acids away from our mutation. This mutation was detected in the AR gene isolated from an organ-confined prostatic tumor. Here we report the functional characterization of the two mutant receptors in the presence of adrenal androgens and testosterone metabolites. These studies were performed by cotransfecting androgen-responsive reporter genes and either the wild-type or mutant AR expression vectors into receptor negative DU-145 and CV-1 cells. The indicator genes used consisted of the promoter of the androgen-inducible prostate-specific antigen gene or the C' Delta9 enhancer fragment from the promoter of the mouse sex-limited protein driving the expression of the bacterial chloramphenicol acetyl transferase gene. Cotransfection-transactivation assays revealed that the adrenal androgen androstenedione and two products of testosterone metabolism, androsterone and androstandiol, induced reporter gene activity more efficiently in the presence of the mutant receptors than in the presence of the wild-type receptor. No difference between wild-type and mutant receptors was observed in the presence of the metabolite androstandione. The interaction of receptor-hormone complexes with target DNA was studied in vitro by electrophoretic mobility shift assays (EMSA). Dihydrotestosterone and the synthetic androgen mibolerone induced a faster migrating complex with all receptors, whereas the androgen metabolite androstandione induced this

  16. Endocrine differentiation of fetal ovaries and testes of the spotted hyena (Crocuta crocuta): timing of androgen-independent versus androgen-driven genital development.

    PubMed

    Browne, P; Place, N J; Vidal, J D; Moore, I T; Cunha, G R; Glickman, S E; Conley, A J

    2006-10-01

    Female spotted hyenas (Crocuta crocuta) have an erectile peniform clitoris and a pseudoscrotum but no external vagina, all established by day 35 of a 110-day gestation. Recent studies indicate that these events are androgen-independent, although androgen secretion by fetal ovaries and testis was hypothesized previously to induce phallic development in both sexes. We present the first data relating to the capacity of the ovaries and testes of the spotted hyena to synthesize androgens at different stages of fetal life. Specifically, spotted hyena fetal gonads were examined by immunohistochemistry at GD 30, 45, 48, 65, and 95 for androgen-synthesizing enzymes, as related to the morphological development. Enzymes included 17alpha-hydroxylase/17,20-lyase cytochrome P450 (P450c17), cytochrome b5, 3beta-hydroxysteroid dehydrogenase (3betaHSD), and cholesterol side-chain cleavage cytochrome P450 (P450scc). Anti-Müllerian-hormone (AMH) expression was also examined. AMH was strongly expressed in fetal Sertoli cells from GD 30 and after. P450c17 expression was detected in Leydig cells of developing testes and surprisingly in Müllerian duct epithelium. Fetal ovaries began to organize and differentiate by GD 45, and medullary cells expressed P450c17, cytochrome b5, 3betaHSD, and P450scc. The findings support the hypothesis that external genital morphology is probably androgen-independent initially, but that fetal testicular androgens modify the secondary, male-specific phallic form and accessory organs. Fetal ovaries appear to develop substantial androgen-synthesizing capacity but not until phallic differentiation is complete, i.e. after GD 45 based on circulating androstenedione concentrations. During late gestation, fetal ovaries and testes synthesize androgens, possibly organizing the neural substrates of aggressive behaviors observed at birth in spotted hyenas. These data provide an endocrine rationale for sexual dimorphisms in phallic structure and reveal a potential

  17. Cell-specific activation of the human skeletal alpha-actin by androgens.

    PubMed

    Hong, Mei Hua; Sun, Hong; Jin, Cheng He; Chapman, Mark; Hu, Junlian; Chang, William; Burnett, Kelven; Rosen, Jon; Negro-Vilar, Andres; Miner, Jeffrey N

    2008-03-01

    Although it is evident that androgens increase muscle mass and strength, little is known about the critical molecular targets of androgens in skeletal muscle. In rodents, the skeletal alpha-actin gene is a tissue-specific gene expressed only in the levator ani and other skeletal muscles but not in the prostate or preputial gland, the well-known androgen target tissue. We identified tissue-specific androgen-regulated genes in the skeletal muscle in rats after oral administration of androgens and focused on androgen-dependent up-regulation of the skeletal alpha-actin gene. To investigate the mechanism of action, an in vitro system with various cell lines and a series of deletion mutants of the alpha-actin promoter were used. The human skeletal alpha-actin promoter was activated by androgens in the muscle cell line C2C12 but not in the liver, prostate, or breast cancer cell lines in which exogenous human androgen receptor is expressed. The sequence of the promoter is sufficient for cell-specific androgen response, providing a model for the tissue specificity demonstrated in vivo. Using a series of deletion mutants, the androgen response can be maintained using just the proximal promoter region. The importance of androgen regulation of this small portion of the human skeletal alpha-actin promoter was demonstrated by the correlation between muscle and the alpha-actin promoter activity for an array of selective androgen receptor modulators (SARMs), including an orally active SARM LGD2226. Taken together, the results suggest that the regulation of skeletal alpha-actin by androgens/SARMs may represent an important model system for understanding androgen anabolic action in the muscle.

  18. Phosphoproteome analysis demonstrates the potential role of THRAP3 phosphorylation in androgen-independent prostate cancer cell growth.

    PubMed

    Ino, Yoko; Arakawa, Noriaki; Ishiguro, Hitoshi; Uemura, Hiroji; Kubota, Yoshinobu; Hirano, Hisashi; Toda, Tosifusa

    2016-04-01

    Elucidating the androgen-independent growth mechanism is critical for developing effective treatment strategies to combat androgen-independent prostate cancer. We performed a comparative phosphoproteome analysis using a prostate cancer cell line, LNCaP, and an LNCaP-derived androgen-independent cell line, LNCaP-AI, to identify phosphoproteins involved in this mechanism. We performed quantitative comparisons of the phosphopeptide levels in tryptic digests of protein extracts from these cell lines using MS. We found that the levels of 69 phosphopeptides in 66 proteins significantly differed between LNCaP and LNCaP-AI. In particular, we focused on thyroid hormone receptor associated protein 3 (THRAP3), which is a known transcriptional coactivator of the androgen receptor. The phosphorylation level of THRAP3 was significantly lower at S248 and S253 in LNCaP-AI cells. Furthermore, pull-down assays showed that 32 proteins uniquely bound to the nonphosphorylatable mutant form of THRAP3, whereas 31 other proteins uniquely bound to the phosphorylation-mimic form. Many of the differentially interacting proteins were identified as being involved with RNA splicing and processing. These results suggest that the phosphorylation state of THRAP3 at S248 and S253 might be involved in the mechanism of androgen-independent prostate cancer cell growth by changing the interaction partners.

  19. Androgen and taxol cause cell type-specific alterations of centrosome and DNA organization in androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cells

    NASA Technical Reports Server (NTRS)

    Schatten, H.; Ripple, M.; Balczon, R.; Weindruch, R.; Chakrabarti, A.; Taylor, M.; Hueser, C. N.

    2000-01-01

    We investigated the effects of androgen and taxol on the androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cell lines. Cells were treated for 48 and 72 h with 0.05-1 nM of the synthetic androgen R1881 and with 100 nM taxol. Treatment of LNCaP cells with 0.05 nM R1881 led to increased cell proliferation, whereas treatment with 1 nM R1881 resulted in inhibited cell division, DNA cycle arrest, and altered centrosome organization. After treatment with 1 nM R1881, chromatin became clustered, nuclear envelopes convoluted, and mitochondria accumulated around the nucleus. Immunofluorescence microscopy with antibodies to centrosomes showed altered centrosome structure. Although centrosomes were closely associated with the nucleus in untreated cells, they dispersed into the cytoplasm after treatment with 1 nM R1881. Microtubules were only faintly detected in 1 nM R1881-treated LNCaP cells. The effects of taxol included microtubule bundling and altered mitochondria morphology, but not DNA organization. As expected, the androgen-independent prostate cancer cell line DU145 was not affected by R1881. Treatment with taxol resulted in bundling of microtubules in both cell lines. Additional taxol effects were seen in DU145 cells with micronucleation of DNA, an indication of apoptosis. Simultaneous treatment with R1881 and taxol had no additional effects on LNCaP or DU145 cells. These results suggest that LNCaP and DU145 prostate cancer cells show differences not only in androgen responsiveness but in sensitivity to taxol as well. Copyright 2000 Wiley-Liss, Inc.

  20. Androgens and Male Sexual Function: A Review of Human Studies

    ERIC Educational Resources Information Center

    Schiavi, Raul C.; White, Daniel

    1976-01-01

    The scope of this article is a review and brief discussion of recently gathered information on androgens and sexual behavior in men. Current pharmacological research does not furnish specific evidence that administration of androgens or preprations that stimulate the secretion of endogenous androgens have beneficial effects on functional…

  1. A New Murine Model of Osteoblastic/Osteolytic Lesions from Human Androgen-Resistant Prostate Cancer

    PubMed Central

    Depalle, Baptiste; Serre, Claire Marie; Farlay, Delphine; Turtoi, Andrei; Bellahcene, Akeila; Follet, Hélène; Castronovo, Vincent; Clézardin, Philippe; Bonnelye, Edith

    2013-01-01

    Background Up to 80% of patients dying from prostate carcinoma have developed bone metastases that are incurable. Castration is commonly used to treat prostate cancer. Although the disease initially responds to androgen blockade strategies, it often becomes castration-resistant (CRPC for Castration Resistant Prostate Cancer). Most of the murine models of mixed lesions derived from prostate cancer cells are androgen sensitive. Thus, we established a new model of CRPC (androgen receptor (AR) negative) that causes mixed lesions in bone. Methods PC3 and its derived new cell clone PC3c cells were directly injected into the tibiae of SCID male mice. Tumor growth was analyzed by radiography and histology. Direct effects of conditioned medium of both cell lines were tested on osteoclasts, osteoblasts and osteocytes. Results We found that PC3c cells induced mixed lesions 10 weeks after intratibial injection. In vitro, PC3c conditioned medium was able to stimulate tartrate resistant acid phosphatase (TRAP)-positive osteoclasts. Osteoprotegerin (OPG) and endothelin-1 (ET1) were highly expressed by PC3c while dikkopf-1 (DKK1) expression was decreased. Finally, PC3c highly expressed bone associated markers osteopontin (OPN), Runx2, alkaline phosphatase (ALP), bone sialoprotein (BSP) and produced mineralized matrix in vitro in osteogenic conditions. Conclusions We have established a new CRPC cell line as a useful system for modeling human metastatic prostate cancer which presents the mixed phenotype of bone metastases that is commonly observed in prostate cancer patients with advanced disease. This model will help to understand androgen-independent mechanisms involved in the progression of prostate cancer in bone and provides a preclinical model for testing the effects of new treatments for bone metastases. PMID:24069383

  2. ANABOLIC-ANDROGENIC STEROID DEPENDENCE? INSIGHTS FROM ANIMALS AND HUMANS

    PubMed Central

    Wood, Ruth I.

    2008-01-01

    Anabolic-androgenic steroids (AAS) are drugs of abuse. They are taken in large quantities by athletes and others to increase performance, with negative health consequences. As a result, in 1991 testosterone and related AAS were declared controlled substances. However, the relative abuse and dependence liability of AAS have not been fully characterized. In humans, it is difficult to separate the direct psychoactive effects of AAS from reinforcement due to their systemic anabolic effects. However, using conditioned place preference and self-administration, studies in animals have demonstrated that AAS are reinforcing in a context where athletic performance is irrelevant. Furthermore, AAS share brain sites of action and neurotransmitter systems in common with other drugs of abuse. In particular, recent evidence links AAS with opioids. In humans, AAS abuse is associated with prescription opioid use. In animals, AAS overdose produces symptoms resembling opioid overdose, and AAS modify the activity of the endogenous opioid system. PMID:18275992

  3. Anabolic-androgenic steroid dependence? Insights from animals and humans.

    PubMed

    Wood, Ruth I

    2008-10-01

    Anabolic-androgenic steroids (AAS) are drugs of abuse. They are taken in large quantities by athletes and others to increase performance, with negative health consequences. As a result, in 1991 testosterone and related AAS were declared controlled substances. However, the relative abuse and dependence liability of AAS have not been fully characterized. In humans, it is difficult to separate the direct psychoactive effects of AAS from reinforcement due to their systemic anabolic effects. However, using conditioned place preference and self-administration, studies in animals have demonstrated that AAS are reinforcing in a context where athletic performance is irrelevant. Furthermore, AAS share brain sites of action and neurotransmitter systems in common with other drugs of abuse. In particular, recent evidence links AAS with opioids. In humans, AAS abuse is associated with prescription opioid use. In animals, AAS overdose produces symptoms resembling opioid overdose, and AAS modify the activity of the endogenous opioid system.

  4. Position stand on androgen and human growth hormone use.

    PubMed

    Hoffman, Jay R; Kraemer, William J; Bhasin, Shalender; Storer, Thomas; Ratamess, Nicholas A; Haff, G Gregory; Willoughby, Darryn S; Rogol, Alan D

    2009-08-01

    Hoffman, JR, Kraemer, WJ, Bhasin, S, Storer, T, Ratamess, NA, Haff, GG, Willoughby, DS, and Rogol, AD. Position stand on Androgen and human growth hormone use. J Strength Cond Res 23(5): S1-S59, 2009-Perceived yet often misunderstood demands of a sport, overt benefits of anabolic drugs, and the inability to be offered any effective alternatives has fueled anabolic drug abuse despite any consequences. Motivational interactions with many situational demands including the desire for improved body image, sport performance, physical function, and body size influence and fuel such negative decisions. Positive countermeasures to deter the abuse of anabolic drugs are complex and yet unclear. Furthermore, anabolic drugs work and the optimized training and nutritional programs needed to cut into the magnitude of improvement mediated by drug abuse require more work, dedication, and preparation on the part of both athletes and coaches alike. Few shortcuts are available to the athlete who desires to train naturally. Historically, the NSCA has placed an emphasis on education to help athletes, coaches, and strength and conditioning professionals become more knowledgeable, highly skilled, and technically trained in their approach to exercise program design and implementation. Optimizing nutritional strategies are a vital interface to help cope with exercise and sport demands (). In addition, research-based supplements will also have to be acknowledged as a strategic set of tools (e.g., protein supplements before and after resistance exercise workout) that can be used in conjunction with optimized nutrition to allow more effective adaptation and recovery from exercise. Resistance exercise is the most effective anabolic form of exercise, and over the past 20 years, the research base for resistance exercise has just started to develop to a significant volume of work to help in the decision-making process in program design (). The interface with nutritional strategies has been less

  5. Position stand on androgen and human growth hormone use.

    PubMed

    Hoffman, Jay R; Kraemer, William J; Bhasin, Shalender; Storer, Thomas; Ratamess, Nicholas A; Haff, G Gregory; Willoughby, Darryn S; Rogol, Alan D

    2009-08-01

    Hoffman, JR, Kraemer, WJ, Bhasin, S, Storer, T, Ratamess, NA, Haff, GG, Willoughby, DS, and Rogol, AD. Position stand on Androgen and human growth hormone use. J Strength Cond Res 23(5): S1-S59, 2009-Perceived yet often misunderstood demands of a sport, overt benefits of anabolic drugs, and the inability to be offered any effective alternatives has fueled anabolic drug abuse despite any consequences. Motivational interactions with many situational demands including the desire for improved body image, sport performance, physical function, and body size influence and fuel such negative decisions. Positive countermeasures to deter the abuse of anabolic drugs are complex and yet unclear. Furthermore, anabolic drugs work and the optimized training and nutritional programs needed to cut into the magnitude of improvement mediated by drug abuse require more work, dedication, and preparation on the part of both athletes and coaches alike. Few shortcuts are available to the athlete who desires to train naturally. Historically, the NSCA has placed an emphasis on education to help athletes, coaches, and strength and conditioning professionals become more knowledgeable, highly skilled, and technically trained in their approach to exercise program design and implementation. Optimizing nutritional strategies are a vital interface to help cope with exercise and sport demands (). In addition, research-based supplements will also have to be acknowledged as a strategic set of tools (e.g., protein supplements before and after resistance exercise workout) that can be used in conjunction with optimized nutrition to allow more effective adaptation and recovery from exercise. Resistance exercise is the most effective anabolic form of exercise, and over the past 20 years, the research base for resistance exercise has just started to develop to a significant volume of work to help in the decision-making process in program design (). The interface with nutritional strategies has been less

  6. Hypoxia-Independent Downregulation of Hypoxia-Inducible Factor 1 Targets by Androgen Deprivation Therapy in Prostate Cancer

    SciTech Connect

    Ragnum, Harald Bull; Røe, Kathrine; Holm, Ruth; Vlatkovic, Ljiljana; Nesland, Jahn Marthin; Aarnes, Eva-Katrine; Ree, Anne Hansen; Flatmark, Kjersti; Seierstad, Therese; Lilleby, Wolfgang; Lyng, Heidi

    2013-11-15

    Purpose: We explored changes in hypoxia-inducible factor 1 (HIF1) signaling during androgen deprivation therapy (ADT) of androgen-sensitive prostate cancer xenografts under conditions in which no significant change in immunostaining of the hypoxia marker pimonidazole had occurred. Methods and Materials: Gene expression profiles of volume-matched androgen-exposed and androgen-deprived CWR22 xenografts, with similar pimonidazole-positive fractions, were compared. Direct targets of androgen receptor (AR) and HIF1 transcription factors were identified among the differentially expressed genes by using published lists. Biological processes affected by ADT were determined by gene ontology analysis. HIF1α protein expression in xenografts and biopsy samples from 35 patients receiving neoadjuvant ADT was assessed by immunohistochemistry. Results: A total of 1344 genes showed more than 2-fold change in expression by ADT, including 35 downregulated and 5 upregulated HIF1 targets. Six genes were shared HIF1 and AR targets, and their downregulation was confirmed with quantitative RT-PCR. Significant suppression of the biological processes proliferation, metabolism, and stress response in androgen-deprived xenografts was found, consistent with tumor regression. Nineteen downregulated HIF1 targets were involved in those significant biological processes, most of them in metabolism. Four of these were shared AR and HIF1 targets, including genes encoding the regulatory glycolytic proteins HK2, PFKFB3, and SLC2A1. Most of the downregulated HIF1 targets were induced by hypoxia in androgen-responsive prostate cancer cell lines, confirming their role as hypoxia-responsive HIF1 targets in prostate cancer. Downregulation of HIF1 targets was consistent with the absence of HIF1α protein in xenografts and downregulation in patients by ADT (P<.001). Conclusions: AR repression by ADT may lead to downregulation of HIF1 signaling independently of hypoxic fraction, and this may contribute to

  7. Disorders of sex development expose transcriptional autonomy of genetic sex and androgen-programmed hormonal sex in human blood leukocytes

    PubMed Central

    Holterhus, Paul-Martin; Bebermeier, Jan-Hendrik; Werner, Ralf; Demeter, Janos; Richter-Unruh, Annette; Cario, Gunnar; Appari, Mahesh; Siebert, Reiner; Riepe, Felix; Brooks, James D; Hiort, Olaf

    2009-01-01

    Background Gender appears to be determined by independent programs controlled by the sex-chromosomes and by androgen-dependent programming during embryonic development. To enable experimental dissection of these components in the human, we performed genome-wide profiling of the transcriptomes of peripheral blood mononuclear cells (PBMC) in patients with rare defined "disorders of sex development" (DSD, e.g., 46, XY-females due to defective androgen biosynthesis) compared to normal 46, XY-males and 46, XX-females. Results A discrete set of transcripts was directly correlated with XY or XX genotypes in all individuals independent of male or female phenotype of the external genitalia. However, a significantly larger gene set in the PBMC only reflected the degree of external genital masculinization independent of the sex chromosomes and independent of concurrent post-natal sex steroid hormone levels. Consequently, the architecture of the transcriptional PBMC-"sexes" was either male, female or even "intersex" with a discordant alignment of the DSD individuals' genetic and hormonal sex signatures. Conclusion A significant fraction of gene expression differences between males and females in the human appears to have its roots in early embryogenesis and is not only caused by sex chromosomes but also by long-term sex-specific hormonal programming due to presence or absence of androgen during the time of external genital masculinization. Genetic sex and the androgen milieu during embryonic development might therefore independently modulate functional traits, phenotype and diseases associated with male or female gender as well as with DSD conditions. PMID:19570224

  8. Id-1 expression induces androgen-independent prostate cancer cell growth through activation of epidermal growth factor receptor (EGF-R).

    PubMed

    Ling, Ming-Tat; Wang, Xianghong; Lee, Davy T; Tam, P C; Tsao, Sai-Wah; Wong, Yong-Chuan

    2004-04-01

    The failure of prostate cancer treatment is largely due to the development of androgen independence, since the androgen depletion therapy remains the front-line option for this cancer. Previously, we reported that over-expression of the helix-loop-helix protein Id-1 was associated with progression of prostate cancer and ectopic expression of Id-1 induced serum-independent proliferation in prostate cancer cells. In the present study, we investigated if exogenous Id-1 expression in the androgen sensitive LNCaP cells had any effect on androgen-dependent cell growth and studied the molecular mechanisms involved. Using stable Id-1 transfectants, we found that expression of Id-1 was able to reduce androgen-stimulated growth and S phase fraction of the cell cycle in LNCaP cells, indicating that Id-1 may be involved in the development of androgen independence in these cells. The Id-1-induced androgen-independent prostate cancer cell growth was correlated with up-regulation of EGF-R (epidermal growth factor-receptor) and PSA (prostate specific antigen) expression, as confirmed by western blotting analysis and luciferase assays. In contrast, down-regulation of Id-1 in androgen-independent DU145 cells by its antisense oligonucleotides resulted in suppression of EGF-R expression at both transcriptional and protein levels. In addition, the results from immunohistochemistry study showed that Id-1 expression was significantly elevated in hormone refractory prostate cancer tissues when compared with the hormone-dependent tumours. Our results suggest that up-regulation of Id-1 in prostate cancer cells may be one of the mechanisms responsible for developing androgen independence and this process may be regulated through induction of EGF-R expression. Inactivation of Id-1 may provide a potential therapeutic strategy leading to inhibition of androgen-independent prostate cancer cell growth.

  9. Androgen receptor–negative human prostate cancer cells induce osteogenesis in mice through FGF9-mediated mechanisms

    PubMed Central

    Li, Zhi Gang; Mathew, Paul; Yang, Jun; Starbuck, Michael W.; Zurita, Amado J.; Liu, Jie; Sikes, Charles; Multani, Asha S.; Efstathiou, Eleni; Lopez, Adriana; Wang, Jing; Fanning, Tina V.; Prieto, Victor G.; Kundra, Vikas; Vazquez, Elba S.; Troncoso, Patricia; Raymond, Austin K.; Logothetis, Christopher J.; Lin, Sue-Hwa; Maity, Sankar; Navone, Nora M.

    2008-01-01

    In prostate cancer, androgen blockade strategies are commonly used to treat osteoblastic bone metastases. However, responses to these therapies are typically brief, and the mechanism underlying androgen-independent progression is not clear. Here, we established what we believe to be the first human androgen receptor–negative prostate cancer xenografts whose cells induced an osteoblastic reaction in bone and in the subcutis of immunodeficient mice. Accordingly, these cells grew in castrated as well as intact male mice. We identified FGF9 as being overexpressed in the xenografts relative to other bone-derived prostate cancer cells and discovered that FGF9 induced osteoblast proliferation and new bone formation in a bone organ assay. Mice treated with FGF9-neutralizing antibody developed smaller bone tumors and reduced bone formation. Finally, we found positive FGF9 immunostaining in prostate cancer cells in 24 of 56 primary tumors derived from human organ-confined prostate cancer and in 25 of 25 bone metastasis cases studied. Collectively, these results suggest that FGF9 contributes to prostate cancer–induced new bone formation and may participate in the osteoblastic progression of prostate cancer in bone. Androgen receptor–null cells may contribute to the castration-resistant osteoblastic progression of prostate cancer cells in bone and provide a preclinical model for studying therapies that target these cells. PMID:18618013

  10. Androgen receptor-negative human prostate cancer cells induce osteogenesis in mice through FGF9-mediated mechanisms.

    PubMed

    Li, Zhi Gang; Mathew, Paul; Yang, Jun; Starbuck, Michael W; Zurita, Amado J; Liu, Jie; Sikes, Charles; Multani, Asha S; Efstathiou, Eleni; Lopez, Adriana; Wang, Jing; Fanning, Tina V; Prieto, Victor G; Kundra, Vikas; Vazquez, Elba S; Troncoso, Patricia; Raymond, Austin K; Logothetis, Christopher J; Lin, Sue-Hwa; Maity, Sankar; Navone, Nora M

    2008-08-01

    In prostate cancer, androgen blockade strategies are commonly used to treat osteoblastic bone metastases. However, responses to these therapies are typically brief, and the mechanism underlying androgen-independent progression is not clear. Here, we established what we believe to be the first human androgen receptor-negative prostate cancer xenografts whose cells induced an osteoblastic reaction in bone and in the subcutis of immunodeficient mice. Accordingly, these cells grew in castrated as well as intact male mice. We identified FGF9 as being overexpressed in the xenografts relative to other bone-derived prostate cancer cells and discovered that FGF9 induced osteoblast proliferation and new bone formation in a bone organ assay. Mice treated with FGF9-neutralizing antibody developed smaller bone tumors and reduced bone formation. Finally, we found positive FGF9 immunostaining in prostate cancer cells in 24 of 56 primary tumors derived from human organ-confined prostate cancer and in 25 of 25 bone metastasis cases studied. Collectively, these results suggest that FGF9 contributes to prostate cancer-induced new bone formation and may participate in the osteoblastic progression of prostate cancer in bone. Androgen receptor-null cells may contribute to the castration-resistant osteoblastic progression of prostate cancer cells in bone and provide a preclinical model for studying therapies that target these cells. PMID:18618013

  11. Immunocytochemical detection of androgen receptor in human temporal cortex characterization and application of polyclonal androgen receptor antibodies in frozen and paraffin-embedded tissues.

    PubMed

    Puy, L; MacLusky, N J; Becker, L; Karsan, N; Trachtenberg, J; Brown, T J

    1995-11-01

    Immunocytochemical and biochemical studies have demonstrated the presence of androgen receptor protein in various regions of the rodent and non-human primate cortex. Localization of androgen receptor in the human brain has, however, not been studied as extensively, because of difficulties in obtaining suitable tissue samples. In the present study, we have localized androgen receptors in both frozen and paraffin-embedded temporal cortex from epileptic patients undergoing resection. Polyclonal antibodies were raised against fusion proteins containing fragments of the human androgen receptor protein. The antibodies were affinity-purified against the corresponding fusion protein. Immunoprecipitation and Western blotting using extracts from human cell lines demonstrated the specificity of the antibodies for the human androgen receptor and lack of cross-reactivity with other steroid hormone receptors. Immunocytochemistry was performed on frozen and paraffin sections of human temporal cortex and in paraffin-embedded benign hyperplastic prostates (BPH), as well as prostate and breast carcinomas, by the streptavidin-biotin-peroxidase method. Antigen-retrieval was performed in paraffin-embedded sections using microwave irradiation. Specific nuclear and cytoplasmic immunoreactivity for androgen receptor was detected in neurons, astrocytes, oligodendrocytes, and microglia cells of the temporal cortex. In contrast, only nuclear staining was observed in BPH, prostate and breast carcinomas. Immunoprecipitation of human temporal cortex lysate and subsequent Western blot analysis demonstrated the expression of a 98 kDa immunoreactive protein, slightly smaller than the reported molecular weight of the wild-type androgen receptor. These results provide further evidence for the expression of androgen receptor in the human temporal cortex. The use of these immunocytochemical techniques should enable the retrospective determination of possible changes in androgen receptor expression in

  12. Aspirin inhibits androgen response to chorionic gonadotropin in humans.

    PubMed

    Conte, D; Romanelli, F; Fillo, S; Guidetti, L; Isidori, A; Franceschi, F; Latini, M; di Luigi, L

    1999-12-01

    Eicosanoids play an important role in the regulation of the hypothalamic-pituitary axis; less clear is their role in testicular steroidogenesis. To evaluate the involvement of cyclooxygenase metabolites, such as prostaglandins, in the regulation of human testicular steroidogenesis, we examined the effects of a prostaglandin-blocker, aspirin, on plasma testosterone, pregnenolone, progesterone, 17OH-progesterone, androstenedione, dehydroepiandrosterone, and 17beta-estradiol response to human chorionic gonadotropin (hCG) in normal male volunteers in a placebo-controlled, single-blinded study. To test the efficacy of aspirin, seminal prostaglandin E(2) levels were also determined. hCG stimulation increased peripheral levels of testosterone, 17OH-progesterone, androstenedione, dehydroepiandrosterone, and 17beta-estradiol, without affecting circulating pregnenolone and progesterone values. Aspirin significantly lowered seminal prostaglandin E(2) levels, whereas it did not modify steroid concentrations not exposed to exogenous hCG. Moreover, the drug significantly reduced the response of testosterone, 17OH-progesterone, androstenedione, and dehydroepiandrosterone to hCG, as assessed by the mean integrated area under the curve, whereas it did not influence 17beta-estradiol response. In conclusion, aspirin treatment inhibits androgen response to chorionic gonadotropin stimulation in normal humans. The action of aspirin is probably mediated via an effective arachidonate cyclooxygenase block.

  13. Androgen Regulated Genes in Human Prostate Xenografts in Mice: Relation to BPH and Prostate Cancer

    PubMed Central

    Love, Harold D.; Booton, S. Erin; Boone, Braden E.; Breyer, Joan P.; Koyama, Tatsuki; Revelo, Monica P.; Shappell, Scott B.; Smith, Jeffrey R.; Hayward, Simon W.

    2009-01-01

    Benign prostatic hyperplasia (BPH) and prostate carcinoma (CaP) are linked to aging and the presence of androgens, suggesting that androgen regulated genes play a major role in these common diseases. Androgen regulation of prostate growth and development depends on the presence of intact epithelial-stromal interactions. Further, the prostatic stroma is implicated in BPH. This suggests that epithelial cell lines are inadequate to identify androgen regulated genes that could contribute to BPH and CaP and which could serve as potential clinical biomarkers. In this study, we used a human prostate xenograft model to define a profile of genes regulated in vivo by androgens, with an emphasis on identifying candidate biomarkers. Benign transition zone (TZ) human prostate tissue from radical prostatectomies was grafted to the sub-renal capsule site of intact or castrated male immunodeficient mice, followed by the removal or addition of androgens, respectively. Microarray analysis of RNA from these tissues was used to identify genes that were; 1) highly expressed in prostate, 2) had significant expression changes in response to androgens, and, 3) encode extracellular proteins. A total of 95 genes meeting these criteria were selected for analysis and validation of expression in patient prostate tissues using quantitative real-time PCR. Expression levels of these genes were measured in pooled RNAs from human prostate tissues with varying severity of BPH pathologic changes and CaP of varying Gleason score. A number of androgen regulated genes were identified. Additionally, a subset of these genes were over-expressed in RNA from clinical BPH tissues, and the levels of many were found to correlate with disease status. Our results demonstrate the feasibility, and some of the problems, of using a mouse xenograft model to characterize the androgen regulated expression profiles of intact human prostate tissues. PMID:20027305

  14. Regulation of Sclerostin Production in Human Male Osteocytes by Androgens: Experimental and Clinical Evidence.

    PubMed

    Di Nisio, Andrea; De Toni, Luca; Speltra, Elena; Rocca, Maria Santa; Taglialavoro, Giuseppe; Ferlin, Alberto; Foresta, Carlo

    2015-12-01

    In this study we aimed to elucidate a possible role of T in the regulation of sclerostin, a glycoprotein secreted by osteocytes known to regulate bone mass. To this end, we evaluated the effect of T stimulation on sclerostin production and gene expression in human cultured osteocytes. In addition, we evaluated serum sclerostin levels in a cohort of 20 hypogonadal male patients, compared with 20 age-matched eugonadal controls. Stimulation with DHT decreased sclerostin expression in cultured osteocytes in a time- and dose-dependent manner. Confirming a direct androgen receptor-mediated effect on sclerostin production, flutamide coincubation and silencing of androgen receptor gene in osteocytes abolished the DHT effects. In addition, hypogonadal patients showed higher serum sclerostin levels with respect to controls (145.87 ± 50.83 pg/mL vs 84.02 ± 32.15 pg/mL; P < .001) and in both probands and controls, serum T levels were negatively correlated with sclerostin (R = -0.664, P = 0.007, and R = -0.447, P = .045, respectively). Finally, multiple stepwise regression analysis showed that T represented the only independent predictor of sclerostin levels. In conclusion, by showing a direct correlation between T and sclerostin, both in vivo and in vitro, this study adds further support to the emerging clinical and experimental studies focusing on sclerostin as a therapeutic target for osteoporosis treatment.

  15. Functional characterisation of a natural androgen receptor missense mutation (N771H) causing human androgen insensitivity syndrome.

    PubMed

    Cai, J; Cai, L-Q; Hong, Y; Zhu, Y-S

    2012-05-01

    Androgen insensitivity syndrome (AIS) is an X-linked disorder due to mutations of androgen receptor (AR) gene. Various AR mutations have been identified, and the characterisation of these mutations greatly facilitates our understanding of AR structure-function. In this study, we have analysed an AR missense mutation (N771H) identified in patients with AIS. Functional analysis of the mutant AR was performed by in vitro mutagenesis-cotransfection assays. Compared to the wild-type AR, the dose-response curve of dihydrotestosterone-induced transactivation activity in the mutant AR was greatly shifted to the right and significantly decreased. However, the maximal efficacy of transactivation activity in the mutant AR was similar to that of the wild type. Receptor binding assay indicated that the mutant AR had an approximately 2.5-fold lower binding affinity to dihydrotestosterone compared to the wild type. Western blot analysis showed that the size and the expression level of mutant AR in transfected cells were comparable to the wild type. These data underscore the importance of asparagine at amino acid position 771 of human AR in normal ligand binding and normal receptor function, and a mutation at this position results in androgen insensitivity in affected subjects.

  16. Androgen deprivation therapy sensitizes triple negative breast cancer cells to immune-mediated lysis through androgen receptor independent modulation of osteoprotegerin

    PubMed Central

    Gameiro, Sofia R.; Richards, Jacob; Hall, Ashley B.; Hodge, James W.

    2016-01-01

    Among breast cancer types, triple-negative breast cancer (TNBC) has the fewest treatment options and the lowest 5-year survival rate. Androgen receptor (AR) inhibition has displayed efficacy against breast cancer preclinically and is currently being examined clinically in AR positive TNBC patients. Androgen deprivation has been shown to induce immunogenic modulation; the alteration of tumor cell phenotype resulting in increased sensitivity to immune-mediated killing. We evaluated the ability of AR inhibition to reduce the growth and improve the immune-mediated killing of breast cancer cells with differing expression of the estrogen receptor and AR. While AR expression was required for the growth inhibitory effects of enzalutamide on breast cancer cells, both enzalutamide and abiraterone improved the sensitivity of breast cancer cells to immune-mediated lysis independent of detectable AR expression. This increase in sensitivity was linked to an increase in cell surface tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor expression as well as a significant reduction in the expression of osteoprotegerin (OPG). The reduction in OPG was further examined and found to be critical for the increase in sensitivity of AR- TNBC cells to immune-mediated killing. The data presented herein further support the use of AR inhibition therapy in the AR+ TNBC setting. These data, however, also support the consideration of AR inhibition therapy for the treatment of AR- TNBC, especially in combination with cancer immunotherapy, providing a potential novel therapeutic option for select patients. PMID:27015557

  17. Inhibition of constitutive aryl hydrocarbon receptor (AhR) signaling attenuates androgen independent signaling and growth in (C4-2) prostate cancer cells

    PubMed Central

    Tran, Cindy; Richmond, Oliver; Aaron, LaTayia; Powell, Joann B.

    2013-01-01

    The aryl hydrocarbon receptor is a member of the basic-helix-loop-helix family of transcription factors. AhR mediates the biochemical and toxic effects of a number of polyaromatic hydrocarbons such as 2,3,7,8,-tetrachloro-dibenzo-p-dioxin (TCDD). AhR is widely known for regulating the transcription of drug metabolizing enzymes involved in the xenobiotic metabolism of carcinogens and therapeutic agents, such as cytochrome P450-1B1 (CYP1B1). Additionally, AhR has also been reported to interact with multiple signaling pathways during prostate development. Here we investigate the effect of sustained AhR signaling on androgen receptor function in prostate cancer cells. Immunoblot analysis shows that AhR expression is increased in androgen independent (C4-2) prostate cancer cells when compared to androgen sensitive (LNCaP) cells. RT-PCR studies revealed constitutive AhR signaling in C4-2 cells without the ligand induced activation required in LNCaP cells. A reduction of AhR activity by short RNA mediated silencing in C4-2 cells reduced expression of both AhR and androgen responsive genes. The decrease in androgen responsive genes correlates to a decrease in phosphorylated androgen receptor and androgen receptor expression in the nucleus. Furthermore, the forced decrease in AhR expression resulted in a 50% decline in the growth rate of C4-2 cells. These data indicates that AhR is required to maintain hormone independent signaling and growth by the androgen receptor in C4-2 cells. Collectively, these data provide evidence of a direct role for AhR in androgen independent signaling and provides insight into the molecular mechanisms responsible for sustained androgen receptor signaling in hormone refractory prostate cancer. PMID:23266674

  18. Androgen responsiveness of the new human endometrial cancer cell line MFE-296.

    PubMed

    Hackenberg, R; Beck, S; Filmer, A; Hushmand Nia, A; Kunzmann, R; Koch, M; Slater, E P; Schulz, K D

    1994-04-01

    MFE-296 endometrial cancer cells express androgen receptors in vitro. These cells, which are tumorigenic in nude mice, are derived from a moderately differentiated human endometrial adenocarcinoma. They express vimentin and the cytokeratins 7, 8, 18, and 19. Karyotyping revealed near-tetraploidy for most of the cells. No marker chromosomes were observed. DNA analyses confirmed the genetic identity of the cell line and the patient from whom the cell line was derived. Proliferation of MFE-296 cells was inhibited by the progestin R5020 and the androgen dihydrotestosterone (DHT). The inhibition of proliferation by DHT was antagonized by the antiandrogen Casodex, demonstrating the involvement of the androgen receptor. Androgen binding was determined at 22,000 binding sites per cell using a whole-cell assay (KD = 0.05 nM) and 30 fmol/mg protein with the dextran charcoal method; 7 fmol/mg protein of progesterone receptors were found, whereas estrogen receptors were below 5 fmol/mg protein. The androgen receptor was functionally intact, as demonstrated by transfection experiments with a reporter-gene construct, containing an androgen-responsive element. In MFE-296 cells the content of the androgen receptor was up-regulated by its own ligand.

  19. Human androgen receptor expressed in HeLa cells activates transcription in vitro.

    PubMed Central

    De Vos, P; Schmitt, J; Verhoeven, G; Stunnenberg, H G

    1994-01-01

    The androgen receptor (AR) is a ligand-responsive transcription factor, belonging to the class of steroid receptors. AR mutations have been associated with various X-linked diseases, characterized by complete or partial resistance to androgens. To further analyse the molecular mechanism of action of the AR, we have produced the human AR in HeLa cells with a Vaccinia virus expression system. Binding studies on infected HeLa cells demonstrate that the recombinant AR interacts specifically and with high affinity with natural and synthetic androgens. In a gel retardation assay the partially purified AR specifically recognizes an androgen response element of the rat prostatic binding protein gene. Moreover, the recombinant AR activates transcription in vitro from a synthetic promoter construct containing glucocorticoid response elements (GRE). Images PMID:8165128

  20. The use of human skin fibroblasts to obtain potency estimates of drug binding to androgen receptors.

    PubMed

    Eil, C; Edelson, S K

    1984-07-01

    Although several drugs with antiandrogenic properties have been used to treat such conditions as prostatic carcinoma, precocious puberty, acne, and hirsutism, their relative strengths in human tissues are not known. Most of the compounds that are effective clinically in opposing androgen action interact with the androgen receptor in various assay systems. To determine in human cells the relative potencies of these agents as well as others with androgenic properties, we measured the abilities of various compounds to compete with [3H]dihydrotestosterone [( 3H]DHT) for androgen-binding sites in dispersed human genital skin fibroblasts at 22 degrees C. The concentrations of unlabeled DHT, methyltrienolone (a synthetic non- metabolizeable androgen), and testosterone required for 50% inhibition of [3H]DHT binding were similar, approximately 1 nM [0.87 +/- 0.12 (+/- SE), 1.18 +/- 0.18, and 1.01 +/- 0.20 nM, respectively]. The relative binding activities, defined by the ratio of the concentration of methyltrienolone to the concentration of competitor required for 50% displacement of [3H]DHT, were as follows: spironolactone greater than R2956 (a synthetic antiandrogen) greater than megestrol acetate greater than cyproterone acetate greater than estradiol greater than flutamide much greater than testolactone greater than cimetidine. Danazol, an androgen agonist that causes hirsutism, was nearly as effective as spironolactone in its ability to compete for the fibroblast androgen receptor, 50% inhibition of fibroblast [3H]DHT binding was achieved by 1.76 +/- 0.31 nM spironolactone and 2.85 +/- 0.50 nM danazol. Two other compounds that induce hirsutism, diphenylhydantoin and diazoxide, did not displace [3H]DHT. We conclude that 1) of the compounds tested, spironolactone, which is rapidly metabolized in vivo to a much less potent competitor, is the most potent antiandrogen in its ability to interact in vitro with human skin fibroblast androgen receptors; 2) estradiol is a

  1. Silibinin inhibits aberrant lipid metabolism, proliferation and emergence of androgen-independence in prostate cancer cells via primarily targeting the sterol response element binding protein 1

    PubMed Central

    Nambiar, Dhanya K.; Deep, Gagan; Singh, Rana P.; Agarwal, Chapla; Agarwal, Rajesh

    2014-01-01

    Prostate cancer (PCA) kills thousands of men every year, demanding additional approaches to better understand and target this malignancy. Recently, critical role of aberrant lipogenesis is highlighted in prostate carcinogenesis, offering a unique opportunity to target it to reduce PCA. Here, we evaluated efficacy and associated mechanisms of silibinin in inhibiting lipid metabolism in PCA cells. At physiologically achievable levels in human, silibinin strongly reduced lipid and cholesterol accumulation specifically in human PCA cells but not in non-neoplastic prostate epithelial PWR-1E cells. Silibinin also decreased nuclear protein levels of sterol regulatory element binding protein 1 and 2 (SREBP1/2) and their target genes only in PCA cells. Mechanistically, silibinin activated AMPK, thereby increasing SREBP1 phosphorylation and inhibiting its nuclear translocation; AMPK inhibition reversed silibinin-mediated decrease in nuclear SREBP1 and lipid accumulation. Additionally, specific SREBP inhibitor fatostatin and stable overexpression of SREBP1 further confirmed the central role of SREBP1 in silibinin-mediated inhibition of PCA cell proliferation and lipid accumulation and cell cycle arrest. Importantly, silibinin also inhibited synthetic androgen R1881-induced lipid accumulation and completely abrogated the development of androgen-independent LNCaP cell clones via targeting SREBP1/2. Together, these mechanistic studies suggest that silibinin would be effective against PCA by targeting critical aberrant lipogenesis. PMID:25294820

  2. Intracrine Androgens Enhance Decidualization and Modulate Expression of Human Endometrial Receptivity Genes.

    PubMed

    Gibson, Douglas A; Simitsidellis, Ioannis; Cousins, Fiona L; Critchley, Hilary O D; Saunders, Philippa T K

    2016-01-01

    The endometrium is a complex, steroid-dependent tissue that undergoes dynamic cyclical remodelling. Transformation of stromal fibroblasts (ESC) into specialised secretory cells (decidualization) is fundamental to the establishment of a receptive endometrial microenvironment which can support and maintain pregnancy. Androgen receptors (AR) are present in ESC; in other tissues local metabolism of ovarian and adrenal-derived androgens regulate AR-dependent gene expression. We hypothesised that altered expression/activity of androgen biosynthetic enzymes would regulate tissue availability of bioactive androgens and the process of decidualization. Primary human ESC were treated in vitro for 1-8 days with progesterone and cAMP (decidualized) in the presence or absence of the AR antagonist flutamide. Time and treatment-dependent changes in genes essential for a) intra-tissue biosynthesis of androgens (5α-reductase/SRD5A1, aldo-keto reductase family 1 member C3/AKR1C3), b) establishment of endometrial decidualization (IGFBP1, prolactin) and c) endometrial receptivity (SPP1, MAOA, EDNRB) were measured. Decidualization of ESC resulted in significant time-dependent changes in expression of AKR1C3 and SRD5A1 and secretion of T/DHT. Addition of flutamide significantly reduced secretion of IGFBP1 and prolactin and altered the expression of endometrial receptivity markers. Intracrine biosynthesis of endometrial androgens during decidualization may play a key role in endometrial receptivity and offer a novel target for fertility treatment. PMID:26817618

  3. Omega-3 fatty acid inhibition of prostate cancer progression to hormone independence is associated with suppression of mTOR signaling and androgen receptor expression.

    PubMed

    Friedrichs, William; Ruparel, Shivani B; Marciniak, Robert A; deGraffenried, Linda

    2011-01-01

    Currently, progression of prostate cancer to androgen independence remains the primary obstacle to improved survival. In order to improve overall survival, novel treatment strategies that are based upon specific molecular mechanisms that prolong the androgen-dependent state and that are useful for androgen-independent disease need to be identified. Both epidemiological as well as preclinical data suggest that omega-3 fatty acids are effective primary tumor prevention agents; however, their efficacy at preventing and treating refractory prostate cancer has not been as thoroughly investigated. We used an in vitro model of androgen ablation to determine the effect of treatment with omega-3 fatty acids on the progression to an androgen-independent state. The omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were able to prevent progression of LNCaP cells while the omega-6 fatty acid arachidonic acid (AA) actually promoted cell growth under conditions of hormone depletion. These results correlated with a decrease in the expression of the androgen receptor as well as suppression of the Akt/mTOR signaling pathway. Connecting the mechanisms by which omega-3 fatty acids affect phenotypic outcome is important for effective exploitation of these nutrient agents as a therapeutic approach. Understanding these processes is critical for the development of effective dietary intervention strategies that improve overall survival.

  4. Gonadotropin-Activated Androgen-Dependent and Independent Pathways Regulate Aquaporin Expression during Teleost (Sparus aurata) Spermatogenesis

    PubMed Central

    Zapater, Cinta; Cerdà, Joan

    2015-01-01

    The mediation of fluid homeostasis by multiple classes of aquaporins has been suggested to be essential during spermatogenesis and spermiation. In the marine teleost gilthead seabream (Sparus aurata), seven distinct aquaporins, Aqp0a, -1aa, -1ab, -7, -8b, -9b and -10b, are differentially expressed in the somatic and germ cell lineages of the spermiating testis, but the endocrine regulation of these channels during germ cell development is unknown. In this study, we investigated the in vivo developmental expression of aquaporins in the seabream testis together with plasma androgen concentrations. We then examined the in vitro regulatory effects of recombinant piscine gonadotropins, follicle-stimulating (rFsh) and luteinizing (rLh) hormones, and sex steroids on aquaporin mRNA levels during the spermatogenic cycle. During the resting phase, when plasma levels of androgens were low, the testis exclusively contained proliferating spermatogonia expressing Aqp1ab, whereas Aqp10b and -9b were localized in Sertoli and Leydig cells, respectively. At the onset of spermatogenesis and during spermiation, the increase of androgen plasma levels correlated with the additional appearance of Aqp0a and -7 in Sertoli cells, Aqp0a in spermatogonia and spermatocytes, Aqp1ab, -7 and -10b from spermatogonia to spermatozoa, and Aqp1aa and -8b in spermatids and spermatozoa. Short-term in vitro incubation of testis explants indicated that most aquaporins in Sertoli cells and early germ cells were upregulated by rFsh and/or rLh through androgen-dependent pathways, although Aqp1ab in proliferating spermatogonia was also activated by estrogens. However, expression of Aqp9b in Leydig cells, and of Aqp1aa and -7 in spermatocytes and spermatids, was also directly stimulated by rLh. These results reveal a complex gonadotropic control of aquaporin expression during seabream germ cell development, apparently involving both androgen-dependent and independent pathways, which may assure the fine tuning

  5. Castration induces up-regulation of intratumoral androgen biosynthesis and androgen receptor expression in an orthotopic VCaP human prostate cancer xenograft model.

    PubMed

    Knuuttila, Matias; Yatkin, Emrah; Kallio, Jenny; Savolainen, Saija; Laajala, Teemu D; Aittokallio, Tero; Oksala, Riikka; Häkkinen, Merja; Keski-Rahkonen, Pekka; Auriola, Seppo; Poutanen, Matti; Mäkelä, Sari

    2014-08-01

    Androgens are key factors involved in the development and progression of prostate cancer (PCa), and PCa growth can be suppressed by androgen deprivation therapy. In a considerable proportion of men receiving androgen deprivation therapy, however, PCa progresses to castration-resistant PCa (CRPC), making the development of efficient therapies challenging. We used an orthotopic VCaP human PCa xenograft model to study cellular and molecular changes in tumors after androgen deprivation therapy (castration). Tumor growth was monitored through weekly serum prostate-specific antigen measurements, and mice with recurrent tumors after castration were randomized to treatment groups. Serum prostate-specific antigen concentrations showed significant correlation with tumor volume. Castration-resistant tumors retained concentrations of intratumoral androgen (androstenedione, testosterone, and 5α-dihydrotestosterone) at levels similar to tumors growing in intact hosts. Accordingly, castration induced up-regulation of enzymes involved in androgen synthesis (CYP17A1, AKR1C3, and HSD17B6), as well as expression of full-length androgen receptor (AR) and AR splice variants (AR-V1 and AR-V7). Furthermore, AR target gene expression was maintained in castration-resistant xenografts. The AR antagonists enzalutamide (MDV3100) and ARN-509 suppressed PSA production of castration-resistant tumors, confirming the androgen dependency of these tumors. Taken together, the findings demonstrate that our VCaP xenograft model exhibits the key characteristics of clinical CRPC and thus provides a valuable tool for identifying druggable targets and for testing therapeutic strategies targeting AR signaling in CRPC.

  6. 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

  7. Small molecule screening reveals a transcription-independent pro-survival function of androgen receptor in castration-resistant prostate cancer.

    PubMed

    Narizhneva, Natalia V; Tararova, Natalia D; Ryabokon, Petro; Shyshynova, Inna; Prokvolit, Anatoly; Komarov, Pavel G; Purmal, Andrei A; Gudkov, Andrei V; Gurova, Katerina V

    2009-12-15

    In prostate cancer (PCa) patients, initial responsiveness to androgen deprivation therapy is frequently followed by relapse due to development of treatment-resistant androgen-independent PCa. This is typically associated with acquisition of mutations in AR that allow activity as a transcription factor in the absence of ligand, indicating that androgen-independent PCa remains dependent on AR function. Our strategy to effectively target AR in androgen-independent PCa involved using a cell-based readout to isolate small molecules that inhibit AR transactivation function through mechanisms other than modulation of ligand binding. A number of the identified inhibitors were toxic to AR-expressing PCa cells regardless of their androgen dependence. Among these, some only suppressed PCa cell growth (ARTIS), while others induced cell death (ARTIK). ARTIK, but not ARTIS, compounds caused disappearance of AR protein from treated cells. siRNA against AR behaved like ARTIK compounds, while a dominant negative AR mutant that prevents AR-mediated transactivation but does not eliminate the protein showed only a growth suppressive effect. These observations reveal a transcription-independent function of AR that is essential for PCa cell viability and, therefore, is an ideal target for anti-PCa treatment. Indeed, several of the identified AR inhibitors demonstrated in vivo efficacy in mouse models of PCa and are candidates for pharmacologic optimization.

  8. Cumulative effects of anti-androgenic chemical mixtures and their relevance to human health risk assessment

    EPA Science Inventory

    Kembra L. Howdeshell and L. Earl Gray, Jr.Toxicological studies of defined chemical mixtures assist human health risk assessment by characterizing the joint action of chemicals. This presentation will review the effects of anti-androgenic chemical mixtures on reproductive tract d...

  9. Analytical methodology for the profiling and characterization of androgen receptor active compounds in human placenta.

    PubMed

    Indiveri, Paolo; Horwood, Julia; Abdul-Sada, Alaa; Arrebola, Juan P; Olea, Nicolas; Hill, Elizabeth M

    2014-08-01

    The exposure to endocrine disrupting chemicals during foetal development has been proposed to cause reproductive dysfunctions in the neonate or later life. In order to support such studies, an analytical method was developed to profile the receptor mediated (anti)androgenic activities present in extracts of placenta samples. Placenta samples from women giving birth to healthy male neonates were extracted and fractionated by HPLC. Fractions containing androgen receptor (AR) activity were detected using an in vitro yeast-based human androgen receptor transcription screen. GC-MS analyses of receptor active fractions resulted in detection of chemical contaminants including antimicrobial and cosmetic compounds which exhibited AR antagonist activity in the yeast screen, and endogenously derived steroids which contributed to both the agonist and antagonistic activity in the samples. The bioassay-directed fractionation methodology developed in this study revealed the potential to identify mixtures of chemical contaminants that should be investigated for potential effects on the reproductive system.

  10. Androgen receptor (AR) suppresses miRNA-145 to promote renal cell carcinoma (RCC) progression independent of VHL status

    PubMed Central

    Chen, Yuan; Sun, Yin; Rao, Qun; Xu, Hua; Li, Lei; Chang, Chawnshang

    2015-01-01

    Mutational inactivation of the VHL tumor suppressor plays key roles in the development of renal cell carcinoma (RCC), and mutated VHL-mediated VEGF induction has become the main target for the current RCC therapy. Here we identified a signal pathway of VEGF induction by androgen receptor (AR)/miRNA-145 as a new target to suppress RCC progression. Mechanism dissection revealed that AR might function through binding to the androgen receptor element (ARE) located on the promoter region of miRNA-145 to suppress p53's ability to induce expression of miRNA-145 that normally suppresses expression of HIF2α/VEGF/MMP9/CCND1. Suppressing AR with AR-shRNA or introducing exogenous miRNA-145 mimic can attenuate RCC progression independent of VHL status. MiR-145 mimic in preclinical RCC orthotopic xenograft mouse model revealed its efficacy in suppression of RCC progression. These results together identified signals by AR-suppressed miRNA-145 as a key player in the RCC progression via regulating HIF2α/VEGF/MMP9/CCND1 expression levels. Blockade of the newly identified signal by AR inhibition or miRNA-145 mimics has promising therapeutic benefit to suppress RCC progression. PMID:26304926

  11. 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 ...

  12. Antagonists of growth hormone-releasing hormone inhibit growth of androgen-independent prostate cancer through inactivation of ERK and Akt kinases.

    PubMed

    Rick, Ferenc G; Schally, Andrew V; Szalontay, Luca; Block, Norman L; Szepeshazi, Karoly; Nadji, Mehrdad; Zarandi, Marta; Hohla, Florian; Buchholz, Stefan; Seitz, Stephan

    2012-01-31

    The management of castration-resistant prostate cancer (CRPC) presents a clinical challenge because of limitations in efficacy of current therapies. Novel therapeutic strategies for the treatment of CRPC are needed. Antagonists of hypothalamic growth hormone-releasing hormone (GHRH) inhibit growth of various malignancies, including androgen-dependent and independent prostate cancer, by suppressing diverse tumoral growth factors, especially GHRH itself, which acts as a potent autocrine/paracrine growth factor in many tumors. We evaluated the effects of the GHRH antagonist, JMR-132, on PC-3 human androgen-independent prostate cancer cells in vitro and in vivo. JMR-132 suppressed the proliferation of PC-3 cells in vitro in a dose-dependent manner and significantly inhibited growth of PC-3 tumors by 61% (P < 0.05). The expression of GHRH, GHRH receptors, and their main splice variant, SV1, in PC-3 cells and tumor xenografts was demonstrated by RT-PCR and Western blot. The content of GHRH protein in PC-3 xenografts was lowered markedly, by 66.3% (P < 0.01), after treatment with JMR-132. GHRH induced a significant increase in levels of ERK, but JMR-132 abolished this outcome. Our findings indicate that inhibition of PC-3 prostate cancer by JMR-132 involves inactivation of Akt and ERK. The inhibitory effect produced by GHRH antagonist can result in part from inactivation of the PI3K/Akt/mammalian target of rapamycin and Raf/MEK/ERK pathways and from the reduction in GHRH produced by cancer cells. Our findings support the role of GHRH as an autocrine growth factor in prostate cancer and suggest that antagonists of GHRH should be considered for further development as therapy for CRPC.

  13. Crystallization and preliminary X-ray analysis of the human androgen receptor ligand-binding domain with a coactivator-like peptide and selective androgen receptor modulators.

    PubMed

    Thauvin, Maxime; Robin-Jagerschmidt, Catherine; Nique, François; Mollat, Patrick; Fleury, Damien; Prangé, Thierry

    2008-12-01

    The ligand-binding domain of the human androgen receptor has been cloned, overproduced and crystallized in the presence of a coactivator-like 11-mer peptide and two different nonsteroidal ligands. The crystals of the two ternary complexes were isomorphous and belonged to space group P2(1)2(1)2(1), with one molecule in the asymmetric unit. They diffracted to 1.7 and 1.95 A resolution, respectively. Structure determination of these two complexes will help in understanding the mode of binding of selective nonsteroidal androgens versus endogenous steroidal ligands and possibly the origin of their tissue selectivity.

  14. Secretion of Unconjugated Androgens and Estrogens by the Normal and Abnormal Human Testis before and after Human Chorionic Gonadotropin

    PubMed Central

    Weinstein, R. L.; Kelch, R. P.; Jenner, M. R.; Kaplan, S. L.; Grumbach, M. M.

    1974-01-01

    The secretion of androgens and estrogens by normal and abnormal testes was compared by determining the concentrations of dehydroepiandrosterone (DHEA), androstenedione (Δ4A), testosterone (T), estrone (E1), and 17β-estradiol (E2) in peripheral and spermatic venous plasma samples from 14 normal men and 5 men with unilateral testicular atrophy. Four normal men and one patient with unilateral atrophy of the testis were given human chorionic gonadotropin (HCG) before surgery. Plasma estrogens were determined by radioimmunoassay; plasma androgens were measured by the double-isotope dilution derivative technique. Peripheral concentrations of these steroids before and after HCG were similar in both the normal men and the patients with unilateral testicular atrophy. In normal men, the mean ±SE spermatic venous concentrations were DHEA, 73.1±11.7 ng/ml; Δ4A, 30.7±7.9 ng/ml; T, 751±114 ng/ml; E1, 306±55 pg/ml; and E2, 1298±216 pg/ml. Three of four subjects with unilateral testicular atrophy had greatly diminished spermatic venous levels of androgens and estrogens. HCG treatment increased the testicular secretion of DHEA and T fivefold, Δ4A threefold, E1 sixfold, and E2 eightfold in normal men. In the single subject with an atrophic testis who received HCG, the spermatic venous concentrations of androgens and estrogens were much less than in normal men similarly treated. We conclude that: (a) E1 is secreted by the human testis, but testicular secretion of E1 accounts for less than 5% of E1 production in normal men; (b) HCG stimulation produces increases in spermatic venous estrogens equal to or greater than the changes in androgens, including testosterone; and (c) strikingly decreased secretion of androgen and estrogen by unilateral atrophic human tests cannot be appreciated by analyses of peripheral steroid concentrations. PMID:4271572

  15. Caveolae Contribute to the Apoptosis Resistance Induced by the α1A-Adrenoceptor in Androgen-Independent Prostate Cancer Cells

    PubMed Central

    Katsogiannou, Maria; Boustany, Charbel El; Gackiere, Florian; Delcourt, Philippe; Athias, Anne; Mariot, Pascal; Dewailly, Etienne; Jouy, Nathalie; Lamaze, Christophe; Bidaux, Gabriel; Mauroy, Brigitte; Prevarskaya, Natalia; Slomianny, Christian

    2009-01-01

    Background During androgen ablation prostate cancer cells' growth and survival become independent of normal regulatory mechanisms. These androgen-independent cells acquire the remarkable ability to adapt to the surrounding microenvironment whose factors, such as neurotransmitters, influence their survival. Although findings are becoming evident about the expression of α1A-adrenoceptors in prostate cancer epithelial cells, their exact functional role in androgen-independent cells has yet to be established. Previous work has demonstrated that membrane lipid rafts associated with key signalling proteins mediate growth and survival signalling pathways in prostate cancer cells. Methodology/Principal Findings In order to analyze the membrane topology of the α1A-adrenoceptor we explored its presence by a biochemical approach in purified detergent resistant membrane fractions of the androgen-independent prostate cancer cell line DU145. Electron microscopy observations demonstrated the colocalisation of the α1A-adrenoceptor with caveolin-1, the major protein component of caveolae. In addition, we showed that agonist stimulation of the α1A-adrenoceptor induced resistance to thapsigargin-induced apoptosis and that caveolin-1 was necessary for this process. Further, immunohistofluorescence revealed the relation between high levels of α1A-adrenoceptor and caveolin-1 expression with advanced stage prostate cancer. We also show by immunoblotting that the TG-induced apoptosis resistance described in DU145 cells is mediated by extracellular signal-regulated kinases (ERK). Conclusions/Significance In conclusion, we propose that α1A-adrenoceptor stimulation in androgen-independent prostate cancer cells via caveolae constitutes one of the mechanisms contributing to their protection from TG-induced apoptosis. PMID:19763272

  16. LINE-1 ORF-1p functions as a novel androgen receptor co-activator and promotes the growth of human prostatic carcinoma cells.

    PubMed

    Lu, Yinying; Feng, Fan; Yang, Yutao; Gao, Xudong; Cui, Jiajun; Zhang, Chuanfu; Zhang, Fan; Xu, Zhongxian; Qv, Jianhui; Wang, Chunping; Zeng, Zhen; Zhu, Yunfeng; Yang, Yongping

    2013-02-01

    Widespread interest in the mechanism of transcriptional regulation by the androgen receptor (AR) has been stimulated by the finding that AR signaling is critically important in the progression of human prostate cancers. Co-factors, the co-repressors, or the co-activators are responsible for the regulation of AR activation. The pro-oncogene human Long Interspersed Nucleotide acid Element-1 (LINE-1) encodes LINE-1 ORF-1p and plays important roles in the development and progression of several human carcinomas. In this study, the results showed that LINE-1 ORF-1p increased the AR transcriptional activity and in turn enhanced the expression of prostate specific antigen (PSA) in the presence of R1881. A physical protein-protein interaction between the AR signaling and the LINE-1 ORF-1p was identified by the immunoprecipitation assays and GST pull-down assays. Furthermore, LINE-1 ORF-1p would function as a novel AR positive co-regulator through modulating its cytoplasm/nucleus translocation and the recruitment to the androgen response element in the PSA gene promoter. Our date also showed that the LINE-1 ORF-1p promoted the proliferation and anchor-independent growth of LNCaP (ligand dependent) and PC-3 (ligand independent) human prostatic carcinoma cells. By investigating a novel role of the LINE-1 ORF-1p in the androgen/androgen receptor signaling pathway regulation, our study identifies that LINE-1 ORF-1p may be a novel AR co-regulator and molecular target for human prostate carcinoma therapy.

  17. Retinoic acid receptor beta and angiopoietin-like protein 1 are involved in the regulation of human androgen biosynthesis

    PubMed Central

    Udhane, Sameer S.; Pandey, Amit V.; Hofer, Gaby; Mullis, Primus E.; Flück, Christa E.

    2015-01-01

    Androgens are essential for sexual development and reproduction. However, androgen regulation in health and disease is poorly understood. We showed that human adrenocortical H295R cells grown under starvation conditions acquire a hyperandrogenic steroid profile with changes in steroid metabolizing enzymes HSD3B2 and CYP17A1 essential for androgen production. Here we studied the regulatory mechanisms underlying androgen production in starved H295R cells. Microarray expression profiling of normal versus starved H295R cells revealed fourteen differentially expressed genes; HSD3B2, HSD3B1, CYP21A2, RARB, ASS1, CFI, ASCL1 and ENC1 play a role in steroid and energy metabolism and ANGPTL1, PLK2, DUSP6, DUSP10 and FREM2 are involved in signal transduction. We discovered two new gene networks around RARB and ANGPTL1, and show how they regulate androgen biosynthesis. Transcription factor RARB stimulated the promoters of genes involved in androgen production (StAR, CYP17A1 and HSD3B2) and enhanced androstenedione production. For HSD3B2 regulation RARB worked in cooperation with Nur77. Secretory protein ANGPTL1 modulated CYP17A1 and DUSP6 expression by inducing ERK1/2 phosphorylation. By contrast, our studies revealed no evidence for hormones or cell cycle involvement in regulating androgen biosynthesis. In summary, these studies establish a firm role for RARB and ANGPTL1 in the regulation of androgen production in H295R cells. PMID:25970467

  18. Synthesis of 17β-N-arylcarbamoylandrost-4-en-3-one derivatives and their anti-proliferative effect on human androgen-sensitive LNCaP cell line.

    PubMed

    Cortés-Benítez, Francisco; Cabeza, Marisa; Ramírez-Apan, María Teresa; Alvarez-Manrique, Berenice; Bratoeff, Eugene

    2016-10-01

    In this study, we report the synthesis and anti-proliferative effect of a set of eight androst-4-ene-3-one derivatives with different arylcarbamoyl groups at C-17. The novel compounds were prepared from commercially available 3β-hydroxy-5-pregnen-20-one and evaluated against the androgen-sensitive human prostate adenocarcinoma LNCaP cell line. The cancerous cells were exposed to 50 μM of each compound and the proliferating agent testosterone (T) or dihydrotestosterone (DHT). The most potent compounds from this assay were further tested against the androgen-insensitive PC3 cell line. We also demonstrate the activity of these compounds on rat peripheral blood mononuclear cells for comparison. Both 17β-N-[3,5-bis(trifluoromethyl)phenylcarbamoyl]androst-4-ene-3-one (6f) and 17β-N-(1,3-thiazol-2-ylcarbamoyl)androst-4-ene-3-one (6g) exhibited a higher growth inhibitory effect than commercially available drugs finasteride, flutamide and ketoconazole on LNCaP cells in the presence and absence of androgens. In addition, 6f and 6g demonstrated high potency on PC3 cells suggesting an androgen-independent anti-proliferative effect. Moreover, the novel compounds showed a small effect on rat mononuclear cells, an indication of low toxicity. PMID:27423983

  19. Synthesis of 17β-N-arylcarbamoylandrost-4-en-3-one derivatives and their anti-proliferative effect on human androgen-sensitive LNCaP cell line.

    PubMed

    Cortés-Benítez, Francisco; Cabeza, Marisa; Ramírez-Apan, María Teresa; Alvarez-Manrique, Berenice; Bratoeff, Eugene

    2016-10-01

    In this study, we report the synthesis and anti-proliferative effect of a set of eight androst-4-ene-3-one derivatives with different arylcarbamoyl groups at C-17. The novel compounds were prepared from commercially available 3β-hydroxy-5-pregnen-20-one and evaluated against the androgen-sensitive human prostate adenocarcinoma LNCaP cell line. The cancerous cells were exposed to 50 μM of each compound and the proliferating agent testosterone (T) or dihydrotestosterone (DHT). The most potent compounds from this assay were further tested against the androgen-insensitive PC3 cell line. We also demonstrate the activity of these compounds on rat peripheral blood mononuclear cells for comparison. Both 17β-N-[3,5-bis(trifluoromethyl)phenylcarbamoyl]androst-4-ene-3-one (6f) and 17β-N-(1,3-thiazol-2-ylcarbamoyl)androst-4-ene-3-one (6g) exhibited a higher growth inhibitory effect than commercially available drugs finasteride, flutamide and ketoconazole on LNCaP cells in the presence and absence of androgens. In addition, 6f and 6g demonstrated high potency on PC3 cells suggesting an androgen-independent anti-proliferative effect. Moreover, the novel compounds showed a small effect on rat mononuclear cells, an indication of low toxicity.

  20. Towards a non-animal risk assessment for anti-androgenic effects in humans.

    PubMed

    Dent, Matthew P; Carmichael, Paul L; Jones, Kevin C; Martin, Francis L

    2015-10-01

    Toxicology testing is undergoing a transformation from a system based on high-dose studies in laboratory animals to one founded primarily on in vitro methods that evaluate changes in normal cellular signalling pathways using human-relevant cells or tissues. We review the tools and approaches that could be used to develop a non-animal safety assessment for anti-androgenic effects in humans, with a focus on the molecular initiating events (MIEs) that human disorders indicate critical for normal functioning of the hypothalamus-pituitary-testicular (HPT) axis. In vitro test systems exist which can be used to characterize the effects of test chemicals on some MIEs such as androgen receptor antagonism, inhibition of steroidogenic enzymes or 5α-reductase inhibition. When used alongside information describing the pharmacokinetics of a specific chemical exposure, these could be used to inform a pathways-based safety assessment. However, some parts of the HPT axis such as events occurring in the hypothalamus or pituitary are not well represented by accepted in vitro methods. In vitro tools to characterize perturbations in these events need to be developed before a fully integrated model of the HPT axis can be described. Knowledge gaps also exist which prevent us from using in vitro data to predict the type and severity of in vivo effect(s) that could arise from a given level of in vitro anti-androgenic activity. This means that more work is needed to reliably link an MIE with an adverse outcome. However, especially for chemicals with low anti-androgenic activity, human exposure data can be used to put in vitro mode of action data into context for risk-based safety decision-making.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. Psoralidin, An Herbal Molecule Inhibits PI3K Mediated Akt Signaling In Androgen Independent Prostate Cancer (AIPC) Cells

    PubMed Central

    Kumar, Raj; Srinivasan, Sowmyalakshmi; Koduru, Srinivas; Pahari, Pallab; Rohr, Jürgen; Kyprianou, Natasha; Damodaran, Chendil

    2008-01-01

    The protein kinase Akt plays an important role in cell proliferation and survival in many cancers, including prostate cancer. Due to its kinase activity, it serves as a molecular conduit for inhibiting apoptosis and promoting angiogenesis in most cell types. In most of the prostate tumors, Akt signaling is constitutively activated due to the deletion or mutation of the tumor suppressor PTEN, which negatively regulates PI3K through lipid phosphatase activity. Recently, we identified a natural compound, psoralidin, which inhibits Akt phosphorylation and its consequent activation in androgen independent prostate cancer cells (AIPC). Furthermore, ectopic expression of Akt renders AIPC cells resistant chemotherapy; however, psoralidin overcomes Akt-mediated resistance and induces apoptosis in AIPC cells. While dissecting the molecular events, both upstream and downstream of Akt, we found that psoralidin inhibits PI3 kinase activation and transcriptionally represses the activation of NF-κB and its target genes (Bcl-2, Survivin, and Bcl-xL, etc.), which results in the inhibition of cell viability and induction of apoptosis in PC-3 and DU-145 cells. Interestingly, psoralidin selectively targets cancer cells, without causing any toxicity to normal prostate epithelial cells. In vivo xenograft assays substantiate these in vitro findings, and show psoralidin inhibits prostate tumor growth in nude mice. Our findings are of therapeutic significance in the management of prostate cancer patients with advanced or metastatic disease, as they provide new directions for the development of a phyotochemical-based platform for prevention and treatment strategies for AIPC. PMID:19223576

  6. Androgen receptor accelerates premature senescence of human dermal papilla cells in association with DNA damage.

    PubMed

    Yang, Yi-Chien; Fu, Hung-Chun; Wu, Ching-Yuan; Wei, Kuo-Ting; Huang, Ko-En; Kang, Hong-Yo

    2013-01-01

    The dermal papilla, located in the hair follicle, expresses androgen receptor and plays an important role in hair growth. Androgen/Androgen receptor actions have been implicated in the pathogenesis of androgenetic alopecia, but the exact mechanism is not well known. Recent studies suggest that balding dermal papilla cells exhibit premature senescence, upregulation of p16(INK4a), and nuclear expression of DNA damage markers. To investigate whether androgen/AR signaling influences the premature senescence of dermal papilla cells, we first compared frontal scalp dermal papilla cells of androgenetic alopecia patients with matched normal controls and observed that premature senescence is more prominent in the dermal papilla cells of androgenetic alopecia patients. Exposure of androgen induced premature senescence in dermal papilla cells from non-balding frontal and transitional zone of balding scalp follicles but not in beard follicles. Overexpression of the AR promoted androgen-induced premature senescence in association with p16(INK4a) upregulation, whereas knockdown of the androgen receptor diminished the effects of androgen. An analysis of γ-H2AX expression in response to androgen/androgen receptor signaling suggested that DNA damage contributes to androgen/androgen receptor-accelerated premature senescence. These results define androgen/androgen receptor signaling as an accelerator of premature senescence in dermal papilla cells and suggest that the androgen/androgen receptor-mediated DNA damage-p16(INK4a) axis is a potential therapeutic target in the treatment of androgenetic alopecia.

  7. 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...

  8. Structural basis for androgen specificity and oestrogen synthesis in human aromatase

    SciTech Connect

    Ghosh, Debashis; Griswold, Jennifer; Erman, Mary; Pangborn, Walter

    2009-03-06

    Aromatase cytochrome P450 is the only enzyme in vertebrates known to catalyse the biosynthesis of all oestrogens from androgens. Aromatase inhibitors therefore constitute a frontline therapy for oestrogen-dependent breast cancer. In a three-step process, each step requiring 1 mol of O{sub 2}, 1 mol of NADPH, and coupling with its redox partner cytochrome P450 reductase, aromatase converts androstenedione, testosterone and 16{alpha}-hydroxytestosterone to oestrone, 17{beta}-oestradiol and 17{beta},16{alpha}-oestriol, respectively. The first two steps are C19-methyl hydroxylation steps, and the third involves the aromatization of the steroid A-ring, unique to aromatase. Whereas most P450s are not highly substrate selective, it is the hallmark androgenic specificity that sets aromatase apart. The structure of this enzyme of the endoplasmic reticulum membrane has remained unknown for decades, hindering elucidation of the biochemical mechanism. Here we present the crystal structure of human placental aromatase, the only natural mammalian, full-length P450 and P450 in hormone biosynthetic pathways to be crystallized so far. Unlike the active sites of many microsomal P450s that metabolize drugs and xenobiotics, aromatase has an androgen-specific cleft that binds the androstenedione molecule snugly. Hydrophobic and polar residues exquisitely complement the steroid backbone. The locations of catalytically important residues shed light on the reaction mechanism. The relative juxtaposition of the hydrophobic amino-terminal region and the opening to the catalytic cleft shows why membrane anchoring is necessary for the lipophilic substrates to gain access to the active site. The molecular basis for the enzyme's androgenic specificity and unique catalytic mechanism can be used for developing next-generation aromatase inhibitors.

  9. Camptothecin sensitizes androgen-independent prostate cancer cells to anti-Fas-induced apoptosis

    PubMed Central

    Costa-Pereira, A P; Cotter, T G

    1999-01-01

    Despite expressing both Fas and Fas ligand, DU145 and LNCaP prostate cancer cells were resistant to anti-Fas-induced cell death. Resistance to Fas-mediated cytotoxicity could be overcome in DU145, but not in LNCaP, cells by pretreating cells with sublethal doses of cytotoxic drugs, such as camptothecin. Activated caspases were shown to be required for this cytotoxicity. Indeed, poly(ADP-Ribose) polymerase was shown to be proteolytically cleaved in cells treated with camptothecin plus anti-Fas, but not in cells treated with anti-Fas only. Moreover, pretreatment of cells with ZVAD completely blocked camptothecin-mediated Fas-induced apoptosis. Sensitization of cells to Fas-induced cell death did not involve up-regulation of Fas or FasL, and it was independent of alterations in the cell cycle. Reactive oxygen intermediates (ROI) have been shown to be important mediators of drug-induced apoptosis. Here, we demonstrate that treatment of DU145 cells with camptothecin, anti-Fas, or both, did not alter the intracellular levels of peroxide or superoxide anion. © 1999 Cancer Research Campaign PMID:10408840

  10. Estrogenicity and androgenicity screening of PCB sulfate monoesters in human breast cancer MCF-7 cells.

    PubMed

    Flor, Susanne; He, Xianran; Lehmler, Hans-Joachim; Ludewig, Gabriele

    2016-02-01

    Recent studies identified polychlorinated biphenyl (PCB) sulfate esters as a major product of PCB metabolism. Since hydroxy-PCBs (HO-PCBs), the immediate precursors of PCB sulfates and important contributors to PCB toxicity, were shown to have estrogenic activity, we investigated the estrogenicity/androgenicty of a series of PCB sulfate metabolites. We synthesized the five possible structural sulfate monoester metabolites of PCB 3, a congener shown to be biotransformed to sulfates, a sulfate ester of the paint-specific congener PCB 11, and sulfate monoesters of two HO-PCBs reported to interact with sulfotransferases (PCB 39, no ortho chlorines, and PCB 53, 3 ortho chlorines). We tested these PCB sulfates and 4'-HO-PCB 3 as positive control for estrogenic, androgenic, anti-estrogenic, and anti-androgenic activity in the E- and A-screen with human breast cancer MCF7-derived cells at 100 μM-1 pM concentrations. Only 4'-HO-PCB 3 was highly cytotoxic at 100 μM. We observed structure-activity relationships: compounds with a sulfate group in the chlorine-containing ring of PCB 3 (2PCB 3 and 3PCB 3 sulfate) showed no interaction with the estrogen (ER) and androgen (AR) receptor. The 4'-HO-PCB 3 and its sulfate ester had the highest estrogenic effect, but at 100-fold different concentrations, i.e., 1 and 100 μM, respectively. Four of the PCB sulfates were estrogenic (2'PCB 3, 4'PCB 3, 4'PCB 39, and 4'PCB 53 sulfates; at 100 μM). These sulfates and 3'PCB 3 sulfate also exhibited anti-estrogenic activity, but at nM and pM concentrations. The 4'PCB 3 sulfate (para-para' substituted) had the strongest androgenic activity, followed by 3'PCB 3, 4'PCB 53, 4PCB11, and 4PCB 39 sulfates and the 4'HO-PCB 3. In contrast, anti-androgenicity was only observed with the two compounds that have the sulfate group in ortho- or meta- position in the second ring (2'PCB 3 and 3'PCB 3 sulfate). No dose-response was observed in any screen, but, with exception of estrogenic activity (only seen

  11. Variable Metastatic Potentials Correlate with Differential Plectin and Vimentin Expression in Syngeneic Androgen Independent Prostate Cancer Cells

    PubMed Central

    Burch, Tanya C.; Watson, Megan T.; Nyalwidhe, Julius O.

    2013-01-01

    Prostate cancer is a clinically heterogeneous disease, ranging from indolent asymptomatic disease to very aggressive metastatic and life threatening forms of the disease. Distant metastasis represents the major lethal cause of prostate cancer. The most critical clinical challenge in the management of the patients is identifying those individuals at risk of developing metastatic disease. To understand the molecular mechanisms of prostate cancer metastasis and identify markers with metastatic potential, we have analyzed protein expression in two syngeneic prostate cancer cells lines PC3-N2 and PC3-ML2 using isobaric tags for relative and absolute quantitation labeling and multi-dimensional protein identification technology liquid chromatography matrix assisted laser desorption ionization tandem mass spectrometry. PC3-N2 is lowly metastatic while PC3-ML2 highly metastatic. A total of 1,756 proteins were identified in the analyses with 130 proteins showing different expression levels (p<0.01) in the two cell lines. Out of these, 68 proteins were found to be significantly up-regulated while 62 are significantly down-regulated in PC3-ML2 cells compared with PC3-N2 cells. The upregulation of plectin and vimentin which were the most significantly differentially expressed were validated by Western blot and their functional relevance with respect to invasion and migration was determined by siRNA gene silencing. To our knowledge, this study is the first to demonstrate that up-regulation of vimentin and plectin expression positively correlates with the invasion and metastasis of androgen-independent PCA. PMID:23717685

  12. Gene expression profiling of the androgen independent prostate cancer cells demonstrates complex mechanisms mediating resistance to docetaxel

    PubMed Central

    Desarnaud, Frank; Geck, Peter; Parkin, Christopher; Carpinito, Gino

    2011-01-01

    The molecular mechanisms conferring resistance to docetaxel in prostate cancer patients remain partially understood. We generated docetaxel resistant derivatives of the androgen independent prostate cancer cell lines PC-3 and DU-145. Docetaxel rapidly induces DU-145 cell death via apoptosis and the drug resistant cells were produced by periodically exposing proliferating DU-145 cultures to small doses of docetaxel. In PC-3 cells docetaxel induces delayed cell death via mitotic catastrophe evident by profound multinucleation and formation of giant cells. Mononucleated progeny of the giant PC-3 cells shows significant resistance to docetaxel. Gene expression profiling of these docetaxel resistant PC-3 cells revealed sets of docetaxel inducible and constitutively expressed genes associated with major cancer pathways. A contradictory overlap with DU-145 docetaxel resistant cells was also found. Analyses suggested significant changes associated with apoptotic function, DNA repair, cell growth, survival and proliferation, metabolism, maintenance of cytoskeleton and extracellular matrix formation. These cellular processes often contribute to drug resistance and our study identified a set of genes managing this phenotype. Additional analyses of the drug resistant PC-3 cells using shRNA constructs determined direct relevance of Cyclin G2 to docetaxel resistance as well as prevention of multinucleation, whereas the knockdown of upregulated CYP1B1 showed no effect on either of these processes. Downregulated GBP1 was explored by ectopic overexpression and even though GBP1 has a potential to mediate resistance to docetaxel, it was not utilized in PC-3 cells. The results suggest complex combination of gene expression pattern changes that enables resistance to docetaxel while preventing death via multinucleation. PMID:21057205

  13. Megalin and androgen receptor gene expression in young and old human skeletal muscle before and after three sequential exercise bouts.

    PubMed

    Poole, Chris N; Roberts, Michael D; Dalbo, Vincent J; Sunderland, Kyle L; Kerksick, Chad M

    2011-02-01

    Androgen signaling occurs primarily via the androgen receptor. Megalin, a low-density lipoprotein endocytic receptor located in various mammalian tissues, has been recently shown to facilitate sex hormone–binding globulin (SHBG) steroid complexes across cell membranes. The purpose of this investigation is to determine if the megalin gene is expressed in human skeletal muscle and if present to determine how megalin and androgen receptor mRNA expression change in response to sequential exercise bouts with respect to aging. Ten younger (age: 18-25 years) and 10 older (age: 60-75 years) men completed 3 workouts (M, W, F) each consisting of 9 sets of lower-body exercises with 10 repetitions per set at 80% 1 repetition maximum. Vastus lateralis muscle biopsies were extracted at baseline (T1), 48 hours after workout 1 (T2) and 2 (T3), and 24 hours after workout 3 (T4), and blood samples were collected before and 5 minutes after each workout. Muscle was analyzed for megalin and androgen receptor expression using gene-specific primers and SYBR green chemistry, and blood was analyzed for serum testosterone, SHBG, and the free androgen index. Megalin was expressed in both young and old subjects across all time points, although no between- or within-group mean differences were detected at any time point. Androgen receptor was expressed higher in young men at all time points compared to in old men (p < 0.05), and a significant correlation (p < 0.05; r = 0.506) was found between serum testosterone and androgen receptor after workout 1. Based on our data, the gene coding for megalin is expressed inside skeletal muscle, but its role, if any, in steroid cellular transport cannot be determined. This finding could lay the groundwork for more mechanistic investigations to better delineate its functional role and its potential as a therapeutic adjunct for androgen-related disorders in healthy and aged populations. PMID:21322835

  14. Novel stably transfected human reporter cell line AIZ-AR as a tool for an assessment of human androgen receptor transcriptional activity.

    PubMed

    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.

  15. Sodium butyrate regulates androgen receptor expression and cell cycle arrest in human prostate cancer cells.

    PubMed

    Kim, Jeonga; Park, Hyeyoung; Im, Ji Young; Choi, Wahn Soo; Kim, Hyung Sik

    2007-01-01

    Histone deacetylase (HDAC) inhibitors have been shown to modify the expression of a variety of genes related to cell cycle regulation and apoptosis in several cancer cells. However, the precise mode of action of HDAC inhibitors in prostate cancer cells is not completely understood. This study examined whether an HDAC inhibitor affects cell death in human prostate cancer cells through the epigenetic regulation of androgen receptor (AR) expression. The molecular mechanism of the HDAC inhibitor, sodium butyrate, on the epigenetic alterations of cell cycle regulators was evaluated in androgen-dependent human prostate cancer LNCaP cells. The expression levels of acetylated histone H3 and H4 increased significantly after 48 h treatment with sodium butyrate. Sodium butyrate induced the expression of AR after 48 h treatment. In addition, immunofluorescence assay revealed the nuclear localization of the AR after sodium butyrate treatment. Sodium butyrate also significantly decreased the expression of the cell cycle regulatory proteins (cyclin D1/cyclin dependent kinase (CDK)4, CDK6, and cyclin E/CDK2) in the LNCaP cells after 48 h treatment. Furthermore, p21Waf1/Cip1 and p27Kip1 were upregulated as a result of the sodium butyrate treatment. These results suggest that sodium butyrate effectively inhibited cell proliferation and induced apoptosis of human prostate cancer cells by altering the expression of cell cycle regulators and AR. This study indicated that sodium butyrate may be a potential agent in prostate cancer treatment.

  16. 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

  17. 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

  18. Mechanisms of androgen deficiency in human immunodeficiency virus-infected women with the wasting syndrome.

    PubMed

    Grinspoon, S; Corcoran, C; Stanley, T; Rabe, J; Wilkie, S

    2001-09-01

    Although prior studies suggest reduced androgen levels in women with acquired immune deficiency syndrome wasting, little is known regarding the regulation of adrenal and ovarian androgen secretion in such patients. We investigated ovarian and adrenal function in 13 human immunodeficiency virus-infected women with acquired immune deficiency syndrome wasting and 21 age- and body mass index-matched healthy control subjects studied in the early follicular phase. Subjects received hCG (5000 U, im) on d 1 and Cosyntropin (0.25 mg, i.v.) on d 3 after dexamethasone (1 mg, orally, at 2400 h) pretreatment on d 2. At baseline, human immunodeficiency virus-infected subjects demonstrated significantly reduced T [18 +/- 2 vs. 25 +/- 2 ng/dl (0.6 +/- 0.1 vs. 0.9 +/- 0.1 nmol/liter); P = 0.02], free T [1.5 +/- 0.1 vs. 2.4 +/- 0.2 pg/ml (5.3 +/- 0.5 vs. 8.3 +/- 0.6 pmol/liter); P = 0.001], androstenedione [119 +/- 6 vs. 162 +/- 14 ng/dl (4.16 +/- 0.20 vs. 5.66 +/- 0.48 nmol/liter); P = 0.02], and dehydroepiandrosterone sulfate [0.96 +/- 0.17 vs. 1.55 +/- 0.19 microg/ml (2.6 +/- 0.5 vs. 4.2 +/- 0.5 micromol/liter); P = 0.047] levels compared with the control subjects. T [8 +/- 2 vs. 6 +/- 2 ng/dl (0.3 +/- 0.1 vs. 0.2 +/- 0.1 nmol/liter); P = 0.48], free T [0.5 +/- 0.2 vs. 0.4 +/- 0.1 pg/ml (1.7 +/- 0.7 vs. 1.5 +/- 0.5 pmol/liter); P = 0.85], 17 hydroxyprogesterone [0.5 +/- 0.2 vs. 0.7 +/- 0.2 microg/liter (1.6 +/- 0.6 vs. 2.0 +/- 0.6 nmol/liter); P = 0.63], and androstenedione [-1 +/- 12 vs. 8 +/- 11 ng/dl (-0.03 +/- 0.42 vs. 0.28 +/- 0.39 nmol/liter), P = 0.61] responses to hCG were not different between the groups. Cortisol responses were increased and dehydroepiandrosterone sulfate responses were decreased in the human immunodeficiency virus-infected vs. control subjects after ACTH stimulation. The ratio of DHEA to cortisol was significantly decreased at 60 (71 +/- 11 vs. 107 +/- 10; P = 0.02) and 90 (63 +/- 8 vs. 102 +/- 9; P = 0.004) min post-ACTH in the human immunodeficiency

  19. X-ray structure of human aromatase reveals an androgen-specific active site.

    PubMed

    Ghosh, Debashis; Griswold, Jennifer; Erman, Mary; Pangborn, Walter

    2010-02-28

    Aromatase is a unique cytochrome P450 that catalyzes the removal of the 19-methyl group and aromatization of the A-ring of androgens for the synthesis of estrogens. All human estrogens are synthesized via this enzymatic aromatization pathway. Aromatase inhibitors thus constitute a frontline therapy for estrogen-dependent breast cancer. Despite decades of intense investigation, this enzyme of the endoplasmic reticulum membrane has eluded all structure determination efforts. We have determined the crystal structure of the highly active aromatase purified from human placenta, in complex with its natural substrate androstenedione. The structure shows the binding mode of androstenedione in the catalytically active oxidized high-spin ferric state of the enzyme. Hydrogen bond-forming interactions and tight packing hydrophobic side chains that complement the puckering of the steroid backbone provide the molecular basis for the exclusive androgenic specificity of aromatase. Locations of catalytic residues and water molecules shed new light on the mechanism of the aromatization step. The structure also suggests a membrane integration model indicative of the passage of steroids through the lipid bilayer.

  20. Testosterone modulates mitochondrial aconitase in the full-length human androgen receptor-transfected PC-3 prostatic carcinoma cells.

    PubMed

    Juang, H-H; Hsieh, M-L; Tsui, K-H

    2004-08-01

    In vitro studies indicated that dihydrotestosterone (DHT) stimulates the enzymatic activity of the mitochondrial aconitase (mACON) in androgen-sensitive prostatic carcinoma cells, LNCaP. Cell proliferation assay determined that DHT doubles the optimal proliferation response of LNCaP cells. The androgen-insensitive human prostatic carcinoma cells, PC-3, were overexpressed in the human androgen receptor to assess the involvement of the native androgen receptor in the regulation by DHT of mACON gene expression. A stable-transfected clone that expresses the full-length androgen receptor was selected and termed PCAR9. The results revealed that DHT-treated PCAR9 cells paradoxically not only reduced the enzymatic activity of mACON but also blocked the biosynthesis of intracellular ATP attenuating cell proliferation. Transient gene expression assay indicated that DHT divergently regulates the promoter activity of the mACON gene in LNCaP and PCAR9 cells. This study suggested that DHT regulates mACON gene expression and the proliferation of cells in a receptor-dependent model through modulation by unidentified non-receptor factors. PMID:15291747

  1. Constitutively-active androgen receptor variants function independently of the HSP90 chaperone but do not confer resistance to HSP90 inhibitors.

    PubMed

    Gillis, Joanna L; Selth, Luke A; Centenera, Margaret M; Townley, Scott L; Sun, Shihua; Plymate, Stephen R; Tilley, Wayne D; Butler, Lisa M

    2013-05-01

    The development of lethal, castration resistant prostate cancer is associated with adaptive changes to the androgen receptor (AR), including the emergence of mutant receptors and truncated, constitutively active AR variants. AR relies on the molecular chaperone HSP90 for its function in both normal and malignant prostate cells, but the requirement for HSP90 in environments with aberrant AR expression is largely unknown. Here, we investigated the efficacy of three HSP90 inhibitors, 17-AAG, HSP990 and AUY922, against clinically-relevant AR missense mutants and truncated variants. HSP90 inhibition effectively suppressed the signaling of wild-type AR and all AR missense mutants tested. By contrast, two truncated AR variants, AR-V7 and ARv567es, exhibited marked resistance to HSP90 inhibitors. Supporting this observation, nuclear localization of the truncated AR variants was not affected by HSP90 inhibition and AR variant:HSP90 complexes could not be detected in prostate cancer cells. Interestingly, HSP90 inhibition resulted in accumulation of AR-V7 and ARv567es in both cell lines and human tumor explants. Despite the apparent independence of AR variants from HSP90 and their treatment-associated induction, the growth of cell lines with endogenous or enforced expression of AR-V7 or ARv567es remained highly sensitive to AUY922. This study demonstrates that functional AR variant signaling does not confer resistance to HSP90 inhibition, yields insight into the interaction between AR and HSP90 and provides further impetus for the clinical application of HSP90 inhibitors in advanced prostate cancer.

  2. Androgen deprivation causes truncation of the C-terminal region of androgen receptor in human prostate cancer LNCaP cells.

    PubMed

    Harada, Naoki; Inoue, Kaoru; Yamaji, Ryoichi; Nakano, Yoshihisa; Inui, Hiroshi

    2012-06-01

    The androgen receptor (AR) acts as a ligand-dependent transcription factor, whereas mutant AR lacking the C-terminal ligand-binding domain functions in a ligand-independent manner. In the present study we report that the C-terminal truncated AR, which we named AR-NH1 (the N-terminal fragment of AR cleaved in the neighborhood of helix 1 of the ligand-binding domain), is produced in LNCaP prostatic carcinoma cells. The AR-NH1 of ~90 kDa was observed in an androgen-independent LNCaP subline and was further accumulated by the proteasome inhibitor MG132. MG132 treatment caused the accumulation of AR-NH1 even in parent LNCaP cells. AR-NH1 was produced in the absence of ligand or in the presence of the AR antagonist bicalutamide, whereas AR agonists suppressed its production. AR-NH1 was detected with different AR antibodies recognizing amino acid residues 1-20 and 300-316 and was also generated from exogenous AR. Both siRNA-mediated AR knockdown and treatment with a serine protease inhibitor (4-(2-aminoethyl)-benzenesulfonyl fluoride) reduced AR-NH1 levels. According to the predicted cleavage site (between amino acid residues 660-685) and its nuclear localization, it is assumed that AR-NH1 functions as a constitutively active transcription factor. These data suggest that AR-NH1 is produced under hormone therapy and contributes to the development of castration-resistant prostate cancer due to its ligand-independent transcriptional activity.

  3. Androgenic Biomarker Profiling in Human Matrices and Cell Culture Samples Using High Through put, Electrospray Tandem Mass Spectrometry

    PubMed Central

    Wilton, John H.; Titus, Mark A.; Efstathiou, Eleni; Fetterly, Gerald J.; Mohler, James L.

    2015-01-01

    BACKGROUND A high throughput, high pressure liquid chromatographic (HPLC) method with triple quadrupole mass spectral detection (LC/MS/MS) was validated for the measurement of 5 endogenous androgens in human plasma and serum and applied to various in vivo and in vitro study samples to pursue a better understanding of the interrelationship of the androgen axis, intracrine metabolism, and castration-recurrent prostate cancer (CaP). METHODS A Shimadzu HPLC system interfaced with a Sciex QTRAP 5500 mass spectrometer with electrospray ionization was used with inline column-switching. Samples were liquid/liquid extracted and chromatographed on a Luna C18(2) column at 60°C with a biphasic gradient using a 15-min run time. RESULTS The method was validated for five androgens in human plasma and serum, and applied to four sets of samples. Plasma (n = 188) and bone marrow aspirate (n = 129) samples from patients with CaP, who received abiraterone acetate plus prednisone for up to 945 days (135 weeks), had undetectable androgens after 8 weeks of treatment. Plasma dehydroepiandrosterone (DHEA) concentrations were higher in African Americans than Caucasian Americans with newly diagnosed CaP. Analysis of prostate tumor tissue homogenates demonstrated reproducible testosterone (T) and dihydrotestosterone (DHT) concentrations with a minimal sample size of ~1.0–2.0 mg of tissue. Finally, cell pellet and media samples from the LNCaP C4-2 cell line showed conversion of T to DHT. CONCLUSION The proposed LC/MS/MS method was validated for quantitation of five endogenous androgens in human plasma and serum, and effectively profiles androgens in clinical specimens and cell culture samples. PMID:24847527

  4. Afzelin exhibits anti-cancer activity against androgen-sensitive LNCaP and androgen-independent PC-3 prostate cancer cells through the inhibition of LIM domain kinase 1

    PubMed Central

    ZHU, KAI-CHANG; SUN, JIAN-MEI; SHEN, JIAN-GUO; JIN, JI-ZHONG; LIU, FENG; XU, XIAO-LIN; CHEN, LIN; LIU, LIN-TAO; LV, JIA-JU

    2015-01-01

    Prostate cancer presents high occurrence worldwide. Medicinal plants are a major source of novel and potentially therapeutic molecules; therefore, the aim of the present study was to investigate the possible anti-prostate cancer activity of afzelin, a flavonol glycoside that was previously isolated from Nymphaea odorata. The effect of afzelin on the proliferation of androgen-sensitive LNCaP and androgen-independent PC-3 cells was evaluated by performing a water soluble tetrazolium salt-1 assay. In addition, the effect of afzelin on the cell cycle of the LNCaP and PC-3 prostate cancer cell lines was evaluated. Western blot analysis was performed to evaluate the effect of afzelin on the kinases responsible for the regulation of actin organization. Afzelin was identified to inhibit the proliferation of LNCaP and PC3 cells, and block the cell cycle in the G0 phase. The anticancer activity of afzelin in these cells was determined to be due to inhibition of LIM domain kinase 1 expression. Thus, the in vitro efficacy of afzelin against prostate cancer is promising; however, additional studies on different animal models are required to substantiate its anticancer potential. PMID:26622852

  5. Androgen-Sensitized Apoptosis of HPr-1AR Human Prostate Epithelial Cells

    PubMed Central

    Chen, Congcong; Dienhart, Jason A.; Bolton, Eric C.

    2016-01-01

    Androgen receptor (AR) signaling is crucial to the development and homeostasis of the prostate gland, and its dysregulation mediates common prostate pathologies. The mechanisms whereby AR regulates growth suppression and differentiation of luminal epithelial cells in the prostate gland and proliferation of malignant versions of these cells have been investigated in human and rodent adult prostate. However, the cellular stress response of human prostate epithelial cells is not well understood, though it is central to prostate health and pathology. Here, we report that androgen sensitizes HPr-1AR and RWPE-AR human prostate epithelial cells to cell stress agents and apoptotic cell death. Although 5α-dihydrotestosterone (DHT) treatment alone did not induce cell death, co-treatment of HPr-1AR cells with DHT and an apoptosis inducer, such as staurosporine (STS), TNFt, or hydrogen peroxide, synergistically increased cell death in comparison to treatment with each apoptosis inducer by itself. We found that the synergy between DHT and apoptosis inducer led to activation of the intrinsic/mitochondrial apoptotic pathway, which is supported by robust cleavage activation of caspase-9 and caspase-3. Further, the dramatic depolarization of the mitochondrial membrane potential that we observed upon co-treatment with DHT and STS is consistent with increased mitochondrial outer membrane permeabilization (MOMP) in the pro-apoptotic mechanism. Interestingly, the synergy between DHT and apoptosis inducer was abolished by AR antagonists and inhibitors of transcription and protein synthesis, suggesting that AR mediates pro-apoptotic synergy through transcriptional regulation of MOMP genes. Expression analysis revealed that pro-apoptotic genes (BCL2L11/BIM and AIFM2) were DHT-induced, whereas pro-survival genes (BCL2L1/BCL-XL and MCL1) were DHT-repressed. Hence, we propose that the net effect of these AR-mediated expression changes shifts the balance of BCL2-family proteins, such that

  6. Cholesterol synthesis inhibitor RO 48-8071 suppresses transcriptional activity of human estrogen and androgen receptor.

    PubMed

    Mafuvadze, Benford; Liang, Yayun; Hyder, Salman M

    2014-10-01

    Breast cancer cells express enzymes that convert cholesterol, the synthetic precursor of steroid hormones, into estrogens and androgens, which then drive breast cancer cell proliferation. In the present study, we sought to determine whether oxidosqualene cyclase (OSC), an enzyme in the cholesterol biosynthetic pathway, may be targeted to suppress progression of breast cancer cells. In previous studies, we showed that the OSC inhibitor RO 48-8071 (RO) may be a ligand which could potentially be used to control the progression of estrogen receptor-α (ERα)-positive breast cancer cells. Herein, we showed, by real-time PCR analysis of mRNA from human breast cancer biopsies, no significant differences in OSC expression at various stages of disease, or between tumor and normal mammary cells. Since the growth of hormone-responsive tumors is ERα-dependent, we conducted experiments to determine whether RO affects ERα. Using mammalian cells engineered to express human ERα or ERβ protein, together with an ER-responsive luciferase promoter, we found that RO dose-dependently inhibited 17β-estradiol (E2)-induced ERα responsive luciferase activity (IC50 value, ~10 µM), under conditions that were non-toxic to the cells. RO was less effective against ERβ-induced luciferase activity. Androgen receptor (AR) mediated transcriptional activity was also reduced by RO. Notably, while ERα activity was reduced by atorvastatin, the HMG-CoA reductase inhibitor did not influence AR activity, showing that RO possesses broader antitumor properties. Treatment of human BT-474 breast cancer cells with RO reduced levels of estrogen-induced PR protein, confirming that RO blocks ERα activity in tumor cells. Our findings demonstrate that an important means by which RO suppresses hormone-dependent growth of breast cancer cells is through its ability to arrest the biological activity of ERα. This warrants further investigation of RO as a potential therapeutic agent for use against hormone

  7. Glucuronidation of anabolic androgenic steroids by recombinant human UDP-glucuronosyltransferases.

    PubMed

    Kuuranne, Tiia; Kurkela, Mika; Thevis, Mario; Schänzer, Wilhelm; Finel, Moshe; Kostiainen, Risto

    2003-09-01

    A multidimensional study on the glucuronidation of anabolic androgenic steroids and their phase I metabolites by 11 recombinant human UDP-glucuronosyltransferases (UGTs) was carried out using liquid chromatographic-tandem mass spectrometric analyses. Large differences between the enzymes with respect to the conjugation profiles of the 11 tested aglycones were detected. Two UGTs, 1A6 and 1A7, did not exhibit measurable activity toward any of the aglycones that were examined in this study. Regioselectivity was demonstrated by UGTs 1A8, 1A9, and 2B15 that preferentially catalyzed hydroxyl glucuronidation at the 17beta-position. Most of the other enzymes glucuronidated hydroxyl groups at both the 3alpha- and the 17beta-positions. Clear stereoselectivity was observed in glucuronidation of diastereomeric nandrolone metabolites (5alpha-estran-3alpha-ol-17-one and 5beta-estran-3alpha-ol-17-one), whereas such specificity was not seen when analogous methyltestosterone metabolites were assayed. UGTs 1A1, 1A3, 1A4, 1A8, 1A9, 1A10, 2B4, 2B7, and 2B15 readily glucuronidated 5alpha-androstane-3alpha,17beta-diol, but none of them exhibited methyltestosterone glucuronidation activity. In agreement with the latter observations, we found that the methyltestosterone glucuronidation activity of human liver microsomes is extremely low, whereas in induced rat liver microsomes it was significantly higher. The homology among UGTs 1A7 to 1A10 at the level of amino acid sequence is very high, and it was thus surprising to find large differences in their activity toward this set of aglycones. Furthermore, the high activity of UGT1A8 and 1A10 toward some of the substrates indicates that extrahepatic enzymes might play a role in the metabolism of anabolic androgenic steroids. PMID:12920167

  8. X inactivation in human testicular tumors. XIST expression and androgen receptor methylation status.

    PubMed Central

    Looijenga, L. H.; Gillis, A. J.; van Gurp, R. J.; Verkerk, A. J.; Oosterhuis, J. W.

    1997-01-01

    In female mammalian cells, inactivation of one of the X chromosomes compensates the increased dosage of X-linked genes as compared with their male counterparts. This process is initiated by the X-inactive specific transcripts of the xist/XIST gene in cis, resulting in methylation of specific sites of genes to be silenced. However, in male germ cells, X inactivation is established by xist/XIST expression only. We investigated the X inactivation pattern in human testicular tumors of different histogenesis by analysis of XIST expression and methylation of the androgen receptor gene. XIST was expressed only in tumors derived from the germ cell lineage with supernumerical X chromosomes: seminomas, nonseminomas, and spermatocytic seminomas. Although low expression was present in testicular parenchyma with spermatogenesis, XIST was expressed at a higher level in parenchyma with carcinoma in situ, the precursor lesion of seminomas and nonseminomas. Despite the consistent expression of XIST in germ-cell-derived tumors with gain of X chromosomes, methylation of the androgen receptor gene was present in all differentiated but only in a proportion of the undifferentiated nonseminomas. This differential pattern of methylation was also found in a number of representative cell lines. Our data indicate that the counting mechanism resulting in X inactivation is functional in testicular cancers of different histogenesis. Moreover, the differentiation-dependent pattern of X inactivation as reported during normal development in the case of multiple X chromosomes by methylation is retained in these tumors. We conclude therefore that X inactivation allows the excessive gain of X chromosomes found in germ-cell-derived tumors of the adult testis. In addition, this offers an interesting model to study the fundamental mechanisms of these processes. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9250171

  9. Antivascular Effects of Neoadjuvant Androgen Deprivation for Prostate Cancer: An In Vivo Human Study Using Susceptibility and Relaxivity Dynamic MRI

    SciTech Connect

    Alonzi, Roberto; Padhani, Anwar R.; Taylor, N. Jane; Collins, David J.; D'Arcy, James A.; Stirling, J. James; Saunders, Michele I.; Hoskin, Peter J.

    2011-07-01

    Purpose: The antivascular effects of androgen deprivation have been investigated in animal models; however, there has been minimal investigation in human prostate cancer. This study tested the hypothesis that androgen deprivation causes significant reductions in human prostate tumor blood flow and the induction of hypoxia at a magnitude and in a time scale relevant to the neoadjuvant setting before radiotherapy. Methods and Materials: Twenty patients were examined, each with five multi-parameter magnetic resonance imaging scans: two scans before the commencement of androgen suppression, one scan after 1 month of hormone treatment, and two further scans after 3 months of therapy. Quantitative parametric maps of the prostate informing on relative blood flow (rBF), relative blood volume (rBV), vascular permeability (transfer constant [K{sup trans}]), leakage space (v{sub e}) and blood oxygenation (intrinsic relaxivity [R{sub 2}*]) were calculated. Results: Tumor blood volume and blood flow decreased by 83% and 79%, respectively, in the first month (p < 0.0001), with 74% of patients showing significant changes. The proportion of individual patients who achieved significant changes in T1 kinetic parameter values after 3 months of androgen deprivation for tumor measurements was 68% for K{sup trans} and 53% for v{sub e} By 3 months, significant increases in R{sub 2}* had occurred in prostate tumor, with a rise of 41.1% (p < 0.0001). Conclusions: Androgen deprivation induces profound vascular collapse within 1 month of starting treatment. Increased R{sub 2}* in regions of prostate cancer and a decrease in blood volume suggest a reduction in tumor oxygenation.

  10. 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.

  11. 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

  12. 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.

  13. Concomitant abuse of anabolic androgenic steroids and human chorionic gonadotrophin impairs spermatogenesis in power athletes.

    PubMed

    Karila, T; Hovatta, O; Seppälä, T

    2004-05-01

    Abuse of anabolic androgenic steroids (AASs) may be an aetiological factor in male infertility among recreational power athletes. They try to avoid AAS-induced deterioration in spermatogenesis by combining doses of human chorionic gonadotrophin (HCG) and/or antiestrogens with their AAS abuse. Eighteen healthy male power athletes using massive doses of AASs were recruited for the study. Semen samples were collected during AAS abuse and 1.5 and 6 months after cessation of the abuse. They were also asked about their reproductive activity six years after the study. At the end of the AAS cycle, the sperm count was 33 +/- 49 x 10 (6) /ml (mean +/- SD), and only one subject had azoospermia. At 1.5 months after cessation of the AAS cycles, the mean sperm concentration was 30 +/- 42 x 10 (6) /ml, and after six months 77 +/- 70 x 10 (6) /ml. There were significant differences between the sample drawn six months after cessation of AAS abuse and both samples drawn during and 1.5 months after the abuse (p

  14. Human endogenous retrovirus protein Rec interacts with the testicular zinc-finger protein and androgen receptor.

    PubMed

    Kaufmann, Sabine; Sauter, Marlies; Schmitt, Martina; Baumert, Bianca; Best, Barbara; Boese, Annette; Roemer, Klaus; Mueller-Lantzsch, Nikolaus

    2010-06-01

    More than 2000 human endogenous retrovirus (HERV) sequences are present in the human genome, yet only a few are intact and able to produce proteins. The normal functions of these, if any, are unknown, but some HERV proteins have been implicated in cancers, in particular germ-cell cancers. For instance, it has been documented that (i) patients with germ-cell tumours frequently produce antibodies against HERV proteins; (ii) transgenic mice expressing HERV-K (HML-2) rec are prone to testicular carcinoma in situ; and (iii) Rec can bind and suppress a guardian of germline stem-cell pluripotency, the promyelocytic leukaemia zinc-finger protein (PLZF). This study identified the PLZF-related testicular zinc-finger protein (TZFP) as a binding partner of HERV-K (HML-2) Rec. Interactions occurred via the N- and C-terminal domains of Rec and the C-terminal DNA-binding zinc-finger domain of TZFP (aa 375-450). Not much is known about the function of TZFP. The protein is expressed predominantly in the testis, where it functions as a transcriptional repressor that is active during specific stages of spermatogenesis. The most intensely studied function of TZFP is that of a co-repressor of the activated androgen receptor (AR). Here, it was shown that Rec can form a trimeric complex with TZFP and AR, and can relieve the TZFP-mediated repression of AR-induced transactivation. In addition, Rec was able to overcome the direct transcriptional repression by TZFP of the c-myc gene promoter in reporter assays. Thus, HERV-K (HML-2) Rec may function as an oncoprotein by de-repressing oncogenic transcription factors such as AR.

  15. Effects of Long Term Supplementation of Anabolic Androgen Steroids on Human Skeletal Muscle

    PubMed Central

    Yu, Ji-Guo; Bonnerud, Patrik; Eriksson, Anders; Stål, Per S.; Tegner, Yelverton; Malm, Christer

    2014-01-01

    The effects of long-term (over several years) anabolic androgen steroids (AAS) administration on human skeletal muscle are still unclear. In this study, seventeen strength training athletes were recruited and individually interviewed regarding self-administration of banned substances. Ten subjects admitted having taken AAS or AAS derivatives for the past 5 to 15 years (Doped) and the dosage and type of banned substances were recorded. The remaining seven subjects testified to having never used any banned substances (Clean). For all subjects, maximal muscle strength and body composition were tested, and biopsies from the vastus lateralis muscle were obtained. Using histochemistry and immunohistochemistry (IHC), muscle biopsies were evaluated for morphology including fiber type composition, fiber size, capillary variables and myonuclei. Compared with the Clean athletes, the Doped athletes had significantly higher lean leg mass, capillary per fibre and myonuclei per fiber. In contrast, the Doped athletes had significantly lower absolute value in maximal squat force and relative values in maximal squat force (relative to lean body mass, to lean leg mass and to muscle fiber area). Using multivariate statistics, an orthogonal projection of latent structure discriminant analysis (OPLS-DA) model was established, in which the maximal squat force relative to muscle mass and the maximal squat force relative to fiber area, together with capillary density and nuclei density were the most important variables for separating Doped from the Clean athletes (regression  =  0.93 and prediction  =  0.92, p<0.0001). In Doped athletes, AAS dose-dependent increases were observed in lean body mass, muscle fiber area, capillary density and myonuclei density. In conclusion, long term AAS supplementation led to increases in lean leg mass, muscle fiber size and a parallel improvement in muscle strength, and all were dose-dependent. Administration of AAS may induce sustained

  16. Effects of long term supplementation of anabolic androgen steroids on human skeletal muscle.

    PubMed

    Yu, Ji-Guo; Bonnerud, Patrik; Eriksson, Anders; Stål, Per S; Tegner, Yelverton; Malm, Christer

    2014-01-01

    The effects of long-term (over several years) anabolic androgen steroids (AAS) administration on human skeletal muscle are still unclear. In this study, seventeen strength training athletes were recruited and individually interviewed regarding self-administration of banned substances. Ten subjects admitted having taken AAS or AAS derivatives for the past 5 to 15 years (Doped) and the dosage and type of banned substances were recorded. The remaining seven subjects testified to having never used any banned substances (Clean). For all subjects, maximal muscle strength and body composition were tested, and biopsies from the vastus lateralis muscle were obtained. Using histochemistry and immunohistochemistry (IHC), muscle biopsies were evaluated for morphology including fiber type composition, fiber size, capillary variables and myonuclei. Compared with the Clean athletes, the Doped athletes had significantly higher lean leg mass, capillary per fibre and myonuclei per fiber. In contrast, the Doped athletes had significantly lower absolute value in maximal squat force and relative values in maximal squat force (relative to lean body mass, to lean leg mass and to muscle fiber area). Using multivariate statistics, an orthogonal projection of latent structure discriminant analysis (OPLS-DA) model was established, in which the maximal squat force relative to muscle mass and the maximal squat force relative to fiber area, together with capillary density and nuclei density were the most important variables for separating Doped from the Clean athletes (regression  =  0.93 and prediction  =  0.92, p<0.0001). In Doped athletes, AAS dose-dependent increases were observed in lean body mass, muscle fiber area, capillary density and myonuclei density. In conclusion, long term AAS supplementation led to increases in lean leg mass, muscle fiber size and a parallel improvement in muscle strength, and all were dose-dependent. Administration of AAS may induce sustained

  17. PSA Response to Neoadjuvant Androgen Deprivation Therapy Is a Strong Independent Predictor of Survival in High-Risk Prostate Cancer in the Dose-Escalated Radiation Therapy Era

    SciTech Connect

    McGuire, Sean E.; Lee, Andrew K.; Cerne, Jasmina Z.; Munsell, Mark F.; Levy, Lawrence B.; Kudchadker, Rajat J.; Choi, Seungtaek L.; Nguyen, Quynh N.; Hoffman, Karen E.; Pugh, Thomas J.; Frank, Steven J.; Corn, Paul G.; Logothetis, Christopher J.; Kuban, Deborah A.

    2013-01-01

    Purpose: The aim of the study was to evaluate the prognostic value of prostate-specific antigen (PSA) response to neoadjuvant androgen deprivation therapy (ADT) prior to dose-escalated radiation therapy (RT) and long-term ADT in high-risk prostate cancer. Methods and Materials: We reviewed the charts of all patients diagnosed with high-risk prostate cancer and treated with a combination of long-term ADT (median, 24 months) and dose-escalated (median, 75.6 Gy) RT between 1990 and 2007. The associations among patient, tumor, and treatment characteristics with biochemical response to neoadjuvant ADT and their effects on failure-free survival (FFS), time to distant metastasis (TDM), prostate cancer-specific mortality (PCSM) and overall survival (OS) were examined. Results: A total of 196 patients met criteria for inclusion. Median follow-up time for patients alive at last contact was 7.0 years (range, 0.5-18.1 years). Multivariate analysis identified the pre-RT PSA concentration (<0.5 vs {>=}0.5 ng/mL) as a significant independent predictor of FFS (P=.021), TDM (P=.009), PCSM (P=.039), and OS (P=.037). On multivariate analysis, pretreatment PSA (iPSA) and African-American race were significantly associated with failure to achieve a pre-RT PSA of <0.5 ng/mL. Conclusions: For high-risk prostate cancer patients treated with long-term ADT and dose-escalated RT, a pre-RT PSA level {>=}0.5 ng/mL after neoadjuvant ADT predicts for worse survival measures. Both elevated iPSA and African-American race are associated with increased risk of having a pre-RT PSA level {>=}0.5 ng/mL. These patients should be considered for clinical trials that test newer, more potent androgen-depleting therapies such as abiraterone and MDV3100 in combination with radiation.

  18. Elevated hypothalamic aromatization at the onset of precocious puberty in transgenic female mice hypersecreting human chorionic gonadotropin: effect of androgens.

    PubMed

    Gonzalez, Betina; Ratner, Laura D; Scerbo, María J; Di Giorgio, Noelia P; Poutanen, Matti; Huhtaniemi, Ilpo T; Calandra, Ricardo S; Lux-Lantos, Victoria A R; Cambiasso, María J; Rulli, Susana B

    2014-06-01

    Transgenic female mice overexpressing the α- and β- subunits of human chorionic gonadotropin (hCGαβ+) exhibited precocious puberty, as evidenced by early vaginal opening. Chronically elevated hCG in 21-day-old hCGαβ+ females stimulated gonadal androgen production, which exerted negative feedback over the endogenous gonadotropin synthesis, and activated the hypothalamic GnRH pulsatility and gene expression. Transgenic females also exhibited elevated hypothalamic aromatization in the preoptic area (POA), which is the sexually-differentiated area that controls the LH surge in adulthood. Ovariectomy at 14 days of age was unable to rescue this phenotype. However, the blockade of androgen action by flutamide from postnatal day 6 onwards reduced the aromatase levels in the POA of hCGαβ+ females. Our results suggest that early exposure of females to androgen action during a critical period between postnatal days 6-14 induces sex-specific organizational changes of the brain, which affect the aromatase expression in the POA at the onset of precocious puberty.

  19. Disposition and metabolism of LY2452473, a selective androgen receptor modulator, in humans.

    PubMed

    Yi, Ping; Rehmel, Jessica Fayer; Cassidy, Kenneth; Hadden, Chad; Campanale, Kristina; Patel, Nita; Johnson, Jason

    2012-12-01

    The disposition and metabolism of isopropyl N-[(2S)-7-cyano-4-(2-pyridylmethyl)-2,3-dihydro-1H-cyclopenta[b]indol-2-yl]carbamate (LY2452473; a selective androgen receptor modulator) in humans was characterized after a single 15-mg (100 μCi) oral dose of [¹⁴C]LY2452473 to six healthy male subjects. LY2452473 was absorbed rapidly (time to reach maximum plasma concentration for both LY2452473 and total radioactivity was 2-3 h) and cleared slowly (plasma terminal t(½) of 27 h for LY2452473 and 51 h for the total radioactivity). LY2452473 and metabolites S5 (acetylamine) and S12 (hydroxylation on the cyclopentene) were major circulating entities in plasma, accounting for approximately 42, 21, and 35% of the total radioactivity exposure, respectively, as calculated from relative area under the concentration versus time curves from zero to 48 h derived from the plasma radiochromatograms. The radioactive dose was almost completely recovered after 312 h with 47.9% of the dose eliminated in urine and 46.6% in feces. Minimal LY2452473 was detected in excreta, indicating that metabolic clearance was the main route of elimination. Multiple metabolic pathways were observed with no single metabolic pathway accounting for more than 30% of the dose in excreta. Metabolite S10 (a diol across the cyclopenta-indole linkage) was the largest excretory metabolite (approximately 14% of the dose). S10 displayed interesting chemical and chromatographic properties, undergoing conversion to the corresponding epoxide under acidic conditions and conversion back to the diol under neutral conditions. An in vitro phenotyping approach indicated that CYP3A4 was the largest contributor to LY2452473 depletion. PMID:22961682

  20. Novel Nor-Homo- and Spiro-Oxetan- Steroids Target the Human Androgen Receptor and Act as Antiandrogens.

    PubMed

    Thiele, Marie; Rabe, Sebastian; Hessenkemper, Wiebke; Roell, Daniela; Bartsch, Sophie; Kraft, Florian; Abraham, Tsion E; Houtsmuller, Adriaan B; van Royen, Martin E; Giannis, Athanassios; Baniahmad, Aria

    2014-06-01

    The prostate adenocarcinoma is the cancer with the highest incidence for men in Western countries. Targeting the androgen receptor (AR) by antagonists is used as hormone therapy for prostate cancer (PCa), however, eventually therapy resistance occurs in most patients. In most of these cancer the AR signaling is active and thus AR remains an important drug target. Since many years we are characterizing novel chemical structural platforms to provide a broader possibility for compounds that bind to and act as AR antagonists. Here, we describe the chemical synthesis of a battery of novel steroidal derivatives as nor-homo-, spiro-oxolan- and spiro-oxetan- steroids. They modulate the transcriptional activity of the human AR. As AR antagonists, the spiro-oxetan- steroid derivatives seem to be the most potent steroid derivatives. They inhibit the transcriptional activity of both wild-type AR as well as the AR mutant T877A. In line with this, these compounds bind to the human AR and inhibit the proliferation of the human androgen-dependent growing PCa cell line LNCaP. Interestingly, the castration-resistant AR expressing human PC3-AR cells are also growth inhibited. On mechanistic level, fluorescence resonance energy transfer (FRET) assays with living cells indicate that the androgen-induced N/C terminal interaction of the AR is inhibited by the investigated compounds. Using fluorescence recovery after photobleaching (FRAP) assays in living cells suggest a higher mobility of the AR in the cell nuclei in the presence of spiro-oxetan- steroidal antagonists. Together, these findings suggest that spiro-oxetan- steroids are very useful as a chemical platform for novel AR antagonists.

  1. Control of adrenal androgen production.

    PubMed

    Odell, W D; Parker, L N

    The major adrenal androgens are dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS) and androstenedione (delta 4). Studies by Cutler et al in 1978 demonstrated that these androgens are detectable in blood of all domestic and laboratory animals studied, but that only 4 species show increase in one or more with sexual maturation: rabbit, dog, chimpanzee and man. Studies by Grover and Odell in 1975 show these androgens do not bind to the androgen receptor obtained from rat prostate and thus probably are androgens only by conversion to an active androgen in vivo. Thomas and Oake in 1974 showed human skin converted DHEA to testosterone. The control of adrenal androgen secretion is in part modulated by ACTH. However, other factors or hormones must exist also, for a variety of clinical observations show dissociation in adrenal androgen versus cortisol secretion. Other substances that have been said to be controllers of adrenal androgen secretion include estrogens, prolactin, growth hormone, gonadotropins and lipotropin. None of these appear to be the usual physiological modulator, although under some circumstances each may increase androgen production. Studies from our laboratory using in vivo experiments in the castrate dog and published in 1979 indicated that crude extracts of bovine pituitary contained a substance that either modified ACTH stimulation of adrenal androgen secretion, or stimulated secretion itself - Cortisol Androgen Stimulating Hormone. Parker et al in 1983 showed a 60,000 MW glycoprotein was extractable from human pituitaries, which stimulated DHA secretion by dispersed canine adrenal cells in vitro, but did not stimulate cortisol secretion. This material contained no ACTH by radioimmunoassay. In 1982 Brubaker et al reported a substance was also present in human fetal pituitaries, which stimulated DHA secretion, but did not effect cortisol. PMID:6100259

  2. 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

  3. The discovery of novel human androgen receptor antagonist chemotypes using a combined pharmacophore screening procedure.

    PubMed

    Voet, Arnout; Helsen, Christine; Zhang, Kam Y J; Claessens, Frank

    2013-04-01

    Unraveling the mechanisms involved in castration- and therapy-resistant prostate cancer has led to a renewed interest in androgen receptor (AR)-targeted therapeutics. Anti-androgens that block the activity of the AR therefore remain a valid therapeutic option. However, they must be more effective than, or display a distinct mechanism of action or binding mode from those of bicalutamide and hydroxyflutamide, which are currently in clinical use. For that reason, the second-generation anti-androgen MDV3100 was developed. MDV3100, however, shares its 4-cyano-3-(trifluoromethyl)phenyl group with bicalutamide and hydroxyflutamide required for binding to the AR. In this work, we used a combined strategy to find new antagonist structures distinct from the 4-cyano-3-(trifluoromethyl)phenyl group to avoid cross-resistance for these compounds and to find structures without agonist activity on mutant ARs (AR W741C and AR T877A). We found two novel chemotypes with AR-antagonistic activity (IC(50): 3-6 μM) by virtual screening and confirmed their biological activity in an androgen-responsive reporter assay. The design of our computational approach was validated by the observation of strongly decreased or absence of agonistic activity on the two mutant ARs. Further structural derivatization to optimize the potency of these compounds can render these chemotypes into very promising, alternative AR antagonists for prostate cancer therapy.

  4. 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

  5. Pomegranate Juice Metabolites, Ellagic Acid and Urolithin A, Synergistically Inhibit Androgen-Independent Prostate Cancer Cell Growth via Distinct Effects on Cell Cycle Control and Apoptosis

    PubMed Central

    Vicinanza, Roberto; Henning, Susanne M.; Heber, David

    2013-01-01

    Ellagitannins (ETs) from pomegranate juice (PJ) are bioactive polyphenols with chemopreventive potential against prostate cancer (PCa). ETs are not absorbed intact but are partially hydrolyzed in the gut to ellagic acid (EA). Colonic microflora can convert EA to urolithin A (UA), and EA and UA enter the circulation after PJ consumption. Here, we studied the effects of EA and UA on cell proliferation, cell cycle, and apoptosis in DU-145 and PC-3 androgen-independent PCa cells and whether combinations of EA and UA affected cell proliferation. EA demonstrated greater dose-dependent antiproliferative effects in both cell lines compared to UA. EA induced cell cycle arrest in S phase associated with decreased cyclin B1 and cyclin D1 levels. UA induced a G2/M arrest and increased cyclin B1 and cdc2 phosphorylation at tyrosine-15, suggesting inactivation of the cyclin B1/cdc2 kinase complex. EA induced apoptosis in both cell lines, while UA had a less pronounced proapoptotic effect only in DU-145. Cotreatment with low concentrations of EA and UA dramatically decreased cell proliferation, exhibiting synergism in PC-3 cells evaluated by isobolographic analysis and combination index. These data provide information on pomegranate metabolites for the prevention of PCa recurrence, supporting the role of gut flora-derived metabolites for cancer prevention. PMID:23710216

  6. ICRAC controls the rapid androgen response in human primary prostate epithelial cells and is altered in prostate cancer

    PubMed Central

    Holzmann, Christian; Kilch, Tatiana; Kappel, Sven; Armbrüster, Andrea; Jung, Volker; Stöckle, Michael; Bogeski, Ivan; Schwarz, Eva C.; Peinelt, Christine

    2013-01-01

    Labelled 5α-dihydrotestosterone (DHT) binding experiments have shown that expression levels of (yet unidentified) membrane androgen receptors (mAR) are elevated in prostate cancer and correlate with a negative prognosis. However, activation of these receptors which mediate a rapid androgen response can counteract several cancer hallmark functions such as unlimited proliferation, enhanced migration, adhesion and invasion and the inability to induce apoptosis. Here, we investigate the downstream signaling pathways of mAR and identify rapid DHT induced activation of store-operated Ca2+ entry (SOCE) in primary cultures of human prostate epithelial cells (hPEC) from non-tumorous tissue. Consequently, down-regulation of Orai1, the main molecular component of Ca2+ release-activated Ca2+ (CRAC) channels results in an almost complete loss of DHT induced SOCE. We demonstrate that this DHT induced Ca2+ influx via Orai1 is important for rapid androgen triggered prostate specific antigen (PSA) release. We furthermore identified alterations of the molecular components of CRAC channels in prostate cancer. Three lines of evidence indicate that prostate cancer cells down-regulate expression of the Orai1 homolog Orai3: First, Orai3 mRNA expression levels are significantly reduced in tumorous tissue when compared to non-tumorous tissue from prostate cancer patients. Second, mRNA expression levels of Orai3 are decreased in prostate cancer cell lines LNCaP and DU145 when compared to hPEC from healthy tissue. Third, the pharmacological profile of CRAC channels in prostate cancer cell lines and hPEC differ and siRNA based knock-down experiments indicate changed Orai3 levels are underlying the altered pharmacological profile. The cancer-specific composition and pharmacology of CRAC channels identifies CRAC channels as putative targets in prostate cancer therapy. PMID:24240085

  7. Late afternoon administration of melatonin is prosomatotrophic and exerts androgen independent effects on erythropoiesis in male house sparrow Passer domesticus.

    PubMed

    Pati, A K; Gupta, G

    1992-03-01

    In the third week of September 1989, birds were purchased locally and acclimated to their housing conditions in a room fully exposed to natural day length (average: 11.96 hr) and temperature (26 degrees +/- 2 degrees C) for 2 weeks. Birds were in the regressive phase of their annual gonadal cycle. In the first experiment 24 birds were selected randomly and were divided into 3 groups of 8 birds each. Initial body weight and bill color score were recorded. The birds of group-I and group-II were injected daily with 5 and 10 micrograms of melatonin in 0.1 ml of vehicle, respectively. The birds of group-III were injected with vehicle only and treated as control. Injections were given daily between 1700 and 1730 hrs over a period of 10 days. At the termination of the experiment, the birds were weighed, sacrificed, bill color scored, blood collected and immediately processed to determine the number of erythrocytes and hemoglobin concentration. The mean body weight loss amounted to 9.6% in vehicle-treated house sparrow. Birds receiving low and high doses of melatonin maintained their initial body weight. Melatonin significantly accelerated the rate of bleaching of bill color. Results clearly indicate that in house sparrow, melatonin produces prosomatotrophic and antigonadotrophic effects. The low dose of melatonin stimulated erythropoiesis significantly. In the second experiment, melatonin nullified the castration-induced decline in the number of circulating red cells. This clearly suggests that the influence of melatonin on erythropoietic machinery appears to be independent of testicular hormone(s).

  8. Cyclin D1 silencing suppresses tumorigenicity, impairs DNA double strand break repair and thus radiosensitizes androgen-independent prostate cancer cells to DNA damage

    PubMed Central

    Ju, Xiaoming; Vetuschi, Antonella; Sferra, Roberta; Casimiro, Mathew C.; Pompili, Simona; Festuccia, Claudio; Colapietro, Alessandro; Gaudio, Eugenio; Di Cesare, Ernesto; Tombolini, Vincenzo; Pestell, Richard G.

    2016-01-01

    Patients with hormone-resistant prostate cancer (PCa) have higher biochemical failure rates following radiation therapy (RT). Cyclin D1 deregulated expression in PCa is associated with a more aggressive disease: however its role in radioresistance has not been determined. Cyclin D1 levels in the androgen-independent PC3 and 22Rv1 PCa cells were stably inhibited by infecting with cyclin D1-shRNA. Tumorigenicity and radiosensitivity were investigated using in vitro and in vivo experimental assays. Cyclin D1 silencing interfered with PCa oncogenic phenotype by inducing growth arrest in the G1 phase of cell cycle and reducing soft agar colony formation, migration, invasion in vitro and tumor formation and neo-angiogenesis in vivo. Depletion of cyclin D1 significantly radiosensitizes PCa cells by increasing the RT-induced DNA damages by affecting the NHEJ and HR pathways responsible of the DNA double-strand break repair. Following treatment of cells with RT the abundance of a biomarker of DNA damage, γ-H2AX, was dramatically increased in sh-cyclin D1 treated cells compared to shRNA control. Concordant with these observations DNA-PKcs-activation and RAD51-accumulation, part of the DNA double-strand break repair machinery, were reduced in shRNA-cyclin D1 treated cells compared to shRNA control. We further demonstrate the physical interaction between CCND1 with activated-ATM, -DNA-PKcs and RAD51 is enhanced by RT. Finally, siRNA-mediated silencing experiments indicated DNA-PKcs and RAD51 are downstream targets of CCND1-mediated PCa cells radioresistance. In summary, these observations suggest that CCND1 is a key mediator of PCa radioresistance and could represent a potential target for radioresistant hormone-resistant PCa. PMID:26689991

  9. Suppression of rat and human androgen biosynthetic enzymes by apigenin: Possible use for the treatment of prostate cancer.

    PubMed

    Wang, Xiudi; Wang, Guimin; Li, Xiaoheng; Liu, Jianpeng; Hong, Tingting; Zhu, Qiqi; Huang, Ping; Ge, Ren-Shan

    2016-06-01

    Apigenin is a natural flavone. It has recently been used as a chemopreventive agent. It may also have some beneficial effects to treat prostate cancer by inhibiting androgen production. The objective of the present study was to investigate the effects of apigenin on the steroidogenesis of rat immature Leydig cells and some human testosterone biosynthetic enzyme activities. Rat immature Leydig cells were incubated for 3h with 100μM apigenin without (basal) or with 1ng/ml luteinizing hormone (LH), 10mM 8-bromoadenosine 3',5'-cyclic monophosphate (8BR), and 20μM of the following steroid substrates: 22R-hydroxychloesterol (22R), pregnenolone (P5), progesterone (P4), and androstenedione (D4). The medium levels of 5α-androstane-3α, 17β-diol (DIOL), the primary androgen produced by rat immature Leydig cells, were measured. Apigenin significantly inhibited basal, 8BR, 22R, PREG, P4, and D4 stimulated DIOL production in rat immature Leydig cells. Further study showed that apigenin inhibited rat 3β-hydroxysteroid dehydrogenase, 17α-hydroxylase/17, 20-lyase, and 17β-hydroxysteroid dehydrogenase 3 with IC50 values of 11.41±0.7, 8.98±0.10, and 9.37±0.07μM, respectively. Apigenin inhibited human 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase 3 with IC50 values of 2.17±0.04 and 1.31±0.09μM, respectively. Apigenin is a potent inhibitor of rat and human steroidogenic enzymes, being possible use for the treatment of prostate cancer. PMID:27102611

  10. Sex-dependent role of glucocorticoids and androgens in the pathophysiology of human obesity.

    PubMed

    Pasquali, R; Vicennati, V; Gambineri, A; Pagotto, U

    2008-12-01

    Obesity, particularly its abdominal phenotype, a harbinger of the metabolic syndrome, cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2D), is becoming one of the most significant public health problems worldwide. Among many other potential factors, derangement of multiple hormone systems have increasingly been considered for their potential importance in the pathophysiology of obesity and the metabolic syndrome, with particular reference to glucocorticoids and sex hormones. These systems have a fundamental and coordinating role in the physiology of intermediate metabolism and cardiovascular function, and in the response to acute and chronic stress challenge. Abdominal obesity is associated with a hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and impaired androgen balance, although these alterations differ according to sex. As there is also increasing evidence that there are many differences between the sexes in the susceptibility and development of obesity, T2D and CVDs, we support the hypothesis that alterations of the HPA axis and androgen balance may have an important function in this context. This is further supported by the fact that there are important differences between males and females in their ability to adapt to both internal and particularly to environmental (external) stressors. In addition, there is also evidence that, in both physiological and pathological conditions, a close cross talk exists between sex hormones and glucocorticoids at both neuroendocrine and peripheral level, again with different specificities according to sex.

  11. Differential Response to Abiraterone Acetate and Di-n-butyl Phthalate in an Androgen-Sensitive Human Fetal Testis Xenograft Bioassay

    PubMed Central

    Boekelheide, Kim

    2014-01-01

    In utero exposure to antiandrogenic xenobiotics such as di-n-butyl phthalate (DBP) has been linked to congenital defects of the male reproductive tract, including cryptorchidism and hypospadias, as well as later life effects such as testicular cancer and decreased sperm counts. Experimental evidence indicates that DBP has in utero antiandrogenic effects in the rat. However, it is unclear whether DBP has similar effects on androgen biosynthesis in human fetal testis. To address this issue, we developed a xenograft bioassay with multiple androgen-sensitive physiological endpoints, similar to the rodent Hershberger assay. Adult male athymic nude mice were castrated, and human fetal testis was xenografted into the renal subcapsular space. Hosts were treated with human chorionic gonadotropin for 4 weeks to stimulate testosterone production. During weeks 3 and 4, hosts were exposed to DBP or abiraterone acetate, a CYP17A1 inhibitor. Although abiraterone acetate (14 d, 75mg/kg/d po) dramatically reduced testosterone and the weights of androgen-sensitive host organs, DBP (14 d, 500mg/kg/d po) had no effect on androgenic endpoints. DBP did produce a near-significant trend toward increased multinucleated germ cells in the xenografts. Gene expression analysis showed that abiraterone decreased expression of genes related to transcription and cell differentiation while increasing expression of genes involved in epigenetic control of gene expression. DBP induced expression of oxidative stress response genes and altered expression of actin cytoskeleton genes. PMID:24284787

  12. Measurement of Androgen and Estrogen Concentrations in Cord Blood: Accuracy, Biological Interpretation, and Applications to Understanding Human Behavioral Development

    PubMed Central

    Hollier, Lauren P.; Keelan, Jeffrey A.; Hickey, Martha; Maybery, Murray T.; Whitehouse, Andrew J. O.

    2014-01-01

    Accurately measuring hormone exposure during prenatal life presents a methodological challenge and there is currently no “gold standard” approach. Ideally, circulating fetal hormone levels would be measured at repeated time points during pregnancy. However, it is not currently possible to obtain fetal blood samples without significant risk to the fetus, and therefore surrogate markers of fetal hormone levels must be utilized. Umbilical cord blood can be readily obtained at birth and largely reflects fetal circulation in late gestation. This review examines the accuracy and biological interpretation of the measurement of androgens and estrogens in cord blood. The use of cord blood hormones to understand and investigate human development is then discussed. PMID:24829559

  13. Development, validation and application of a stable isotope dilution liquid chromatography electrospray ionization/selected reaction monitoring/mass spectrometry (SID-LC/ESI/SRM/MS) method for quantification of keto-androgens in human serum.

    PubMed

    Tamae, Daniel; Byrns, Michael; Marck, Brett; Mostaghel, Elahe A; Nelson, Peter S; Lange, Paul; Lin, Daniel; Taplin, Mary-Ellen; Balk, Steven; Ellis, William; True, Larry; Vessella, Robert; Montgomery, Bruce; Blair, Ian A; Penning, Trevor M

    2013-11-01

    Prostate cancer is the most frequently diagnosed form of cancer in males in the United States. The disease is androgen driven and the use of orchiectomy or chemical castration, known as androgen deprivation therapy (ADT) has been employed for the treatment of advanced prostate cancer for over 70 years. Agents such as GnRH agonists and non-steroidal androgen receptor antagonists are routinely used in the clinic, but eventually relapse occurs due to the emergence of castration-resistant prostate cancer. With the appreciation that androgen signaling still persists in these patients and the development of new therapies such as abiraterone and enzalutamide that further suppresses androgen synthesis or signaling, there is a renewed need for sensitive and specific methods to quantify androgen precursor and metabolite levels to assess drug efficacy. We describe the development, validation and application of a stable isotope dilution liquid chromatography electrospray ionization selected reaction monitoring mass spectrometry (SID-LC/ESI/SRM/MS) method for quantification of serum keto-androgens and their sulfate and glucuronide conjugates using Girard-T oxime derivatives. The method is robust down to 0.2-4pg on column, depending on the androgen metabolite quantified, and can also quantify dehydroepiandrosterone sulfate (DHEA-S) in only 1μL of serum. The clinical utility of this method was demonstrated by analyzing serum androgens from patients enrolled in a clinical trial assessing combinations of pharmacological agents to maximally suppress gonadal and adrenal androgens (Targeted Androgen Pathway Suppression, TAPS clinical trial). The method was validated by correlating the results obtained with a hydroxylamine derivatization procedure coupled with tandem mass spectrometry using selected reaction monitoring that was conducted in an independent laboratory.

  14. Reinforcing aspects of androgens.

    PubMed

    Wood, Ruth I

    2004-11-15

    Are androgens reinforcing? Androgenic-anabolic steroids (AAS) are drugs of abuse. They are taken in large quantities by athletes and others to increase performance, often with negative long-term health consequences. As a result, in 1991, testosterone was declared a controlled substance. Recently, Brower [K.J. Brower, Anabolic steroid abuse and dependence. Curr. Psychiatry Rep. 4 (2002) 377-387.] proposed a two-stage model of AAS dependence. Users initiate steroid use for their anabolic effects on muscle growth. With continued exposure, dependence on the psychoactive effects of AAS develops. However, it is difficult in humans to separate direct psychoactive effects of AAS from the user's psychological dependence on the anabolic effects of AAS. Thus, studies in laboratory animals are useful to explore androgen reinforcement. Testosterone induces a conditioned place preference in rats and mice, and is voluntarily consumed through oral, intravenous, and intracerebroventricular self-administration in hamsters. Active, gonad-intact male and female hamsters will deliver 1 microg/microl testosterone into the lateral ventricles. Indeed, some individuals self-administer testosterone intracerebroventricularly to the point of death. Male rats develop a conditioned place preference to testosterone injections into the nucleus accumbens, an effect blocked by dopamine receptor antagonists. These data suggest that androgen reinforcement is mediated by the brain. Moreover, testosterone appears to act through the mesolimbic dopamine system, a common substrate for drugs of abuse. Nonetheless, androgen reinforcement is not comparable to that of cocaine or heroin. Instead, testosterone resembles other mild reinforcers, such as caffeine, nicotine, or benzodiazepines. The potential for androgen addiction remains to be determined.

  15. Androgen regulation of the human FERM domain encoding gene EHM2 in a cell model of steroid-induced differentiation

    PubMed Central

    Chauhan, Sanjay; Pandey, Ritu; Way, Jeffrey F.; Sroka, Thomas C.; Demetriou, Manolis C.; Kunz, Susan; Cress, Anne E.; Mount, David W.; Miesfeld, Roger L.

    2009-01-01

    We have developed a cell model to investigate steroid control of differentiation using a subline of HT1080 cells (HT-AR1) that have been engineered to express the human androgen receptor. Dihydrotestosterone (DHT) treatment of HT-AR1 cells induced growth arrest and cytoskeletal reorganization that was associated with the expression of fibronectin and the neuroendocrine markers chromogranin A and neuron-specific enolase. Expression profiling analysis identified the human FERM domain-encoding gene EHM2 as uniquely induced in HT-AR1 cells as compared to 16 other FERM domain containing genes. Since FERM domain proteins control cytoskeletal functions in differentiating cells, and the human EHM2 gene has not been characterized, we investigated EHM2 steroid-regulation, genomic organization, and sequence conservation. We found that DHT, but not dexamethasone, induced the expression of a 3.8 kb transcript in HT-AR1 cells encoding a 504 amino acid protein, and moreover, that human brain tissue contains a 5.8 kb transcript encoding a 913 amino acid isoform. Construction of an unrooted phylogenetic tree using 98 FERM domain proteins revealed that the human EHM2 gene is a member of a distinct subfamily consisting of nine members, all of which contain a highly conserved 325 amino acid FERM domain. PMID:14521927

  16. Sexual dimorphism in neuronal number of the posterodorsal medial amygdala is independent of circulating androgens and regional volume in adult rats.

    PubMed

    Morris, John A; Jordan, Cynthia L; Breedlove, S Marc

    2008-02-10

    The posterodorsal medial amygdala (MePD) in rodents integrates olfactory and pheromonal information, which, coupled with the appropriate hormonal signals, may facilitate or repress reproductive behavior in adulthood. MePD volume and neuronal soma size are greater in male rats than in females, and these sexual dimorphisms are maintained by adult circulating hormone levels. Castration of adult males causes these measures to shrink to the size seen in females 4 weeks later, whereas testosterone treatment of adult females for 4 weeks enlarges these measures to the size of males. We used stereological methods to count the number of cells in the MePD and found that, in addition to the sex difference in regional volume and soma size, males also have more MePD neurons than do females, yet these numbers are unaffected by the presence or absence of androgen in adults of either sex. Males also have more glial cells than do females, but, in contrast to the effects on neuronal number, the number of glial cells is affected by androgen in the right MePD of both sexes and, therefore, may contribute to regional volume changes in adulthood in that hemisphere. Thus, regional volume, neuronal size, and glial numbers vary in the MePD of adult rats in response to circulating androgens, but neuronal number does not. These results suggest that the sex difference in neuronal number in the rat MePD may be "organized" by androgens prior to adulthood, whereas regional volume, neuronal size, and glial numbers can be altered by androgens in adulthood. PMID:18076082

  17. Human sex hormone-binding globulin binding affinities of 125 structurally diverse chemicals and comparison with their binding to androgen receptor, estrogen receptor, and α-fetoprotein.

    PubMed

    Hong, Huixiao; Branham, William S; Ng, Hui Wen; Moland, Carrie L; Dial, Stacey L; Fang, Hong; Perkins, Roger; Sheehan, Daniel; Tong, Weida

    2015-02-01

    One endocrine disruption mechanism is through binding to nuclear receptors such as the androgen receptor (AR) and estrogen receptor (ER) in target cells. The concentration of a chemical in serum is important for its entry into the target cells to bind the receptors, which is regulated by the serum proteins. Human sex hormone-binding globulin (SHBG) is the major transport protein in serum that can bind androgens and estrogens and thus change a chemical's availability to enter the target cells. Sequestration of an androgen or estrogen in the serum can alter the chemical elicited AR- and ER-mediated responses. To better understand the chemical-induced endocrine activity, we developed a competitive binding assay using human pregnancy plasma and measured the binding to the human SHBG for 125 structurally diverse chemicals, most of which were known to bind AR and ER. Eighty seven chemicals were able to bind the human SHBG in the assay, whereas 38 chemicals were nonbinders. Binding data for human SHBG are compared with that for rat α-fetoprotein, ER and AR. Knowing the binding profiles between serum and nuclear receptors will improve assessment of a chemical's potential for endocrine disruption. The SHBG binding data reported here represent the largest data set of structurally diverse chemicals tested for human SHBG binding. Utilization of the SHBG binding data with AR and ER binding data could enable better evaluation of endocrine disrupting potential of chemicals through AR- and ER-mediated responses since sequestration in serum could be considered.

  18. Aromatization of 15 alpha and 16 alpha hydroxylated androgens in the human placental using [1,2-3H]-substrates.

    PubMed

    Cantineau, R; Kremers, P; De Graeve, J; Gielen, J E; Lambotte, R

    1982-02-01

    This in vitro study reports data on the aromatization of [1,2-3H]-C19 steroids in the human term placenta [androstenedione (III), testosterone (IV), 15 alpha-hydroxy-androstenedione (V), 15 alpha-hydroxy-testosterone (VI), 16 alpha-hydroxy-androstenedione (VII)]. The hydroxylated androgens were microbiologically synthesized from commercially radiolabelled [1,2-3H]-androstenedione and testosterone. Androstenedione and testosterone were good substrates for the human placental aromatase (low Km values, high Vmax); they strongly inhibited the 15 and 16 hydroxylated androgens aromatizations. On the other hand, these hydroxylated compounds acted as poor substrates and were only non-competitive inhibitors of the androstenedione and testosterone aromatizations. However, 15 alpha-hydroxy-androstenedione could not be disregarded as a potential precursor of 15 alpha-hydroxylated estrogens in the human placenta. PMID:7078154

  19. Independence.

    ERIC Educational Resources Information Center

    Stephenson, Margaret E.

    2000-01-01

    Discusses the four planes of development and the periods of creation and crystallization within each plane. Identifies the type of independence that should be achieved by the end of the first two planes of development. Maintains that it is through individual work on the environment that one achieves independence. (KB)

  20. Effect of androgen deficiency on the human meibomian gland and ocular surface.

    PubMed

    Krenzer, K L; Dana, M R; Ullman, M D; Cermak, J M; Tolls, D B; Evans, J E; Sullivan, D A

    2000-12-01

    The purpose of this study was to determine whether the chronic use of antiandrogen medications leads to meibomian gland dysfunction, altered lipid profiles in meibomian gland secretions, decreased tear film stability, and evaporative dry eye. Subjects taking antiandrogen therapy for prostatic indications, as well as age-related controls, were asked to complete a questionnaire that assessed dry eye symptoms and then were given a complete anterior segment examination. Moreover, meibomian gland secretions were obtained from each eye and analyzed by high-performance liquid chromatography/mass spectrometry for the relative content of cholesterol, cholesterol esters, wax esters, diglycerides, triglycerides, and specific molecular species in the diglyceride fraction. Our results demonstrate that patients taking antiandrogen treatment, compared with age-related controls, had a: 1) significant increase in the frequency of appearance of tear film debris, an abnormal tear film meniscus, irregular posterior lid margins, conjunctival tarsal injection, and orifice metaplasia of the meibomian glands; 2) significant increase in the degree of ocular surface vital dye staining; 3) significant decrease in the tear film breakup time and quality of meibomian gland secretions; and 4) significant increase in the frequency of light sensitivity, painful eyes, and blurred vision. In addition, the use of antiandrogen pharmaceuticals was associated with significant changes in the relative amounts of lipids in meibomian gland secretions. Our findings indicate that chronic androgen deficiency is associated with meibomian gland dysfunction and dry eye.

  1. Human heterochromatin protein 1 isoforms regulate androgen receptor signaling in prostate cancer.

    PubMed

    Itsumi, Momoe; Shiota, Masaki; Yokomizo, Akira; Kashiwagi, Eiji; Takeuchi, Ario; Tatsugami, Katsunori; Inokuchi, Junichi; Song, Yoohyun; Uchiumi, Takeshi; Naito, Seiji

    2013-06-01

    Androgen receptor (AR) signaling is critical for the tumorigenesis and development of prostate cancer, as well as the progression to castration-resistant prostate cancer. We previously showed that the heterochromatin protein 1 (HP1) β isoform plays a critical role in transactivation of AR signaling as an AR coactivator that promotes prostate cancer cell proliferation. However, the roles of other HP1 isoforms, HP1α and HP1γ, in AR expression and prostate cancer remain unclear. Here, we found that knockdown of HP1γ, but not HP1α, reduced AR expression and cell proliferation by inducing cell cycle arrest at G1 phase in LNCaP cells. Conversely, overexpression of full-length HP1α and its C-terminal deletion mutant increased AR expression and cell growth, whereas overexpression of HP1γ had no effect. Similarly, HP1α overexpression promoted 22Rv1 cell growth, whereas HP1γ knockdown reduced the proliferation of CxR cells, a castration-resistant LNCaP derivative. Taken together, HP1 isoforms distinctly augment AR signaling and cell growth in prostate cancer. Therefore, silencing of HP1β and HP1γ may be a promising therapeutic strategy for treatment of prostate cancer.

  2. Longitudinally mapping the influence of sex and androgen signaling on the dynamics of human cortical maturation in adolescence

    PubMed Central

    Raznahan, Armin; Lee, Yohan; Stidd, Reva; Long, Robert; Greenstein, Dede; Clasen, Liv; Addington, Anjene; Gogtay, Nitin; Rapoport, Judith L.; Giedd, Jay N.

    2010-01-01

    Humans have systematic sex differences in brain-related behavior, cognition, and pattern of mental illness risk. Many of these differences emerge during adolescence, a developmental period of intense neurostructural and endocrine change. Here, by creating “movies” of sexually dimorphic brain development using longitudinal in vivo structural neuroimaging, we show regionally specific sex differences in development of the cerebral cortex during adolescence. Within cortical subsystems known to underpin domains of cognitive behavioral sex difference, structural change is faster in the sex that tends to perform less well within the domain in question. By stratifying participants through molecular analysis of the androgen receptor gene, we show that possession of an allele conferring more efficient functioning of this sex steroid receptor is associated with “masculinization” of adolescent cortical maturation. Our findings extend models first established in rodents, and suggest that in humans too, sex and sex steroids shape brain development in a spatiotemporally specific manner, within neural systems known to underpin sexually dimorphic behaviors. PMID:20841422

  3. Tumoristatic effects of endostatin in prostate cancer is dependent on androgen receptor status

    PubMed Central

    Isayeva, Tatyana; Moore, Lakisha D.; Chanda, Diptiman; Chen, Dongquan; Ponnazhagan, Selvarangan

    2016-01-01

    Background Although antiangiogenic therapy is a promising new line of therapy for prostate cancer, we recently reported that stable expression of endostatin arrested the progression of prostate cancer to poorly differentiated state and distant metastasis in TRAMP mice. However, the same therapy failed to provide any benefit when given either during or after the onset of metastatic switch. The present study determined the possible mechanisms behind the selective advantage of endostatin therapy in early stage disease. Methods Angiogenesis-related gene expression analysis was performed to identify target genes and molecular pathways involved in the therapy effects. Based on the results from in vivo studies, and recapitulation of the in vivo data in vitro using tumorigenic and non-tumorigenic human prostate cancer cells that are either androgen-sensitive or androgen-independent, analyses of possible mechanisms of the selective advantage of early treatment were performed using assays for cell proliferation, apoptosis, migration and cell signaling. The identified mechanisms were further confirmed in vivo. Results Results indicated that cells with high androgen receptor (AR) expression were more sensitive to endostatin treatment than androgen-independent cells with low or no AR expression. Endostatin was found to significantly downregulate the expression of growth factors, receptor tyrosine kinases, proteases, and AR both in vitro and in vivo only when the cells express high levels of AR. Cell proliferation was not influenced by endostatin treatment but migration was significantly affected only in androgen-sensitive cells. Targeted downregulation of AR prior to endostatin treatment in androgen sensitive cells and overexpression of AR in androgen independent cells indicated that the effect of endostatin via AR downregulation is mediated by a non-genotropic mechanism on Ras and RhoA pathways, and independently of AR on MAPK/ERK pathway. Conclusions These data indicate that

  4. Interactions of androgens, green tea catechins and the antiandrogen flutamide with the external glucose-binding site of the human erythrocyte glucose transporter GLUT1.

    PubMed

    Naftalin, Richard J; Afzal, Iram; Cunningham, Philip; Halai, Mansur; Ross, Clare; Salleh, Naguib; Milligan, Stuart R

    2003-10-01

    This study investigates the effects of androgens, the antiandrogen flutamide and green tea catechins on glucose transport inhibition in human erythrocytes. These effects may relate to the antidiabetogenic effects of green tea. Testosterone, 4-androstene-3,17-dione, dehydroepiandrosterone (DHEA) and DHEA-3-acetate inhibit glucose exit from human erythrocytes with half-maximal inhibitions (Ki) of 39.2+/-8.9, 29.6+/-3.7, 48.1+/-10.2 and 4.8+/-0.98 microM, respectively. The antiandrogen flutamide competitively relieves these inhibitions and of phloretin. Dehydrotestosterone has no effect on glucose transport, indicating the differences between androgen interaction with GLUT1 and human androgen receptor (hAR). Green tea catechins also inhibit glucose exit from erythrocytes. Epicatechin 3-gallate (ECG) has a Ki ECG of 0.14+/-0.01 microM, and epigallocatechin 3-gallate (EGCG) has a Ki EGCG of 0.97+/-0.13 microM. Flutamide reverses these effects. Androgen-screening tests show that the green tea catechins do not act genomically. The high affinities of ECG and EGCG for GLUT1 indicate that this might be their physiological site of action. There are sequence homologies between GLUT1 and the ligand-binding domain (LBD) of hAR containing the amino-acid triads Arg 126, Thr 30 and Asn 288, and Arg 126, Thr 30 and Asn 29, with similar 3D topology to the polar groups binding 3-keto and 17-beta OH steroid groups in hAR LBD. These triads are appropriately sited for competitive inhibition of glucose import at the external opening of the hydrophilic pore traversing GLUT1.

  5. Sex differences in androgen receptors of the human mamillary bodies are related to endocrine status rather than to sexual orientation or transsexuality.

    PubMed

    Kruijver, F P; Fernández-Guasti, A; Fodor, M; Kraan, E M; Swaab, D F

    2001-02-01

    In a previous study we found androgen receptor (AR) sex differences in several regions throughout the human hypothalamus. Generally, men had stronger nuclear AR immunoreactivity (AR-ir) than women. The strongest nuclear labeling was found in the caudal hypothalamus in the mamillary body complex (MBC), which is known to be involved in aspects of cognition and sexual behavior. The present study was carried out to investigate whether the sex difference in AR-ir of the MBC is related to sexual orientation or gender identity (i.e. the feeling of being male or female) or to circulating levels of androgens, as nuclear AR-ir is known to be up-regulated by androgens. Therefore, we studied the MBC in postmortem brain material from the following groups: young heterosexual men, young homosexual men, aged heterosexual castrated and noncastrated men, castrated and noncastrated transsexuals, young heterosexual women, and a young virilized woman. Nuclear AR-ir did not differ significantly between heterosexual and homosexual men, but was significantly stronger than that in women. A female-like pattern of AR-ir (i.e. no to weak nuclear staining) was observed in 26- to 53-yr-old castrated male-to-female transsexuals and in old castrated and noncastrated men, 67--87 yr of age. In analogy with animal studies showing strong activational effects of androgens on nuclear AR-ir, the present data suggest that nuclear AR-ir in the human MBC is dependent on the presence or absence of circulating levels of androgen. The group data were, moreover, supported by the fact that a male-like AR-ir (i.e. intense nuclear AR-ir) was found in a 36-yr-old bisexual noncastrated male-to-female transsexual and in a heterosexual virilized woman, 46 yr of age, with high levels of circulating testosterone. In conclusion, the sexually dimorphic AR-ir in the MBC seemed to be clearly related to circulating levels of androgens and not to sexual orientation or gender identity. The functional implications of these

  6. An Sp1 Modulated Regulatory Region Unique to Higher Primates Regulates Human Androgen Receptor Promoter Activity in Prostate Cancer Cells.

    PubMed

    Hay, Colin W; Hunter, Irene; MacKenzie, Alasdair; McEwan, Iain J

    2015-01-01

    Androgen receptor (AR) mediated signalling is necessary for normal development of the prostate gland and also drives prostate cancer (PCa) cell growth and survival, with many studies showing a correlation between increased receptor levels and therapy resistance with progression to fatal castrate recurrent PCa (CRPC). Although it has been held for some time that the transcription factor Sp1 is the main stimulator of AR gene transcription, comprehensive knowledge of the regulation of the AR gene remains incomplete. Here we describe and characterise in detail two novel active regulatory elements in the 5'UTR of the human AR gene. Both of these elements contain overlapping binding sites for the positive transcription factor Sp1 and the repressor protein pur-α. Aberrant cell signalling is characteristic of PCa and the transcriptional activity of the AR promoter in PCa cells is dependent upon the relative amounts of the two transcription factors. Together with our corroboration of the dominant role of Sp1, the findings support the rationale of targeting this transcription factor to inhibit tumour progression. This should be of particular therapeutic relevance in CRPC where the levels of the repressor pur-α are reduced. PMID:26448047

  7. Mitochondrial DNA determines androgen dependence in prostate cancer cell lines

    PubMed Central

    Higuchi, M; Kudo, T; Suzuki, S; Evans, TT; Sasaki, R; Wada, Y; Shirakawa, T; Sawyer, JR; Gotoh, A

    2008-01-01

    Prostate cancer progresses from an androgen-dependent to androgen-independent stage after androgen ablation therapy. Mitochondrial DNA plays a role in cell death and metastatic competence. Further, heteroplasmic large-deletion mitochondrial DNA is verycommon in prostate cancer. To investigate the role of mitochondrial DNA in androgen dependence of prostate cancers, we tested the changes of normal and deleted mitochondrial DNA in accordance with the progression of prostate cancer. We demonstrated that the androgen-independent cell line C4-2, established byinoculation of the androgen-dependent LNCaP cell line into castrated mice, has a greatlyreduced amount of normal mitochondrial DNA and an accumulation of large-deletion DNA. Strikingly, the depletion of mitochondrial DNA from androgen-dependent LNCaP resulted in a loss of androgen dependence. Reconstitution of normal mitochondrial DNA to the mitochondrial DNA-depleted clone restored androgen dependence. These results indicate that mitochondrial DNA determines androgen dependence of prostate cancer cell lines. Further, mitochondrial DNA-deficient cells formed tumors in castrated athymic mice, whereas LNCaP did not. The accumulation of large deletion and depletion of mitochondrial DNA maythus playa role in the development of androgen independence, leading to progression of prostate cancers. PMID:16278679

  8. Effects of 2,4-D and DCP on the DHT-induced androgenic action in human prostate cancer cells.

    PubMed

    Kim, Hyun-Jung; Park, Young In; Dong, Mi-Sook

    2005-11-01

    2,4-Dichlorophenoxyacetic acid (2,4-D) and its metabolite 2,4-dichlorophenol (DCP) are used extensively in agriculture as herbicides, and are suspected of potential endocrine disruptor activity. In a previous study, we showed that these compounds exhibited synergistic androgenic effects by co-treatment with testosterone in the Hershberger assay. To elucidate the mechanisms of the synergistic effects of these compounds on the androgenicity of testosterone, the androgenic action of 2,4-D and DCP was characterized using a mammalian detection system in prostate cancer cell lines. In in vitro assay systems, while 2,4-D or DCP alone did not show androgenic activity, 2,4-D or DCP with 5alpha-dihydroxytestosterone (DHT) exhibited synergistic androgenic activities. Co-treatment of 10 nM 2,4-D or DCP with 10 nM DHT was shown to stimulate the cell proliferation by 1.6-fold, compared to 10 nM DHT alone. In addition, in transient transfection assays, androgen-induced transactivation was also increased to a maximum of 32-fold or 1.28-fold by co-treatment of 2,4-D or DCP with DHT, respectively. However, 2,4-D and DCP exerted no effects on either mRNA or protein levels of AR. In a competitive AR binding assay, 2,4-D and DCP inhibited androgen binding to AR, up to 50% at concentrations of approximately 0.5 microM for both compounds. The nuclear translocation of green fluorescent protein-AR fusion protein in the presence of DHT was promoted as the result of the addition of 2,4-D and DCP. Collectively, these results that 2,4-D and DCP enhanced DHT-induced AR transcriptional activity might be attributable, at least in part, to the promotion of AR nuclear translocation.

  9. 3,3'-Diindolylmethane (DIM) and its ring-substituted halogenated analogs (ring-DIMs) induce differential mechanisms of survival and death in androgen-dependent and -independent prostate cancer cells.

    PubMed

    Goldberg, Alexander A; Draz, Hossam; Montes-Grajales, Diana; Olivero-Verbél, Jesus; Safe, Stephen H; Sanderson, J Thomas

    2015-05-01

    We recently reported that novel ring-substituted analogs of 3,3'-diindolylmethane (ring-DIMs) induce apoptosis and necrosis in androgen-dependent and -independent prostate cancer cells. In this paper, we have focused on the mechanism(s) associated with ring-DIM-mediated cell death, and on identifying the specific intracellular target(s) of these compounds. The 4,4'- and 7,7'-dichloroDIMs and 4,4'- and 7,7'-dibromoDIMs induced the death of LNCaP, C42B and DU145 prostate cancer cells, but not that of immortalized normal human prostate epithelial (RWPE-1) cells. Ring-DIMs caused the early loss of mitochondrial membrane potential (MMP) and decreased mitochondrial ATP generation in prostate cancer cells. Cyclosporin A, an inhibitor of the mitochondrial permeability transition pore, inhibited ring-DIM-mediated cell death, and salubrinal, an inhibitor of ER stress, inhibited cell death mediated only by 4,4'-dihaloDIMs. We found that although salubrinal did not inhibit the onset of ER stress, it prevented 4,4'-dibromoDIM mediated loss of MMP. Salubrinal potentiated cell death in response to 7,7'-dihaloDIMs and DIM, and this effect concurred with increased loss of MMP. Using in silico 3-D docking affinity analysis, we identified Ca2+/calmodulin-dependent kinase II (CaMKII) as a potential direct target for the most toxic ring-DIM, 4,4'-dibromoDIM. An inhibitor of CaMKII, KN93, but not its inactive analog KN92, abrogated cell death mediated by 4,4'-dibromoDIM. The ring-DIMs induced ER stress and autophagy, but these processes were not necessary for ring-DIM-mediated cell death. Inhibition of autophagy with bafilomycin A1, 3-methyladenine or by LC3B gene silencing sensitized LNCaP and C42B, but not ATG5-deficient DU145 cells to ring-DIM- and DIM-mediated cell death. We propose that autophagy induced by the ring-DIMs and DIM has a cytoprotective function in prostate cancer cells. PMID:26124925

  10. 3,3′-Diindolylmethane (DIM) and its ring-substituted halogenated analogs (ring-DIMs) induce differential mechanisms of survival and death in androgen-dependent and –independent prostate cancer cells

    PubMed Central

    Montes-Grajales, Diana; Olivero-Verbél, Jesus; Safe, Stephen H.; Sanderson, J. Thomas

    2015-01-01

    We recently reported that novel ring-substituted analogs of 3,3′-diindolylmethane (ring-DIMs) induce apoptosis and necrosis in androgen-dependent and –independent prostate cancer cells. In this paper, we have focused on the mechanism(s) associated with ring-DIM-mediated cell death, and on identifying the specific intracellular target(s) of these compounds. The 4,4′- and 7,7′-dichloroDIMs and 4,4′- and 7,7′-dibromoDIMs induced the death of LNCaP, C42B and DU145 prostate cancer cells, but not that of immortalized normal human prostate epithelial (RWPE-1) cells. Ring-DIMs caused the early loss of mitochondrial membrane potential (MMP) and decreased mitochondrial ATP generation in prostate cancer cells. Cyclosporin A, an inhibitor of the mitochondrial permeability transition pore, inhibited ring-DIM-mediated cell death, and salubrinal, an inhibitor of ER stress, inhibited cell death mediated only by 4,4′-dihaloDIMs. We found that although salubrinal did not inhibit the onset of ER stress, it prevented 4,4′-dibromoDIM mediated loss of MMP. Salubrinal potentiated cell death in response to 7,7′-dihaloDIMs and DIM, and this effect concurred with increased loss of MMP. Using in silico 3-D docking affinity analysis, we identified Ca2+/calmodulin-dependent kinase II (CaMKII) as a potential direct target for the most toxic ring-DIM, 4,4′-dibromoDIM. An inhibitor of CaMKII, KN93, but not its inactive analog KN92, abrogated cell death mediated by 4,4′-dibromoDIM. The ring-DIMs induced ER stress and autophagy, but these processes were not necessary for ring-DIM-mediated cell death. Inhibition of autophagy with bafilomycin A1, 3-methyladenine or by LC3B gene silencing sensitized LNCaP and C42B, but not ATG5-deficient DU145 cells to ring-DIM- and DIM-mediated cell death. We propose that autophagy induced by the ring-DIMs and DIM has a cytoprotective function in prostate cancer cells. PMID:26124925

  11. Proteasomal degradation of sphingosine kinase 1 and inhibition of dihydroceramide desaturase by the sphingosine kinase inhibitors, SKi or ABC294640, induces growth arrest in androgen-independent LNCaP-AI prostate cancer cells

    PubMed Central

    McNaughton, Melissa; Pitman, Melissa; Pitson, Stuart M.; Pyne, Nigel J.; Pyne, Susan

    2016-01-01

    Sphingosine kinases (two isoforms termed SK1 and SK2) catalyse the formation of the bioactive lipid sphingosine 1-phosphate. We demonstrate here that the SK2 inhibitor, ABC294640 (3-(4-chlorophenyl)-adamantane-1-carboxylic acid (pyridin-4-ylmethyl)amide) or the SK1/SK2 inhibitor, SKi (2-(p-hydroxyanilino)-4-(p-chlorophenyl)thiazole)) induce the proteasomal degradation of SK1a (Mr = 42 kDa) and inhibit DNA synthesis in androgen-independent LNCaP-AI prostate cancer cells. These effects are recapitulated by the dihydroceramide desaturase (Des1) inhibitor, fenretinide. Moreover, SKi or ABC294640 reduce Des1 activity in Jurkat cells and ABC294640 induces the proteasomal degradation of Des1 (Mr = 38 kDa) in LNCaP-AI prostate cancer cells. Furthermore, SKi or ABC294640 or fenretinide increase the expression of the senescence markers, p53 and p21 in LNCaP-AI prostate cancer cells. The siRNA knockdown of SK1 or SK2 failed to increase p53 and p21 expression, but the former did reduce DNA synthesis in LNCaP-AI prostate cancer cells. Moreover, N-acetylcysteine (reactive oxygen species scavenger) blocked the SK inhibitor-induced increase in p21 and p53 expression but had no effect on the proteasomal degradation of SK1a. In addition, siRNA knockdown of Des1 increased p53 expression while a combination of Des1/SK1 siRNA increased the expression of p21. Therefore, Des1 and SK1 participate in regulating LNCaP-AI prostate cancer cell growth and this involves p53/p21-dependent and -independent pathways. Therefore, we propose targeting androgen-independent prostate cancer cells with compounds that affect Des1/SK1 to modulate both de novo and sphingolipid rheostat pathways in order to induce growth arrest. PMID:26934645

  12. Proteasomal degradation of sphingosine kinase 1 and inhibition of dihydroceramide desaturase by the sphingosine kinase inhibitors, SKi or ABC294640, induces growth arrest in androgen-independent LNCaP-AI prostate cancer cells.

    PubMed

    McNaughton, Melissa; Pitman, Melissa; Pitson, Stuart M; Pyne, Nigel J; Pyne, Susan

    2016-03-29

    Sphingosine kinases (two isoforms termed SK1 and SK2) catalyse the formation of the bioactive lipid sphingosine 1-phosphate. We demonstrate here that the SK2 inhibitor, ABC294640 (3-(4-chlorophenyl)-adamantane-1-carboxylic acid (pyridin-4-ylmethyl)amide) or the SK1/SK2 inhibitor, SKi (2-(p-hydroxyanilino)-4-(p-chlorophenyl)thiazole)) induce the proteasomal degradation of SK1a (Mr = 42 kDa) and inhibit DNA synthesis in androgen-independent LNCaP-AI prostate cancer cells. These effects are recapitulated by the dihydroceramide desaturase (Des1) inhibitor, fenretinide. Moreover, SKi or ABC294640 reduce Des1 activity in Jurkat cells and ABC294640 induces the proteasomal degradation of Des1 (Mr = 38 kDa) in LNCaP-AI prostate cancer cells. Furthermore, SKi or ABC294640 or fenretinide increase the expression of the senescence markers, p53 and p21 in LNCaP-AI prostate cancer cells. The siRNA knockdown of SK1 or SK2 failed to increase p53 and p21 expression, but the former did reduce DNA synthesis in LNCaP-AI prostate cancer cells. Moreover, N-acetylcysteine (reactive oxygen species scavenger) blocked the SK inhibitor-induced increase in p21 and p53 expression but had no effect on the proteasomal degradation of SK1a. In addition, siRNA knockdown of Des1 increased p53 expression while a combination of Des1/SK1 siRNA increased the expression of p21. Therefore, Des1 and SK1 participate in regulating LNCaP-AI prostate cancer cell growth and this involves p53/p21-dependent and -independent pathways. Therefore, we propose targeting androgen-independent prostate cancer cells with compounds that affect Des1/SK1 to modulate both de novo and sphingolipid rheostat pathways in order to induce growth arrest.

  13. Differential splicing of human androgen receptor pre-mRNA in X-linked reifenstein syndrome, because of a deletion involving a putative branch site

    SciTech Connect

    Ris-Stalpers, C.; Verleun-Mooijman, M.C.T.; Blaeij, T.J.P. de; Brinkmann, A.O.; Degenhart, H.J.; Trapman, J. )

    1994-04-01

    The analysis of the androgen receptor (AR) gene, mRNA, and protein in a subject with X-linked Reifenstein syndrome (partial androgen insensitivity) is reported. The presence of two mature AR transcripts in genital skin fibroblasts of the patient is established, and, by reverse transcriptase-PCR and RNase transcription analysis, the wild-type transcript and a transcript in which exon 3 sequences are absent without disruption of the translational reading frame are identified. Sequencing and hybridization analysis show a deletion of >6 kb in intron 2 of the human AR gene, starting 18 bp upstream of exon 3. The deletion includes the putative branch-point sequence (BPS) but not the acceptor splice site on the intron 2/exon 3 boundary. The deletion of the putative intron 2 BPS results in 90% inhibition of wild-type splicing. The mutant transcript encodes an AR protein lacking the second zinc finger of the DNA-binding domain. Western/immunoblotting analysis is used to show that the mutant AR protein is expressed in genital skin fibroblasts of the patient. The residual 10% wild-type transcript can be the result of the use of a cryptic BPS located 63 bp upstream of the intron 2/exon 3 boundary of the mutant AR gene. The mutated AR protein has no transcription-activating potential and does not influence the transactivating properties of the wild-type AR, as tested in cotransfection studies. It is concluded that the partial androgen-insensitivity syndrome of this patient is the consequence of the limited amount of wild-type AR protein expressed in androgen target cells, resulting from the deletion of the intron 2 putative BPS. 42 refs., 6 figs., 1 tab.

  14. Human α(2)β(1)(HI) CD133(+VE) epithelial prostate stem cells express low levels of active androgen receptor.

    PubMed

    Williamson, Stuart C; Hepburn, Anastasia C; Wilson, Laura; Coffey, Kelly; Ryan-Munden, Claudia A; Pal, Deepali; Leung, Hing Y; Robson, Craig N; Heer, Rakesh

    2012-01-01

    Stem cells are thought to be the cell of origin in malignant transformation in many tissues, but their role in human prostate carcinogenesis continues to be debated. One of the conflicts with this model is that cancer stem cells have been described to lack androgen receptor (AR) expression, which is of established importance in prostate cancer initiation and progression. We re-examined the expression patterns of AR within adult prostate epithelial differentiation using an optimised sensitive and specific approach examining transcript, protein and AR regulated gene expression. Highly enriched populations were isolated consisting of stem (α(2)β(1)(HI) CD133(+VE)), transiently amplifying (α(2)β(1)(HI) CD133(-VE)) and terminally differentiated (α(2)β(1)(LOW) CD133(-VE)) cells. AR transcript and protein expression was confirmed in α(2)β(1)(HI) CD133(+VE) and CD133(-VE) progenitor cells. Flow cytometry confirmed that median (±SD) fraction of cells expressing AR were 77% (±6%) in α(2)β(1)(HI) CD133(+VE) stem cells and 68% (±12%) in α(2)β(1)(HI) CD133(-VE) transiently amplifying cells. However, 3-fold lower levels of total AR protein expression (peak and median immunofluorescence) were present in α(2)β(1)(HI) CD133(+VE) stem cells compared with differentiated cells. This finding was confirmed with dual immunostaining of prostate sections for AR and CD133, which again demonstrated low levels of AR within basal CD133(+VE) cells. Activity of the AR was confirmed in prostate progenitor cells by the expression of low levels of the AR regulated genes PSA, KLK2 and TMPRSS2. The confirmation of AR expression in prostate progenitor cells allows integration of the cancer stem cell theory with the established models of prostate cancer initiation based on a functional AR. Further study of specific AR functions in prostate stem and differentiated cells may highlight novel mechanisms of prostate homeostasis and insights into tumourigenesis.

  15. Polymorphism of the long polyglutamine tract in the human androgen receptor influences craving of men in alcohol withdrawal.

    PubMed

    Lenz, Bernd; Jacob, Claudia; Frieling, Helge; Jacobi, Andrea; Hillemacher, Thomas; Muschler, Marc; Watson, Kathryn; Kornhuber, Johannes; Bleich, Stefan

    2009-08-01

    Until recently, genetic mechanisms influencing craving in alcohol withdrawal were poorly understood. Studies show that alcoholism is associated with dysregulation of sexual hormones. The androgen receptor is encoded by the trinucleotide repeat CAG. Long repeat regions have been shown to inhibit interactions between the androgen receptor and different co-activators. The aim of the present study was to determine whether or not this trinucleotide repeat is involved in the pathogenesis of alcohol dependence, withdrawal and craving. We included 112 male inpatients who were admitted for detoxification treatment. To measure the extent of craving we used the Obsessive Compulsive Drinking Scale on the day of hospital admission. Regarding total and obsessive craving we found a significant negative correlation for the androgen receptor repeat length. No significant difference between the group of patients and the control group was found. We found that reduced length of the investigated trinucleotide repeat might aggravate craving symptoms. Moreover, an elevated number of repeats might be protective against severe craving. In summary, the presented data points to an underestimated role of the genetic regulation of androgens in the pathogenesis of alcohol dependence and related disorders.

  16. Cardiovascular physiology of androgens and androgen testosterone therapy in postmenopausal women.

    PubMed

    Ling, Shanhong; Komesaroff, Paul A; Sudhir, Krishnankutty

    2009-03-01

    Women before menopause are at relatively lower risk of cardiovascular disease (CVD) compared with age-matched men and after menopause this gender advantage disappears. Androgen has been known to be an independent factor contributing to the higher male susceptibility to CVD, through adverse effects on lipids, blood pressure, and glucose metabolism. High androgen levels also contribute to CVD development in women with polycystic ovary syndrome as well as androgen abusing athletes and body builders. On the other hand, decline in androgen levels, as a result of ageing in men, is associated with hypertension, diabetes and atherosclerosis. Postmenopausal women, particularly those with oophorectomy are generally in low levels of sex hormones and androgen insufficiency is independently associated with the higher incidence of atherosclerosis in postmenopausal women. Androgen testosterone therapy (ATT) has been commonly used to improve well-being and libido in aging men with low androgen levels. The therapy has been demonstrated also to effectively reduce atherogenesis in these people. The use of ATT in postmenopausal women has increased in recent years and to date, however, the cardiovascular benefits of such therapy in these women remain uncertain. This review focuses on research regarding the impact of endogenous androgens and ATT on the cardiovascular physiology and CVD development in postmenopausal women.

  17. Independent Histories of Human Y Chromosomes from Melanesia and Australia

    PubMed Central

    Kayser, Manfred; Brauer, Silke; Weiss, Gunter; Schiefenhövel, Wulf; Underhill, Peter A.; Stoneking, Mark

    2001-01-01

    To investigate the origins and relationships of Australian and Melanesian populations, 611 males from 18 populations from Australia, Melanesia, and eastern/southeastern Asia were typed for eight single-nucleotide polymorphism (SNP) loci and seven short tandem-repeat loci on the Y chromosome. A unique haplotype, DYS390.1del/RPS4Y711T, was found at a frequency of 53%–69% in Australian populations, whereas the major haplotypes found in Melanesian populations (M4G/M5T/M9G and DYS390.3del/RPS4Y711T) are absent from the Australian populations. The Y-chromosome data thus indicate independent histories for Australians and Melanesians, a finding that is in agreement with evidence from mtDNA but that contradicts some analyses of autosomal loci, which show a close relationship between Australian and Melanesian (specifically, highland Papua New Guinean) populations. Since the Australian and New Guinean landmasses were connected when first colonized by humans ⩾50,000 years ago but separated some 8,000 years ago, a possible way to reconcile all the genetic data is to infer that the Y-chromosome and mtDNA results reflect the past 8,000 years of independent history for Australia and New Guinea, whereas the autosomal loci reflect the long preceding period of common origin and shared history. Two Y-chromosome haplotypes (M119C/M9G and M122C/M9G) that originated in eastern/southeastern Asia are present in coastal and island Melanesia but are rare or absent in both Australia and highland Papua New Guinea. This distribution, along with demographic analyses indicating that population expansions for both haplotypes began ∼4,000–6,000 years ago, suggests that these haplotypes were brought to Melanesia by the Austronesian expansion. Most of the populations in this study were previously typed for mtDNA SNPs; population differentiation is greater for the Y chromosome than for mtDNA and is significantly correlated with geographic distance, a finding in agreement with results of

  18. Effect of inter-cycle interval on oocyte production in humans in the presence of the weak androgen DHEA and follicle stimulating hormone: a case-control study

    PubMed Central

    2014-01-01

    Background In various animal models androgens have been demonstrated to enhance follicle stimulating hormone (FSH) activity on granulosa cells during small growing follicle stages. To assess whether similar synergism may also exist in humans we investigated women on androgen (dehydroepiandrosterone, DHEA) supplementation with varying concomitant FSH exposure. Methods In a case controlled cohort study we determine if time interval between IVF cycles of IVF treatment with FSH had an effect on ovarian response to ovulation induction in women supplemented with DHEA. Among 85 women with known low functional ovarian reserve (LFOR), supplemented with DHEA, and undergoing at least 3 consecutive IVF cycles, 68 demonstrated short (<120 days) intervals between repeated cycles (Group 1) and were, therefore, considered to have consistent FSH exposure. In contrast 17 women (Group 2) demonstrated long (> = 120 days) intervals between repeated cycles and, therefore, were considered to demonstrate inconsistent FSH exposure. Trends in oocyte yields were compared between these groups, utilizing mixed model repeated measures ANOVA, adjusted for initial age and FSH dose. Results Only women in Group I demonstrated a linear increase in oocyte yields across their three cycles of treatments (F = 7.92; df 1, 68.6; p = 0.017). Moreover, the analysis revealed a significant interaction between the two patient groups and cycle number for retrieved oocytes (F = 6.32, df = 2, 85.9, p = 0.003). Conclusions This study offers preliminary confirmatory evidence that repeated short interval exposure to androgens in combination with FSH improves human FOR. A higher level of evidence will require prospectively randomized studies. PMID:25048047

  19. Androgenic and Estrogenic Response of Green Mussel Extracts from Singapore’s Coastal Environment Using a Human Cell-Based Bioassay

    PubMed Central

    Bayen, Stéphane; Gong, Yinhan; Chin, Hong Soon; Lee, Hian Kee; Leong, Yong Eu; Obbard, Jeffrey Philip

    2004-01-01

    In the last decade, evidence of endocrine disruption in biota exposed to environmental pollutants has raised serious concern. Human cell-based bioassays have been developed to evaluate induced androgenic and estrogenic activities of chemical compounds. However, bioassays have been sparsely applied to environmental samples. In this study we present data on sex hormone activities in the green mussel, Perna viridis, in Singapore’s coastal waters. P. viridis is a common bioindicator of marine contamination, and this study is a follow-up to an earlier investigation that reported the presence of sex hormone activities in seawater samples from Singapore’s coastal environment. Specimens were collected from eight locations around the Singapore coastline and analyzed for persistent organic pollutants (POPs) and heavy metals. Tissue extracts were then screened for activities on androgen receptors (ARs) and estrogen receptors (ER-α and ER-β) using a reporter gene bio-assay based on a HeLa human cell line. Mussel extracts alone did not exhibit AR activity, but in the presence of the reference androgenic hormone dihydrotestosterone (DHT), activities were up to 340% higher than those observed for DHT alone. Peak activities were observed in locations adjacent to industrial and shipping activities. Estrogenic activities of the mussel extract both alone and in the presence of reference hormone were positive. Correlations were statistically investigated between sex hormone activities, levels of pollutants in the mussel tissues, and various biological parameters (specimen size, sex ratio, lipid and moisture content). Significant correlations exist between AR activities, in the presence of DHT, and total concentration of POPs (r = 0.725, p < 0.05). PMID:15531429

  20. Ovarian and Adrenal Androgens and Their Link to High Human Chorionic Gonadotropin Levels: A Prospective Controlled Study

    PubMed Central

    Rodríguez-Gutiérrez, René; Villarreal-Pérez, Jesús Zacarías; Morales-Martinez, Felipe Arturo; Rodríguez-Guajardo, René; González-Saldivar, Gloria; Mancillas-Adame, Leonardo G.; Alvarez-Villalobos, Neri Alejandro; Lavalle-Gonzalez, Fernando Javier; González-González, José Gerardo

    2014-01-01

    Background. Although the association between human chorionic gonadotropin (hCG) and hyperandrogenism was identified more than 40 years ago, relevant questions remain unanswered. Design and Methods. We conducted a prospective, longitudinal, and controlled study in 23 women with a diagnosis of a complete hydatidiform mole (HM). Results. All participants completed the study. Before HM evacuation mean hCG was markedly higher in the cases than in the control group (P ≤ 0.001). Free testosterone (T) and dehydroepiandrosterone sulfate (DHEA-S) were found to be higher in the cases (2.78 ± 1.24 pg/mL and 231.50 ± 127.20 μ/dL) when compared to the control group (1.50 ± 0.75 pg/mL and 133.59 ± 60.69 μ/dL) (P = 0.0001 and 0.001), respectively. There was a strong correlation between hCG and free T/total T/DHEA-S concentrations (r = 0.78; P ≤ 0.001, r = 0.74;  P ≤ 0.001, and r = 0.71;  P ≤ 0.001), respectively. In the cases group 48 hours after HM evacuation, hCG levels were found to be significantly lower when compared to initial levels (P = 0.001) and free T and DHEA-S declined significantly (P = 0.0002 and 0.009). Conclusion. Before uterus evacuation, hCG, free T, and DHEA-S levels were significantly higher when compared with controls finding a strong correlation between hCG and free T/DHEA-S levels. Forty-eight hours after HM treatment hCG levels declined and the difference was lost. A novel finding of our study is that in cases, besides free T, DHEA-S was also found to be significantly higher and both the ovaries and adrenal glands appear to be the sites of this androgen overproduction. PMID:25505909

  1. Ovarian and adrenal androgens and their link to high human chorionic gonadotropin levels: a prospective controlled study.

    PubMed

    Rodríguez-Gutiérrez, René; Villarreal-Pérez, Jesús Zacarías; Morales-Martinez, Felipe Arturo; Rodríguez-Guajardo, René; González-Saldivar, Gloria; Mancillas-Adame, Leonardo G; Alvarez-Villalobos, Neri Alejandro; Lavalle-Gonzalez, Fernando Javier; González-González, José Gerardo

    2014-01-01

    Background. Although the association between human chorionic gonadotropin (hCG) and hyperandrogenism was identified more than 40 years ago, relevant questions remain unanswered. Design and Methods. We conducted a prospective, longitudinal, and controlled study in 23 women with a diagnosis of a complete hydatidiform mole (HM). Results. All participants completed the study. Before HM evacuation mean hCG was markedly higher in the cases than in the control group (P ≤ 0.001). Free testosterone (T) and dehydroepiandrosterone sulfate (DHEA-S) were found to be higher in the cases (2.78 ± 1.24 pg/mL and 231.50 ± 127.20 μ/dL) when compared to the control group (1.50 ± 0.75 pg/mL and 133.59 ± 60.69 μ/dL) (P = 0.0001 and 0.001), respectively. There was a strong correlation between hCG and free T/total T/DHEA-S concentrations (r = 0.78; P ≤ 0.001, r = 0.74;  P ≤ 0.001, and r = 0.71;  P ≤ 0.001), respectively. In the cases group 48 hours after HM evacuation, hCG levels were found to be significantly lower when compared to initial levels (P = 0.001) and free T and DHEA-S declined significantly (P = 0.0002 and 0.009). Conclusion. Before uterus evacuation, hCG, free T, and DHEA-S levels were significantly higher when compared with controls finding a strong correlation between hCG and free T/DHEA-S levels. Forty-eight hours after HM treatment hCG levels declined and the difference was lost. A novel finding of our study is that in cases, besides free T, DHEA-S was also found to be significantly higher and both the ovaries and adrenal glands appear to be the sites of this androgen overproduction.

  2. 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

  3. Androgen-responsive gene database: integrated knowledge on androgen-responsive genes.

    PubMed

    Jiang, Mei; Ma, Yunsheng; Chen, Congcong; Fu, Xuping; Yang, Shu; Li, Xia; Yu, Guohua; Mao, Yumin; Xie, Yi; Li, Yao

    2009-11-01

    Androgen signaling plays an important role in many biological processes. Androgen Responsive Gene Database (ARGDB) is devoted to providing integrated knowledge on androgen-controlled genes. Gene records were collected on the basis of PubMed literature collections. More than 6000 abstracts and 950 original publications were manually screened, leading to 1785 human genes, 993 mouse genes, and 583 rat genes finally included in the database. All the collected genes were experimentally proved to be regulated by androgen at the expression level or to contain androgen-responsive regions. For each gene important details of the androgen regulation experiments were collected from references, such as expression change, androgen-responsive sequence, response time, tissue/cell type, experimental method, ligand identity, and androgen amount, which will facilitate further evaluation by researchers. Furthermore, the database was integrated with multiple annotation resources, including National Center for Biotechnology Information, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway, to reveal the biological characteristics and significance of androgen-regulated genes. The ARGDB web site is mainly composed of the Browse, Search, Element Scan, and Submission modules. It is user friendly and freely accessible at http://argdb.fudan.edu.cn. Preliminary analysis of the collected data was performed. Many disease pathways, such as prostate carcinogenesis, were found to be enriched in androgen-regulated genes. The discovered androgen-response motifs were similar to those in previous reports. The analysis results are displayed in the web site. In conclusion, ARGDB provides a unified gateway to storage, retrieval, and update of information on androgen-regulated genes.

  4. Androgen therapy in women.

    PubMed

    Arlt, Wiebke

    2006-01-01

    Androgens in women either derive from direct ovarian production or from peripheral conversion of the adrenal sex steroid precursor, dehydroepiandrosterone, towards active androgens. Therefore, loss of adrenal or ovarian function, caused by Addison's disease or consequent to bilateral oophorectomy, results in severe androgen deficiency, clinically often associated with a loss of libido and energy. Importantly, physiological menopause does not necessarily lead to androgen deficiency, as androgen synthesis in the ovaries may persist despite the decline in estrogen production. However, the definition of female androgen deficiency, as recently provided by the Princeton consensus statement, is not precise enough and may lead to over-diagnosis due to the high prevalence of its diagnostic criteria: androgen levels below or within the lower quartile of the normal range and concurrent sexual dysfunction. Importantly, physiological menopause is not necessarily associated with androgen deficiency and therefore does not routinely require androgen therapy. Current replacement options include transdermal testosterone administration or dehydroepiandrosterone treatment, both of which have been shown to result in significant improvements, in particular in libido and mood, while effects on body composition and muscular function are not well documented. It is important to keep in mind that the number of randomized controlled trials is still limited and that currently none of the available preparations is officially approved for use in women. Currently, androgen replacement should be reserved for women with severe androgen deficiency due to an established cause and matching clinical signs and symptoms. PMID:16381985

  5. Structural and functional association of androgen receptor with telomeres in prostate cancer cells

    PubMed Central

    Zhou, Junying; Richardson, Michelle; Reddy, Vidyavathi; Menon, Mani; Barrack, Evelyn R.; Reddy, G. Prem-Veer; Kim, Sahn-Ho

    2013-01-01

    Telomeres protect the ends of linear chromosomes from being recognized as damaged DNA, and telomere stability is required for genome stability. Here we demonstrate that telomere stability in androgen receptor (AR)-positive LNCaP human prostate cancer cells is dependent on AR and androgen, as AR inactivation by AR antagonist bicalutamide (Casodex), AR-knockdown, or androgen-depletion caused telomere dysfunction, and the effect of androgen-depletion or Casodex was blocked by the addition of androgen. Notably, neither actinomycin D nor cycloheximide blocked the DNA damage response to Casodex, indicating that the role of AR in telomere stability is independent of its role in transcription. We also demonstrate that AR is a component of telomeres, as AR-bound chromatin contains telomeric DNA, and telomeric chromatin contains AR. Importantly, AR inactivation by Casodex caused telomere aberrations, including multiple abnormal telomere signals, remindful of a fragile telomere phenotype that has been described previously to result from defective telomere DNA replication. We suggest that AR plays an important role in telomere stability and replication of telomere DNA in prostate cancer cells, and that AR inactivation-mediated telomere dysfunction may contribute to genomic instability and progression of prostate cancer cells. PMID:23363843

  6. Immunohistochemical detection of the androgen receptor with monoclonal antibody F39.4 in routinely processed, paraffin-embedded human tissues after microwave pre-treatment.

    PubMed

    Janssen, P J; Brinkmann, A O; Boersma, W J; Van der Kwast, T H

    1994-08-01

    We describe the immunohistochemical detection of the human androgen receptor (AR) in routinely processed, paraffin-embedded tissue with the monoclonal antibody (MAb) F39.4. Deparaffinized sections were heated in a microwave oven for antigen retrieval. A panel of human male- and female-derived tissues was investigated. We observed a nuclear staining pattern consistent with previous results on frozen sections. Moreover, we studied the possibility of detecting AR in prolonged formalin-fixed tissue and in paraffin-embedded archival material. After prolonged fixation times or long-term storage of paraffin-embedded tissue, the staining intensity for the AR did not deteriorate. Blocking experiments with the specific synthetic peptides demonstrated the specificity of this technique. We conclude that this method is specific, allows retrospective AR studies, and offers optimally preserved morphology.

  7. Docetaxel induces Bcl-2- and pro-apoptotic caspase-independent death of human prostate cancer DU145 cells

    PubMed Central

    OGURA, TAKEHARU; TANAKA, YOSHIYUKI; TAMAKI, HIROKI; HARADA, MAMORU

    2016-01-01

    Docetaxel is a useful chemotherapeutic agent for the first-line treatment of hormone-refractory prostate cancer. Abnormal expression of Bcl-2 is commonly found in cancer cells, which increases their anti-apoptotic potency and chemo-resistance. We investigated the effects of Bcl-2 expression status on the susceptibility of DU145 cells, an androgen-independent human prostate cancer cell line, to docetaxel and other anticancer agents. A panel of Bcl-2-expressing DU145 cell lines was established. Bcl-2 expression levels were unrelated to the susceptibility of DU145 cells to docetaxel. The sensitivity of DU145 cells to cisplatin fluctuated, and the sensitivity to tumor necrosis factor (TNF)-α was decreased by Bcl-2 overexpression. In a xenograft mouse model, overexpression of Bcl-2 drastically decreased the sensitivity of DU145 cells to cisplatin and TNF-α; however, there was no change in the response to docetaxel. Fluorescent microscopy revealed that Bcl-2-overexpression had no effect on the docetaxel-induced death of DU145 cells, but significantly decreased DU145 cell death induced by cisplatin or TNF-α. Interestingly, docetaxel hardly induced caspase-3/7 activation in control or Bcl-2-overexpressing DU145 cells, but did at a low level in LNCaP cells, another prostate cancer cell line. Moreover, in contrast to LNCaP cells, the reduced viabilities of docetaxel-treated control and Bcl-2-overexpressing DU145 cells were not restored by the addition of either a Bid inhibitor or a panel of pro-apoptotic caspase inhibitors. These findings indicate that the antitumor effects of docetaxel on DU145 cells are independent of both Bcl-2 and pro-apoptotic caspases. PMID:27082738

  8. Analysis of androgen receptor and anti-Müllerian hormone pathways in human granulosa cells under luteinizing hormone treatment

    PubMed Central

    2013-01-01

    Background The objective of this study was to determine the gene expression profiles of the androgen/androgen receptor (AR) and anti-Müllerian hormone (AMH)/ Sry-related high-mobility group box 9 (SOX9) pathways in granulosa-luteal cells from patients undergoing standard in vitro fertilization (IVF) with or without recombinant luteinizing hormone (rLH) therapy. Methods Levels of reproductive hormones in the pre-ovulatory follicular fluid and the expression levels of LHR (luteinizing hormone receptor), AR, SOX9, AMH, AR-associated protein 54(ARA54)and ARA70 were determined in granulosa-luteal cells by real-time reverse-transcription PCR. The effects of androgen and rLH treatments on AR and AMH expression levels were also tested in vitro using HO23 cells. Results We collected 35 an 70 granulosa cell samples from patients cycled with and without rLH supplementation, respectively. The clinical outcomes were similar in patients who received rLH therapy and those who did not, though the pre-ovulatory follicular fluid levels of androstenedione, testosterone, and estradiol were significantly higher and progesterone was lower in the rLH supplementation group. Moreover, granulosa-luteal cell mRNA levels of LHR, AR, AMH, and SOX9 were significantly higher in the rLH supplementation group relative to the group that did not receive rLH supplementation. In addition, we observed significant correlations between LHR and AR mRNA expression and among AR, AMH, and SOX9 mRNA expression in granulosa-luteal cells from patients undergoing standard IVF treatment. Conclusions Increased expression of LHR, AR, AMH, and SOX9 is characteristic of granulosa-luteal cells from IVF/ intracytoplasmic sperm injection (ICSI) patients receiving rLH supplementation. PMID:23433069

  9. Androgens in pregnancy: roles in parturition

    PubMed Central

    Makieva, Sofia; Saunders, Philippa T.K.; Norman, Jane E.

    2014-01-01

    potential roles for androgens in myometrial relaxation via non-genomic, AR-independent pathways critical for the pregnancy reaching term. Understanding of the molecular events leading to myometrial relaxation is an important step towards development of novel targeted tocolytic drugs. CONCLUSIONS The increase in androgen levels throughout gestation is likely to be important for establishment and maintenance of pregnancy and initiation of parturition. Further investigation of the underlying mechanisms of androgen action on cervical remodelling and myometrial contractility is needed. The insights gained may facilitate the development of new therapeutic approaches to manage pregnancy complications such as preterm birth. PMID:24643344

  10. Clinical outcomes of anti-androgen withdrawal and subsequent alternative anti-androgen therapy for advanced prostate cancer following failure of initial maximum androgen blockade

    PubMed Central

    MOMOZONO, HIROYUKI; MIYAKE, HIDEAKI; TEI, HIROMOTO; HARADA, KEN-ICHI; FUJISAWA, MASATO

    2016-01-01

    The present study aimed to investigate the significance of anti-androgen withdrawal and/or subsequent alternative anti-androgen therapy in patients with advanced prostate cancer (PC) who relapsed after initial maximum androgen blockade (MAB). The present study evaluated the clinical outcomes of 272 consecutive advanced PC patients undergoing anti-androgen withdrawal and/or subsequent alternative anti-androgen therapy with flutamide following the failure of initial MAB using bicalutamide. With the exception of 41 patients (15.1%) who did not undergo anti-androgen withdrawal due to the characteristics of PC suggesting aggressive diseases, prostate-specific antigen (PSA) declined from the baseline value in 83 patients (35.9%), including 18 (7.8%) with PSA decline >50%, but not in the remaining 148 (64.1%). No significant difference in the overall survival (OS) or cancer-specific survival (CSS) among the three groups was observed based on the response to anti-androgen withdrawal. Following the introduction of alternative anti-androgen therapy with flutamide, PSA decline was observed in 185 patients (68.0%), including 103 (37.9%) who achieved a PSA reduction of >50%; however, the PSA level continued to elevate in the remaining 87 (32.0%). Furthermore, of the numerous factors examined, only the duration of the initial MAB therapy was shown to be significantly correlated with the PSA decline following alternative anti-androgen therapy. Multivariate analysis of several factors identified revealed that only PSA decline following alternative anti-androgen therapy was an independent predictor of CSS and OS. If initial MAB is effective, the introduction of alternative anti-androgen therapy may be considered; however, anti-androgen withdrawal should be omitted, irrespective of the characteristics of advanced PC. PMID:27123292

  11. Bioactive androgens and glucuronidated androgen metabolites are associated with subcutaneous and ectopic skeletal muscle adiposity among older black men.

    PubMed

    Miljkovic, Iva; Cauley, Jane A; Dressen, Amy S; Gordon, Christopher L; Goodpaster, Bret H; Kuller, Lewis H; Bunker, Clareann H; Patrick, Alan L; Wheeler, Victor W; Orwoll, Eric S; Zmuda, Joseph M

    2011-08-01

    Aging is associated with declining serum levels of androgenic hormones and with increased skeletal muscle fat infiltration, an emerging risk factor for type 2 diabetes mellitus (T2DM). Androgens regulate fat mass and glucose homeostasis, but the effect of androgenic hormones on skeletal muscle fat infiltration is largely unknown. Thus, the aim of the current study was to examine the association of serum androgens and their precursors and metabolites with skeletal muscle fat infiltration and T2DM in a black male population group at high risk of T2DM. Serum androgens, estrogens, and androgen precursors and metabolites were measured using mass spectrometry; and calf skeletal muscle fat distribution (subcutaneous and intermuscular fat; skeletal muscle density) was measured using quantitative computed tomography in 472 Afro-Caribbean men 65 years and older. Bioactive androgens, testosterone, free testosterone, and dihydrotestosterone were associated with less skeletal muscle fat infiltration (r = -0.14 to -0.18, P < .05) and increased skeletal muscle density (r = 0.10 to 0.14, P < .05), independent of total adiposity. In addition, glucuronidated androgen metabolites were associated with less subcutaneous fat (r = -0.11 to -0.15, P < .05). Multivariate logistic regression analysis identified an increased level of 3α-diol-3 glucuronide (odds ratio = 1.38, P < .01) and a decreased level of dihydrotestosterone (odds ratio = 0.66, P < .01) to be significantly associated with T2DM. Our findings suggest that, in elderly black men, independent of total adiposity, bioactive androgens and glucuronidated androgen metabolites may play previously unrecognized role in skeletal muscle fat distribution. Longitudinal studies are needed to further evaluate the relationship between androgens and androgen metabolites with changes in skeletal muscle fat distribution with aging and the incidence of T2DM. PMID:21353258

  12. Human skin cells support thymus-independent T cell development.

    PubMed

    Clark, Rachael A; Yamanaka, Kei-ichi; Bai, Mei; Dowgiert, Rebecca; Kupper, Thomas S

    2005-11-01

    Thymic tissue has previously been considered a requirement for the generation of a functional and diverse population of human T cells. We report that fibroblasts and keratinocytes from human skin arrayed on a synthetic 3-dimensional matrix support the development of functional human T cells from hematopoietic precursor cells in the absence of thymic tissue. Newly generated T cells contained T cell receptor excision circles, possessed a diverse T cell repertoire, and were functionally mature and tolerant to self MHC, indicating successful completion of positive and negative selection. Skin cell cultures expressed the AIRE, Foxn1, and Hoxa3 transcription factors and a panel of autoantigens. Skin and bone marrow biopsies can thus be used to generate de novo functional and diverse T cell populations for potential therapeutic use in immunosuppressed patients. PMID:16224538

  13. Human skin cells support thymus-independent T cell development

    PubMed Central

    Clark, Rachael A.; Yamanaka, Kei-ichi; Bai, Mei; Dowgiert, Rebecca; Kupper, Thomas S.

    2005-01-01

    Thymic tissue has previously been considered a requirement for the generation of a functional and diverse population of human T cells. We report that fibroblasts and keratinocytes from human skin arrayed on a synthetic 3-dimensional matrix support the development of functional human T cells from hematopoietic precursor cells in the absence of thymic tissue. Newly generated T cells contained T cell receptor excision circles, possessed a diverse T cell repertoire, and were functionally mature and tolerant to self MHC, indicating successful completion of positive and negative selection. Skin cell cultures expressed the AIRE, Foxn1, and Hoxa3 transcription factors and a panel of autoantigens. Skin and bone marrow biopsies can thus be used to generate de novo functional and diverse T cell populations for potential therapeutic use in immunosuppressed patients. PMID:16224538

  14. Establishment of long-term monolayer cultures of somatic cells from human fetal testes and expansion of peritubular myoid cells in the presence of androgen.

    PubMed

    Cowan, Gillian; Childs, Andrew J; Anderson, Richard A; Saunders, Philippa T K

    2010-04-01

    The somatic (Sertoli cell (SC), Leydig cell (LC), and peritubular myoid (PTM) cell) cells play key roles in development of the fetal testis. We established monolayer cultures from second trimester human testes and investigated the pattern of expression of cell-lineage characteristic mRNAs. Expression of some SC-associated genes (SRY, SOX9, WT1, GATA4, and SF1) was detectable up to and including passage 3 (P3), while others (anti-Müllerian hormone; desert hedgehog) present prior to dissociation were not expressed in the cultured cells. Transcripts encoding the androgen receptor were expressed but addition of dihydrotestosterone (DHT) had no impact on expression of mRNAs expressed in SC or LC. Total concentrations of mRNAs encoding smooth muscle actin (ACTA2) and desmin increased from P1 to P3; an increasing proportion of the cells in the cultures were immunopositive for ACTA2 consistent with proliferation/differentiation of PTM cells. In conclusion, somatic cell monolayer cultures were established from human fetal testes; these cultures could form the basis for future studies based on isolation of purified populations of somatic cells and manipulation of gene expression that is difficult to achieve with organ culture systems. Our results suggest that fetal SC do not maintain a fully differentiated phenotype in vitro, yet PTM (ACTA2 positive) cells readily adapt to monolayer culture conditions in the presence of DHT. This culture system provides an opportunity to study the impact of regulatory factors on gene expression in PTM cells, a population thought to play a key role in mediating androgen action within the developing testis. PMID:20089665

  15. Seminal vesicles and urinary bladder as sites of aromatization of androgens in men, evidenced by a CYP19A1-driven luciferase reporter mouse and human tissue specimens.

    PubMed

    Strauss, Leena; Rantakari, Pia; Sjögren, Klara; Salminen, Anu; Lauren, Eve; Kallio, Jenny; Damdimopoulou, Pauliina; Boström, Minna; Boström, Peter J; Pakarinen, Pirjo; Zhang, FuPing; Kujala, Paula; Ohlsson, Claes; Mäkelä, Sari; Poutanen, Matti

    2013-04-01

    The human CYP19A1 gene is expressed in various tissues by the use of tissue-specific promoters, whereas the rodent cyp19a1 gene is expressed mainly in the gonads and brain. We generated a transgenic mouse model containing a >100-kb 5' region of human CYP19A1 gene connected to a luciferase reporter gene. The luciferase activity in mouse tissues mimicked the CYP19A1 gene expression pattern in humans. Interestingly, the reporter gene activity was 16 and 160 times higher in the urinary bladder and seminal vesicles, respectively, as compared with the activity in the testis. Accordingly, CYP19A1 gene and P450arom protein expression was detected in those human tissues. Moreover, the data revealed that the expression of CYP19A1 gene is driven by promoters PII, I.4, and I.3 in the seminal vesicles, and by promoters PII and I.4 in the urinary bladder. Furthermore, the reporter gene expression in the seminal vesicles was androgen dependent: Castration decreased the expression ∼20 times, and testosterone treatment restored it to the level of an intact mouse. This reporter mouse model facilitates studies of tissue-specific regulation of the human CYP19A1 gene, and our data provide evidence for seminal vesicles as important sites for estrogen production in males.

  16. In situ androgen and estrogen biosynthesis in endometrial cancer: focus on androgen actions and intratumoral production.

    PubMed

    Ito, Kiyoshi; Miki, Yasuhiro; Suzuki, Takashi; McNamara, Keely May; Sasano, Hironobu

    2016-07-01

    In situ estrogen biosynthesis is considered to play pivotal roles in the development and progression of human endometrial carcinoma. However, the biological roles of androgen have remained virtually unknown. Various epidemiological studies have revealed that elevated serum androgen levels are generally associated with an increased risk of developing endometrial carcinoma; however, studies directly examining androgens in carcinoma tissues are relatively rare and reviews summarizing this information are scarce. Therefore, we summarized recent studies on androgens in endometrial carcinoma, especially focusing androgen actions and in situ androgen biosynthesis. Among the enzymes required for local biosynthesis of androgen, 17β-hydroxysteroid dehydrogenase type 5 (conversion from androstenedione to testosterone) and 5α-reductase (reduction of testosterone to dihydrotestosterone (DHT)) are the principal enzymes involved in the formation of biologically most potent androgen, DHT. Both enzymes and androgen receptor were expressed in endometrial carcinoma tissues, and in situ production of DHT has been reported to exist in endometrial carcinoma tissues. However, testosterone is not only a precursor of DHT production, but also a precursor of estradiol synthesis, as a substrate of the aromatase enzyme. Therefore, aromatase could be another key enzyme serving as a negative regulator for in situ production of DHT by reducing amounts of the precursor. In an in vitro study, DHT was reported to exert antiproliferative effects on endometrial carcinoma cells. Intracrine mechanisms of androgens, the downstream signals of AR, which are directly related to anticancer progression, and the clinical significance of DHT-AR pathway in the patients with endometrial carcinoma have, however, not been fully elucidated. PMID:27287451

  17. Inhibitor of p52 NF-κB subunit and androgen receptor (AR) interaction reduces growth of human prostate cancer cells by abrogating nuclear translocation of p52 and phosphorylated AR(ser81).

    PubMed

    Mehraein-Ghomi, Farideh; Church, Dawn R; Schreiber, Cynthia L; Weichmann, Ashley M; Basu, Hirak S; Wilding, George

    2015-09-01

    Accumulating evidence shows that androgen receptor (AR) activation and signaling plays a key role in growth and progression in all stages of prostate cancer, even under low androgen levels or in the absence of androgen in the castration-resistant prostate cancer. Sustained activation of AR under androgen-deprived conditions may be due to its interaction with co-activators, such as p52 NF-κB subunit, and/or an increase in its stability by phosphorylation that delays its degradation. Here we identified a specific inhibitor of AR/p52 interaction, AR/p52-02, via a high throughput screen based on the reconstitution of Gaussia Luciferase. We found that AR/p52-02 markedly inhibited growth of both castration-resistant C4-2 (IC50 ∼6 μM) and parental androgen-dependent LNCaP (IC50 ∼4 μM) human prostate cancer cells under low androgen conditions. Growth inhibition was associated with significantly reduced nuclear p52 levels and DNA binding activity, as well as decreased phosphorylation of AR at serine 81, increased AR ubiquitination, and decreased AR transcriptional activity as indicated by decreased prostate-specific antigen (PSA) mRNA levels in both cell lines. AR/p52-02 also caused a reduction in levels of p21(WAF/CIP1), which is a direct AR targeted gene in that its expression correlates with androgen stimulation and mitogenic proliferation in prostate cancer under physiologic levels of androgen, likely by disrupting the AR signaling axis. The reduced level of cyclinD1 reported previously for this compound may be due to the reduction in nuclear presence and activity of p52, which directly regulates cyclinD1 expression, as well as the reduction in p21(WAF/CIP1), since p21(WAF/CIP1) is reported to stabilize nuclear cyclinD1 in prostate cancer. Overall, the data suggest that specifically inhibiting the interaction of AR with p52 and blocking activity of p52 and pARser81 may be an effective means of reducing castration-resistant prostate cancer cell growth.

  18. Differential Efficacy of Combined Therapy With Radiation and AEE788 in High and Low EGFR-Expressing Androgen-Independent Prostate Tumor Models

    SciTech Connect

    Huamani, Jessica; Willey, Christopher; Thotala, Dinesh; Niermann, Kenneth J.; Reyzer, Michelle; Leavitt, Lauren; Jones, Cameron; Fleishcher, Arthur; Caprioli, Richard; Hallahan, Dennis E.; Kim, Dong Wook Nathan

    2008-05-01

    Purpose: To determine the efficacy of combining radiation (XRT) with a dual epidermal growth factor receptor (EGFR)/vascular endothelial growth factor receptor inhibitor, AEE788, in prostate cancer models with different levels of EGFR expression. Methods and Materials: Immunoblotting was performed for EGFR, phosphorylated-EGFR, and phosphorylated-AKT in prostate cancer cells. Clonogenic assays were performed on DU145, PC-3, and human umbilical vein endothelial cells treated with XRT {+-} AEE788. Tumor xenografts were established for DU145 and PC-3 on hind limbs of athymic nude mice assigned to four treatment groups: (1) control, (2) AEE788, (3) XRT, and (4) AEE788 + XRT. Tumor blood flow and growth measurements were performed using immunohistochemistry and imaging. Results: AEE788 effectively decreased phosphorylated-EGFR and phosphorylated-AKT levels in DU145 and PC-3 cells. Clonogenic assays showed no radiosensitization for DU145 and PC-3 colonies treated with AEE788 + XRT. However, AEE788 caused decreased proliferation in DU145 cells. AEE788 showed a radiosensitization effect in human umbilical vein endothelial cells and increased apoptosis susceptibility. Concurrent AEE788 + XRT compared with either alone led to significant tumor growth delay in DU145 tumors. Conversely, PC-3 tumors derived no added benefit from combined-modality therapy. In DU145 tumors, a significant decrease in tumor blood flow with combination therapy was shown by using power Doppler sonography and tumor blood vessel destruction on immunohistochemistry. Maldi-spectrometry (MS) imaging showed that AEE788 is bioavailable and heterogeneously distributed in DU145 tumors undergoing therapy. Conclusions: AEE788 + XRT showed efficacy in vitro/in vivo with DU145-based cell models, whereas PC-3-based models were adequately treated with XRT alone without added benefit from combination therapy. These findings correlated with differences in EGFR expression and showed effects on both tumor cell

  19. The value of integrating pre-clinical data to predict nausea and vomiting risk in humans as illustrated by AZD3514, a novel androgen receptor modulator.

    PubMed

    Grant, Claire; Ewart, Lorna; Muthas, Daniel; Deavall, Damian; Smith, Simon A; Clack, Glen; Newham, Pete

    2016-04-01

    Nausea and vomiting are components of a complex mechanism that signals food avoidance and protection of the body against the absorption of ingested toxins. This response can also be triggered by pharmaceuticals. Predicting clinical nausea and vomiting liability for pharmaceutical agents based on pre-clinical data can be problematic as no single animal model is a universal predictor. Moreover, efforts to improve models are hampered by the lack of translational animal and human data in the public domain. AZD3514 is a novel, orally-administered compound that inhibits androgen receptor signaling and down-regulates androgen receptor expression. Here we have explored the utility of integrating data from several pre-clinical models to predict nausea and vomiting in the clinic. Single and repeat doses of AZD3514 resulted in emesis, salivation and gastrointestinal disturbances in the dog, and inhibited gastric emptying in rats after a single dose. AZD3514, at clinically relevant exposures, induced dose-responsive "pica" behaviour in rats after single and multiple daily doses, and induced retching and vomiting behaviour in ferrets after a single dose. We compare these data with the clinical manifestation of nausea and vomiting encountered in patients with castration-resistant prostate cancer receiving AZD3514. Our data reveal a striking relationship between the pre-clinical observations described and the experience of nausea and vomiting in the clinic. In conclusion, the emetic nature of AZD3514 was predicted across a range of pre-clinical models, and the approach presented provides a valuable framework for predicition of clinical nausea and vomiting.

  20. The value of integrating pre-clinical data to predict nausea and vomiting risk in humans as illustrated by AZD3514, a novel androgen receptor modulator.

    PubMed

    Grant, Claire; Ewart, Lorna; Muthas, Daniel; Deavall, Damian; Smith, Simon A; Clack, Glen; Newham, Pete

    2016-04-01

    Nausea and vomiting are components of a complex mechanism that signals food avoidance and protection of the body against the absorption of ingested toxins. This response can also be triggered by pharmaceuticals. Predicting clinical nausea and vomiting liability for pharmaceutical agents based on pre-clinical data can be problematic as no single animal model is a universal predictor. Moreover, efforts to improve models are hampered by the lack of translational animal and human data in the public domain. AZD3514 is a novel, orally-administered compound that inhibits androgen receptor signaling and down-regulates androgen receptor expression. Here we have explored the utility of integrating data from several pre-clinical models to predict nausea and vomiting in the clinic. Single and repeat doses of AZD3514 resulted in emesis, salivation and gastrointestinal disturbances in the dog, and inhibited gastric emptying in rats after a single dose. AZD3514, at clinically relevant exposures, induced dose-responsive "pica" behaviour in rats after single and multiple daily doses, and induced retching and vomiting behaviour in ferrets after a single dose. We compare these data with the clinical manifestation of nausea and vomiting encountered in patients with castration-resistant prostate cancer receiving AZD3514. Our data reveal a striking relationship between the pre-clinical observations described and the experience of nausea and vomiting in the clinic. In conclusion, the emetic nature of AZD3514 was predicted across a range of pre-clinical models, and the approach presented provides a valuable framework for predicition of clinical nausea and vomiting. PMID:26876616

  1. Androgens and the breast.

    PubMed

    Dimitrakakis, Constantine; Bondy, Carolyn

    2009-01-01

    Androgens have important physiological effects in women while at the same time they may be implicated in breast cancer pathologies. However, data on the effects of androgens on mammary epithelial proliferation and/or breast cancer incidence are not in full agreement. We performed a literature review evaluating current clinical, genetic and epidemiological data regarding the role of androgens in mammary growth and neoplasia. Epidemiological studies appear to have significant methodological limitations and thus provide inconclusive results. The study of molecular defects involving androgenic pathways in breast cancer is still in its infancy. Clinical and nonhuman primate studies suggest that androgens inhibit mammary epithelial proliferation and breast growth while conventional estrogen treatment suppresses endogenous androgens. Abundant clinical evidence suggests that androgens normally inhibit mammary epithelial proliferation and breast growth. Suppression of androgens using conventional estrogen treatment may thus enhance estrogenic breast stimulation and possibly breast cancer risk. Addition of testosterone to the usual hormone therapy regimen may diminish the estrogen/progestin increase in breast cancer risk but the impact of this combined use on mammary gland homeostasis still needs evaluation.

  2. Androgens and the breast

    PubMed Central

    2009-01-01

    Androgens have important physiological effects in women while at the same time they may be implicated in breast cancer pathologies. However, data on the effects of androgens on mammary epithelial proliferation and/or breast cancer incidence are not in full agreement. We performed a literature review evaluating current clinical, genetic and epidemiological data regarding the role of androgens in mammary growth and neoplasia. Epidemiological studies appear to have significant methodological limitations and thus provide inconclusive results. The study of molecular defects involving androgenic pathways in breast cancer is still in its infancy. Clinical and nonhuman primate studies suggest that androgens inhibit mammary epithelial proliferation and breast growth while conventional estrogen treatment suppresses endogenous androgens. Abundant clinical evidence suggests that androgens normally inhibit mammary epithelial proliferation and breast growth. Suppression of androgens using conventional estrogen treatment may thus enhance estrogenic breast stimulation and possibly breast cancer risk. Addition of testosterone to the usual hormone therapy regimen may diminish the estrogen/progestin increase in breast cancer risk but the impact of this combined use on mammary gland homeostasis still needs evaluation. PMID:19889198

  3. Man is not a big rat: concerns with traditional human risk assessment of phthalates based on their anti-androgenic effects observed in the rat foetus.

    PubMed

    Habert, René; Livera, Gabriel; Rouiller-Fabre, Virginie

    2014-01-01

    Phthalates provide one of the most documented example evidencing how much we must be cautious when using the traditional paradigm based on extrapolation of experimental data from rodent studies for human health risk assessment of endocrine disruptors (EDs). Since foetal testis is known as one of the most sensitive targets of EDs, phthalate risk assessment is routinely based on the capacity of such compounds to decrease testosterone production by the testis or to impair masculinization in the rat during foetal life. In this paper, the well-established inhibiting effects of phthalates of the foetal Leydig cells function in the rat are briefly reviewed. Then, data obtained in humans and other species are carefully analysed. Already in January 2009, using the organotypic culture system named Fetal Testis Assay (FeTA) that we developed, we reported that phthalates might not affect testosterone production in human foetal testes. Several recent experimental studies using xenografts confirm the absence of detectable anti-androgenic effect of phthalates in the human foetal testes. Epidemiological studies led to contradictory results. Altogether, these findings suggest that phthalates effects on foetal Leydig cells are largely species-specific. Consequently, the phthalate threshold doses that disturb foetal steroidogenesis in rat testes and that are presently used to define the acceptable daily intake levels for human health protection must be questioned. This does not mean that phthalates are safe because these compounds have many deleterious effects upon germ cell development that may be common to the different studied species including human. More generally, the identification of common molecular, cellular or/and phenotypic targets in rat and human testes should precede the choice of the toxicological endpoint in rat to accurately assess the safety threshold of any ED in humans.

  4. Hydrogen sulfide represses androgen receptor transactivation by targeting at the second zinc finger module.

    PubMed

    Zhao, Kexin; Li, Shuangshuang; Wu, Lingyun; Lai, Christopher; Yang, Guangdong

    2014-07-25

    Androgen receptor (AR) signaling is indispensable for the development of prostate cancer from the initial androgen-dependent state to a later aggressive androgen-resistant state. This study examined the role of hydrogen sulfide (H(2)S), a novel gasotransmitter, in the regulation of AR signaling as well as its mediation in androgen-independent cell growth in prostate cancer cells. Here we found that H(2)S inhibits cell proliferation of both androgen-dependent (LNCaP) and antiandrogen-resistant prostate cancer cells (LNCaP-B), with more significance on the latter, which was established by long term treatment of parental LNCaP cells with bicalutamide. The expression of cystathionine γ-lyase (CSE), a major H(2)S producing enzyme in prostate tissue, was reduced in both human prostate cancer tissues and LNCaP-B cells. LNCaP-B cells were resistant to bicalutamide-induced cell growth inhibition, and CSE overexpression could rebuild the sensitivity of LNCaP-B cells to bicalutamide. H(2)S significantly repressed the expression of prostate-specific antigen (PSA) and TMPRSS2, two AR-targeted genes. In addition, H(2)S inhibited AR binding with PSA promoter and androgen-responsive element (ARE) luciferase activity. We further found that AR is post-translationally modified by H(2)S through S-sulfhydration. Mutation of cysteine 611 and cysteine 614 in the second zinc finger module of AR-DNA binding domain diminished the effects of H(2)S on AR S-sulfhydration and AR dimerization. These data suggest that reduced CSE/H2S signaling contributes to antiandrogen-resistant status, and sufficient level of H(2)S is able to inhibit AR transactivation and treat castration-resistant prostate cancer.

  5. Mithramycin A induces apoptosis by regulating the mTOR/Mcl-1/tBid pathway in androgen-independent prostate cancer cells

    PubMed Central

    Choi, Eun-Sun; Chung, Taeho; Kim, Jun-Sung; Lee, Hakmo; Kwon, Ki Han; Cho, Nam-Pyo; Cho, Sung-Dae

    2013-01-01

    Mithramycin A (Mith) is an aureolic acid-type polyketide produced by various soil bacteria of the genus Streptomyces. Mith inhibits myeloid cell leukemia-1 (Mcl-1) to induce apoptosis in prostate cancer, but the molecular mechanism underlying this process has not been fully elucidated. The aim of this study was therefore to investigate the detailed molecular mechanism related to Mith-induced apoptosis in prostate cancer cells. Mith decreased the phosphorylation of mammalian target of rapamycin (mTOR) in both cell lines overexpressing phospho-mTOR compared to RWPE-1 human normal prostate epithelial cells. Mith significantly induced truncated Bid (tBid) and siRNA-mediated knock-down of Mcl-1 increased tBid protein levels. Moreover, Mith also inhibited the phosphorylation of mTOR on serine 2448 and Mcl-1, and increased tBid protein in prostate tumors in athymic nude mice bearing DU145 cells as xenografts. Thus, Mith acts as an effective tumor growth inhibitor in prostate cancer cells through the mTOR/Mcl-1/tBid signaling pathway. PMID:24062605

  6. Proteasome inhibitors induce p53-independent apoptosis in human cancer cells.

    PubMed

    Pandit, Bulbul; Gartel, Andrei L

    2011-01-01

    Proteasome inhibitors are used against human cancer, but their mechanisms of action are not entirely understood. For example, the role of the tumor suppressor p53 is controversial. We reevaluated the role of p53 in proteasome inhibitor-induced apoptosis by using isogenic human cancer cell lines with different p53 status. We found that well-known proteasome inhibitors such as MG132 and bortezomib, as well as the recently discovered proteasome inhibitor thiostrepton, induced p53-independent apoptosis in human cancer cell lines that correlated with p53-independent induction of proapoptotic Noxa but not Puma protein. In addition, these drugs inhibited growth of several cancer cell lines independently of p53 status. Notably, thiostrepton induced more potent apoptosis in HepG2 cells with p53 knockdown than in parental cells with wild-type p53. Our data confirm that proteasome inhibitors generally induce p53-independent apoptosis in human cancer cells.

  7. Postnatal penile growth concurrent with mini-puberty predicts later sex-typed play behavior: Evidence for neurobehavioral effects of the postnatal androgen surge in typically developing boys.

    PubMed

    Pasterski, Vickie; Acerini, Carlo L; Dunger, David B; Ong, Ken K; Hughes, Ieuan A; Thankamony, Ajay; Hines, Melissa

    2015-03-01

    The masculinizing effects of prenatal androgens on human neurobehavioral development are well established. Also, the early postnatal surge of androgens in male infants, or mini-puberty, has been well documented and is known to influence physiological development, including penile growth. However, neurobehavioral effects of androgen exposure during mini-puberty are largely unknown. The main aim of the current study was to evaluate possible neurobehavioral consequences of mini-puberty by relating penile growth in the early postnatal period to subsequent behavior. Using multiple linear regression, we demonstrated that penile growth between birth and three months postnatal, concurrent with mini-puberty, significantly predicted increased masculine/decreased feminine behavior assessed using the Pre-school Activities Inventory (PSAI) in 81 healthy boys at 3 to 4years of age. When we controlled for other potential influences on masculine/feminine behavior and/or penile growth, including variance in androgen exposure prenatally and body growth postnally, the predictive value of penile growth in the early postnatal period persisted. More specifically, prenatal androgen exposure, reflected in the measurement of anogenital distance (AGD), and early postnatal androgen exposure, reflected in penile growth from birth to 3months, were significant predictors of increased masculine/decreased feminine behavior, with each accounting for unique variance. Our findings suggest that independent associations of PSAI with AGD at birth and with penile growth during mini-puberty reflect prenatal and early postnatal androgen exposures respectively. Thus, we provide a novel and readily available approach for assessing effects of early androgen exposures, as well as novel evidence that early postnatal aes human neurobehavioral development.

  8. Postnatal penile growth concurrent with mini-puberty predicts later sex-typed play behavior: Evidence for neurobehavioral effects of the postnatal androgen surge in typically developing boys.

    PubMed

    Pasterski, Vickie; Acerini, Carlo L; Dunger, David B; Ong, Ken K; Hughes, Ieuan A; Thankamony, Ajay; Hines, Melissa

    2015-03-01

    The masculinizing effects of prenatal androgens on human neurobehavioral development are well established. Also, the early postnatal surge of androgens in male infants, or mini-puberty, has been well documented and is known to influence physiological development, including penile growth. However, neurobehavioral effects of androgen exposure during mini-puberty are largely unknown. The main aim of the current study was to evaluate possible neurobehavioral consequences of mini-puberty by relating penile growth in the early postnatal period to subsequent behavior. Using multiple linear regression, we demonstrated that penile growth between birth and three months postnatal, concurrent with mini-puberty, significantly predicted increased masculine/decreased feminine behavior assessed using the Pre-school Activities Inventory (PSAI) in 81 healthy boys at 3 to 4years of age. When we controlled for other potential influences on masculine/feminine behavior and/or penile growth, including variance in androgen exposure prenatally and body growth postnally, the predictive value of penile growth in the early postnatal period persisted. More specifically, prenatal androgen exposure, reflected in the measurement of anogenital distance (AGD), and early postnatal androgen exposure, reflected in penile growth from birth to 3months, were significant predictors of increased masculine/decreased feminine behavior, with each accounting for unique variance. Our findings suggest that independent associations of PSAI with AGD at birth and with penile growth during mini-puberty reflect prenatal and early postnatal androgen exposures respectively. Thus, we provide a novel and readily available approach for assessing effects of early androgen exposures, as well as novel evidence that early postnatal aes human neurobehavioral development. PMID:25597916

  9. Expression, purification and primary crystallographic study of human androgen receptor in complex with DNA and coactivator motifs

    SciTech Connect

    Zhou, X. Edward; Suino-Powell, Kelly; Ludidi, Phumzile L.; McDonnell, Donald P.; Xu, H. Eric

    2012-10-24

    The androgen receptor (AR) is a DNA-binding and hormone-activated transcription factor that plays critical roles in the development and progression of prostate cancer. The transcriptional function of AR is modulated by intermolecular interactions with DNA elements and coactivator proteins, as well as intramolecular interactions between AR domains; thus, the structural information from the full-length AR or a multi-domain fragment is essential for understanding the molecular basis of AR functions. Here we report the expression and purification of full-length AR protein and of a fragment containing its DNA-binding and ligand-binding domains connected by the hinge region in the presence of its natural ligand, dihydrotestosterone. Crystals of ligand-bound full-length AR and of the AR fragment in complex with DNA elements and coactivator motifs have been obtained and diffracted to low resolutions. These results help establish a foundation for pursuing further crystallographic studies of an AR/DNA complex.

  10. Piper cubeba targets multiple aspects of the androgen-signalling pathway. A potential phytotherapy against prostate cancer growth?

    PubMed

    Yam, Jianying; Kreuter, Matthias; Drewe, Juergen

    2008-01-01

    Despite the high prevalence of prostate cancer (PC) in the Western world, there is a dearth of effective medication. Since the androgen-signalling pathway is very much involved in PC growth and development, we investigated the potential of Piper cubeba L. extract, P9605, in targeting multiple events simultaneously within this pathway. This may be more effective compared to an antiandrogen monotherapy. Our results indicated that P9605 inhibited proliferation in androgen-dependent LNCaP human prostate cancer cells by reducing DNA synthesis and inducing apoptosis. This antigrowth effect was less pronounced in androgen-independent PC-3 prostate cancer cell lines. P9605 potently inhibited 5 alpha-reductase II activity, which is responsible for converting testosterone to its active form, dihydrotestosterone (DHT), in the prostate. It also acted as an antagonist at recombinant wild-type androgen receptors (AR). P9605 suppressed cell growth and prostate-specific antigen (PSA) secretion stimulated by physiological concentrations of DHT in LNCaP cells. Interestingly, it down-regulated AR levels. In conclusion, our findings suggest that P9605 may potentially retard the growth of androgen-dependent PC via several mechanisms.

  11. Androgens and prostate disease

    PubMed Central

    Cooper, Lori A; Page, Stephanie T

    2014-01-01

    A growing body of literature has established the anabolic benefits of testosterone (T) therapy in hypogonadal men. However, there remains a paucity of data regarding the risks of exogenous androgen use in older men and the potential for adverse effects on the prostate gland. Whether T therapy in older, hypogonadal men might worsen lower urinary tract symptoms or exacerbate, unmask, or even incite prostate cancer development has tempered enthusiasm for T therapy, while known prostatic disease has served as a relative contraindication to T therapy. Androgens are necessary for the development and maintenance of the prostate gland. However, epidemiologic studies do not consistently find a positive relationship between endogenous serum androgen concentrations and the risk of prostate disease. Recent data demonstrate that 5α-reductase inhibitors decrease the risk of low-grade prostate cancer, suggesting that modifying androgen metabolism may have beneficial effects on prostate health, yet similar reductions in high-grade disease have not been observed, thereby questioning the true clinical benefits of these agents for chemoprevention. Knowing how to best investigate the relationship between androgens and the development of prostate disease given the lack of large, randomized trials is difficult. Accumulating data challenges the assumption that alterations in serum androgens have parallel effects within the prostate hormonal environment or change androgen-regulated processes within the gland. Long-term intervention studies are needed to truly ascertain the effects of androgen manipulation on prostate tissue and disease risk. However, available data do not support the notion that restoring serum androgens to normal physiologic ranges drives prostate disease. PMID:24407178

  12. Pyridine analogues of curcumin exhibit high activity for inhibiting CWR-22Rv1 human prostate cancer cell growth and androgen receptor activation

    PubMed Central

    ZHOU, DAI-YING; ZHAO, SU-QING; DU, ZHI-YUN; ZHENG, XI; ZHANG, KUN

    2016-01-01

    The concentrations required for curcumin to exert its anticancer activity (IC50, 20 µM) are difficult to achieve in the blood plasma of patients, due to the low bioavailability of the compound. Therefore, much effort has been devoted to the development of curcumin analogues that exhibit stronger anticancer activity and a lower IC50 than curcumin. The present study investigated twelve pyridine analogues of curcumin, labeled as groups AN, BN, EN and FN, to determine their effects in CWR-22Rv1 human prostate cancer cells. The inhibitory effects of these compounds on testosterone (TT)-induced androgen receptor (AR) activity was determined by performing an AR-linked luciferase assay and by TT-induced expression of prostate-specific antigen. The results of the current study suggested that the FN group of analogues had the strongest inhibitory effect of growth on CWR-22Rv1 cultured cells, and were the most potent inhibitor of AR activity compared with curcumin, and the AN, BN and EN analogues. Thus, the results of the present study indicate the inhibition of the AR pathways as a potential mechanism for the anticancer effect of curcumin analogues in human prostate cancer cells. Furthermore, curcumin analogues with pyridine as a distal ring and tetrahydrothiopyran-4-one as a linker may be good candidates for the development of novel drugs for the treatment of prostate cancer, by targeting the AR signaling pathway. PMID:27313760

  13. Human Performance Technology (HPT): An Examination of Definitions through Dependent and Independent Variables.

    ERIC Educational Resources Information Center

    Irlbeck, Sonja A.

    2002-01-01

    Provides a chronological perspective of human performance technology (HPT) definitions and an evaluation of them in terms of independent and dependent variables. Discusses human competence and performance technology and compares the definitions with the goals that have been articulated for HPT. (Author/LRW)

  14. Sex bias in CNS autoimmune disease mediated by androgen control of autoimmune regulator.

    PubMed

    Zhu, Meng-Lei; Bakhru, Pearl; Conley, Bridget; Nelson, Jennifer S; Free, Meghan; Martin, Aaron; Starmer, Joshua; Wilson, Elizabeth M; Su, Maureen A

    2016-01-01

    Male gender is protective against multiple sclerosis and other T-cell-mediated autoimmune diseases. This protection may be due, in part, to higher androgen levels in males. Androgen binds to the androgen receptor (AR) to regulate gene expression, but how androgen protects against autoimmunity is not well understood. Autoimmune regulator (Aire) prevents autoimmunity by promoting self-antigen expression in medullary thymic epithelial cells, such that developing T cells that recognize these self-antigens within the thymus undergo clonal deletion. Here we show that androgen upregulates Aire-mediated thymic tolerance to protect against autoimmunity. Androgen recruits AR to Aire promoter regions, with consequent enhancement of Aire transcription. In mice and humans, thymic Aire expression is higher in males compared with females. Androgen administration and male gender protect against autoimmunity in a multiple sclerosis mouse model in an Aire-dependent manner. Thus, androgen control of an intrathymic Aire-mediated tolerance mechanism contributes to gender differences in autoimmunity. PMID:27072778

  15. Clostridium scindens: a human gut microbe with a high potential to convert glucocorticoids into androgens[S

    PubMed Central

    Ridlon, Jason M.; Ikegawa, Shigeo; Alves, João M. P.; Zhou, Biao; Kobayashi, Akiko; Iida, Takashi; Mitamura, Kuniko; Tanabe, Genzoh; Serrano, Myrna; De Guzman, Ainee; Cooper, Patsy; Buck, Gregory A.; Hylemon, Phillip B.

    2013-01-01

    Clostridium scindens American Type Culture Collection 35704 is capable of converting primary bile acids to toxic secondary bile acids, as well as converting glucocorticoids to androgens by side-chain cleavage. The molecular structure of the side-chain cleavage product of cortisol produced by C. scindens was determined to be 11β-hydroxyandrost-4-ene-3,17-dione (11β-OHA) by high-resolution mass spectrometry, 1H and 13C NMR spectroscopy, and X-ray crystallography. Using RNA-Seq technology, we identified a cortisol-inducible (∼1,000-fold) operon (desABCD) encoding at least one enzyme involved in anaerobic side-chain cleavage. The desC gene was cloned, overexpressed, purified, and found to encode a 20α-hydroxysteroid dehydrogenase (HSDH). This operon also encodes a putative “transketolase” (desAB) hypothesized to have steroid-17,20-desmolase/oxidase activity, and a possible corticosteroid transporter (desD). RNA-Seq data suggests that the two-carbon side chain of glucocorticords may feed into the pentose-phosphate pathway and are used as a carbon source. The 20α-HSDH is hypothesized to function as a metabolic “rheostat” controlling rates of side-chain cleavage. Phylogenetic analysis suggests this operon is rare in nature and the desC gene evolved from a gene encoding threonine dehydrogenase. The physiological effect of 11β-OHAD on the host or other gut microbes is currently unknown. PMID:23772041

  16. Ovarian overproduction of androgens

    MedlinePlus

    ... the body's testosterone. Tumors of the ovaries and polycystic ovary syndrome (PCOS) can both cause too much androgen production. ... come back after they have been removed. In polycystic ovary syndrome, these things can reduce symptoms caused by high ...

  17. Simultaneous ionization and analysis of 84 anabolic androgenic steroids in human urine using liquid chromatography-silver ion coordination ionspray/triple-quadrupole mass spectrometry.

    PubMed

    Kim, So-Hee; Cha, Eun-Ju; Lee, Kang Mi; Kim, Ho Jun; Kwon, Oh-Seung; Lee, Jaeick

    2014-01-01

    Metal ion coordination ionspray (M(+) CIS) ionization is a powerful technique to enhance ionization efficiency and sensitivity. In this study, we developed and validated an analytical method for simultaneous ionization and analysis of 84 anabolic androgenic steroids (65 exogenous and 19 endogenous) using liquid chromatography-silver ion coordination ionspray/triple-quadrupole mass spectrometry (LC-Ag(+) CIS/MS/MS). The concentrations of silver ions and organic solvents have been optimized to increase the amount of silver ion coordinated complexes. A combination of 25 μM of silver ions and methanol showed the best sensitivity. The validation results showed the intra- (0.8-9.2%) and inter-day (2.5-14.9%) precisions, limits of detection (0.0005-5.0 ng/mL), and matrix effect (71.8-100.3%) for the screening analysis. No significant ion suppression was observed. In addition, this method was successfully applied to analysis of positive samples from suspected abusers and useful for the detection of the trace levels of anabolic steroids in human urine samples.

  18. ANTXR-1 and -2 independent modulation of a cytotoxicity mediated by anthrax toxin in human cells.

    PubMed

    Fujikura, Daisuke; Toyomane, Kochi; Kamiya, Kozue; Mutoh, Memi; Mifune, Etsuko; Ohnuma, Miyuki; Higashi, Hideaki

    2016-09-01

    Several animal models have shown that anthrax toxin (ATX) elicits a cytotoxic effect on host cells through anthrax toxin receptor (ANTXR) function. In this study, compared with mouse cells, cells obtained from humans exhibited low sensitivity to ATX-mediated cytotoxicity, and the sensitivity was not correlated with expression levels of ANTXRs. ATX treatment also induced a cytotoxic effect in other cultured human cells, human embryonic kidney (HEK) 293 cells, that express ANTXRs at undetectable levels. Furthermore, ectopic expression of ANTXRs in HEK293 cells did not affect the sensitivity to ATX treatment. These findings suggest that there is an ANTXR-independent cytotoxic mechanism in human cells. PMID:27170489

  19. Illicit Use of Androgens and Other Hormones: Recent Advances

    PubMed Central

    Kanayama, Gen; Pope, Harrison G.

    2012-01-01

    Purpose of review To summarize recent advances in studies of illicit use of androgens and other hormones. Recent findings Androgens and other appearance- and performance-enhancing substances are widely abused worldwide. Three notable clusters of findings have emerged in this field in recent years. First, studies almost unanimously find that androgen users engage in polypharmacy, often ingesting other hormones (e.g., human growth hormone, thyroid hormones, and insulin), ergo/thermogenic drugs (e.g., caffeine, ephedrine, clenbuterol), and classical drugs of abuse (e.g., cannabis, opiates, and cocaine). Second, reports of long-term psychiatric and medical adverse effects of androgens continue to accumulate. In cardiovascular research particularly, controlled studies have begun to supersede anecdotal evidence, strengthening the case that androgens (possibly acting synergistically with other abused drugs) may cause significant morbidity and even mortality. Third, it is increasingly recognized that androgen use may lead to a dependence syndrome with both psychological and physiological origins. Androgen dependence likely affects some millions of individuals worldwide, and arguably represents the least studied major class of illicit drug dependence. Summary Given mounting evidence of the adverse effects of androgens and associated polypharmacy, this topic will likely represent an expanding area of research and an issue of growing public-health concern. PMID:22450858

  20. The Rec protein of HERV-K(HML-2) upregulates androgen receptor activity by binding to the human small glutamine-rich tetratricopeptide repeat protein (hSGT).

    PubMed

    Hanke, Kirsten; Chudak, Claudia; Kurth, Reinhard; Bannert, Norbert

    2013-02-01

    The expression of endogenous retroviruses of the HERV-K(HML-2) family is strongly upregulated in germ cell tumors and several other cancers. Although the accessory Rec protein of HERV-K(HML-2) has been shown to induce carcinoma in situ in transgenic mice, to increase the activity of c-myc and to interact with the androgen receptor (AR), whether or not Rec expression is indeed implicated causally in the initiation or progression of any human malignancies remains unclear. We used the yeast two-hybrid system involving the Rec protein of a recently integrated HERV-K(HML-2) element in an effort to identify potential Rec-related oncogenic mechanisms. This revealed the human small glutamine-rich tetratricopeptide repeat (TPR)-containing protein (hSGT) to be a cellular binding partner. The interaction of Rec with this known negative regulator of the AR was confirmed by coimmunoprecipitation, pull-down assays and colocalization studies. The interaction involves the TPR motif of hSGT and takes place in the cytoplasm and in the nucleoli. Using an AR-responsive promoter and gene we could demonstrate that Rec interference with hSGT resulted in an up to five-fold increase in the activity of AR. Furthermore, in AR positive cells, Rec was shown to act as transactivator by enhancing AR-mediated activation of the HERV-K(HML-2) LTR promoter. This is in line with previous observations of elevated HERV-K(HML-2) expression in steroid-regulated tissues. On the basis of our findings we propose a "vicious cycle" model of Rec-driven hyperactivation of the AR leading to increased cell proliferation, inhibition of apoptosis and eventually to tumor induction or promotion.

  1. Development of a novel cell based androgen screening model.

    PubMed

    Campana, Carmela; Rege, Juilee; Turcu, Adina F; Pezzi, Vincenzo; Gomez-Sanchez, Celso E; Robins, Diane M; Rainey, William E

    2016-02-01

    The androgen receptor (AR) mediates the majority of androgen effects on target cells. The DNA cis-regulatory elements that respond to AR share sequence similarity with cis-regulatory elements for glucocorticoid, mineralocorticoid and progesterone receptors (GR, MR and PR, respectively). As a result, many of the current AR screening models are complicated by inaccurate activation of reporters by one of these receptor pathways. Identification of more selective androgen testing systems would be beneficial for clinical, pharmacological and toxicologic screening of AR activators. The present study describes the development of a selective androgen-responsive reporter cell line that expresses AR but does not express GR, MR and PR. CV1 cells were stably transduced to express human AR and an androgen-responsive gaussia luciferase gene. Clonal populations of AR expressing cells were isolated. Quantitative RT-PCR (qPCR) and western analysis confirmed stable integration of AR in the most responsive clonal line which was named 'CV1-ARluc'. Stimulation of CV1AR-luc with androgenic ligands (testosterone and 5α-dihydrotestosterone) for 18h caused an increase in luciferase activity in a dose-dependent manner. Other steroid hormones including aldosterone, cortisol, and progesterone did not stimulate luciferase response. The CV1-ARluc also increased luciferase activity when treated with human serum extracts. In conclusion, the CV1-ARluc cells provide a novel model system for screening of new AR agonists and antagonists and can determine the androgenic activity of human serum samples. PMID:26581480

  2. Differential effects of androgenic and anti-androgenic progestins on fusiform and frontal gray matter volume and face recognition performance.

    PubMed

    Pletzer, Belinda; Kronbichler, Martin; Kerschbaum, Hubert

    2015-01-30

    Effects of oral hormonal contraceptives (OC) on human brain structure and behavior have only recently become a focus of research. Two explorative reports observed larger regional gray matter (GM) volumes in OC users within the prefrontal cortex, ACC and fusiform gyri, as well as parahippocampal gyri, hippocampus and cerebellum. These studies did however not control for the androgenicity of the progestin compound of OC, did not take into consideration how long OC users had been on their OC, and did not control for age differences between the OC group and the naturally cycling group. We compared 20 naturally cycling women during their early follicular cycle phase to 18 users of OC containing androgenic progestins and 22 users of OC containing anti-androgenic progestins. When controlling for age, we found that in users of anti-androgenic progestins relative GM volumes within the bilateral fusiform gyri, fusiform face area (FFA), parahippocampal place area (PPA) and cerebellum, were significantly larger than in naturally cycling women, while in users of androgenic progestins, relative as well as absolute volumes within the bilateral middle and superior frontal gyri were significantly smaller compared to naturally cycling women. These morphological changes were related to performance in a face recognition task. Face recognition performance was significantly better in users of anti-androgenic progestins compared to the other groups and significantly related to absolute as well as relative GM volumes in the FFA and PPA. Total GM volume, as well as absolute GM volumes within the bilateral fusiform gyri, FFA, hippocampus, parahippocampus, PPA, middle frontal gyri and ACC were significantly larger, the longer the duration of OC use, particularly in users of androgenic progestins. Morphological differences between active and inactive pill phase were observed in users of androgenic progestins. These findings suggest differential effects of androgenic and anti-androgenic

  3. Myocytic androgen receptor controls the strength but not the mass of limb muscles.

    PubMed

    Chambon, Céline; Duteil, Delphine; Vignaud, Alban; Ferry, Arnaud; Messaddeq, Nadia; Malivindi, Rocco; Kato, Shigeaki; Chambon, Pierre; Metzger, Daniel

    2010-08-10

    The anabolic effects of androgens on skeletal muscles are thought to be mediated predominantly through the androgen receptor (AR), a member of the ligand-dependent nuclear receptor superfamily. However, despite numerous studies performed in men and in rodents, these effects remain poorly understood. To characterize androgen signaling in skeletal muscles, we generated mice in which the AR is selectively ablated in myofibers. We show that myocytic AR controls androgen-induced insulin-like growth factor IEa (IGF-IEa) expression in the highly androgen-sensitive perineal muscles and that it mediates androgen-stimulated postnatal hypertrophy of these muscles. In contrast, androgen-dependent postnatal hypertrophy of limb muscle fibers is independent of myocytic AR. Thus, androgens control perineal and limb muscle mass in male mice through myocytic AR-dependent and -independent pathways, respectively. Importantly, we also show that AR deficiency in limb myocytes impairs myofibrillar organization of sarcomeres and decreases muscle strength, thus demonstrating that myocytic AR controls key pathways required for maximum force production. These distinct androgen signaling pathways in perineal and limb muscles may allow the design of screens to identify selective androgen modulators of muscle strength.

  4. [Effects of triptolide on the expression of androgen receptor in human prostate LNCaP cells and its mechanism of action].

    PubMed

    Liu, Bi-de; Feng, Qian-qian; Gu, Xiao; Lu, Dan; Li, Wei

    2015-10-01

    To study the regulation of androgen receptor (AR) expression in human prostate cancer LNCaP cells by triptolide (TP) and the possible mechanism, by using qRT-PCR and Western blot, the AR mRNA and protein levels in TP treated LNCaP cells were detected, and the AR protein level in TP and NF-κB inhibitor treated LNCaP cells was also detected; a series of pGL3-AR promoter reporter gene vectors were built using restriction-free cloning method, and the vectors were employed to investigate the effects of TP on the transcriptional activity of AR promoter in LNCaP cells; the upstream proteins which may play regulatory roles were detected using western blot assay. After treated LNCaP cells with TP for 48 h, AR mRNA and protein expressions decreased with increasing TP concentration. The expression of AR target gene PART1 and prostate specific antigen (PSA) was also downregulated by TP treatment; a series of pGL3-AR promoter reporter vectors were constructed and validated by sequencing and luciferase activity; the results of dual luciferase reporter assay showed that TP downregulated AR at the transcriptional level; PI3K/AKT/NF-κB pathway which is associated with AR promoter activity was drowregulated by TP. In conclusion, our results demonstrated that the transcriptional activity of AR in LNCAP cells was downregulated by TP, and PI3K/AKT/NF-κB pathway may be involved in the regulation mechanism. PMID:26837169

  5. PKCα activation down-regulates ATM and radio-sensitizes androgen-sensitive human prostate cancer cells in vitro and in vivo

    PubMed Central

    Truman, Jean-Philip; Rotenberg, Susan A.; Kang, Ji-Hye; Lerman, Gabriel; Fuks, Zvi; Kolesnick, Richard; Marquez, Victor E.; Haimovitz-Friedman, Adriana

    2009-01-01

    We previously demonstrated that treatment of human androgen-responsive prostate cancer cell lines LNCaP and CWR22-Rv1 with 12-O-tetradecanoylphorbol 13-acetate (TPA), a known protein kinase C (PKC) activator, decreases ATM protein levels, thus de-repressing the enzyme ceramide synthase (CS) and promoting apoptosis as well as radio-sensitizing these cells.1 Here we show that PKCα mediates the TPA effect on ATM expression, since ATM suppression and apoptosis induced by either TPA or diacylglycerol-lactone (DAG-lactone), both inducing PKCα activation,2 are abrogated in LNCaP cells following transfection of a kinase-dead PKCα mutant (KD-PKCα). Similarly, KD-PKCα blocks the apoptotic response elicited by combination of TPA and radiation, whereas expression of constitutively active PKCα is sufficient to sensitize cells to radiation alone, without a need to pre-treat the cells with TPA. These findings identify CS activation as a downstream event of PKCα activity in LNCaP cells. Similar results were obtained in CWR22-Rv1 cells with DAG-lactone treatment. Using the LNCaP orthotopic prostate model it is shown that treatment with TPA or DAG-lactone induces significant reduction in tumor ATM levels coupled with tumor growth delay. Furthermore, while fractionated radiation alone produces significant tumor growth delay, pretreatment with TPA or DAG-lactone significantly potentiates tumor cure. These findings support a model in which activation of PKCα downregulates ATM, thus relieving CS repression by ATM and enhancing apoptosis via ceramide generation. This model may provide a basis for the design of new therapies in prostate cancer. PMID:19029835

  6. Simultaneous quantification of cholesterol sulfate, androgen sulfates, and progestagen sulfates in human serum by LC-MS/MS[S

    PubMed Central

    Sánchez-Guijo, Alberto; Oji, Vinzenz; Hartmann, Michaela F.; Traupe, Heiko; Wudy, Stefan A.

    2015-01-01

    Steroids are primarily present in human fluids in their sulfated forms. Profiling of these compounds is important from both diagnostic and physiological points of view. Here, we present a novel method for the quantification of 11 intact steroid sulfates in human serum by LC-MS/MS. The compounds analyzed in our method, some of which are quantified for the first time in blood, include cholesterol sulfate, pregnenolone sulfate, 17-hydroxy-pregnenolone sulfate, 16-α-hydroxy-dehydroepiandrosterone sulfate, dehydroepiandrosterone sulfate, androstenediol sulfate, androsterone sulfate, epiandrosterone sulfate, testosterone sulfate, epitestosterone sulfate, and dihydrotestosterone sulfate. The assay was conceived to quantify sulfated steroids in a broad range of concentrations, requiring only 300 μl of serum. The method has been validated and its performance was studied at three quality controls, selected for each compound according to its physiological concentration. The assay showed good linearity (R2 > 0.99) and recovery for all the compounds, with limits of quantification ranging between 1 and 80 ng/ml. Averaged intra-day and between-day precisions (coefficient of variation) and accuracies (relative errors) were below 10%. The method has been successfully applied to study the sulfated steroidome in diseases such as steroid sulfatase deficiency, proving its diagnostic value. This is, to our best knowledge, the most comprehensive method available for the quantification of sulfated steroids in human blood. PMID:26239050

  7. Androgen Resistance in Squirrel Monkeys (Saimiri spp.)

    PubMed Central

    Gross, Katherine L; Westberry, Jenne M; Hubler, Tina R; Sadosky, Patti W; Singh, Ravinder J; Taylor, Robert L; Scammell, Jonathan G

    2008-01-01

    The goal of this study was to understand the basis for high androgen levels in squirrel monkeys (Saimiri spp.). Mass spectrometry was used to analyze serum testosterone, androstenedione, and dihydrotestosterone of male squirrel monkeys during the nonbreeding (n = 7) and breeding (n = 10) seasons. All hormone levels were elevated compared with those of humans, even during the nonbreeding season; the highest levels occurred during the breeding season. The ratio of testosterone to dihydrotestosterone in squirrel monkeys is high during the breeding season compared to man. Squirrel monkeys may have high testosterone to compensate for inefficient metabolism to dihydrotestosterone. We also investigated whether squirrel monkeys have high androgens to compensate for low-activity androgen receptors (AR). The response to dihydrotestosterone in squirrel monkey cells transfected with AR and AR-responsive reporter plasmids was 4-fold, compared with 28-fold in human cells. This result was not due to overexpression of cellular FKBP51, which causes glucocorticoid and progestin resistance in squirrel monkeys, because overexpression of FKBP51 had no effect on dihydrotestosterone-stimulated reporter activity in a human fibroblast cell line. To test whether the inherently low levels of FKBP52 in squirrel monkeys contribute to androgen insensitivity, squirrel monkey cells were transfected with an AR expression plasmid, an AR-responsive reporter plasmid, and a plasmid expressing FKBP52. Expression of FKBP52 decreased the EC50 or increased the maximal response to dihydrotestosterone. Therefore, the high androgen levels in squirrel monkeys likely compensate for their relatively low 5α-reductase activity during the breeding season and AR insensitivity resulting from low cellular levels of FKBP52. PMID:18724781

  8. Fast and sensitive liquid chromatography-mass spectrometry assay for seven androgenic and progestagenic steroids in human serum.

    PubMed

    Keski-Rahkonen, Pekka; Huhtinen, Kaisa; Poutanen, Matti; Auriola, Seppo

    2011-11-01

    A fast and sensitive LC-MS/MS method for the quantitative analysis of seven steroid hormones in 150 μl of human serum was developed and validated. The following compounds were included: 17α-hydroxypregnenolone, 17α-hydroxyprogesterone, androstenedione, dehydroepiandrosterone, testosterone, pregnenolone, and progesterone. Individual stable isotope-labeled analogues were used as internal standards. Sample preparation was performed by liquid-liquid extraction, followed by oxime derivatization to improve the ionization efficiency of the analytes. In contrast to the common derivatization-based methods, the reaction was incorporated into the sample preparation process and the only additional step due to the derivatization was a short heating of the autosampler vials before the sample injection. Chromatographic separation was achieved on a reversed-phase column using a methanol-water gradient. For the analyte detection, a triple quadrupole instrument with electrospray ionization was used. Total run time was 7.0 min and the lower limits of quantification were in the range of 0.03-0.34 nM (0.01-0.10 ng/ml), depending on the analyte. The method was validated using human serum samples from both sexes and applied for the serum steroid profiling of endometriosis patients.

  9. Tissue-specific expression and androgen regulation of different genes encoding rat prostatic 22-kilodalton glycoproteins homologous to human and rat cystatin.

    PubMed

    Winderickx, J; Hemschoote, K; De Clercq, N; Van Dijck, P; Peeters, B; Rombauts, W; Verhoeven, G; Heyns, W

    1990-04-01

    22-Kilodalton (kDa) protein cDNA clones were isolated from a rat prostatic library. Nucleotide sequence analysis revealed three different cDNA sequences encoding two somewhat different open reading frames of 176 amino acids. The N-terminal 24 amino acids of these sequences show the typical characteristics of signal peptides of secretory proteins. The C-terminal end of the derived protein sequences displays sequence similarity to a number of cysteine proteinase inhibitors, called cystatins, suggesting a common physiological function. Upon Northern blotting with a labeled cDNA fragment, three different 22-kDa protein mRNAs, i.e. 950 nucleotides (nt), 920 nt and 860 nt, could be detected in the rat ventral prostate and the lacrymal gland. In both tissues these messengers were regulated by androgens showing the most rapid androgen response for the 950 nt mRNA form. Administration of cycloheximide nearly completely abolished the observed androgen effect suggesting that a short-living protein is required for the full induction of the 22-kDa protein genes. Hybridization experiments with specific oligonucleotides which distinguish between the mRNAs encoding both 22-kDa protein variants indicate that one protein form is less androgen dependent in the ventral prostate and not expressed in the lacrymal gland.

  10. Vocal cues to male androgen levels in giant pandas.

    PubMed

    Charlton, Benjamin D; Keating, Jennifer L; Kersey, David; Rengui, Li; Huang, Yan; Swaisgood, Ronald R

    2011-02-23

    Little is known about the potential of non-human mammal vocalizations to signal information on the hormonal status of the caller. In the current study, we used endocrine data and acoustic analyses to determine whether male giant panda bleats provide reliable information about the caller's current androgen levels. Our results revealed significant relationships between acoustic features of male giant panda bleats and the caller's faecal androgen metabolite concentrations. To our knowledge, this constitutes the first demonstration that the acoustic structure of a non-human mammal call has the potential to yield information about the caller's current androgen levels. We go on to discuss the anatomical basis for our findings and the potential functional relevance of signalling information on male androgen levels in giant panda sexual communication. PMID:20810426

  11. SATB2 expression increased anchorage-independent growth and cell migration in human bronchial epithelial cells.

    PubMed

    Wu, Feng; Jordan, Ashley; Kluz, Thomas; Shen, Steven; Sun, Hong; Cartularo, Laura A; Costa, Max

    2016-02-15

    The special AT-rich sequence-binding protein 2 (SATB2) is a protein that binds to the nuclear matrix attachment region of the cell and regulates gene expression by altering chromatin structure. In our previous study, we reported that SATB2 gene expression was induced in human bronchial epithelial BEAS-2B cells transformed by arsenic, chromium, nickel and vanadium. In this study, we show that ectopic expression of SATB2 in the normal human bronchial epithelial cell-line BEAS-2B increased anchorage-independent growth and cell migration, meanwhile, shRNA-mediated knockdown of SATB2 significantly decreased anchorage-independent growth in Ni transformed BEAS-2B cells. RNA sequencing analyses of SATB2 regulated genes revealed the enrichment of those involved in cytoskeleton, cell adhesion and cell-movement pathways. Our evidence supports the hypothesis that SATB2 plays an important role in BEAS-2B cell transformation. PMID:26780400

  12. Blind separation of human- and horse-footstep signatures using independent component analysis

    NASA Astrophysics Data System (ADS)

    Mehmood, Asif; Damarla, Thyagaraju

    2012-06-01

    Seismic footstep detection based systems for homeland security applications are important to perimeter protection and other security systems. This paper reports seismic footstep signal separation for a walking horse and a walking human. The well-known Independent Component Analysis (ICA) approach is employed to accomplish this task. ICA techniques have become widely used in audio analysis and source separation. The concept of lCA may actually be seen as an extension of the principal component analysis (PCA), which can only impose independence up to the second order and, consequently, defines directions that are orthogonal. They can also be used in conjunction with a classification method to achieve a high percentage of correct classification and reduce false alarms. In this paper, an ICA based algorithm is developed and implemented on seismic data of human and horse footsteps. The performance of this method is very promising and is demonstrated by the experimental results.

  13. Range and velocity independent classification of humans and animals using a profiling sensor

    NASA Astrophysics Data System (ADS)

    Chari, Srikant; Smith, Forrest; Halford, Carl; Jacobs, Eddie; Brooks, Jason

    2010-04-01

    This paper presents object profile classification results using range and speed independent features from an infrared profiling sensor. The passive infrared profiling sensor was simulated using a LWIR camera. Field data collected near the US-Mexico border to yield profiles of humans and animals is reported. Range and speed independent features based on height and width of the objects were extracted from profiles. The profile features were then used to train and test three classification algorithms to classify objects as humans or animals. The performance of Naïve Bayesian (NB), K-Nearest Neighbors (K-NN), and Support Vector Machines (SVM) are compared based on their classification accuracy. Results indicate that for our data set all three algorithms achieve classification rates of over 98%. The field data is also used to validate our prior data collections from more controlled environments.

  14. 15- and 16-hydroxylations of androgens and estrogens in the human fetal liver: a critical step in estetrol biosynthesis.

    PubMed

    Cantineau, R; Kremers, P; De Graeve, J; Gielen, J E; Lambotte, R

    1985-02-01

    To elucidate the main metabolic pathways which lead to the foeto-placental biosynthesis of estetrol (I), we investigated the 15 alpha- and 16 alpha-hydroxylations of potential precursors of this estrogen in the human fetal liver. We determined the 15 alpha- and 16 alpha-hydroxylation capacity of the fetal liver for each precursor by GC-MS. The results suggest that estetrol is derived only from estradiol sulfate (II) and DHEA sulfate (III). 15 alpha-Hydroxy-androstenedione (IV) can no longer be regarded as a good precursor of estetrol. The phenolic pathway appears to be a more likely route than the neutral pathway, even when derived from DHEA sulfate. PMID:3157024

  15. Molecular insight into the differential anti-androgenic activity of resveratrol and its natural analogs: In Silico approach to understand biological actions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The androgen receptor (AR) is a therapeutic target for the treatment of prostate cancer. Androgen receptor reactivation during the androgen-independent stage of prostate cancer is mediated by numerous mechanisms including expression of AR mutants and splice variants that become non-responsive to con...

  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. Screening for exogenous androgen anabolic steroids in human hair by liquid chromatography/orbitrap-high resolution mass spectrometry.

    PubMed

    Strano-Rossi, Sabina; Castrignanò, Erika; Anzillotti, Luca; Odoardi, Sara; De-Giorgio, Fabio; Bermejo, Ana; Pascali, Vincenzo L

    2013-09-01

    A method for the screening of various anabolic steroids and their esters in human hair, based on liquid-chromatography-high resolution mass spectrometry using an Exactive benchtop Orbitrap mass spectrometer, has been set up and validated. This method involved methanolic incubation of 30 mg of hair and analysis of the relevant extract in HPLC using a C18 column. The mass detector, with nominal resolving power of 100,000, operated in full scan mode in APCI under positive ionization mode. Analytes were identified by exact mass, correspondence of isotopic cluster and retention times. The limits of detection obtained varied from 10 to 50 pg mg(-1), and limits of quantitation were 0.5 ng mg(-1) for all compounds. The method was linear for all analytes in the ranges from the LOQ to 6 ng mg(-1), giving correlation coefficients >0.99 for all analytes. Also accuracy (intended as %E) and repeatability (%CV) were always lower than 15%. Specificity was assessed by analysing ten blank samples and fifteen samples from polidrug abusers. This method was applied to a real-life case, resulting in the identification of testosterone undecanoate in the hair of a suspect. The analyte identity was confirmed by the analysis of its in-source fragmentation and comparison to a certified standard. Thanks to the scan acquisition, this method also enables retrospective re-analysis of the acquired datafile in case a further analyte needs to be screened.

  18. Anti-androgens act jointly in suppressing spiggin concentrations in androgen-primed female three-spined sticklebacks - prediction of combined effects by concentration addition.

    PubMed

    Pottinger, T G; Katsiadaki, I; Jolly, C; Sanders, M; Mayer, I; Scott, A P; Morris, S; Kortenkamp, A; Scholze, M

    2013-09-15

    Increasing attention is being directed at the role played by anti-androgenic chemicals in endocrine disruption of wildlife within the aquatic environment. The co-occurrence of multiple contaminants with anti-androgenic activity highlights a need for the predictive assessment of combined effects, but information about anti-androgen mixture effects on wildlife is lacking. This study evaluated the suitability of the androgenised female stickleback screen (AFSS), in which inhibition of androgen-induced spiggin production provides a quantitative assessment of anti-androgenic activity, for predicting the effect of a four component mixture of anti-androgens. The anti-androgenic activity of four known anti-androgens (vinclozolin, fenitrothion, flutamide, linuron) was evaluated from individual concentration-response data and used to design a mixture containing each chemical at equipotent concentrations. Across a 100-fold concentration range, a concentration addition approach was used to predict the response of fish to the mixture. Two studies were conducted independently at each of two laboratories. By using a novel method to adjust for differences between nominal and measured concentrations, good agreement was obtained between the actual outcome of the mixture exposure and the predicted outcome. This demonstrated for the first time that androgen receptor antagonists act in concert in an additive fashion in fish and that existing mixture methodology is effective in predicting the outcome, based on concentration-response data for individual chemicals. The sensitivity range of the AFSS assay lies within the range of anti-androgenicity reported in rivers across many locations internationally. The approach taken in our study lays the foundations for understanding how androgen receptor antagonists work together in fish and is essential in informing risk assessment methods for complex anti-androgenic mixtures in the aquatic environment.

  19. 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

  20. Enantiomer selective glucuronidation of the non-steroidal pure anti-androgen bicalutamide by human liver and kidney: role of the human UDP-glucuronosyltransferase (UGT)1A9 enzyme

    PubMed Central

    Grosse, Laurent; Campeau, Anne-Sophie; Caron, Sarah; Morin, Frédéric-Alexandre; Meunier, Kim; Trottier, Jocelyn; Caron, Patrick; Verreault, Mélanie; Barbier, Olivier

    2013-01-01

    Bicalutamide (Casodex®) is a non-steroidal pure anti-androgen used in the treatment of localized prostate cancer. It is a racemate drug and its activity resides in the (R)-enantiomer, with little in the (S)-enantiomer. A major metabolic pathway for bicalutamide is glucuronidation catalyzed by UDP-glucuronosyltransferase (UGT) enzymes. While (S)bicalutamide is directly glucuronidated, (R)bicalutamide requires hydroxylation prior to glucuronidation. The contribution of human tissues and UGT isoforms in the metabolism of these enantiomers has not been extensively investigated. In this study, both (R) and/or (S)bicalutamide were converted into glucuronide (-G) derivatives following incubation of pure and racemic solutions with microsomal extracts from human liver and kidney. Intestinal microsomes exhibited only low reactivity with these substrates. Km values of liver and kidney samples for (S)bicalutamide glucuronidation were similar, and lower than values obtained with the (R)-enantiomer. Among the 16 human UGTs tested, UGT1A8 and UGT1A9 were able to form both (S) and (R)bicalutamide-G from pure or racemic substrates. UGT2B7 was also able to form (R)bicalutamide-G. Kinetic parameters of the recombinant UGT2B7, UGT1A8 and UGT1A9 enzymes support a predominant role of the UGT1A9 isoform in bicalutamide metabolism. Accordingly, (S)bicalutamide inhibited the ability of human liver and kidney microsomes to glucuronidate the UGT1A9 probe substrate, propofol. In conclusion, the present study provides the first comprehensive analysis of in vitro bicalutamide glucuronidation by human tissues and UGTs, and identifies UGT1A9 as a major contributor for (R) and (S) glucuronidation in the human liver and kidney. PMID:23527766

  1. Human handling and presentation of a novel object evoke independent dimensions of fear in Japanese quail.

    PubMed

    Richard, S; Land, N; Saint-Dizier, H; Leterrier, C; Faure, J M

    2010-09-01

    Fear is a concept comprising several dimensions, but the nature of these dimensions and the relationships between them remain elusive. To investigate these dimensions in birds, we have used two genetic lines of quail divergently selected on tonic immobility duration, a behavioural index of fear. These two lines differ in their behavioural response to some, but not all, fear-inducing situations. In the present study, we investigated the contribution of human intervention in the differentiation between the two lines. To do this, fear responses towards a novel object were compared between lines in three conditions: (1) in the home cage without any human intervention, (2) in the home cage after human handling and (3) after placement in a novel environment by human handling. Fear behaviour differed between lines after human handling, with or without placement in a novel environment, but presentation of a novel object in the home cage without any human intervention induced similar fear responses in the two lines of quail. These results lead us to suggest that in quail, human intervention evokes a dimension of fear that differs from that evoked by sudden presentation of a novel object, in that these two dimensions may be selected independently.

  2. Augmentation of human monocyte opsonin-independent phagocytosis by fragments of human plasma fibronectin.

    PubMed Central

    Czop, J K; Kadish, J L; Austen, K F

    1981-01-01

    Human plasma fibronectin isolated by gelatin-affinity chromatography increases in a dose-dependent fashion the number of human monocytes that ingest particulate activators of the human alternative complement pathway in a fully synthetic medium. The fibronectin effect is selective for these particulate activators, does not extend to particles whose ingestion is dependent upon opsonization with IgG, and is not observed with pretreatment of the monocytes. Affinity chromatography with monoclonal antibody to plasma fibronectin of 440,000 daltons reveals that only 12-53% of the protein in a phagocytically active gelatin-affinity-purified fibronectin preparations is bound to the antibody. The protein eluted after affinity chromatography with monoclonal antibody of active preparations, which represented 10-43% of the protein applied, exhibits a 2- to 10-fold increment of activity per microgram of protein above the starting gelatin-affinity-purified material. Thus, the activity that augments the percent of human monocytes ingesting particulate activators of the alternative pathway is antigenically defined as plasma fibronectin. Preparations containing only intact 440,000-dalton fibronectin are also bound to and eluted from the monoclonal antibody, but they fail to augment phagocytosis. When inactive 440,000-dalton plasma fibronectin is subjected to limited trypsin cleavage, phagocytosis-enhancing activity develops that is bound to and elutes from the affinity column prepared with monoclonal antibody, thereby indicating that the enhancing activity of plasma fibronectin resides in cleavage fragments. PMID:6943567

  3. Sulforaphane increases the efficacy of anti-androgens by rapidly decreasing androgen receptor levels in prostate cancer cells.

    PubMed

    Khurana, Namrata; Talwar, Sudha; Chandra, Partha K; Sharma, Pankaj; Abdel-Mageed, Asim B; Mondal, Debasis; Sikka, Suresh C

    2016-10-01

    Prostate cancer (PCa) cells utilize androgen for their growth. Hence, androgen deprivation therapy (ADT) using anti-androgens, e.g. bicalutamide (BIC) and enzalutamide (ENZ), is a mainstay of treatment. However, the outgrowth of castration resistant PCa (CRPC) cells remains a significant problem. These CRPC cells express androgen receptor (AR) and utilize the intratumoral androgen towards their continued growth and invasion. Sulforaphane (SFN), a naturally occurring isothiocyanate found in cruciferous vegetables, can decrease AR protein levels. In the present study, we tested the combined efficacy of anti-androgens and SFN in suppressing PCa cell growth, motility and clonogenic ability. Both androgen-dependent (LNCaP) and androgen-independent (C4-2B) cells were used to monitor the effects of BIC and ENZ, alone and in combination with SFN. Co-exposure to SFN significantly (p<0.005) enhanced the anti-proliferative effects of anti-androgens and downregulated expression of the AR-responsive gene, prostate specific antigen (PSA) (p<0.05). Exposure to SFN decreased AR protein levels in a time- and dose-dependent manner with almost no AR detected at 24 h with 15 µM SFN (p<0.005). This rapid and potent AR suppression by SFN occurred by both AR protein degradation, as suggested by cycloheximide (CHX) co-exposure studies, and by suppression of AR gene expression, as evident from quantitative RT-PCR experiments. Pre-exposure to SFN also reduced R1881-stimulated nuclear localization of AR, and combined treatment with SFN and anti-androgens abrogated the mitogenic effects of this AR-agonist (p<0.005). Wound-healing assays revealed that co-exposure to SFN and anti-androgens can significantly (p<0.005) reduce PCa cell migration. In addition, long-term exposures (14 days) to much lower concentrations of these agents, SFN (0.2 µM), BIC (1 µM) and/or ENZ (0.4 µM) significantly (p<0.005) decreased the number of colony forming units (CFUs). These findings clearly suggest that

  4. Androgen Receptor and Histone Lysine Demethylases in Ovine Placenta

    PubMed Central

    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

  5. Metabolic Syndrome, Androgens, and Hypertension

    PubMed Central

    Moulana, Mohadetheh; Lima, Roberta; Reckelhoff, Jane F.

    2013-01-01

    Obesity is one of the constellation of factors that make up the definition of the metabolic syndrome. Metabolic syndrome is also associated with insulin resistance, dyslipidemia, hypertriglyceridemia, and type 2 diabetes mellitus. The presence of obesity and metabolic syndrome in men and women is also associated with increased risk of cardiovascular disease and hypertension. In men, obesity and metabolic syndrome are associated with reductions in testosterone levels. In women, obesity and metabolic syndrome is associated with increases in androgen levels. In men reductions in androgen levels is associated with inflammation. Androgen supplements reduce inflammation in men. In women, increases in androgens are associated with increases in inflammatory cytokines, and reducing androgens reduces inflammation. In this review the possibility that androgens may have different effects on metabolic syndrome and its sequelae in males and females will be discussed. PMID:21274756

  6. Independent Verification and Validation of Complex User Interfaces: A Human Factors Approach

    NASA Technical Reports Server (NTRS)

    Whitmore, Mihriban; Berman, Andrea; Chmielewski, Cynthia

    1996-01-01

    The Usability Testing and Analysis Facility (UTAF) at the NASA Johnson Space Center has identified and evaluated a potential automated software interface inspection tool capable of assessing the degree to which space-related critical and high-risk software system user interfaces meet objective human factors standards across each NASA program and project. Testing consisted of two distinct phases. Phase 1 compared analysis times and similarity of results for the automated tool and for human-computer interface (HCI) experts. In Phase 2, HCI experts critiqued the prototype tool's user interface. Based on this evaluation, it appears that a more fully developed version of the tool will be a promising complement to a human factors-oriented independent verification and validation (IV&V) process.

  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. 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

  9. 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

  10. Novel Insights into Molecular Indicators of Response and Resistance to Modern Androgen-Axis Therapies in Prostate Cancer

    PubMed Central

    Antonarakis, Emmanuel S.

    2016-01-01

    While androgen ablation remains a mainstay for advanced prostate cancer therapy, nearly all patients will inevitably develop disease escape with time. Upon the development of castration-resistant prostate cancer, other androgen-axis-targeted treatments may be added in an effort to starve the disease of its androgen signaling. Nevertheless, additional androgen-pathway resistance usually develops to these novel hormonal therapies. In this review, we will discuss the resistance mechanisms to modern androgen-axis modulators and how these alterations can influence a patient's response to novel hormonal therapy. We conceptualize these resistance pathways as three broad categories: (1) reactivation of androgen/AR-signaling, (2) AR bypass pathways, and (3) androgen/AR-independent mechanisms. We highlight examples of each, as well as potential therapeutic approaches to overcome these resistance mechanisms. PMID:26902623

  11. Red Maca (Lepidium meyenii) did not affect cell viability despite increased androgen receptor and prostate-specific antigen gene expression in the human prostate cancer cell line LNCaP.

    PubMed

    Díaz, P; Cardenas, H; Orihuela, P A

    2016-10-01

    We examined whether aqueous extract of Lepidium meyenii (red Maca) could inhibit growth, potentiate apoptotic activity of two anticancer drugs Taxol and 2-methoxyestradiol (2ME) or change mRNA expression for the androgen target genes, androgen receptor (Ar) and prostate-specific antigen (Psa) in the human prostate cancer cell line LNCaP. Red Maca aqueous extract at 0, 10, 20, 40 or 80 μg/ml was added to LNCaP cells, and viability was evaluated by the MTS assay at 24 or 48 hr after treatment. Furthermore, LNCaP cells were treated with 80 μg/ml of red Maca plus Taxol or 2ME 5 μM and viability was assessed 48 hr later. Finally, LNCaP cells were treated with red Maca 0, 20, 40 or 80 μg/ml, and 12 hr later, mRNA level for Ar or Psa was assessed by real-time PCR. Treatment with red Maca did not affect viability of LNCaP cells. Apoptotic activity induced by Taxol and 2ME in LNCaP cells was not altered with red Maca treatment. Relative expression of the mRNA for Ar and Psa increased with red Maca 20 and 40 μg/ml, but not at 80 μg/ml. We conclude that red Maca aqueous extract does not have toxic effects, but stimulates androgen signalling in LNCaP cells. PMID:27681649

  12. Red Maca (Lepidium meyenii) did not affect cell viability despite increased androgen receptor and prostate-specific antigen gene expression in the human prostate cancer cell line LNCaP.

    PubMed

    Díaz, P; Cardenas, H; Orihuela, P A

    2016-10-01

    We examined whether aqueous extract of Lepidium meyenii (red Maca) could inhibit growth, potentiate apoptotic activity of two anticancer drugs Taxol and 2-methoxyestradiol (2ME) or change mRNA expression for the androgen target genes, androgen receptor (Ar) and prostate-specific antigen (Psa) in the human prostate cancer cell line LNCaP. Red Maca aqueous extract at 0, 10, 20, 40 or 80 μg/ml was added to LNCaP cells, and viability was evaluated by the MTS assay at 24 or 48 hr after treatment. Furthermore, LNCaP cells were treated with 80 μg/ml of red Maca plus Taxol or 2ME 5 μM and viability was assessed 48 hr later. Finally, LNCaP cells were treated with red Maca 0, 20, 40 or 80 μg/ml, and 12 hr later, mRNA level for Ar or Psa was assessed by real-time PCR. Treatment with red Maca did not affect viability of LNCaP cells. Apoptotic activity induced by Taxol and 2ME in LNCaP cells was not altered with red Maca treatment. Relative expression of the mRNA for Ar and Psa increased with red Maca 20 and 40 μg/ml, but not at 80 μg/ml. We conclude that red Maca aqueous extract does not have toxic effects, but stimulates androgen signalling in LNCaP cells.

  13. Studies on culture and osteogenic induction of human mesenchymal stem cells under CO2-independent conditions.

    PubMed

    Chen, Jian; Zhang, Cui; Feng, Yiding; Zong, Chen; Chen, Jiarong; Tang, Zihua; Jia, Bingbing; Tong, Xiangming; Zheng, Qiang; Wang, Jinfu

    2013-04-01

    Human mesenchymal stem cells (hMSCs) are one of the important factors that regulate bone anabolism. Osteoporosis resulting from microgravity during spaceflight may possibly be due to a decrease in osteogenesis mediated by hMSCs. This speculation should be verified through culture and osteogenic induction of hMSCs in a microgravity environment during spaceflight. Control of CO2 is a key component in current experimental protocols for growth, survival, and proliferation of in vitro cultured cells. However, carrying CO2 tanks on a spaceflight and devoting space/mass allowances for classical CO2 control protocols make experimentation on culture and osteogenesis difficult during most missions. Therefore, an experimental culture and osteogenic medium was developed through modifying the components of buffer salts in conventional culture medium. This experimental medium was used to culture and induce hMSCs under CO2-independent conditions. The results showed that culture and induction of hMSCs with conventional culture medium and conventional osteogenic medium under CO2-independent conditions resulted in an increase of pH in medium. The proliferation of hMSCs was also inhibited. hMSCs cultured with experimental culture medium under CO2-independent conditions showed a proliferation potential that was the same as those cultured with conventional culture medium under CO2-dependent conditions. The experimental osteogenic medium could promote hMSCs to differentiate into osteoblast-like cells under CO2-independent conditions. Cells induced by this induction system showed high alkaline phosphatase activity. The expression levels of osteogenic genes in cells induced with experimental osteogenic medium under CO2-independent conditions were not significantly different from those cells induced with conventional osteogenic medium under CO2-dependent conditions. These results suggest that the experimental culture and induction system could be used to culture hMSCs and induce the

  14. Studies on culture and osteogenic induction of human mesenchymal stem cells under CO2-independent conditions.

    PubMed

    Chen, Jian; Zhang, Cui; Feng, Yiding; Zong, Chen; Chen, Jiarong; Tang, Zihua; Jia, Bingbing; Tong, Xiangming; Zheng, Qiang; Wang, Jinfu

    2013-04-01

    Human mesenchymal stem cells (hMSCs) are one of the important factors that regulate bone anabolism. Osteoporosis resulting from microgravity during spaceflight may possibly be due to a decrease in osteogenesis mediated by hMSCs. This speculation should be verified through culture and osteogenic induction of hMSCs in a microgravity environment during spaceflight. Control of CO2 is a key component in current experimental protocols for growth, survival, and proliferation of in vitro cultured cells. However, carrying CO2 tanks on a spaceflight and devoting space/mass allowances for classical CO2 control protocols make experimentation on culture and osteogenesis difficult during most missions. Therefore, an experimental culture and osteogenic medium was developed through modifying the components of buffer salts in conventional culture medium. This experimental medium was used to culture and induce hMSCs under CO2-independent conditions. The results showed that culture and induction of hMSCs with conventional culture medium and conventional osteogenic medium under CO2-independent conditions resulted in an increase of pH in medium. The proliferation of hMSCs was also inhibited. hMSCs cultured with experimental culture medium under CO2-independent conditions showed a proliferation potential that was the same as those cultured with conventional culture medium under CO2-dependent conditions. The experimental osteogenic medium could promote hMSCs to differentiate into osteoblast-like cells under CO2-independent conditions. Cells induced by this induction system showed high alkaline phosphatase activity. The expression levels of osteogenic genes in cells induced with experimental osteogenic medium under CO2-independent conditions were not significantly different from those cells induced with conventional osteogenic medium under CO2-dependent conditions. These results suggest that the experimental culture and induction system could be used to culture hMSCs and induce the

  15. A competitive inhibitor that reduces recruitment of androgen receptor to androgen-responsive genes.

    PubMed

    Cherian, Milu T; Wilson, Elizabeth M; Shapiro, David J

    2012-07-01

    The androgen receptor (AR) has a critical role in the growth and progression of androgen-dependent and castration-resistant prostate cancers. To identify novel inhibitors of AR transactivation that block growth of prostate cancer cells, a luciferase-based high-throughput screen of ~160,000 small molecules was performed in cells stably expressing AR and a prostate-specific antigen (PSA)-luciferase reporter. CPIC (1-(3-(2-chlorophenoxy) propyl)-1H-indole-3-carbonitrile) was identified as a small molecule that blocks AR transactivation to a greater extent than other steroid receptors. CPIC inhibited AR-mediated proliferation of androgen-sensitive prostate cancer cell lines, with minimal toxicity in AR-negative cell lines. CPIC treatment also reduced the anchorage-independent growth of LAPC-4 prostate cancer cells. CPIC functioned as a pure antagonist by inhibiting the expression of AR-regulated genes in LAPC-4 cells that express wild-type AR and exhibited weak agonist activity in LNCaP cells that express the mutant AR-T877A. CPIC treatment did not reduce AR levels or alter its nuclear localization. We used chromatin immunoprecipitation to identify the site of action of CPIC. CPIC inhibited recruitment of androgen-bound AR to the PSA promoter and enhancer sites to a greater extent than bicalutamide. CPIC is a new therapeutic inhibitor that targets AR-mediated gene activation with potential to arrest the growth of prostate cancer.

  16. Independent spatial and temporal functions of human sperm centrosomes after dispermic microinjection into bovine oocytes.

    PubMed

    Terada, Yukihiro; Hasegawa, Hisataka; Ugajin, Tomohisa; Nabeshima, Hiroshi; Suzuki, Kichiya; Yaegashi, Nobuo; Okamura, Kunihiro

    2009-01-01

    During mammalian fertilization, a centrosome is introduced by the sperm during the first cell cycle to organize a radial array of microtubules known as the sperm aster. In nature, multiple human sperm centrosomes may exist in the same egg cytoplasm during polyspermy. However, critical information concerning individual sperm centrosomal function with regards to the latter case remains unknown. We subsequently examined the sperm aster formation after injection of multiple human sperm into a bovine egg. When 2 fertile human sperm were simultaneously microinjected into different regions of the same bovine egg cytoplasm, no difference in sperm aster formation rate was observed compared to cases in which a single sperm was injected. Two human sperm were also microinjected into bovine eggs 30-, 60- and 120-minute intervals apart from one another, and no difference in sperm aster formation rates were observed. Among eggs in which 1 sperm aster was organized, there was no observable bias towards the first or second injected sperm. These findings indicated that when multiple human sperm are present in a single egg cytoplasm, each centrosome can function independently from the other. This fact suggests the possibility of transplanting a normal sperm centrosome into an egg with a sperm known to have centrosomal dysfunction.

  17. 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.

  18. Does field independence predict visuo-spatial abilities underpinning human navigation? Behavioural evidence.

    PubMed

    Boccia, Maddalena; Piccardi, Laura; Di Marco, Mariangela; Pizzamiglio, Luigi; Guariglia, Cecilia

    2016-10-01

    Field independence (FI) has been defined as the extent to which the individual perceives part of a field as discrete from the surrounding field, rather than embedded in the field. It has been proposed to represent a relatively stable pattern in individuals' predisposition towards information processing. In the present study, we assessed the effect of FI on skills underpinning human navigation. Fifty Healthy individuals took part in this study. FI has been assessed by using the group embedded figures test (GEFT). Participants were also asked to perform several visuo-spatial orientation tasks, including the perspective taking/spatial orientation test (PTSOT), the mental rotation task (MRT) and the vividness task, as well as the Santa Barbara Sense of Direction Scale, a self-reported questionnaire, which has been found to predict environmental spatial orientation ability. We found that performances on the GEFT significantly predicted performances on the PTSOT and the MRT. This result supports the idea that FI predicts human navigation.

  19. Cap-independent translation by DAP5 controls cell fate decisions in human embryonic stem cells.

    PubMed

    Yoffe, Yael; David, Maya; Kalaora, Rinat; Povodovski, Lital; Friedlander, Gilgi; Feldmesser, Ester; Ainbinder, Elena; Saada, Ann; Bialik, Shani; Kimchi, Adi

    2016-09-01

    Multiple transcriptional and epigenetic changes drive differentiation of embryonic stem cells (ESCs). This study unveils an additional level of gene expression regulation involving noncanonical, cap-independent translation of a select group of mRNAs. This is driven by death-associated protein 5 (DAP5/eIF4G2/NAT1), a translation initiation factor mediating IRES-dependent translation. We found that the DAP5 knockdown from human ESCs (hESCs) resulted in persistence of pluripotent gene expression, delayed induction of differentiation-associated genes in different cell lineages, and defective embryoid body formation. The latter involved improper cellular organization, lack of cavitation, and enhanced mislocalized apoptosis. RNA sequencing of polysome-associated mRNAs identified candidates with reduced translation efficiency in DAP5-depleted hESCs. These were enriched in mitochondrial proteins involved in oxidative respiration, a pathway essential for differentiation, the significance of which was confirmed by the aberrant mitochondrial morphology and decreased oxidative respiratory activity in DAP5 knockdown cells. Further analysis identified the chromatin modifier HMGN3 as a cap-independent DAP5 translation target whose knockdown resulted in defective differentiation. Thus, DAP5-mediated translation of a specific set of proteins is critical for the transition from pluripotency to differentiation, highlighting the importance of cap-independent translation in stem cell fate decisions.

  20. Cap-independent translation by DAP5 controls cell fate decisions in human embryonic stem cells.

    PubMed

    Yoffe, Yael; David, Maya; Kalaora, Rinat; Povodovski, Lital; Friedlander, Gilgi; Feldmesser, Ester; Ainbinder, Elena; Saada, Ann; Bialik, Shani; Kimchi, Adi

    2016-09-01

    Multiple transcriptional and epigenetic changes drive differentiation of embryonic stem cells (ESCs). This study unveils an additional level of gene expression regulation involving noncanonical, cap-independent translation of a select group of mRNAs. This is driven by death-associated protein 5 (DAP5/eIF4G2/NAT1), a translation initiation factor mediating IRES-dependent translation. We found that the DAP5 knockdown from human ESCs (hESCs) resulted in persistence of pluripotent gene expression, delayed induction of differentiation-associated genes in different cell lineages, and defective embryoid body formation. The latter involved improper cellular organization, lack of cavitation, and enhanced mislocalized apoptosis. RNA sequencing of polysome-associated mRNAs identified candidates with reduced translation efficiency in DAP5-depleted hESCs. These were enriched in mitochondrial proteins involved in oxidative respiration, a pathway essential for differentiation, the significance of which was confirmed by the aberrant mitochondrial morphology and decreased oxidative respiratory activity in DAP5 knockdown cells. Further analysis identified the chromatin modifier HMGN3 as a cap-independent DAP5 translation target whose knockdown resulted in defective differentiation. Thus, DAP5-mediated translation of a specific set of proteins is critical for the transition from pluripotency to differentiation, highlighting the importance of cap-independent translation in stem cell fate decisions. PMID:27664238

  1. Benefits of intermittent/continuous androgen deprivation in patients with advanced prostate cancer

    PubMed Central

    MURESANU, HORIA

    2016-01-01

    Background and aims In 1941 Huggins described the effect of castration on prostate cancer. gonadotropin-releasing hormone (GNRH) analogues were introduced in 1985. Complete androgen blockade (association of GNRH analogue with antiandrogen) was introduced by Fernand Labrie to achieve suppression of suprarenal testosterone. Long time androgen deprivation lead to androgen independence of the prostate cancer cell. Our principal aim was to demonstrate longer survival rates on prostate cancer patients with intermittent androgen deprivation. Methods 82 patients in the Urology Department of Vasile Goldis West University Arad were included into two groups, with continuous and intermittent androgen deprivation. Treatment efficiency was assessed by the level of testosterone and PSA. Adverse events (AE) and serious adverse events were reported according to Common Terminology Criteria of Adverse Events (CTCAE) of the National Cancer Institute (NCI). Results Evolution towards castrate resistant prostate cancer: 12.5% from the intermittent androgen deprivation group and 23.8% from the continuous androgen deprivation group Mortality rate: 15% of patients from the intermittent androgen deprivation group; 19% of patients from the continuous androgen deprivation group Conclusions Better quality of life (Qol) in periods without treatment due to testosteron recovery; Less AE’s and metabolic syndrome (MS) related complications; Better survival and longer time of disease control and Cost reduction. PMID:27547063

  2. Anaerobiosis increases resistance of Neisseria gonorrhoeae to O2-independent antimicrobial proteins from human polymorphonuclear granulocytes.

    PubMed Central

    Casey, S G; Shafer, W M; Spitznagel, J K

    1985-01-01

    We investigated the in vitro resistance of Neisseria gonorrhoeae FA19 to the O2-independent antimicrobial systems of human polymorphonuclear leukocytes. Acid extracts of polymorphonuclear leukocyte granules (crude granule extracts) and a purified granule protein (57 kilodaltons) were, at low concentrations, bactericidal for gonococci under aerobic conditions that permitted growth. However, they were less effective under anaerobic conditions that imposed bacteriostasis. We found that adding sodium nitrite to reduced growth media permitted the growth of strain FA19 in an anaerobic environment. Under these conditions with nitrite, anaerobic cultures of strain FA19 were no more resistant to the crude granule extract and the 57-kilodalton protein than aerobic cultures. In contrast, Salmonella typhimurium SL-1004, a facultative anaerobe, was readily killed by both the crude granule extract and the 57-kilodalton antimicrobial protein regardless of the presence or absence of free molecular oxygen. This is the first demonstration that an isolated antimicrobial protein from polymorphonuclear leukocyte granules is active against bacteria under anaerobic conditions. Our results also indicated that the efficacy of human polymorphonuclear leukocyte O2-independent killing of N. gonorrhoeae may, in part, be inhibited by bacteriostatic conditions imposed by hypoxia. Images PMID:3917976

  3. A Conditional Entropy-Based Independent Component Analysis for Applications in Human Detection and Tracking

    NASA Astrophysics Data System (ADS)

    Lin, Chin-Teng; Siana, Linda; Shou, Yu-Wen; Shen, Tzu-Kuei

    2010-12-01

    We present in this paper a modified independent component analysis (mICA) based on the conditional entropy to discriminate unsorted independent components. We make use of the conditional entropy to select an appropriate subset of the ICA features with superior capability in classification and apply support vector machine (SVM) to recognizing patterns of human and nonhuman. Moreover, we use the models of background images based on Gaussian mixture model (GMM) to handle images with complicated backgrounds. Also, the color-based shadow elimination and head models in ellipse shapes are combined to improve the performance of moving objects extraction and recognition in our system. Our proposed tracking mechanism monitors the movement of humans, animals, or vehicles within a surveillance area and keeps tracking the moving pedestrians by using the color information in HSV domain. Our tracking mechanism uses the Kalman filter to predict locations of moving objects for the conditions in lack of color information of detected objects. Finally, our experimental results show that our proposed approach can perform well for real-time applications in both indoor and outdoor environments.

  4. Net charge and oxygen affinity of human hemoglobin are independent of hemoglobin concentration

    PubMed Central

    1978-01-01

    The dependence of net charge and oxygen affinity of human hemoglobin upon hemoglobin concentration was reinvestigated. In contrast to earlier reports from various laboratories, both functional properties of hemoglobin were found to be independent of hemoglobin concentration. Two findings indicate a concentration-independent net charge of carbonmonoxy hemoglobin at pH 6.6: (A) The pH value of a given carbonmonoty hemoglobin solution remains constant at 6.6 when the hemoglobin concentration is raised from 10 to 40 g/dl, indicating that there is no change in protonation of titratable groups of hemoglobin: (b) the net charge of carbonmonoxy hemoglobin as estimated from the Donnan distribution of 22Na+ shows no dependence on hemoglobin concentration in this concentration range. The oxygen affinity of human hemoglobin was determined from measurements of oxygen concentrations in equilibrated samples using a Lex-O2-Con apparatus (Lexington Instruments, Waltham, Mass.). P50 averaged 11.4 mm Hg at 37 degrees C, pH = 7.2, and ionic strength approximately 0.15. Neither P50 nor Hill's n showed any variation with hemoglobin concentrations increasing from 10 to 40 g/dl. PMID:32221

  5. Studies on Culture and Osteogenic Induction of Human Mesenchymal Stem Cells under CO2-Independent Conditions

    PubMed Central

    Chen, Jian; Zhang, Cui; Feng, Yiding; Zong, Chen; Chen, Jiarong; Tang, Zihua; Jia, Bingbing; Tong, Xiangming; Zheng, Qiang

    2013-01-01

    Abstract Human mesenchymal stem cells (hMSCs) are one of the important factors that regulate bone anabolism. Osteoporosis resulting from microgravity during spaceflight may possibly be due to a decrease in osteogenesis mediated by hMSCs. This speculation should be verified through culture and osteogenic induction of hMSCs in a microgravity environment during spaceflight. Control of CO2 is a key component in current experimental protocols for growth, survival, and proliferation of in vitro cultured cells. However, carrying CO2 tanks on a spaceflight and devoting space/mass allowances for classical CO2 control protocols make experimentation on culture and osteogenesis difficult during most missions. Therefore, an experimental culture and osteogenic medium was developed through modifying the components of buffer salts in conventional culture medium. This experimental medium was used to culture and induce hMSCs under CO2-independent conditions. The results showed that culture and induction of hMSCs with conventional culture medium and conventional osteogenic medium under CO2-independent conditions resulted in an increase of pH in medium. The proliferation of hMSCs was also inhibited. hMSCs cultured with experimental culture medium under CO2-independent conditions showed a proliferation potential that was the same as those cultured with conventional culture medium under CO2-dependent conditions. The experimental osteogenic medium could promote hMSCs to differentiate into osteoblast-like cells under CO2-independent conditions. Cells induced by this induction system showed high alkaline phosphatase activity. The expression levels of osteogenic genes in cells induced with experimental osteogenic medium under CO2-independent conditions were not significantly different from those cells induced with conventional osteogenic medium under CO2-dependent conditions. These results suggest that the experimental culture and induction system could be used to culture hMSCs and induce

  6. Androgen receptor gene polymorphism in zebra species.

    PubMed

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

    2015-09-01

    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

  7. Intermittent versus continuous total androgen blockade in the treatment of patients with advanced hormone-naive prostate cancer: results of a prospective randomized multicenter trial.

    PubMed

    de Leval, Jean; Boca, Philippe; Yousef, Enis; Nicolas, Hubert; Jeukenne, Michel; Seidel, Laurence; Bouffioux, Christian; Coppens, Luc; Bonnet, Pierre; Andrianne, Robert; Wlatregny, David

    2002-12-01

    The aim of this study was to compare the efficacy of total intermittent androgen deprivation (IAD) versus total continuous androgen deprivation (CAD) for treating patients with advanced prostate cancer in a phase III randomized trial. A total of 68 evaluable patients with hormone-naive advanced or relapsing prostate cancer were randomized to receive combined androgen blockade according to a continuous (n = 33) or intermittent (n = 35) regimen. Therapeutic monitoring was assessed by use of serum prostate-specific antigen (PSA) measurements. Patients in the CAD and IAD groups were equally stratified for age, biopsy Gleason score, and baseline serum PSA levels. The outcome variable was time to androgen-independence of the tumor, which was defined as increasing serum PSA levels despite androgen blockade. Mean follow-up was 30.8 months. The 35 IAD-treated patients completed 91 cycles, and 19 of them (54.3%) completed > or = 3 cycles. Median cycle length and percentage of time off therapy were 9.0 months and 59.5, respectively. The estimated 3-year progression rate was significantly lower in the IAD group (7.0% +/- 4.8%) than in the CAD group (38.9% +/- 11.2%, P = 0.0052). Our data suggest that IAD treatment may maintain the androgen-dependent state of advanced human prostate cancer, as assessed by PSA measurements, at least as long as CAD treatment. Further studies with longer follow-up times and larger patient cohorts are needed to determine the comparative impacts of CAD and IAD on survival.

  8. Molecular insight into the differential anti-androgenic activity of resveratrol and its natural analogs: in silico approach to understand biological actions.

    PubMed

    Chakraborty, Sandipan; Kumar, Avinash; Butt, Nasir A; Zhang, Liangfen; Williams, Raquema; Rimando, Agnes M; Biswas, Pradip K; Levenson, Anait S

    2016-05-01

    The androgen receptor (AR) is a therapeutic target for the treatment of prostate cancer. Androgen receptor reactivation during the androgen-independent stage of prostate cancer is mediated by numerous mechanisms including expression of AR mutants and splice variants that become non-responsive to conventional anti-androgenic agents. Resveratrol and its natural analogs exhibit varying degrees of anti-androgenic effects on tumor growth suppression in prostate cancer. However, the structural basis for the observed differential activity remains unknown. Here, anti-androgenic activities of resveratrol and its natural analogs, namely, pterostilbene, piceatannol and trimethoxy-resveratrol were studied in LNCaP cells expressing T877A mutant AR and atomistic simulations were employed to establish the structure activity relationship. Interestingly, essential hydrogen bonding contacts and the binding energies of resveratrol analogs with AR ligand binding domain (LBD), emerge as key differentiating factors for varying anti-androgenic action. Among all the analogs, pterostilbene exhibited strongest anti-androgenic activity and its binding energy and hydrogen bonding interactions pattern closely resembled pure anti-androgen, flutamide. Principal component analysis of our simulation studies revealed that androgenic compounds bind more strongly to AR LBD compared to anti-androgenic compounds and provide conformational stabilization of the receptor in essential subspace. The present study provides critical insight into the structure-activity relationship of the anti-androgenic action of resveratrol analogs, which can be translated further to design novel highly potent anti-androgenic stilbenes. PMID:27063447

  9. Functional cyclic AMP response element in the breast cancer resistance protein (BCRP/ABCG2) promoter modulates epidermal growth factor receptor pathway- or androgen withdrawal-mediated BCRP/ABCG2 transcription in human cancer cells.

    PubMed

    Xie, Yi; Nakanishi, Takeo; Natarajan, Karthika; Safren, Lowell; Hamburger, Anne W; Hussain, Arif; Ross, Douglas D

    2015-03-01

    Phosphorylated cyclic-AMP (cAMP) response element binding protein (p-CREB) is a downstream effector of a variety of important signaling pathways. We investigated whether the human BCRP promoter contains a functional cAMP response element (CRE). 8Br-cAMP, a cAMP analogue, increased the activity of a BCRP promoter reporter construct and BCRP mRNA in human carcinoma cells. Epidermal growth factor receptor (EGFR) pathway activation also led to an increase in p-CREB and in BCRP promoter reporter activity via two major downstream EGFR signaling pathways: the phosphotidylinositol-3-kinase (PI3K)/AKT pathway and the mitogen-activated protein kinase (MAPK) pathway. EGF treatment increased the phosphorylation of EGFR, AKT, ERK and CREB, while simultaneously enhancing BCRP mRNA and functional protein expression. EGF-stimulated CREB phosphorylation and BCRP induction were diminished by inhibition of EGFR, PI3K/AKT or RAS/MAPK signaling. CREB silencing using RNA interference reduced basal levels of BCRP mRNA and diminished the induction of BCRP by EGF. Chromatin immunoprecipitation assays confirmed that a putative CRE site on the BCRP promoter bound p-CREB by a point mutation of the CRE site abolished EGF-induced stimulation of BCRP promoter reporter activity. Furthermore, the CREB co-activator, cAMP-regulated transcriptional co-activator (CRTC2), is involved in CREB-mediated BCRP transcription: androgen depletion of LNCaP human prostate cancer cells increased both CREB phosphorylation and CRTC2 nuclear translocation, and enhanced BCRP expression. Silencing CREB or CRTC2 reduced basal BCRP expression and BCRP induction under androgen-depletion conditions. This novel CRE site plays a central role in mediating BCRP gene expression in several human cancer cell lines following activation of multiple cancer-relevant signaling pathways. PMID:25615818

  10. Evidence for increased tissue androgen sensitivity in neurturin knockout mice.

    PubMed

    Simanainen, Ulla; Gao, Yan Ru Ellen; Desai, Reena; Jimenez, Mark; Spaliviero, Jennifer; Keast, Janet R; Handelsman, David J

    2013-01-01

    Neurturin (NTN) is a member of the glial cell line-derived neurotrophic factor (GDNF) family and signals through GDNF family receptor alpha 2 (GFRα2). We hypothesised that epithelial atrophy reported in the reproductive organs of Ntn (Nrtn)- and Gfrα2 (Gfra2)-deficient mice could be due to NTN affecting the hormonal environment. To investigate this, we compared the reproductive organs of Ntn- and Gfrα2-deficient male mice in parallel with an analysis of their circulating reproductive hormone levels. There were no significant structural changes within the organs of the knockout mice; however, serum and intratesticular testosterone and serum LH levels were very low. To reconcile these observations, we tested androgen sensitivity by creating a dihydrotestosterone (DHT) clamp (castration plus DHT implant) to create fixed circulating levels of androgens, allowing the evaluation of androgen-sensitive endpoints. At the same serum DHT levels, serum LH levels were lower and prostate and seminal vesicle weights were higher in the Ntn knockout (NTNKO) mice than in the wild-type mice, suggesting an increased response to androgens in the accessory glands and hypothalamus and pituitary of the NTNKO mice. Testicular and pituitary responsiveness was unaffected in the NTNKO males, as determined by the response to the human chorionic gonadotrophin or GNRH analogue, leuprolide, respectively. In conclusion, our results suggest that NTN inactivation enhances androgen sensitivity in reproductive and neuroendocrine tissues, revealing a novel mechanism to influence reproductive function and the activity of other androgen-dependent tissues.

  11. A clinical data validated mathematical model of prostate cancer growth under intermittent androgen suppression therapy

    NASA Astrophysics Data System (ADS)

    Portz, Travis; Kuang, Yang; Nagy, John D.

    2012-03-01

    Prostate cancer is commonly treated by a form of hormone therapy called androgen suppression. This form of treatment, while successful at reducing the cancer cell population, adversely affects quality of life and typically leads to a recurrence of the cancer in an androgen-independent form. Intermittent androgen suppression aims to alleviate some of these adverse affects by cycling the patient on and off treatment. Clinical studies have suggested that intermittent therapy is capable of maintaining androgen dependence over multiple treatment cycles while increasing quality of life during off-treatment periods. This paper presents a mathematical model of prostate cancer to study the dynamics of androgen suppression therapy and the production of prostate-specific antigen (PSA), a clinical marker for prostate cancer. Preliminary models were based on the assumption of an androgen-independent (AI) cell population with constant net growth rate. These models gave poor accuracy when fitting clinical data during simulation. The final model presented hypothesizes an AI population with increased sensitivity to low levels of androgen. It also hypothesizes that PSA production is heavily dependent on androgen. The high level of accuracy in fitting clinical data with this model appears to confirm these hypotheses, which are also consistent with biological evidence.

  12. Identification of Light-independent Inhibition of Human Immunodeficiency Virus-1 Infection through Bioguided Fractionation of Hypericum perforatum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Light-dependent activities against enveloped viruses in St. John's Wort (Hypericum perforatum) extracts have been extensively studied. In contrast, light-independent antiviral activity from this species has not. Here, we identify the light-independent inhibition of human immunodeficiency virus-1 (...

  13. Two independent apolipoprotein A5 haplotypes influence human plasma triglyceride levels.

    PubMed

    Pennacchio, Len A; Olivier, Michael; Hubacek, Jaroslav A; Krauss, Ronald M; Rubin, Edward M; Cohen, Jonathan C

    2002-11-15

    The recently identified apolipoprotein A5 gene (APOA5) has been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. We previously identified an APOA5 haplotype (designated APOA5*2) that is present in approximately 16% of Caucasians and is associated with increased plasma triglyceride concentrations. In this report we describe another APOA5 haplotype (APOA5*3) containing the rare allele of the single nucleotide polymorphism c.56C>G that changes serine to tryptophan at codon 19 and is independently associated with high plasma triglyceride levels in three different populations. In a sample of 264 Caucasian men and women with plasma triglyceride concentrations above the 90th percentile or below the 10th percentile, the APOA5*3 haplotype was more than three-fold more common in the group with high plasma triglyceride levels. In a second independently ascertained sample of Caucasian men and women (n=419) who were studied while consuming their self-selected diets as well as after high-carbohydrate diets and high-fat diets, the APOA5*3 haplotype was associated with increased plasma triglyceride levels on all three dietary regimens. In a third population comprising 2660 randomly selected individuals, the APOA5*3 haplotype was found in 12% of Caucasians, 14% of African-Americans and 28% of Hispanics and was associated with increased plasma triglyceride levels in both men and women in each ethnic group. These findings establish that the APOA5 locus contributes significantly to inter-individual variation in plasma triglyceride levels in humans. Together, the APOA5*2 and APOA5*3 haplotypes are found in 25-50% of African-Americans, Hispanics and Caucasians and support the contribution of common human variation to quantitative phenotypes in the general population.

  14. Two independent apolipoprotein a5 Haplotypes influence human plasma triglyceride levels

    SciTech Connect

    Pennacchio, Len A.; Olivier, Michael; Hubacek, Jaroslav A.; Krauss, Ronald M.; Rubin, Edward M.; Cohen, Jonathan C.

    2002-09-16

    The recently identified apolipoprotein A5 gene (APOA5) has been shown to play an important role in determining plasma triglyceride concentrations in humans and mice. We previously identified an APOA5 haplotype (designated APOA5*2) that is present in {approx}16 percent of Caucasians and is associated with increased plasma triglyceride concentrations. In this report we describe another APOA5 haplotype (APOA5*3) containing the rare allele of the single nucleotide polymorphism c.56C>G that changes serine to tryptophan at codon 19 and is independently associated with high plasma triglyceride levels in three different populations. In a sample of 264 Caucasian men and women with plasma triglyceride concentrations above the 90th percentile or below the 10th percentile, the APOA5*3 haplotype was more than three-fold more common in the group with high plasma triglyceride levels. In a second independently ascertained sample of Caucasian men and women (n 1/4 419) who were studied while consuming their self-selected diets as well as after high-carbohydrate diets and high-fat diets, the APOA5*3 haplotype was associated with increased plasma triglyceride levels on all three dietary regimens. In a third population comprising 2660 randomly selected individuals, the APOA5*3 haplotype was found in 12 percent of Caucasians, 14 percent of African-Americans and 28 percent of Hispanics and was associated with increased plasma triglyceride levels in both men and women in each ethnic group. These findings establish that the APOA5 locus contributes significantly to inter-individual variation in plasma triglyceride levels in humans. Together, the APOA5*2 and APOA5*3 haplotypes are found in 25 50 percent of African-Americans, Hispanics and Caucasians and support the contribution of common human variation to quantitative phenotypes in the general population.

  15. Aluminium chloride promotes anchorage-independent growth in human mammary epithelial cells.

    PubMed

    Sappino, André-Pascal; Buser, Raphaële; Lesne, Laurence; Gimelli, Stefania; Béna, Frédérique; Belin, Dominique; Mandriota, Stefano J

    2012-03-01

    Aluminium salts used as antiperspirants have been incriminated as contributing to breast cancer incidence in Western societies. To date, very little or no epidemiological or experimental data confirm or infirm this hypothesis. We report here that in MCF-10A human mammary epithelial cells, a well-established normal human mammary epithelial cell model, long-term exposure to aluminium chloride (AlCl(3) ) concentrations of 10-300 µ m, i.e. up to 100 000-fold lower than those found in antiperspirants, and in the range of those recently measured in the human breast, results in loss of contact inhibition and anchorage-independent growth. These effects were preceded by an increase of DNA synthesis, DNA double strand breaks (DSBs), and senescence in proliferating cultures. AlCl(3) also induced DSBs and senescence in proliferating primary human mammary epithelial cells. In contrast, it had no similar effects on human keratinocytes or fibroblasts, and was not detectably mutagenic in bacteria. MCF-10A cells morphologically transformed by long-term exposure to AlCl(3) display strong upregulation of the p53/p21(Waf1) pathway, a key mediator of growth arrest and senescence. These results suggest that aluminium is not generically mutagenic, but similar to an activated oncogene, it induces proliferation stress, DSBs and senescence in normal mammary epithelial cells; and that long-term exposure to AlCl(3) generates and selects for cells able to bypass p53/p21(Waf1) -mediated cellular senescence. Our observations do not formally identify aluminium as a breast carcinogen, but challenge the safety ascribed to its widespread use in underarm cosmetics. PMID:22223356

  16. Aluminium chloride promotes anchorage-independent growth in human mammary epithelial cells.

    PubMed

    Sappino, André-Pascal; Buser, Raphaële; Lesne, Laurence; Gimelli, Stefania; Béna, Frédérique; Belin, Dominique; Mandriota, Stefano J

    2012-03-01

    Aluminium salts used as antiperspirants have been incriminated as contributing to breast cancer incidence in Western societies. To date, very little or no epidemiological or experimental data confirm or infirm this hypothesis. We report here that in MCF-10A human mammary epithelial cells, a well-established normal human mammary epithelial cell model, long-term exposure to aluminium chloride (AlCl(3) ) concentrations of 10-300 µ m, i.e. up to 100 000-fold lower than those found in antiperspirants, and in the range of those recently measured in the human breast, results in loss of contact inhibition and anchorage-independent growth. These effects were preceded by an increase of DNA synthesis, DNA double strand breaks (DSBs), and senescence in proliferating cultures. AlCl(3) also induced DSBs and senescence in proliferating primary human mammary epithelial cells. In contrast, it had no similar effects on human keratinocytes or fibroblasts, and was not detectably mutagenic in bacteria. MCF-10A cells morphologically transformed by long-term exposure to AlCl(3) display strong upregulation of the p53/p21(Waf1) pathway, a key mediator of growth arrest and senescence. These results suggest that aluminium is not generically mutagenic, but similar to an activated oncogene, it induces proliferation stress, DSBs and senescence in normal mammary epithelial cells; and that long-term exposure to AlCl(3) generates and selects for cells able to bypass p53/p21(Waf1) -mediated cellular senescence. Our observations do not formally identify aluminium as a breast carcinogen, but challenge the safety ascribed to its widespread use in underarm cosmetics.

  17. Allele-Independent Turnover of Human Leukocyte Antigen (HLA) Class Ia Molecules

    PubMed Central

    Prevosto, Claudia; Usmani, M. Farooq; McDonald, Sarah; Gumienny, Aleksandra M.; Key, Tim; Goodman, Reyna S.; Gaston, J. S. Hill; Deery, Michael J.; Busch, Robert

    2016-01-01

    Major histocompatibility complex class I (MHCI) glycoproteins present cytosolic peptides to CD8+ T cells and regulate NK cell activity. Their heavy chains (HC) are expressed from up to three MHC gene loci (human leukocyte antigen [HLA]-A, -B, and -C in humans), whose extensive polymorphism maps predominantly to the antigen-binding groove, diversifying the bound peptide repertoire. Codominant expression of MHCI alleles is thus functionally critical, but how it is regulated is not fully understood. Here, we have examined the effect of polymorphism on the turnover rates of MHCI molecules in cell lines with functional MHCI peptide loading pathways and in monocyte-derived dendritic cells (MoDCs). Proteins were labeled biosynthetically with heavy water (2H2O), folded MHCI molecules immunoprecipitated, and tryptic digests analysed by mass spectrometry. MHCI-derived peptides were assigned to specific alleles and isotypes, and turnover rates quantified by 2H incorporation, after correcting for cell growth. MHCI turnover half-lives ranged from undetectable to a few hours, depending on cell type, activation state, donor, and MHCI isotype. However, in all settings, the turnover half-lives of alleles of the same isotype were similar. Thus, MHCI protein turnover rates appear to be allele-independent in normal human cells. We propose that this is an important feature enabling the normal function and codominant expression of MHCI alleles. PMID:27529174

  18. Fishery-Independent Data Reveal Negative Effect of Human Population Density on Caribbean Predatory Fish Communities

    PubMed Central

    Stallings, Christopher D.

    2009-01-01

    Background Understanding the current status of predatory fish communities, and the effects fishing has on them, is vitally important information for management. However, data are often insufficient at region-wide scales to assess the effects of extraction in coral reef ecosystems of developing nations. Methodology/Principal Findings Here, I overcome this difficulty by using a publicly accessible, fisheries-independent database to provide a broad scale, comprehensive analysis of human impacts on predatory reef fish communities across the greater Caribbean region. Specifically, this study analyzed presence and diversity of predatory reef fishes over a gradient of human population density. Across the region, as human population density increases, presence of large-bodied fishes declines, and fish communities become dominated by a few smaller-bodied species. Conclusions/Significance Complete disappearance of several large-bodied fishes indicates ecological and local extinctions have occurred in some densely populated areas. These findings fill a fundamentally important gap in our knowledge of the ecosystem effects of artisanal fisheries in developing nations, and provide support for multiple approaches to data collection where they are commonly unavailable. PMID:19421312

  19. Allele-Independent Turnover of Human Leukocyte Antigen (HLA) Class Ia Molecules.

    PubMed

    Prevosto, Claudia; Usmani, M Farooq; McDonald, Sarah; Gumienny, Aleksandra M; Key, Tim; Goodman, Reyna S; Gaston, J S Hill; Deery, Michael J; Busch, Robert

    2016-01-01

    Major histocompatibility complex class I (MHCI) glycoproteins present cytosolic peptides to CD8+ T cells and regulate NK cell activity. Their heavy chains (HC) are expressed from up to three MHC gene loci (human leukocyte antigen [HLA]-A, -B, and -C in humans), whose extensive polymorphism maps predominantly to the antigen-binding groove, diversifying the bound peptide repertoire. Codominant expression of MHCI alleles is thus functionally critical, but how it is regulated is not fully understood. Here, we have examined the effect of polymorphism on the turnover rates of MHCI molecules in cell lines with functional MHCI peptide loading pathways and in monocyte-derived dendritic cells (MoDCs). Proteins were labeled biosynthetically with heavy water (2H2O), folded MHCI molecules immunoprecipitated, and tryptic digests analysed by mass spectrometry. MHCI-derived peptides were assigned to specific alleles and isotypes, and turnover rates quantified by 2H incorporation, after correcting for cell growth. MHCI turnover half-lives ranged from undetectable to a few hours, depending on cell type, activation state, donor, and MHCI isotype. However, in all settings, the turnover half-lives of alleles of the same isotype were similar. Thus, MHCI protein turnover rates appear to be allele-independent in normal human cells. We propose that this is an important feature enabling the normal function and codominant expression of MHCI alleles. PMID:27529174

  20. HES6 promotes prostate cancer aggressiveness independently of Notch signalling

    PubMed Central

    Carvalho, Filipe L F; Marchionni, Luigi; Gupta, Anuj; Kummangal, Basheer A; Schaeffer, Edward M; Ross, Ashley E; Berman, David M

    2015-01-01

    Notch signalling is implicated in the pathogenesis of a variety of cancers, but its role in prostate cancer is poorly understood. However, selected Notch pathway members are overrepresented in high-grade prostate cancers. We comprehensively profiled Notch pathway components in prostate cells and found prostate cancer-specific up-regulation of NOTCH3 and HES6. Their expression was particularly high in androgen responsive lines. Up- and down-regulating Notch in these cells modulated expression of canonical Notch targets, HES1 and HEY1, which could also be induced by androgen. Surprisingly, androgen treatment also suppressed Notch receptor expression, suggesting that androgens can activate Notch target genes in a receptor-independent manner. Using a Notch-sensitive Recombination signal binding protein for immunoglobulin kappa J region (RBPJ) reporter assay, we found that basal levels of Notch signalling were significantly lower in prostate cancer cells compared to benign cells. Accordingly pharmacological Notch pathway blockade did not inhibit cancer cell growth or viability. In contrast to canonical Notch targets, HES6, a HES family member known to antagonize Notch signalling, was not regulated by Notch signalling, but relied instead on androgen levels, both in cultured cells and in human cancer tissues. When engineered into prostate cancer cells, reduced levels of HES6 resulted in reduced cancer cell invasion and clonogenic growth. By molecular profiling, we identified potential roles for HES6 in regulating hedgehog signalling, apoptosis and cell migration. Our results did not reveal any cell-autonomous roles for canonical Notch signalling in prostate cancer. However, the results do implicate HES6 as a promoter of prostate cancer progression. PMID:25864518

  1. ATM-independent, high-fidelity nonhomologous end joining predominates in human embryonic stem cells.

    PubMed

    Adams, Bret R; Hawkins, Amy J; Povirk, Lawrence F; Valerie, Kristoffer

    2010-09-01

    We recently demonstrated that human embryonic stem cells (hESCs) utilize homologous recombination repair (HRR) as primary means of double-strand break (DSB) repair. We now show that hESCs also use nonhomologous end joining (NHEJ). NHEJ kinetics were several-fold slower in hESCs and neural progenitors (NPs) than in astrocytes derived from hESCs. ATM and DNA-PKcs inhibitors were ineffective or partially effective, respectively, at inhibiting NHEJ in hESCs, whereas progressively more inhibition was seen in NPs and astrocytes. The lack of any major involvement of DNA-PKcs in NHEJ in hESCs was supported by siRNA-mediated DNA-PKcs knockdown. Expression of a truncated XRCC4 decoy or XRCC4 knock-down reduced NHEJ by more than half suggesting that repair is primarily canonical NHEJ. Poly(ADP-ribose) polymerase (PARP) was dispensable for NHEJ suggesting that repair is largely independent of backup NHEJ. Furthermore, as hESCs differentiated a progressive decrease in the accuracy of NHEJ was observed. Altogether, we conclude that NHEJ in hESCs is largely independent of ATM, DNA-PKcs, and PARP but dependent on XRCC4 with repair fidelity several-fold greater than in astrocytes.

  2. AMPK-independent inhibition of human macrophage ER stress response by AICAR

    PubMed Central

    Boß, Marcel; Newbatt, Yvette; Gupta, Sahil; Collins, Ian; Brüne, Bernhard; Namgaladze, Dmitry

    2016-01-01

    Obesity-associated insulin resistance is driven by inflammatory processes in response to metabolic overload. Obesity-associated inflammation can be recapitulated in cell culture by exposing macrophages to saturated fatty acids (SFA), and endoplasmic reticulum (ER) stress responses essentially contribute to pro-inflammatory signalling. AMP-activated protein kinase (AMPK) is a central metabolic regulator with established anti-inflammatory actions. Whether pharmacological AMPK activation suppresses SFA-induced inflammation in a human system is unclear. In a setting of hypoxia-potentiated inflammation induced by SFA palmitate, we found that the AMP-mimetic AMPK activator 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) potently suppressed upregulation of ER stress marker mRNAs and pro-inflammatory cytokines. Furthermore, AICAR inhibited macrophage ER stress responses triggered by ER-stressors thapsigargin or tunicamycin. Surprisingly, AICAR acted independent of AMPK or AICAR conversion to 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranosyl monophosphate (ZMP) while requiring intracellular uptake via the equilibrative nucleoside transporter (ENT) ENT1 or the concentrative nucleoside transporter (CNT) CNT3. AICAR did not affect the initiation of the ER stress response, but inhibited the expression of major ER stress transcriptional effectors. Furthermore, AICAR inhibited autophosphorylation of the ER stress sensor inositol-requiring enzyme 1α (IRE1α), while activating its endoribonuclease activity in vitro. Our results suggest that AMPK-independent inhibition of ER stress responses contributes to anti-inflammatory and anti-diabetic effects of AICAR. PMID:27562249

  3. AMPK-independent inhibition of human macrophage ER stress response by AICAR.

    PubMed

    Boß, Marcel; Newbatt, Yvette; Gupta, Sahil; Collins, Ian; Brüne, Bernhard; Namgaladze, Dmitry

    2016-01-01

    Obesity-associated insulin resistance is driven by inflammatory processes in response to metabolic overload. Obesity-associated inflammation can be recapitulated in cell culture by exposing macrophages to saturated fatty acids (SFA), and endoplasmic reticulum (ER) stress responses essentially contribute to pro-inflammatory signalling. AMP-activated protein kinase (AMPK) is a central metabolic regulator with established anti-inflammatory actions. Whether pharmacological AMPK activation suppresses SFA-induced inflammation in a human system is unclear. In a setting of hypoxia-potentiated inflammation induced by SFA palmitate, we found that the AMP-mimetic AMPK activator 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) potently suppressed upregulation of ER stress marker mRNAs and pro-inflammatory cytokines. Furthermore, AICAR inhibited macrophage ER stress responses triggered by ER-stressors thapsigargin or tunicamycin. Surprisingly, AICAR acted independent of AMPK or AICAR conversion to 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranosyl monophosphate (ZMP) while requiring intracellular uptake via the equilibrative nucleoside transporter (ENT) ENT1 or the concentrative nucleoside transporter (CNT) CNT3. AICAR did not affect the initiation of the ER stress response, but inhibited the expression of major ER stress transcriptional effectors. Furthermore, AICAR inhibited autophosphorylation of the ER stress sensor inositol-requiring enzyme 1α (IRE1α), while activating its endoribonuclease activity in vitro. Our results suggest that AMPK-independent inhibition of ER stress responses contributes to anti-inflammatory and anti-diabetic effects of AICAR. PMID:27562249

  4. Determination of benzimidazole- and bicyclic hydantoin-derived selective androgen receptor antagonists and agonists in human urine using LC-MS/MS.

    PubMed

    Thevis, Mario; Kohler, Maxie; Thomas, Andreas; Maurer, Joachim; Schlörer, Nils; Kamber, Matthias; Schänzer, Wilhelm

    2008-05-01

    Selective androgen receptor modulators (SARMs) represent a novel class of drugs with tissue-specific agonistic and antagonistic properties, which are prohibited in sports from January 2008 according to the World Anti-Doping Agency. Preventive approaches to restrict the use of SARMs include early implementation of target analytes into doping control screening assays. Five model SARMs were synthesized, four of which are analogs to prostate-specific androgen receptor antagonists with a 5,6-dichloro-benzimidazole nucleus. The fifth SARM is a muscle-tissue specific agonist with a bicyclic hydantoin structure (BMS-564929). Dissociation pathways after negative electrospray ionization were studied using an LTQ-Orbitrap mass analyzer, and diagnostic product ions and common fragmentation patterns were employed to establish a screening procedure that target the intact SARMs as well as putative metabolic products. Sample preparation based on solid-phase extraction and subsequent LC-MS/MS measurement allowed for detection limits of 1-20 ng/mL, intra- and interday precisions of between 2.4 and 13.2% and between 6.5 and 24.2%, respectively. Recoveries varied from 89 to 106%, and tests for ion suppression or enhancement effects were negative for all analytes. [figure: see text

  5. Androgen actions and the ovary.

    PubMed

    Walters, K A; Allan, C M; Handelsman, D J

    2008-03-01

    Although androgens and the androgen receptor (AR) have defining roles in male reproductive development and function, previously no role in female reproductive physiology beyond testosterone (T) as the precursor in estradiol (E(2)) biosynthesis was firmly established. Understanding the role and specific mechanisms of androgen action via the AR in the ovary has been limited by confusion on how to interpret results from pharmacological studies, because many androgens can be metabolized in vivo and in vitro to steroids that can also exert actions via the estrogen receptor (ESR). Recent genetic studies using mouse models with specific disruption of the Ar gene have highlighted the role that AR-mediated actions play in maintaining female fertility through key roles in the regulation of follicle health, development, and ovulation. Furthermore, these genetic studies have revealed that AR-mediated effects influence age-related female fertility, possibly via mechanisms acting predominantly at the hypothalamic-pituitary axis in a dose-dependent manner. This review focuses on combining the findings from pharmacological studies and novel genetic mouse models to unravel the roles of ovarian androgen actions in relation to female fertility and ovarian aging, as well as creating new insights into the role of androgens in androgen-associated reproductive disorders such as polycystic ovarian syndrome.

  6. Androgen receptors, sex behavior, and aggression.

    PubMed

    Cunningham, Rebecca L; Lumia, Augustus R; McGinnis, Marilyn Y

    2012-01-01

    Androgens are intricately involved in reproductive and aggressive behaviors, but the role of the androgen receptor in mediating these behaviors is less defined. Further, activity of the hypothalamic-pituitary-gonadal axis and hypothalamic-pituitary-adrenal axis can influence each other at the level of the androgen receptor. Knowledge of the mechanisms for androgens' effects on behaviors through the androgen receptor will guide future studies in elucidating male reproductive and aggressive behavior repertoires.

  7. Modulators of androgen and estrogen receptor activity.

    PubMed

    Clarke, Bart L; Khosla, Sundeep

    2010-01-01

    This review focuses on significant recent findings regarding modulators of androgen and estrogen receptor activity. Selective androgen receptor modulators (SARMs) interact with androgen receptors (ARs), and selective estrogen receptor modulators (SERMs) interact with estrogen receptors (ERs), with variable tissue selectivity. SERMs, which interact with both ERб and ERв in a tissue-specific manner to produce diverse outcomes in multiple tissues, continue to generate significant interest for clinical application. Development of SARMs for clinical application has been slower to date because of potential adverse effects, but these diverse compounds continue to be investigated for use in disorders in which modulation of the AR is important. SARMs have been investigated mostly at the basic and preclinical level to date, with few human clinical trials published. These compounds have been evaluated mostly for application in different stages of prostate cancer to date, but they hold promise for multiple other applications. Publication of the large STAR and RUTH clinical trials demonstrated that the SERMs tamoxifen and raloxifene have interesting similarities and differences in tissues that contain ERs. Lasofoxifene, bazedoxifene, and arzoxifene are newer SERMs that have been demonstrated in clinical trials to more potently increase bone mineral density and lower serum cholesterol values than tamoxifen or raloxifene. Both SARMs and SERMs hold great promise for therapeutic use in multiple disorders in which tissue-specific effects are mediated by their respective receptors.

  8. Identifying craniofacial features associated with prenatal exposure to androgens and testing their relationship with brain development.

    PubMed

    Marečková, Klára; Chakravarty, Mallar M; Lawrence, Claire; Leonard, Gabriel; Perusse, Daniel; Perron, Michel; Pike, Bruce G; Richer, Louis; Veillette, Suzanne; Pausova, Zdenka; Paus, Tomáš

    2015-11-01

    We used magnetic resonance (MR) images obtained in same-sex and opposite-sex dizygotic twins (n = 119, 8 years of age) to study possible effects of prenatal androgens on craniofacial features. Using a principal component analysis of 19 craniofacial landmarks placed on the MR images, we identified a principal component capturing craniofacial features that distinguished females with a presumed differential exposure to prenatal androgens by virtue of having a male (vs. a female) co-twin (Cohen's d = 0.76). Subsequently, we tested the possibility that this craniofacial "signature" of prenatal exposure to androgens predicts brain size, a known sexually dimorphic trait. In an independent sample of female adolescents (singletons; n = 462), we found that the facial signature predicts up to 8% of variance in brain size. These findings are consistent with the organizational effects of androgens on brain development and suggest that the facial signature derived in this study could complement other indirect measures of prenatal exposure to androgens.

  9. Androgens regulate Hedgehog signalling and proliferation in androgen-dependent prostate cells.

    PubMed

    Sirab, Nanor; Terry, Stéphane; Giton, Frank; Caradec, Josselin; Chimingqi, Mihelaiti; Moutereau, Stéphane; Vacherot, Francis; de la Taille, Alexandre; Kouyoumdjian, Jean-Claude; Loric, Sylvain

    2012-09-15

    Prostate cancer (PCa) is androgen sensitive in its development and progression to metastatic disease. Hedgehog (Hh) pathway activation is important in the initiation and growth of various carcinomas including PCa. We and others have observed aberrations of Hh pathway during the progression of PCa to the castration-resistant state. The involvement of androgen signalling in Hh pathway activation, however, remains largely elusive. Here we investigate the direct role of androgen signalling on Hh pathway. We examined the effect of Dihydrosterone (DHT), antiandrogen, bicalutamide, and Hh pathway inhibitor, KAAD-cyclopamine in four human prostate cell lines (two cancerous: LNCaP, VCaP, and two normal: PNT2 and PNT2-ARm which harbours a mutant version of androgen receptor (AR) that is commonly found in LNCaP). Cell proliferation as well as Hh pathway members (SHH, IHH, DHH, GLI, PTCH) mRNA expression levels were assessed. We showed that KAAD-cyclopamine decreased cell proliferation of DHT-stimulated LNCaP, VCaP and PNT2-ARm cells. SHH expression was found to be downregulated by DHT in all AR posititve cells. The negative effect of DHT on SHH expression was counteracted when cells were treated by bicalutamide. Importantly, KAAD-cyclopamine treatment seemed to inhibit AR activity. Moreover, bicalutamide as well as KAAD-cyclopamine treatments induced GLI and PTCH expression in VCaP and PNT2-ARm. Our results suggest that Hh pathway activity can be regulated by androgen signalling. Specifically, we show that the DHT-induced inhibition of Hh pathway is AR dependent. The mutual interaction between these two pathways might be important in the regulation of cell proliferation in PCa.

  10. Caffeic acid phenethyl ester induced cell cycle arrest and growth inhibition in androgen-independent prostate cancer cells via regulation of Skp2, p53, p21Cip1 and p27Kip1

    PubMed Central

    Su, Liang-Cheng; Jiang, Shih Sheng; Chan, Tzu-Min; Chang, Chung-Ho; Chen, Li-Tzong; Kung, Hsing-Jien; Wang, Horng-Dar; Chuu, Chih-Pin

    2015-01-01

    Prostate cancer (PCa) patients receiving the androgen ablation therapy ultimately develop recurrent castration-resistant prostate cancer (CRPC) within 1–3 years. Treatment with caffeic acid phenethyl ester (CAPE) suppressed cell survival and proliferation via induction of G1 or G2/M cell cycle arrest in LNCaP 104-R1, DU-145, 22Rv1, and C4–2 CRPC cells. CAPE treatment also inhibited soft agar colony formation and retarded nude mice xenograft growth of LNCaP 104-R1 cells. We identified that CAPE treatment significantly reduced protein abundance of Skp2, Cdk2, Cdk4, Cdk7, Rb, phospho-Rb S807/811, cyclin A, cyclin D1, cyclin H, E2F1, c-Myc, SGK, phospho-p70S6kinase T421/S424, phospho-mTOR Ser2481, phospho-GSK3α Ser21, but induced p21Cip1, p27Kip1, ATF4, cyclin E, p53, TRIB3, phospho-p53 (Ser6, Ser33, Ser46, Ser392), phospho-p38 MAPK Thr180/Tyr182, Chk1, Chk2, phospho-ATM S1981, phospho-ATR S428, and phospho-p90RSK Ser380. CAPE treatment decreased Skp2 and Akt1 protein expression in LNCaP 104-R1 tumors as compared to control group. Overexpression of Skp2, or siRNA knockdown of p21Cip1, p27Kip1, or p53 blocked suppressive effect of CAPE treatment. Co-treatment of CAPE with PI3K inhibitor LY294002 or Bcl-2 inhibitor ABT737 showed synergistic suppressive effects. Our finding suggested that CAPE treatment induced cell cycle arrest and growth inhibition in CRPC cells via regulation of Skp2, p53, p21Cip1, and p27Kip1. PMID:25788262

  11. Androgen replacement therapy: present and future.

    PubMed

    Gooren, Louis J G; Bunck, Mathijs C M

    2004-01-01

    The major goal of androgen substitution is to replace testosterone at levels as close to physiological levels as is possible. For some androgen-dependent functions testosterone is a pro-hormone, peripherally converted to 5alpha-dihydrotestosterone (DHT) and 17beta-estradiol (E2), of which the levels preferably should be within normal physiological ranges. Furthermore, androgens should have a good safety profile without adverse effects on the prostate, serum lipids, liver or respiratory function, and they must be convenient to use and patient-friendly, with a relative independence from medical services. Natural testosterone is viewed as the best androgen for substitution in hypogonadal men. The reason behind the selection is that testosterone can be converted to DHT and E2, thus developing the full spectrum of testosterone activities in long-term substitution. The mainstays of testosterone substitution are parenteral testosterone esters (testosterone enantate and testosterone cipionate) administered every 2-3 weeks. A major disadvantage is the strongly fluctuating levels of plasma testosterone, which are not in the physiological range at least 50% of the time. Also, the generated plasma E2 is usually supraphysiological. A major improvement is parenteral testosterone undecanoate producing normal plasma levels of testosterone for 12 weeks, with normal plasma levels of DHT and E2 also. Subcutaneous testosterone implants provide the patient, depending on the dose of implants, with normal plasma testosterone for 3-6 months. However, their use is not widespread. Oral testosterone undecanoate dissolved in castor oil bypasses the liver via its lymphatic absorption. At a dosage of 80 mg twice daily, plasma testosterone levels are largely in the normal range, but plasma DHT tends to be elevated. For two decades transdermal testosterone preparations have been available and have an attractive pharmacokinetic profile. Scrotal testosterone patches generate supraphysiological

  12. New steroidal 17β-carboxy derivatives present anti-5α-reductase activity and anti-proliferative effects in a human androgen-responsive prostate cancer cell line.

    PubMed

    Amaral, Cristina; Varela, Carla; Correia-da-Silva, Georgina; Tavares da Silva, Elisiário; Carvalho, Rui A; Costa, Saul C P; Cunha, Sara C; Fernandes, José O; Teixeira, Natércia; Roleira, Fernanda M F

    2013-11-01

    The androgens testosterone (T) and dihydrotestosterone (DHT), besides playing an important role in prostate development and growth, are also responsible for the development and progression of benign prostate hyperplasia (BPH) and prostate cancer. Therefore, the actions of these hormones can be antagonized by preventing the irreversible conversion of T into DHT by inhibiting 5α-reductase (5α-R). This has been a useful therapeutic approach for the referred diseases and can be achieved by using 5α-reductase inhibitors (RIs). Steroidal RIs, finasteride and dutasteride, are used in clinic for BPH treatment and were also proposed for chemoprevention of prostate cancer. Nevertheless, due to the increase in bone and muscle loss, impotency and occurrence of high-grade prostate tumours, it is important to seek for other potent and specific molecules with lower side effects. In the present work, we designed and synthesized steroids with the 3-keto-Δ(4) moiety in the A-ring, as in the 5α-R substrate T, and with carboxamide, carboxyester or carboxylic acid functions at the C-17β position. The inhibitory 5α-R activity, in human prostate microsomes, as well as the anti-proliferative effects of the most potent compounds, in a human androgen-responsive prostate cancer cell line (LNCaP cells), were investigated. Our results showed that steroids 3, 4 and 5 are good RIs, which suggest that C-17β lipophylic amides favour 5α-R inhibition. Moreover, these steroids induce a decrease in cell viability of stimulated LNCaP cells, in a 5α-R dependent-manner, similarly to finasteride. PMID:23933094

  13. Human Brain Expansion during Evolution Is Independent of Fire Control and Cooking.

    PubMed

    Cornélio, Alianda M; de Bittencourt-Navarrete, Ruben E; de Bittencourt Brum, Ricardo; Queiroz, Claudio M; Costa, Marcos R

    2016-01-01

    What makes humans unique? This question has fascinated scientists and philosophers for centuries and it is still a matter of intense debate. Nowadays, human brain expansion during evolution has been acknowledged to explain our empowered cognitive capabilities. The drivers for such accelerated expansion remain, however, largely unknown. In this sense, studies have suggested that the cooking of food could be a pre-requisite for the expansion of brain size in early hominins. However, this appealing hypothesis is only supported by a mathematical model suggesting that the increasing number of neurons in the brain would constrain body size among primates due to a limited amount of calories obtained from diets. Here, we show, by using a similar mathematical model, that a tradeoff between body mass and the number of brain neurons imposed by dietary constraints during hominin evolution is unlikely. Instead, the predictable number of neurons in the hominin brain varies much more in function of foraging efficiency than body mass. We also review archeological data to show that the expansion of the brain volume in the hominin lineage is described by a linear function independent of evidence of fire control, and therefore, thermal processing of food does not account for this phenomenon. Finally, we report experiments in mice showing that thermal processing of meat does not increase its caloric availability in mice. Altogether, our data indicate that cooking is neither sufficient nor necessary to explain hominin brain expansion. PMID:27199631

  14. Human Brain Expansion during Evolution Is Independent of Fire Control and Cooking

    PubMed Central

    Cornélio, Alianda M.; de Bittencourt-Navarrete, Ruben E.; de Bittencourt Brum, Ricardo; Queiroz, Claudio M.; Costa, Marcos R.

    2016-01-01

    What makes humans unique? This question has fascinated scientists and philosophers for centuries and it is still a matter of intense debate. Nowadays, human brain expansion during evolution has been acknowledged to explain our empowered cognitive capabilities. The drivers for such accelerated expansion remain, however, largely unknown. In this sense, studies have suggested that the cooking of food could be a pre-requisite for the expansion of brain size in early hominins. However, this appealing hypothesis is only supported by a mathematical model suggesting that the increasing number of neurons in the brain would constrain body size among primates due to a limited amount of calories obtained from diets. Here, we show, by using a similar mathematical model, that a tradeoff between body mass and the number of brain neurons imposed by dietary constraints during hominin evolution is unlikely. Instead, the predictable number of neurons in the hominin brain varies much more in function of foraging efficiency than body mass. We also review archeological data to show that the expansion of the brain volume in the hominin lineage is described by a linear function independent of evidence of fire control, and therefore, thermal processing of food does not account for this phenomenon. Finally, we report experiments in mice showing that thermal processing of meat does not increase its caloric availability in mice. Altogether, our data indicate that cooking is neither sufficient nor necessary to explain hominin brain expansion. PMID:27199631

  15. Cue-independent memory impairment by reactivation-coupled interference in human declarative memory.

    PubMed

    Zhu, Zijian; Wang, Yingying; Cao, Zhijun; Chen, Biqing; Cai, Huaqian; Wu, Yanhong; Rao, Yi

    2016-10-01

    Memory is a dynamic process. While memory becomes increasingly resistant to interference after consolidation, a brief reactivation renders it unstable again. Previous studies have shown that interference, when applied upon reactivation, impairs the consolidated memory, presumably by disrupting the reconsolidation of the memory. However, attempts have failed in disrupting human declarative memory, raising a question about whether declarative memory becomes unstable upon reactivation. Here, we used a double-cue/one-target paradigm, which associated the same target with two different cues in initial memory formation. Only one cue/target association was later reactivated and treated with behavioral interference. Our results showed, for the first time, that reactivation-coupled interference caused cue-independent memory impairment that generalized to other cues associated with the memory. Critically, such memory impairment appeared immediately after interference, before the reconsolidation process was completed, suggesting that common manipulations of reactivation-coupled interference procedures might disrupt other processes in addition to the reconsolidation process in human declarative memory.

  16. The independent roles of temperature and thermal perception in the control of human thermoregulatory behavior.

    PubMed

    Schlader, Zachary J; Simmons, Shona E; Stannard, Stephen R; Mündel, Toby

    2011-05-01

    The present study independently evaluated temperature and thermal perception as controllers of thermoregulatory behavior in humans. This was accomplished using a self-paced exercise and heat stress model in which twelve physically active male subjects exercised at a constant subjective rating of perceived exertion (16, 'hard--very hard') while their face was thermally and non-thermally cooled, heated, or left alone (control trial). Thermal cooling and heating were achieved via forced convection, while non-thermal cooling and heating were accomplished via the topical application of menthol and capsaicin solutions. Evidence for thermoregulatory behavior was defined in terms of self-selected exercise intensity, and thus exercise work output. The results indicate that, in the absence of changes in temperature, non-thermal cooling and warming elicited thermal sensory and discomfort sensations similar to those observed during thermal cooling and warming. Furthermore, the perception of effort was maintained throughout exercise in all trials, while the initial and final exercise intensities were also similar. Thermal and non-thermal cooling resulted in the highest work output, while thermal warming the lowest. Non-thermal warming and control trials were similar. Heart rate, mean skin and core (rectal) temperatures, and whole body and local (neck) sweat rates were similar between all trials. These data indicate that changes in temperature are not a requirement for the initiation of thermoregulatory behavior in humans. Rather, thermal sensation and thermal discomfort are capable behavioral controllers.

  17. Independent component analysis: mining microarray data for fundamental human gene expression modules.

    PubMed

    Engreitz, Jesse M; Daigle, Bernie J; Marshall, Jonathan J; Altman, Russ B

    2010-12-01

    As public microarray repositories rapidly accumulate gene expression data, these resources contain increasingly valuable information about cellular processes in human biology. This presents a unique opportunity for intelligent data mining methods to extract information about the transcriptional modules underlying these biological processes. Modeling cellular gene expression as a combination of functional modules, we use independent component analysis (ICA) to derive 423 fundamental components of human biology from a 9395-array compendium of heterogeneous expression data. Annotation using the Gene Ontology (GO) suggests that while some of these components represent known biological modules, others may describe biology not well characterized by existing manually-curated ontologies. In order to understand the biological functions represented by these modules, we investigate the mechanism of the preclinical anti-cancer drug parthenolide (PTL) by analyzing the differential expression of our fundamental components. Our method correctly identifies known pathways and predicts that N-glycan biosynthesis and T-cell receptor signaling may contribute to PTL response. The fundamental gene modules we describe have the potential to provide pathway-level insight into new gene expression datasets.

  18. Contact-independent cell death of human microglial cells due to pathogenic Naegleria fowleri trophozoites.

    PubMed

    Kim, Jong-Hyun; Kim, Daesik; Shin, Ho-Joon

    2008-12-01

    Free-living Naegleria fowleri leads to a fatal infection known as primary amebic meningoencephalitis in humans. Previously, the target cell death could be induced by phagocytic activity of N. fowleri as a contact-dependent mechanism. However, in this study we investigated the target cell death under a non-contact system using a tissue-culture insert. The human microglial cells, U87MG cells, co-cultured with N. fowleri trophozoites for 30 min in a non-contact system showed morphological changes such as the cell membrane destruction and a reduction in the number. By fluorescence-activated cell sorter (FACS) analysis, U87MG cells co-cultured with N. fowleri trophozoites in a non-contact system showed a significant increase of apoptotic cells (16%) in comparison with that of the control or N. fowleri lysate. When U87MG cells were co-cultured with N. fowleri trophozoites in a non-contact system for 30 min, 2 hr, and 4 hr, the cytotoxicity of amebae against target cells was 40.5, 44.2, and 45.6%, respectively. By contrast, the cytotoxicity of non-pathogenic N. gruberi trophozoites was 10.2, 12.4, and 13.2%, respectively. These results suggest that the molecules released from N. fowleri in a contact-independent manner as well as phagocytosis in a contact-dependent manner may induce the host cell death.

  19. Does field independence predict visuo-spatial abilities underpinning human navigation? Behavioural evidence.

    PubMed

    Boccia, Maddalena; Piccardi, Laura; Di Marco, Mariangela; Pizzamiglio, Luigi; Guariglia, Cecilia

    2016-10-01

    Field independence (FI) has been defined as the extent to which the individual perceives part of a field as discrete from the surrounding field, rather than embedded in the field. It has been proposed to represent a relatively stable pattern in individuals' predisposition towards information processing. In the present study, we assessed the effect of FI on skills underpinning human navigation. Fifty Healthy individuals took part in this study. FI has been assessed by using the group embedded figures test (GEFT). Participants were also asked to perform several visuo-spatial orientation tasks, including the perspective taking/spatial orientation test (PTSOT), the mental rotation task (MRT) and the vividness task, as well as the Santa Barbara Sense of Direction Scale, a self-reported questionnaire, which has been found to predict environmental spatial orientation ability. We found that performances on the GEFT significantly predicted performances on the PTSOT and the MRT. This result supports the idea that FI predicts human navigation. PMID:27225254

  20. DIETARY PHYTOCHEMICALS INDUCE p53- AND CASPASE-INDEPENDENT CELL DEATH IN HUMAN NEUROBLASTOMA CELLS

    PubMed Central

    Sukumari-Ramesh, Sangeetha; Bentley, J. Nicole; Laird, Melissa D.; Singh, Nagendra; Vender, John R.; Dhandapani, Krishnan M

    2013-01-01

    Neuroblastoma (NB) is the most prevalent pediatric solid tumor and a leading cause of cancer-related death in children. In the present study, a novel cytotoxic role for the dietary compounds, curcumin, andrographolide, wedelolactone, dibenzoylmethane, and tanshinone IIA was identified in human S-type NB cells, SK-N-AS and SK-N-BE(2). Mechanistically, cell death appeared apoptotic by flow cytometry; however, these effects proceeded independently from both caspase-3 and p53 activation, as assessed by both genetic (shRNA) and pharmacological approaches. Notably, cell death induced by both curcumin and andrographolide was associated with decreased NFκB activity and a reduction in Bcl-2 and Bcl-xL expression. Finally, curcumin and andrographolide increased cytotoxicity following co-treatment with either cisplatin or doxorubicin, two chemotherapeutic agents widely used in the clinical management of NB. Coupled with the documented safety in humans, dietary compounds may represent a potential adjunct therapy for NB. PMID:21704149

  1. Cue-independent memory impairment by reactivation-coupled interference in human declarative memory.

    PubMed

    Zhu, Zijian; Wang, Yingying; Cao, Zhijun; Chen, Biqing; Cai, Huaqian; Wu, Yanhong; Rao, Yi

    2016-10-01

    Memory is a dynamic process. While memory becomes increasingly resistant to interference after consolidation, a brief reactivation renders it unstable again. Previous studies have shown that interference, when applied upon reactivation, impairs the consolidated memory, presumably by disrupting the reconsolidation of the memory. However, attempts have failed in disrupting human declarative memory, raising a question about whether declarative memory becomes unstable upon reactivation. Here, we used a double-cue/one-target paradigm, which associated the same target with two different cues in initial memory formation. Only one cue/target association was later reactivated and treated with behavioral interference. Our results showed, for the first time, that reactivation-coupled interference caused cue-independent memory impairment that generalized to other cues associated with the memory. Critically, such memory impairment appeared immediately after interference, before the reconsolidation process was completed, suggesting that common manipulations of reactivation-coupled interference procedures might disrupt other processes in addition to the reconsolidation process in human declarative memory. PMID:27389345

  2. An Update on Plant Derived Anti-Androgens

    PubMed Central

    Grant, Paul; Ramasamy, Shamin

    2012-01-01

    Anti-androgens are an assorted group of drugs and compounds that reduce the levels or activity of androgen hormones within the human body. Disease states in which this is relevant include polycystic ovarian syndrome, hirsutism, acne, benign prostatic hyperplasia, and endocrine related cancers such as carcinoma of the prostate. We provide an overview and discussion of the use of anti-androgen medications in clinical practice and explore the increasing recognition of the benefits of plant-derived anti-androgens, for example, spearmint tea in the management of PCOS, for which some evidence about efficacy is beginning to emerge. Other agents covered include red reishi, which has been shown to reduce levels 5-alpha reductase, the enzyme that facilitates conversion of testosterone to dihydrotestosterone (DHT); licorice, which has phytoestrogen effects and reduces testosterone levels; Chinese peony, which promotes the aromatization of testosterone into estrogen; green tea, which contains epigallocatechins and also inhibits 5-alpha reductase, thereby reducing the conversion of normal testosterone into the more potent DHT; black cohosh, which has been shown to kill both androgenresponsive and non-responsive human prostate cancer cells; chaste tree, which has a reduces prolactin from the anterior pituitary; and saw palmetto extract, which is used as an anti-androgen although it shown no difference in comparison to placebo in clinical trials. PMID:23843810

  3. An update on plant derived anti-androgens.

    PubMed

    Grant, Paul; Ramasamy, Shamin

    2012-01-01

    Anti-androgens are an assorted group of drugs and compounds that reduce the levels or activity of androgen hormones within the human body. Disease states in which this is relevant include polycystic ovarian syndrome, hirsutism, acne, benign prostatic hyperplasia, and endocrine related cancers such as carcinoma of the prostate. We provide an overview and discussion of the use of anti-androgen medications in clinical practice and explore the increasing recognition of the benefits of plant-derived anti-androgens, for example, spearmint tea in the management of PCOS, for which some evidence about efficacy is beginning to emerge. Other agents covered include red reishi, which has been shown to reduce levels 5-alpha reductase, the enzyme that facilitates conversion of testosterone to dihydrotestosterone (DHT); licorice, which has phytoestrogen effects and reduces testosterone levels; Chinese peony, which promotes the aromatization of testosterone into estrogen; green tea, which contains epigallocatechins and also inhibits 5-alpha reductase, thereby reducing the conversion of normal testosterone into the more potent DHT; black cohosh, which has been shown to kill both androgenresponsive and non-responsive human prostate cancer cells; chaste tree, which has a reduces prolactin from the anterior pituitary; and saw palmetto extract, which is used as an anti-androgen although it shown no difference in comparison to placebo in clinical trials. PMID:23843810

  4. Activated human neutrophil response to perfluorocarbon nanobubbles: oxygen-dependent and -independent cytotoxic responses.

    PubMed

    Hwang, Tsong-Long; Fang, Chia-Lang; Al-Suwayeh, Saleh A; Yang, Li-Jia; Fang, Jia-You

    2011-06-10

    Nanobubbles, a type of nanoparticles with acoustically active properties, are being utilized as diagnostic and therapeutic nanoparticles to better understand, detect, and treat human diseases. The objective of this work was to prepare different nanobubble formulations and investigate their physicochemical characteristics and toxic responses to N-formyl-methionyl-leucyl-phenylalanine (fMLP)-activated human neutrophils. The nanobubbles were prepared using perfluoropentane and coconut oil as the respective core and shell, with soybean phosphatidylcholine (SPC) and/or cationic surfactants as the interfacial layers. The cytotoxic effect of the nanobubbles on neutrophils was determined by extracellular O₂(.)⁻ release, intracellular reactive oxygen species (ROS), lactate dehydrogenase (LDH), and elastase release. Particle sizes of the nanobubbles with different percentages of perfluorocarbon, oil, and surfactants in ranged 186-432 nm. The nanobubbles were demonstrated to inhibit the generation of superoxide and intracellular ROS. The cytotoxicity of nanobubbles may be mainly associated with membrane damage, as indicated by the high LDH leakage. Systems with Forestall (FE), a cationic surfactant, or higher SPC contents exhibited the greatest LDH release by 3-fold compared to the control. The further addition of an oil component reduced the cytotoxicity induced by the nanobubbles. Exposure to most of the nanobubble formulations upregulated elastase release by activated neutrophils. Contrary to this result, stearylamine (SA)-containing systems slightly but significantly suppressed elastase release. FE and SA in a free form caused stronger responses by neutrophils than when they were incorporated into nanobubbles. In summary, exposure to nanobubbles resulted in a formulation-dependent toxicity toward human neutrophils that was associated with both oxygen-dependent and -independent pathways. Clinicians should therefore exercise caution when using nanobubbles in patients

  5. In vitro human embryonic stem cell hematopoiesis mimics MYB-independent yolk sac hematopoiesis.

    PubMed

    Vanhee, Stijn; De Mulder, Katrien; Van Caeneghem, Yasmine; Verstichel, Greet; Van Roy, Nadine; Menten, Björn; Velghe, Imke; Philippé, Jan; De Bleser, Dominique; Lambrecht, Bart N; Taghon, Tom; Leclercq, Georges; Kerre, Tessa; Vandekerckhove, Bart

    2015-02-01

    Although hematopoietic precursor activity can be generated in vitro from human embryonic stem cells, there is no solid evidence for the appearance of multipotent, self-renewing and transplantable hematopoietic stem cells. This could be due to short half-life of hematopoietic stem cells in culture or, alternatively, human embryonic stem cell-initiated hematopoiesis may be hematopoietic stem cell-independent, similar to yolk sac hematopoiesis, generating multipotent progenitors with limited expansion capacity. Since a MYB was reported to be an excellent marker for hematopoietic stem cell-dependent hematopoiesis, we generated a MYB-eGFP reporter human embryonic stem cell line to study formation of hematopoietic progenitor cells in vitro. We found CD34(+) hemogenic endothelial cells rounding up and developing into CD43(+) hematopoietic cells without expression of MYB-eGFP. MYB-eGFP(+) cells appeared relatively late in embryoid body cultures as CD34(+)CD43(+)CD45(-/lo) cells. These MYB-eGFP(+) cells were CD33 positive, proliferated in IL-3 containing media and hematopoietic differentiation was restricted to the granulocytic lineage. In agreement with data obtained on murine Myb(-/-) embryonic stem cells, bright eGFP expression was observed in a subpopulation of cells, during directed myeloid differentiation, which again belonged to the granulocytic lineage. In contrast, CD14(+) macrophage cells were consistently eGFP(-) and were derived from eGFP-precursors only. In summary, no evidence was obtained for in vitro generation of MYB(+) hematopoietic stem cells during embryoid body cultures. The observed MYB expression appeared late in culture and was confined to the granulocytic lineage.

  6. Neural Processes in the Human Temporoparietal Cortex Separated by Localized Independent Component Analysis.

    PubMed

    Igelström, Kajsa M; Webb, Taylor W; Graziano, Michael S A

    2015-06-24

    The human temporoparietal junction (TPJ) is a topic of intense research. Imaging studies have identified TPJ activation in association with many higher-order functions such as theory-of-mind, episodic memory, and attention, causing debate about the distribution of different processes. One major challenge is the lack of consensus about the anatomical location and extent of the TPJ. Here, we address this problem using data-driven analysis to test the hypothesis that the bilateral TPJ can be parcellated into subregions. We applied independent component analysis (ICA) to task-free fMRI data within a local region around the bilateral TPJ, iterating the ICA at multiple model orders and in several datasets. The localized analysis allowed finer separation of processes and the use of multiple dimensionalities provided qualitative information about lateralization. We identified four subdivisions that were bilaterally symmetrical and one that was right biased. To test whether the independent components (ICs) reflected true subdivisions, we performed functional connectivity analysis using the IC coordinates as seeds. This confirmed that the subdivisions belonged to distinct networks. The right-biased IC was connected with a network often associated with attentional processing. One bilateral subdivision was connected to sensorimotor regions and another was connected to auditory regions. One subdivision that presented as distinct left- and right-biased ICs was connected to frontoparietal regions. Another subdivision that also had left- and right-biased ICs was connected to social or default mode networks. Our results show that the TPJ in both hemispheres hosts multiple neural processes with connectivity patterns consistent with well developed specialization and lateralization. PMID:26109666

  7. Human Papillomavirus as an Independent Predictor in Oral Squamous Cell Cancer

    PubMed Central

    Zhao, Dan; Xu, Qin-gan; Chen, Xin-ming; Fan, Ming-wen

    2009-01-01

    Aim There is an increasing evidence for the role of high risk human papillomavirus (HPV) in the pathogenesis of oral squamous cell carcinoma (OSCC). The purpose of this study is to evaluate the relevance of HPV infection to the survival and prognosis of OSCC. Methodology Fifty-two patients with OSCC were followed from 4 to 88 months with a median of 50.7 months. HPV DNA was identified in formalin-fixed, paraffin-embedded tumor specimens by nested PCR with MY09/MY11 and GP5+/GP6+ primer pairs and the HPV genotype was determined by direct DNA sequencing. Association between the HPV status and risk factors for cancer as well as tumor-host characteristics were analyzed. Survival curves were calculated by the Kaplan-Meier method and analyzed using the log-rank test. Results HPV was found in 40.4% of the tumors with HPV16 accounting for 63.5%, HPV18 for 30.8%, HPV6 for 3.9% and HPV11 for 1.8%. No infection with more than one HPV genotype was detected. HPV infection was significantly associated with poor histological grade, TNM stage I–II, alcohol usage and no smoking status. Multi-variate analysis showed that HPV had an independent prognostic effect on the overall survival after adjusting other confounding factors such as histological grade, TNM stage and tobacco usage. The presence of HPV was significantly correlated with a better survival in patients with OSCC. Conclusion HPV infection can act as an independent predictor for the survival and prognosis of OSCC. PMID:20695077

  8. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth

    PubMed Central

    Opoku-Acheampong, Alexander B.; Penugonda, Kavitha; Lindshield, Brian L.

    2016-01-01

    Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth. PMID:27272436

  9. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth.

    PubMed

    Opoku-Acheampong, Alexander B; Penugonda, Kavitha; Lindshield, Brian L

    2016-01-01

    Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth. PMID:27272436

  10. Coibamide A Induces mTOR-Independent Autophagy and Cell Death in Human Glioblastoma Cells

    PubMed Central

    Hau, Andrew M.; Greenwood, Jeffrey A.; Löhr, Christiane V.; Serrill, Jeffrey D.; Proteau, Philip J.; Ganley, Ian G.; McPhail, Kerry L.; Ishmael, Jane E.

    2013-01-01

    Coibamide A is an N-methyl-stabilized depsipeptide that was isolated from a marine cyanobacterium as part of an International Cooperative Biodiversity Groups (ICBG) program based in Panama. Previous testing of coibamide A in the NCI in vitro 60 cancer cell line panel revealed a potent anti-proliferative response and “COMPARE-negative” profile indicative of a unique mechanism of action. We report that coibamide A is a more potent and efficacious cytotoxin than was previously appreciated, inducing concentration- and time-dependent cytotoxicity (EC50<100 nM) in human U87-MG and SF-295 glioblastoma cells and mouse embryonic fibroblasts (MEFs). This activity was lost upon linearization of the molecule, highlighting the importance of the cyclized structure for both anti-proliferative and cytotoxic responses. We show that coibamide A induces autophagosome accumulation in human glioblastoma cell types and MEFs via an mTOR-independent mechanism; no change was observed in the phosphorylation state of ULK1 (Ser-757), p70 S6K1 (Thr-389), S6 ribosomal protein (Ser-235/236) and 4EBP-1 (Thr-37/46). Coibamide A also induces morphologically and biochemically distinct forms of cell death according to cell type. SF-295 glioblastoma cells showed caspase-3 activation and evidence of apoptotic cell death in a pattern that was also seen in wild-type and autophagy-deficient (ATG5-null) MEFs. In contrast, cell death in U87-MG glioblastoma cells was characterized by extensive cytoplasmic vacuolization and lacked clear apoptotic features. Cell death was attenuated, but still triggered, in Apaf-1-null MEFs lacking a functional mitochondria-mediated apoptotic pathway. From the study of ATG5-null MEFs we conclude that a conventional autophagy response is not required for coibamide A-induced cell death, but likely occurs in dying cells in response to treatment. Coibamide A represents a natural product scaffold with potential for the study of mTOR-independent signaling and cell death

  11. Androgen suppresses the proliferation of androgen receptor-positive castration-resistant prostate cancer cells via inhibition of Cdk2, CyclinA, and Skp2.

    PubMed

    Kokontis, John M; Lin, Hui-Ping; Jiang, Shih Sheng; Lin, Ching-Yu; Fukuchi, Junichi; Hiipakka, Richard A; Chung, Chi-Jung; Chan, Tzu-Min; Liao, Shutsung; Chang, Chung-Ho; Chuu, Chih-Pin

    2014-01-01

    The majority of prostate cancer (PCa) patient receiving androgen ablation therapy eventually develop castration-resistant prostate cancer (CRPC). We previously reported that androgen treatment suppresses Skp2 and c-Myc through androgen receptor (AR) and induced G1 cell cycle arrest in androgen-independent LNCaP 104-R2 cells, a late stage CRPC cell line model. However, the mechanism of androgenic regulation of Skp2 in CRPC cells was not fully understood. In this study, we investigated the androgenic regulation of Skp2 in two AR-positive CRPC cell line models, the LNCaP 104-R1 and PC-3AR Cells. The former one is an early stage androgen-independent LNCaP cells, while the later one is PC-3 cells re-expressing either wild type AR or mutant LNCaP AR. Proliferation of LNCaP 104-R1 and PC-3AR cells is not dependent on but is suppressed by androgen. We observed in this study that androgen treatment reduced protein expression of Cdk2, Cdk7, Cyclin A, cyclin H, Skp2, c-Myc, and E2F-1; lessened phosphorylation of Thr14, Tyr15, and Thr160 on Cdk2; decreased activity of Cdk2; induced protein level of p27(Kip1); and caused G1 cell cycle arrest in LNCaP 104-R1 cells and PC-3AR cells. Overexpression of Skp2 protein in LNCaP 104-R1 or PC-3AR cells partially blocked accumulation of p27(Kip1) and increased Cdk2 activity under androgen treatment, which partially blocked the androgenic suppressive effects on proliferation and cell cycle. Analyzing on-line gene array data of 214 normal and PCa samples indicated that gene expression of Skp2, Cdk2, and cyclin A positively correlates to each other, while Cdk7 negatively correlates to these genes. These observations suggested that androgen suppresses the proliferation of CRPC cells partially through inhibition of Cyclin A, Cdk2, and Skp2.

  12. Undecylprodigiosin selectively induces apoptosis in human breast carcinoma cells independent of p53

    SciTech Connect

    Ho, T.-F.; Ma, C.-J.; Lu, C.-H.; Tsai, Yo-Ting; Wei, Y.-H.; Chang, J.-S.; Lai, J.-K.; Cheuh, Pin-Ju; Yeh, C.-T.; Tang, P.-C.; Jingua, T.C.; Ko, J.-L.; Liu, F.-S.; Yen, H.E.

    2007-12-15

    Undecylprodigiosin (UP) is a bacterial bioactive metabolite produced by Streptomyces and Serratia. In this study, we explored the anticancer effect of UP. Human breast carcinoma cell lines BT-20, MCF-7, MDA-MB-231 and T47D and one nonmalignant human breast epithelial cell line, MCF-10A, were tested in this study. We found that UP exerted a potent cytotoxicity against all breast carcinoma cell lines in a dose- and time-dependent manner. In contrast, UP showed limited toxicity to MCF-10A cells, indicating UP's cytotoxic effect is selective for malignant cells. UP's cytotoxic effect was due to apoptosis, as confirmed by positive TUNEL signals, annexin V-binding, caspase 9 activation and PARP cleavage. Notably, UP-induced apoptosis was blocked by the pan-caspase inhibitor z-VAD.fmk, further indicating the involvement of caspase activity. Moreover, UP caused a marked decrease of the levels of antiapoptotic BCL-X{sub L}, Survivin and XIAP while enhancing the levels of proapoptotic BIK, BIM, MCL-1S and NOXA, consequently favoring induction of apoptosis. Additionally, we found that cells with functional p53 (MCF-7, T47D) or mutant p53 (BT-20, MDA-MB-231) were both susceptible to UP's cytotoxicity. Importantly, UP was able to induce apoptosis in MCF-7 cells with p53 knockdown by RNA interference, confirming the dispensability of p53 in UP-induced apoptosis. Overall, our results establish that UP induces p53-independent apoptosis in breast carcinoma cells with no marked toxicity to nonmalignant cells, raising the possibility of its use as a new chemotherapeutic drug for breast cancer irrespective of p53 status.

  13. The mRNA of human cytoplasmic arginyl-tRNA synthetase recruits prokaryotic ribosomes independently.

    PubMed

    Yang, Fang; Ji, Quan-Quan; Ruan, Liang-Liang; Ye, Qing; Wang, En-Duo

    2014-07-25

    There are two isoforms of cytoplasmic arginyl-tRNA synthetase (hcArgRS) in human cells. The long form is a component of the multiple aminoacyl-tRNA synthetase complex, and the other is an N-terminal truncated form (NhcArgRS), free in the cytoplasm. It has been shown that the two forms of ArgRS arise from alternative translational initiation in a single mRNA. The short form is produced from the initiation at a downstream, in-frame AUG start codon. Interestingly, our data suggest that the alternative translational initiation of hcArgRS mRNA also takes place in Escherichia coli transformants. When the gene encoding full-length hcArgRS was overexpressed in E. coli, two forms of hcArgRS were observed. The N-terminal sequencing experiment identified that the short form was identical to the NhcArgRS in human cytoplasm. By constructing a bicistronic system, our data support that the mRNA encoding the N-terminal extension of hcArgRS has the capacity of independently recruiting E. coli ribosomes. Furthermore, two critical elements for recruiting prokaryotic ribosomes were identified, the “AGGA” core of the Shine-Dalgarno sequence and the “A-rich” sequence located just proximal to the alternative in-frame initiation site. Although the mechanisms of prokaryotic and eukaryotic translational initiation are distinct, they share some common features. The ability of the hcArgRS mRNA to recruit the prokaryotic ribosome may provide clues for shedding light on the mechanism of alternative translational initiation of hcArgRS mRNA in eukaryotic cells.

  14. Ultraviolet radiation acts as an independent mitogen for normal human melanocytes in culture

    SciTech Connect

    Libow, L.F.; Scheide, S.; DeLeo, V.A.

    1988-01-01

    Identification of growth factors for normal human melanocytes has been significantly aided by the recent development of in vitro culture systems for this cell. Utilizing such a system, we studied the effect of ultraviolet radiation (UVR) on both melanocyte growth and melanization by incorporation of 3H-thymidine and 3H-L-dihydroxyphenylalanine (3H-DOPA), respectively. 3H-thymidine incorporation was found to be significantly stimulated during the first 24 h following a single irradiation. 3H-DOPA incorporation was stimulated after a delay of 2 days postirradiation. Whereas UVR has long been known to induce melanocyte proliferation in vivo, these studies show that UVR can act as a mitogenic stimulus for this cell independent of the cutaneous environment. UVR can thus be added to a growing list of growth factors for epidermal pigment cells and is the only physical agent conclusively shown to act as a mitogen. Included in this list are substances that act via stimulation of the CAMP-kinase or protein kinase systems such as cholera toxin and phorbol esters. UVR is postulated to induce melanocyte proliferation by modulation of these second messenger pathways. With recent evidence linking growth factors, oncogenes and malignant transformation, this study supports the association between UVR exposure and the development of malignant melanoma, and suggests mechanisms whereby UVR may contribute to malignant transformation of this cell.

  15. Proliferation-independent growth factor modulation of the radiation sensitivity of human prostate cells

    SciTech Connect

    Howard, S.P.; Groch, K.M.; Lindstrom, M.J.

    1995-08-01

    The survival of human prostatic epithelial cells irradiated in different physiological states is reported. Exponentially growing cells and contact-inhibited cells grown and irradiated in the presence of the growth factors epidermal growth factor (EGF) and bovine pituitary extract (bPE) had overlapping radiation dose-cell survival curves. However, when EGF and bPE were removed from exponentially growing cells before irradiation, an increase in radiosensitivity was observed if the cells were replated into medium containing growth factors (EGF and bPE) immediately after irradiation. Treating cells with the nonspecific growth factor receptor antagonist suramin had similar effects as did growth factor deprivation. In contrast, when growth factor-deprived cells were maintained in this same medium for 12 h postirradiation, an increase in radiation survival was observed. This increase in survival is attributed to the repair of potentially lethal damage (PLD). Both the increase in radiosensitivity induced by deprivation of growth factor before irradiation and the repair of PLD caused by deprivation of growth factor after irradiation were independent of changes in cellular proliferation. 22 refs., 1 fig., 2 tab.

  16. Human CST has independent functions during telomere duplex replication and C-strand fill-in

    PubMed Central

    Wang, Feng; Stewart, Jason A.; Kasbek, Christopher; Zhao, Yong; Wright, Woodring E.; Price, Carolyn M.

    2012-01-01

    Summary Human CST (CTC1-STN1-TEN1) is an RPA-like complex that is needed for efficient replication through the telomere duplex and genome-wide replication restart after fork stalling. Here we show that STN1/CST has a second function in telomere replication during G-overhang maturation. Analysis of overhang structure after STN1 depletion revealed normal kinetics for telomerase-mediated extension in S-phase but a delay in subsequent overhang shortening. This delay resulted from a defect in C-strand fill-in. Short telomeres exhibited the fill-in defect but normal telomere duplex replication, indicating that STN1/CST functions independently in these processes. Our work also indicates that the requirement for STN1/CST in telomere duplex replication correlates with increasing telomere length and replication stress. Our results provide the first direct evidence that STN1/CST participates in C-strand fill-in. They also demonstrate that STN1/CST participates in two mechanistically separate steps during telomere replication and identify CST as a novel replication factor that solves diverse replication-associated problems. PMID:23142664

  17. 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

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

    PubMed Central

    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

    2015-01-01

    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

  19. Prevalent flucocorticoid and androgen activity in US water sources

    USGS Publications Warehouse

    Stavreva, Diana A.; George, Anuja A.; Klausmeyer, Paul; Varticovski, Lyuba; Sack, Daniel; Voss, Ty C.; Schiltz, R. Louis; Blazer, Vicki; Iwanowiczl, Luke R.; Hager, Gordon L.

    2012-01-01

    Contamination of the environment with endocrine disrupting chemicals (EDCs) is a major health concern. The presence of estrogenic compounds in water and their deleterious effect are well documented. However, detection and monitoring of other classes of EDCs is limited. Here we utilize a high-throughput live cell assay based on sub-cellular relocalization of GFP-tagged glucocorticoid and androgen receptors (GFP-GR and GFP-AR), in combination with gene transcription analysis, to screen for glucocorticoid and androgen activity in water samples. We report previously unrecognized glucocorticoid activity in 27%, and androgen activity in 35% of tested water sources from 14 states in the US. Steroids of both classes impact body development, metabolism, and interfere with reproductive, endocrine, and immune systems. This prevalent contamination could negatively affect wildlife and human populations.

  20. Androgen receptor (AR) in cardiovascular diseases.

    PubMed

    Huang, Chiung-Kuei; Lee, Soo Ok; Chang, Eugene; Pang, Haiyan; Chang, Chawnshang

    2016-04-01

    Cardiovascular diseases (CVDs) are still the highest leading cause of death worldwide. Several risk factors have been linked to CVDs, including smoking, diabetes, hyperlipidemia, and gender among others. Sex hormones, especially the androgen and its receptor, androgen receptor (AR), have been linked to many diseases with a clear gender difference. Here, we summarize the effects of androgen/AR on CVDs, including hypertension, stroke, atherosclerosis, abdominal aortic aneurysm (AAA), myocardial hypertrophy, and heart failure, as well as the metabolic syndrome/diabetes and their impacts on CVDs. Androgen/AR signaling exacerbates hypertension, and anti-androgens may suppress hypertension. Androgen/AR signaling plays dual roles in strokes, depending on different kinds of factors; however, generally males have a higher incidence of strokes than females. Androgen and AR differentially modulate atherosclerosis. Androgen deficiency causes elevated lipid accumulation to enhance atherosclerosis; however, targeting AR in selective cells without altering serum androgen levels would suppress atherosclerosis progression. Androgen/AR signaling is crucial in AAA development and progression, and targeting androgen/AR profoundly restricts AAA progression. Men have increased cardiac hypertrophy compared with age-matched women that may be due to androgens. Finally, androgen/AR plays important roles in contributing to obesity and insulin/leptin resistance to increase the metabolic syndrome.

  1. Role of 5α-reductase inhibitors in androgen-stimulated skin disorders.

    PubMed

    Azzouni, Faris; Zeitouni, Nathalie; Mohler, James

    2013-02-01

    5α-reductase (5α-R) isozymes are ubiquitously expressed in human tissues. This enzyme family is composed of 3 members that perform several important biologic functions. 5α-R isozymes play an important role in benign prostate hyperplasia, prostate cancer, and androgen-stimulated skin disorders, which include androgenic alopecia, acne, and hirsutism. Discovery of 5α-R type 2 deficiency in 1974 sparked interest in development of pharmaceutical agents to inhibit 5α-R isozymes, and 2 such inhibitors are currently available for clinical use: finasteride and dutasteride. 5α-R inhibitors are US Food and Drug Administration (FDA)-approved for the treatment of benign prostate hyperplasia. Only finasteride is FDA-approved for treatment of male androgenic alopecia. This article reviews the pathophysiology of androgen-stimulated skin disorders and the key clinical trials using 5α-R inhibitors in the treatment of androgen-stimulated skin disorders. PMID:23377402

  2. Anoxic Androgen Degradation by the Denitrifying Bacterium Sterolibacterium denitrificans via the 2,3-seco Pathway

    PubMed Central

    Wang, Po-Hsiang; Yu, Chang-Ping; Lee, Tzong-Huei; Lin, Ching-Wen; Ismail, Wael; Wey, Shiaw-Pyng; Kuo, An-Ti

    2014-01-01

    The biodegradation of steroids is a crucial biochemical process mediated exclusively by bacteria. So far, information concerning the anoxic catabolic pathways of androgens is largely unknown, which has prevented many environmental investigations. In this work, we show that Sterolibacterium denitrificans DSMZ 13999 can anaerobically mineralize testosterone and some C19 androgens. By using a 13C-metabolomics approach and monitoring the sequential appearance of the intermediates, we demonstrated that S. denitrificans uses the 2,3-seco pathway to degrade testosterone under anoxic conditions. Furthermore, based on the identification of a C17 intermediate, we propose that the A-ring cleavage may be followed by the removal of a C2 side chain at C-5 of 17-hydroxy-1-oxo-2,3-seco-androstan-3-oic acid (the A-ring cleavage product) via retro-aldol reaction. The androgenic activities of the bacterial culture and the identified intermediates were assessed using the lacZ-based yeast androgen assay. The androgenic activity in the testosterone-grown S. denitrificans culture decreased significantly over time, indicating its ability to eliminate androgens. The A-ring cleavage intermediate (≤500 μM) did not exhibit androgenic activity, whereas the sterane-containing intermediates did. So far, only two androgen-degrading anaerobes (Sterolibacterium denitrificans DSMZ 13999 [a betaproteobacterium] and Steroidobacter denitrificans DSMZ 18526 [a gammaproteobacterium]) have been isolated and characterized, and both of them use the 2,3-seco pathway to anaerobically degrade androgens. The key intermediate 2,3-seco-androstan-3-oic acid can be used as a signature intermediate for culture-independent environmental investigations of anaerobic degradation of C19 androgens. PMID:24657867

  3. Bypass Mechanisms of the Androgen Receptor Pathway in Therapy-Resistant Prostate Cancer Cell Models

    PubMed Central

    Marques, Rute B.; Dits, Natasja F.; Erkens-Schulze, Sigrun; van Weerden, Wytske M.; Jenster, Guido

    2010-01-01

    Background Prostate cancer is initially dependent on androgens for survival and growth, making hormonal therapy the cornerstone treatment for late-stage tumors. However, despite initial remission, the cancer will inevitably recur. The present study was designed to investigate how androgen-dependent prostate cancer cells eventually survive and resume growth under androgen-deprived and antiandrogen supplemented conditions. As model system, we used the androgen-responsive PC346C cell line and its therapy-resistant sublines: PC346DCC, PC346Flu1 and PC346Flu2. Methodology/Principal Findings Microarray technology was used to analyze differences in gene expression between the androgen-responsive and therapy-resistant PC346 cell lines. Microarray analysis revealed 487 transcripts differentially-expressed between the androgen-responsive and the therapy-resistant cell lines. Most of these genes were common to all three therapy-resistant sublines and only a minority (∼5%) was androgen-regulated. Pathway analysis revealed enrichment in functions involving cellular movement, cell growth and cell death, as well as association with cancer and reproductive system disease. PC346DCC expressed residual levels of androgen receptor (AR) and showed significant down-regulation of androgen-regulated genes (p-value = 10−7). Up-regulation of VAV3 and TWIST1 oncogenes and repression of the DKK3 tumor-suppressor was observed in PC346DCC, suggesting a potential AR bypass mechanism. Subsequent validation of these three genes in patient samples confirmed that expression was deregulated during prostate cancer progression. Conclusions/Significance Therapy-resistant growth may result from adaptations in the AR pathway, but androgen-independence may also be achieved by alternative survival mechanisms. Here we identified TWIST1, VAV3 and DKK3 as potential players in the bypassing of the AR pathway, making them good candidates as biomarkers and novel therapeutical targets. PMID:20976069

  4. Beyond androgen deprivation: ancillary integrative strategies for targeting the androgen receptor addiction of prostate cancer.

    PubMed

    McCarty, Mark F; Hejazi, Jalal; Rastmanesh, Reza

    2014-09-01

    The large majority of clinical prostate cancers remain dependent on androgen receptor (AR) activity for proliferation even as they lose their responsiveness to androgen deprivation or antagonism. AR activity can be maintained in these circumstances by increased AR synthesis--often reflecting increased NF-κB activation; upregulation of signaling pathways that promote AR activity in the absence of androgens; and by emergence of AR mutations or splice variants lacking the ligand-binding domain, which render the AR constitutively active. Drugs targeting the N-terminal transactivating domain of the AR, some of which are now in preclinical development, can be expected to inhibit the activity not only of unmutated ARs but also of the mutant forms and splice variants selected for by androgen deprivation. Concurrent measures that suppress AR synthesis or boost AR turnover could be expected to complement the efficacy of such drugs. A number of nutraceuticals that show efficacy in prostate cancer xenograft models--including polyphenols from pomegranate, grape seed, and green tea, the crucifera metabolite diindolylmethane, and the hormone melatonin--have the potential to suppress AR synthesis via downregulation of NF-κB activity; clinical doses of salicylate may have analogous efficacy. The proteasomal turnover of the AR is abetted by diets with a high ratio of long-chain omega-3 to omega-6 fatty acids, which are beneficial in prostate cancer xenograft models; berberine and sulforaphane, by inhibiting AR's interaction with its chaperone Hsp90, likewise promote AR proteasomal degradation and retard growth of human prostate cancer in nude mice. Hinge region acetylation of the AR is required for optimal transactivational activity, and low micromolar concentrations of the catechin epigallocatechin-3-gallate (EGCG) can inhibit such acetylation--possibly explaining the ability of EGCG administration to suppress androgenic activity and cell proliferation in prostate cancer

  5. Anti-androgens in gynaecological practice.

    PubMed

    Reed, M J; Franks, S

    1988-09-01

    Hirsutism and acne in women are common distressing problems. Unwanted hair growth, acne and seborrhoea result from the action of androgens on the skin. Such effects depend not only on increased androgen production by the ovary or adrenal gland but also on the bioavailability of androgen to peripheral tissues. This in turn is related to transport of androgens in plasma by specific binding proteins and to peripheral metabolism of testosterone and androstenedione to their more potent 5 alpha-reduced derivatives. An effective anti-androgen is one which blocks the androgen receptor-mediated actions of testosterone and DHT on skin. CPA, the treatment of choice in the UK, is a potent androgen receptor-blocking steroid which also has progestational properties. When combined with ethinyloestradiol it also suppresses ovarian function, thus reducing androgen production, and provides effective contraception. PMID:2976627

  6. Hypochlorite Oxidation of Select Androgenic Steroids

    EPA Science Inventory

    Steroid hormones are vital for regulation of various biological functions including sexual development. Elevated concentrations of natural and synthetic androgenic steroids have been shown to adversely affect normal development in indigenous aqueous species. Androgens and their s...

  7. Conformations of Human Telomeric G-Quadruplex Studied Using a Nucleotide-Independent Nitroxide Label.

    PubMed

    Zhang, Xiaojun; Xu, Cui-Xia; Di Felice, Rosa; Sponer, Jiri; Islam, Barira; Stadlbauer, Petr; Ding, Yuan; Mao, Lingling; Mao, Zong-Wan; Qin, Peter Z

    2016-01-19

    Guanine-rich oligonucleotides can form a unique G-quadruplex (GQ) structure with stacking units of four guanine bases organized in a plane through Hoogsteen bonding. GQ structures have been detected in vivo and shown to exert their roles in maintaining genome integrity and regulating gene expression. Understanding GQ conformation is important for understanding its inherent biological role and for devising strategies to control and manipulate functions based on targeting GQ. Although a number of biophysical methods have been used to investigate structure and dynamics of GQs, our understanding is far from complete. As such, this work explores the use of the site-directed spin labeling technique, complemented by molecular dynamics simulations, for investigating GQ conformations. A nucleotide-independent nitroxide label (R5), which has been previously applied for probing conformations of noncoding RNA and DNA duplexes, is attached to multiple sites in a 22-nucleotide DNA strand derived from the human telomeric sequence (hTel-22) that is known to form GQ. The R5 labels are shown to minimally impact GQ folding, and inter-R5 distances measured using double electron-electron resonance spectroscopy are shown to adequately distinguish the different topological conformations of hTel-22 and report variations in their occupancies in response to changes of the environment variables such as salt, crowding agent, and small molecule ligand. The work demonstrates that the R5 label is able to probe GQ conformation and establishes the base for using R5 to study more complex sequences, such as those that may potentially form multimeric GQs in long telomeric repeats. PMID:26678746

  8. Voriconazole Enhances the Osteogenic Activity of Human Osteoblasts In Vitro through a Fluoride-Independent Mechanism

    PubMed Central

    Allen, Kahtonna C.; Sanchez, Carlos J.; Niece, Krista L.; Wenke, Joseph C.

    2015-01-01

    Periostitis, which is characterized by bony pain and diffuse periosteal ossification, has been increasingly reported with prolonged clinical use of voriconazole. While resolution of clinical symptoms following discontinuation of therapy suggests a causative role for voriconazole, the biological mechanisms contributing to voriconazole-induced periostitis are unknown. To elucidate potential mechanisms, we exposed human osteoblasts in vitro to voriconazole or fluconazole at 15 or 200 μg/ml (reflecting systemic or local administration, respectively), under nonosteogenic or osteogenic conditions, for 1, 3, or 7 days and evaluated the effects on cell proliferation (reflected by total cellular DNA) and osteogenic differentiation (reflected by alkaline phosphatase activity, calcium accumulation, and expression of genes involved in osteogenic differentiation). Release of free fluoride, vascular endothelial growth factor (VEGF), and platelet-derived growth factor (PDGF) was also measured in cell supernatants of osteoblasts exposed to triazoles, with an ion-selective electrode (for free fluoride) and enzyme-linked immunosorbent assays (ELISAs) (for VEGF and PDGF). Voriconazole but not fluconazole significantly enhanced the proliferation and differentiation of osteoblasts. In contrast to clinical observations, no increases in free fluoride levels were detected following exposure to either voriconazole or fluconazole; however, significant increases in the expression of VEGF and PDGF by osteoblasts were observed following exposure to voriconazole. Our results demonstrate that voriconazole can induce osteoblast proliferation and enhance osteogenic activity in vitro. Importantly, and in contrast to the previously proposed mechanism of fluoride-stimulated osteogenesis, our findings suggest that voriconazole-induced periostitis may also occur through fluoride-independent mechanisms that enhance the expression of cytokines that can augment osteoblastic activity. PMID:26324277

  9. Interlaboratory comparison of four in vitro assays for assessing androgenic and antiandrogenic activity of environmental chemicals.

    PubMed Central

    Körner, Wolfgang; Vinggaard, Anne Marie; Térouanne, Béatrice; Ma, Risheng; Wieloch, Carise; Schlumpf, Margret; Sultan, Charles; Soto, Ana M

    2004-01-01

    We evaluated and compared four in vitro assays to detect androgen agonists and antagonists in an international interlaboratory study. Laboratory 1 used a cell proliferation assay (assay 1) with human mammary carcinoma cells stably transfected with human androgen receptor. The other laboratories used reporter gene assays, two based on stably transfected human prostate carcinoma cells (assay 2) or human mammary carcinoma cells (assay 4), and the third based on transient transfection of Chinese hamster ovary cells (assay 3). Four laboratories received four coded compounds and two controls: two steroidal androgens, two antiandrogens, an androgenic control, 5alpha-dihydrotestosterone (DHT), and an antiandrogenic control, bicalutamide (ICI 176,334). All laboratories correctly detected the androgenic activity of 4-androsten-3,17-dione and 17alpha-methyltestosterone. For both compounds, the calculated androgenic potencies relative to the positive control (RAPs) remained within one order of magnitude. However, laboratory 3 calculated a 50-fold higher RAP for 4-androsten-3,17-dione. All assays detected and quantified the antiandrogenic effect of vinclozolin [median inhibitory concentration (IC50) values ranging from 1.1 times symbol 10(-7) M to 4.7 times symbol 10(-7) M]. In assays 2 and 3, vinclozolin showed partial androgenic activity at the highest concentrations tested. For vinclozolin, calculated antiandrogenic potencies relative to bicalutamide (RAAPs) differed no more than a factor of 10, and IC50 values matched those of bicalutamide. Similarly, we found antiandrogenic activity for tris-(4-chlorophenyl)methanol. RAAP values were between 0.086 and 0.37. Three assays showed cytotoxicity for this compound at or above 1 times symbol 10(-5) M. In summary, all assays proved sensitive screening tools to detect and quantify androgen receptor-mediated androgenic and antiandrogenic effects of these chemicals accurately, with coefficients of variation between 8 and 90%. PMID

  10. Role of the HSP90-associated cochaperone p23 in enhancing activity of the androgen receptor and significance for prostate cancer.

    PubMed

    Reebye, Vikash; Querol Cano, Laia; Lavery, Derek N; Brooke, Greg N; Powell, Sue M; Chotai, Deepa; Walker, Marjorie M; Whitaker, Hayley C; Wait, Robin; Hurst, Helen C; Bevan, Charlotte L

    2012-10-01

    Prostate tumor growth initially depends on androgens, which act via the androgen receptor (AR). Despite androgen ablation therapy, tumors eventually progress to a castrate-resistant stage in which the AR remains active. The mechanisms are poorly understood but it may be that changes in levels or activity of AR coregulators affect trafficking and activation of the receptor. A key stage in AR signaling occurs in the cytoplasm, where unliganded receptor is associated with the heat shock protein (HSP)90 foldosome complex. p23, a key component of this complex, is best characterized as a cochaperone for HSP90 but also has HSP90-independent activity and has been reported as having differential effects on the activity of different steroid receptors. Here we report that p23 increases activity of the AR, and this appears to involve steps both in the cytoplasm (increasing ligand-binding capacity, possibly via direct interaction with AR) and the nucleus (enhancing AR occupancy at target promoters). We show, for the first time, that AR and p23 can interact, perhaps directly, when HSP90 is not present in the same complex. The effects of p23 on AR activity are at least partly HSP90 independent because a mutant form of p23, unable to bind HSP90, nevertheless increases AR activity. In human prostate tumors, nuclear p23 was higher in malignant prostate cells compared with benign/normal cells, supporting the utility of p23 as a therapeutic target in prostate cancer.

  11. 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

  12. The primate thyroid gland contains receptors for androgens.

    PubMed

    Sheridan, P J; McGill, H C; Lissitzky, J C; Martin, P M

    1984-12-01

    The gonadal steroids have long been known to modulate thyroid function. Most studies suggest that the gonadal steroids act indirectly through the hypothalamic-pituitary axis to modulate thyroid function. The following studies were conducted to determine whether there are receptors for androgens in the thyroid itself. Cytosols from male and female euthyroid patients were analyzed for the presence of androgen with the synthetic analog methyltrienolone [( 3H]R1881). No evidence of androgen receptors was found in any of the cytosols prepared from female patients. In all males studied, androgen receptors were found in concentrations ranging from 100-150 fmol/10 mg DNA for the cytosols and from 690-2800 fmol/10 mg DNA for the nuclear extracts. The receptors had a dissociation constant (Kd) of approximately 5-10 X 10(-10) M for the cytosol and approximately 10-15 X 10(-10) M for the nuclear extracts. In addition to the human studies, studies in baboons were conducted to determine the possible cell type which might contain receptors for androgens. Male and female baboons were injected with [3H] dihydrotestosterone and killed between 1 and 1 1/2 h later. The thyroids were removed and processed for autoradiography. In autoradiograms from animals injected with [3H]dihydrotestosterone, nuclear localization of radioactivity was found in virtually all of the follicular cells. Also, label was found overlying the colloid, with heaviest labeling near the cells. These data suggest that there may be direct actions of androgens on follicular cells.

  13. 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

  14. 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

  15. The role of androgens in follicle maturation and ovulation induction: friend or foe of infertility treatment?

    PubMed Central

    2011-01-01

    Background Effects of androgens on follicle maturation have been controversial for some time. Here, we review the potential of their applications in improving human ovulation induction, based on human and animal data, reported in the literature. Methods We reviewed the published literature for the years 2005-2011, using relevant key words, in PubMed, Medline and Cochrane reviews, and then performed secondary reviews of referenced articles, which previously had not been known or preceded the searched time period. A total of 217 publications were reviewed. Results Contrary to widely held opinion, recent data, mostly developed in the mouse, convincingly demonstrate essential contribution of androgens to normal follicle maturation and, therefore, female fertility. Androgens appear most engaged at preantral and antral stages, primarily affect granulosa cells, and exert effects via androgen receptors (AR) through transcriptional regulation but also in non-genomic ways, with ligand-activated AR modulating follicle stimulating hormone (FSH) activity in granulosa cells. While some androgens, like testosterone (T) and dehydroepiandrosterone (DHEA), appear effective in improving functional ovarian reserve (FOR) in women with diminished ovarian reserve (DOR), others may even exert opposite effects. Such differences in androgens may, at least partially, reflect different levels of agonism to AR. Discussion Selective androgens appear capable of improving early stages of folliculogenesis. They, therefore, may represent forerunners of a completely new class of ovulation-inducing medications, which, in contrast to gonadotropins, affect follicle maturation at much earlier stages. PMID:21849061

  16. Geranylated 4-Phenylcoumarins Exhibit Anticancer Effects against Human Prostate Cancer Cells through Caspase-Independent Mechanism

    PubMed Central

    Suparji, Noor Shahirah; Chan, Gomathi; Sapili, Hani; Arshad, Norhafiza M.; In, Lionel L. A.; Awang, Khalijah; Hasima Nagoor, Noor

    2016-01-01

    Geranylated 4-phenylcoumarins, DMDP-1 & -2 isolated from Mesua elegans were investigated for anticancer potential against human prostate cancer cells. Treatment with DMDP-1 & -2 resulted in cell death in a time and dose dependent manner in an MTT assay on all cancer cell lines tested with the exception of lung adenocarcinoma cells. DMDP-1 showed highest cytotoxic efficacy in PC-3 cells while DMDP-2 was most potent in DU 145 cells. Flow cytometry indicated that both coumarins were successful to induce programmed cell death after 24 h treatment. Elucidation on the mode-of-action via protein arrays and western blotting demonstrated death induced without any significant expressions of caspases, Bcl-2 family proteins and cleaved PARP, thus suggesting the involvement of caspase-independent pathways. In identifying autophagy, analysis of GFP-LC3 showed increased punctate in PC-3 cells pre-treated with CQ and treated with DMDP-1. In these cells decreased expression of autophagosome protein, p62 and cathepsin B further confirmed autophagy. In contrary, the DU 145 cells pre-treated with CQ and treated with DMDP-2 has reduced GFP-LC3 punctate although the number of cells with obvious GFP-LC3 puncta was significantly increased in the inhibitor-treated cells. The increase level of p62 suggested leakage of cathepsin B into the cytosol to trigger potential downstream death mediators. This correlated with increased expression of cathepsin B and reduced expression after treatment with its inhibitor, CA074. Also auto-degradation of calpain-2 upon treatment with DMDP-1 &-2 and its inhibitor alone, calpeptin compared with the combination treatment, further confirmed involvement of calpain-2 in PC-3 and DU 145 cells. Treatment with DMDP-1 & -2 also showed up-regulation of total and phosphorylated p53 levels in a time dependent manner. Hence, DMDP-1 & -2 showed ability to activate multiple death pathways involving autophagy, lysosomal and endoplasmic reticulum death proteins which could

  17. Clarifying CB2 receptor-dependent and independent effects of THC on human lung epithelial cells

    SciTech Connect

    Sarafian, Theodore Montes, Cindy; Harui, Airi; Beedanagari, Sudheer R.; Kiertscher, Sylvia; Stripecke, Renata; Hossepian, Derik; Kitchen, Christina; Kern, Rita; Belperio, John; Roth, Michael D.

    2008-09-15

    Marijuana smoking is associated with a number of abnormal findings in the lungs of habitual smokers. Previous studies revealed that {delta}{sup 9}-tetrahydrocannabinol (THC) caused mitochondrial injury in primary lung epithelial cells and in the cell line, A549 [Sarafian, T. A., Kouyoumjian, S., Khoshaghideh, F., Tashkin, D. P., and Roth, M. D. (2003). Delta 9-tetrahydrocannabinol disrupts mitochondrial function and cell energetics. Am J Physiol Lung Cell Mol Physiol 284, L298-306; Sarafian, T., Habib, N., Mao, J. T., Tsu, I. H., Yamamoto, M. L., Hsu, E., Tashkin, D. P., and Roth, M. D. (2005). Gene expression changes in human small airway epithelial cells exposed to Delta9-tetrahydrocannabinol. Toxicol Lett 158, 95-107]. The role of cannabinoid receptors in this injury was unclear, as was the potential impact on cell function. In order to investigate these questions, A549 cells were engineered to over-express the type 2 cannabinoid receptor (CB2R) using a self-inactivating lentiviral vector. This transduction resulted in a 60-fold increase in CB2R mRNA relative to cells transduced with a control vector. Transduced cell lines were used to study the effects of THC on chemotactic activity and mitochondrial function. Chemotaxis in response to a 10% serum gradient was suppressed in a concentration-dependent manner by exposure to THC. CB2R-transduced cells exhibited less intrinsic chemotactic activity (p < 0.05) and were 80- to 100-fold more sensitive to the inhibitory effects of THC. Studies using SR144528, a selective CB2R antagonist, verified that these effects were mediated by the CB2R. Marijuana smoke extract, but not smoke extracts from tobacco or placebo marijuana cigarettes, reproduced these effects (p < 0.05). THC decreased ATP level and mitochondrial membrane potential ({psi}{sub m}) in both control and CB2R-transduced cells. However, these decreases did not play a significant role in chemotaxis inhibition since cyclosporine A, which protected against ATP loss

  18. Non-Cell-Autonomous Regulation of Prostate Epithelial Homeostasis by Androgen Receptor.

    PubMed

    Zhang, Boyu; Kwon, Oh-Joon; Henry, Gervaise; Malewska, Alicia; Wei, Xing; Zhang, Li; Brinkley, William; Zhang, Yiqun; Castro, Patricia D; Titus, Mark; Chen, Rui; Sayeeduddin, Mohammad; Raj, Ganesh V; Mauck, Ryan; Roehrborn, Claus; Creighton, Chad J; Strand, Douglas W; Ittmann, Michael M; Xin, Li

    2016-09-15

    Prostate inflammation has been suggested as an etiology for benign prostatic hyperplasia (BPH). We show that decreased expression of the androgen receptor (AR) in luminal cells of human BPH specimens correlates with a higher degree of regional prostatic inflammation. However, the cause-and-effect relationship between the two events remains unclear. We investigated specifically whether attenuating AR activity in prostate luminal cells induces inflammation. Disrupting luminal cell AR signaling in mouse models promotes cytokine production cell-autonomously, impairs epithelial barrier function, and induces immune cell infiltration, which further augments local production of cytokines and chemokines including Il-1 and Ccl2. This inflammatory microenvironment promotes AR-independent prostatic epithelial proliferation, which can be abolished by ablating IL-1 signaling or depleting its major cellular source, the macrophages. This study demonstrates that disrupting luminal AR signaling promotes prostate inflammation, which may serve as a mechanism for resistance to androgen-targeted therapy for prostate-related diseases. PMID:27594448

  19. Targeting intratumoral androgens: statins and beyond.

    PubMed

    Schweizer, Michael T; Yu, Evan Y

    2016-09-01

    While initially effective, androgen deprivation therapy (ADT) is not curative, and nearly all men with advanced prostate cancer will eventually progress to the more resistant, and ultimately lethal form of the disease, so called castration-resistant prostate cancer (CRPC). The maintenance of androgens within the prostate cancer microenvironment likely represents one of the key mechanisms by which this transition from hormone-sensitive to CRPC occurs. This can be accomplished either through intratumoral androgen biosynthesis or the active transport of androgens and androgenic precursors into the tumor microenvironment. More recently, preclinical and clinical data supported therapeutic strategies that seek to target these two mechanisms, either through the use of drugs that impair androgen biosynthesis (e.g. inhibiting the steroidogenic enzymes CYP17 and AKR1C3 with abiraterone and indomethacin, respectively) or drugs that inhibit the SLCO transporters responsible for importing androgens (e.g. statins). PMID:27583031

  20. Targeting intratumoral androgens: statins and beyond

    PubMed Central

    Schweizer, Michael T.; Yu, Evan Y.

    2016-01-01

    While initially effective, androgen deprivation therapy (ADT) is not curative, and nearly all men with advanced prostate cancer will eventually progress to the more resistant, and ultimately lethal form of the disease, so called castration-resistant prostate cancer (CRPC). The maintenance of androgens within the prostate cancer microenvironment likely represents one of the key mechanisms by which this transition from hormone-sensitive to CRPC occurs. This can be accomplished either through intratumoral androgen biosynthesis or the active transport of androgens and androgenic precursors into the tumor microenvironment. More recently, preclinical and clinical data supported therapeutic strategies that seek to target these two mechanisms, either through the use of drugs that impair androgen biosynthesis (e.g. inhibiting the steroidogenic enzymes CYP17 and AKR1C3 with abiraterone and indomethacin, respectively) or drugs that inhibit the SLCO transporters responsible for importing androgens (e.g. statins). PMID:27583031

  1. Yolk androgens reduce offspring survival.

    PubMed

    Sockman, K W; Schwabl, H

    2000-07-22

    Females may favour some offspring over others by differential deposition of yolk hormones. In American kestrels (Falco sparverius), we found that yolks of eggs laid late in the sequence of a clutch had more testosterone (T) and androstenedione (A4) than yolks of first-laid eggs. To investigate the effects of these yolk androgens on nestling 'fitness', we injected both T and A4 into the yolks of first-laid eggs and compared their hatching time, nestling growth and nestling survival with those of first-laid eggs in which we injected vehicle as a control. Compared to controls, injection of T and A4 at a dose intended to increase their levels to those of later-laid eggs delayed hatching and reduced nestling growth and survival rates. Yolk androgen treatment of egg 1 had no effect on survival of siblings hatching from subsequently laid eggs. The adverse actions of yolk androgen treatment in the kestrel are in contrast to the favourable actions of yolk T treatment found previously in canaries (Serinus canaria). Additional studies are necessary in order to determine whether the deposition of yolk androgens is an adaptive form of parental favouritism or an adverse by-product of endocrine processes during egg formation. Despite its adaptive significance, such 'transgenerational' effects of steroid hormones may have helped to evolutionarily shape the hormonal mechanisms regulating reproduction. PMID:10983830

  2. Yolk androgens reduce offspring survival.

    PubMed Central

    Sockman, K W; Schwabl, H

    2000-01-01

    Females may favour some offspring over others by differential deposition of yolk hormones. In American kestrels (Falco sparverius), we found that yolks of eggs laid late in the sequence of a clutch had more testosterone (T) and androstenedione (A4) than yolks of first-laid eggs. To investigate the effects of these yolk androgens on nestling 'fitness', we injected both T and A4 into the yolks of first-laid eggs and compared their hatching time, nestling growth and nestling survival with those of first-laid eggs in which we injected vehicle as a control. Compared to controls, injection of T and A4 at a dose intended to increase their levels to those of later-laid eggs delayed hatching and reduced nestling growth and survival rates. Yolk androgen treatment of egg 1 had no effect on survival of siblings hatching from subsequently laid eggs. The adverse actions of yolk androgen treatment in the kestrel are in contrast to the favourable actions of yolk T treatment found previously in canaries (Serinus canaria). Additional studies are necessary in order to determine whether the deposition of yolk androgens is an adaptive form of parental favouritism or an adverse by-product of endocrine processes during egg formation. Despite its adaptive significance, such 'transgenerational' effects of steroid hormones may have helped to evolutionarily shape the hormonal mechanisms regulating reproduction. PMID:10983830

  3. Stress and Androgen Activity During Fetal Development.

    PubMed

    Barrett, Emily S; Swan, Shanna H

    2015-10-01

    Prenatal stress is known to alter hypothalamic-pituitary-adrenal axis activity, and more recent evidence suggests that it may also affect androgen activity. In animal models, prenatal stress disrupts the normal surge of testosterone in the developing male, whereas in females, associations differ by species. In humans, studies show that (1) associations between prenatal stress and child outcomes are often sex-dependent, (2) prenatal stress predicts several disorders with notable sex differences in prevalence, and (3) prenatal exposure to stressful life events may be associated with masculinized reproductive tract development and play behavior in girls. In this minireview, we examine the existing literature on prenatal stress and androgenic activity and present new, preliminary data indicating that prenatal stress may also modify associations between prenatal exposure to diethylhexyl phthalate, (a synthetic, antiandrogenic chemical) and reproductive development in infant boys. Taken together, these data support the hypothesis that prenatal exposure to both chemical and nonchemical stressors may alter sex steroid pathways in the maternal-placental-fetal unit and ultimately alter hormone-dependent developmental endpoints. PMID:26241065

  4. Stress and Androgen Activity During Fetal Development

    PubMed Central

    Swan, Shanna H.

    2015-01-01

    Prenatal stress is known to alter hypothalamic-pituitary-adrenal axis activity, and more recent evidence suggests that it may also affect androgen activity. In animal models, prenatal stress disrupts the normal surge of testosterone in the developing male, whereas in females, associations differ by species. In humans, studies show that (1) associations between prenatal stress and child outcomes are often sex-dependent, (2) prenatal stress predicts several disorders with notable sex differences in prevalence, and (3) prenatal exposure to stressful life events may be associated with masculinized reproductive tract development and play behavior in girls. In this minireview, we examine the existing literature on prenatal stress and androgenic activity and present new, preliminary data indicating that prenatal stress may also modify associations between prenatal exposure to diethylhexyl phthalate, (a synthetic, antiandrogenic chemical) and reproductive development in infant boys. Taken together, these data support the hypothesis that prenatal exposure to both chemical and nonchemical stressors may alter sex steroid pathways in the maternal-placental-fetal unit and ultimately alter hormone-dependent developmental endpoints. PMID:26241065

  5. De novo der(X)t(X;10)(q26;q21) with features of distal trisomy 10q: case report of paternal origin identified by late replication with BrdU and the human androgen receptor assay (HAR).

    PubMed Central

    Garcia-Heras, J; Martin, J A; Witchel, S F; Scacheri, P

    1997-01-01

    We describe an 11 year old girl with a de novo unbalanced t(X;10) that resulted in a deletion of Xq26-->Xqter and a trisomy of 10q21-->10qter. Her clinical features were of distal trisomy 10q, but she lacked the cardiovascular and renal malformations observed in duplications of 10q24-->10qter and had only moderate mental retardation. X inactivation was assessed on peripheral blood lymphocytes by late replication with BrdU (LR) and the human androgen receptor assay (HAR). By LR the der(X) was inactive without spreading to 10q21-->10qter in all cells. The HAR assay showed skewed methylation of the paternal allele (90%). The correlation of HAR and LR suggests that the der(X) was paternally inherited and is consistent with data from other de novo balanced and unbalanced X;autosome translocations detected in females. This is the first report of parental origin of a de novo trisomy 10q. Images PMID:9132498

  6. Immunohistochemical Evaluation of Androgen Receptor and Nerve Structure Density in Human Prepuce from Patients with Persistent Sexual Side Effects after Finasteride Use for Androgenetic Alopecia

    PubMed Central

    Di Loreto, Carla; La Marra, Francesco; Mazzon, Giorgio; Belgrano, Emanuele; Trombetta, Carlo; Cauci, Sabina

    2014-01-01

    Finasteride is an inhibitor of 5-α-reductase used against male androgenetic alopecia (AGA). Reported side effects of finasteride comprise sexual dysfunction including erectile dysfunction, male infertility, and loss of libido. Recently these effects were described as persistent in some subjects. Molecular events inducing persistent adverse sexual symptoms are unexplored. This study was designed as a retrospective case-control study to assess if androgen receptor (AR) and nerve density in foreskin prepuce specimens were associated with persistent sexual side effects including loss of sensitivity in the genital area due to former finasteride use against AGA. Cases were 8 males (aged 29–43 years) reporting sexual side effects including loss of penis sensitivity over 6 months after discontinuation of finasteride who were interviewed and clinically visited. After informed consent they were invited to undergo a small excision of skin from prepuce. Controls were 11 otherwise healthy matched men (aged 23–49 years) who undergone circumcision for phimosis, and who never took finasteride or analogues. Differences in AR expression and nerve density in different portions of dermal prepuce were evaluated in the 2 groups. Density of nuclear AR in stromal and epithelial cells was higher in cases (mean 40.0%, and 80.6% of positive cells, respectively) than controls (mean 23.4%, and 65.0% of positive cells, respectively), P = 0.023 and P = 0.043, respectively. Conversely, percentage of vessel smooth muscle cells positive for AR and density of nerves were similar in the 2 groups. The ratio of AR positive stromal cells % to serum testosterone concentrations was 2-fold higher in cases than in controls (P = 0.001). Our findings revealed that modulation of local AR levels might be implicated in long-term side effects of finasteride use. This provides the first evidence of a molecular objective difference between patients with long-term adverse sexual effects after

  7. Immunohistochemical evaluation of androgen receptor and nerve structure density in human prepuce from patients with persistent sexual side effects after finasteride use for androgenetic alopecia.

    PubMed

    Di Loreto, Carla; La Marra, Francesco; Mazzon, Giorgio; Belgrano, Emanuele; Trombetta, Carlo; Cauci, Sabina

    2014-01-01

    Finasteride is an inhibitor of 5-α-reductase used against male androgenetic alopecia (AGA). Reported side effects of finasteride comprise sexual dysfunction including erectile dysfunction, male infertility, and loss of libido. Recently these effects were described as persistent in some subjects. Molecular events inducing persistent adverse sexual symptoms are unexplored. This study was designed as a retrospective case-control study to assess if androgen receptor (AR) and nerve density in foreskin prepuce specimens were associated with persistent sexual side effects including loss of sensitivity in the genital area due to former finasteride use against AGA. Cases were 8 males (aged 29-43 years) reporting sexual side effects including loss of penis sensitivity over 6 months after discontinuation of finasteride who were interviewed and clinically visited. After informed consent they were invited to undergo a small excision of skin from prepuce. Controls were 11 otherwise healthy matched men (aged 23-49 years) who undergone circumcision for phimosis, and who never took finasteride or analogues. Differences in AR expression and nerve density in different portions of dermal prepuce were evaluated in the 2 groups. Density of nuclear AR in stromal and epithelial cells was higher in cases (mean 40.0%, and 80.6% of positive cells, respectively) than controls (mean 23.4%, and 65.0% of positive cells, respectively), P = 0.023 and P = 0.043, respectively. Conversely, percentage of vessel smooth muscle cells positive for AR and density of nerves were similar in the 2 groups. The ratio of AR positive stromal cells % to serum testosterone concentrations was 2-fold higher in cases than in controls (P = 0.001). Our findings revealed that modulation of local AR levels might be implicated in long-term side effects of finasteride use. This provides the first evidence of a molecular objective difference between patients with long-term adverse sexual effects after

  8. Androgen Levels in Older Men Who Have or Who Are at Risk of Acquiring HIV Infection

    PubMed Central

    Klein, Robert S.; Lo, Yungtai; Santoro, Nanette; Dobs, Adrian S.

    2008-01-01

    Objective To determine the prevalence of, risk factors for, and clinical manifestations of low androgen levels in older men who have or who are at risk of acquiring human immunodeficiency virus (HIV) infection, we performed a cross-sectional analysis of an observational cohort of men aged ≥49 years old. Methods A standardized interview (regarding demographic characteristics, behaviors, and medical history) was performed, and body mass index, HIV serologic data, CD4+ cell count, the presence of hepatitis C virus (HCV) markers, and serum testosterone and human sex-binding hormone levels were determined. Factors associated with androgen levels were assessed using logistic regression models. Results Among 502 men (age, 49−81 years) who were not taking androgens, 54% had total testosterone levels of <300 ng/dL. Low androgen levels were associated with injection drug use, HCV infection, high body mass index, and use of psychotropic medications (P < .05); black race was associated with higher androgen levels. Only among men who reported having sex with men was low testosterone level associated with HIV infection (adjusted odds ratio [ORadj] for total testosterone level of <300 ng/dL, 5.1; 95% confidence interval [CI], 1.2−22.4), but among all HIV-seropositive men, HIV load of >10,000 copies/mL was associated with a testosterone level of <200 ng/dL (ORadj, 2.1; 95% CI, 1.1−4.3; P = .03). On univariate analysis, low androgen levels were associated with decreased interest in sex, depressive symptoms, loss of concentration/memory, difficulty sleeping, osteopenia, and poorer subjective health (P < .05). Conclusions Most older men at risk for HIV infection have low androgen levels. Injection drug use, high body mass index, HCV infection, and use of psychotropic medications are associated with low androgen levels, and low androgen levels are associated with symptoms of hypogonadism. PMID:16288406

  9. Human-resource professionals' perceptions of organizational politics as a function of experience, organizational size, and perceived independence.

    PubMed

    Conner, Deondra S

    2006-12-01

    The author examined human-resource professionals' occupation-related and general work experience, socialization from participation in professional activities, organizational size, and perceived independence as predictors of perceptions of organizational politics (POPS). Results varied with the author's use of the overall POPS scale (K. M. Kacmar & G. R. Ferris, 1991) vs. a more specific subscale that measured perceptions related to such issues as pay- and promotion-related politics. It was most notable that work experience appeared to have an inverse relationship with POPS among human-resource professionals in the area of pay and promotions. The author discussed results in relation to the implications and directions for future research.

  10. Proton-HZE-particle sequential dual-beam exposures increase anchorage-independent growth frequencies in primary human fibroblasts.

    PubMed

    Zhou, Guangming; Bennett, Paula V; Cutter, Noelle C; Sutherland, Betsy M

    2006-09-01

    The radiation field in deep space contains high levels of high-energy protons and substantially lower levels of high-atomic-number, high-energy (HZE) particles. Calculations indicate that cellular nuclei of human space travelers will be hit during a 3-year Mars mission by approximately 400 protons and approximately 0.4 HZE particles. Thus most cells in astronauts will be hit by a proton(s) before being hit by an HZE particle. To investigate effects of dual ion irradiations on human cells, we irradiated primary human neonatal fibroblasts with protons (1 GeV/nucleon, 20 cGy) followed from 2.5 min to 48 h later by iron or titanium ions (1 GeV/nucleon, 20 cGy) and then measured clonogenic survival and frequency of anchorage-independent growth. This frequency depends on the interval between hydrogen- and iron-ion irradiation, with a critical window between 2.5 min and 1 h producing about three times more anchorage-independent colonies per survivor than expected from simple addition of the two ions separately. The hydrogen-titanium-ion dual-beam irradiation produced similar increases that persisted to approximately 6 h. At longer intervals, anchorage-independent growth frequencies were similar to those expected for additivity. However, irradiation of cells with either an iron or a titanium particle first followed by protons produced only additive levels. PMID:16953667

  11. The developmental program of human dendritic cells is operated independently of conventional myeloid and lymphoid pathways

    PubMed Central

    Ishikawa, Fumihiko; Niiro, Hiroaki; Iino, Tadafumi; Yoshida, Shuro; Saito, Noriyuki; Onohara, Shinya; Miyamoto, Toshihiro; Minagawa, Hiroko; Fujii, Shin-ichiro; Shultz, Leonard D.; Harada, Mine

    2007-01-01

    Two distinct dendritic cell (DC) subsets, conventional DCs (cDCs) and plasmacytoid DCs (pDCs), have been shown to develop via either the myeloid or the lymphoid pathway in murine hematopoiesis. Lineage-specific phenotypes or functions of “myeloid” and “lymphoid” DCs, however, still remain elusive. Furthermore, such analysis has been particularly difficult in humans, due to lack of an assay system appropriate for the analysis of human stem and progenitor cell differentiation. Here, using a highly efficient xenotransplantation model, we extensively analyze the origin and the molecular signature of human DCs. Purified human common myeloid progenitors (CMPs) and common lymphoid progenitors (CLPs) were intravenously transplanted into nonobese diabetic–severe combined immunodeficiency (NOD-scid)/IL2rγnull newborn mice. CMPs and CLPs displayed significant expansion in the xenogeneic host, and human cDC and pDC progeny were isolatable. Strikingly, each human DC subset possessed indistinguishable expression patterns of surface phenotype and gene transcripts regardless of their CMP or CLP origin, even at the genome-wide level. Thus, cDC and pDC normally develop after cells have committed to the myeloid or the lymphoid lineage in human hematopoiesis, while their transcriptional signatures are well preserved irrespective of their lineage origin. We propose that human DCs use unique and flexible developmental programs that cannot be categorized into the conventional myeloid or lymphoid pathway. PMID:17664352

  12. Pumpkin seed extract: Cell growth inhibition of hyperplastic and cancer cells, independent of steroid hormone receptors.

    PubMed

    Medjakovic, Svjetlana; Hobiger, Stefanie; Ardjomand-Woelkart, Karin; Bucar, Franz; Jungbauer, Alois

    2016-04-01

    Pumpkin seeds have been known in folk medicine as remedy for kidney, bladder and prostate disorders since centuries. Nevertheless, pumpkin research provides insufficient data to back up traditional beliefs of ethnomedical practice. The bioactivity of a hydro-ethanolic extract of pumpkin seeds from the Styrian pumpkin, Cucurbita pepo L. subsp. pepo var. styriaca, was investigated. As pumpkin seed extracts are standardized to cucurbitin, this compound was also tested. Transactivational activity was evaluated for human androgen receptor, estrogen receptor and progesterone receptor with in vitro yeast assays. Cell viability tests with prostate cancer cells, breast cancer cells, colorectal adenocarcinoma cells and a hyperplastic cell line from benign prostate hyperplasia tissue were performed. As model for non-hyperplastic cells, effects on cell viability were tested with a human dermal fibroblast cell line (HDF-5). No transactivational activity was found for human androgen receptor, estrogen receptor and progesterone receptor, for both, extract and cucurbitin. A cell growth inhibition of ~40-50% was observed for all cell lines, with the exception of HDF-5, which showed with ~20% much lower cell growth inhibition. Given the receptor status of some cell lines, a steroid-hormone receptor independent growth inhibiting effect can be assumed. The cell growth inhibition for fast growing cells together with the cell growth inhibition of prostate-, breast- and colon cancer cells corroborates the ethnomedical use of pumpkin seeds for a treatment of benign prostate hyperplasia. Moreover, due to the lack of androgenic activity, pumpkin seed applications can be regarded as safe for the prostate.

  13. Human IgG1 antibodies suppress angiogenesis in a target-independent manner

    PubMed Central

    Bogdanovich, Sasha; Kim, Younghee; Mizutani, Takeshi; Yasuma, Reo; Tudisco, Laura; Cicatiello, Valeria; Bastos-Carvalho, Ana; Kerur, Nagaraj; Hirano, Yoshio; Baffi, Judit Z; Tarallo, Valeria; Li, Shengjian; Yasuma, Tetsuhiro; Arpitha, Parthasarathy; Fowler, Benjamin J; Wright, Charles B; Apicella, Ivana; Greco, Adelaide; Brunetti, Arturo; Ruvo, Menotti; Sandomenico, Annamaria; Nozaki, Miho; Ijima, Ryo; Kaneko, Hiroki; Ogura, Yuichiro; Terasaki, Hiroko; Ambati, Balamurali K; Leusen, Jeanette HW; Langdon, Wallace Y; Clark, Michael R; Armour, Kathryn L; Bruhns, Pierre; Verbeek, J Sjef; Gelfand, Bradley D; De Falco, Sandro; Ambati, Jayakrishna

    2016-01-01

    Aberrant angiogenesis is implicated in diseases affecting nearly 10% of the world’s population. The most widely used anti-angiogenic drug is bevacizumab, a humanized IgG1 monoclonal antibody that targets human VEGFA. Although bevacizumab does not recognize mouse Vegfa, it inhibits angiogenesis in mice. Here we show bevacizumab suppressed angiogenesis in three mouse models not via Vegfa blockade but rather Fc-mediated signaling through FcγRI (CD64) and c-Cbl, impairing macrophage migration. Other approved humanized or human IgG1 antibodies without mouse targets (adalimumab, alemtuzumab, ofatumumab, omalizumab, palivizumab and tocilizumab), mouse IgG2a, and overexpression of human IgG1-Fc or mouse IgG2a-Fc, also inhibited angiogenesis in wild-type and FcγR humanized mice. This anti-angiogenic effect was abolished by Fcgr1 ablation or knockdown, Fc cleavage, IgG-Fc inhibition, disruption of Fc-FcγR interaction, or elimination of FcRγ-initated signaling. Furthermore, bevacizumab’s Fc region potentiated its anti-angiogenic activity in humanized VEGFA mice. Finally, mice deficient in FcγRI exhibited increased developmental and pathological angiogenesis. These findings reveal an unexpected anti-angiogenic function for FcγRI and a potentially concerning off-target effect of hIgG1 therapies. PMID:26918197

  14. Sphingosine kinase-1 mediates androgen-induced osteoblast cell growth

    SciTech Connect

    Martin, Claire; Lafosse, Jean-Michel; Malavaud, Bernard; Cuvillier, Olivier

    2010-01-01

    Herein we report that the lipid kinase sphingosine kinase-1 (SphK1) is instrumental in mediating androgen-induced cell proliferation in osteoblasts. Dihydrotestosterone (DHT) triggered cell growth in steroid-deprived MC3T3 cells, which was associated with a rapid stimulation of SphK1 and activation of both Akt and ERK signaling pathways. This mechanism relied on functional androgen receptor/PI3K/Akt nongenotropic signaling as pharmacological antagonists could block SphK1 stimulation by DHT and its consequences. Finally, SphK1 inhibition not only abrogated DHT-induced ERK activation but also blocked cell proliferation, while ERK inhibition had no impact, suggesting that SphK1 was critical for DHT signaling yet independently of the ERK.

  15. LncRNA HOTAIR Enhances the Androgen-Receptor-Mediated Transcriptional Program and Drives Castration-Resistant Prostate Cancer.

    PubMed

    Zhang, Ali; Zhao, Jonathan C; Kim, Jung; Fong, Ka-Wing; Yang, Yeqing Angela; Chakravarti, Debabrata; Mo, Yin-Yuan; Yu, Jindan

    2015-10-01

    Understanding the mechanisms of androgen receptor (AR) activation in the milieu of low androgen is critical to effective treatment of castration-resistant prostate cancer (CRPC). Here, we report HOTAIR as an androgen-repressed lncRNA, and, as such, it is markedly upregulated following androgen deprivation therapies and in CRPC. We further demonstrate a distinct mode of lncRNA-mediated gene regulation, wherein HOTAIR binds to the AR protein to block its interaction with the E3 ubiquitin ligase MDM2, thereby preventing AR ubiquitination and protein degradation. Consequently, HOTAIR expression is sufficient to induce androgen-independent AR activation and drive the AR-mediated transcriptional program in the absence of androgen. Functionally, HOTAIR overexpression increases, whereas HOTAIR knockdown decreases, prostate cancer cell growth and invasion. Taken together, our results provide compelling evidence of lncRNAs as drivers of androgen-independent AR activity and CRPC progression, and they support the potential of lncRNAs as therapeutic targets.

  16. Neuroprotective actions of androgens on motoneurons.

    PubMed

    Fargo, Keith N; Foecking, Eileen M; Jones, Kathryn J; Sengelaub, Dale R

    2009-07-01

    Androgens have a variety of protective and therapeutic effects in both the central and peripheral nervous systems. Here we review these effects as they related specifically to spinal and cranial motoneurons. Early in development, androgens are critical for the formation of important neuromuscular sex differences, decreasing the magnitude of normally occurring cell death in select motoneuron populations. Throughout the lifespan, androgens also protect against motoneuron death caused by axonal injury. Surviving motoneurons also display regressive changes to their neurites as a result of both direct axonal injury and loss of neighboring motoneurons. Androgen treatment enhances the ability of motoneurons to recover from these regressive changes and regenerate both axons and dendrites, restoring normal neuromuscular function. Androgens exert these protective effects by acting through a variety of molecular pathways. Recent work has begun to examine how androgen treatment can interact with other treatment strategies in promoting recovery from motoneuron injury.

  17. [How independent pharmacological screenings in plants and humans led to the discovery of a new family of lipid metabolism inhibitors].

    PubMed

    Chevalier, Florian; Maréchal, Éric

    2015-03-01

    In eukaryotic cells, phosphatidic acid (PA) and diacylglycerol (DAG), are at the origin of all membrane glycerolipids. Their interconversion is achieved by dephosphorylation of PA and phosphorylation of DAG: they form therefore a metabolic hub. PA and DAG are also known to be versatile signaling molecules. Two independent pharmacological screenings conducted on plant and human targets, led to the discovery of a new family of compounds acting on enzymes binding to either PA or DAG, in biological contexts that seemed initially independent. On the one hand, in plants, monogalactosyldiacylglycerol synthases (MGDG synthases or MGD) are responsible for the synthesis of MGDG, which is the most profuse lipid of photosynthetic membranes, and thus essential for metabolism and development. MGD use DAG as substrate. On the other hand, in mammals, phospholipases D (PLD), that produce PA, are involved in a variety of signaling cascades that control a broad spectrum of cellular functions, and play a role in the development of cancers. The two independent pharmacological screenings described in this review aimed to identify inhibitory molecules of either MGD of the plant model Arabidopsis, or human PLD. In both cases, the obtained molecules are piperidinyl-benzimidazolone derivatives, thereby allowing to propose this family of molecules as a novel source of inspiration for the search of compounds interfering with glycerolipid metabolism, that could be useful for other biological and therapeutics contexts.

  18. Bcl-2 induces cyclin D1 promoter activity in human breast epithelial cells independent of cell anchorage.

    PubMed

    Lin, H M; Lee, Y J; Li, G; Pestell, R G; Kim, H R

    2001-01-01

    Cyclin D1 expression is co-regulated by growth factor and cell adhesion signaling. Cell adhesion to the extracellular matrix activates focal adhesion kinase (FAK), which is essential for cyclin D1 expression. Upon the loss of cell adhesion, cyclin D1 expression is downregulated, followed by apoptosis in normal epithelial cells. Since bcl-2 prevents apoptosis induced by the loss of cell adhesion, we hypothesized that bcl-2 induces survival signaling complementary to cell adhesion-mediated gene regulation. In the present study, we investigated the role of bcl-2 on FAK activity and cyclin D1 expression. We found that bcl-2 overexpression induces cyclin D1 expression in human breast epithelial cell line MCF10A independent of cell anchorage. Increased cyclin D1 expression in stable bcl-2 transfectants is not related to bcl-2-increased G1 duration, but results from cyclin D1 promoter activation. Transient transfection studies confirmed anchorage-independent bcl-2 induction of cyclin D1 promoter activity in human breast epithelial cell lines (MCF10A, BT549, and MCF-7). We provide evidence that bcl-2 induction of cyclin D1 expression involves constitutive activation of focal adhesion kinase, regardless of cell adhesion. The present study suggests a potential oncogenic activity for bcl-2 through cyclin D1 induction, and provides an insight into the distinct proliferation-independent pathway leading to increased cyclin D1 expression in breast cancer.

  19. Overexpressed EDIL3 predicts poor prognosis and promotes anchorage-independent tumor growth in human pancreatic cancer

    PubMed Central

    Feng, Ming-Xuan; Wang, Ya-Hui; Yang, Xiao-Mei; He, Ping; Tian, Guang-Ang; Zhang, Xiao-Xin; Li, Qing; Cao, Xiao-Yan; Huo, Yan-Miao; Yang, Min-Wei; Fu, Xue-Liang; Li, Jiao; Liu, De-Jun; Dai, Miao; Wen, Shan-Yun; Gu, Jian-Ren; Hong, Jie; Hua, Rong; Zhang, Zhi-Gang; Sun, Yong-Wei

    2016-01-01

    Epidermal Growth Factor-like repeats and Discoidin I-Like Domains 3 (EDIL3), an extracellular matrix (ECM) protein associated with vascular morphogenesis and remodeling, is commonly upregulated in multiple types of human cancers and correlates with tumor progression. However, its expression pattern and underlying cellular functions in pancreatic ductal adenocarcinoma (PDAC) remain largely unexplored. In current study, we observed that expression of EDIL3 was significantly up-regulated in PDAC compared with normal controls in both cell lines and clinical specimens. In addition, elevated EDIL3 expression was positively correlated with patients’ TNM stage and T classification. Kaplan-Meier analysis indicated that high EDIL3 expression was significantly associated with shorter overall survival times in PDAC patients. Multivariate Cox regression analysis confirmed EDIL3 expression, age, lymph node metastasis and histological differentiation as independent prognostic factors in PDAC. Knockdown of EDIL3 showed no significant influence on cell viability, migration, invasion and starvation-induced apoptosis, but compromised anoikis resistance and anchorage independent tumor growth of PDAC cells. Meanwhile, treatment with recombinant EDIL3 protein markedly promoted anoikis resistance and anchorage independent tumor growth. Mechanistically, we demonstrated that altered protein expression of Bcl-2 family might contribute to the oncogenic activities of EDIL3. In conclusion, this study provides evidences that EDIL3 is a potential predictor and plays an important role in anchorage independent tumor growth of PDAC and EDIL3-related pathways might represent a novel therapeutic strategy for treatment of pancreatic cancer. PMID:26735172

  20. Human GLI-2 Is a Tat Activation Response Element-Independent Tat Cofactor

    PubMed Central

    Browning, Catherine M.; Smith, Michael J.; Clark, Nina M.; Lane, Brian R.; Parada, Camilo; Montano, Monty; KewalRamani, Vineet N.; Littman, Dan R.; Essex, Max; Roeder, Robert G.; Markovitz, David M.

    2001-01-01

    Zinc finger-containing GLI proteins are involved in the development of Caenorhabditis elegans, Xenopus, Drosophila, zebrafish, mice, and humans. In this study, we show that an isoform of human GLI-2 strongly synergizes with the Tat transactivating proteins of human immunodeficiency virus types 1 and 2 (HIV-1 and -2) and markedly stimulates viral replication. GLI-2 also synergizes with the previously described Tat cofactor cyclin T1 to stimulate Tat function. Surprisingly, GLI-2/Tat synergy is not dependent on either a typical GLI DNA binding site or an intact Tat activation response element but does require an intact TATA box. Thus, GLI-2/Tat synergy results from a mechanism of action which is novel both for a GLI protein and for a Tat cofactor. These findings link the GLI family of transcriptional and developmental regulatory proteins to Tat function and HIV replication. PMID:11160734

  1. ANGPTL4 expression induced by butyrate and rosiglitazone in human intestinal epithelial cells utilizes independent pathways.

    PubMed

    Korecka, Agata; de Wouters, Tomas; Cultrone, Antonietta; Lapaque, Nicolas; Pettersson, Sven; Doré, Joël; Blottière, Hervé M; Arulampalam, Velmurugesan

    2013-06-01

    Short-chain fatty acids (SCFAs), such as butyrate and propionate, are metabolic products of carbohydrate fermentation by the microbiota and constitute the main source of energy for host colonocytes. SCFAs are also important for gastrointestinal health, immunity, and host metabolism. Intestinally produced angiopoietin-like protein 4 (ANGPTL4) is a secreted protein with metabolism-altering properties and may offer a route by which microbiota can regulate host metabolism. Peroxisome proliferator-activated receptor (PPAR)-γ has previously been shown to be involved in microbiota-induced expression of intestinal ANGPTL4, but the role of bacterial metabolites in this process has remained elusive. Here, we show that the SCFA butyrate regulates intestinal ANGPTL4 expression in a PPAR-γ-independent manner. Although PPAR-γ is not required for butyrate-driven intestinal ANGPTL4 expression, costimulating with PPAR-γ ligands and SCFAs leads to additive increases in ANGPTL4 levels. We suggest that PPAR-γ and butyrate rely on two separate regulatory sites, a PPAR-responsive element downstream the transcription start site and a butyrate-responsive element(s) within the promoter region, 0.5 kb upstream of the transcription start site. Furthermore, butyrate gavage and colonization with Clostridium tyrobutyricum, a SCFA producer, can independently induce expression of intestinal ANGPTL4 in germ-free mice. Thus, oral administration of SCFA or use of SCFA-producing bacteria may be additional routes to maintain intestinal ANGPTL4 levels for preventive nutrition or therapeutic purposes.

  2. Human Cryptochrome-1 Confers Light Independent Biological Activity in Transgenic Drosophila Correlated with Flavin Radical Stability

    PubMed Central

    Vieira, Jacqueline; Jones, Alex R.; Danon, Antoine; Sakuma, Michiyo; Hoang, Nathalie; Robles, David; Tait, Shirley; Heyes, Derren J.; Picot, Marie; Yoshii, Taishi; Helfrich-Förster, Charlotte; Soubigou, Guillaume; Coppee, Jean-Yves; Klarsfeld, André; Rouyer, Francois; Scrutton, Nigel S.; Ahmad, Margaret

    2012-01-01

    Cryptochromes are conserved flavoprotein receptors found throughout the biological kingdom with diversified roles in plant development and entrainment of the circadian clock in animals. Light perception is proposed to occur through flavin radical formation that correlates with biological activity in vivo in both plants and Drosophila. By contrast, mammalian (Type II) cryptochromes regulate the circadian clock independently of light, raising the fundamental question of whether mammalian cryptochromes have evolved entirely distinct signaling mechanisms. Here we show by developmental and transcriptome analysis that Homo sapiens cryptochrome - 1 (HsCRY1) confers biological activity in transgenic expressing Drosophila in darkness, that can in some cases be further stimulated by light. In contrast to all other cryptochromes, purified recombinant HsCRY1 protein was stably isolated in the anionic radical flavin state, containing only a small proportion of oxidized flavin which could be reduced by illumination. We conclude that animal Type I and Type II cryptochromes may both have signaling mechanisms involving formation of a flavin radical signaling state, and that light independent activity of Type II cryptochromes is a consequence of dark accumulation of this redox form in vivo rather than of a fundamental difference in signaling mechanism. PMID:22427812

  3. Sex hormone-binding globulin regulation of androgen bioactivity in vivo: validation of the free hormone hypothesis

    PubMed Central

    Laurent, Michaël R.; Hammond, Geoffrey L.; Blokland, Marco; Jardí, Ferran; Antonio, Leen; Dubois, Vanessa; Khalil, Rougin; Sterk, Saskia S.; Gielen, Evelien; Decallonne, Brigitte; Carmeliet, Geert; Kaufman, Jean-Marc; Fiers, Tom; Huhtaniemi, Ilpo T.; Vanderschueren, Dirk; Claessens, Frank

    2016-01-01

    Sex hormone-binding globulin (SHBG) is the high-affinity binding protein for androgens and estrogens. According to the free hormone hypothesis, SHBG modulates the bioactivity of sex steroids by limiting their diffusion into target tissues. Still, the in vivo physiological role of circulating SHBG remains unclear, especially since mice and rats lack circulating SHBG post-natally. To test the free hormone hypothesis in vivo, we examined total and free sex steroid concentrations and bioactivity on target organs in mice expressing a human SHBG transgene. SHBG increased total androgen and estrogen concentrations via hypothalamic-pituitary feedback regulation and prolonged ligand half-life. Despite markedly raised total sex steroid concentrations, free testosterone was unaffected while sex steroid bioactivity on male and female reproductive organs was attenuated. This occurred via a ligand-dependent, genotype-independent mechanism according to in vitro seminal vesicle organ cultures. These results provide compelling support for the determination of free or bioavailable sex steroid concentrations in medicine, and clarify important comparative differences between translational mouse models and human endocrinology. PMID:27748448

  4. A novel nuclear role for the Vav3 nucleotide exchange factor in androgen receptor coactivation in prostate cancer.

    PubMed

    Rao, S; Lyons, L S; Fahrenholtz, C D; Wu, F; Farooq, A; Balkan, W; Burnstein, K L

    2012-02-01

    Increased androgen receptor (AR) transcriptional activity mediated by coactivator proteins may drive castration-resistant prostate cancer (CRPC) growth. Vav3, a Rho GTPase guanine nucleotide exchange factor (GEF), is overexpressed in human prostate cancers, particularly in models of CRPC progression. Vav3 coactivates AR in a Vav3 pleckstrin homology (PH) domain-dependent but GEF-independent manner. Ectopic expression of Vav3 in androgen-dependent human prostate cancer cells conferred robust castration-resistant xenograft tumor growth. Vav3 but not a Vav3 PH mutant greatly stimulated interaction between the AR amino and carboxyl termini (N-C interaction), which is required for maximal receptor transcriptional activity. Vav3 was distributed between the cytoplasm and nucleus with nuclear localization-dependent on the Vav3 PH domain. Membrane targeting of Vav3 abolished Vav3 potentiation of AR activity, whereas nuclear targeting of a Vav3 PH mutant rescued AR coactivation, suggesting that nuclear localization is an important function of the Vav3 PH domain. A nuclear role for Vav3 was further demonstrated by sequential chromatin immunoprecipitation assays, which revealed that Vav3 and AR were recruited to the same transcriptional complexes of an AR target gene enhancer. These data demonstrate the importance of Vav3 in CRPC and define a novel nuclear function of Vav3 in regulating AR activity.

  5. Androgen Withdrawal Fails to Induce Detectable Tissue Hypoxia in the Rat Prostate

    PubMed Central

    Regter, Sietze; Hedayati, Mohammad; Zhang, Yonggang; Zhou, Haoming; Dalrymple, Susan; Koch, Cameron J.; Isaacs, John T.; DeWeese, Theodore L.

    2015-01-01

    BACKGROUND It has been reported that significant hypoxia may occur in the rat prostate following androgen deprivation (AD). It is well known that hypoxia substantially reduces radiation sensitivity of cells both in vitro and in vivo. Given that contemporary management of men with intermediate and high-risk prostate cancer includes the use of neoadjuvant androgen suppression and radiation, AD-induced hypoxia in the prostate could result in suboptimal therapeutic results. Given this concern, we fully investigate possible AD-induced hypoxia in the ventral prostate (VP) of adult rats by two independent methods. METHODS Tissue pO2 levels in the VP of adult Spraque-Dawley rats were evaluated prior to and at various time points following castration by two independent techniques. First, an Oxylab tissue oxygen monitor with a 240 μm probe was used for quantitative monitoring of global VP oxygenation. Second, fluorescence immunohistochemistry using the hypoxia marker EF5, known to be metabolically activated by hypoxic cells, was used to evaluate cell-to-cell variation in hypoxia at various days post-castration. RESULTS Neither the oxygen probe nor EF5 method demonstrate any substantive change in pO2 levels in the rat VP at any time point post-castration. CONCLUSIONS We find no evidence that the rat VP becomes hypoxic at any point following castration using an animal model that closely mimics the human prostate. These data are in contrast to previous reports suggesting prostatic hypoxia occurs following AD and provide assurance that our present therapeutic strategy of neoadjuvant AD followed by radiation is not compromised by AD-induced tissue hypoxia. PMID:24677180

  6. Androgen and FSH synergistically stimulate lipoprotein degradation and utilization by ovary granulosa cells

    SciTech Connect

    Schreiber, J.R.; Nakamura, K.; Schmit, V.; Weinstein, D.B.

    1984-01-01

    Androgen can directly modulate the induction of steroidogenic enzymes by FSH (follicle stimulating hormone) in ovary granulosa cells. In studies of its mechanism of action, the authors examined the androgen effect on granulosa cell interaction with lipoproteins, the physiologic source of cholesterol. After granulosa cells were cultured for 48 hours with and without androgen and/or FSH, the cells were incubated for 24 hours with /sup 125/I-lipoproteins (human high density lipoprotein (HDL), rat HDL, or human low density lipoprotein (LDL)). The media were then analyzed for lipoprotein protein coat degradation products (mainly /sup 125/I-monoiodotyrosine) and progestin (mainly 20 alpha-dihydroprogesterone (20 alpha-DHP)). In the absence of FSH and androgen, 2 X 10(5) granulosa cells degraded basal levels of all three lipoproteins, but produced no measurable 20 alpha-DHP. The addition of 10(-7) M androstenedione (A), testosterone (T), or 5 alpha-dihydrotestosterone (DHT) had no effect on lipoprotein protein degradation or 20 alpha-DHP production. FSH alone stimulated lipoprotein protein degradation by 50 to 300% while the addition of androgen synergistically augmented the FSH-stimulated 20 alpha-DHP production as well as protein coat degradation of all three lipoproteins. DHT and T were both effective, indicating that androgens themselves, and not estrogen products, were responsible for the effect on lipoprotein protein degradation and 20 alpha-DHP production.

  7. Dickkopf-1 induced apoptosis in human placental choriocarcinoma is independent of canonical Wnt signaling

    SciTech Connect

    Peng Sha; Miao Chenglin; Li Jing; Fan Xiujun; Cao Yujing; Duan Enkui . E-mail: duane@ioz.ac.cn

    2006-11-24

    Placental choriocarcinoma, a reproductive system carcinoma in women, has about 0.81% occurrence frequency in China, which leads to over 90% lethality due to indistinct pathogenesis and the absence of efficient therapeutic treatment. In the present study, using immunostaining and reverse transcription PCR, we reported that Dickkopf-1 (Dkk-1) is prominently expressed in human cytotrophoblast (CTB) cell, but absent in the human placental choriocarcinoma cell line JAR and JEG3, implicating an unknown correlation between Dkk-1 and carcinogenesis of placental choriocarcinoma. Further, through exogenous introduction of Dkk-1, we found repressed proliferation in JAR and JEG3, induced apoptosis in JAR, and discovered significant tumor suppression effects of Dkk-1 in placental choriocarcinoma. Moreover we found that this function of Dkk-1 is achieved through c-Jun N-terminal kinase (JNK), whereas the canonical Wnt pathway may not have a great role. This discovery is not symphonic to previous functional understanding of Dkk-1, a canonical Wnt signaling antagonist. Together, our data indicate the possible correlation between Dkk-1 and human placental choriocarcinoma and suggest potential applications of Dkk-1 in treatment of human placental choriocarcinomas.

  8. Animate and Inanimate Objects in Human Visual Cortex: Evidence for Task-Independent Category Effects

    ERIC Educational Resources Information Center

    Wiggett, Alison J.; Pritchard, Iwan C.; Downing, Paul E.

    2009-01-01

    Evidence from neuropsychology suggests that the distinction between animate and inanimate kinds is fundamental to human cognition. Previous neuroimaging studies have reported that viewing animate objects activates ventrolateral visual brain regions, whereas inanimate objects activate ventromedial regions. However, these studies have typically…

  9. Prenatal glucocorticoids and maternal smoking during pregnancy independently program adult nicotine dependence in daughters: A 40-year prospective study

    PubMed Central

    Stroud, Laura R.; Papandonatos, George; Shenassa, Edmond; Rodriguez, Daniel; Niaura, Raymond; LeWinn, Kaja; Lipsitt, Lewis P.; Buka, Stephen L.

    2013-01-01

    Background Maternal smoking during pregnancy (MSDP) is an independent risk factor for offspring nicotine dependence (ND), but mechanisms remain unknown. We investigated prenatal glucocorticoid (cortisol) and androgen (testosterone) associations with offspring ND over 40 years, and the possibility that prenatal glucocorticoids and androgens would mediate links between MSDP and offspring ND. Methods Participants were 1,086 mother-adult offspring pairs (59% female) from the New England Family Study, a 40-year longitudinal follow up of the Collaborative Perinatal Project. MSDP was assessed prospectively at each prenatal visit. Maternal cortisol, testosterone, and cotinine (nicotine metabolite), were assayed from third trimester maternal sera. Offspring lifetime ND was assessed via structured interview. Results Significant bivariate associations emerged for: a) MSDP/cotinine and lifetime ND, and b) maternal cortisol and lifetime ND, for daughters only. In multivariate models, maternal cortisol and MSDP/cotinine remained significantly and independently associated with increased odds of daughters’ lifetime ND. However, cortisol did not mediate the MSDP-lifetime ND relation. No associations emerged between maternal testosterone and offspring ND. Conclusions Results provide the first evidence in support of prenatal glucocorticoid programming of adult ND over 40 years in daughters only. Our study highlights two independent prenatal pathways leading to increased risk for ND in daughters: elevated prenatal glucocorticoids and MSDP/nicotine exposure. Daughter-specific effects of glucocorticoid and MSDP programming over 40 years highlight the breadth and persistence of sexually dimorphic programming effects in humans. Results do not support androgen programming of offspring ND. PMID:24034414

  10. Independent component analysis of noninvasively recorded cortical magnetic DC-fields in humans.

    PubMed

    Wübbeler, G; Ziehe, A; Mackert, B M; Müller, K R; Trahms, L; Curio, G

    2000-05-01

    We apply a recently developed multivariate statistical data analysis technique--so called blind source separation (BSS) by independent component analysis--to process magnetoencephalogram recordings of near-dc fields. The extraction of near-dc fields from MEG recordings has great relevance for medical applications since slowly varying dc-phenomena have been found, e.g., in cerebral anoxia and spreading depression in animals. Comparing several BSS approaches, it turns out that an algorithm based on temporal decorrelation successfully extracted a dc-component which was induced in the auditory cortex by presentation of music. The task is challenging because of the limited amount of available data and the corruption by outliers, which makes it an interesting real-world testbed for studying the robustness of ICA methods.

  11. Emergence of CD4 Independence Envelopes and Astrocyte Infection in R5 Simian-Human Immunodeficiency Virus Model of Encephalitis

    PubMed Central

    Zhuang, Ke; Leda, Ana Rachel; Tsai, Lily; Knight, Heather; Harbison, Carole; Gettie, Agegnehu; Blanchard, James; Westmoreland, Susan

    2014-01-01

    ABSTRACT Human immunodeficiency virus type 1 (HIV-1) infection in the central nervous system (CNS) is characterized by replication in macrophages or brain microglia that express low levels of the CD4 receptor and is the cause of HIV-associated dementia and related cognitive and motor disorders that affect 20 to 30% of treatment-naive patients with AIDS. Independent viral envelope evolution in the brain has been reported, with the need for robust replication in resident CD4low cells, as well as CD4-negative cells, such as astrocytes, proposed as a major selective pressure. We previously reported giant-cell encephalitis in subtype B and C R5 simian-human immunodeficiency virus (SHIV)-infected macaques (SHIV-induced encephalitis [SHIVE]) that experienced very high chronic viral loads and progressed rapidly to AIDS, with varying degrees of macrophage or microglia infection and activation of these immune cells, as well as astrocytes, in the CNS. In this study, we characterized envelopes (Env) amplified from the brains of subtype B and C R5 SHIVE macaques. We obtained data in support of an association between severe neuropathological changes, robust macrophage and microglia infection, and evolution to CD4 independence. Moreover, the degree of Env CD4 independence appeared to correlate with the extent of astrocyte infection in vivo. These findings further our knowledge of the CNS viral population phenotypes that are associated with the severity of HIV/SHIV-induced neurological injury and improve our understanding of the mechanism of HIV-1 cellular tropism and persistence in the brain. IMPORTANCE Human immunodeficiency virus type 1 (HIV-1) infection of astrocytes in the brain has been suggested to be important in HIV persistence and neuropathogenesis but has not been definitively demonstrated in an animal model of HIV-induced encephalitis (HIVE). Here, we describe a new nonhuman primate (NHP) model of R5 simian-human immunodeficiency virus (SHIV)-induced encephalitis

  12. Phenotype-independent effects of retroviral transduction in human dental pulp stem cells.

    PubMed

    Egbuniwe, Obi; Grant, Andrew D; Renton, Tara; Di Silvio, Lucy

    2013-07-01

    An immortalized human dental pulp stem cell (DPSC) line of an odontoblastic phenotype is established to circumvent the normal programmed senescence and to maintain the cell line's usefulness as a tool for further study of cellular activity. DPSCs are isolated from human dental pulp tissues and transfected using hTERT. The influence of this process on the DPSC phenotype and the mRNA expression of oncogenes involved in cellular senescence is investigated. The results reveal an absence of altered DPSC morphology and phenotype following the exogenous introduction of the hTERT gene, which is coupled with a significant reduction in p16 mRNA expression. This provides insight into how to circumvent in vitro dental pulp stem cell death following the exogenous introduction of hTERT.

  13. Anti-inflammatory effects of Perilla frutescens in activated human neutrophils through two independent pathways: Src family kinases and Calcium

    PubMed Central

    Chen, Chun-Yu; Leu, Yann-Lii; Fang, Yu; Lin, Chwan-Fwu; Kuo, Liang-Mou; Sung, Wei-Che; Tsai, Yung-Fong; Chung, Pei-Jen; Lee, Ming-Chung; Kuo, Yu-Ting; Yang, Hsuan-Wu; Hwang, Tsong-Long

    2015-01-01

    The leaves of Perilla frutescens (L.) Britt. have been traditionally used as an herbal medicine in East Asian countries to treat a variety diseases. In this present study, we investigated the inhibitory effects of P. frutescens extract (PFE) on N-formyl-Met-Leu-Phe (fMLF)-stimulated human neutrophils and the underlying mechanisms. PFE (1, 3, and 10 μg/ml) inhibited superoxide anion production, elastase release, reactive oxygen species formation, CD11b expression, and cell migration in fMLF-activated human neutrophils in dose-dependent manners. PFE inhibited fMLF-induced phosphorylation of the Src family kinases (SFKs), Src (Tyr416) and Lyn (Tyr396), and reduced their enzymatic activities. Both PFE and PP2 (a selective inhibitor of SFKs) reduced the phosphorylation of Burton’s tyrosine kinases (Tyr223) and Vav (Tyr174) in fMLF-activated human neutrophils. Additionally, PFE decreased intracellular Ca2+ levels ([Ca2+]i), whereas PP2 prolonged the time required for [Ca2+]i to return to its basal level. Our findings indicated that PFE effectively regulated the inflammatory activities of fMLF-activated human neutrophils. The anti-inflammatory effects of PFE on activated human neutrophils were mediated through two independent signaling pathways involving SFKs (Src and Lyn) and mobilization of intracellular Ca2+. PMID:26659126

  14. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin

    PubMed Central

    Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J.; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F.; Psathaki, Olympia E.; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R.; Schlenke, Peter; Zaehres, Holm

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34+ hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34+ hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34+ hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34+ cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. PMID:25326431

  15. Androgens affect muscle, motor neuron, and survival in a mouse model of SOD1-related amyotrophic lateral sclerosis.

    PubMed

    Aggarwal, Tanya; Polanco, Maria J; Scaramuzzino, Chiara; Rocchi, Anna; Milioto, Carmelo; Emionite, Laura; Ognio, Emanuela; Sambataro, Fabio; Galbiati, Mariarita; Poletti, Angelo; Pennuto, Maria

    2014-08-01

    Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by selective loss of upper and lower motor neurons and skeletal muscle atrophy. Epidemiologic and experimental evidence suggest the involvement of androgens in ALS pathogenesis, but the mechanism through which androgens modify the ALS phenotype is unknown. Here, we show that androgen ablation by surgical castration extends survival and disease duration of a transgenic mouse model of ALS expressing mutant human SOD1 (hSOD1-G93A). Furthermore, long-term treatment of orchiectomized hSOD1-G93A mice with nandrolone decanoate (ND), an anabolic androgenic steroid, worsened disease manifestations. ND treatment induced muscle fiber hypertrophy but caused motor neuron death. ND negatively affected survival, thereby dissociating skeletal muscle pathology from life span in this ALS mouse model. Interestingly, orchiectomy decreased androgen receptor levels in the spinal cord and muscle, whereas ND treatment had the opposite effect. Notably, stimulation with ND promoted the recruitment of endogenous androgen receptor into biochemical complexes that were insoluble in sodium dodecyl sulfate, a finding consistent with protein aggregation. Overall, our results shed light on the role of androgens as modifiers of ALS pathogenesis via dysregulation of androgen receptor homeostasis.

  16. 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

  17. Induction of human adiponectin gene transcription by telmisartan, angiotensin receptor blocker, independently on PPAR-{gamma} activation

    SciTech Connect

    Moriuchi, Akie ||. E-mail: f1195@cc.nagasaki-u-ac.jp; Shimamura, Mika; Kita, Atsushi; Kuwahara, Hironaga; Satoh, Tsuyoshi; Satoh, Tsuyoshi; Fujishima, Keiichiro; Fukushima, Keiko |; Hayakawa, Takao; Mizuguchi, Hiroyuki; Nagayama, Yuji; Kawasaki, Eiji

    2007-05-18

    Adiponectin, an adipose tissue-specific plasma protein, has been shown to ameliorate insulin resistance and inhibit the process of atherosclerosis. Recently, several reports have stated that angiotensin type 1 receptor blockers (ARBs), increase adiponectin plasma level, and ameliorate insulin resistance. Telmisartan, a subclass of ARBs, has been shown to be a partial agonist of the peroxisome proliferator-activated receptor (PPAR)-{gamma}, and to increase the plasma adiponectin level. However, the transcriptional regulation of the human adiponectin gene by telmisartan has not been determined yet. To elucidate the effect of telmisartan on adiponectin, the stimulatory regulation of human adiponectin gene by telmisartan was investigated in 3T3-L1 adipocytes, utilizing adenovirus-mediated luciferase reporter gene-transferring technique. This study indicates that telmisartan may stimulate adiponectin transcription independent of PPAR-{gamma}.

  18. Modeling Truncated AR Expression in a Natural Androgen Responsive Environment and Identification of RHOB as a Direct Transcriptional Target

    PubMed Central

    Tsai, Hui-Chi; Boucher, David L.; Martinez, Anthony; Tepper, Clifford G.; Kung, Hsing-Jien

    2012-01-01

    Recent studies identifying putative truncated androgen receptor isoforms with ligand-independent activity have shed new light on the acquisition of androgen depletion independent (ADI) growth of prostate cancer. In this study, we present a model system in which a C-terminally truncated variant of androgen receptor (TC-AR) is inducibly expressed in LNCaP, an androgen-dependent cell line, which expresses little truncated receptor. We observed that when TC-AR is overexpressed, the endogenous full length receptor (FL-AR) is transcriptionally downmodulated. This in essence allows us to “replace” FL-AR with TC-AR and compare their individual properties in exactly the same genetic and cellular background, which has not been performed before. We show that the TC-AR translocates to the nucleus, activates transcription of AR target genes in the absence of DHT and is sufficient to confer ADI growth to the normally androgen dependent LNCaP line. We also show that while there is significant overlap in the genes regulated by FL- and TC-AR there are also differences in the respective suites of target genes with each AR form regulating genes that the other does not. Among the genes uniquely activated by TC-AR is RHOB which is shown to be involved in the increased migration and morphological changes observed in LN/TC-AR, suggesting a role of RHOB in the regulation of androgen-independent behavior of prostate cancer cells. PMID:23209612

  19. Regulation of the transcriptional coactivator FHL2 licenses activation of the androgen receptor in castrate-resistant prostate cancer.

    PubMed

    McGrath, Meagan J; Binge, Lauren C; Sriratana, Absorn; Wang, Hong; Robinson, Paul A; Pook, David; Fedele, Clare G; Brown, Susan; Dyson, Jennifer M; Cottle, Denny L; Cowling, Belinda S; Niranjan, Birunthi; Risbridger, Gail P; Mitchell, Christina A

    2013-08-15

    It is now clear that progression from localized prostate cancer to incurable castrate-resistant prostate cancer (CRPC) is driven by continued androgen receptor (AR), signaling independently of androgen. Thus, there remains a strong rationale to suppress AR activity as the single most important therapeutic goal in CRPC treatment. Although the expression of ligand-independent AR splice variants confers resistance to AR-targeted therapy and progression to lethal castrate-resistant cancer, the molecular regulators of AR activity in CRPC remain unclear, in particular those pathways that potentiate the function of mutant AR in CRPC. Here, we identify FHL2 as a novel coactivator of ligand-independent AR variants that are important in CRPC. We show that the nuclear localization of FHL2 and coactivation of the AR is driven by calpain cleavage of the cytoskeletal protein filamin, a pathway that shows differential activation in prostate epithelial versus prostate cancer cell lines. We further identify a novel FHL2-AR-filamin transcription complex, revealing how deregulation of this axis promotes the constitutive, ligand-independent activation of AR variants, which are present in CRPC. Critically, the calpain-cleaved filamin fragment and FHL2 are present in the nucleus only in CRPC and not benign prostate tissue or localized prostate cancer. Thus, our work provides mechanistic insight into the enhanced AR activation, most notably of the recently identified AR variants, including AR-V7 that drives CRPC progression. Furthermore, our results identify the first disease-specific mechanism for deregulation of FHL2 nuclear localization during cancer progression. These results offer general import beyond prostate cancer, given that nuclear FHL2 is characteristic of other human cancers where oncogenic transcription factors that drive disease are activated like the AR in prostate cancer.

  20. Type 2 Diabetes Biomarkers of Human Gut Microbiota Selected via Iterative Sure Independent Screening Method

    PubMed Central

    Li, Dongfang; Zhou, Ke; Zou, Fuhao

    2015-01-01

    Type 2 diabetes, which is a complex metabolic disease influenced by genetic and environment, has become a worldwide problem. Previous published results focused on genetic components through genome-wide association studies that just interpret this disease to some extent. Recently, two research groups published metagenome-wide association studies (MGWAS) result that found meta-biomarkers related with type 2 diabetes. However, One key problem of analyzing genomic data is that how to deal with the ultra-high dimensionality of features. From a statistical viewpoint it is challenging to filter true factors in high dimensional data. Various methods and techniques have been proposed on this issue, which can only achieve limited prediction performance and poor interpretability. New statistical procedure with higher performance and clear interpretability is appealing in analyzing high dimensional data. To address this problem, we apply an excellent statistical variable selection procedure called iterative sure independence screening to gene profiles that obtained from metagenome sequencing, and 48/24 meta-markers were selected in Chinese/European cohorts as predictors with 0.97/0.99 accuracy in AUC (area under the curve), which showed a better performance than other model selection methods, respectively. These results demonstrate the power and utility of data mining technologies within the large-scale and ultra-high dimensional genomic-related dataset for diagnostic and predictive markers identifying. PMID:26479726

  1. 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

  2. Isolation of reovirus T3D mutants capable of infecting human tumor cells independent of junction adhesion molecule-A.

    PubMed

    van den Wollenberg, Diana J M; Dautzenberg, Iris J C; van den Hengel, Sanne K; Cramer, Steve J; de Groot, Raoul J; Hoeben, Rob C

    2012-01-01

    Mammalian Reovirus is a double-stranded RNA virus with a distinctive preference to replicate in and lyse transformed cells. On that account, Reovirus type 3 Dearing (T3D) is clinically evaluated as oncolytic agent. The therapeutic efficacy of this approach depends in part on the accessibility of the reovirus receptor Junction Adhesion Molecule-A (JAM-A) on the target cells. Here, we describe the isolation and characterization of reovirus T3D mutants that can infect human tumor cells independent of JAM-A. The JAM-A-independent (jin) mutants were isolated on human U118MG glioblastoma cells, which do not express JAM-A. All jin mutants harbour mutations in the S1 segments close to the region that encodes the sialic acid-binding pocket in the shaft of the spike protein. In addition, two of the jin mutants encode spike proteins with a Q336R substitution in their head domain. The jin mutants can productively infect a wide range of cell lines that resist wt reovirus T3D infection, including chicken LMH cells, hamster CHO cells, murine endothelioma cells, human U2OS and STA-ET2.1 cells, but not primary human fibroblasts. The jin-mutants rely on the presence of sialic-acid residues on the cell surface for productive infection, as is evident from wheat germ agglutinin (WGA) inhibition experiments, and from the jin-reovirus resistance of CHO-Lec2 cells, which have a deficiency of sialic-acids on their glycoproteins. The jin mutants may be useful as oncolytic agents for use in tumors in which JAM-A is absent or inaccessible.

  3. Isolation of Reovirus T3D Mutants Capable of Infecting Human Tumor Cells Independent of Junction Adhesion Molecule-A

    PubMed Central

    van den Hengel, Sanne K.; Cramer, Steve J.; de Groot, Raoul J.; Hoeben, Rob C.

    2012-01-01

    Mammalian Reovirus is a double-stranded RNA virus with a distinctive preference to replicate in and lyse transformed cells. On that account, Reovirus type 3 Dearing (T3D) is clinically evaluated as oncolytic agent. The therapeutic efficacy of this approach depends in part on the accessibility of the reovirus receptor Junction Adhesion Molecule-A (JAM-A) on the target cells. Here, we describe the isolation and characterization of reovirus T3D mutants that can infect human tumor cells independent of JAM-A. The JAM-A-independent (jin) mutants were isolated on human U118MG glioblastoma cells, which do not express JAM-A. All jin mutants harbour mutations in the S1 segments close to the region that encodes the sialic acid-binding pocket in the shaft of the spike protein. In addition, two of the jin mutants encode spike proteins with a Q336R substitution in their head domain. The jin mutants can productively infect a wide range of cell lines that resist wt reovirus T3D infection, including chicken LMH cells, hamster CHO cells, murine endothelioma cells, human U2OS and STA-ET2.1 cells, but not primary human fibroblasts. The jin-mutants rely on the presence of sialic-acid residues on the cell surface for productive infection, as is evident from wheat germ agglutinin (WGA) inhibition experiments, and from the jin-reovirus resistance of CHO-Lec2 cells, which have a deficiency of sialic-acids on their glycoproteins. The jin mutants may be useful as oncolytic agents for use in tumors in which JAM-A is absent or inaccessible. PMID:23110175

  4. Different human vaccine adjuvants promote distinct antigen-independent immunological signatures tailored to different pathogens

    PubMed Central

    Knudsen, Niels Peter H.; Olsen, Anja; Buonsanti, Cecilia; Follmann, Frank; Zhang, Yuan; Coler, Rhea N.; Fox, Christopher B.; Meinke, Andreas; D´Oro, Ugo; Casini, Daniele; Bonci, Alessandra; Billeskov, Rolf; De Gregorio, Ennio; Rappuoli, Rino; Harandi, Ali M.; Andersen, Peter; Agger, Else Marie

    2016-01-01

    The majority of vaccine candidates in clinical development are highly purified proteins and peptides relying on adjuvants to enhance and/or direct immune responses. Despite the acknowledged need for novel adjuvants, there are still very few adjuvants in licensed human vaccines. A vast number of adjuvants have been tested pre-clinically using different experimental conditions, rendering it impossible to directly compare their activity. We performed a head-to-head comparison of five different adjuvants Alum, MF59®, GLA-SE, IC31® and CAF01 in mice and combined these with antigens from M. tuberculosis, influenza, and chlamydia to test immune-profiles and efficacy in infection models using standardized protocols. Regardless of antigen, each adjuvant had a unique immunological signature suggesting that the adjuvants have potential for different disease targets. Alum increased antibody titers; MF59® induced strong antibody and IL-5 responses; GLA-SE induced antibodies and Th1; CAF01 showed a mixed Th1/Th17 profile and IC31® induced strong Th1 responses. MF59® and GLA-SE were strong inducers of influenza HI titers while CAF01, GLA-SE and IC31® enhanced protection to TB and chlamydia. Importantly, this is the first extensive attempt to categorize clinical-grade adjuvants based on their immune profiles and protective efficacy to inform a rational development of next generation vaccines for human use. PMID:26791076

  5. Exploiting independent filter bandwidth of human factor cepstral coefficients in automatic speech recognition

    NASA Astrophysics Data System (ADS)

    Skowronski, Mark D.; Harris, John G.

    2004-09-01

    Mel frequency cepstral coefficients (MFCC) are the most widely used speech features in automatic speech recognition systems, primarily because the coefficients fit well with the assumptions used in hidden Markov models and because of the superior noise robustness of MFCC over alternative feature sets such as linear prediction-based coefficients. The authors have recently introduced human factor cepstral coefficients (HFCC), a modification of MFCC that uses the known relationship between center frequency and critical bandwidth from human psychoacoustics to decouple filter bandwidth from filter spacing. In this work, the authors introduce a variation of HFCC called HFCC-E in which filter bandwidth is linearly scaled in order to investigate the effects of wider filter bandwidth on noise robustness. Experimental results show an increase in signal-to-noise ratio of 7 dB over traditional MFCC algorithms when filter bandwidth increases in HFCC-E. An important attribute of both HFCC and HFCC-E is that the algorithms only differ from MFCC in the filter bank coefficients: increased noise robustness using wider filters is achieved with no additional computational cost.

  6. Exploiting independent filter bandwidth of human factor cepstral coefficients in automatic speech recognition.

    PubMed

    Skowronski, Mark D; Harris, John G

    2004-09-01

    Mel frequency cepstral coefficients (MFCC) are the most widely used speech features in automatic speech recognition systems, primarily because the coefficients fit well with the assumptions used in hidden Markov models and because of the superior noise robustness of MFCC over alternative feature sets such as linear prediction-based coefficients. The authors have recently introduced human factor cepstral coefficients (HFCC), a modification of MFCC that uses the known relationship between center frequency and critical bandwidth from human psychoacoustics to decouple filter bandwidth from filter spacing. In this work, the authors introduce a variation of HFCC called HFCC-E in which filter bandwidth is linearly scaled in order to investigate the effects of wider filter bandwidth on noise robustness. Experimental results show an increase in signal-to-noise ratio of 7 dB over traditional MFCC algorithms when filter bandwidth increases in HFCC-E. An important attribute of both HFCC and HFCC-E is that the algorithms only differ from MFCC in the filter bank coefficients: increased noise robustness using wider filters is achieved with no additional computational cost.

  7. Different human vaccine adjuvants promote distinct antigen-independent immunological signatures tailored to different pathogens.

    PubMed

    Knudsen, Niels Peter H; Olsen, Anja; Buonsanti, Cecilia; Follmann, Frank; Zhang, Yuan; Coler, Rhea N; Fox, Christopher B; Meinke, Andreas; D'Oro, Ugo; Casini, Daniele; Bonci, Alessandra; Billeskov, Rolf; De Gregorio, Ennio; Rappuoli, Rino; Harandi, Ali M; Andersen, Peter; Agger, Else Marie

    2016-01-01

    The majority of vaccine candidates in clinical development are highly purified proteins and peptides relying on adjuvants to enhance and/or direct immune responses. Despite the acknowledged need for novel adjuvants, there are still very few adjuvants in licensed human vaccines. A vast number of adjuvants have been tested pre-clinically using different experimental conditions, rendering it impossible to directly compare their activity. We performed a head-to-head comparison of five different adjuvants Alum, MF59®, GLA-SE, IC31® and CAF01 in mice and combined these with antigens from M. tuberculosis, influenza, and chlamydia to test immune-profiles and efficacy in infection models using standardized protocols. Regardless of antigen, each adjuvant had a unique immunological signature suggesting that the adjuvants have potential for different disease targets. Alum increased antibody titers; MF59® induced strong antibody and IL-5 responses; GLA-SE induced antibodies and Th1; CAF01 showed a mixed Th1/Th17 profile and IC31® induced strong Th1 responses. MF59® and GLA-SE were strong inducers of influenza HI titers while CAF01, GLA-SE and IC31® enhanced protection to TB and chlamydia. Importantly, this is the first extensive attempt to categorize clinical-grade adjuvants based on their immune profiles and protective efficacy to inform a rational development of next generation vaccines for human use. PMID:26791076

  8. 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

  9. Tensile stimuli increase nerve growth factor in human dermal fibroblasts independent of tension-induced TGFβ production.

    PubMed

    Kim, Mina; Shin, Dong Wook; Shin, Hyunjun; Noh, Minsoo; Shin, Jennifer H

    2013-01-01

    Human dermal fibroblasts (HDFs) regulate wound-healing processes in human skin, including the regeneration of skin sensory fibres, in response to various mechanical stimuli. Because nerve growth factor (NGF) has an essential role in sensory regeneration, we evaluated the possible association of NGF with mechanical stimulus-dependent cellular responses in HDFs. A cyclic tensile stimulus increased both NGF and transforming growth factor (TGF) β2 production, yet with different gene transcription and signal desensitization profiles. Neutralizing TGFβ with antibodies did not affect the tension-induced NGF upregulation, with significant inhibition of endogenous TGFβ2 transcription. The treatment with LY294002, SP600125 or U0126 hindered the tension-induced TGFβ2 upregulation, although the increase in NGF was regulated only by SP600125 or U0126, indicating the involvement of three signalling kinase pathways in the upregulation of TGFβ2. However, the upregulation of NGF was shown to be independent of PI3K, demonstrating the independent regulation of tension-induced NGF and TGFβ production in HDFs.

  10. How concepts are encoded in the human brain: A modality independent, category-based cortical organization of semantic knowledge.

    PubMed

    Handjaras, Giacomo; Ricciardi, Emiliano; Leo, Andrea; Lenci, Alessandro; Cecchetti, Luca; Cosottini, Mirco; Marotta, Giovanna; Pietrini, Pietro

    2016-07-15

    How conceptual knowledge is represented in the human brain remains to be determined. To address the differential role of low-level sensory-based and high-level abstract features in semantic processing, we combined behavioral studies of linguistic production and brain activity measures by functional magnetic resonance imaging in sighted and congenitally blind individuals while they performed a property-generation task with concrete nouns from eight categories, presented through visual and/or auditory modalities. Patterns of neural activity within a large semantic cortical network that comprised parahippocampal, lateral occipital, temporo-parieto-occipital and inferior parietal cortices correlated with linguistic production and were independent both from the modality of stimulus presentation (either visual or auditory) and the (lack of) visual experience. In contrast, selected modality-dependent differences were observed only when the analysis was limited to the individual regions within the semantic cortical network. We conclude that conceptual knowledge in the human brain relies on a distributed, modality-independent cortical representation that integrates the partial category and modality specific information retained at a regional level. PMID:27132545

  11. How concepts are encoded in the human brain: A modality independent, category-based cortical organization of semantic knowledge.

    PubMed

    Handjaras, Giacomo; Ricciardi, Emiliano; Leo, Andrea; Lenci, Alessandro; Cecchetti, Luca; Cosottini, Mirco; Marotta, Giovanna; Pietrini, Pietro

    2016-07-15

    How conceptual knowledge is represented in the human brain remains to be determined. To address the differential role of low-level sensory-based and high-level abstract features in semantic processing, we combined behavioral studies of linguistic production and brain activity measures by functional magnetic resonance imaging in sighted and congenitally blind individuals while they performed a property-generation task with concrete nouns from eight categories, presented through visual and/or auditory modalities. Patterns of neural activity within a large semantic cortical network that comprised parahippocampal, lateral occipital, temporo-parieto-occipital and inferior parietal cortices correlated with linguistic production and were independent both from the modality of stimulus presentation (either visual or auditory) and the (lack of) visual experience. In contrast, selected modality-dependent differences were observed only when the analysis was limited to the individual regions within the semantic cortical network. We conclude that conceptual knowledge in the human brain relies on a distributed, modality-independent cortical representation that integrates the partial category and modality specific information retained at a regional level.

  12. Role of manganese superoxide dismutase on growth and invasive properties of human estrogen-independent breast cancer cells.

    PubMed

    Kattan, Zilal; Minig, Vanessa; Leroy, Pierre; Dauça, Michel; Becuwe, Philippe

    2008-03-01

    Manganese superoxide dismutase (MnSOD) is known to play a role in cancer. MnSOD exerts a tumor suppressive effect in estrogen-dependent human breast cancer cells. In the present study we investigated the in vitro role of MnSOD in the growth of some aggressive and highly metastatic estrogen-independent breast cancer cells, i.e., MDA-MB231 and SKBR3 cells. We show that estrogen-independent cells expressed a significantly higher basal MnSOD level compared to estrogen-dependent human breast cancer cell lines (MCF-7 and T47D). For MDA-MB231 cells, the high-MnSOD level was accompanied by an overproduction of intracellular hydrogen peroxide (H2O2) and by a low expression of the major H2O2-detoxifying enzymes, catalase, and peroxiredoxin 3, compared to MCF-7 cells. Suppression of MnSOD expression by antisense RNA was associated with a decrease of H2O2 content and caused a stimulation of growth with a reduced cell doubling time but induced a decrease of colony formation. Furthermore, treatment of MDA-MB231 cells with H2O2 scavengers markedly reduced tumor cell growth and colony formation. In addition, MnSOD suppression or treatment with H2O2 scavengers reduced the invasive properties of MDA-MB231 cells up to 43%, with a concomitant decrease of metalloproteinase-9 activity. We conclude that MnSOD plays a role in regulating tumor cell growth and invasive properties of estrogen-independent metastatic breast cancer cells. These action are mediated by MnSOD-dependent H2O2 production. In addition, these results suggest that MnSOD up-regulation may be one mechanism that contributes to the development of metastatic breast cancers.

  13. Exercise and Serum Androgens in Women.

    ERIC Educational Resources Information Center

    Westerlind, Kim C.; And Others

    1987-01-01

    This study examining the effect of a 10-week hydraulic resistance exercise program on serum androgen levels, strength, and lean body weight in 18 college women revealed that training did not result in significant increases in androgen hormones, although there were significant gains in strength. (Author/CB)

  14. Contractile dysfunction in muscle may underlie androgen-dependent motor dysfunction in spinal bulbar muscular atrophy

    PubMed Central

    Oki, Kentaro; Halievski, Katherine; Vicente, Laura; Xu, Youfen; Zeolla, Donald; Poort, Jessica; Katsuno, Masahisa; Adachi, Hiroaki; Sobue, Gen; Wiseman, Robert W.; Breedlove, S. Marc

    2015-01-01

    Spinal and bulbar muscular atrophy (SBMA) is characterized by progressive muscle weakness linked to a polyglutamine expansion in the androgen receptor (AR). Current evidence indicates that mutant AR causes SBMA by acting in muscle to perturb its function. However, information about how muscle function is impaired is scant. One fundamental question is whether the intrinsic strength of muscles, an attribute of muscle independent of its mass, is affected. In the current study, we assess the contractile properties of hindlimb muscles in vitro from chronically diseased males of three different SBMA mouse models: a transgenic (Tg) model that broadly expresses a full-length human AR with 97 CAGs (97Q), a knock-in (KI) model that expresses a humanized AR containing a CAG expansion in the first exon, and a Tg myogenic model that overexpresses wild-type AR only in skeletal muscle fibers. We found that hindlimb muscles in the two Tg models (97Q and myogenic) showed marked losses in their intrinsic strength and resistance to fatigue, but were minimally affected in KI males. However, diseased muscles of all three models showed symptoms consistent with myotonic dystrophy type 1, namely, reduced resting membrane potential and deficits in chloride channel mRNA. These data indicate that muscle dysfunction is a core feature of SBMA caused by at least some of the same pathogenic mechanisms as myotonic dystrophy. Thus mechanisms controlling muscle function per se independent of mass are prime targets for SBMA therapeutics. PMID:25663674

  15. Contractile dysfunction in muscle may underlie androgen-dependent motor dysfunction in spinal bulbar muscular atrophy.

    PubMed

    Oki, Kentaro; Halievski, Katherine; Vicente, Laura; Xu, Youfen; Zeolla, Donald; Poort, Jessica; Katsuno, Masahisa; Adachi, Hiroaki; Sobue, Gen; Wiseman, Robert W; Breedlove, S Marc; Jordan, Cynthia L

    2015-04-01

    Spinal and bulbar muscular atrophy (SBMA) is characterized by progressive muscle weakness linked to a polyglutamine expansion in the androgen receptor (AR). Current evidence indicates that mutant AR causes SBMA by acting in muscle to perturb its function. However, information about how muscle function is impaired is scant. One fundamental question is whether the intrinsic strength of muscles, an attribute of muscle independent of its mass, is affected. In the current study, we assess the contractile properties of hindlimb muscles in vitro from chronically diseased males of three different SBMA mouse models: a transgenic (Tg) model that broadly expresses a full-length human AR with 97 CAGs (97Q), a knock-in (KI) model that expresses a humanized AR containing a CAG expansion in the first exon, and a Tg myogenic model that overexpresses wild-type AR only in skeletal muscle fibers. We found that hindlimb muscles in the two Tg models (97Q and myogenic) showed marked losses in their intrinsic strength and resistance to fatigue, but were minimally affected in KI males. However, diseased muscles of all three models showed symptoms consistent with myotonic dystrophy type 1, namely, reduced resting membrane potential and deficits in chloride channel mRNA. These data indicate that muscle dysfunction is a core feature of SBMA caused by at least some of the same pathogenic mechanisms as myotonic dystrophy. Thus mechanisms controlling muscle function per se independent of mass are prime targets for SBMA therapeutics.

  16. Cues to Androgens and Quality in Male Gibbon Songs

    PubMed Central

    Barelli, Claudia; Mundry, Roger; Heistermann, Michael; Hammerschmidt, Kurt

    2013-01-01

    Animal vocal signals may provide information about senders and mediate important social interactions like sexual competition, territory maintenance and mate selection. Hence, it is important to understand whether vocal signals provide accurate information about animal attributes or status. Gibbons are non-human primates that produce loud, distinctive and melodious vocalizations resembling more those of birds than of other non-human primates. Wild gibbons are characterized by flexibility in social organization (i.e., pairs and multimale units) as well as in mating system (i.e., monogamy and polyandry). Such features make them a suitable model to investigate whether the physiology (hormonal status) and socio-demographic features find their correspondence in the structure of their songs. By combining male solo song recordings, endocrine outputs using non-invasive fecal androgen measures and behavioral observations, we studied 14 groups (10 pair-living, 4 multimale) of wild white-handed gibbons (Hylobates lar) residing at Khao Yai National Park, Thailand. We collected a total of 322 fecal samples and recorded 48 songs from 18 adult animals. Our results confirmed inter-individuality in male gibbon songs, and showed a clear correlation between androgen levels and song structures. Gibbons with higher androgen levels produced calls having higher pitch, and similarly adult individuals produced longer calls than senior males. Thus, it is plausible that gibbon vocalizations provide receivers with information about singers' attributes. PMID:24367551

  17. Cues to androgens and quality in male gibbon songs.

    PubMed

    Barelli, Claudia; Mundry, Roger; Heistermann, Michael; Hammerschmidt, Kurt

    2013-01-01

    Animal vocal signals may provide information about senders and mediate important social interactions like sexual competition, territory maintenance and mate selection. Hence, it is important to understand whether vocal signals provide accurate information about animal attributes or status. Gibbons are non-human primates that produce loud, distinctive and melodious vocalizations resembling more those of birds than of other non-human primates. Wild gibbons are characterized by flexibility in social organization (i.e., pairs and multimale units) as well as in mating system (i.e., monogamy and polyandry). Such features make them a suitable model to investigate whether the physiology (hormonal status) and socio-demographic features find their correspondence in the structure of their songs. By combining male solo song recordings, endocrine outputs using non-invasive fecal androgen measures and behavioral observations, we studied 14 groups (10 pair-living, 4 multimale) of wild white-handed gibbons (Hylobates lar) residing at Khao Yai National Park, Thailand. We collected a total of 322 fecal samples and recorded 48 songs from 18 adult animals. Our results confirmed inter-individuality in male gibbon songs, and showed a clear correlation between androgen levels and song structures. Gibbons with higher androgen levels produced calls having higher pitch, and similarly adult individuals produced longer calls than senior males. Thus, it is plausible that gibbon vocalizations provide receivers with information about singers' attributes.

  18. Complement and immunoglobulins stimulate superoxide production by human leukocytes independently of phagocytosis.

    PubMed Central

    Goldstein, I M; Roos, D; Kaplan, H B; Weissmann, G

    1975-01-01

    Human peripheral blood polymorphonuclear leukocytes, when exposed to appropriate stimuli, generate significant amounts of superoxide anion (O-.2), a highly reactive molecule which is possibly involved in bacterial killing. Since the subcellular localization and mechanism of activation of O-.2 generating systems are unknown, we have investigated superoxide dismutase-inhibitable cytochrome c reduction (attributable to O-.2) by, and lysosomal enzyme release from, normal polymorphonuclear leukocytes and cells rendered incapable of ingesting particles by treatment with cytochalasin B. Neither phagocytosis nor lysosomal degranulation were prerequisites for enhanced O-.2 generation. Cytochalasin B-treated cells exposed to (a) serum-treated zymosan, a C3b receptor stimulus; (b) heat aggregated human IgG, an Fc receptor stimulus; and (c) the complement component, C5a, generated enhanced amounts of O-.2 in a time and concentration-dependent fashion. These cells also responded by releasing lysosomal enzymes, but there was no correlation between the ability of any immune reactant to provoke enzyme release and its ability to stimulate O-.2 generation. The three stimuli also enhanced O-.2 generation by normal (untreated) polymorphonuclear leukocytes, but only serum-treated zymosan and aggregated IgG were capable of provoking lysosomal enzyme release from normal cells. Untreated zymosan and native IgG neither stimulated O-.2 production nor provoked lysomal enzyme release. Since enhanced O-.2 production was stimulated by immune reactants in the absence of phagocytosis, the O-.2 generating system is very likely associated with the external plasma membrane of the polymorphonuclear leukocyte. Leukocyte membrane receptors for complement and immunoglobulins may therefore not only serve in particle recognition but also may initiate biochemical events which accompany phagocytosis and killing. PMID:171281

  19. NMO sera down-regulate AQP4 in human astrocyte and induce cytotoxicity independent of complement.

    PubMed

    Haruki, Hiroyo; Sano, Yasuteru; Shimizu, Fumitaka; Omoto, Masatoshi; Tasaki, Ayako; Oishi, Mariko; Koga, Michiaki; Saito, Kazuyuki; Takahashi, Toshiyuki; Nakada, Tsutomu; Kanda, Takashi

    2013-08-15

    Autoantibodies against astrocyte water channel aquaporin-4 (AQP4) are highly specific for neuromyelitis optica (NMO). However, the molecular mechanism of NMO still remains unclear. The purpose of this study was to identify the possible humoral mechanisms responsible for the occurrence of astrocytic damage. Human primary astrocytes (AST) were immortalized by retroviral vectors harboring temperature-sensitive SV40 T antigen gene and AQP4 cDNA (M23), designated as hAST-AQP4. The effects of NMO sera on the content and localization of AQP4, including cytotoxicity and astrocytic morphology, were evaluated. In addition, this study examined whether the amount and localization of AQP4 protein in astrocytes were influenced by direct contact with the immortalized human brain microvascular endothelial cell line, TY09. NMO sera alone induced cytotoxicity and addition of complement had a more harmful effect on hAST-AQP4. NMO sera also decreased AQP4 mRNA and protein. NMO sera alone up-regulated TNFα and IL-6 in astrocytes and co-incubation with anti-TNFα and anti-IL-6 neutralizing antibodies blocked both the cytotoxicity and reduction of AQP4 in astrocytes. In the experiment using the in vitro BBB models, AQP4 protein mainly localized at the astrocytic membrane after co-culture with TY09, in contact with TY09. The future elucidation of factors that up-regulate AQP4 in astrocytes presumably released by blood brain barrier forming endothelial cells and that block the production of inflammatory cytokines may therefore lead to the development of a novel therapeutic strategy.

  20. 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...

  1. Identification of Metabolites of Trenbolone Acetate in Androgenic Runoff from a Beef Feedlot

    PubMed Central

    Durhan, Elizabeth J.; Lambright, Christy S.; Makynen, Elizabeth A.; Lazorchak, James; Hartig, Phillip C.; Wilson, Vickie S.; Gray, L. Earl; Ankley, Gerald T.

    2006-01-01

    Little is known concerning the potential ecological effects of hormonally active substances associated with discharges from animal feeding operations. Trenbolone acetate is a synthetic anabolic steroid that is widely used in the United States to promote growth of beef cattle. Metabolites of trenbolone acetate include the stereoisomers 17α- and 17β-trenbolone, both of which are stable in animal wastes and are relatively potent androgens in fish and mammals. Our purpose in this study was to evaluate the occurrence of 17α- and 17β-trenbolone in a beef cattle feedlot discharge and in river water upstream and downstream from the discharge. In conjunction with that effort, we measured in vitro androgenic activity of the discharge using CV-1 cells that had been transiently cotransfected with human androgen receptor and reporter gene constructs. Samples were collected on nine different occasions during 2002 and 2003. Whole-water samples from the discharge caused a significant androgenic response in the CV-1 cells and contained detectable concentrations of 17α- and 17β-trenbolone. Further work is needed to ascertain the degree to which synthetic androgens such as trenbolone contribute to androgenic activity of feedlot discharges. PMID:16818248

  2. Inflammation and epithelial alterations in rat prostate: impact of the androgen to oestrogen ratio.

    PubMed

    Yatkin, Emrah; Bernoulli, Jenni; Talvitie, Eva-Maria; Santti, Risto

    2009-08-01

    Chronic non-bacterial prostatitis may offer new insights into the pathogenesis of human benign prostatic hyperplasia and prostate cancer and the strategies for their treatment and prevention. The potential significance of androgen replacement therapy in terms of the reversal of oestradiol (E(2))-induced inflammatory reaction was studied in the dorsolateral prostate (DLP) of the Noble rat. Castrated Noble rats were treated with E(2) and different doses of androgens [dihydrotestosterone (DHT) and testosterone (T)] to achieve an elevated concentration of E(2) and a wide range of the androgen-to-oestradiol ratios in serum. After the 3-week treatment, inflammatory changes in the DLP were classified and counted. Oestrogen receptor alpha (ER alpha), progesterone receptor (PR), fos-related antigen-2 (Fra2), Ki-67 and P63 were immunocytochemically stained. T, E(2) and prolactin concentrations in serum were measured and the relative weights of the seminal vesicles and pituitary glands and microscopic structures of the DLP and seminal vesicle ducts were determined. Hypoandrogenic doses of DHT (judged on the basis of seminal vesicle weight gain), dose-dependently increased the number of perivascular and stromal inflammatory infiltrates. T and DHT were anti-inflammatory at the doses which normalized or over stimulated the growth of the seminal vesicles. As signs of anti-oestrogenicity, androgens dose-dependently decreased the number and distribution of the ER alpha and PR-positive cells at proinflammatory concentrations. Anti-inflammatory concentrations were needed to reduce the expression of Fra2, E(2)-increased prolactin concentration in serum and pituitary weight. The androgen concentrations required to prevent proinflammatory and epithelial responses to E(2) in the presence of elevated E(2) concentrations may subject the accessory sex glands to more intense androgenic stimulation than is normal for the male. The androgen-resistant endpoints of oestrogen action (body weight

  3. Androgen receptor gene mutation, rearrangement, polymorphism.

    PubMed

    Eisermann, Kurtis; Wang, Dan; Jing, Yifeng; Pascal, Laura E; Wang, Zhou

    2013-09-01

    Genetic aberrations of the androgen receptor (AR) caused by mutations, rearrangements, and polymorphisms result in a mutant receptor that has varied functions compared to wild type AR. To date, over 1,000 mutations have been reported in the AR with most of these being associated with androgen insensitivity syndrome (AIS). While mutations of AR associated with prostate cancer occur less often in early stage localized disease, mutations in castration-resistant prostate cancer (CRPC) patients treated with anti-androgens occur more frequently with 10-30% of these patients having some form of mutation in the AR. Resistance to anti-androgen therapy usually results from gain-of-function mutations in the LBD such as is seen with bicalutamide and more recently with enzalutamide (MDV3100). Thus, it is crucial to investigate these new AR mutations arising from drug resistance to anti-androgens and other small molecule pharmacological agents.

  4. Hyperinsulinaemic androgen excess in adolescent girls.

    PubMed

    Ibáñez, Lourdes; Ong, Ken K; López-Bermejo, Abel; Dunger, David B; de Zegher, Francis

    2014-08-01

    Hyperinsulinaemic androgen excess is the most common cause of hirsutism, acne and menstrual irregularity in adolescent girls. Here, we propose that the disorder frequently originates from an absolute or relative excess of lipids in adipose tissue, and from associated changes in insulin sensitivity, gonadotropin secretion and ovarian androgen release. Girls from populations with genotypes attuned to nutritionally harsh conditions seem to be particularly vulnerable to the development of hyperinsulinaemic androgen excess in today's obesogenic environment. We propose that hirsutism, hyperandrogenaemia and menstrual irregularity (≥2 years after menarche) is used as a diagnostic triad for the disorder. No pharmacological therapy has been approved for girls with androgen excess; however, lifestyle intervention is essential to reduce adiposity. In girls without obesity who are not sexually active, insulin sensitization has more broadly normalizing effects than estradiol-progestogen combinations. The early recognition of girls at risk of developing hyperinsulinaemic androgen excess might enable prevention in childhood.

  5. 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

  6. DNA-binding dependent and independent functions of WT1 protein during human hematopoiesis

    SciTech Connect

    Svensson, Emelie; Eriksson, Helena; Gekas, Christos; Olofsson, Tor; Richter, Johan; Gullberg, Urban . E-mail: urban.gullberg@hematologi.lu.se

    2005-08-01

    The Wilms tumor gene 1 (WT1) encodes a zinc-finger-containing transcription factor highly expressed in immature hematopoietic progenitor cells. Overexpression and presence of somatic mutations in acute leukemia indicate a role for WT1 in the pathogenesis of leukemia. CD34{sup +} progenitor cells were transduced with one splice variant of human WT1 without the KTS insert in the zinc-finger domain, WT1(+/-), and with a deleted mutant of WT1 lacking the entire zinc-finger region, WT1(delZ), thus incapable of binding DNA. We show that inhibition of erythroid colony formation and differentiation is absolutely dependent on the DNA-binding zinc-finger domain of WT1. Unexpectedly, however, WT1(delZ) was equally effective as wild type protein in the reduction of myeloid clonogenic growth as well as in stimulation of myeloid differentiation, as judged by the expression of cell surface CD11b. Expression of neither WT1(+/-) nor WT1(delZ) upregulated mRNA for the cdk inhibitor p21{sup Waf1/Cip1} or p27{sup Kip1}. Our results demonstrate that WT1 affects proliferation and differentiation in erythroid and myeloid cells by different molecular mechanisms, and suggest that mutations affecting the zinc-finger domain of WT1 could interfere with normal differentiation in the pathogenesis of leukemia.

  7. Human interleukin-1-induced murine osteoclastogenesis is dependent on RANKL, but independent of TNF-alpha.

    PubMed

    Ma, Ting; Miyanishi, Keita; Suen, Andrew; Epstein, Noah J; Tomita, Tetsuya; Smith, R Lane; Goodman, Stuart B

    2004-05-01

    Although interleukin-1 (IL-1) has been implicated in the pathogenesis of inflammatory osteolysis, the means by which it recruits osteoclasts and promotes bone destruction are largely unknown. Recently, a cytokine-driven, stromal cell-free mouse osteoclastogenesis model was established. A combination of macrophage colony stimulating factor (M-CSF) and receptor activator of NFkappaB ligand (RANKL) was proven to be sufficient in inducing differentiation of bone marrow hematopoietic precursor cells to bone-resorbing osteoclasts in the absence of stromal cells or osteoblasts. This study utilizes this model to examine the impact of human IL-1beta on in vitro osteoclastogenesis of bone marrow progenitor cells. We found that osteoclast precursor cells failed to undergo osteoclastogenesis when treated with IL-1 alone. In contrast, IL-1 dramatically up-regulated osteoclastogenesis by 2.5- to 4-folds in the presence of RANKL and M-CSF. The effect can be significantly blocked by IL-1 receptor antagonist (p < 0.01). Tumor necrosis factor-alpha (TNF-alpha) was undetectable in the culture medium of differentiating osteoclasts induced by IL-1. Adding exogenous TNF-alpha neutralizing antibody had no influence on the IL-1-induced effect as well. These results show that in the absence of stromal cells, IL-1 exacerbates osteoclastogenesis by cooperating with RANKL and M-CSF, while TNF-alpha is not involved in this IL-1-stimulated osteoclast differentiation pathway.

  8. Glycoprotein Ic-IIa functions as an activation-independent fibronectin receptor on human platelets.

    PubMed

    Piotrowicz, R S; Orchekowski, R P; Nugent, D J; Yamada, K Y; Kunicki, T J

    1988-04-01

    Soluble fibronectin binds specifically to glycoprotein (GP) IIb-IIIa on thrombin-activated platelets, and this binding is not observed with platelets of patients with Glanzmann's thrombasthenia (GT) which lack GPIIb-IIIa. Here we report that GT platelets retain the ability to interact with fibronectin-coated surfaces. Adhesion to fibronectin does not require platelet activation and is inhibited by soluble fibronectin, antibodies specific for fibronectin, peptides containing the sequence Arg-Gly-Asp and polyclonal antibodies specific for band 3 of the chicken embryo fibroblast fibronectin receptor (anti-band 3). Using anti-band 3, we have purified a second fibronectin receptor from human platelets, a heterodimer composed of glycoproteins previously designated GPIc and GPIIa. The GPIc-IIa complex is found on both GT and normal platelets and appears to be identical to the GP138 kD-GP160 kD complex recently immunopurified by Giancotti et al. (1986. Exp. Cell Res. 163:47-62) and by Sonnenberg et al. (1987. J. Biol. Chem. 268:10376-10383). In this report, we provide the first evidence that GPIc-IIa actually mediates adhesion of platelets to fibronectin-coated surfaces. GPIc-IIa thus represents a second functional fibronectin receptor, distinct from GPIIb-IIIa, that is largely responsible for the adhesion of nonactivated platelets to fibronectin-coated surfaces.

  9. Bioanalytical LC-MS Method for the Quantification of Plasma Androgens and Androgen Glucuronides in Breast Cancer.

    PubMed

    Kalogera, Eleni; Pistos, Constantinos; Provatopoulou, Xeni; Christophi, Costas A; Zografos, George C; Stefanidou, Maria; Spiliopoulou, Chara; Athanaselis, Sotirios; Gounaris, Antonia

    2016-04-01

    The physiological and pathological development of the breast is strongly affected by the hormonal milieu consisting of steroid hormones. Mass spectrometry (MS) technologies of high sensitivity and specificity enable the quantification of androgens and consequently the characterization of the hormonal status. The aim of this study is the assessment of plasma androgens and androgen glucuronides, in the par excellence hormone-sensitive tissue of the breast, through the application of liquid chromatography-mass spectrometry (LC-MS). A simple and efficient fit-for-purpose method for the simultaneous identification and quantification of dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), androsterone glucuronide (ADTG) and androstane-3α, 17β-diol-17-glucuronide (3α-diol-17G) in human plasma was developed and validated. The presented method permits omission of derivatization, requires a single solid-phase extraction procedure and the chromatographic separation can be achieved on a single C18 analytical column, for all four analytes. The validated method was successfully applied for the analysis of 191 human plasma samples from postmenopausal women with benign breast disease (BBD), lobular neoplasia (LN), ductal carcinoma in situ and invasive ductal carcinoma (IDC). DHEAS plasma levels exhibited significant differences between LN, IDC and BBD patients (P < 0.05). Additionally, ADTG levels were significantly higher in patients with LN compared with those with BBD (P < 0.05). PMID:26762957

  10. Reduced glycosylation of human cell lines increases susceptibility to CD4-independent infection by human immunodeficiency virus type 2 (LAV-2/B).

    PubMed Central

    Talbot, S J; Weiss, R A; Schulz, T F

    1995-01-01

    The human immunodeficiency virus type 2 (HIV-2) strain LAV-2/B is able to infect a variety of human cell lines via a CD4-independent pathway. We have used the glycosylation inhibitors tunicamycin, swainsonine, and deoxymannojirimycin to further characterize this putative alternative receptor for HIV-2 (LAV-2/B). These antibiotics resulted in an increase (5- to 30-fold) in the susceptibility of a variety of CD4- human cell lines to infection by LAV-2/B (RD, HeLa, HT29, Rsb, Heb7a, Hos, and Daudi). Several nonprimate cell lines (mink Mv-1-lu, rabbit SIRC, hamster a23, mouse NIH 3T3, cat CCC, and rat HSN) remained resistant to infection by LAV-2/B after treatment with glycosylation inhibitors, suggesting that they do not express the HIV-2 CD4-independent receptor. Two of these nonprimate cell lines are readily infected by HIV-2 when they express CD4 (Mv-1-lu and CCC). Treatment of human cells with neuraminidase had no effect on subsequent infection by LAV-2/B, suggesting that the increase in susceptibility to infection of deglycosylated cells is not due to a change in the electrostatic charge of the cell surface. Treatment of RD CD4- cells and HeLa CD4+ cells with a variety of proteases resulted in a 75 to 90% decrease in infection by LAV-2/B when compared with untreated cells. Taken together, all these data suggest that HIV-2 can utilize a membrane glycoprotein other than CD4 to attach and fuse with a variety of human cells. PMID:7745686

  11. Mistic's membrane association and its assistance in overexpression of a human GPCR are independent processes

    PubMed Central

    Marino, Jacopo; Bordag, Natalie; Keller, Sandro; Zerbe, Oliver

    2015-01-01

    The interaction of the Bacillus subtilis protein Mistic with the bacterial membrane and its role in promoting the overexpression of other membrane proteins are still matters of debate. In this study, we aimed to determine whether individual helical fragments of Mistic are sufficient for its interaction with membranes in vivo and in vitro. To this end, fragments encompassing each of Mistic's helical segments and combinations of them were produced as GFP-fusions, and their cellular localization was studied in Escherichia coli. Furthermore, peptides corresponding to the four helical fragments were synthesized by solid-phase peptide synthesis, and their ability to acquire secondary structure in a variety of lipids and detergents was studied by circular dichroism spectroscopy. Both types of experiments demonstrate that the third helical fragment of Mistic interacts only with LDAO micelles but does not partition into lipid bilayers. Interestingly, the other three helices interact with membranes in vivo and in vitro. Nevertheless, all of these short sequences can replace full-length Mistic as N-terminal fusions to achieve overexpression of a human G-protein-coupled receptor in E. coli, although with different effects on quantity and quality of the protein produced. A bioinformatic analysis of the Mistic family expanded the number of homologs from 4 to 20, including proteins outside the genus Bacillus. This information allowed us to discover a highly conserved Shine-Dalgarno sequence in the operon mstX-yugO that is important for downstream translation of the potassium ion channel yugO. PMID:25297828

  12. In Vitro Androgen Bioassays as a Detection Method for Designer Androgens

    PubMed Central

    Cooper, Elliot R.; McGrath, Kristine C. Y.; Heather, Alison K.

    2013-01-01

    Androgens are the class of sex steroids responsible for male sexual characteristics, including increased muscle mass and decreased fat mass. Illicit use of androgen doping can be an attractive option for those looking to enhance sporting performance and/or physical appearance. The use of in vitro bioassays to detect androgens, especially designer or proandrogens, is becoming increasingly important in combating androgen doping associated with nutritional supplements. The nutritional sports supplement market has grown rapidly throughout the past decade. Many of these supplements contain androgens, designer androgens or proandrogens. Many designer or proandrogens cannot be detected by the standard highly-sensitive screening methods such as gas chromatography-mass spectrometry because their chemical structure is unknown. However, in vitro androgen bioassays can detect designer and proandrogens as these assays are not reliant on knowing the chemical structure but instead are based on androgen receptor activation. For these reasons, it may be advantageous to use routine androgen bioassay screening of nutraceutical samples to help curb the increasing problem of androgen doping. PMID:23389345

  13. MiR137 is an androgen regulated repressor of an extended network of transcriptional coregulators

    PubMed Central

    Whitchurch, Jonathan; McWilliam, Andrew; Ødum, Niels; Persson, Jenny L.; Heery, David M.; Gudas, Lorraine J.; Mongan, Nigel P.

    2015-01-01

    Androgens and the androgen receptor (AR) play crucial roles in male development and the pathogenesis and progression of prostate cancer (PCa). The AR functions as a ligand dependent transcription factor which recruits multiple enzymatically distinct epigenetic coregulators to facilitate transcriptional regulation in response to androgens. Over-expression of AR coregulators is implicated in cancer. We have shown that over-expression of KDM1A, an AR coregulator, contributes to PCa recurrence by promoting VEGFA expression. However the mechanism(s) whereby AR coregulators are increased in PCa remain poorly understood. In this study we show that the microRNA hsa-miR-137 (miR137) tumor suppressor regulates expression of an extended network of transcriptional coregulators including KDM1A/LSD1/AOF1, KDM2A/JHDM1A/FBXL11, KDM4A/JMJD2A, KDM5B JARID1B/PLU1, KDM7A/JHDM1D/PHF8, MED1/TRAP220/DRIP205 and NCoA2/SRC2/TIF2. We show that expression of miR137 is increased by androgen in LnCaP androgen PCa responsive cells and that the miR137 locus is epigenetically silenced in androgen LnCaP:C4-2 and PC3 independent PCa cells. In addition, we found that restoration of miR137 expression down-regulates expression of VEGFA, an AR target gene, which suggests a role of miR137 loss also in cancer angiogenesis. Finally we show functional inhibition of miR137 function enhanced androgen induction of PSA/KLK3 expression. Our data indicate that miR137 functions as an androgen regulated suppressor of androgen signaling by modulating expression of an extended network of transcriptional coregulators. Therefore, we propose that epigenetic silencing of miR137 is an important event in promoting androgen signaling during prostate carcinogenesis and progression. PMID:26461474

  14. Regulation of human epidermal stem cell proliferation and senescence requires polycomb- dependent and -independent functions of Cbx4.

    PubMed

    Luis, Nuno Miguel; Morey, Lluis; Mejetta, Stefania; Pascual, Gloria; Janich, Peggy; Kuebler, Bernd; Cozutto, Luca; Roma, Guglielmo; Nascimento, Elisabete; Frye, Michaela; Di Croce, Luciano; Benitah, Salvador Aznar

    2011-09-01

    Human epidermal stem cells transit from a slow cycling to an actively proliferating state to contribute to homeostasis. Both stem cell states differ in their cell cycle profiles but must remain guarded from differentiation and senescence. Here we show that Cbx4, a Polycomb Repressive Complex 1 (PRC1)-associated protein, maintains human epidermal stem cells as slow-cycling and undifferentiated, while protecting them from senescence. Interestingly, abrogating the polycomb activity of Cbx4 impairs its antisenescent function without affecting stem cell differentiation, indicating that differentiation and senescence are independent processes in human epidermis. Conversely, Cbx4 inhibits stem cell activation and differentiation through its SUMO ligase activity. Global transcriptome and chromatin occupancy analyses indicate that Cbx4 regulates modulators of epidermal homeostasis and represses factors such as Ezh2, Dnmt1, and Bmi1 to prevent the active stem cell state. Our results suggest that distinct Polycomb complexes balance epidermal stem cell dormancy and activation, while continually preventing senescence and differentiation. PMID:21885019

  15. TREK-1 Regulates Cytokine Secretion from Cultured Human Alveolar Epithelial Cells Independently of Cytoskeletal Rearrangements

    PubMed Central

    Schwingshackl, Andreas; Roan, Esra; Teng, Bin; Waters, Christopher M.

    2015-01-01

    Background TREK-1 deficient alveolar epithelial cells (AECs) secrete less IL-6, more MCP-1, and contain less F-actin. Whether these alterations in cytokine secretion and F-actin content are related remains unknown. We now hypothesized that cytokine secretion from TREK-1-deficient AECs was regulated by cytoskeletal rearrangements. Methods We determined F-actin and α-tubulin contents of control, TREK-1-deficient and TREK-1-overexpressing human A549 cells by confocal microscopy and western blotting, and measured IL-6 and MCP-1 levels using real-time PCR and ELISA. Results Cytochalasin D decreased the F-actin content of control cells. Jasplakinolide increased the F-actin content of TREK-1 deficient cells, similar to the effect of TREK-1 overexpression in control cells. Treatment of control and TREK-1 deficient cells with TNF-α, a strong stimulus for IL-6 and MCP-1 secretion, had no effect on F-actin structures. The combination of TNF-α+cytochalasin D or TNF-α+jasplakinolide had no additional effect on the F-actin content or architecture when compared to cytochalasin D or jasplakinolide alone. Although TREK-1 deficient AECs contained less F-actin at baseline, quantified biochemically, they contained more α-tubulin. Exposure to nocodazole disrupted α-tubulin filaments in control and TREK-1 deficient cells, but left the overall amount of α-tubulin unchanged. Although TNF-α had no effect on the F-actin or α-tubulin contents, it increased IL-6 and MCP-1 production and secretion from control and TREK-1 deficient cells. IL-6 and MCP-1 secretions from control and TREK-1 deficient cells after TNF-α+jasplakinolide or TNF-α+nocodazole treatment was similar to the effect of TNF-α alone. Interestingly, cytochalasin D decreased TNF-α-induced IL-6 but not MCP-1 secretion from control but not TREK-1 deficient cells. Conclusion Although cytochalasin D, jasplakinolide and nocodazole altered the F-actin and α-tubulin structures of control and TREK-1 deficient AEC, the

  16. Androgens and the aging male.

    PubMed

    Seidman, Stuart N

    2007-01-01

    In contrast to women, men do not experience a sudden cessation of gonadal function comparable to menopause. However, there is a progressive reduction in male hypothalamic-pituitary-gonadal (HPG) axis function: testosterone levels decline through both central (pituitary) and peripheral (testicular) mechanisms, and there is a loss of the circadian rhythm of testosterone secretion. The progressive decline in testosterone levels has been demonstrated in both cross-sectional and longitudinal studies, and overall at least 25% of men over age 70 meet laboratory criteria for hypogonadism (ie, testosterone deficiency). Such age-associated HPG hypofunctioning, which has been termed "andropause," is thought to be responsible for a variety of symptoms experienced by elderly men, including weakness, fatigue, reduced muscle and bone mass, impaired hematopoiesis, sexual dysfunction (including erectile dysfunction and loss of libido), and depression. Although, it has been difficult to establish correlations between these symptoms and plasma testosterone levels, there is some evidence that testosterone replacement leads to symptom relief, particularly with respect to muscle strength, bone mineral density, and erectile dysfunction. There is little evidence of a link between the HPG axis hypofunctioning and depressive illness, and exogenous androgens have not been consistently shown to have antidepressant activity. This article reviews the relationship between androgens, depression, and sexual function in aging men.

  17. Intracellular Distribution of Human T-Cell Leukemia Virus Type 1 Gag Proteins Is Independent of Interaction with Intracellular Membranes

    PubMed Central

    LeBlanc, Isabelle; Blot, Vincent; Bouchaert, Isabelle; Salamero, Jean; Goud, Bruno; Rosenberg, Arielle R.; Dokhélar, Marie-Christine

    2002-01-01

    Retrovirus Gag proteins are synthesized on free ribosomes, and are sufficient to govern the assembly and release of virus particles. Like type C retroviruses, human T-cell leukemia virus type 1 (HTLV-1) assembles and buds at the plasma membrane. After immunofluorescence staining, HTLV-1 Gag proteins appear as punctuated intracellular clusters, which suggests that they are associated either with intracellular membranes or with the plasma membrane. However, colocalization experiments using a panel of markers demonstrated that Gag proteins were not associated with the membranes involved in the secretory or endocytosis pathway. Small amounts of Gag proteins were detected at the plasma membrane and colocalized with the envelope glycoproteins. Moreover, Gag proteins were excluded from streptolysin-O permeabilized cells and in this respect behaved like cytoplasmic proteins. This suggests that the trafficking of HTLV-1 Gag proteins through the cytoplasm of the host cell is independent of any cell membrane system. PMID:11752179

  18. Human rhomboid family-1 suppresses oxygen-independent degradation of hypoxia-inducible factor-1α in breast cancer.

    PubMed

    Zhou, Zhuan; Liu, Fangfang; Zhang, Zhi-Song; Shu, Feifei; Zheng, Yangyang; Fu, Li; Li, Lu-Yuan

    2014-05-15

    Intermittent oxygen deficiency in cancers promotes prolonged inflammation, continuous angiogenesis, and increased drug resistance. Hypoxia-inducible factor-1 (HIF1) has a pivotal role in the regulation of cellular responses to oxygen deficiency. The α-subunit of HIF1 (HIF1α) is degraded in normoxia but stabilized in hypoxia. However, the molecular mechanism that controls oxygen-independent degradation of HIF1α has remained elusive. Human rhomboid family-1 (RHBDF1) is a member of a large family of nonprotease rhomboids whose function is basically unknown. We report here that RHBDF1 expression in breast cancer is highly elevated and is strongly correlated with escalated disease progression, metastasis, poor prognosis, and poor response to chemotherapy. We show that RHBDF1 interaction with the receptor of activated protein-C kinase-1 (RACK1) in breast cancer cells prevents RACK1-assisted, oxygen-independent HIF1α degradation. In addition, we show that the HIF1α-stabilizing activity of RHBDF1 diminishes when the phosphorylation of a tyrosine residue on the RHBDF1 molecule is inhibited. These findings are consistent with the view that RHBDF1 is a critical component of a molecular switch that regulates HIF1α stability in cancer cells in hypoxia and that RHBDF1 is of potential value as a new target for cancer treatment.

  19. Kaempferol inhibits angiogenesis and VEGF expression through both HIF dependent and independent pathways in human ovarian cancer cells.

    PubMed

    Luo, Haitao; Rankin, Gary O; Liu, Lingzhi; Daddysman, Matthew K; Jiang, Bing-Hua; Chen, Yi Charlie

    2009-01-01

    Ovarian cancer is 1 of the most significant malignancies in the Western world, and the antiangiogenesis strategy has been postulated for prevention and treatment of ovarian cancers. Kaempferol is a natural flavonoid present in many fruits and vegetables. The antiangiogenesis potential of kaempferol and its underlying mechanisms were investigated in two ovarian cancer cell lines, OVCAR-3 and A2780/CP70. Kaempferol mildly inhibits cell viability but significantly reduces VEGF gene expression at mRNA and protein levels in both ovarian cancer cell lines. In chorioallantoic membranes of chicken embryos, kaempferol significantly inhibits OVCAR-3-induced angiogenesis and tumor growth. HIF-1alpha, a regulator of VEGF, is downregulated by kaempferol treatment in both ovarian cancer cell lines. Kaempferol also represses AKT phosphorylation dose dependently at 5 to 20 muM concentrations. ESRRA is a HIF-independent VEGF regulator, and it is also downregulated by kaempferol in a dose-dependent manner. Overall, this study demonstrated that kaempferol is low in cytotoxicity but inhibits angiogenesis and VEGF expression in human ovarian cancer cells through both HIF-dependent (Akt/HIF) and HIF-independent (ESRRA) pathways and deserves further studies for possible application in angio prevention and treatment of ovarian cancers.

  20. Isogambogenic acid induces apoptosis-independent autophagic cell death in human non-small-cell lung carcinoma cells.

    PubMed

    Yang, Jianhong; Zhou, Yongzhao; Cheng, Xia; Fan, Yi; He, Shichao; Li, Shucai; Ye, Haoyu; Xie, Caifeng; Wu, Wenshuang; Li, Chunyan; Pei, Heying; Li, Luyuan; Wei, Zhe; Peng, Aihua; Wei, Yuquan; Li, Weimin; Chen, Lijuan

    2015-01-09

    To overcome drug resistance caused by apoptosis deficiency in patients with non-small cell lung carcinoma (NSCLC), there is a need to identify other means of triggering apoptosis-independent cancer cell death. We are the first to report that isogambogenic acid (iso-GNA) can induce apoptosis-independent autophagic cell death in human NSCLC cells. Several features of the iso-GNA-treated NSCLC cells indicated that iso-GNA induced autophagic cell death. First, there was no evidence of apoptosis or cleaved caspase 3 accumulation and activation. Second, iso-GNA treatment induced the formation of autophagic vacuoles, increased LC3 conversion, caused the appearance of autophagosomes and increased the expression of autophagy-related proteins. These findings provide evidence that iso-GNA induces autophagy in NSCLC cells. Third, iso-GNA-induced cell death was inhibited by autophagic inhibitors or by selective ablation of Atg7 and Beclin 1 genes. Furthermore, the mTOR inhibitor rapamycin increased iso-GNA-induced cell death by enhancing autophagy. Finally, a xenograft model provided additional evidence that iso-GNA exhibited anticancer effect through inducing autophagy-dependent cell death in NSCLC cells. Taken together, our results demonstrated that iso-GNA exhibited an anticancer effect by inducing autophagy-dependent cell death in NSCLC cells, which may be an effective chemotherapeutic agent that can be used against NSCLC in a clinical setting.

  1. Isogambogenic acid induces apoptosis-independent autophagic cell death in human non-small-cell lung carcinoma cells

    PubMed Central

    Yang, Jianhong; Zhou, Yongzhao; Cheng, Xia; Fan, Yi; He, Shichao; Li, Shucai; Ye, Haoyu; Xie, Caifeng; Wu, Wenshuang; Li, Chunyan; Pei, Heying; Li, Luyuan; Wei, Zhe; Peng, Aihua; Wei, Yuquan; Li, Weimin; Chen, Lijuan

    2015-01-01

    To overcome drug resistance caused by apoptosis deficiency in patients with non-small cell lung carcinoma (NSCLC), there is a need to identify other means of triggering apoptosis-independent cancer cell death. We are the first to report that isogambogenic acid (iso-GNA) can induce apoptosis-independent autophagic cell death in human NSCLC cells. Several features of the iso-GNA-treated NSCLC cells indicated that iso-GNA induced autophagic cell death. First, there was no evidence of apoptosis or cleaved caspase 3 accumulation and activation. Second, iso-GNA treatment induced the formation of autophagic vacuoles, increased LC3 conversion, caused the appearance of autophagosomes and increased the expression of autophagy-related proteins. These findings provide evidence that iso-GNA induces autophagy in NSCLC cells. Third, iso-GNA-induced cell death was inhibited by autophagic inhibitors or by selective ablation of Atg7 and Beclin 1 genes. Furthermore, the mTOR inhibitor rapamycin increased iso-GNA-induced cell death by enhancing autophagy. Finally, a xenograft model provided additional evidence that iso-GNA exhibited anticancer effect through inducing autophagy-dependent cell death in NSCLC cells. Taken together, our results demonstrated that iso-GNA exhibited an anticancer effect by inducing autophagy-dependent cell death in NSCLC cells, which may be an effective chemotherapeutic agent that can be used against NSCLC in a clinical setting. PMID:25571970

  2. Trehalose, sucrose and raffinose are novel activators of autophagy in human keratinocytes through an mTOR-independent pathway

    PubMed Central

    Chen, Xu; Li, Min; Li, Li; Xu, Song; Huang, Dan; Ju, Mei; Huang, Ju; Chen, Kun; Gu, Heng

    2016-01-01

    Trehalose is a natural disaccharide that is found in a diverse range of organisms but not in mammals. Autophagy is a process which mediates the sequestration, lysosomal delivery and degradation of proteins and organelles. Studies have shown that trehalose exerts beneficial effects through inducing autophagy in mammalian cells. However, whether trehalose or other saccharides can activate autophagy in keratinocytes is unknown. Here, we found that trehalose treatment increased the LC3-I to LC3-II conversion, acridine orange-stained vacuoles and GFP-LC3B (LC3B protein tagged with green fluorescent protein) puncta in the HaCaT human keratinocyte cell line, indicating autophagy induction. Trehalose-induced autophagy was also observed in primary keratinocytes and the A431 epidermal cancer cell line. mTOR signalling was not affected by trehalose treatment, suggesting that trehalose induced autophagy through an mTOR-independent pathway. mTOR-independent autophagy induction was also observed in HaCaT and HeLa cells treated with sucrose or raffinose but not in glucose, maltose or sorbitol treated HaCaT cells, indicating that autophagy induction was not a general property of saccharides. Finally, although trehalose treatment had an inhibitory effect on cell proliferation, it had a cytoprotective effect on cells exposed to UVB radiation. Our study provides new insight into the saccharide-mediated regulation of autophagy in keratinocytes. PMID:27328819

  3. UL84-independent replication of human cytomegalovirus strains conferred by a single codon change in UL122.

    PubMed

    Spector, David J

    2015-02-01

    The UL84 gene of human cytomegalovirus (HCMV) is thought to be involved in the initiation of viral DNA replication, and is essential for replication of strains AD169 and Towne. Hence, discovery that strain TB40-BAC4 is viable in the absence of UL84 presented an enigma requiring an explanation. Data reported here show that strain TR also tolerated loss of UL84, whereas strains FIX, Merlin, Ph, and Toledo did not. UL84-independent growth required the viral replication origin. The genetic locus in TB40 that controls UL84 dependence was mapped to codon 388 of the UL122 gene, which encodes the immediate early 2 (IE2) 86kD protein. Introduction of this TB40-BAC4 variant (H388D) into FIX and Toledo clones converted these strains to UL84 independence. These results provide genetic evidence in virus-infected cells that supports the hypothesis that UL122 participates in the initiation of viral DNA replication by a mechanism involving transcription-mediated activation of the origin.

  4. Trehalose, sucrose and raffinose are novel activators of autophagy in human keratinocytes through an mTOR-independent pathway.

    PubMed

    Chen, Xu; Li, Min; Li, Li; Xu, Song; Huang, Dan; Ju, Mei; Huang, Ju; Chen, Kun; Gu, Heng

    2016-01-01

    Trehalose is a natural disaccharide that is found in a diverse range of organisms but not in mammals. Autophagy is a process which mediates the sequestration, lysosomal delivery and degradation of proteins and organelles. Studies have shown that trehalose exerts beneficial effects through inducing autophagy in mammalian cells. However, whether trehalose or other saccharides can activate autophagy in keratinocytes is unknown. Here, we found that trehalose treatment increased the LC3-I to LC3-II conversion, acridine orange-stained vacuoles and GFP-LC3B (LC3B protein tagged with green fluorescent protein) puncta in the HaCaT human keratinocyte cell line, indicating autophagy induction. Trehalose-induced autophagy was also observed in primary keratinocytes and the A431 epidermal cancer cell line. mTOR signalling was not affected by trehalose treatment, suggesting that trehalose induced autophagy through an mTOR-independent pathway. mTOR-independent autophagy induction was also observed in HaCaT and HeLa cells treated with sucrose or raffinose but not in glucose, maltose or sorbitol treated HaCaT cells, indicating that autophagy induction was not a general property of saccharides. Finally, although trehalose treatment had an inhibitory effect on cell proliferation, it had a cytoprotective effect on cells exposed to UVB radiation. Our study provides new insight into the saccharide-mediated regulation of autophagy in keratinocytes. PMID:27328819

  5. Structural characteristics of anabolic androgenic steroids contributing to binding to the androgen receptor and to their anabolic and androgenic activities. Applied modifications in the steroidal structure.

    PubMed

    Fragkaki, A G; Angelis, Y S; Koupparis, M; Tsantili-Kakoulidou, A; Kokotos, G; Georgakopoulos, C

    2009-02-01

    Anabolic androgenic steroids (AAS) are synthetic derivatives of testosterone introduced for therapeutic purposes providing enhanced anabolic potency with reduced androgenic effects. Androgens mediate their action through their binding to the androgen receptor (AR) which is mainly expressed in androgen target tissues, such as the prostate, skeletal muscle, liver and central nervous system. This paper reviews some of the wide spectrum of testosterone and synthetic AAS structure modifications related to the intended enhancement in anabolic activity. The structural features of steroids necessary for effective binding to the AR and those which contribute to the stipulation of the androgenic and anabolic activities are also presented.

  6. Biochemical and physiological aspects of endogenous androgens.

    PubMed

    Kicman, Andrew T

    2010-01-01

    This review attempts to give a synopsis of the major aspects concerning the biochemistry of endogenous androgens, supplemented with several facets of physiology, particularly with respect to testosterone. Testosterone continues to be the most common adverse finding declared by World Anti-Doping Agency accredited laboratories, such samples having an augmented testosterone to epitestosterone ratio. Knowledge regarding the precursors and metabolism of endogenous testosterone is therefore fundamental to understanding many of the issues concerning doping with testosterone and its prohormones, including the detection of their administration. Further, adverse findings for nandrolone are frequent, but this steroid and 19-norandrostenedione are also produced endogenously, an appealing hypothesis being that they are minor by-products of the aromatization of androgens. At sports tribunals pertaining to adverse analytical findings of natural androgen administration, experts often raise issues that concern some aspect of steroid biochemistry and physiology. Salient topics included within this review are the origins and interconversion of endogenous androgens, the biosynthesis of testosterone and epitestosterone, the mechanism of aromatization, the molecular biology of the androgen receptor, the hypothalamic-pituitary-testicular axis, disturbances to this axis by anabolic steroid administration, the transport (binding) of androgens in blood, and briefly the metabolism and excretion of androgens.

  7. Neuropeptide Y inhibits ciliary beat frequency in human ciliated cells via nPKC, independently of PKA.

    PubMed

    Wong, L B; Park, C L; Yeates, D B

    1998-08-01

    The intracellular mechanisms whereby the inhibitory neurotransmitter neuropeptide Y (NPY) decreases ciliary beat frequency (CBF) were investigated in cultured human tracheal and bronchial ciliated cells. CBF was measured by nonstationary analysis laser light scattering. NPY at 1 and 10 microM decreased CBF from a baseline of 6.7 +/- 0.5 (n = 12) to 6.1 +/- 0.5 (P < 0.05) and 5.8 +/- 0.4 (P < 0.01) Hz, respectively. Prior application of PYX-1, an NPY antagonist, prevented the decreases of CBF induced by both doses of NPY. Two broad protein kinase C (PKC) kinase inhibitors, staurosporine and calphostin C, also abolished the NPY-induced decrease in CBF. The NPY-induced decrease in CBF was abolished by GF 109203X, a novel PKC (nPKC) isoform inhibitor, whereas this decrease in CBF was not attenuated by Gö-6976, a specific inhibitor of conventional PKC isoforms. Because pretreatment with NPY did not block the stimulation of CBF by forskolin and pretreatment with forskolin did not abolish the NPY-induced inhibition of CBF, this NPY receptor-mediated signal transduction mechanism appears to be independent of the adenylate cyclase-protein kinase A (PKA) pathway. Inhibition of Ca2+-ATPase by thapsigargin also prevented the suppression of CBF induced by subsequent application of NPY. These novel data indicate that, in cultured human epithelia, NPY decreases CBF below its basal level via the activation of an nPKC isoform and Ca2+-ATPase, independent of the activity of PKA. This is consistent with the proposition that NPY is an autonomic efferent inhibitory neurotransmitter regulating mucociliary transport. PMID:9688598

  8. Independent [Ca2+]i increases and cell proliferation induced by the carcinogen safrole in human oral cancer cells.

    PubMed

    Huang, Jong-Khing; Huang, Chun-Jen; Chen, Wei-Chuan; Liu, Shiuh-Inn; Hsu, Shu-Shong; Chang, Hong-Tai; Tseng, Li-Ling; Chou, Chiang-Ting; Chang, Chih-Hung; Jan, Chung-Ren

    2005-07-01

    The effect of the carcinogen safrole on intracellular Ca2+ movement and cell proliferation has not been explored previously. The present study examined whether safrole could alter Ca2+ handling and growth in human oral cancer OC2 cells. Cytosolic free Ca2+ levels ([Ca2+]i) in populations of cells were measured using fura-2 as a fluorescent Ca2+ probe. Safrole at a concentration of 325 microM started to increase [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced by 40% by removing extracellular Ca2+, and was decreased by 39% by nifedipine but not by verapamil or diltiazem. In Ca2+-free medium, after pretreatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) barely induced a [Ca2+]i rise; in contrast, addition of safrole after thapsigargin treatment induced a small [Ca2+]i rise. Neither inhibition of phospholipase C with 2 microM U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 1 microM safrole did not alter cell proliferation, but incubation with 10-1000 microM safrole increased cell proliferation by 60+/-10%. This increase was not reversed by pre-chelating Ca2+ with 10 microM of the Ca2+ chelator BAPTA. Collectively, the data suggest that in human oral cancer cells, safrole induced a [Ca2+]i rise by causing release of stored Ca2+ from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion and by inducing Ca2+ influx via nifedipine-sensitive Ca2+ entry. Furthermore, safrole can enhance cell growth in a Ca2+-independent manner.

  9. Augmentation of virus secretion by the human immunodeficiency virus type 1 Vpu protein is cell type independent and occurs in cultured human primary macrophages and lymphocytes.

    PubMed Central

    Schubert, U; Clouse, K A; Strebel, K

    1995-01-01

    The human immunodeficiency virus type 1-specific Vpu protein is a small integral membrane phosphoprotein that induces degradation of the virus receptor CD4 in the endoplasmic reticulum and, independently, increases the release of progeny virions from infected cells. To address the importance of Vpu for virus replication in primary human cells such as peripheral blood mononuclear cells (PBMC) and monocyte-derived macrophages (MDM), we used three different sets of monocyte-tropic molecular clones of human immunodeficiency virus type 1: a primary isolate, AD8+, and two chimeric variants of the T-cell-tropic isolate NL4-3 carrying the env determinants of either AD8+ or SF162 monocyte-tropic primary isolates. Isogenic variants of these chimeric viruses were constructed to express either wild-type Vpu or various mutants of Vpu. The effects of these mutations in the vpu gene on virus particle secretion from infected MDM or PBMC were assessed by determination of the release of virion-associated reverse transcriptase into culture supernatants, Western blot (immunoblot) analysis of pelleted virions, and steady-state or pulse-chase metabolic labeling. Wild-type Vpu increased virus release four- to sixfold in MDM and two- to threefold in PBMC, while nonphosphorylated Vpu and a C-terminal truncation mutant of Vpu were partially active on virus release in primary cells. These results demonstrate that Vpu regulates virus release in primary lymphocyte and macrophage cultures in a similar manner and to a similar extent to those previously observed in HeLa cells or CD4+ T-cell lines. Thus, our findings provide evidence that Vpu functions in a variety of human cells, both primary cells and continuous cell lines, and mutations in Vpu affect its biological activity independent of the cell type and virus isolate used. PMID:7494279

  10. 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

  11. 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

  12. Preliminary investigations into triazole derived androgen receptor antagonists.

    PubMed

    Altimari, Jarrad M; Niranjan, Birunthi; Risbridger, Gail P; Schweiker, Stephanie S; Lohning, Anna E; Henderson, Luke C

    2014-05-01

    A range of 1,4-substituted-1,2,3-N-phenyltriazoles were synthesized and evaluated as non-steroidal androgen receptor (AR) antagonists. The motivation for this study was to replace the N-phenyl amide portion of small molecule antiandrogens with a 1,2,3-triazole and determine effects, if any, on biological activity. The synthetic methodology presented herein is robust, high yielding and extremely rapid. Using this methodology a series of 17 N-aryl triazoles were synthesized from commercially available starting materials in less than 3h. After preliminary biological screening at 20 and 40 μM, the most promising three compounds were found to display IC50 values of 40-50 μM against androgen dependent (LNCaP) cells and serve as a starting point for further structure-activity investigations. All compounds in this work were the focus of an in silico study to dock the compounds into the human androgen receptor ligand binding domain (hARLBD) and compare their predicted binding affinity with known antiandrogens. A comparison of receptor-ligand interactions for the wild type and T877A mutant AR revealed two novel polar interactions. One with Q738 of the wild type site and the second with the mutated A877 residue.

  13. Steroidogenesis inhibitors alter but do not eliminate androgen synthesis mechanisms during progression to castration-resistance in LNCaP prostate xenografts.

    PubMed

    Locke, Jennifer A; Nelson, Colleen C; Adomat, Hans H; Hendy, Stephen C; Gleave, Martin E; Guns, Emma S Tomlinson

    2009-07-01

    In castration-resistant prostate cancer (CRPC) many androgen-regulated genes become re-expressed and tissue androgen levels increase despite low serum levels. We and others have recently reported that CRPC tumor cells can de novo synthesize androgens from adrenal steroid precursors or cholesterol and that high levels of progesterone exist in LNCaP tumors after castration serving perhaps as an intermediate in androgen synthesis. Herein, we compare androgen synthesis from [(3)H-progesterone] in the presence of specific steroidogenesis inhibitors and anti-androgens in steroid starved LNCaP cells and CRPC tumors. Similarly, we compare steroid profiles in LNCaP tumors at different stages of CRPC progression. Steroidogenesis inhibitors targeting CYP17A1 and SRD5A2 significantly altered but did not eliminate androgen synthesis from progesterone in steroid starved LNCaP cells and CRPC tumors. Upon exposure to inhibitors of steroidogenesis prostate cancer cells adapt gradually during CRPC progression to synthesize DHT in a compensatory manner through alternative feed-forward mechanisms. Furthermore, tumors obtained immediately after castration are significantly less efficient at metabolizing progesterone ( approximately 36%) and produce a different steroid profile to CRPC tumors. Optimal targeting of the androgen axis may be most effective when tumors are least efficient at synthesizing androgens. Confirmatory studies in humans are required to validate these findings.

  14. Selective androgen receptor modulators: in pursuit of tissue-selective androgens.

    PubMed

    Omwancha, Josephat; Brown, Terry R

    2006-10-01

    The androgen receptor mediates the androgenic and anabolic activity of the endogenous steroids testosterone and 5alpha-dihydrotestosterone. Current knowledge of the androgen receptor protein structure, and the molecular mechanisms surrounding the binding properties and activities of agonists and antagonists has led to the design and development of novel nonsteroidal ligands with selected tissue-specific androgen receptor agonist and antagonist activities. The activity of these compounds, termed selective androgen receptor modulators (SARMs), is directed toward the maintenance or enhancement of anabolic effects on bone and muscle with minimal androgenic effects on prostate growth. SARMs are of potential therapeutic value in the treatment of male hypogonadism, osteoporosis, frailty and muscle wasting, burn injury and would healing, anemia, mood and depression, benign prostatic hyperplasia and prostate cancer.

  15. Sprouty 2 protein, but not Sprouty 4, is an independent prognostic biomarker for human epithelial ovarian cancer.

    PubMed

    Masoumi-Moghaddam, Samar; Amini, Afshin; Wei, Ai-Qun; Robertson, Gregory; Morris, David L

    2015-08-01

    Sprouty proteins are evolutionary-conserved modulators of receptor tyrosine kinase signaling, deregulation of which has been implicated in the pathophysiology of cancer. In the present study, the expression status of Spry2 and Spry4 proteins and its clinical relevance in human epithelial ovarian cancer (EOC) were investigated retrospectively. We examined the immunohistochemical expression of Spry2 and Spry4 in matched tumor and normal tissue samples from 99 patients. The expression of ERK, p-ERK, Ki67, fibroblast growth factor-2, vascular endothelial growth factor and interleukin-6 and their correlation with Sprouty homologs were also evaluated. Moreover, the correlation between Spry2 and Spry4 and the clinicopathological characteristics were analyzed along with their predictive value for overall survival (OS) and disease-free survival (DFS). Our data indicated significant downregulation of Spry2 and Spry4 in tumor tissues (p < 0.0001). A significant inverse correlation was evident between Spry2 and p-ERK/ERK (p = 0.048), Ki67 (p = 0.011), disease stage (p = 0.013), tumor grade (p = 0.003), recurrence (p < 0.001) and post-treatment ascites (p = 0.001), individually. It was found that Spry2 low-expressing patients had significantly poorer OS (p = 0.002) and DFS (p = 0.004) than those with high expression of Spry2. Multivariate analysis showed that high Spry2 (p = 0.018), low stage (p = 0.049) and no residual tumor (p =0.006) were independent prognostic factors for a better OS. With regard to DFS, high Spry2 (p = 0.044) and low stage (p = 0.046) remained as independent predictors. In conclusion, we report for the first time significant downregulation of Spry2 and Spry4 proteins in human EOC. Spry2 expression was revealed to significantly impact tumor behavior with predictive value as an independent prognostic factor for survival and recurrence.

  16. Prostate specific antigen gene expression in androgen insensitive prostate carcinoma subculture cell line.

    PubMed

    Tsui, Ke-Hung; Feng, Tsui-Hsia; Chung, Li-Chuan; Chao, Chun-Hsiang; Chang, Phei-Lang; Juang, Horng-Heng

    2008-01-01

    A novel prostate cancer cell line (PC-J) was isolated from an androgen independent non-prostate specific antigen (non-PSA) producing carcinoma cell line. The homologous correlation between PC-J and PC-3 was determined by short tandem repeat analysis. The PSA promoter activity was detected by transient expression assay in the PC-J and LNCaP cells but not in androgen insensitive PC-3 cells. When the PC-J cells were cotransfected with androgen receptor, androgen receptor coactivators and PSA reporter vector cells, the reporter assays indicated that nuclear receptor coactivator 4 (NCOA4) but not androgen receptor activator 24 (ARA24) increased the sensitivity and maximum stimulation of dihydrotestosterone (DHT)-inducing PSA promoter activity. The RT-PCR assays revealed that the expression of several tumor markers, including interleukin-6, prostate stem cell antigen (PSCA), prostate epithelium-specific Ets transcription factor (PDEF) and matriptase, was lower in the PC-J cells than in the PC-3 cells. This cell model elucidated the regulation of PSA expression and enabled comparison of the gene profile at different stages of metastasis in prostatic carcinoma.

  17. The androgen receptor gene mutations database.

    PubMed

    Patterson, M N; Hughes, I A; Gottlieb, B; Pinsky, L

    1994-09-01

    The androgen receptor gene mutations database is a comprehensive listing of mutations published in journals and meetings proceedings. The majority of mutations are point mutations identified in patients with androgen insensitivity syndrome. Information is included regarding the phenotype, the nature and location of the mutations, as well as the effects of the mutations on the androgen binding activity of the receptor. The current version of the database contains 149 entries, of which 114 are unique mutations. The database is available from EMBL (NetServ@EMBL-Heidelberg.DE) or as a Macintosh Filemaker file (mc33001@musica.mcgill.ca).

  18. Infection of human and non-human cells by a highly fusogenic primary CD4-independent HIV-1 isolate with a truncated envelope cytoplasmic tail

    SciTech Connect

    Saha, Kunal . E-mail: sahak@pediatrics.ohio-state.edu; Yan Hui; Nelson, Julie A.E.; Zerhouni-Layachi, Bouchra

    2005-06-20

    Truncation of the envelope cytoplasmic tail has enabled FIV, SIV, and some laboratory HIV-1 strains to acquire broader cellular tropism and enhanced fusogenicity. Here we have characterized a primary CD4-independent HIV-1 isolate (92UG046-T8) with a truncated cytoplasmic tail that was able to infect and induce syncytia in primary lymphocytes from human, chimpanzee, and monkey, as well as CD4-negative cell lines from human and monkey. Increased syncytia were also noticeable with 293 cells expressing the cloned envelope from the 92UG046-T8 isolate suggesting envelope-mediated cellular fusion. Except pooled serum from HIV-1-infected individuals, monoclonal anti-envelope antibodies or antibodies/antagonists against CD4, CXCR4, and CCR5 were not able to prevent infection by the 92UG046-T8 isolate. This is the first report showing a primary HIV-1 variant with truncated cytoplasmic tail which is highly fusogenic and can infect a broad range of cells from human and non-human origins. In vivo evolution of similar HIV-1 mutants may have important implications in AIDS pathogenesis.

  19. Expanding the therapeutic use of androgens via selective androgen receptor modulators (SARMs).

    PubMed

    Gao, Wenqing; Dalton, James T

    2007-03-01

    Selective androgen receptor modulators (SARMs) are a novel class of androgen receptor (AR) ligands that might change the future of androgen therapy dramatically. With improved pharmacokinetic characteristics and tissue-selective pharmacological activities, SARMs are expected to greatly extend the clinical applications of androgens to osteoporosis, muscle wasting, male contraception and diseases of the prostate. Mechanistic studies with currently available SARMs will help to define the contributions of differential tissue distribution, tissue-specific expression of 5alpha-reductase, ligand-specific regulation of gene expression and AR interactions with tissue-specific coactivators to their observed tissue selectivity, and lead to even greater expansion of selective anabolic therapies.

  20. Phosphatase-1 and -2A inhibition modulates apoptosis in human osteoarthritis chondrocytes independently of nitric oxide production

    PubMed Central

    Lopez-Armada, M; Carames, B; Cillero-Pastor, B; Lires-Dean, M; Maneiro, E; Fuentes, I; Ruiz, C; Galdo, F; Blanco, F

    2005-01-01

    Methods: Human OA chondrocytes were isolated from cartilage obtained from the femoral heads of patients undergoing joint replacement surgery. Cell viability was evaluated by MTT assay. Apoptosis was quantified by ELISA, which measures DNA fragmentation. Nitric oxide (NO) production was evaluated by the Greiss method, and inducible nitric oxide synthase (iNOS) protein synthesis was studied by western blotting. Results: Inhibition of PP1/2A by the specific inhibitor okadaic acid (OKA) dose and time dependently caused a reduction of cell viability (OKA at 50 nmol/l: a reduction to 60% and 43% at 48 and 72 hours, respectively). Genomic DNA from chondrocytes treated with OKA at 50 and 100 nmol/l for 48 hours displayed increased internucleosomal DNA fragmentation by 11 and 13 fields, respectively. Light microscopy and DAPI studies showed that OKA induced DNA condensation and fragmentation, typical of death by apoptosis. The caspase inhibitors Z-VAD-FMK and Z-DEVD-FMK increased cell viability, reduced by OKA at 50 nmol/l to 87% and 73%, respectively. OKA did not increase iNOS protein synthesis or NO production. Conclusion: PP1/2A modulate apoptosis in human OA chondrocytes; this is independent of NO production but dependent on caspases. PMID:15958763

  1. Human rhinovirus 14 enters rhabdomyosarcoma cells expressing icam-1 by a clathrin-, caveolin-, and flotillin-independent pathway.

    PubMed

    Khan, Abdul Ghafoor; Pickl-Herk, Angela; Gajdzik, Leszek; Marlovits, Thomas C; Fuchs, Renate; Blaas, Dieter

    2010-04-01

    Intercellular adhesion molecule 1 (ICAM-1) mediates binding and entry of major group human rhinoviruses (HRVs). Whereas the entry pathway of minor group HRVs has been studied in detail and is comparatively well understood, the pathway taken by major group HRVs is largely unknown. Use of immunofluorescence microscopy, colocalization with specific endocytic markers, dominant negative mutants, and pharmacological inhibitors allowed us to demonstrate that the major group virus HRV14 enters rhabdomyosarcoma cells transfected to express human ICAM-1 in a clathrin-, caveolin-, and flotillin-independent manner. Electron microscopy revealed that many virions accumulated in long tubular structures, easily distinguishable from clathrin-coated pits and caveolae. Virus entry was strongly sensitive to the Na(+)/H(+) ion exchange inhibitor amiloride and moderately sensitive to cytochalasin D. Thus, cellular uptake of HRV14 occurs via a pathway exhibiting some, but not all, characteristics of macropinocytosis and is similar to that recently described for adenovirus 3 entry via alpha(v) integrin/CD46 in HeLa cells.

  2. Human Rhinovirus 14 Enters Rhabdomyosarcoma Cells Expressing ICAM-1 by a Clathrin-, Caveolin-, and Flotillin-Independent Pathway ▿

    PubMed Central

    Khan, Abdul Ghafoor; Pickl-Herk, Angela; Gajdzik, Leszek; Marlovits, Thomas C.; Fuchs, Renate; Blaas, Dieter

    2010-01-01

    Intercellular adhesion molecule 1 (ICAM-1) mediates binding and entry of major group human rhinoviruses (HRVs). Whereas the entry pathway of minor group HRVs has been studied in detail and is comparatively well understood, the pathway taken by major group HRVs is largely unknown. Use of immunofluorescence microscopy, colocalization with specific endocytic markers, dominant negative mutants, and pharmacological inhibitors allowed us to demonstrate that the major group virus HRV14 enters rhabdomyosarcoma cells transfected to express human ICAM-1 in a clathrin-, caveolin-, and flotillin-independent manner. Electron microscopy revealed that many virions accumulated in long tubular structures, easily distinguishable from clathrin-coated pits and caveolae. Virus entry was strongly sensitive to the Na+/H+ ion exchange inhibitor amiloride and moderately sensitive to cytochalasin D. Thus, cellular uptake of HRV14 occurs via a pathway exhibiting some, but not all, characteristics of macropinocytosis and is similar to that recently described for adenovirus 3 entry via αv integrin/CD46 in HeLa cells. PMID:20130060

  3. Extracting the inclination angle of nerve fibers within the human brain with 3D-PLI independent of system properties

    NASA Astrophysics Data System (ADS)

    Reckfort, Julia; Wiese, Hendrik; Dohmen, Melanie; Grässel, David; Pietrzyk, Uwe; Zilles, Karl; Amunts, Katrin; Axer, Markus

    2013-09-01

    The neuroimaging technique 3D-polarized light imaging (3D-PLI) has opened up new avenues to study the complex nerve fiber architecture of the human brain at sub-millimeter spatial resolution. This polarimetry technique is applicable to histological sections of postmortem brains utilizing the birefringence of nerve fibers caused by the regular arrangement of lipids and proteins in the myelin sheaths surrounding axons. 3D-PLI provides a three-dimensional description of the anatomical wiring scheme defined by the in-section direction angle and the out-of-section inclination angle. To date, 3D-PLI is the only available method that allows bridging the microscopic and the macroscopic description of the fiber architecture of the human brain. Here we introduce a new approach to retrieve the inclination angle of the fibers independently of the properties of the used polarimeters. This is relevant because the image resolution and the signal transmission inuence the measured birefringent signal (retardation) significantly. The image resolution was determined using the USAF- 1951 testchart applying the Rayleigh criterion. The signal transmission was measured by elliptical polarizers applying the Michelson contrast and histological slices of the optic tract of a postmortem brain. Based on these results, a modified retardation-inclination transfer function was proposed to extract the fiber inclination. The comparison of the actual and the inclination angles calculated with the theoretically proposed and the modified transfer function revealed a significant improvement in the extraction of the fiber inclinations.

  4. Development and evaluation of an anchorage-independent agar-based clonal assay for human primary breast carcinoma cells

    SciTech Connect

    Besch, G.J.

    1985-01-01

    The development and evaluation of an anchorage-independent clonal cytotoxic assay for primary human breast carcinoma cells is described in this thesis. This assay was developed in three stages which include: (1) the optimization of the production of a monodispersed cell suspension from solid breast carcinomas, (2) the systematic development of a growth medium for the clonal growth of these cells, and (3) the adaptation of these methods for use in the quantitation of cytotoxicity. The results of these studies indicated that hydrocortisone, fetal bovine serum and red blood cells stimulated the clonal growth of breast carcinoma cells. The optimal concentrations of these three factors were simultaneously determined using response surface methodology. These culture conditions were then used to develop radiation-cytotoxicity assays for both primary and recurrent breast carcinomas. The methodology developed and evaluated in this thesis may be useful to: (1) study the biology and radiobiology of human breast cancer, (2) customize the treatment of individual breast cancer patients, and (3) identify and/or develop new drugs and/or other treatment modalities for breast cancer.

  5. Age-related telomere uncapping is associated with cellular senescence and inflammation independent of telomere shortening in human arteries.

    PubMed

    Morgan, Richard G; Ives, Stephen J; Lesniewski, Lisa A; Cawthon, Richard M; Andtbacka, Robert H I; Noyes, R Dirk; Richardson, Russell S; Donato, Anthony J

    2013-07-15

    Arterial telomere dysfunction may contribute to chronic arterial inflammation by inducing cellular senescence and subsequent senescence-associated inflammation. Although telomere shortening has been associated with arterial aging in humans, age-related telomere uncapping has not been described in non-cultured human tissues and may have substantial prognostic value. In skeletal muscle feed arteries from 104 younger, middle-aged, and older adults, we assessed the potential role of age-related telomere uncapping in arterial inflammation. Telomere uncapping, measured by p-histone γ-H2A.X (ser139) localized to telomeres (chromatin immunoprecipitation; ChIP), and telomeric repeat binding factor 2 bound to telomeres (ChIP) was greater in arteries from older adults compared with those from younger adults. There was greater tumor suppressor protein p53 (P53)/cyclin-dependent kinase inhibitor 1A (P21)-induced senescence, measured by P53 bound to P21 gene promoter (ChIP), and greater expression of P21, interleukin 8, and monocyte chemotactic protein 1 mRNA (RT-PCR) in arteries from older adults compared with younger adults. Telomere uncapping was a highly influential covariate for the age-group difference in P53/P21-induced senescence. Despite progressive age-related telomere shortening in human arteries, mean telomere length was not associated with telomere uncapping or P53/P21-induced senescence. Collectively, these findings demonstrate that advancing age is associated with greater telomere uncapping in arteries, which is linked to P53/P21-induced senescence independent of telomere shortening.

  6. Senescent mesenchymal cells accumulate in human fibrosis by a telomere-independent mechanism and ameliorate fibrosis through matrix metalloproteinases.

    PubMed

    Pitiyage, Gayani Nadika; Slijepcevic, Predrag; Gabrani, Aliya; Chianea, Yaghoub Gozaly; Lim, Kue Peng; Prime, Stephen Stewart; Tilakaratne, Wanninayake Mudiyanselage; Fortune, Farida; Parkinson, Eric Kenneth

    2011-04-01

    Fibrosis can occur in many organs, where it is a debilitating and preneoplastic condition. The senescence of activated fibroblasts has been proposed to ameliorate fibrosis via the innate immune system but its role in humans has not been investigated. The availability of oral submucous fibrosis (OSMF) biopsies at different stages of disease progression allowed us to test the hypothesis that senescent fibroblasts accumulate with the progression of human fibrosis in vivo, and also to examine the mechanism of senescence. We tested the hypothesis that senescent cells may ameliorate fibrosis by increasing the secretion of matrix metalloproteinases (MMPs). We have used a combination of in situ immunodetection techniques, drug treatments, fluorescence-activated cell sorting and enzyme-linked absorbance assays on tissue samples and fibroblast cultures. We report a novel panning technique, based on fibronectin adhesion rates, to enrich and deplete senescent cells from fibroblast populations. Senescent fibroblasts, as determined by the presence of senescence-associated heterochromatic foci, accumulated with OSMF progression (R(2) = 0.98) and possessed a reduced replicative lifespan in vitro. Unlike wounds, however, OSMF fibroblasts were quiescent in vivo and consistent with this observation, possessed functional telomeres of normal length. Senescence was associated in vivo and in vitro with oxidative damage, DNA damage foci and p16(INK4A) accumulation and required the production of reactive oxygen species (ROS), perhaps from damaged mitochondria, but not the continuous presence of the disease stimulus (areca nut and tobacco), the tissue environment or other cell types. Depletion of OSMF fibroblasts of senescent cells showed that these cells accounted for 25-83 times more MMP-1 and -2 than their pre-senescent counterparts. The results show that the accumulation of senescent fibroblasts in human fibrosis occurs by a telomere-independent mechanism involving ROS and may locally

  7. Synthetic Androgens as Designer Supplements

    PubMed Central

    Joseph, Jan Felix; Parr, Maria Kristina

    2015-01-01

    Anabolic androgenic steroids (AAS) are some of the most common performance enhancing drugs (PED) among society. Despite the broad spectrum of adverse effects and legal consequences, AAS are illicitly marketed and distributed in many countries. To circumvent existing laws, the chemical structure of AAS is modified and these designer steroids are sold as nutritional supplements mainly over the Internet. Several side effects are linked with AAS abuse. Only little is known about the pharmacological effects and metabolism of unapproved steroids due to the absence of clinical studies. The large number of designer steroid findings in dietary supplements and the detection of new compounds combined with legal loopholes for their distribution in many countries show that stricter regulations and better information policy are needed. PMID:26074745

  8. Synthetic androgens as designer supplements.

    PubMed

    Joseph, Jan Felix; Parr, Maria Kristina

    2015-01-01

    Anabolic androgenic steroids (AAS) are some of the most common performance enhancing drugs (PED) among society. Despite the broad spectrum of adverse effects and legal consequences, AAS are illicitly marketed and distributed in many countries. To circumvent existing laws, the chemical structure of AAS is modified and these designer steroids are sold as nutritional supplements mainly over the Internet. Several side effects are linked with AAS abuse. Only little is known about the pharmacological effects and metabolism of unapproved steroids due to the absence of clinical studies. The large number of designer steroid findings in dietary supplements and the detection of new compounds combined with legal loopholes for their distribution in many countries show that stricter regulations and better information policy are needed. PMID:26074745

  9. Genetics Home Reference: androgen insensitivity syndrome

    MedlinePlus

    ... typically raised as females and have a female gender identity. Affected individuals have male internal sex organs ( ... and may have a male or a female gender identity. People with mild androgen insensitivity are born ...

  10. The androgen receptor gene mutations database.

    PubMed

    Gottlieb, B; Trifiro, M; Lumbroso, R; Vasiliou, D M; Pinsky, L

    1996-01-01

    The current version of the androgen receptor (AR) gene mutations database is described. We have added (if available) data on the androgen binding phenotype of the mutant AR, the clinical phenotype of the affected persons, the family history and whether the pathogenicity of a mutation has been proven. Exonic mutations are now listed in 5'-->3' sequence regardless of type and single base pair changes are presented in codon context. Splice site and intronic mutations are listed separately. The database has allowed us to substantiate and amplify the observation of mutational hot spots within exons encoding the AR androgen binding domain. The database is available from EML (ftp://www.ebi.ac.uk/pub/databases/androgen) or as a Macintosh Filemaker file (MC33@musica.mcgill.ca).

  11. Androgen deprivation therapy for prostate cancer.

    PubMed

    Singer, Eric A; Golijanin, Dragan J; Miyamoto, Hiroshi; Messing, Edward M

    2008-02-01

    Androgen deprivation continues to play a crucial role in the treatment of advanced and metastatic prostate cancer. In the 65 years since its use was first described, urologists and medical oncologists have developed new and innovative ways to manipulate the hypothalamic-pituitary-gonadal axis with the goal of alleviating symptoms and prolonging the life of men with prostate cancer. Despite the successes that androgen deprivation therapy has brought, each method and regimen possesses unique benefits and burdens, of which the clinician and patient must be cognizant. This review discusses the first-line androgen deprivation methods and regimens presently in use with special attention paid to their side effects and the management of them, as well as the question of when to initiate androgen deprivation therapy.

  12. Acne vulgaris related to androgens - a review.

    PubMed

    Khondker, L; Khan, S I

    2014-01-01

    Sebum production is stimulated by androgens and is the key in the development of acne vulgaris. Several investigators have looked for direct relationships between serum androgen levels, sebum secretion rate and the presence of acne. The presence of acne in prepubertal girls and sebum production in both sexes correlate with serum dehydroepiandrosterone sulfate (DHEAS) levels. Although increased serum androgen levels correlate with the presence of severe nodular acne in men and women, these levels are often within the normal range in mild to moderate acne. This raises the question of whether there is an increased local production of androgens within the sebaceous gland of patients with acne vulgaris that leads to increased sebum secretion.

  13. Expression of novel genes linked to the androgen-induced, proliferative shutoff in prostate cancer cells.

    PubMed

    Geck, P; Szelei, J; Jimenez, J; Lin, T M; Sonnenschein, C; Soto, A M

    1997-01-01

    Androgens control cell numbers in the prostate through three separate pathways: (a) inhibition of cell death, (b) induction of cell proliferation (Step-1) and (c) inhibition of cell proliferation (Step-2, proliferative shutoff). The mechanisms underlying these phenomena are incompletely understood. The human prostate carcinoma LNCaP variants express these pathways as follows: LNCaP-FGC express both steps, LNCaP-LNO expresses Step-2, LNCaP-TAC expresses Step-1, and LNCaP-TJA cells express neither step. These cells facilitated the search for mediators of the androgen-induced proliferative shutoff pathway. Androgen exposure for 24 h or longer induced an irreversible proliferative shutoff in LNCaP-FGC cells. The Wang and Brown approach for identifying differentially expressed mRNAs was used to search for mediators of Step-2. Ten unique inserts were identified and from those ten, three genes were further studied. The basal expression of these genes in shutoff-negative variants was not affected by androgen exposure. They were induced by androgens in shutoff-positive LNCaP variants and the androgen receptor-transfected, shutoff-positive, MCF7-AR1 cells. These genes were induced only in the range of androgen concentrations that elicited the shutoff response. Time course analysis showed that their induction precedes the commitment point by 12-18 h. In addition, they were expressed in the normal prostate during proliferative shutoff. These features suggest that the candidate genes have a role in the regulation cascade for proliferative shutoff.

  14. Effects of Aromatase Inhibition and Androgen Activity on Serotonin and Behavior in Male Macaques

    PubMed Central

    Bethea, Cynthia L.; Reddy, Arubala P.; Robertson, Nicola; Colemen, Kristine

    2014-01-01

    Aggression in humans and animals has been linked to androgens and serotonin function. To further our understanding of the effect of androgens on serotonin and aggression in male macaques, we sought to manipulate circulating androgens and the activity of aromatase; and to then determine behavior and the endogenous availability of serotonin. Male Japanese macaques (Macaca fuscata) were castrated for 5-7 months and then treated for 3 months with [1] placebo, [2] testosterone (T), [3] T+Dutasteride (5a reductase inhibitor; AvodartTM), [4] T+Letrozole (non-steroidal aromatase inhibitor; FemeraTM), [5] Flutamide+ATD (androgen antagonist plus steroidal aromatase inhibitor) or [6] dihydrotestosterone (DHT)+ATD (n=5/group). Behavioral observations were made during treatments. At the end of the treatment period, each animal was sedated with propofol and administered a bolus of fenfluramine (5 mg/kg). Fenfluramine causes the release of serotonin proportional to endogenous availability and in turn, serotonin stimulates the secretion of prolactin. Therefore, serum prolactin concentrations reflect endogenous serotonin. Fenfluramine significantly increased serotonin/prolactin in all groups (p <0.0001). Fenfluramine-induced serotonin/prolactin in the T-treated group was significantly higher than the other groups (p<0.0001). Castration partially reduced the serotonin/prolactin response; and Letrozole partially blocked the effect of T. Complete inhibition of aromatase with ATD, a non-competitve inhibitor, significantly and similarly reduced the fenfluramine-induced serotonin/prolactin response in the presence or absence of DHT. Neither aggressive behavior nor yawning (indicators of androgen activity) correlated with serotonin/prolactin, but posited aromatase activity correlated significantly with prolactin (p<0.0008; r2 =0.95). In summary, androgens induced aggressive behavior but they did not regulate serotonin. Altogether, the data suggest that aromatase activity supports

  15. Effects of aromatase inhibition and androgen activity on serotonin and behavior in male macaques.

    PubMed

    Bethea, Cynthia L; Reddy, Arubala P; Robertson, Nicola; Coleman, Kristine

    2013-06-01

    Aggression in humans and animals has been linked to androgens and serotonin function. To further our understanding of the effect of androgens on serotonin and aggression in male macaques, we sought to manipulate circulating androgens and the activity of aromatase; and to then determine behavior and the endogenous availability of serotonin. Male Japanese macaques (Macaca fuscata) were castrated for 5-7 months and then treated for 3 months with (a) placebo; (b) testosterone (T); (c) T + Dutasteride (5a reductase inhibitor; AvodartTM); (d) T + Letrozole (nonsteroidal aromatase inhibitor; FemeraTM); (e) Flutamide + ATD (androgen antagonist plus steroidal aromatase inhibitor); or (f) dihydrotestosterone (DHT) + ATD (n = 5/group). Behavioral observations were made during treatments. At the end of the treatment period, each animal was sedated with propofol and administered a bolus of fenfluramine (5 mg/kg). Fenfluramine causes the release of serotonin proportional to endogenous availability and in turn, serotonin stimulates the secretion of prolactin. Therefore, serum prolactin concentrations reflect endogenous serotonin. Fenfluramine significantly increased serotonin/prolactin in all groups (p < .0001). Fenfluramine-induced serotonin/prolactin in the T-treated group was significantly higher than the other groups (p < .0001). Castration partially reduced the serotonin/prolactin response and Letrozole partially blocked the effect of T. Complete inhibition of aromatase with ATD, a noncompetitive inhibitor, significantly and similarly reduced the fenfluramine-induced serotonin/prolactin response in the presence or absence of DHT. Neither aggressive behavior nor yawning (indicators of androgen activity) correlated with serotonin/prolactin, but posited aromatase activity correlated significantly with prolactin (p < .0008; r² = 0.95). In summary, androgens induced aggressive behavior but they did not regulate serotonin. Altogether, the data suggest that aromatase activity

  16. Androgen deprivation treatment of sexual behavior.

    PubMed

    Houts, Frederick W; Taller, Inna; Tucker, Douglas E; Berlin, Fred S

    2011-01-01

    Gonadotropin-releasing hormone agonists are underutilized in patients seeking diminution of problematic sexual drives. This chapter reviews the literature on surgical castration of sex offenders, anti-androgen use and the rationale for providing androgen deprivation therapy, rather than selective serotonin reuptake inhibitors or more conservative interventions, for patients with paraphilias and excessive sexual drive. Discussions of informed consent, side effects, contraindications and case examples are provided.

  17. Androgen deprivation treatment of sexual behavior.

    PubMed

    Houts, Frederick W; Taller, Inna; Tucker, Douglas E; Berlin, Fred S

    2011-01-01

    Gonadotropin-releasing hormone agonists are underutilized in patients seeking diminution of problematic sexual drives. This chapter reviews the literature on surgical castration of sex offenders, anti-androgen use and the rationale for providing androgen deprivation therapy, rather than selective serotonin reuptake inhibitors or more conservative interventions, for patients with paraphilias and excessive sexual drive. Discussions of informed consent, side effects, contraindications and case examples are provided. PMID:22005210

  18. Androgen receptor in male breast cancer.

    PubMed

    Sas-Korczynska, Beata; Adamczyk, Aagnieszka; Niemiec, Joanna; Harazin-Lechowska, Agnieszka; Ambicka, Aleksandra; Jakubowicz, Jerzy

    2015-12-01

    We present the androgen receptor (AR) status in 32 breast cancers diagnosed in male patients. Androgen receptor expression was found in 62.5% tumors and it was more frequent (85% of cases) in estrogen-positive tumours. The analyses of its impact on treatment results showed that AR immmunopositivity is a prognostic factor for overall survival, and AR immunonegativity is also correlated with worse prognosis (distant metastases developed more frequently and earlier).

  19. Androgen receptor expression in gastrointestinal stromal tumor.

    PubMed

    Lopes, Lisandro F; Bacchi, Carlos E

    2009-03-01

    The aim of this study was to evaluate the expression of estrogen, progesterone, and androgen receptors in a large series of gastrointestinal stromal tumors. Clinical and pathologic data were reviewed in 427 cases of gastrointestinal stromal tumor and the expression of such hormone receptors was investigated by immunohistochemistry using tissue microarray technique. All tumors were negative for estrogen receptor expression. Progesterone and androgen receptors expression was observed in 5.4% and 17.6% of tumors, respectively. We found the higher average age at diagnosis, the lower frequency of tumors located in the small intestine, and the higher frequency of extragastrointestinal tumors to be statistically significant in the group of tumors with androgen receptor expression in contrast to the group showing no androgen receptor expression. There was no statistic difference between such groups regarding sex, tumor size, mitotic count, cell morphology, and risk of aggressive behavior. Considering that the expression of androgen receptors in gastrointestinal stromal tumors is not negligible, further studies are encouraged to establish the role of androgen deprivation therapy for gastrointestinal stromal tumors.

  20. Assessment of human embryos by time-lapse videography: A comparison of quantitative and qualitative measures between two independent laboratories.

    PubMed

    Liu, Yanhe; Copeland, Christopher; Stevens, Adam; Feenan, Katie; Chapple, Vincent; Myssonski, Kim; Roberts, Peter; Matson, Phillip

    2015-12-01

    A total of 488 Day 3 human embryos with known implantation data from two independent in vitro fertilization laboratories were included for analysis, with 270 from Fertility North (FN) and 218 from Canberra Fertility Centre (CFC). Implanting embryos grew at different rates between FN and CFC as indicated in hours of the time intervals between pronuclear fading and the 4- (13.9 ± 1.1 vs. 14.9 ± 1.8), 5- (25.7 ± 1.9 vs. 28.4 ± 3.7) and 8-cell stages (29.0 ± 3.2 vs. 32.2 ± 4.6), as well as the durations of 2- (10.8 ± 0.8 vs. 11.6 ± 1.1), 3- (0.4 ± 0.5 vs. 0.9 ± 1.2), and 4-cell stages (11.8 ± 1.4 vs. 13.6 ± 2.9), all p<0.05. The application of a previously published time-lapse algorithm on ICSI embryos from the two participating laboratories failed to reproduce a predictive pattern of implantation outcomes (FN: AUC=0.565, p=0.250; CFC: AUC=0.614, p=0.224). However, for the qualitative measures including poor conventional morphology, direct cleavage, reverse cleavage and <6 intercellular contact points at the end of the 4-cell stage, there were similar proportions of embryos showing at least one of these biological events in either implanting (3.1% vs. 3.3%, p>0.05) or non-implanting embryos (30.4% vs. 38.3%, p>0.05) between FN and CFC. Furthermore, implanting embryos favored lower proportions of the above biological events compared to the non-implanting ones in both laboratories (both p<0.01). To conclude, human embryo morphokinetics may vary between laboratories, therefore time-lapse algorithms emphasizing quantitative timing parameters may have reduced inter-laboratory transferability; qualitative measures are independent of cell division timings, with potentially improved inter-laboratory reproducibility.

  1. Illicit anabolic-androgenic steroid use.

    PubMed

    Kanayama, Gen; Hudson, James I; Pope, Harrison G

    2010-06-01

    The anabolic-androgenic steroids (AAS) are a family of hormones that includes testosterone and its derivatives. These substances have been used by elite athletes since the 1950s, but they did not become widespread drugs of abuse in the general population until the 1980s. Thus, knowledge of the medical and behavioral effects of illicit AAS use is still evolving. Surveys suggest that many millions of boys and men, primarily in Western countries, have abused AAS to enhance athletic performance or personal appearance. AAS use among girls and women is much less common. Taken in supraphysiologic doses, AAS show various long-term adverse medical effects, especially cardiovascular toxicity. Behavioral effects of AAS include hypomanic or manic symptoms, sometimes accompanied by aggression or violence, which usually occur while taking AAS, and depressive symptoms occurring during AAS withdrawal. However, these symptoms are idiosyncratic and afflict only a minority of illicit users; the mechanism of these idiosyncratic responses remains unclear. AAS users may also ingest a range of other illicit drugs, including both "body image" drugs to enhance physical appearance or performance, and classical drugs of abuse. In particular, AAS users appear particularly prone to opioid use. There may well be a biological basis for this association, since both human and animal data suggest that AAS and opioids may share similar brain mechanisms. Finally, AAS may cause a dependence syndrome in a substantial minority of users. AAS dependence may pose a growing public health problem in future years but remains little studied.

  2. Illicit Anabolic-Androgenic Steroid Use

    PubMed Central

    Kanayama, Gen; Hudson, James I.; Pope, Harrison G.

    2009-01-01

    The anabolic-androgenic steroids (AAS) are a family of hormones that includes testosterone and its derivatives. These substances have been used by elite athletes since the 1950s, but they did not become widespread drugs of abuse in the general population until the 1980s. Thus, knowledge of the medical and behavioral effects of illicit AAS use is still evolving. Surveys suggest that many millions of boys and men, primarily in Western countries, have abused AAS to enhance athletic performance or personal appearance. AAS use among girls and women is much less common. Taken in supraphysiologic doses, AAS show various long-term adverse medical effects, especially cardiovascular toxicity. Behavioral effects of AAS include hypomanic or manic symptoms, sometimes accompanied by aggression or violence, which usually occur while taking AAS, and depressive symptoms occurring during AAS withdrawal. However, these symptoms are idiosyncratic and afflict only a minority of illicit users; the mechanism of these idiosyncratic responses remains unclear. AAS users may also ingest a range of other illicit drugs, including both “body-image” drugs to enhance physical appearance or performance, and classical drugs of abuse. In particular, AAS users appear particularly prone to opioid use. There may well be a biological basis for this association, since both human and animal data suggest that AAS and opioids may share similar brain mechanisms. Finally, AAS may cause a dependence syndrome in a substantial minority of users. AAS dependence may pose a growing public health problem in future years, but remains little studied. PMID:19769977

  3. Dihomo-gamma-linolenic acid inhibits tumour necrosis factor-alpha production by human leucocytes independently of cyclooxygenase activity.

    PubMed

    Dooper, Maaike M B W; van Riel, Boet; Graus, Yvo M F; M'Rabet, Laura

    2003-11-01

    Dietary oils (such as borage oil), which are rich in gamma-linolenic acid (GLA), have been shown to be beneficial under inflammatory conditions. Dihomo-GLA (DGLA) is synthesized directly from GLA and forms a substrate for cyclooxygenase (COX) enzymes, resulting in the synthesis of lipid mediators (eicosanoids). In the present study, the immunomodulatory effects of DGLA were investigated and compared with those of other relevant fatty acids. Freshly isolated human peripheral blood mononuclear cells (PBMC) were cultured in fatty acid (100 microm)-enriched medium for 48 hr. Subsequently, cells were stimulated with lipopolysaccharide (LPS) for 20 hr and the cytokine levels were measured, in supernatants, by enzyme-linked immunosorbent assay (ELISA). Phospholipids were analysed by gas chromatography. Fatty acids were readily taken up, metabolized and incorporated into cellular phospholipids. Compared with the other fatty acids tested, DGLA exerted pronounced modulatory effects on cytokine production. Tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-10 levels were reduced to 60% of control levels, whereas IL-6 levels were not affected by DGLA. Kinetic studies showed that peak levels of TNF-alpha, occurring early after LPS addition, were inhibited strongly, whereas IL-10 levels were not affected until 15 hr after stimulation. Both the reduction of cytokine levels and the decrease in arachidonic acid levels in these cells, induced by DGLA, were dose dependent, suggesting a shift in eicosanoid-subtype synthesis. However, although some DGLA-derived eicosanoids similarly reduced TNF-alpha levels, the effects of DGLA were probably not mediated by COX products, as the addition of indomethacin did not alter the effects of DGLA. In conclusion, these results suggest that DGLA affects cytokine production by human PBMC independently of COX activation. PMID:14632663

  4. Functional Diversity of Human Mitochondrial J-proteins Is Independent of Their Association with the Inner Membrane Presequence Translocase.

    PubMed

    Sinha, Devanjan; Srivastava, Shubhi; D'Silva, Patrick

    2016-08-12

    Mitochondrial J-proteins play a critical role in governing Hsp70 activity and, hence, are essential for organellar protein translocation and folding. In contrast to yeast, which has a single J-protein Pam18, humans involve two J-proteins, DnaJC15 and DnaJC19, associated with contrasting cellular phenotype, to transport proteins into the mitochondria. Mutation in DnaJC19 results in dilated cardiomyopathy and ataxia syndrome, whereas expression of DnaJC15 regulates the response of cancer cells to chemotherapy. In the present study we have comparatively assessed the biochemical properties of the J-protein paralogs in relation to their association with the import channel. Both DnaJC15 and DnaJC19 formed two distinct subcomplexes with Magmas at the import channel. Knockdown analysis suggested an essential role for Magmas and DnaJC19 in organellar protein translocation and mitochondria biogenesis, whereas DnaJC15 had dispensable supportive function. The J-proteins were found to have equal affinity for Magmas and could stimulate mitochondrial Hsp70 ATPase activity by equivalent levels. Interestingly, we observed that DnaJC15 exhibits bifunctional properties. At the translocation channel, it involves conserved interactions and mechanism to translocate the precursors into mitochondria. In addition to protein transport, DnaJC15 also showed a dual role in yeast where its expression elicited enhanced sensitivity of cells to cisplatin that required the presence of a functional J-domain. The amount of DnaJC15 expressed in the cell was directly proportional to the sensitivity of cells. Our analysis indicates that the differential cellular phenotype displayed by human mitochondrial J-proteins is independent of their activity and association with Magmas at the translocation channel.

  5. An Independent Human Factors Analysis and Evaluation of the Emergency Medical Protocol Checklist for the International Space Station

    NASA Technical Reports Server (NTRS)

    Marshburn, Thomas; Whitmore, Mihriban; Ortiz, Rosie; Segal, Michele; Smart, Kieran; Hughes, Catherine

    2003-01-01

    Emergency medical capabilities aboard the ISS include a Crew Medical Officer (CMO) (not necessarily a physician), and back-up, resuscitation equipment, and a medical checklist. It is essential that CMOs have reliable, usable and informative medical protocols that can be carried out independently in flight. The study evaluates the existing ISS Medical Checklist layout against a checklist updated to reflect a human factors approach to structure and organization. Method: The ISS Medical checklist was divided into non-emergency and emergency sections, and re-organized based on alphabetical and a body systems approach. A desk-top evaluation examined the ability of subjects to navigate to specific medical problems identified as representative of likely non-emergency events. A second evaluation aims to focus on the emergency section of the Medical Checklist, based on the preliminary findings of the first. The final evaluation will use Astronaut CMOs as subjects comparing the original checklist against the updated layout in the task of caring for a "downed crewmember" using a Human Patient Simulator [Medical Education Technologies, Inc.]. Results: Initial results have demonstrated a clear improvement of the re-organized sections to determine the solution to the medical problems. There was no distinct advantage for either alternative, although subjects stated having a preference for the body systems approach. In the second evaluation, subjects will be asked to identify emergency medical conditions, with measures including correct diagnosis, time to completion and solution strategy. The third evaluation will compare the original and fully updated checklists in clinical situations. Conclusions: Initial findings indicate that the ISS Medical Checklist will benefit from a reorganization. The present structure of the checklist has evolved over recent years without systematic testing of crewmember ability to diagnose medical problems. The improvements are expected to enable ISS