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Sample records for a-induced aromatase activation

  1. RELATIONSHIP BETWEEN BRAIN AND OVARY AROMATASE ACTIVITY AND ISOFORM-SPECIFIC AROMATASE MRNA EXPRESSION IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    There is growing evidence that some chemicals present in the environment have the capacity to inhibit, or potentially induce, aromatase activity. This study compared aromatase activities and isoform-specific mRNA expression in brain and ovary tissue from non-exposed fathead min...

  2. Aromatase inhibitor associated musculoskeletal symptoms are associated with reduced physical activity among breast cancer survivors.

    PubMed

    Brown, Justin C; Mao, Jun J; Stricker, Carrie; Hwang, Wei-Ting; Tan, Kay-See; Schmitz, Kathryn H

    2014-01-01

    Physical activity (PA) has numerous health benefits for breast cancer survivors. Recent data suggest that some breast cancer survivors treated with aromatase inhibitors may experience aromatase inhibitor associated musculoskeletal symptoms. It is unknown whether aromatase inhibitor associated musculoskeletal symptoms are associated with reduced PA and what other risk factors are associated with such PA reductions. We conducted a cross-sectional study at a large university-based breast cancer clinic among breast cancer survivors prescribed an aromatase inhibitor. At routine follow-up, we surveyed participants about aromatase inhibitor associated musculoskeletal symptoms, as well as pre-aromatase inhibitor, and current, PA levels. Among 300 participants, 90 (30%) reported a reduction of PA since the initiation of aromatase inhibitor therapy. Those with aromatase inhibitor associated musculoskeletal symptoms were more likely to report decreased PA (62% versus 38%, p = 0.001) compared with those without aromatase inhibitor associated musculoskeletal symptoms. In multivariate analyses, aromatase inhibitor associated musculoskeletal symptoms (odds ratio [OR] = 2.29 [95% confidence interval [CI]: 1.36-3.86]), and body mass index (OR = 1.06 [95% CI: 1.02-1.12]) were associated with reductions in PA. In subgroup analysis among breast cancer survivors with aromatase inhibitor associated musculoskeletal symptoms, self-reported lower extremity joint pain (OR = 1.23 [95% CI: 1.00-1.50]) and impaired lower extremity physical function (OR = 1.07 [95% CI: 1.01-1.14]) were associated with reductions in PA. Breast cancer survivors with aromatase inhibitor associated musculoskeletal symptoms were more likely to report reductions in PA since initiating aromatase inhibitor therapy compared with those without aromatase inhibitor associated musculoskeletal symptoms. Our findings suggest that tailored interventions targeting lower extremity functional limitations are needed to enable

  3. RELATIONSHIP BETWEEN BRAIN AND OVARY AROMATASE ACTIVITY AND ISOFORM-SPECIFIC AROMATASE MRNA EXPRESSION IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS) - JOURNAL ARTICLE

    EPA Science Inventory

    There is growing evidence that some chemicals present in the environment have the capacity to inhibit, or potentially induce, aromatase activity. This study compared aromatase activities and isoform-specific mRNA expression in brain and ovary tissue from non-exposed fathead minn...

  4. Prevention and treatment of breast cancer by suppressing aromatase activity and expression.

    PubMed

    Chen, Shiuan; Zhou, Dujin; Okubo, Tomoharu; Kao, Yeh-Chih; Eng, Elizabeth T; Grube, Baiba; Kwon, Annette; Yang, Chun; Yu, Bin

    2002-06-01

    Estrogen promotes the proliferation of breast cancer cells. Aromatase is the enzyme that converts androgen to estrogen. In tumors, expression of aromatase is upregulated compared to that of surrounding noncancerous tissue. Tumor aromatase is thought to stimulate breast cancer growth in both an autocrine and a paracrine manner. A treatment strategy for breast cancer is to abolish in situ estrogen formation with aromatase inhibitors. In addition, aromatase suppression in postmenapausal women is being evaluated as a potential chemopreventive modality against breast cancer. One area of aromatase research in this laboratory is the identification of foods and dietary compounds that can suppress aromatase activity. In vitro and in vivo studies have found that grapes and mushrooms contain chemicals that can inhibit aromatase. Therefore, a diet that includes grapes and mushrooms would be considered preventative against breast cancer. Another area of our aromatase research is the elucidation of the regulatory mechanism of aromatase expression in breast cancer tissue. Increased aromatase expression in breast tumors is attributed to changes in the transcriptional control of aromatase expression. Whereas promoter I.4 is the main promoter that controls aromatase expression in noncancerous breast tissue, promoters II and I.3 are the dominant promoters that drive aromatase expression in breast cancer tissue. Our recent gene regulation studies revealed that in cancerous versus normal tissue, several positive regulatory proteins (e.g., nuclear receptors and CREB1) are present at higher levels and several negative regulatory proteins (e.g., snail and slug proteins) are present at lower levels. This may explain why the activity of promoters II and I.3 is upregulated in cancerous tissue. In addition, our in vitro transcription/translation analysis using plasmids containing T7 promoter and the human snail gene as a reporter capped with different untranslated exon Is revealed that exon

  5. Regulation of aromatase activity in bone-derived cells: possible role of mitogen-activated protein kinase.

    PubMed

    Shozu, M; Sumitani, H; Murakami, K; Segawa, T; Yang, H J; Inoue, M

    2001-12-01

    Fetal human osteoblast-like cells and the THP-1 cell line that differentiates into macrophage/osteoblast-like cells in the presence of Vitamin D3 and which possesses high aromatase activity, constitute a useful model with which to study the regulation of aromatase in bone. We showed that dexamethasone (DEX)-induced aromatase activity in the THP-1 cell line is completely suppressed by forskolin and by dibutyryl cAMP. We therefore investigated the contribution of mitogen-activated protein kinase (MAPK) to the regulation of aromatase, because cAMP inhibits MAPK in many cells. We examined the role of MAPK on aromatase activity using PD98059, a selective inhibitor of MEK-1. PD98059 (100 microM) reduced DEX+interleukin (IL)-1beta-induced aromatase activity in human osteoblast-like cells by more than 90%, whereas 50% of the aromatase mRNA concentration was retained compared with the control incubated with DEX+IL-1beta. PD98059 (50 microM) reduced the activity of aromatase in THP-1 cells by 80% without significantly affecting the mRNA level. These results indicated that MAPK plays an important role in aromatase activation at the post-transcriptional level.

  6. Rapid decreases in preoptic aromatase activity and brain monoamine concentrations after engaging in male sexual behavior

    PubMed Central

    Cornil, C. A.; Dalla, C.; Papadopoulou-Daifoti, Z.; Baillien, M.; Dejace, C.; Ball, G.F.; Balthazart, J.

    2014-01-01

    In Japanese quail as in rats, the expression of male sexual behavior over relatively long time periods (days to weeks) is dependent on the local production of estradiol in the preoptic area via the aromatization of testosterone. On a short-term basis (minutes to hours), central actions of dopamine as well as locally produced estrogens modulate behavioral expression. In rats, a view of and sexual interaction with a female increases dopamine release in the preoptic area. In quail, in vitro brain aromatase activity is rapidly modulated by calcium-dependent phosphorylations that are likely to occur in vivo as a result of changes in neurotransmitter activity. Furthermore, an acute estradiol injection rapidly stimulates copulation in quail, while a single injection of the aromatase inhibitor Vorozole™ rapidly inhibits this behavior. We hypothesized that brain aromatase and dopaminergic activities are regulated in quail in association with the expression of male sexual behavior. Visual access as well as sexual interactions with a female produced a significant decrease in brain aromatase activity that was maximal after 5 min. This expression of sexual behavior also resulted in a significant decrease in dopaminergic as well as serotonergic activity after 1 min, which returned to basal levels after 5 min. These results demonstrate for the first time that aromatase activity is rapidly modulated in vivo in parallel with changes in dopamine activity. Sexual interactions with the female decreased aromatase and dopamine activity. These data challenges established views about the causal relationships among dopamine, estrogen action and male sexual behavior. PMID:15932925

  7. Leptin induces CREB-dependent aromatase activation through COX-2 expression in breast cancer cells.

    PubMed

    Kim, Hyung Gyun; Jin, Sun Woo; Kim, Yong An; Khanal, Tilak; Lee, Gi Ho; Kim, Se Jong; Rhee, Sang Dal; Chung, Young Chul; Hwang, Young Jung; Jeong, Tae Cheon; Jeong, Hye Gwang

    2017-08-01

    Leptin plays a key role in the control of adipocyte formation, as well as in the associated regulation of energy intake and expenditure. The goal of this study was to determine if leptin-induced aromatase enhances estrogen production and induces tumor cell growth stimulation. To this end, breast cancer cells were incubated with leptin in the absence or presence of inhibitor pretreatment, and changes in aromatase and cyclooxygenase-2 (COX-2) expression were evaluated at the mRNA and protein levels. Transient transfection assays were performed to examine the aromatase and COX-2 gene promoter activities and immunoblot analysis was used to examine protein expression. Leptin induced aromatase expression, estradiol production, and promoter activity in breast cancer cells. Protein levels of phospho-STAT3, PKA, Akt, ERK, and JNK were increased by leptin. Leptin also significantly increased cAMP levels, cAMP response element (CRE) activation, and CREB phosphorylation. In addition, leptin induced COX-2 expression, promoter activity, and increased the production of prostaglandin E 2 . Finally, a COX-2 inhibitor and aromatase inhibitor suppressed leptin-induced cell proliferation in MCF-7 breast cancer cells. Together, our data show that leptin increased aromatase expression in breast cancer cells, which was correlated with COX-2 upregulation, mediated through CRE activation and cooperation among multiple signaling pathways. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Identification of aromatase activity in rodent pituitary cell strains.

    PubMed

    Callard, G V; Petro, Z; Tashjian, A H

    1983-07-01

    To date, biochemical evidence has been presented for hypophysial aromatization in only one species, a teleost fish, although the pituitary glands of several mammals have been reported to be aromatase negative. To reinvestigate this problem, established clonal strains of rodent pituitary cells (GH3, GH4C1, and AtT20/D16) were incubated at 37 C for 6-48 h in serum-less medium containing [7-3H]androstenedione. Radiolabeled metabolites were isolated by solvent extraction, thin layer chromatography, and phenolic partition. The authenticity of the estrogenic products in both cells and incubation medium was verified by methylation and recrystallization to constant specific activity. Measurement of androgen metabolites was also validated by recrystallization of selected samples. Authentic estrone and 17 beta-estradiol were identified in cultures of the two PRL- and GH-secreting clones, and there were strain differences in the quantity of estrogen produced (GH3 greater than GH4C1). Under the same conditions, aromatization was not detectable in the ACTH-secreting line (AtT20/D16). A time-yield analysis of androgen metabolism in GH4C1 cells showed that aromatization was linear for 12 h after labeling, but that substrate was diverted mainly to 5 alpha-reducing pathways. Large amounts of highly polar metabolites accumulated 24 and 48 h after the addition of [3H]androgen, and subsequent hydrolysis revealed that these were sulfo- and glucuronoconjugates. The metabolic fate of estrogen in GH4C1 cultures was investigated indirectly by adding a radioinert estrone trap together with the radiolabeled androgen substrate and was also tested in separate cultures by adding [3H]estrone and [3H]estradiol directly. Although the two estrogens were interconverted, there was no evidence that formed or added estrogen was extensively metabolized or conjugated. We conclude that the expression of aromatase activity in hypophysial cells is not a property of all transformed lines but may be dictated

  9. REPRODUCTION AND AROMATASE ACTIVITY IN THE MARINE FISH CUNNER (TAUTOGOLABROUS ADSPERSUS) EXPOSED TO ATRAZINE AND OCTYLPHENOL IN THE LABORATORY

    EPA Science Inventory

    This study was conducted to test the hypothesis that reproduction in fish is altered by exposure to endocrine-disrupting chemicals (EDCs) that modify aromatase activity. Aromatase, a product of the CYP19 gene, is the enzyme that catalyzes the conversion of the androgens androst...

  10. Rapid decreases in preoptic aromatase activity and brain monoamine concentrations after engaging in male sexual behavior.

    PubMed

    Cornil, C A; Dalla, C; Papadopoulou-Daifoti, Z; Baillien, M; Dejace, C; Ball, G F; Balthazart, J

    2005-09-01

    In Japanese quail, as in rats, the expression of male sexual behavior over relatively long time periods (days to weeks) is dependent on the local production of estradiol in the preoptic area via the aromatization of testosterone. On a short-term basis (minutes to hours), central actions of dopamine as well as locally produced estrogens modulate behavioral expression. In rats, a view of and sexual interaction with a female increase dopamine release in the preoptic area. In quail, in vitro brain aromatase activity (AA) is rapidly modulated by calcium-dependent phosphorylations that are likely to occur in vivo as a result of changes in neurotransmitter activity. Furthermore, an acute estradiol injection rapidly stimulates copulation in quail, whereas a single injection of the aromatase inhibitor vorozole rapidly inhibits this behavior. We hypothesized that brain aromatase and dopaminergic activities are regulated in quail in association with the expression of male sexual behavior. Visual access as well as sexual interactions with a female produced a significant decrease in brain AA, which was maximal after 5 min. This expression of sexual behavior also resulted in a significant decrease in dopaminergic as well as serotonergic activity after 1 min, which returned to basal levels after 5 min. These results demonstrate for the first time that AA is rapidly modulated in vivo in parallel with changes in dopamine activity. Sexual interactions with the female decreased aromatase and dopamine activities. These data challenge established views about the causal relationships among dopamine, estrogen action, and male sexual behavior.

  11. Discrete Fourier Transform-Based Multivariate Image Analysis: Application to Modeling of Aromatase Inhibitory Activity.

    PubMed

    Barigye, Stephen J; Freitas, Matheus P; Ausina, Priscila; Zancan, Patricia; Sola-Penna, Mauro; Castillo-Garit, Juan A

    2018-02-12

    We recently generalized the formerly alignment-dependent multivariate image analysis applied to quantitative structure-activity relationships (MIA-QSAR) method through the application of the discrete Fourier transform (DFT), allowing for its application to noncongruent and structurally diverse chemical compound data sets. Here we report the first practical application of this method in the screening of molecular entities of therapeutic interest, with human aromatase inhibitory activity as the case study. We developed an ensemble classification model based on the two-dimensional (2D) DFT MIA-QSAR descriptors, with which we screened the NCI Diversity Set V (1593 compounds) and obtained 34 chemical compounds with possible aromatase inhibitory activity. These compounds were docked into the aromatase active site, and the 10 most promising compounds were selected for in vitro experimental validation. Of these compounds, 7419 (nonsteroidal) and 89 201 (steroidal) demonstrated satisfactory antiproliferative and aromatase inhibitory activities. The obtained results suggest that the 2D-DFT MIA-QSAR method may be useful in ligand-based virtual screening of new molecular entities of therapeutic utility.

  12. Pyridine-substituted thiazolylphenol derivatives: Synthesis, modeling studies, aromatase inhibition, and antiproliferative activity evaluation.

    PubMed

    Ertas, Merve; Sahin, Zafer; Berk, Barkin; Yurttas, Leyla; Biltekin, Sevde N; Demirayak, Seref

    2018-04-01

    Drugs used in breast cancer treatments target the suppression of estrogen biosynthesis. During this suppression, the main goal is to inhibit the aromatase enzyme that is responsible for the cyclization and structuring of estrogens either with steroid or non-steroidal-type inhibitors. Non-steroidal derivatives generally have a planar aromatic structure attached to the triazole ring system in their structures, which inhibits hydroxylation reactions during aromatization by coordinating the heme group. Bioisosteric replacement of the triazole ring system and development of aromatic/cyclic structures of the side chain can increase the selectivity for aromatase enzyme inhibition. In this study, pyridine-substituted thiazolylphenol derivatives, which are non-steroidal triazole bioisosteres, were synthesized using the Hantzsch method, and physical analysis and structural determination studies were performed. The IC 50 values of the compounds were determined by a fluorescence-based aromatase inhibition assay. Then, their antiproliferative activities on the MCF7 and HEK 293 cell lines were evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, the crystal structure of human placental aromatase was subjected to a series of docking experiments to identify the possible interactions between the most active structure and the active site. Lastly, an in silico technique was performed to analyze and predict the drug-likeness, molecular and ADME properties of the synthesized molecules. © 2018 Deutsche Pharmazeutische Gesellschaft.

  13. Effects of Pharmaceuticals Used for Breast Cancer Treatment on Reproduction and Aromatase Activity in a Marine Fish

    EPA Science Inventory

    Laboratory experiments were conducted with the marine fish cunner (Tautogolabrus adspersus) to evaluate whether four pharmaceuticals used in breast cancer treatment have an impact on reproduction or aromatase activity. Tamoxifen binds to estrogen receptors, while anastrozole, let...

  14. Aromatase inhibitory activity of 1,4-naphthoquinone derivatives and QSAR study

    PubMed Central

    Prachayasittikul, Veda; Pingaew, Ratchanok; Worachartcheewan, Apilak; Sitthimonchai, Somkid; Nantasenamat, Chanin; Prachayasittikul, Supaluk; Ruchirawat, Somsak; Prachayasittikul, Virapong

    2017-01-01

    A series of 2-amino(chloro)-3-chloro-1,4-naphthoquinone derivatives (1-11) were investigated for their aromatase inhibitory activities. 1,4-Naphthoquinones 1 and 4 were found to be the most potent compounds affording IC50 values 5.2 times lower than the reference drug, ketoconazole. A quantitative structure-activity relationship (QSAR) model provided good predictive performance (R2CV = 0.9783 and RMSECV = 0.0748) and indicated mass (Mor04m and H8m), electronegativity (Mor08e), van der Waals volume (G1v) and structural information content index (SIC2) descriptors as key descriptors governing the activity. To investigate the effects of structural modifications on aromatase inhibitory activity, the model was employed to predict the activities of an additional set of 39 structurally modified compounds constructed in silico. The prediction suggested that the 2,3-disubstitution of 1,4-naphthoquinone ring with halogen atoms (i.e., Br, I and F) is the most effective modification for potent activity (1a, 1b and 1c). Importantly, compound 1b was predicted to be more potent than its parent compound 1 (11.90-fold) and the reference drug, letrozole (1.03-fold). The study suggests the 1,4-naphthoquinone derivatives as promising compounds to be further developed as a novel class of aromatase inhibitors. PMID:28827987

  15. Aromatase activity modulation by lindane and bisphenol-A in human placental JEG-3 and transfected kidney E293 cells.

    PubMed

    Nativelle-Serpentini, C; Richard, S; Séralini, G-E; Sourdaine, P

    2003-08-01

    Aromatase is the cytochrome P-450 involved in converting androgens to estrogens. The cytochrome P-450 family plays a central role in the oxidative metabolism of compounds including environmental pollutants. Since lindane and bisphenol-A (BPA) are two well-characterized endocrine disruptors that have been detected in animals and humans, it was important to learn whether they could affect aromatase activity and consequently estrogen biosynthesis. The present study investigates the effects of BPA and lindane on cytotoxicity, aromatase activity and mRNA levels in human placental JEG-3 cells and transfected human embryonal kidney 293 cells. Both cell lines were exposed to increasing concentrations of lindane (25, 50 and 75 microM) and bisphenol-A (25, 50 and 100 microM) over different time periods (10 min-18 h). As a result, none of these concentrations showed cytotoxicity. After short pre-incubation times (10 min-6 h), aromatase activity was enhanced by both compounds. Longer time incubation (18 h), however, produced dose-related inhibition. Lindane and BPA had no significant effects on CYP19 mRNA levels. Therefore, lindane and BPA modulate aromatase activity suggesting an interaction with the cytochrome P-450 aromatase. This study highlights the endocrine-modulating properties of lindane and bisphenol-A.

  16. Zoledronic Acid Inhibits Aromatase Activity and Phosphorylation: Potential Mechanism for Additive Zoledronic Acid and Letrozole Drug Interaction

    PubMed Central

    Schech, Amanda J.; Nemieboka, Brandon E.; Brodie, Angela H.

    2012-01-01

    Zoledronic acid (ZA), a bisphosphonate originally indicated for use in osteoporosis, has been reported to exert a direct effect on breast cancer cells, although the mechanism of this effect is currently unknown. Data from the ABCSG-12 and ZO-FAST clinical trials suggest that treatment with the combination of ZA and aromatase inhibitors (AI) result in increased disease free survival in breast cancer patients over AI alone. To determine whether the mechanism of this combination involved inhibition of aromatase, AC-1 cells (MCF-7 human breast cancer cells transfected with an aromatase construct) were treated simultaneously with combinations of ZA and AI letrozole for 72 hours. This combination significantly increased inhibition of aromatase activity of AC-1 cells by compared to letrozole alone. Combination treatment of 1nM letrozole and 1μM and 10μM zoledronic acid resulted in an additive drug interaction on inhibiting cell viability, as measured by MTT assay. Treatment with ZA was found to inhibit phosphorylation of aromatase on serine 473. Zoledronic acid was also shown to be more effective in inhibiting cell viability in aromatase transfected AC-1 cells when compared to inhibition of cell viability observed in non-transfected MCF-7. Estradiol was able to partially rescue the effect of 1μM and 10μM ZA on cell viability following treatment for 72 hours, as shown by a shift to the right in the estradiol dose response curve. In conclusion, these results indicate that the combination of ZA and letrozole results in an additive inhibition of cell viability. Furthermore, ZA alone can inhibit aromatase activity through inhibition of serine phosphorylation events important for aromatase enzymatic activity and contributes to inhibition of cell viability. PMID:22659283

  17. Tributyltin or triphenyltin inhibits aromatase activity in the human granulosa-like tumor cell line KGN.

    PubMed

    Saitoh, M; Yanase, T; Morinaga, H; Tanabe, M; Mu, Y M; Nishi, Y; Nomura, M; Okabe, T; Goto, K; Takayanagi, R; Nawata, H

    2001-11-23

    The superimposition of male sex organs (penis and vas deferens) in a female gastropod, called imposex, is widely attributed to the exposure to tributyltin (TBT) compounds, used world-wide in antifouling paints for ships. It has been hypothesized that the TBT-induced imposex is mediated by an increasing androgen level relative to the estrogen level, namely a decreased conversion of androgens to estrogens (i.e., aromatization). In the present study, we tested this hypothesis by examining the effects of TBT or triphenyltin (TPT) on the aromatase activity in a cultured human granulosa-like tumor cell line, KGN, which was recently established by our group. Treatment with more than 1000 ng/ml TBT compounds was very toxic to the cells and caused immediate cell death within 24 h, while 200 ng/ml was found to cause apoptosis of the cells. Treatment of the KGN cells for more than 48 h with 20 ng/ml TBT or TPT, which is a concentration level reported to cause imposex in marine species, did not affect cell proliferation but significantly suppressed the aromatase activity determined by a [(3)H]H(2)O release assay. Treatment with 20 ng/ml TBT compounds for 7 days also resulted in a reduction of the E2 production from Delta 4-androstenedione stimulated by db-cAMP. The changes in the aromatase activity by TBT compounds were associated with comparable changes in P450arom mRNA assessed by RT-PCR. The luciferase activity of the P450arom promoter II (1 kb) decreased after the addition of 20 ng/ml TBT compounds in transfected KGN cells either in a basic state or in states stimulated by db-cAMP. The Ad4BP-dependent increase in the luciferase activity of P450arom promoter II was also downregulated by such treatments. These results indicate that TBT compounds inhibited the aromatase activity and also decreased the P450arom mRNA level at the transcriptional level in KGN cells. The direct inhibitory effect of TBT compounds on the aromatase activity may therefore partly explain the induction

  18. Inhibition of human placental aromatase activity by hydroxylated polybrominated diphenyl ethers (OH-PBDEs)

    SciTech Connect

    Canton, Rocio F.; Scholten, Deborah E.A.; Marsh, Goeran

    2008-02-15

    Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants in many different polymers, resins and substrates. Due to their widespread production and use, their high binding affinity to particles, and their lipophilic properties, several PBDE congeners can bioaccumulate in the environment. As a result, PBDEs and their hydroxylated metabolites (OH-PBDEs) have been detected in humans and various wildlife samples, such as birds, seals, and whales. Furthermore, certain OH-PBDEs and their methoxylated derivatives (MeO-PBDEs) are natural products in the marine environment. Recently, our laboratory focused on the possible effects on steroidogenesis of PBDEs and OH-PBDEs, e.g. in the human adrenocorticalmore » carcinoma (H295R) cell line indicating that some OH-PBDEs can significantly influence steroidogenic enzymes like CYP19 (aromatase) and CYP17. In the present study, human placental microsomes have been used to study the possible interaction of twenty two OH-PBDEs and MeO-PBDEs with aromatase, the enzyme that mediates the conversion of androgens into estrogens. All OH-PBDE derivates showed significant inhibition of placental aromatase activity with IC{sub 50} values in the low micromolar range, while the MeO-PBDEs did not have any effect on this enzyme activity. Enzyme kinetics studies indicated that two OH-PBDEs, 5-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (5-OH-BDE47) and 6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (6-OH-BDE47), had a mixed-type inhibition of aromatase activity with apparent K{sub i}/K{sub i}' of 7.68/0,02 {mu}M and 5.01/0.04 {mu}M respectively. For comparison, some structurally related compounds, a dihydroxylated polybrominated biphenyl, which is a natural product (2,2'-dihyroxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diOH-BB80)) and its non-bromo derivative were also included in the study. Again inhibition of aromatase activity could be measured, but their potency was significantly less than those observed for the OH-PBDEs. These

  19. Effects of incubation temperature and estrogen exposure on aromatase activity in the brain and gonads of embryonic alligators.

    PubMed Central

    Milnes, Matthew R; Roberts, Robert N; Guillette, Louis J

    2002-01-01

    During embryogenesis, incubation temperature and the hormonal environment influence gonadal differentiation of some reptiles, including all crocodilians. Current evidence suggests that aromatase, the enzyme that converts androgens to estrogens, has a role in sexual differentiation of species that exhibit temperature-dependent sex determination (TSD). During the temperature-sensitive period (TSP) of sex determination, we compared aromatase activity in the brain and gonads of putative male and female alligator embryos to determine if aromatase activity in the embryonic brain could provide the hormonal environment necessary for ovarian development in a TSD species. In addition, we assessed the pattern of aromatase activity in the brain and gonads of embryos treated with estradiol-17beta (E(2)) and incubated at male-producing temperatures to compare enzyme activity in E(2) sex-reversed females to control males and females. This has particular significance regarding wildlife species living in areas contaminated with suspected environmental estrogens. Gonadal aromatase activity remained low during the early stages of the TSP in both sexes and increased late in the TSP only in females. Aromatase activity in the brain increased prior to gonadal differentiation in both sexes. These results suggest that aromatase activity in the brain is not directly responsible for mediating differentiation of the gonad. E(2) exposure at male-producing temperatures resulted in sex-reversed females that had intermediate gonad function and masculinized brain activity. This study indicates the need to examine multiple end points and to determine the persistence of developmental alterations in contaminant-exposed wildlife populations. PMID:12060834

  20. Currently used pesticides and their mixtures affect the function of sex hormone receptors and aromatase enzyme activity

    SciTech Connect

    Kjeldsen, Lisbeth Stigaard; Ghisari, Mandana; Bonefeld-Jørgensen, Eva Cecilie, E-mail: ebj@mil.au.dk

    The endocrine-disrupting potential of pesticides is of health concern, since they are found ubiquitously in the environment and in food items. We investigated in vitro effects on estrogen receptor (ER) and androgen receptor (AR) transactivity, and aromatase enzyme activity, of the following pesticides: 2-methyl-4-chlorophenoxyacetic acid (MCPA), terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb, cypermethrin, tau fluvalinate, malathion and the metabolite ethylene thiourea (ETU). The pesticides were analyzed alone and in selected mixtures. Effects of the pesticides on ER and AR function were assessed in human breast carcinoma MVLN cells and hamster ovary CHO-K1 cells, respectively, using luciferasemore » reporter gene assays. Effects on aromatase enzyme activity were analyzed in human choriocarcinoma JEG-3 cells, employing the classical [{sup 3}H]{sub 2}O method. Five pesticides (terbuthylazine, propiconazole, prothioconazole, cypermethrin and malathion) weakly induced the ER transactivity, and three pesticides (bitertanol, propiconazole and mancozeb) antagonized the AR activity in a concentration-dependent manner. Three pesticides (terbuthylazine, propiconazole and prothioconazole) weakly induced the aromatase activity. In addition, two mixtures, consisting of three pesticides (bitertanol, propiconazole, cypermethrin) and five pesticides (terbuthylazine, bitertanol, propiconazole, cypermethrin, malathion), respectively, induced the ER transactivity and aromatase activity, and additively antagonized the AR transactivity. In conclusion, our data suggest that currently used pesticides possess endocrine-disrupting potential in vitro which can be mediated via ER, AR and aromatase activities. The observed mixture effects emphasize the importance of considering the combined action of pesticides in order to assure proper estimations of related health effect risks

  1. Evidence for an Elevated Aspartate pKa in the Active Site of Human Aromatase*

    PubMed Central

    Di Nardo, Giovanna; Breitner, Maximilian; Bandino, Andrea; Ghosh, Debashis; Jennings, Gareth K.; Hackett, John C.; Gilardi, Gianfranco

    2015-01-01

    Aromatase (CYP19A1), the enzyme that converts androgens to estrogens, is of significant mechanistic and therapeutic interest. Crystal structures and computational studies of this enzyme shed light on the critical role of Asp309 in substrate binding and catalysis. These studies predicted an elevated pKa for Asp309 and proposed that protonation of this residue was required for function. In this study, UV-visible absorption, circular dichroism, resonance Raman spectroscopy, and enzyme kinetics were used to study the impact of pH on aromatase structure and androstenedione binding. Spectroscopic studies demonstrate that androstenedione binding is pH-dependent, whereas, in contrast, the D309N mutant retains its ability to bind to androstenedione across the entire pH range studied. Neither pH nor mutation perturbed the secondary structure or heme environment. The origin of the observed pH dependence was further narrowed to the protonation equilibria of Asp309 with a parallel set of spectroscopic studies using exemestane and anastrozole. Because exemestane interacts with Asp309 based on its co-crystal structure with the enzyme, its binding is pH-dependent. Aromatase binding to anastrozole is pH-independent, consistent with the hypothesis that this ligand exploits a distinct set of interactions in the active site. In summary, we assign the apparent pKa of 8.2 observed for androstenedione binding to the side chain of Asp309. To our knowledge, this work represents the first experimental assignment of a pKa value to a residue in a cytochrome P450. This value is in agreement with theoretical calculations (7.7–8.1) despite the reliance of the computational methods on the conformational snapshots provided by crystal structures. PMID:25425647

  2. Aromatase Activity in Sheepshead Minnow (Cyprinodon variegatus), Exposed to 17B-Trenbolone or 17B-estradiol in a Tier II Two-Generation Test

    EPA Science Inventory

    We tested the hypothesis that endocrine disrupting chemicals (EDCs) that alter fish reproduction will also modulate activity of the steroidogenic enzyme aromatase. There are two distinct isozymes of aromatase that have been characterized in fish, one predominating in brains and a...

  3. Potential effects of environmental contaminants on P450 aromatase activity and DNA damage in swallows from the Rio Grande and Somerville, Texas

    USGS Publications Warehouse

    Sitzlar, M.A.; Mora, M.A.; Fleming, J.G.W.; Bazer, F.W.; Bickham, J.W.; Matson, C.W.

    2009-01-01

    Cliff swallows (Petrochelidon pyrrhonota) and cave swallows (P. fulva) were sampled during the breeding season at several locations in the Rio Grande, Texas, to evaluate the potential effects of environmental contaminants on P450 aromatase activity in brain and gonads and DNA damage in blood cells. The tritiated water-release aromatase assay was used to measure aromatase activity and flow cytometry was used to measure DNA damage in nucleated blood cells. There were no significant differences in brain and gonadal aromatase activities or in estimates of DNA damage (HPCV values) among cave swallow colonies from the Lower Rio Grande Valley (LRGV) and Somerville. However, both brain and gonadal aromatase activities were significantly higher (P < 0.05) in male cliff swallows from Laredo than in those from Somerville. Also, DNA damage estimates were significantly higher (P < 0.05) in cliff swallows (males and females combined) from Laredo than in those from Somerville. Contaminants of current high use in the LRGV, such as atrazine, and some of the highly persistent organochlorines, such as toxaphene and DDE, could be potentially associated with modulation of aromatase activity in avian tissues. Previous studies have indicated possible DNA damage in cliff swallows. We did not observe any differences in aromatase activity or DNA damage in cave swallows that could be associated with contaminant exposure. Also, the differences in aromatase activity and DNA damage between male cliff swallows from Laredo and Somerville could not be explained by contaminants measured at each site in previous studies. Our study provides baseline information on brain and gonadal aromatase activity in swallows that could be useful in future studies. ?? 2008 Springer Science+Business Media, LLC.

  4. Male aromatase-knockout mice exhibit normal levels of activity, anxiety and "depressive-like" symptomatology.

    PubMed

    Dalla, C; Antoniou, K; Papadopoulou-Daifoti, Z; Balthazart, J; Bakker, J

    2005-09-08

    It is well known that estradiol derived from neural aromatization of testosterone plays a crucial role in the development of the male brain and the display of sexual behaviors in adulthood. It was recently found that male aromatase knockout mice (ArKO) deficient in estradiol due to a mutation in the aromatase gene have general deficits in coital behavior and are sexually less motivated. We wondered whether these behavioral deficits of ArKO males could be related to changes in activity, exploration, anxiety and "depressive-like" symptomatology. ArKO and wild type (WT) males were subjected to open field (OF), elevated plus maze (EPM), and forced swim tests (FST), after being exposed or not to chronic mild stress (CMS). CMS was used to evaluate the impact of chronic stressful procedures and to unveil possible differences between genotypes. There was no effect of genotype on OF, EPM and FST behavioral parameters. WT and ArKO mice exposed to CMS or not exhibited the same behavioral profile during these three types of tests. However, all CMS-exposed mice (ArKO and WT) spent less time in the center of the EPM. Additionally, floating duration measured in the FST increased between two tests in both WT and ArKO mice, though that increase was less prominent in mice previously subjected to CMS than in controls. Therefore, both ArKO and WT males displayed the same behavior and had the same response to CMS however CMS exposure slightly modified the behavior displayed by mice of both genotypes in the FST and EPM paradigms. These results show that ArKO males display normal levels of activity, exploration, anxiety and "depressive-like" symptomatology and thus their deficits in sexual behavior are specific in nature and do not result indirectly from other behavioral changes.

  5. Tadalafil modulates aromatase activity and androgen receptor expression in a human osteoblastic cell in vitro model.

    PubMed

    Aversa, A; Fittipaldi, S; Bimonte, V M; Wannenes, F; Papa, V; Francomano, D; Greco, E A; Lenzi, A; Migliaccio, S

    2016-02-01

    Phosphodiesterase type-5 inhibitor (PDE5i) tadalafil administration in men with erectile dysfunction is associated with increased testosterone/estradiol ratio, leading to hypothesize a potential increased effect of androgen action on target tissues. We aimed to characterize, in a cellular model system in vitro, the potential modulation of aromatase and sex steroid hormone receptors upon exposure to tadalafil (TAD). Human osteoblast-like cells SAOS-2 were chosen as an in vitro model system since osteoblasts are target of steroid hormones. Cells were tested for viability upon TAD exposure, which increased cell proliferation. Then, cells were treated with/without TAD for several times to evaluate potential modulation in PDE5, aromatase (ARO), androgen (AR) and estrogen (ER) receptor expression. Osteoblasts express significant levels of both PDE5 mRNA and protein. Exposure of cells to increasing concentrations of TAD (10(-8)-10(-7) M) decreased PDE5 mRNA and protein expression. Also, TAD inhibited ARO mRNA and protein expression leading to an increase in testosterone levels in the supernatants. Interestingly, TAD increased total AR mRNA and protein expression and decreased ERα, with an increased ratio of AR/ER, suggesting preferential androgenic vs estrogenic pathway activation. Our results demonstrate for the first time that TAD decreases ARO expression and increases AR protein expression in human SAOS-2, strongly suggesting a new control of steroid hormones pathway by PDE5i. These findings might represent the first evidence of translational actions of PDE5i on AR, which leads to hypothesize a growing relevance of this molecule in men with prostate cancer long-term treated with TAD for sexual rehabilitation.

  6. Inhibition and induction of aromatase (CYP19) activity by brominated flame retardants in H295R human adrenocortical carcinoma cells.

    PubMed

    Cantón, Rocío F; Sanderson, J Thomas; Letcher, Robert J; Bergman, Ake; van den Berg, Martin

    2005-12-01

    Brominated flame retardants (BFRs) are persistent and ubiquitous chemicals in the environment, and they are found at increasing levels in tissues of wildlife and humans. Previous in vitro studies with the BFR class of polybrominated diphenyl ethers (BDEs) have shown endocrine-disrupting properties. Our study assessed the potential effects of nineteen BDEs, five hydroxylated BDEs (OH-BDEs), one methoxylated BDE (CH(3)O-BDE), tetrabromobisphenol-A (TBBPA), its dibromopropane ether derivative (TBBPA-DBPE), and the brominated phenols/anisols 2,4,6-tribromophenol (TBP), 4-bromophenol (4BP) and 2,4,6-tribromoanisole (TBA) on the catalytic activity of the steroidogenic enzyme aromatase (CYP19) in H295R human adrenocortical carcinoma cells. Effects were studied in the concentration range from 0.5 to 7.5 microM; exposures were for 24 h. Both 6-OH-BDE47 and 6-OH-BDE99 showed an inhibitory effect on aromatase activity at concentrations >2.5 microM and >5 microM, respectively. However, 6-OH-BDE47 also caused a statistically significant increase in cytotoxicity (based on mitochondrial MTT reduction and lactate dehydrogenase-leakage [LDH]) at concentrations >2.5 microM that could explain in part the apparent inhibitory effect on aromatase activity. Compared to 6-OH-BDE47, the methoxy analog (6-CH(3)O-BDE47) did not elicit a cytotoxic effect, whereas significant inhibition of aromatase remained. TBP caused a concentration-dependent induction of aromatase activity between 0.5 and 7.5 microM (with a maximum of 3.8-fold induction at 7.5 microM). This induction was not observed when a OH- group replaced the CH(3)O- group or when bromine atoms adjacent to this OH- group were absent. These in vitro results provide a basis for studies of more detailed structure-activity relationships between these brominated compounds and the modulation of aromatase activity.

  7. Structure-activity relationships and docking studies of synthetic 2-arylindole derivatives determined with aromatase and quinone reductase 1.

    PubMed

    Prior, Allan M; Yu, Xufen; Park, Eun-Jung; Kondratyuk, Tamara P; Lin, Yan; Pezzuto, John M; Sun, Dianqing

    2017-12-15

    In our ongoing effort of discovering anticancer and chemopreventive agents, a series of 2-arylindole derivatives were synthesized and evaluated toward aromatase and quinone reductase 1 (QR1). Biological evaluation revealed that several compounds (e.g., 2d, IC 50  = 1.61 μM; 21, IC 50  = 3.05 μM; and 27, IC 50  = 3.34 μM) showed aromatase inhibitory activity with half maximal inhibitory concentration (IC 50 ) values in the low micromolar concentrations. With regard to the QR1 induction activity, 11 exhibited the highest QR1 induction ratio (IR) with a low concentration to double activity (CD) value (IR = 8.34, CD = 2.75 μM), while 7 showed the most potent CD value of 1.12 μM. A dual acting compound 24 showed aromatase inhibition (IC 50  = 9.00 μM) as well as QR1 induction (CD = 5.76 μM) activities. Computational docking studies using CDOCKER (Discovery Studio 3.5) provided insight in regard to the potential binding modes of 2-arylindoles within the aromatase active site. Predominantly, the 2-arylindoles preferred binding with the 2-aryl group toward a small hydrophobic pocket within the active site. The C-5 electron withdrawing group on indole was predicted to have an important role and formed a hydrogen bond with Ser478 (OH). Alternatively, meta-pyridyl analogs may orient with the pyridyl 3'-nitrogen coordinating with the heme group. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Functional activation of the estrogen receptor-α and aromatase by the HDAC inhibitor, entinostat, sensitizes of ER-negative tumors to letrozole

    PubMed Central

    Sabnis, Gauri J; Goloubeva, Olga; Chumsri, Saranya; Nguyen, Nguyen; Sukumar, Saraswati; Brodie, Angela MH

    2011-01-01

    Approximately 25% of breast cancers do not express the estrogen receptor (ERα) and consequently do not respond to endocrine therapy. In these tumors, ERα repression is often due to epigenetic modifications such as methylation and histone deacetylation. For this reason, we investigated the ability of the histone deacetylase inhibitor entinostat (ENT) to trigger re-expression of ERα and aromatase in breast cancer cells, with the notion that this treatment would restore sensitivity to the aromatase inhibitor letrozole. ENT treatment of tumor cells increased expression of ERα and aromatase along with the enzymatic activity of aromatase, in a dose-dependent manner both in vitro and in vivo. Notably, ERα and aromatase upregulation resulted in sensitization of breast cancer cells to estrogen and letrozole. Tumor growth rate was significantly lower in tumor xenografts following treatment with ENT alone and in combination with letrozole compared to control tumors (p >0.001). ENT plus letrozole also prevented lung colonization and growth of tumor cells with a significant reduction (p>0.03) in both visible and microscopic foci. Our results demonstrate that ENT treatment can be used to restore the letrozole responsiveness of ER-negative tumors. More generally, they provide a strong rationale for immediate clinical evaluation of combinations of histone deacetylase and aromatase inhibitors to treat ER-negative and endocrine-resistant breast cancers. PMID:21245100

  9. Modulation of Aromatase Activity as a Mode of Action for Endocrine Disrupting Chemicals in a Marine Fish

    EPA Science Inventory

    The steroidogenic enzyme aromatase catalyzes the conversion of androgens (androstenedione and testosterone) to estrogens (estrone and estradiol) and therefore plays a central role in reproduction. In contrast to most vertebrates, teleost fish have two distinct forms of aromatase....

  10. Rapid changes in brain aromatase activity in the female quail brain following expression of sexual behaviour.

    PubMed

    de Bournonville, C; Ball, G F; Balthazart, J; Cornil, C A

    2017-11-01

    In male quail, oestrogens produced in the brain (neuro-oestrogens) exert a dual action on male sexual behaviour: they increase sexual motivation within minutes via mechanisms activated at the membrane but facilitate sexual performance by slower, presumably nuclear-initiated, mechanisms. Recent work indicates that neuro-oestrogens are also implicated in the control of female sexual motivation despite the presence of high circulating concentrations of oestrogens of ovarian origin. Interestingly, aromatase activity (AA) in the male brain is regulated in time domains corresponding to the slow "genomic" and faster "nongenomic" modes of action of oestrogens. Furthermore, rapid changes in brain AA are observed in males after sexual interactions with a female. In the present study, we investigated whether similar rapid changes in brain AA are observed in females allowed to interact sexually with males. A significant decrease in AA was observed in the medial preoptic nucleus after interactions that lasted 2, 5 or 10 minutes, although this decrease was no longer significant after 15 minutes of interaction. In the bed nucleus of the stria terminalis, a progressive decline of average AA was observed between 2 and 15 minutes, although it never reached statistical significance. AA in this nucleus was, however, negatively correlated with the sexual receptivity of the female. These data indicate that sexual interactions affect brain AA in females as in males in an anatomically specific manner and suggest that rapid changes in brain oestrogens production could also modulate female sexual behaviour. © 2017 British Society for Neuroendocrinology.

  11. Development of a Novel Tissue Specific Aromatase Activity Regulation Therapeutic Method

    DTIC Science & Technology

    2009-09-01

    Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Estrogen is essential for normal growth and development of the female ...the ovaries and other tissues of the body using an enzyme called aromatase. Once women have reached menopause, the ovaries no longer produce estrogen...Introduction Estrogen is essential for normal growth and development of the female reproductive system, including breast tissue, and lifetime

  12. Aromatase inhibitors in human lung cancer therapy.

    PubMed

    Weinberg, Olga K; Marquez-Garban, Diana C; Fishbein, Michael C; Goodglick, Lee; Garban, Hermes J; Dubinett, Steven M; Pietras, Richard J

    2005-12-15

    Lung cancer is the most common cancer in the world. It is a highly lethal disease in women and men, and new treatments are urgently needed. Previous studies implicated a role of estrogens and estrogen receptors in lung cancer progression, and this steroidal growth-stimulatory pathway may be promoted by tumor expression and activity of aromatase, an estrogen synthase. We found expression of aromatase transcripts and protein in human non-small cell lung cancer (NSCLC) cells using reverse transcription-PCR and Western immunoblots, respectively. Aromatase staining by immunohistochemistry was detected in 86% of archival NSCLC tumor specimens from the clinic. Further, biological activity of aromatase was determined in NSCLC tumors using radiolabeled substrate assays as well as measure of estradiol product using ELISA. Significant activity of aromatase occurred in human NSCLC tumors, with enhanced levels in tumor cells compared with that in nearby normal cells. Lung tumor aromatase activity was inhibited by anastrozole, an aromatase inhibitor, and treatment of tumor cells in vitro with anastrozole led to significant suppression of tumor cell growth. Similarly, among ovariectomized nude mice with A549 lung tumor xenografts, administration of anastrozole by p.o. gavage for 21 days elicited pronounced inhibition of tumor growth in vivo. These findings show that aromatase is present and biologically active in human NSCLCs and that tumor growth can be down-regulated by specific inhibition of aromatase. This work may lead to development of new treatment options for patients afflicted with NSCLC.

  13. Co-Formulants in Glyphosate-Based Herbicides Disrupt Aromatase Activity in Human Cells below Toxic Levels

    PubMed Central

    Defarge, Nicolas; Takács, Eszter; Lozano, Verónica Laura; Mesnage, Robin; Spiroux de Vendômois, Joël; Séralini, Gilles-Eric; Székács, András

    2016-01-01

    Pesticide formulations contain declared active ingredients and co-formulants presented as inert and confidential compounds. We tested the endocrine disruption of co-formulants in six glyphosate-based herbicides (GBH), the most used pesticides worldwide. All co-formulants and formulations were comparably cytotoxic well below the agricultural dilution of 1% (18–2000 times for co-formulants, 8–141 times for formulations), and not the declared active ingredient glyphosate (G) alone. The endocrine-disrupting effects of all these compounds were measured on aromatase activity, a key enzyme in the balance of sex hormones, below the toxicity threshold. Aromatase activity was decreased both by the co-formulants alone (polyethoxylated tallow amine—POEA and alkyl polyglucoside—APG) and by the formulations, from concentrations 800 times lower than the agricultural dilutions; while G exerted an effect only at 1/3 of the agricultural dilution. It was demonstrated for the first time that endocrine disruption by GBH could not only be due to the declared active ingredient but also to co-formulants. These results could explain numerous in vivo results with GBHs not seen with G alone; moreover, they challenge the relevance of the acceptable daily intake (ADI) value for GBHs exposures, currently calculated from toxicity tests of the declared active ingredient alone. PMID:26927151

  14. Effects of chloro-s-triazine herbicides and metabolites on aromatase activity in various human cell lines and on vitellogenin production in male carp hepatocytes.

    PubMed Central

    Sanderson, J T; Letcher, R J; Heneweer, M; Giesy, J P; van den Berg, M

    2001-01-01

    We investigated a potential mechanism for the estrogenic properties of three chloro-s-triazine herbicides and six metabolites in vitro in several cell systems. We determined effects on human aromatase (CYP19), the enzyme that converts androgens to estrogens, in H295R (adrenocortical carcinoma), JEG-3 (placental choriocarcinoma), and MCF-7 (breast cancer) cells; we determined effects on estrogen receptor-mediated induction of vitellogenin in primary hepatocyte cultures of adult male carp (Cyprinus carpio). In addition to atrazine, simazine, and propazine, two metabolites--atrazine-desethyl and atrazine-desisopropyl--induced aromatase activity in H295R cells concentration-dependently (0.3-30 microM) and with potencies similar to those of the parent triazines. After a 24-hr exposure to 30 microM of the triazines, an apparent maximum induction of about 2- to 2.5-fold was achieved. The induction responses were confirmed by similar increases in CYP19 mRNA levels, determined by reverse-transcriptase polymerase chain reaction. In JEG-3 cells, where basal aromatase expression is about 15-fold greater than in H295R cells, the induction responses were similar but less pronounced; aromatase expression in MCF-7 cells was neither detectable nor inducible under our culture conditions. The fully dealkylated metabolite atrazine-desethyl-desisopropyl and the three hydroxylated metabolites (2-OH-atrazine-desethyl, -desisopropyl, and -desethyl-desisopropyl) did not induce aromatase activity. None of the triazine herbicides nor their metabolites induced vitellogenin production in male carp hepatocytes; nor did they antagonize the induction of vitellogenin by 100 nM (EC(50) 17beta-estradiol. These findings together with other reports indicate that the estrogenic effects associated with the triazine herbicides in vivo are not estrogen receptor-mediated, but may be explained partly by their ability to induce aromatase in vitro. PMID:11675267

  15. Differential responsiveness of luteinized human granulosa cells to gonadotropins and insulin-like growth factor I for induction of aromatase activity

    SciTech Connect

    Christman, G.M.; Randolph, J.F. Jr.; Peegel, H.

    1991-06-01

    The objective of this study was to examine the in vitro responsiveness of cultured luteinized human granulosa cells over time to insulin-like growth factor 1 (IGF-1), human follicle-stimulating hormone (FSH), and human chorionic gonadotropin (hCG) for the induction of aromatase activity. Granulosa cells were retrieved from preovulatory follicles in patients undergoing in vitro fertilization. Cells were cultured for a period of 72 hours or 10 days. The ability of hCG, human FSH, and/or IGF-I to induce aromatase activity was assayed by the stereospecific release of tritium from (1B-3H)androstenedione. Short-term cultures (72 hours) demonstrated a marked rise in aromatase activity inmore » response to human FSH and IGF-I, whereas a smaller response to hCG was observed. In contrast, 10-day cultures demonstrated responsiveness predominantly to hCG rather than human FSH for the induction of aromatase activity with no remarkable effect of IGF-I. Luteinized human granulosa cells undergo a transformation from an initial human FSH and IGF-I responsive state to an hCG responsive state in long-term cultures.« less

  16. Development of a new class of aromatase inhibitors: Design, synthesis and inhibitory activity of 3-phenylchroman-4-one (isoflavanone) derivatives

    PubMed Central

    Bonfield, Kevin; Amato, Erica; Bankemper, Tony; Agard, Hannah; Steller, Jeffrey; Keeler, James M.; Roy, David; McCallum, Adam; Paula, Stefan; Ma, Lili

    2014-01-01

    Aromatase (CYP19) catalyzes the aromatization reaction of androgen substrates to estrogens, the last and rate-limiting step in estrogen biosynthesis. Inhibition of aromatase is a new and promising approach to treat hormone-dependent breast cancer. We present here the design and development of isoflavanone derivatives as potential aromatase inhibitors. Structural modifications were performed on the A and B rings of isoflavanones via microwave-assisted, gold-catalyzed annulation reactions of hydroxyaldehydes and alkynes. The in vitro aromatase inhibition of these compounds was determined by fluorescence-based assays utilizing recombinant human aromatase (baculovirus/insect cell-expressed). The compounds 3-(4-phenoxyphenyl)chroman-4-one (1h), 6-methoxy-3-phenylchroman-4-one (2a) and 3-(pyridin-3-yl)chroman-4-one (3b) exhibited potent inhibitory effects against aromatase with IC50 values of 2.4 μM, 0.26 μM and 5.8 μM, respectively. Docking simulations were employed to investigate crucial enzyme/inhibitor interactions such as hydrophobic interactions, hydrogen bonding and heme iron coordination. This report provides useful information on aromatase inhibition and serves as a starting point for the development of new flavonoid aromatase inhibitors. PMID:22444875

  17. [Aromatase activities of endometrial carcinomas and both basic and clinical analyses of endometrial hyperplasia as a premalignant disease].

    PubMed

    Sasaki, H

    1993-08-01

    Paraffin-embedded materials obtained from 117 cases of endometrial hyperplasia and 84 cases of carcinoma were used for measurement of both ki-ras and p53 gene mutation and aromatase (ARO) and TGF-alpha immunostaining. The overall incidence of ki-ras mutations in the hyperplasia specimens (16%) was similar to the incidence detected in carcinomas (18%). None of 117 endometrial hyperplasias were found to have mutations in the p53 gene, whereas mutations were seen in 3 (13.3%) endometrial carcinomas. The intensity of both ARO and TGF-alpha immunostaining was increased in glands of both hyperplasia and carcinoma, and also in the interstitium of carcinoma. The positive sites of both ARO and TGF-alpha were almost the same, with an incidence below 40% in both hyperplasias and carcinomas. The cultured cells of endometrial carcinoma showed aromatase activity below MCF-7 cells, because testosterone was converted to estradiol (E2). TGF-alpha induced cell growth with at an optimal concentration. In HEC-59 cells, TGF-alpha increased both ARO-activity and mRNA. Some promoters on ARO-exon 1 in HEC-59 cells were different from those in BeWo cells. Progesterone inhibited the E2-induced excretion of pre TGF-alpha in endometrial carcinoma cells. These findings suggest that endometrial hyperplasia can be a premalignant condition of carcinoma, and can be initiated by both ki-ras codon 12 mutation and abnormal activity of ARO induced by TGF-alpha. In addition, HEC-59 cells may possess autocrine/paracrine properties involving ARO, E2 and TGF-alpha.

  18. The effects of the standardized extracts of Ginkgo biloba on steroidogenesis pathways and aromatase activity in H295R human adrenocortical carcinoma cells

    PubMed Central

    2016-01-01

    Objectives Aromatase inhibitors that block estrogen synthesis are a proven first-line hormonal therapy for postmenopausal breast cancer. Although it is known that standardized extract of Ginkgo biloba (EGb761) induces anti-carcinogenic effects like the aromatase inhibitors, the effects of EGb761 on steroidogenesis have not been studied yet. Therefore, the effects of EGb761 on steroidogenesis and aromatase activity was studied using a H295R cell model, which was a good in vitro model to predict effects on human adrenal steroidogenesis. Methods Cortisol, aldosterone, testosterone, and 17β-estradiol were evaluated in the H295R cells by competitive enzyme-linked immunospecific assay after exposure to EGb761. Real-time polymerase chain reaction were performed to evaluate effects on critical genes in steroid hormone production, specifically cytochrome P450 (CYP11/ 17/19/21) and the hydroxysteroid dehydrogenases (3β-HSD2 and 17β-HSD1/4). Finally, aromatase activities were measured with a tritiated water-release assay and by western blotting analysis. Results H295R cells exposed to EGb761 (10 and 100 μg/mL) showed a significant decrease in 17β-estradiol and testosterone, but no change in aldosterone or cortisol. Genes (CYP19 and 17β-HSD1) related to the estrogen steroidogenesis were significantly decreased by EGb761. EGb761 treatment of H295R cells resulted in a significant decrease of aromatase activity as measured by the direct and indirect assays. The coding sequence/ Exon PII of CYP19 gene transcript and protein level of CYP19 were significantly decreased by EGb761. Conclusions These results suggest that EGb761 could regulate steroidogenesis-related genes such as CYP19 and 17β-HSD1, and lead to a decrease in 17β-estradiol and testosterone. The present study provides good information on potential therapeutic effects of EGb761 on estrogen dependent breast cancer. PMID:27188280

  19. Perfluorinated chemicals: differential toxicity, inhibition of aromatase activity and alteration of cellular lipids in human placental cells.

    PubMed

    Gorrochategui, Eva; Pérez-Albaladejo, Elisabet; Casas, Josefina; Lacorte, Sílvia; Porte, Cinta

    2014-06-01

    The cytotoxicity of eight perfluorinated chemicals (PFCs), namely, perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorododecanoic acid (PFDoA), perfluorobutanesulfonate (PFBS), perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) was assessed in the human placental choriocarcinoma cell line JEG-3. Only the long chain PFCs--PFOS, PFDoA, PFNA, PFOA--showed significant cytotoxicity in JEG-3 cells with EC50 values in the range of 107 to 647 μM. The observed cytotoxicity was to some extent related to a higher uptake of the longer chain PFCs by cells (PFDoA>PFOS≫PFNA>PFOA>PFHxA). Moreover, this work evidences a high potential of PFOS, PFOA and PFBS to act as aromatase inhibitors in placental cells with IC50s in the range of 57-80 μM, the inhibitory effect of PFBS being particularly important despite the rather low uptake of the compound by cells. Finally, exposure of JEG-3 cells to a mixture of the eight PFCs (0.6 μM each) led to a relative increase (up to 3.4-fold) of several lipid classes, including phosphatidylcholines (PCs), plasmalogen PC and lyso plasmalogen PC, which suggests an interference of PFCs with membrane lipids. Overall, this work highlights the ability of the PFC mixture to alter cellular lipid pattern at concentrations well below those that generate toxicity, and the potential of the short chain PFBS, often considered a safe substitute of PFOS, to significantly inhibit aromatase activity in placental cells. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Potential effect of Olea europea leaves, Sonchus oleraceus leaves and Mangifera indica peel extracts on aromatase activity in human placental microsomes and CYP19A1 expression in MCF-7 cell line: Comparative study.

    PubMed

    Shaban, N Z; Hegazy, W A; Abdel-Rahman, S M; Awed, O M; Khalil, S A

    2016-08-29

    Aromatase inhibitors (AIs) provide novel approaches to the adjuvant therapy for postmenopausal women with estrogen-receptor-positive (ER+) breast cancers. In this study, different plant extracts from Olea europaea leaves (OLE), Sonchus oleraceus L. (SOE) and Mangifera indica peels (MPE) were prepared to identify phytoconstituents and measure antioxidant capacities. The effects of these three extracts on aromatase activity in human placental microsomes were evaluated. Additionally, the effects of these extracts on tissue-specific promoter expression of CYP19A1 gene in cell culture model (MCF-7) were assessed using qRT-PCR. Results showed a concentration-dependent decrease in aromatase activity after treatment with OLE and MPE, whereas, SOE showed a biphasic effect. The differential effects of OLE, SOE and MPE on aromatase expression showed that OLE seems to be the most potent suppressor followed by SOE and then MPE. These findings indicate that OLE has effective inhibitory action on aromatase at both the enzymatic and expression levels, in addition to its cytotoxic effect against MCF-7 cells. Also, MPE may be has the potential to be used as a tissue-specific aromatase inhibitor (selective aromatase inhibitor) and it may be promising to develop a new therapeutic agent against ER+ breast cancer.

  1. EFFECTS OF INCUBATION TEMPERATURE AND ESTROGEN EXPOSURE ON AROMATASE ACTIVITY IN THE BRAIN AND GONADS OF EMBRYONIC ALLIGATORS

    EPA Science Inventory

    During embryogenesis, incubation temperature and the hormonal environment influence gonadal differentiation of some reptiles, including all crocodilians. Current evidence suggests that aromatase, the enzyme that converts androgens to estrogens, has a role in sexual differentiatio...

  2. Brain aromatase: roles in reproduction and neuroprotection.

    PubMed

    Roselli, Charles F

    2007-01-01

    It is well established that aromatization constitutes an essential part of testosterone's signaling pathway in brain and that estrogen metabolites, often together with testosterone, organize and activate masculine neural circuits. This paper summarizes the current understanding regarding the distribution, regulation and function of brain aromatase in mammals. Data from our laboratory are presented that highlight the important function of aromatase in the regulation of androgen feedback sensitivity in non-human primates and the possible role that aromatase plays in determining the brain structure and sexual partner preferences of rams. In addition, new data is presented indicating that the capacity for aromatization in cortical astrocytes is associated with cell survival and may be important for neuroprotection. It is anticipated that a better appreciation of the physiological and pathophysiological functions of aromatase will lead to important clinical insights.

  3. Brain and gonadal aromatase activity and steroid hormone levels in female and polymorphic males of the peacock blenny Salaria pavo.

    PubMed

    Gonçalves, David; Teles, Magda; Alpedrinha, João; Oliveira, Rui F

    2008-11-01

    In the peacock blenny Salaria pavo large males with well-developed secondary sexual characters establish nests and attract females while small "sneaker" males mimic female sexual displays in order to approach the nests of larger males and parasitically fertilize eggs. These alternative reproductive tactics are sequential, as sneakers irreversibly switch into nesting males. This transition involves major morphologic and behavioral changes and is likely to be mediated by hormones. This study focuses on the role of aromatase, an enzyme that catalyses the conversion of androgens into estrogens, in the regulation of male sexual polymorphism in S. pavo. For this, sex steroid plasma levels and aromatase activity (AA) in gonads, whole brain and brain macroareas were determined in sneakers, transitional males (i.e. sneakers undergoing the transition into nesting males), nesting males and females collected in the field. AA was much higher in ovarian tissue than in testicular tissue and accordingly circulating estradiol levels were highest in females. This supports the view that elevated AA and estradiol levels are associated with the development of a functional ovary. Transitional males are in a non-reproductive phase and had underdeveloped testes when compared with sneakers and nesting males. Testicular AA was approximately 10 times higher in transitional males when compared with sneakers and nesting males, suggesting high AA has a suppressive effect on testicular development. Nesting males had significantly higher plasma levels of both testosterone (T) and 11-ketotestosterone when compared with the other male morphs and previous studies demonstrated that these androgens suppress female-like displays in sneakers. In the brain, AA was highest in macroareas presumably containing hypothalamic nuclei traditionally associated with the regulation of reproductive behaviors. Overall, females presented the highest levels of brain AA. In male morphs AA increased from sneakers, to

  4. FOXL2 activates P450 aromatase gene transcription: towards a better characterization of the early steps of mammalian ovarian development.

    PubMed

    Pannetier, Maëlle; Fabre, Stéphane; Batista, Frank; Kocer, Ayhan; Renault, Lauriane; Jolivet, Geneviève; Mandon-Pépin, Béatrice; Cotinot, Corinne; Veitia, Reiner; Pailhoux, Eric

    2006-06-01

    Previous studies have equated FOXL2 as a crucial actor in the ovarian differentiation process in different vertebrate species. Its transcriptional extinction in the polled intersex syndrome (PIS) leads primarily to a drastic decrease of aromatase (CYP19) expression in the first steps of goat ovarian development. In this study, we provide a better characterization of early ovarian development in goat, and we provide experimental evidence demonstrating that FOXL2 represents a direct transcriptional activator of the CYP19 gene through its ovarian-specific promoter 2. Moreover, the ovarian location of FOXL2 and CYP19 proteins, together with their expression profiles in the female gonads, stress the involvement of FOXL2 co-factor(s) for regulating CYP19 transcription. Expressional analyses show that activin-betaA can be considered as a strong candidate for being one of these FOXL2 co-factors. Finally, we discuss evidence for a role of activin and estrogens in somatic and germinal cell proliferation occurring before germ cell meiosis. This period, of 20 days in goat, seems to have no equivalent in mouse. This species-specific difference could explain the phenotype discrepancy observed between XX goat PIS(-/-) and XX mouse Foxl2(-/-).

  5. Assessing differences in sensitivity to aromatase inhibitors among freshwater fish species

    EPA Science Inventory

    There is significant concern regarding potential impairment of fish reproduction associated with exposure to endocrine disrupting chemicals (EDCs). Aromatase is a steroidogenic enzyme involved in the conversion of androgens to estrogens. Inhibition of aromatase activity by exposu...

  6. Natural Products as Aromatase Inhibitors

    PubMed Central

    Balunas, Marcy J.; Su, Bin; Brueggemeier, Robert W.; Kinghorn, A. Douglas

    2010-01-01

    With the clinical success of several synthetic aromatase inhibitors (AIs) in the treatment of postmenopausal estrogen receptor-positive breast cancer, researchers have also been investigating also the potential of natural products as AIs. Natural products from terrestrial and marine organisms provide a chemically diverse array of compounds not always available through current synthetic chemistry techniques. Natural products that have been used traditionally for nutritional or medicinal purposes (e.g., botanical dietary supplements) may also afford AIs with reduced side effects. A thorough review of the literature regarding natural product extracts and secondary metabolites of plant, microbial, and marine origin that have been shown to exhibit aromatase inhibitory activity is presented herein. PMID:18690828

  7. Activity of megestrol acetate in postmenopausal women with advanced breast cancer after nonsteroidal aromatase inhibitor failure: a phase II trial.

    PubMed

    Bines, J; Dienstmann, R; Obadia, R M; Branco, L G P; Quintella, D C; Castro, T M; Camacho, P G; Soares, F A; Costa, M E F

    2014-04-01

    As novel treatments carry substantial price tags and are mostly cost-prohibitive in low- and middle-income countries, there is an urgent need to develop alternatives, such as off-patent drugs. Megestrol acetate (MA) has a longstanding history in the treatment of breast cancer, but recently it is being used less often due to the advent of newer agents. This two-stage phase II trial evaluated the antitumor activity and toxicity of MA in postmenopausal women with hormone-sensitive advanced breast cancer who had experienced disease progression on a third-generation nonsteroidal aromatase inhibitor (NSAI). Eligible patients had metastatic breast cancer treated with a NSAI with at least 6-month progression-free survival (PFS), or relapse after ≥1 year on adjuvant NSAI. Patients received MA at a single daily oral dose of 160 mg. Primary end point was clinical benefit rate (CBR). Forty-eight patients were enrolled. The CBR was 40% [95% confidence interval (CI) 25% to 55%], and the median duration of clinical benefit was 10.0 (95% CI 8.0-14.2) months. The median PFS was 3.9 (95% CI 3.0-4.8) months. The most common grade 3 adverse events were anemia (2%), dyspnea (2%), fatigue (2%), musculoskeletal pain (4%), deep vein thrombosis (10%), and weight gain (2%). This is the first study to prospectively evaluate the efficacy and safety of MA in postmenopausal women with hormone-sensitive disease progressing on a NSAI. MA has demonstrated activity and acceptable tolerability in this setting, and therefore remains a reasonable treatment option in a cost-sensitive environment. These results also provide the background for further evaluation of progestins in the treatment of breast cancer. local trial number, related to the approval by the IRB: CEP 108/06.

  8. Nuclear receptor co-activators and HER-2/neu are upregulated in breast cancer patients during neo-adjuvant treatment with aromatase inhibitors

    PubMed Central

    Flågeng, M Hauglid; Haugan Moi, L L; Dixon, J M; Geisler, J; Lien, E A; Miller, W R; Lønning, P E; Mellgren, G

    2009-01-01

    Background: Acquired resistance to endocrine therapy in breast cancer is poorly understood. Characterisation of the molecular response to aromatase inhibitors in breast cancer tissue may provide important information regarding development of oestrogen hypersensitivity. Methods: We examined the expression levels of nuclear receptor co-regulators, the orphan nuclear receptor liver receptor homologue-1 and HER-2/neu growth factor receptor using real-time RT-PCR before and after 13–16 weeks of primary medical treatment with the aromatase inhibitors anastrozole or letrozole. Results: mRNA expression of the steroid receptor co-activator 1 (SRC-1) and peroxisome-proliferator-activated receptor γ co-activator-1α (PGC-1α) was correlated (P=0.002), and both co-activators increased during treatment in the patient group as a whole (P=0.008 and P=0.032, respectively), as well as in the subgroup of patients achieving an objective treatment response (P=0.002 and P=0.006). Although we recorded no significant change in SRC-3/amplified in breast cancer 1 level, the expression correlated positively to the change of SRC-1 (P=0.002). Notably, we recorded an increase in HER-2/neu levels during therapy in the total patient group (18 out of 26; P=0.016), but in particular among responders (15 out of 21; P=0.008). Conclusion: Our results show an upregulation of co-activator mRNA and HER-2/neu during treatment with aromatase inhibitors. These mechanisms may represent an early adaption of the breast cancer cells to oestrogen deprivation in vivo. PMID:19755984

  9. Effect of Letrozole, a selective aromatase inhibitor, on testicular activities in adult mice: Both in vivo and in vitro study.

    PubMed

    Verma, Rachna; Krishna, Amitabh

    2017-01-15

    The aim of present study was to evaluate the significance of estradiol (E2) in testicular activities and to find out the mechanism by which E2 regulates spermatogenesis in mice. To achieve this, both in vivo and in vitro effect of Letrozole on testis of adult mice was investigated. Letrozole-induced changes in testicular histology, cell proliferation (proliferating cell nuclear antigen; PCNA), cell survival (B cell lymphoma factor-2; Bcl2), apoptotic (cysteine-aspartic proteases; caspase-3), steroidogenic (side chain cleavage; SCC, 3β-hydroxy steroid dehydrogenase enzyme; 3β HSD, steroidogenic acute regulatory protein; StAR, aromatase and luteinizing hormone receptor; LH-R) markers, glucose level, and rate of expression of glucose transporter (GLUT) 8 and insulin receptor (IR) proteins in the testis along with changes in serum E2 and testosterone (T) levels were evaluated. Letrozole acts on testis and caused significant decrease in E2 synthesis, but increase in testosterone level and showed regressive changes in the spermatogenesis. Letrozole-induced changes in various testicular markers were compared with the changes in serum E2 level. The correlation study showed that decreased circulating E2 level may be responsible for decreased insulin receptor (IR) level in the testis. The decreased effects of insulin inhibited the glucose transport in the testis by suppressing GLUT8. The decreased level of testicular glucose may produce less lactate as energy support to developing germ cells consequently resulting in decreased cell proliferation and cell survival, but increased apoptosis. Thus, Letrozole suppresses spermatogenesis by reducing insulin sensitivity and glucose transport in the testis, but significantly increased testosterone level by promoting gonadotrophin release by decreased E2. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Differential Regulation of Aromatase Isoforms and Tissue Responses to Environmental Chemicals in Fish

    EPA Science Inventory

    As in mammals, aromatase plays a basic role in fish reproduction. Unlike most mammals, with only one form of aromatase, fish have two distinct forms. One isoform, P450aromA, predominates in ovaries. Ovarian aromatase activity controls circulating levels of estrogens and is critic...

  11. Aromatase inhibitors and breast cancer prevention.

    PubMed

    Litton, Jennifer Keating; Arun, Banu K; Brown, Powel H; Hortobagyi, Gabriel N

    2012-02-01

    Endocrine therapy with selective estrogen receptor modulators (SERMs) has been the mainstay of breast cancer prevention trials to date. The aromatase inhibitors, which inhibit the final chemical conversion of androgens to estrogens, have shown increased disease-free survival benefit over tamoxifen in patients with primary hormone receptor-positive breast cancer, as well as reducing the risk of developing contralateral breast cancers. The aromatase inhibitors are being actively evaluated as prevention agents for women with a history of ductal carcinoma in situ as well as for women who are considered to be at high risk for developing primary invasive breast cancer. This review evaluates the available prevention data, as evidenced by the decrease in contralateral breast cancers, when aromatase inhibitors are used in the adjuvant setting, as well as the emerging data of the aromatase inhibitors specifically tested in the prevention setting for women at high risk. Exemestane is a viable option for breast cancer prevention. We continue to await further follow-up on exemestane as well as other aromatase inhibitors in the prevention setting for women at high risk of developing breast cancer or with a history of ductal carcinoma in situ.

  12. The use of a unique co-culture model of fetoplacental steroidogenesis as a screening tool for endocrine disruptors: The effects of neonicotinoids on aromatase activity and hormone production.

    PubMed

    Caron-Beaudoin, Elyse; Viau, Rachel; Hudon-Thibeault, Andrée-Anne; Vaillancourt, Cathy; Sanderson, J Thomas

    2017-10-01

    Estrogen biosynthesis during pregnancy is dependent on the collaboration between the fetus producing the androgen precursors, and the placenta expressing the enzyme aromatase (CYP19). Disruption of estrogen production by contaminants may result in serious pregnancy outcomes. We used our recently developed in vitro co-culture model of fetoplacental steroidogenesis to screen the effects of three neonicotinoid insecticides on the catalytic activity of aromatase and the production of steroid hormones. A co-culture of H295R human adrenocortical carcinoma cells with fetal characteristics and BeWo human choriocarcinoma cells which display characteristics of the villous cytotrophoblast was exposed for 24h to various concentrations of three neonicotinoids: thiacloprid, thiamethoxam and imidacloprid. Aromatase catalytic activity was determined in both cell lines using the tritiated water-release assay. Hormone production was measured by ELISA. The three neonicotinoids induced aromatase activity in our fetoplacental co-culture and concordingly, estradiol and estrone production were increased. In contrast, estriol production was strongly inhibited by the neonicotinoids. All three pesticides induced the expression of CYP3A7 in H295R cells, and this induction was reversed by co-treatment of H295R cells with exogenous estriol. CYP3A7 is normally expressed in fetal liver and is a key enzyme involved in estriol synthesis. We suggest that neonicotinoids are metabolized by CYP3A7, thus impeding the 16α-hydroxylation of fetal DHEA(-sulfate), which is normally converted to estriol by placental aromatase. We successfully used the fetoplacental co-culture as a physiologically relevant tool to highlight the potential effects of neonicotinoids on estrogen production, aromatase activity and CYP3A7 expression during pregnancy. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Aromatase in the brain: not just for reproduction anymore.

    PubMed

    Garcia-Segura, L M

    2008-06-01

    Aromatase, the enzyme that synthesises oestrogens from androgen precursors, is expressed in the brain, where it has been classically associated with the regulation of neuroendocrine events and behaviours linked with reproduction. Recent findings, however, have revealed new unexpected roles for brain aromatase, indicating that the enzyme regulates synaptic activity, synaptic plasticity, neurogenesis and the response of neural tissue to injury, and may contribute to control nonreproductive behaviours, mood and cognition. Therefore, the function of brain aromatase is not restricted to the regulation of reproduction as previously thought.

  14. Insulin-like growth factor I enhances the expression of aromatase P450 by inhibiting autophagy.

    PubMed

    Zhang, Bo; Shozu, Makio; Okada, Masahiko; Ishikawa, Hiroshi; Kasai, Tadayuki; Murakami, Kouich; Nomura, Kazuhito; Harada, Nobuhiro; Inoue, Masaki

    2010-10-01

    Aromatase, a key enzyme of estrogen biosynthesis, is transcriptionally regulated by many growth factors. IGF-I enhances aromatase activity in a variety of cells, but the mechanism of action has not been determined. We herein report our finding of a novel mechanism of action for IGF-I. IGF-I enhanced the dexamethasone (DEX)-induced aromatase activity by 30% in serum-starved THP-1 cells. The increase was associated with a corresponding increase in the level of aromatase protein but not with any change in the mRNA level. Metabolic labeling experiments revealed that IGF-I inhibited the degradation of aromatase. We identified pepstatin A as the most effective inhibitor of aromatase degradation by in vitro assay. Using a nontoxic concentration of pepstatin A, we examined IGF-I's action on aromatase distribution in microsomes and lysosomes. In the presence of pepstatin A, DEX caused an increase in the amount of aromatase in both microsomes and lysosomes, and IGF-I attenuated the DEX-induced accumulation of aromatase in lysosomes and, conversely, enhanced its accumulation in the microsomes. The addition of serum abolished the IGF-I-induced changes. The transport from microsome to lysosome was fluorescently traced in cells using a recombinant aromatase. IGF-I selectively reduced the aromatase signal in the lysosomes. Finally, we observed that IGF-I enhanced the aromatase activity by 50% as early as 1 h after treatment; furthermore, rapamycin, an enhancer of autophagy, completely negated the effect of IGF-I on the enzyme. These results indicate that IGF-I enhances aromatase by the inhibition of autophagy.

  15. Aromatase inhibitors in cigarette smoke, tobacco leaves and other plants.

    PubMed

    Osawa, Y; Tochigi, B; Tochigi, M; Ohnishi, S; Watanabe, Y; Bullion, K; Osawa, G; Nakabayashi, Y; Yarborough, C

    1990-01-01

    A chance observation that cigarette smoke interferes with the aromatase assay led us to investigate tobacco leaf and smoke extracts for the presence of aromatase inhibitors. The highest inhibitory activity was found in the basic fraction of cigarette smoke. Further purification of this fraction led to the identification of N-n-octanoylnornicotine. Synthesis and testing of a series of acylated nornicotines and anabasines for their ability to inhibit aromatase showed an interesting correlation of activity with the length of the acyl carbon chain, with maximum activity at C-11. The acylated derivatives showed activity which was significantly greater than that of nicotine and anabasine. In vivo studies in rats indicated that administration of this inhibitor delayed the onset of NMU-induced breast carcinoma and altered the estrus cycle. These in vivo studies suggest that tobacco alkaloid derivatives exert their effects by suppression of the aromatase enzyme system. Toxicity studies indicated relatively low toxicity with LD50 for N-n-octanoylnornicotine = 367 mg/kg body weight. When extracts from thirty five varieties of vegetables, plant leaves, and fruits were analyzed, seventeen showed quantitatively significant aromatase inhibition which was comparable to that of green tobacco leaf, suggesting that naturally occurring substances may affect endocrine function through aromatase inhibition.

  16. Genetics Home Reference: aromatase deficiency

    MedlinePlus

    ... to impaired female sexual development, unusual bone growth, insulin resistance, and other signs and symptoms of aromatase deficiency . In women who are pregnant with an affected fetus, excess androgens in the ...

  17. Insight into the enzyme-inhibitor interactions of the first experimentally determined human aromatase.

    PubMed

    Punetha, Ankita; Shanmugam, Karthi; Sundar, Durai

    2011-04-01

    Aromatase is an important pharmacological target in the anti-cancer therapy as the intratumoral aromatase is the source of local estrogen production in breast cancer tissues. Suppression of estrogen biosynthesis by aromatase inhibition represents an effective approach for the treatment of hormone-sensitive breast cancer. Because of the membrane-bound character and heme-binding instability, no crystal structure of aromatase was reported for a long time, until recently when crystal structure of human placental aromatase cytochrome P450 in complex with androstenedione was deposited in PDB. The present study is towards understanding the structural and functional characteristics of aromatase to address unsolved mysteries about this enzyme and elucidate the exact mode of binding of aromatase inhibitors. We have performed molecular docking simulation with twelve different inhibitors (ligands), which includes four FDA approved drugs; two flavonoids; three herbal compounds and three compounds having biphenyl motif with known IC(50) values into the active site of the human aromatase enzyme. All ligands showed favorable interactions and most of them seemed to interact to hydrophobic amino acids Ile133, Phe134, Phe221, Trp224, Ala306, Val370, Val373, Met374 and Leu477 and hydrophilic Arg115 and neutral Thr310 residues. The elucidation of the actual structure-function relationship of aromatase and the exact binding mode described in this study will be of significant interest as its inhibitors have shown great promise in fighting breast cancer.

  18. Genetics Home Reference: aromatase excess syndrome

    MedlinePlus

    ... Males with aromatase excess syndrome experience breast enlargement (gynecomastia) in late childhood or adolescence. The bones of ... of androgens to estrogen are responsible for the gynecomastia and limited bone growth characteristic of aromatase excess ...

  19. Steroids, aromatase and sex differentiation of the newt Pleurodeles waltl.

    PubMed

    Kuntz, S; Chardard, D; Chesnel, A; Grillier-Vuissoz, I; Flament, S

    2003-01-01

    In the newt Pleurodeles waltl, genetic sex determination obeys female heterogamety (female ZW, male ZZ). In this species as in most of non-mammalian vertebrates, steroid hormones play a key role in sexual differentiation of gonads. In that context, male to female sex reversal can be obtained by treatment of ZZ larvae with estradiol. Male to female sex reversal has also been observed following treatment of ZZ larvae with testosterone, a phenomenon that was called the "paradoxical effect". Female to male sex reversal occurs when ZW larvae are reared at 32 degrees C during a thermosensitive period (TSP) that takes place from stage 42 to stage 54 of development. Since steroids play an important part in sex differentiation, we focussed our studies on the estrogen-producing enzyme aromatase during normal sex differentiation as well as in experimentally induced sex reversal situations. Our results based on treatment with non-aromatizable androgens, aromatase activity measurements and aromatase expression studies demonstrate that aromatase (i) is differentially active in ZZ and ZW larvae, (ii) is involved in the paradoxical effect and (iii) might be a target of temperature. Thus, the gene encoding aromatase might be one of the master genes in the process leading to the differentiation of the gonad in Pleurodeles waltl. Copyright 2003 S. Karger AG, Basel

  20. IGF-I stimulates ERβ and aromatase expression via IGF1R/PI3K/AKT-mediated transcriptional activation in endometriosis.

    PubMed

    Zhou, Yan; Zeng, Cheng; Li, Xin; Wu, Pei-Li; Yin, Ling; Yu, Xiao-Lan; Zhou, Ying-Fang; Xue, Qing

    2016-08-01

    Estrogen receptor beta (ERβ, encoded by ESR2 gene) and cytochrome P450 aromatase (encoded by CYP19A1 gene) play critical roles in endometriosis, and the levels of insulin-like growth factor-I (IGF-I) in the peritoneal fluid are significantly higher in patients with endometriosis compared with those in normal women. However, the effects and mechanisms of IGF-I on ERβ and aromatase expression remain to be fully elucidated. In this study, human endometriotic stromal cells (ESCs) and endometrial cells (EMs) derived from ovarian endometriomas and eutopic endometrial tissues. ESCs were cultured with IGF-I, signal pathway inhibitors, and siRNAs. ERβ and aromatase expression were measured by real-time PCR and Western, respectively. The binding of c-Jun and CREB to the ESR2 and CYP19A1 promoters was assessed by chromatin immunoprecipitation assay. Animal experiments were performed in a xenograft mouse model. Levels of IGF-I mRNA in ESCs were markedly higher than those in EMs. IGF-I upregulated ERβ and aromatase expression in ESCs after stimulation of the IGF1R/PI3K/AKT pathway. Following IGF-I treatment, a marked increase in c-Jun and CREB phosphorylation occurred, enhancing binding to the ESR2 and CYP19A1 promoters. An IGF1R inhibitor in vivo reduced IGF-I-induced endometriosis graft growth and ERβ and aromatase expression. In conclusion, this is the first report to describe a mechanistic analysis of ERβ and aromatase expression regulated by IGF-I in ESCs. Moreover, an IGF1R inhibitor impeded ectopic lesion growth in nude mice. These findings suggest that an inhibitor of IGF1R might have therapeutic potential as an antiendometriotic drug. Level of IGF-I mRNA in ESCs is markedly higher than that in EMs. IGF-I up-regulates ERβ and aromatase expression via IGF1R/PI3K/AKT pathway. C-Jun and CREB are recruited to ESR2 or CYP19A1 promoter by IGF-I stimulation. IGF-1R inhibitors in vivo impede the growth of ectopic lesions in nude mice.

  1. Single or Multiple Access Channels to the CYP450s Active Site? An Answer from Free Energy Simulations of the Human Aromatase Enzyme.

    PubMed

    Magistrato, Alessandra; Sgrignani, Jacopo; Krause, Rolf; Cavalli, Andrea

    2017-05-04

    Cytochromes P450 (CYP450s), in particular, CYP19A1 and CYP17A1, are key clinical targets of breast and prostate anticancer therapies, critical players in drug metabolism, and their overexpression in tumors is associated with drug resistance. In these enzymes, ligand (substrates, drugs) metabolism occurs in deeply buried active sites accessible only via several grueling channels, whose exact biological role remains unclear. Gaining direct insights on the mechanism by which ligands travel in and out is becoming increasingly important given that channels are involved in the modulation of binding/dissociation kinetics and the specificity of ligands toward a CYP450. This has profound implications for enzymatic efficiency and drug efficacy/toxicity. Here, by applying free energy methods, for a cumulative simulation time of 20 μs, we provide detailed atomistic characterization and free energy profiles of the entry/exit routes preferentially followed by a substrate (androstenedione) and a last-generation inhibitor (letrozole) to/from the catalytic site of CYP19A1 (the human aromatase (HA) enzyme), a key clinical target against breast cancer, studied here as prototypical CYP450. Despite the remarkably different size/shape/hydrophobicity of the ligands, two channels appear accessible to their entrance, while only one exit route appears to be preferential. Our study shows that the preferential paths may be conserved among different CYP450s. Moreover, our results highlight that, at least in the case of HA, ligand channeling is associated with large enzyme structural rearrangements. A wise choice of the computational method and very long simulations are, thus, required to obtain fully converged quantitative free energy profiles, which might be used to design novel biocatalysts or next-generation cytochrome inhibitors with an in silico tuned K m .

  2. AOP description: Aromatase inhibition leading to reproductive dysfunction (in fish)

    EPA Science Inventory

    This adverse outcome pathway details the linkage between inhibition of gonadal aromatase activity in females and the adverse effect of reduced cumulative fecundity in repeat-spawning fish species. Cumulative fecundity is the most apical endpoint considered in the OECD 229 Fish Sh...

  3. Aromatase inhibition by synthetic lactones and flavonoids in human placental microsomes and breast fibroblasts - A comparative study

    SciTech Connect

    Meeuwen, J.A. van; Nijmeijer, S.; Mutarapat, T.

    2008-05-01

    Interference of exogenous chemicals with the aromatase enzyme can be useful as a tool to identify chemicals that could act either chemopreventive for hormone-dependent cancer or adverse endocrine disruptive. Aromatase is the key enzyme in the biosynthesis of steroids, as it converts androgens to estrogens. Certain flavonoids, plant derived chemicals, are known catalytic aromatase inhibitors. Various systems are in use to test aromatase inhibitory properties of compounds. Commonly used are microsomes derived from ovary or placental tissue characterized by high aromatase activity. To a lesser extent whole cell systems are used and specifically cell systems that are potential target tissuemore » in breast cancer development. In this study aromatase inhibitory properties of fadrozole, 8-prenylnaringenin and a synthetic lactone (TM-7) were determined in human placental microsomes and in human primary breast fibroblasts. In addition, apigenin, chrysin, naringenin and two synthetic lactones (TM-8 and TM-9) were tested in human microsomes only. Comparison of the aromatase inhibitory potencies of these compounds between the two test systems showed that the measurement of aromatase inhibition in human placental microsomes is a good predictor of aromatase inhibition in human breast fibroblasts.« less

  4. Increase of antitumor activity of cisplatin using agonist of gonadotropin-realising hormone and inhibitor of aromatase on the model of ascites ovarian tumor.

    PubMed

    Tkalia, I G; Vorobyova, L I; Grabovoy, A N; Svintsitsky, V S; Tarasova, T O; Lukyanova, N Y; Todor, I N; Chekhun, V F

    2014-09-01

    To study antitumor activity of triptorelin - agonist of gonadotropin-releasing hormone and exemestane - inhibitor of aromatase in monotherapy and in combination with cisplatin on the model of receptor-positive for estrogens and progesterone malignant ascites transplantable ovarian tumor (TOT), to assess therapeutic pathomorphosis and level of VEGF expression in tumor cells using diffe-rent combinations of cytostatics and hormonal drugs. 72 female Wistar rats, which underwent intraperitoneal transplantation of ascitic TOT, by 5·10(6) cells per animal, have been involved in the study. Rats were divided into 8 groups, 9 rats in each group. Histological study with assessment of therapeutic pathomorphosis in TOT and immunohistochemical study has been carried out. Survival of animals in the studied groups has been evaluated. Among animals treated in regimen of monotherapy, the most pronounced antiangiogenic activity in TOT has been observed on application of hormonal drugs (triptorelin - 39.4 ± 1.9 and exemestane - 33.9 ± 1.4%; р = 0.003), the highest grade of treatment pathomorphosis in TOT has been observed at treatment with cisplatin (11.7%; р = 0.001). Combination of triptorelin and exemestane has amplified antiangiogenic activity in TOT (12.2 ± 0.9%; р = 0.001), but has not significantly changed rates of pathomorphosis (22.1 ± 0.4%; р=0.005) and survival of animals (32.2%; р = 0.007) as compared with the same rates in rats treated with hormonal drugs in monotherapy. Significant correlation between VEGF expression and pathomorphosis has been established (relative part of viable tumor tissue (RPVTT)) in TOT (r = 0.712; р = 0.001), as well as between RPVTT and life-span of animals (r = -0.320; р = 0.007). However, lack of correlation between VEGF expression in cells of TOT and survival of rats has been determined (r = -0.194; р = 0.11). Combination of cytostatic agent with triptorelin or exemestane has demonstrated significantly high rates of therapeutic

  5. Aromatase expression increases the survival and malignancy of estrogen receptor positive breast cancer cells.

    PubMed

    Mukhopadhyay, Keya De; Liu, Zhao; Bandyopadhyay, Abhik; Kirma, Nameer B; Tekmal, Rajeshwar R; Wang, Shui; Sun, Lu-Zhe

    2015-01-01

    In postmenopausal women, local estrogen produced by adipose stromal cells in the breast is believed to support estrogen receptor alpha (ERα) positive breast cancer cell survival and growth. This raises the question of how the ERα positive metastatic breast cancer cells survive after they enter blood and lymph circulation, where estrogen level is very low in postmenopausal women. In this study, we show that the aromatase expression increased when ERα positive breast cancer cells were cultured in suspension. Furthermore, treatment with the aromatase substrate, testosterone, inhibited suspension culture-induced apoptosis whereas an aromatase inhibitor attenuated the effect of testosterone suggesting that suspended circulating ERα positive breast cancer cells may up-regulate intracrine estrogen activity for survival. Consistent with this notion, a moderate level of ectopic aromatase expression rendered a non-tumorigenic ERα positive breast cancer cell line not only tumorigenic but also metastatic in female nude mice without exogenous estrogen supplementation. The increased malignant phenotype was confirmed to be due to aromatase expression as the growth of orthotopic tumors regressed with systemic administration of an aromatase inhibitor. Thus, our study provides experimental evidence that aromatase plays an important role in the survival of metastatic ERα breast cancer cells by suppressing anoikis.

  6. Molecular Action and Clinical Relevance of Aromatase Inhibitors.

    PubMed

    Murphy

    1998-01-01

    -are produced from cholesterol. Inhibiting the enzymes that are involved at earlier steps in the branching pathway of steroidogenesis could have an undesirable impact on the production of other physiologically important hormones such as aldosterone and cortisol. Since aromatase catalyzes the last step in estrogen production, it makes an ideal target for the development of selective and potent inhibitors (Fig. 1). STRUCTURE OF AROMATASE REVEALS SECRETS OF SELECTIVE INHIBITION: Aromatase is a cytochrome P450 enzyme, with both an iron-containing and a steroid-binding site. The substrate, androstenedione, sits in the enzyme's steroid-binding site, that site which otherwise catalyzes the formation of estrogen. From this structural relationship, there are, therefore, two reasonable ways to inhibit aromatase: * by occupying the steroid-binding site of the enzyme with a compound such as formestane (Lentaron®), or * by binding the iron with nitrogen-containing compounds such as aminoglutethimide (Orimeten®), the oldest aromatase inhibitor. AROMATASE INHIBITORS: STEROIDAL AND NON-STEROIDAL: Formestane (Lentaron®) is the only commercially available steroidal compound which inhibits aromatase and must be administered parenterally. Other new aromatase inhibitors such as fadrozole (Afema®) and letrozole (Femara®) are orally active nitrogen-containing compounds that bind the heme iron of aromatase. AMINOGLUTETHIMIDE VERSUS LETROZOLE: OLD VERSUS NEW: Although aminoglutethimide has long been used to treat advanced breast cancer, its aromatase inhibition is not selective. Consequently, aminoglutethimide also binds to and thereby inhibits several other cytochrome P450 enzymes in the steroidogenesis pathway. An ideal aromatase inhibitor would fit the catalytic site of aromatase optimally and would thus interact only with aromatase. The affinity of letrozole (Femara®) for the heme group of aromatase makes it a selective and potent inhibitor (Fig. 2). In fact, studies show

  7. Tissue Physiology and Pathology of Aromatase

    PubMed Central

    Stocco, Carlos

    2011-01-01

    Summary Aromatase is expressed in multiple tissues, indicating a crucial role for locally produced oestrogens in the differentiation, regulation and normal function of several organs and processes. This review is an overview of the role of aromatase in different tissues under normal physiological conditions and its contribution to the development of some oestrogen-related pathologies. PMID:22108547

  8. Aromatase Inhibition in a Transcriptional Network Context

    EPA Science Inventory

    A variety of chemicals in the environment have the potential to inhibit aromatase, an enzyme critical to estrogen synthesis. We examined the responses of female fathead minnow ovaries (FHM, Pimephales promelas) to a model aromatase inhibitor, fadrozole, using a transcriptional ne...

  9. Inhibitory effect of luteolin on estrogen biosynthesis in human ovarian granulosa cells by suppression of aromatase (CYP19).

    PubMed

    Lu, Dan-feng; Yang, Li-juan; Wang, Fei; Zhang, Guo-lin

    2012-08-29

    Inhibition of aromatase, the key enzyme in estrogen biosynthesis, is an important strategy in the treatment of breast cancer. Several dietary flavonoids show aromatase inhibitory activity, but their tissue specificity and mechanism remain unclear. This study found that the dietary flavonoid luteolin potently inhibited estrogen biosynthesis in a dose- and time-dependent manner in KGN cells derived from human ovarian granulosa cells, the major source of estrogens in premenopausal women. Luteolin decreased aromatase mRNA and protein expression in KGN cells. Luteolin also promoted aromatase protein degradation and inhibited estrogen biosynthesis in aromatase-expressing HEK293A cells, but had no effect on recombinant expressed aromatase. Estrogen biosynthesis in KGN cells was inhibited with differing potencies by extracts of onion and bird chili and by four other dietary flavonoids: kaempferol, quercetin, myricetin, and isorhamnetin. The present study suggests that luteolin inhibits estrogen biosynthesis by decreasing aromatase expression and destabilizing aromatase protein, and it warrants further investigation as a potential treatment for estrogen-dependent cancers.

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

    SciTech Connect

    Ghosh, Debashis; Griswold, Jennifer; Erman, Mary

    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 hallmarkmore » 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.« less

  11. Identification of endocrine disrupting chemicals acting on human aromatase.

    PubMed

    Baravalle, Roberta; Ciaramella, Alberto; Baj, Francesca; Di Nardo, Giovanna; Gilardi, Gianfranco

    2018-01-01

    Human aromatase is the cytochrome P450 catalysing the conversion of androgens into estrogens playing a key role in the endocrine system. Due to this role, it is likely to be a target of the so-called endocrine disrupting chemicals, a series of compounds able to interfere with the hormone system with toxic effects. If on one side the toxicity of some compounds such as bisphenol A is well known, on the other side the toxic concentrations of such compounds as well as the effect of the many other molecules that are in contact with us in everyday life still need a deep investigation. The availability of biological assays able to detect the interaction of chemicals with key molecular targets of the endocrine system represents a possible solution to identify potential endocrine disrupting chemicals. Here the so-called alkali assay previously developed in our laboratory is applied to test the effect of different compounds on the activity of human aromatase. The assay is based on the detection of the alkali product that forms upon strong alkali treatment of the NADP + released upon enzyme turnover. Here it is applied on human aromatase and validated using anastrozole and sildenafil as known aromatase inhibitors. Out of the small library of compounds tested, resveratrol and ketoconazole resulted to inhibit aromatase activity, while bisphenol A and nicotine were found to exert an inhibitory effect at relatively high concentrations (100μM), and other molecules such as lindane and four plasticizers did not show any significant effect. These data are confirmed by quantification of the product estrone in the same reaction mixtures through ELISA. Overall, the results show that the alkali assay is suitable to screen for molecules that interfere with aromatase activity. As a consequence it can also be applied to other molecular targets of EDCs that use NAD(P)H for catalysis in a high throughput format for the fast screening of many different compounds as endocrine disrupting

  12. Aromatase Inhibitors and Bone Loss

    PubMed Central

    PEREZ, EDITH A.; M., Serene; Durling, Frances C.; WEILBAECHER, KATHERINE

    2009-01-01

    The aromatase inhibitors (AIs) anastrozole (Arimidex), letrozole (Femara), and exemestane (Aromasin) are significantly more effective than the selective estrogen-receptor modulator (SERM) tamoxifen in preventing recurrence in estrogen receptor–positive early breast cancer. Aromatase inhibitors are likely to replace SERMs as first-line adjuvant therapy for many patients. However, AIs are associated with significantly more osteoporotic fractures and greater bone mineral loss. As antiresorptive agents, oral and intravenous bisphosphonates such as alendronate (Fosamax), risedronate (Actonel), ibandronate (Boniva), pamidronate (Aredia), and zoledronic acid (Zometa) have efficacy in preventing postmenopausal osteoporosis, cancer treatment–related bone loss, or skeletal complications of metastatic disease. Clinical practice guidelines recommend baseline and annual follow-up bone density monitoring for all patients initiating AI therapy. Bisphosphonate therapy should be prescribed for patients with osteoporosis (T score < −2.5) and considered on an individual basis for those with osteopenia (T score < −1). Modifiable lifestyle behaviors including adequate calcium and vitamin D intake, weight-bearing exercise, and smoking cessation should be addressed. Adverse events associated with bisphosphonates include gastrointestinal toxicity, renal toxicity, and osteonecrosis of the jaw. These safety concerns should be balanced with the potential of bisphosphonates to minimize or prevent the debilitating effects of AI-associated bone loss in patients with early, hormone receptor–positive breast cancer. PMID:16986348

  13. Sex change strategy and the aromatase genes.

    PubMed

    Gardner, L; Anderson, T; Place, A R; Dixon, B; Elizur, A

    2005-04-01

    Sequential hermaphroditism is a common reproductive strategy in many teleosts. Steroid production is known to mediate both the natural and induced sex change, yet beyond this the physiology directing this process has received little attention. Cytochrome P450 aromatase is a key enzyme in the hormonal pathway catalysing the conversion of sex steroids, androgens to oestrogens, and thus is highly relevant to the process of sex change. This study reports the isolation of cDNA sequences for aromatase isoforms CYP19A1 and CYP19A2 from teleost species representing three forms of sexual hermaphroditism: Lates calcarifer (protandry), Cromileptes altivelis (protogyny), and Gobiodon histrio (bi-directional). Deduced amino acid analysis of these isoforms with other reported isoforms from gonochoristic (single sex) teleosts revealed 56-95% identity within the same isoform while only 48-65% identity between isoforms irrespective of species and sexual strategy. Phylogenetic analysis supported this result separating sequences into isoform exclusive clades in spite of species apparent evolutionary distance. Furthermore, this study isolates 5' flanking regions of all above genes and describes putative cis-acting elements therein. Elements identified include steroidogenic factor 1 binding site (SF-1), oestrogen response element (ERE), progesterone response element (PRE), androgen response element (ARE), glucocorticoid response elements (GRE), peroxisome proliferator-activated receptor alpha/retinoid X receptor alpha heterodimer responsive element (PPARalpha/RXRalpha), nuclear factor kappabeta (NF-kappabeta), SOX 5, SOX 9, and Wilms tumor suppressor (WTI). A hypothetical in vivo model was constructed for both isoforms highlighting potential roles of these putative cis-acting elements with reference to normal function and sexual hermaphroditism.

  14. Role of P-450 aromatase in sex determination of the diamondback terrapin, Malaclemys terrapin.

    PubMed

    Jeyasuria, P; Roosenburg, W M; Place, A R

    1994-09-15

    Sex determination in the diamondback terrapin, Malaclemys terrapin, is temperature-dependent. Eggs incubated at 31 degrees C, and above, hatch in approximately 45 days as females. Eggs incubated below 27 degrees C hatch in about 60 days as males. Sex is not reversible after hatching. Nest temperatures in the wild can be as low as 20 degrees C and as high as 37 degrees C with as much as a 10 degrees C diel cycle. The shortest incubation time measured in nature was 56 days and the longest approaching 120 days. Nests in our study site produced predominantly (> 95%) male hatchlings. Treatment of developing embryos with estrogen produces females at male producing temperatures while treatment with fadrozole (a nonsteroidal aromatase inhibitor) induces partial male-like gonads. Treatment with a steroidal aromatase inhibitor (4-hydroxyandrostenedione, 4-OHA) had no effect on sex determination. Both fadrozole and 4-OHA are potent competitive inhibitors (Ki approximately 40-50 nM) for terrapin in vitro aromatase activity. These findings are consistent with aromatase expression being a key step in sex determination of terrapins. We have cloned a partial single copy P-450 aromatase from the terrapin using a cDNA library constructed from ovarian mRNA. This partial clone is highly homologous to other vertebrate aromatases.

  15. ALTERATIONS IN THE TRANSCRIPTOME AND PROTEOME OF ZEBRAFISH (DANIO RERIO) EXPOSED TO FADROZOLE, A MODEL AROMATASE INHIBITOR

    EPA Science Inventory

    Fadrozole is a reversible, competitive inhibitor of aromatase activity and therefore an endocrine-disrupting compound (EDC) that disrupts steroidogenesis by inhibiting the conversion of testosterone to 172-estradiol. While fadrozole is a therapeutic drug with generally no enviro...

  16. Regulation of aromatase expression in the anterior amygdala of the developing mouse brain depends on ERβ and sex chromosome complement.

    PubMed

    Cisternas, Carla Daniela; Cabrera Zapata, Lucas Ezequiel; Arevalo, María Angeles; Garcia-Segura, Luis Miguel; Cambiasso, María Julia

    2017-07-13

    During development sex differences in aromatase expression in limbic regions of mouse brain depend on sex chromosome factors. Genes on the sex chromosomes may affect the hormonal regulation of aromatase expression and this study was undertaken to explore that possibility. Male E15 anterior amygdala neuronal cultures expressed higher levels of aromatase (mRNA and protein) than female cultures. Furthermore, treatment with oestradiol (E2) or dihydrotestosterone (DHT) increased Cyp19a1 expression and aromatase protein levels only in female neuronal cultures. The effect of E2 on aromatase expression was not imitated by oestrogen receptor (ER) α agonist PPT or the GPER agonist G1, but it was fully reproduced by DPN, a specific ligand of ERβ. By contrast, the effect of DHT on aromatase expression was not blocked by the anti-androgen flutamide, but completely abrogated by the ERβ antagonist PHTPP. Experiments using the four core genotype model showed a sex chromosome effect in ERβ expression (XY > XX) and regulation by E2 or DHT (only XX respond) in amygdala neurons. In conclusion, sex chromosome complement governs the hormonal regulation of aromatase expression through activation of ERβ in developing mouse brain.

  17. Estrogen receptor-independent catechol estrogen binding activity: protein binding studies in wild-type, Estrogen receptor-alpha KO, and aromatase KO mice tissues.

    PubMed

    Philips, Brian J; Ansell, Pete J; Newton, Leslie G; Harada, Nobuhiro; Honda, Shin-Ichiro; Ganjam, Venkataseshu K; Rottinghaus, George E; Welshons, Wade V; Lubahn, Dennis B

    2004-06-01

    Primary evidence for novel estrogen signaling pathways is based upon well-documented estrogenic responses not inhibited by estrogen receptor antagonists. In addition to 17beta-E2, the catechol estrogen 4-hydroxyestradiol (4OHE2) has been shown to elicit biological responses independent of classical estrogen receptors in estrogen receptor-alpha knockout (ERalphaKO) mice. Consequently, our research was designed to biochemically characterize the protein(s) that could be mediating the biological effects of catechol estrogens using enzymatically synthesized, radiolabeled 4-hydroxyestrone (4OHE1) and 4OHE2. Scatchard analyses identified a single class of high-affinity (K(d) approximately 1.6 nM), saturable cytosolic binding sites in several ERalphaKO estrogen-responsive tissues. Specific catechol estrogen binding was competitively inhibited by unlabeled catechol estrogens, but not by 17beta-E2 or the estrogen receptor antagonist ICI 182,780. Tissue distribution studies indicated significant binding differences both within and among various tissues in wild-type, ERalphaKO, and aromatase knockout female mice. Ligand metabolism experiments revealed extensive metabolism of labeled catechol estrogen, suggesting that catechol estrogen metabolites were responsible for the specific binding. Collectively, our data provide compelling evidence for the interaction of catechol estrogen metabolites with a novel binding protein that exhibits high affinity, specificity, and selective tissue distribution. The extensive biochemical characterization of this binding protein indicates that this protein may be a receptor, and thus may mediate ERalpha/beta-independent effects of catechol estrogens and their metabolites.

  18. Molecular docking and QSAR study on steroidal compounds as aromatase inhibitors.

    PubMed

    Dai, Yujie; Wang, Qiang; Zhang, Xiuli; Jia, Shiru; Zheng, Heng; Feng, Dacheng; Yu, Peng

    2010-12-01

    In order to develop more potent, selective and less toxic steroidal aromatase (AR) inhibitors, molecular docking, 2D and 3D hybrid quantitative structure-activity relationship (QSAR) study have been conducted using topological, molecular shape, spatial, structural and thermodynamic descriptors on 32 steroidal compounds. The molecular docking study shows that one or more hydrogen bonds with MET374 are one of the essential requirements for the optimum binding of ligands. The QSAR model obtained indicates that the aromatase inhibitory activity can be enhanced by increasing SIC, SC_3_C, Jurs_WNSA_1, Jurs_WPSA_1 and decreasing CDOCKER interaction energy (ECD), IAC_Total and Shadow_XZfrac. The predicted results shows that this model has a comparatively good predictive power which can be used in prediction of activity of new steroidal aromatase inhibitors. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  19. Aromatase and estrogen receptors in male reproduction.

    PubMed

    Carreau, Serge; Delalande, Christelle; Silandre, Dorothée; Bourguiba, Sonia; Lambard, Sophie

    2006-02-26

    Aromatase is a terminal enzyme which transforms irreversibly androgens into estrogens and it is present in the endoplasmic reticulum of numerous tissues. We have demonstrated that mature rat germ cells express a functional aromatase with a production of estrogens equivalent to that of Leydig cells. In humans in addition to Leydig cells, we have shown the presence of aromatase in ejaculated spermatozoa and in immature germ cells. In most tissues, high affinity estrogen receptors, ERalpha and/or ERbeta, mediate the role of estrogens. Indeed, in human spermatozoa, we have successfully amplified ERbeta mRNA but the protein was not detectable. Using ERalpha antibody we have detected two proteins in human immature germ cells: one at the expected size 66 kDa and another at 46 kDa likely corresponding to the ERalpha isoform lacking exon 1. In spermatozoa only the 46 kDa isoform was present, and we suggest that it may be located on the membrane. In addition, in men genetically deficient in aromatase, it is reported that alterations of spermatogenesis occur both in terms of the number and motility of spermatozoa. All together, these observations suggest that endogenous estrogens are important in male reproduction.

  20. Aromatase mRNA in the brain of adult green anole lizards: effects of sex and season.

    PubMed

    Cohen, R E; Wade, J

    2011-03-01

    Neural testosterone metabolism, particularly the synthesis of oestradiol (E(2)) via the aromatase enzyme, is important for sexual behaviours in many vertebrates. In green anole lizards, E(2) metabolised from testosterone facilitates female receptivity and increases sexual motivation in males. Testosterone treatment increases aromatase activity in the whole brain homogenates of gonadectomised male, but not female, anoles, which is an effect limited to the breeding season (BS). To investigate the potential for local effects of this enzyme in reproductive behaviour, we used in situ hybridisation for aromatase mRNA to examine expression during the BS and nonbreeding season (NBS) in areas of the brain that control male sexual behaviours [preoptic area (POA) and amygdala (AMY)], as well as one regulating female reproductive behaviours ventromedial hypothalamus (VMH). Males had a greater total number of aromatase-expressing cells in the POA than females, and the density of aromatase-expressing cells (number per unit volume) was greater in the VMH and AMY of females. This density was also higher during the BS than NBS in the POA. Expression of aromatase in the AMY appeared to be lateralised because trends were detected for the left side to have more total cells and more cells per unit volume than the right. These results suggest that, similar to other vertebrates, regional aromatisation of testosterone may be important for the control of sex-specific reproductive behaviours. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.

  1. Dry eye syndrome in aromatase inhibitor users.

    PubMed

    Turaka, Kiran; Nottage, Jennifer M; Hammersmith, Kristin M; Nagra, Parveen K; Rapuano, Christopher J

    2013-04-01

    Aromatase inhibitors are frequently used as an adjuvant therapy in the treatment of breast cancer. We observed that several patients taking aromatase inhibitors presented with severe dry eye symptoms, and we investigated whether there is a relationship between aromatase inhibitors and dry eyes in these patients. Retrospective chart review. Forty-one women. A computerized search of health records was performed to identify patients using anastrazole, letrozole and exemestane seen by the Cornea Service from August 2008 to March 2011. The results were compared with age-matched controls. Ocular surface changes among aromatase inhibitors users. Of the 41 women, 39 were Caucasians. Thirty-nine patients had breast cancer (95%), one patient had ovarian cancer (2.5%) and one had an unknown primary cancer. Mean age was 68 ± 11.3 years (range 47-95). Most common presenting symptoms were blurred vision in 28 (68%) patients, irritation/foreign body sensation in 12 (29%) patients, redness in 9 (22%) patients, tearing in 6 (22%) patients and photosensitivity in 2 (5%) patients. Mean Schirmer's test measurement was 11 ± 5.8 mm (range 0.5-20 mm). Blepharitis was noted in 68 of 82 eyes (73%), decreased or poor tear function in 24 eyes (29%), conjunctival injection in 18 eyes (22%) and superficial punctate keratitis in 12 eyes (29%). Among an age-matched population (45-95 years), dry eye syndrome was found in only 9.5% of patients. Because the prevalence of ocular surface disease signs and symptoms appears to be higher in study group than control patients, aromatase inhibitors might be a contributing factor to the dry eye symptoms. © 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

  2. Sex Amphibian, Xenopus tropicalis, following Larval Exposure to an Aromatase Inhibitor

    EPA Science Inventory

    Aromatase is a steroidogenic enzyme that catalyzes the conversion of androgens to estrogens in vertebrates. Modulation of this enzyme’s activity by xenobiotic exposure has been shown to adversely affect gonadal differentiation in a number of diverse species. We hypothesized tha...

  3. Aromatase inhibitor (anastrozole) affects growth of endometrioma cells in culture.

    PubMed

    Badawy, Shawky Z A; Brown, Shereene; Kaufman, Lydia; Wojtowycz, Martha A

    2015-05-01

    To study the effects of aromatase inhibitor (anastrozole) on the growth and estradiol secretion of endometrioma cells in culture. Endometrioma cells are grown in vitro until maximum growth before used in this study. This was done in the research laboratory for tissue culture, in an academic hospital. Testosterone at a concentration of 10 μg/mL was added as a substrate for the intracellular aromatase. In addition, aromatase inhibitor was added at a concentration of 200 and 300 μg/mL. The effect on cell growth and estradiol secretion is evaluated using Student's t-test. The use of testosterone increased estradiol secretion by endometrioma cells in culture. The use of aromatase inhibitor significantly inhibited the growth of endometrioma cells, and estradiol secretion. Aromatase inhibitor (anastrozole) may be an effective treatment for endometriosis due to inhibition of cellular aromatase. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Of mice and men: the evolving phenotype of aromatase deficiency.

    PubMed

    Jones, Margaret E E; Boon, Wah Chin; Proietto, Joseph; Simpson, Evan R

    2006-03-01

    We are rapidly becoming aware of the importance of estrogen in maintaining virtually all facets of male health. In order for estrogens to be synthesized endogenously, the enzyme responsible for their synthesis from androgens, aromatase, must be functional. The seven known men in whom aromatase is nonfunctional all have a mutation in either exon V or IX of the CYP19 gene, which encodes aromatase. Collectively, these men are reported to have undetectable estrogen; normal to high levels of testosterone and gonadotropins; tall stature with delayed skeletal maturation and epiphyseal closure; osteoporosis; impaired lipid and insulin metabolism; and impaired reproductive function. The aromatase knockout mouse presents with a phenotype that is similar in many aspects and provides a valuable tool with which to examine and manipulate the actions of estrogen. By studying the naturally occurring aromatase-deficient humans, together with studies of the aromatase-knockout mouse, we are expanding our understanding of the essential role of estrogen in male physiology.

  5. Estrogenic encounters: How interactions between aromatase and the environment modulate aggression

    PubMed Central

    Trainor, Brian C.; Kyomen, Helen H.; Marler, Catherine A.

    2007-01-01

    Initial investigations into the mechanistic basis of aggression focused on the role of testosterone (T) and a variety of studies on non-human animals found that elevated T levels promote aggression. However, many correlational studies have not detected a significant association between aggression and peripheral T levels. One reason for this inconsistency may be due to differential metabolism of T within the brain, in particular, the conversion of T to estrogen by aromatase. Thus, differences in aromatase enzyme activity, estrogen receptor expression, and related cofactors may have important effects on how steroids affect aggressive behavior. Hormone manipulation studies conducted in a wide variety of species indicate that estrogens modulate aggression. There is also growing evidence that social experience has important effects on the production of estrogen within the brain, and some cases can not be explained by androgenic regulation of aromatase. Such changes in central aromatase activity may play an important role in determining how social experiences affect the probability of whether an individual engages in aggressive behavior. Although studies have been conducted in many taxa, there has been relatively little integration between literatures examining aggression in different species. In this review, we compare and contrast studies examining aggression in birds, mammals, and humans. By taking an integrative approach to our review, we consider mechanisms that could explain species differences in how estrogen modulates aggression. PMID:16376420

  6. Inflammation, dysregulated metabolism and aromatase in obesity and breast cancer.

    PubMed

    Zahid, Heba; Simpson, Evan R; Brown, Kristy A

    2016-12-01

    Obesity is associated with an increased risk of estrogen-dependent breast cancer after menopause. Adipose tissue undergoes important changes in obesity due to excess storage of lipids, leading to adipocyte cell death and the recruitment of macrophages. The resultant state of chronic low-grade inflammation is associated with the activation of NFkB signaling and elevated levels of aromatase, the rate-limiting enzyme in estrogen biosynthesis. This occurs not only in the visceral and subcutaneous fat, but also in the breast fat. The regulation of aromatase in the breast adipose stromal cell in response to inflammatory mediators is under the control of complex signaling pathways, including metabolic pathways involving LKB1/AMPK, p53, HIF1α and PKM2. Interventions aimed at modifying weight, including diet and exercise, are associated with changes in adipose tissue inflammation and estrogen production that are likely to impact breast cancer risk. This review will present an overview of these topics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Modelling inhibition of avian aromatase by azole pesticides.

    PubMed

    Saxena, A K; Devillers, J; Bhunia, S S; Bro, E

    2015-01-01

    The potential effects of pesticides and their metabolites on the endocrine system are of major concern to wildlife and human health. In this context, the azole pesticides have earned special attention due to their cytochrome P450 aromatase inhibition potential. Cytochrome P450 aromatase (CYP19) catalyses the conversion of androstenedione and testosterone into oestrone and oestradiol, respectively. Thus, aromatase modulates the oestrogenic balance essential not only for females, but also for male physiology, including gonadal function. Its inhibition affects reproductive organs, fertility and sexual behaviour in humans and wildlife species. Several studies have shown that azole pesticides are able to inhibit human and fish aromatases but the information on birds is lacking. Consequently, it appeared to be of interest to estimate the aromatase inhibition of azoles in three different avian species, namely Gallus gallus, Coturnix coturnix japonica and Taeniopygia guttata. In the absence of the crystal structure of the aromatase enzyme in these bird species, homology models for the individual avian species were constructed using the crystal structure of human aromatase (hAr) (pdb: 3EQM) that showed high sequence similarity for G. gallus (82.0%), T. guttata (81.9%) and C. japonica (81.2%). A homology model with Oncorhynchus mykiss (81.9%) was also designed for comparison purpose. The homology-modelled aromatase for each avian and fish species and crystal structure of human aromatase were selected for docking 46 structurally diverse azoles and related compounds. We showed that the docking behaviour of the chemicals on the different aromatases was broadly the same. We also demonstrated that there was an acceptable level of correlation between the binding score values and the available aromatase inhibition data. This means that the homology models derived on bird and fish species can be used to approximate the potential inhibitory effects of azoles on their aromatase.

  8. Cytotoxic effects and aromatase inhibition by xenobiotic endocrine disrupters alone and in combination.

    PubMed

    Benachour, Nora; Moslemi, Safa; Sipahutar, Herbert; Seralini, Gilles-Eric

    2007-07-15

    Xenobiotics may cause long-term adverse effects in humans, especially at the embryonic level, raising questions about their levels of exposure, combined effects, and crucial endpoints. We are interested in the possible interactions between xenobiotic endocrine disrupters, cellular viability and androgen metabolism. Accordingly, we tested aroclor 1254 (A1254), atrazine (AZ), o,p'-DDT, vinclozolin (VZ), p,p'-DDE, bisphenol A (BPA), chlordecone (CD), nonylphenol (NP), tributylin oxide (TBTO), and diethylstilbestrol (DES) for cellular toxicity against human embryonic 293 cells, and activity against cellular aromatase, but also on placental microsomes and on the purified equine enzyme. Cellular viability was affected in 24 h by all the xenobiotics with a threshold at 50 microM (except for TBTO and DES, 10 microM threshold), and aromatase was inhibited at non-toxic doses. In combination synergism was observed reducing the threshold values of toxicity to 4-10 microM, and aromatase activity by 50% in some cases. In placental microsomes the most active xenobiotics rapidly inhibited microsomal aromatase in a manner independent of NADPH metabolism. Prolonged exposures to low doses in cells generally amplified by 50 times aromatase inhibition. These xenobiotics may act by inhibition of the active site or by allosteric effects on the enzyme. Bioaccumulation is a feature of some xenobiotics, especially chlordecone, DDT and DDE, and low level chronic exposures can also affect cell signaling mechanisms. This new information about the mechanism of action of these xenobiotics will assist in improved molecular design with a view to providing safer compounds for use in the (human) environment.

  9. Studies on non-steroidal inhibitors of aromatase enzyme; 4-(aryl/heteroaryl)-2-(pyrimidin-2-yl)thiazole derivatives.

    PubMed

    Sahin, Zafer; Ertas, Merve; Berk, Barkın; Biltekin, Sevde Nur; Yurttas, Leyla; Demirayak, Seref

    2018-05-01

    Steroidal and non-steroidal aromatase inhibitors target the suppression of estrogen biosynthesis in the treatment of breast cancer. Researchers have increasingly focused on developing non-steroidal derivatives for their potential clinical use avoiding steroidal side-effects. Non-steroidal derivatives generally have planar aromatic structures attached to the azole ring system. One part of this ring system comprises functional groups that inhibit aromatization through the coordination of the haem group of the aromatase enzyme. Replacement of the triazole ring system and development of aromatic/cyclic structures of the side chain can increase selectivity over aromatase enzyme inhibition. In this study, 4-(aryl/heteroaryl)-2-(pyrimidin-2-yl)thiazole derivatives were synthesized and physical analyses and structural determination studies were performed. The IC 50 values were determined by a fluorescence-based aromatase inhibition assay and compound 1 (4-(2-hydroxyphenyl)-2-(pyrimidine-2-yl)thiazole) were found potent inhibitor of enzyme (IC 50 :0.42 nM). Then, their antiproliferative activity over MCF-7 and HEK-293 cell lines was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Compounds 1, 7, 8, 13, 15, 18, 21 were active against MCF-7 breast cancer cells. Lastly, a series of docking experiments were undertaken to analyze the crystal structure of human placental aromatase and identify the possible interactions between the most active structure and the active site. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Gonadal expression of Sf1 and aromatase during sex determination in the red-eared slider turtle (Trachemys scripta), a reptile with temperature-dependent sex determination.

    PubMed

    Ramsey, Mary; Shoemaker, Christina; Crews, David

    2007-12-01

    Many egg-laying reptiles have temperature-dependent sex determination (TSD), where the offspring sex is determined by incubation temperature during a temperature-sensitive period (TSP) in the middle third of development. The underlying mechanism transducing a temperature cue into an ovary or testis is unknown, but it is known that steroid hormones play an important role. During the TSP, exogenous application of estrogen can override a temperature cue and produce females, while blocking the activity of aromatase (Cyp19a1), the enzyme that converts testosterone to estradiol, produces males from a female-biased temperature. The production of estrogen is a key step in ovarian differentiation for many vertebrates, including TSD reptiles, and temperature-based differences in aromatase expression during the TSP may be a critical step in ovarian determination. Steroidogenic factor-1 (Sf1) is a key gene in vertebrate sex determination and regulates many steroidogenic enzymes, including aromatase. We find that Sf1 and aromatase are differentially expressed during sex determination in the red-eared slider turtle, Trachemys scripta elegans. Sf1 is expressed at higher levels during testis development while aromatase expression increases during ovary determination. We also assayed Sf1 and aromatase response to sex-reversing treatments via temperature or the modulation of estrogen availability. Sf1 expression was redirected to low-level female-specific patterns with feminizing temperature shift or exogenous estradiol application and redirected to more intense male-specific patterns with male-producing temperature shift or inhibition of aromatase activity. Conversely, aromatase expression was redirected to more intense female-specific patterns with female-producing treatment and redirected toward diffuse low-level male-specific patterns with masculinizing sex reversal. Our data do not lend support to a role for Sf1 in the regulation of aromatase expression during slider turtle sex

  11. Combining Src inhibitors and aromatase inhibitors: a novel strategy for overcoming endocrine resistance and bone loss.

    PubMed

    Hiscox, Stephen; Barrett-Lee, Peter; Borley, Annabel C; Nicholson, Robert I

    2010-08-01

    Aromatase inhibitors have largely replaced tamoxifen as the first-line treatment for postmenopausal women with metastatic, hormone receptor-positive (HR+) breast cancer. However, many patients develop clinical resistance with prolonged treatment, and oestrogen deprivation following aromatase inhibition can result in loss of bone mineral density. Furthermore, most patients with metastatic breast cancer develop bone metastases, and the resulting adverse skeletal-related events are a significant cause of patient morbidity. Src, a non-receptor tyrosine kinase, is a component of signalling pathways that regulate breast cancer cell proliferation, invasion and metastasis as well as osteoclast-mediated bone turnover. Preclinical evidence also suggests a role for Src in acquired endocrine resistance. As such, Src inhibition represents a logical strategy for the treatment of metastatic breast cancer. In vitro, combination therapy with Src inhibitors and endocrine agents, including aromatase inhibitors, has been shown to inhibit the proliferation and metastasis of both endocrine-responsive and endocrine-resistant breast cancer cell lines more effectively than either of the therapy alone. Src inhibition has also been shown to suppress osteoclast formation and activity. Combination therapy with aromatase inhibitors and Src inhibitors therefore represents a novel approach through which the development of both acquired resistance and bone pathology could be delayed. Data from clinical trials utilising such combinations will reveal if this strategy has the potential to improve patient outcomes. Copyright 2010 Elsevier Ltd. All rights reserved.

  12. Effect of pregnant mare's serum gonadotrophin on the activities of delta 4-5 alpha-reductase, aromatase, and other enzymes in the ovaries of immature rats.

    PubMed

    Suzuki, K; Kawakura, K; Tamaoki, B I

    1978-05-01

    After incubation of progesterone, 17 alpha-hydroxyprogesterone, androstenedione, and testostrone with an ovarian preparation (supernatant fluid at 10,000 x g) of immature rats (21-23 days of age) in the presence of NADPH, 3 alpha- and 3 beta-hydroxy-5 alpha-reduced steroids were obtained as the major metabolites. Among the enzyme activities relevant to the metabolism, delta 4-5 alpha-reductase and 3 beta-hydroxysteroid dehydrogenase were intracellularly localized to the microsomal fraction (10,000--105,000 x g), and 3 alpha-hydroxysteroid dehydrogenase was detected exclusively in the cytosol fraction (supernatant fluid at 105,000 x g). Within 2 days after a single injection of pregnant mare's serum gonadotrophin (10 IU/rat) to 21-day-old female rats, the following occurred: 1) an enhancement of 17 alpha-hydroxylase and C-17-C-20 lyase activities; 2) a suppression of delta 4-5 alpha-reductase activity; and 3) an increase in aromatizing activity. From the above-mentioned results, it was concluded that the increased secretion of estrogen from ovaries of immature rats stimulated by pregnant mare's serum gonadotrophin administration was caused by a modification of the ovarian enzyme activities relevant to estrogen production.

  13. Des-acyl ghrelin inhibits the capacity of macrophages to stimulate the expression of aromatase in breast adipose stromal cells.

    PubMed

    Au, CheukMan C; Docanto, Maria M; Zahid, Heba; Raffaelli, Francesca-Maria; Ferrero, Richard L; Furness, John B; Brown, Kristy A

    2017-06-01

    Des-acyl ghrelin is the unacylated form of the well-characterized appetite-stimulating hormone ghrelin. It affects a number of physiological processes, including increasing adipose lipid accumulation and inhibiting adipose tissue inflammation. Breast adipose tissue inflammation in obesity is associated with an increase in the expression of the estrogen biosynthetic enzyme, aromatase, and is hypothesized to create a hormonal milieu conducive to tumor growth. We previously reported that des-acyl ghrelin inhibits the expression and activity of aromatase in isolated human adipose stromal cells (ASCs), the main site of aromatase expression in the adipose tissue. The current study aimed to examine the effect of des-acyl ghrelin on the capacity of mouse macrophages (RAW264.7 cells) and human adipose tissue macrophages (ATMs) to stimulate aromatase expression in primary human breast ASCs. RAW264.7 cells were treated with 0, 10 and 100pM des-acyl ghrelin following activation with phorbol 12-myristate 13-acetate, and cells and conditioned media were collected after 6 and 24h. The effect of des-acyl ghrelin on macrophage polarization was examined by assessing mRNA expression of pro-inflammatory M1-specific marker Cd11c and anti-inflammatory M2-specific marker Cd206, as well as expression of Tnf and Ptgs2, known mediators of the macrophage-dependent stimulation of aromatase. TNF protein in conditioned media was assessed by ELISA. The effect of RAW264.7 and ATM-conditioned media on aromatase expression in ASCs was assessed after 6h. Results demonstrate des-acyl ghrelin significantly increases the expression of Cd206 and suppresses the expression of Cd11c, Tnf and Ptgs2 in activated RAW264.7 cells. Treatment of RAW264.7 and ATMs with des-acyl ghrelin also significantly reduces the capacity of these cells to stimulate aromatase transcript expression in human breast ASCs. Overall, these findings suggest that in addition to direct effects on aromatase in ASCs, des-acyl ghrelin also

  14. Estrogen biosynthesis in THP1 cells is regulated by promoter switching of the aromatase (CYP19) gene.

    PubMed

    Shozu, M; Zhao, Y; Simpson, E R

    1997-12-01

    The expression of aromatase, the enzyme responsible for estrogen biosynthesis, has been studied in THP-1 cells of human mononuclear leukemic origin, which exhibit high rates of aromatase activity. These cells have the capacity to differentiate in the presence of vitamin D into cells with osteoclast-like properties. Differentiated cells displayed higher rates of aromatase than undifferentiated cells, and, in both cases, activity was stimulated 10- to 20-fold by dexamethasone. Phorbol esters also increased aromatase activity, but the effect was the same in differentiated as in undifferentiated cells. In a similar fashion to adipose stromal cells, serum potentiated the response to dexamethasone but had no effect on phorbol ester-stimulated activity. By contrast to its action in adipose stromal cells, (Bu)2cAMP markedly inhibited aromatase activity of THP-1 cells, as did factors whose actions are mediated by cAMP, such as PTH and PTH-related peptide. This was true of control cells, as well as of dexamethasone- and phorbol ester-stimulated cells. Previously we have shown that type 1 cytokines as well as tumor necrosis factor-alpha stimulate aromatase activity of adipose stromal cells in the presence of dexamethasone. By contrast, interleukin-6, interleukin-11, and leukemia-inhibitory factor had no effect on aromatase activity of THP-1 cells, whereas tumor necrosis factor-alpha, oncostatin M, and platelet-derived growth factor were slightly inhibitory of aromatase activity. Exon-specific Southern analysis of rapid amplification of cDNA ends-amplified transcripts was employed to examine the distribution of the various 5'-termini of aromatase transcripts. In the control group, most of the clones contained transcripts specific for the proximal promoter II, whereas in dexamethasone-treated cells, most transcripts contained exon I.4. In the phorbol ester-treated cells, a broader spectrum of transcripts was present, with equal proportions of I.4, II, and I.3-containing clones

  15. Unique Distribution of Aromatase in the Human Brain: In Vivo Studies With PET and [N-Methyl-11C]Vorozole

    SciTech Connect

    Biegon, A.; Biegon, A.; Kim, S.W.

    Aromatase catalyzes the last step in estrogen biosynthesis. Brain aromatase is involved in diverse neurophysiological and behavioral functions including sexual behavior, aggression, cognition, and neuroprotection. Using positron emission tomography (PET) with the radiolabeled aromatase inhibitor [N-methyl-{sup 11}C]vorozole, we characterized the tracer distribution and kinetics in the living human brain. Six young, healthy subjects, three men and three women, were administered the radiotracer alone on two separate occasions. Women were scanned in distinct phases of the menstrual cycle. Specificity was confirmed by pretreatment with a pharmacological (2.5 mg) dose of the aromatase inhibitor letrozole. PET data were acquired over a 90-minmore » period and regions of interest placed over selected brain regions. Brain and plasma time activity curves, corrected for metabolites, were used to derive kinetic parameters. Distribution volume (V{sub T}) values in both men and women followed the following rank order: thalamus > amygdala = preoptic area > medulla (inferior olive) > accumbens, pons, occipital and temporal cortex, putamen, cerebellum, and white matter. Pretreatment with letrozole reduced VT in all regions, though the size of the reduction was region-dependent, ranging from {approx}70% blocking in thalamus andpreoptic area to {approx}10% in cerebellum. The high levels of aromatase in thalamus and medulla (inferior olive) appear to be unique to humans. These studies set the stage for the noninvasive assessment of aromatase involvement in various physiological and pathological processes affecting the human brain.« less

  16. Aromatase imaging with [N-methyl-C-11]vorozole PET in healthy men and women

    DOE PAGES

    Biegon, Anat; Fowler, Joanna S.; Alexoff, David L.; ...

    2015-02-19

    Aromatase, the last and obligatory enzyme catalyzing estrogen biosynthesis from androgenic precursors, can be labeled in vivo with ¹¹C-vorozole. Aromatase inhibitors are widely used in breast cancer and other endocrine conditions. The present study aims to provide baseline information defining aromatase distribution in healthy men and women, against which its perturbation in pathological situations can be studied. Methods: ¹¹C-vorozole (111-296 MBq/subject) was injected I.V in 13 men and 20 women (age range 23 to 67). PET data were acquired over a 90 minute period. Each subject had 4 scans, 2/day separated by 2-6 weeks, including brain and torso or pelvismore » scans. Young women were scanned at 2 discrete phases of the menstrual cycle (midcycle and late luteal). Men and postmenopausal women were also scanned following pretreatment with a clinical dose of the aromatase inhibitor letrozole (“blocking” studies). Time activity curves were obtained and standard uptake values (SUV) calculated for major organs including brain, heart, lungs, liver, kidneys, spleen, muscle, bone and male and female reproductive organs (penis, testes, uterus, ovaries). Organ and whole body radiation exposures were calculated using Olinda software. Results: Liver uptake was higher than all other organs, but was not blocked by pretreatment with letrozole. Mean SUVs in men were higher than in women, and brain uptake was blocked by letrozole. Male brain SUVs were also higher than all other organs (ranging from 0.48±0.05 in lungs to 1.5±0.13 in kidneys). Mean ovarian SUVs (3.08±0.7) were comparable to brain levels and higher than all other organs. Furthermore, ovarian SUVs In young women around the time of ovulation (midcycle) were significantly higher than those measured in the late luteal phase, while aging and cigarette smoking reduced ¹¹C-vorozole uptake. Conclusions: PET with ¹¹C-vorozole is useful for assessing physiological changes in estrogen synthesis capacity in the

  17. Aromatase imaging with [N-methyl-C-11]vorozole PET in healthy men and women

    SciTech Connect

    Biegon, Anat; Fowler, Joanna S.; Alexoff, David L.

    Aromatase, the last and obligatory enzyme catalyzing estrogen biosynthesis from androgenic precursors, can be labeled in vivo with ¹¹C-vorozole. Aromatase inhibitors are widely used in breast cancer and other endocrine conditions. The present study aims to provide baseline information defining aromatase distribution in healthy men and women, against which its perturbation in pathological situations can be studied. Methods: ¹¹C-vorozole (111-296 MBq/subject) was injected I.V in 13 men and 20 women (age range 23 to 67). PET data were acquired over a 90 minute period. Each subject had 4 scans, 2/day separated by 2-6 weeks, including brain and torso or pelvismore » scans. Young women were scanned at 2 discrete phases of the menstrual cycle (midcycle and late luteal). Men and postmenopausal women were also scanned following pretreatment with a clinical dose of the aromatase inhibitor letrozole (“blocking” studies). Time activity curves were obtained and standard uptake values (SUV) calculated for major organs including brain, heart, lungs, liver, kidneys, spleen, muscle, bone and male and female reproductive organs (penis, testes, uterus, ovaries). Organ and whole body radiation exposures were calculated using Olinda software. Results: Liver uptake was higher than all other organs, but was not blocked by pretreatment with letrozole. Mean SUVs in men were higher than in women, and brain uptake was blocked by letrozole. Male brain SUVs were also higher than all other organs (ranging from 0.48±0.05 in lungs to 1.5±0.13 in kidneys). Mean ovarian SUVs (3.08±0.7) were comparable to brain levels and higher than all other organs. Furthermore, ovarian SUVs In young women around the time of ovulation (midcycle) were significantly higher than those measured in the late luteal phase, while aging and cigarette smoking reduced ¹¹C-vorozole uptake. Conclusions: PET with ¹¹C-vorozole is useful for assessing physiological changes in estrogen synthesis capacity in the

  18. Interactions between aromatase (estrogen synthase) and dopamine in the control of male sexual behavior in quail.

    PubMed

    Balthazart, Jacques; Baillien, Michelle; Ball, Gregory F

    2002-05-01

    In male quail, like in other vertebrates including rodents, testosterone acting especially through its estrogenic metabolites is necessary for the activation of male sexual behavior. Also, the administration of dopamine agonists and antagonists profoundly influences male sexual behavior. How the steroid-sensitive neural network and dopamine interact physiologically, remains largely unknown. It is often implicitly assumed that testosterone or its metabolite estradiol, stimulates male sexual behavior via the modification of dopaminergic transmission. We have now identified in quail two possible ways in which dopamine could potentially affect sexual behavior by modulating the aromatization of testosterone into an estrogen. One is a long-acting mechanism that presumably involves the modification of dopaminergic transmission followed by the alteration of the genomic expression of aromatase. The other is a more rapid mechanism that does not appear to be dopamine receptor-mediated and may involve a direct interaction of dopamine with aromatase (possibly via substrate competition). We review here the experimental data supporting the existence of these controls of aromatase activity by dopamine and discuss the possible contribution of these controls to the activation of male sexual behavior.

  19. Two natural products, trans-phytol and (22E)-ergosta-6,9,22-triene-3β,5α,8α-triol, inhibit the biosynthesis of estrogen in human ovarian granulosa cells by aromatase (CYP19)

    SciTech Connect

    Guo, Jiajia; Yuan, Yun; School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang

    2014-08-15

    Aromatase is the only enzyme in vertebrates to catalyze the biosynthesis of estrogens. Although inhibitors of aromatase have been developed for the treatment of estrogen-dependent breast cancer, the whole-body inhibition of aromatase causes severe adverse effects. Thus, tissue-selective aromatase inhibitors are important for the treatment of estrogen-dependent cancers. In this study, 63 natural products with diverse structures were examined for their effects on estrogen biosynthesis in human ovarian granulosa-like KGN cells. Two compounds—trans-phytol (SA-20) and (22E)-ergosta-6,9,22-triene-3β,5α,8α-triol (SA-48)—were found to potently inhibit estrogen biosynthesis (IC{sub 50}: 1 μM and 0.5 μM, respectively). Both compounds decreased aromatase mRNA and protein expression levelsmore » in KGN cells, but had no effect on the aromatase catalytic activity in aromatase-overexpressing HEK293A cells and recombinant expressed aromatase. The two compounds decreased the expression of aromatase promoter I.3/II. Neither compound affected intracellular cyclic AMP (cAMP) levels, but they inhibited the phosphorylation or protein expression of cAMP response element-binding protein (CREB). The effects of these two compounds on extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinases (MAPKs), and AKT/phosphoinositide 3-kinase (PI3K) pathway were examined. Inhibition of p38 MAPK could be the mechanism underpinning the actions of these compounds. Our results suggests that natural products structurally similar to SA-20 and SA-48 may be a new source of tissue-selective aromatase modulators, and that p38 MAPK is important in the basal control of aromatase in ovarian granulosa cells. SA-20 and SA-48 warrant further investigation as new pharmaceutical tools for the prevention and treatment of estrogen-dependent cancers. - Highlights: • Two natural products inhibited estrogen biosynthesis in human ovarian granulosa cells.

  20. Review: aromatase inhibitors for ovulation induction.

    PubMed

    Casper, Robert F; Mitwally, Mohamed F M

    2006-03-01

    For the last 40 yr, the first line of treatment for anovulation in infertile women has been clomiphene citrate (CC). CC is a safe, effective oral agent but is known to have relatively common antiestrogenic endometrial and cervical mucous side effects that could prevent pregnancy in the face of successful ovulation. In addition, there is a significant risk of multiple pregnancy with CC, compared with natural cycles. Because of these problems, we proposed the concept of aromatase inhibition as a new method of ovulation induction that could avoid many of the adverse effects of CC. The objective of this review was to describe the different physiological mechanisms of action for CC and aromatase inhibitors (AIs) and compare studies of efficacy for both agents for ovulation induction. We conducted a systematic review of all the published studies, both controlled and noncontrolled, comparing CC and AI treatment, either alone or in combination with gonadotropins, for ovulation induction or augmentation, identified through the Entrez-PubMed search engine. Because of the recent acceptance of the concept of using AIs for ovulation induction, few controlled studies were identified, and the rest of the studies were pilot or preliminary comparisons. Based on these studies, it appears that AIs are as effective as CC in inducing ovulation, are devoid of any antiestrogenic side effects, result in lower serum estrogen concentrations, and are associated with good pregnancy rates with a lower incidence of multiple pregnancy than CC. When combined with gonadotropins for assisted reproductive technologies, AIs reduce the dose of FSH required for optimal follicle recruitment and improve the response to FSH in poor responders. Preliminary evidence suggests that AIs may replace CC in the future because of similar efficacy with a reduced side effect profile. Although worldwide experience with AIs for ovulation induction is increasing, at present, definitive studies in the form of randomized

  1. Estrogen Receptor-Related Receptor α Mediates Up-Regulation of Aromatase Expression by Prostaglandin E2 in Prostate Stromal Cells

    PubMed Central

    Miao, Lin; Shi, Jiandang; Wang, Chun-Yu; Zhu, Yan; Du, Xiaoling; Jiao, Hongli; Mo, Zengnan; Klocker, Helmut; Lee, Chung; Zhang, Ju

    2010-01-01

    Estrogen receptor-related receptor α (ERRα) is an orphan member of the nuclear receptor superfamily of transcription factors. ERRα is highly expressed in the prostate, especially in prostate stromal cells. However, little is known about the regulation and function of ERRα, which may contribute to the progression of prostatic diseases. We previously found that prostaglandin E2 (PGE2) up-regulated the expression of aromatase in prostate stromal cells. Here we show that PGE2 also up-regulates the expression of ERRα, which, as a transcription factor, further mediates the regulatory effects of PGE2 on the expression of aromatase. ERRα expression was up-regulated by PGE2 in prostate stromal cell line WPMY-1, which was mediated mainly through the protein kinase A signaling pathway by PGE2 receptor EP2. Suppression of ERRα activity by chlordane (an antagonist of ERRα) or small interfering RNA knockdown of ERRα blocked the increase of expression and promoter activity of aromatase induced by PGE2. Overexpression of ERRα significantly increased aromatase expression and promoter activity, which were further augmented by PGE2. Chromatin immunoprecipitation assay demonstrated that ERRα directly bound to the aromatase promoter in vivo, and PGE2 enhanced the recruitment of ERRα and promoted transcriptional regulatory effects on aromatase expression in WPMY-1. 17β-Estradiol concentration in WPMY-1 medium was up-regulated by ERRα expression, and that was further increased by PGE2. Our results provided evidence that ERRα contributed to local estrogen production by up-regulating aromatase expression in response to PGE2 and provided further insights into the potential role of ERRα in estrogen-related prostatic diseases. PMID:20351196

  2. BRCA1/BARD1 Complex Interacts with Steroidogenic Factor 1----a Potential Mechanism for Regulation of Aromatase Expression by BRCA1

    PubMed Central

    Lu, Yunzhe; Kang, Tao; Hu, Yanfen

    2010-01-01

    Germline mutations in BRCA1 predispose women to early onset of breast and ovarian cancers. Findings from previous studies support the notion that the tissue- and gender-specific tumor suppression function of BRCA1 is associated with its role in negative regulation of aromatase expression, the rate-limiting step in estrogen biosynthesis. The molecular mechanism of BRCA1 in regulating aromatase promoter activity remains to be elucidated. In this study, we demonstrate that, in an ovarian granulosa cell line KGN, steroidogenic factor 1 (SF-1) is required for aromatase PII promoter basal activity as well as the elevated aromatase expression mediated by BRCA1 knockdown. Furthermore, BRCA1 in KGN cells exists mainly as a heterodimer with BARD1. We provide evidence that the BRCA1/BARD1 complex interacts with SF-1 both in vivo and in vitro. However, the intrinsic ubiquitin E3 ligase activity of BRCA1/BARD1 does not appear to contribute to ubiquitynation of SF-1. We propose that the interaction between SF-1 and BRCA1/BARD1 may recruit BRCA1/BARD1 complex to the aromatase PII promoter for BRCA1/BARD1-mediate transcriptional repression. PMID:21087664

  3. Assessment of differences in sensitivity to aromatase inhibitors among freshwater fish species

    EPA Science Inventory

    There is significant concern regarding potential impairment of fish reproduction associated with exposure to endocrine disrupting chemicals (EDCs). Aromatase is a steroidogenic enzyme involved in the conversion of androgens to estrogens. Inhibition of aromatase can reduce levels ...

  4. Synthesis and PET studies of [(11)C-cyano]letrozole (Femara), an aromatase inhibitor drug.

    PubMed

    Kil, Kun-Eek; Biegon, Anat; Ding, Yu-Shin; Fischer, Andre; Ferrieri, Richard A; Kim, Sung Won; Pareto, Deborah; Schueller, Michael J; Fowler, Joanna S

    2009-02-01

    Aromatase, a member of the cytochrome P450 family, converts androgens such as androstenedione and testosterone into estrone and estradiol, respectively. Letrozole (1-[bis-(4-cyanophenyl)methyl]-1H-1,2,4-triazole; Femara) is a high-affinity aromatase inhibitor (K(i)=11.5 nM) that has Food and Drug Administration approval for breast cancer treatment. Here we report the synthesis of carbon-11-labeled letrozole and its assessment as a radiotracer for brain aromatase in the baboon. Letrozole and its precursor (4-[(4-bromophenyl)-1H-1,2,4-triazol-1-ylmethyl]benzonitrile) were prepared in a two-step synthesis from 4-cyanobenzyl bromide and 4-bromobenzyl bromide, respectively. The [(11)C]cyano group was introduced via tetrakis(triphenylphosphine)palladium(0)-catalyzed coupling of [(11)C]cyanide with the bromo precursor. Positron emission tomography (PET) studies in the baboon brain were carried out to assess regional distribution and kinetics, reproducibility of repeated measures and saturability. Log D, the free fraction of letrozole in plasma and the [(11)C-cyano]letrozole fraction in arterial plasma were also measured. [(11)C-cyano]Letrozole was synthesized in 60 min with a radiochemical yield of 79-80%, with a radiochemical purity greater than 98% and a specific activity of 4.16+/-2.21 Ci/mumol at the end of bombardment (n=4). PET studies in the baboon revealed initial rapid and high uptake and initial rapid clearance, followed by slow clearance of carbon-11 from the brain, with no difference between brain regions. Brain kinetics was not affected by coinjection of unlabeled letrozole (0.1 mg/kg). The free fraction of letrozole in plasma was 48.9%, and log D was 1.84. [(11)C-cyano]Letrozole is readily synthesized via a palladium-catalyzed coupling reaction with [(11)C]cyanide. Although it is unsuitable as a PET radiotracer for brain aromatase, as revealed by the absence of regional specificity and saturability in brain regions such as amygdala, which are known to

  5. Aromatase expression in a human osteoblastic cell line increases in response to prostaglandin E(2) in a dexamethasone-dependent fashion.

    PubMed

    Watanabe, M; Noda, M; Nakajin, S

    2007-09-01

    Recent progress supports the importance of local estrogen secretion in human bone tissue to increase and maintain bone-mineral density. In a previous report, we found that forskolin (FSK) synergistically induces aromatase (CYP19: a rate-limiting enzyme for estrogen synthesis) expression in dexamethasone (Dex) dependent manner in a human osteoblastic cell line, SV-HFO [Watanabe M, Ohno S, Nakajin S. Forskolin and dexamethasone synergistically induce aromatase (CYP19) expression in the human osteoblastic cell line SV-HFO. Eur J Endocrinol 2005;152:619-24]. In this report, we investigated whether prostaglandin (PG) E(2) induces estrogen production, in other words, if PGE(2) exerts the same effect as FSK because PGE(2) is the major prostanoid in the bone and is one of the key molecules in the osteoblast. We found PGE(2) up-regulates aromatase activity synergistically, but this up-regulation depends on Dex. CYP19 gene expression was also increased synergistically by Dex and PGE(2). Promoter I.4 was activated synergistically by PGE(2) and Dex. PGE(2) receptor, EP(1), EP(2) and EP(4) were involved in the up-regulation of aromatase activity in response to PGE(2) in a Dex-dependent manner. The cAMP-PKA pathway and Ca(2+) signaling pathway were involved in the up-regulation of aromatase activity in response to PGE(2). Furthermore, glucocorticoid response element on promoter I.4 sequence was an essential minimum requirement for its activity and synergism of PGE(2) and Dex. These findings are the first report on osteoblastic cell line which uses predominantly promoter I.4 to drive aromatase expression. These findings also suggest that endogenous PGE(2) produced in bone mainly may synergistically support local estrogen production in osteoblastic cells in the presence of glucocorticoid.

  6. The sex-specific associations of the aromatase gene with Alzheimer's disease and its interaction with IL10 in the Epistasis Project.

    PubMed

    Medway, Christopher; Combarros, Onofre; Cortina-Borja, Mario; Butler, Helen T; Ibrahim-Verbaas, Carla A; de Bruijn, Renée F A G; Koudstaal, Peter J; van Duijn, Cornelia M; Ikram, M Arfan; Mateo, Ignacio; Sánchez-Juan, Pascual; Lehmann, Michael G; Heun, Reinhard; Kölsch, Heike; Deloukas, Panos; Hammond, Naomi; Coto, Eliecer; Alvarez, Victoria; Kehoe, Patrick G; Barber, Rachel; Wilcock, Gordon K; Brown, Kristelle; Belbin, Olivia; Warden, Donald R; Smith, A David; Morgan, Kevin; Lehmann, Donald J

    2014-02-01

    Epistasis between interleukin-10 (IL10) and aromatase gene polymorphisms has previously been reported to modify the risk of Alzheimer's disease (AD). However, although the main effects of aromatase variants suggest a sex-specific effect in AD, there has been insufficient power to detect sex-specific epistasis between these genes to date. Here we used the cohort of 1757 AD patients and 6294 controls in the Epistasis Project. We replicated the previously reported main effects of aromatase polymorphisms in AD risk in women, for example, adjusted odds ratio of disease for rs1065778 GG=1.22 (95% confidence interval: 1.01-1.48, P=0.03). We also confirmed a reported epistatic interaction between IL10 rs1800896 and aromatase (CYP19A1) rs1062033, again only in women: adjusted synergy factor=1.94 (1.16-3.25, 0.01). Aromatase, a rate-limiting enzyme in the synthesis of estrogens, is expressed in AD-relevant brain regions ,and is downregulated during the disease. IL-10 is an anti-inflammatory cytokine. Given that estrogens have neuroprotective and anti-inflammatory activities and regulate microglial cytokine production, epistasis is biologically plausible. Diminishing serum estrogen in postmenopausal women, coupled with suboptimal brain estrogen synthesis, may contribute to the inflammatory state, that is a pathological hallmark of AD.

  7. Possible role of the aromatase-independent steroid metabolism pathways in hormone responsive primary breast cancers.

    PubMed

    Hanamura, Toru; Niwa, Toshifumi; Gohno, Tatsuyuki; Kurosumi, Masafumi; Takei, Hiroyuki; Yamaguchi, Yuri; Ito, Ken-ichi; Hayashi, Shin-ichi

    2014-01-01

    Aromatase inhibitors (AIs) exert antiproliferative effects by reducing local estrogen production from androgens in postmenopausal women with hormone-responsive breast cancer. Previous reports have shown that androgen metabolites generated by the aromatase-independent enzymes, 5α-androstane-3β, 17β-diol (3β-diol), androst-5-ene-3β, and 17β-diol (A-diol), also activate estrogen receptor (ER) α. Estradiol (E2) can also reportedly be generated from estrone sulfate (E1S) pooled in the plasma. Estrogenic steroid-producing aromatase-independent pathways have thus been proposed as a mechanism of AI resistance. However, it is unclear whether these pathways are functional in clinical breast cancer. To investigate this issue, we assessed the transcriptional activities of ER in 45 ER-positive human breast cancers using the adenovirus estrogen-response element-green fluorescent protein assay and mRNA expression levels of the ER target gene, progesterone receptor, as indicators of ex vivo and in vivo ER activity, respectively. We also determined mRNA expression levels of 5α-reductase type 1 (SRD5A1) and 3β-hydroxysteroid dehydrogenase type 1 (3β-HSD type 1; HSD3B1), which produce 3β-diol from androgens, and of steroid sulfatase (STS) and 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD type 1; HSD17B1), which produce E2 or A-diol from E1S or dehydroepiandrosterone sulfate. SRD5A1 and HSD3B1 expression levels were positively correlated with ex vivo and in vivo ER activities. STS and HSD17B1 expression levels were positively correlated with in vivo ER activity alone. Elevated expression levels of these steroid-metabolizing enzymes in association with high in vivo ER activity were particularly notable in postmenopausal patients. Analysis of the expression levels of steroid-metabolizing enzymes revealed positive correlations between SRD5A1 and HSD3B1, and STS and HSD17B1. These findings suggest that the SRD5A1-HSD3B1 as well as the STS-HSD17B pathways, could contributes

  8. Efficacy and mechanism of action of Proellex, an antiprogestin in aromatase overexpressing and Letrozole resistant T47D breast cancer cells.

    PubMed

    Gupta, Akash; Mehta, Rajeshwari; Alimirah, Fatouma; Peng, Xinjian; Murillo, Genoveva; Wiehle, Ronald; Mehta, Rajendra G

    2013-01-01

    Aromatase inhibitors (AI) are considered as a first line therapy for ER+PR+ breast cancers. However, many patients acquire resistance to AI. In this study, we determined the response of antiprogestin CDB-4124 (Proellex) on the aromatase overexpressing and Letrozole resistant cell lines and also studies its mechanism of action in inhibition of breast cancer cell proliferation. For these studies we generated aromatase overexpressing T47D (T47Darom) and respective control (T47Dcon) breast cancer cell lines by stable transfection with plasmid containing CYP19A1 gene, or empty vector respectively. Letrozole resistant cell line (T47DaromLR) was generated by incubating T47Darom for 75 weeks in the presence of 10 μM Letrozole. Cell proliferation was determined by MTT or crystal violet assays. Gene expressions were quantified by QRT-PCR whereas proteins were identified by western blot analyses, flow cytometry and immunofluorescence staining. Aromatase activity was determined by estradiol ELISA. The effects of Proellex on the anchorage independent growth were measured by soft agar colony formation. Statistical differences between the various groups were determined by Student's 't' test or ANOVA followed by Bonferroni's post hoc test. Results showed that T47Darom and T47DaromLR cell lines had significantly higher aromatase expression (mRNA; 80-90 fold and protein) and as a result exhibited increased aromatization of testosterone to estradiol as compared to T47Dcon. Both these cell lines showed enhanced growth in the presence of Testosterone (50-60%). In T47DaromLR cells increased PR-B and EGFR expression as compared to T47Dcon cells was observed. Proellex and other known aromatase inhibitors (Letrozole, Anastrozole, and Exemestane) inhibited testosterone induced cell proliferation and anchorage independent growth of T47Darom cells. Cell growth inhibition was significantly greater when cells were treated with Proellex alone or in combination with other AIs as compared to AIs

  9. The novel antibacterial compound walrycin A induces human PXR transcriptional activity

    PubMed Central

    Berthier, Alexandre; Oger, Frédérik; Gheeraert, Céline; Boulahtouf, Abdel; Le Guével, Rémy; Balaguer, Patrick; Staels, Bart; Salbert, Gilles; Lefebvre, Philippe

    2012-01-01

    The human pregnane X receptor (PXR) is a ligand-regulated transcription factor belonging to the nuclear receptor superfamily. PXR is activated by a large, structurally diverse, set of endogenous and xenobiotic compounds, and coordinates the expression of genes central to metabolism and excretion of potentially harmful chemicals and therapeutic drugs in humans. Walrycin A is a novel antibacterial compound targeting the WalK/WalR two-component signal transduction system of Gram (+) bacteria. Here we report that, in hepatoma cells, walrycin A potently activates a gene set known to be regulated by the xenobiotic sensor PXR. Walrycin A was as efficient as the reference PXR agonist rifampicin to activate PXR in a transactivation assay at non cytoxic concentrations. Using a limited proteolysis assay, we show that walrycin A induces conformational changes at a concentration which correlates with walrycin A ability to enhance the expression of prototypic target genes, suggesting that walrycin A interacts with PXR. The activation of the canonical human PXR target gene CYP3A4 by walrycin A is dose- and PXR-dependent. Finally, in silico docking experiments suggest that the walrycin A oxidation product Russig’s blue is the actual a ligand for PXR. Taken together, these results identify walrycin A as novel human PXR activator. PMID:22314385

  10. Cell-Based High-Throughput Screening for Aromatase Inhibitors in the Tox21 10K Library

    PubMed Central

    Chen, Shiuan; Hsieh, Jui-Hua; Huang, Ruili; Sakamuru, Srilatha; Hsin, Li-Yu; Xia, Menghang; Shockley, Keith R.; Auerbach, Scott; Kanaya, Noriko; Lu, Hannah; Svoboda, Daniel; Witt, Kristine L.; Merrick, B. Alex; Teng, Christina T.; Tice, Raymond R.

    2015-01-01

    Multiple mechanisms exist for endocrine disruption; one nonreceptor-mediated mechanism is via effects on aromatase, an enzyme critical for maintaining the normal in vivo balance of androgens and estrogens. We adapted the AroER tri-screen 96-well assay to 1536-well format to identify potential aromatase inhibitors (AIs) in the U.S. Tox21 10K compound library. In this assay, screening with compound alone identifies estrogen receptor alpha (ERα) agonists, screening in the presence of testosterone (T) identifies AIs and/or ERα antagonists, and screening in the presence of 17β-estradiol (E2) identifies ERα antagonists. Screening the Tox-21 library in the presence of T resulted in finding 302 potential AIs. These compounds, along with 31 known AI actives and inactives, were rescreened using all 3 assay formats. Of the 333 compounds tested, 113 (34%; 63 actives, 50 marginal actives) were considered to be potential AIs independent of cytotoxicity and ER antagonism activity. Structure-activity analysis suggested the presence of both conventional (eg, 1, 2, 4, - triazole class) and novel AI structures. Due to their novel structures, 14 of the 63 potential AI actives, including both drugs and fungicides, were selected for confirmation in the biochemical tritiated water-release aromatase assay. Ten compounds were active in the assay; the remaining 4 were only active in high-throughput screen assay, but with low efficacy. To further characterize these 10 novel AIs, we investigated their binding characteristics. The AroER tri-screen, in high-throughput format, accurately and efficiently identified chemicals in a large and diverse chemical library that selectively interact with aromatase. PMID:26141389

  11. Cell-Based High-Throughput Screening for Aromatase Inhibitors in the Tox21 10K Library.

    PubMed

    Chen, Shiuan; Hsieh, Jui-Hua; Huang, Ruili; Sakamuru, Srilatha; Hsin, Li-Yu; Xia, Menghang; Shockley, Keith R; Auerbach, Scott; Kanaya, Noriko; Lu, Hannah; Svoboda, Daniel; Witt, Kristine L; Merrick, B Alex; Teng, Christina T; Tice, Raymond R

    2015-10-01

    Multiple mechanisms exist for endocrine disruption; one nonreceptor-mediated mechanism is via effects on aromatase, an enzyme critical for maintaining the normal in vivo balance of androgens and estrogens. We adapted the AroER tri-screen 96-well assay to 1536-well format to identify potential aromatase inhibitors (AIs) in the U.S. Tox21 10K compound library. In this assay, screening with compound alone identifies estrogen receptor alpha (ERα) agonists, screening in the presence of testosterone (T) identifies AIs and/or ERα antagonists, and screening in the presence of 17β-estradiol (E2) identifies ERα antagonists. Screening the Tox-21 library in the presence of T resulted in finding 302 potential AIs. These compounds, along with 31 known AI actives and inactives, were rescreened using all 3 assay formats. Of the 333 compounds tested, 113 (34%; 63 actives, 50 marginal actives) were considered to be potential AIs independent of cytotoxicity and ER antagonism activity. Structure-activity analysis suggested the presence of both conventional (eg, 1, 2, 4, - triazole class) and novel AI structures. Due to their novel structures, 14 of the 63 potential AI actives, including both drugs and fungicides, were selected for confirmation in the biochemical tritiated water-release aromatase assay. Ten compounds were active in the assay; the remaining 4 were only active in high-throughput screen assay, but with low efficacy. To further characterize these 10 novel AIs, we investigated their binding characteristics. The AroER tri-screen, in high-throughput format, accurately and efficiently identified chemicals in a large and diverse chemical library that selectively interact with aromatase. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. A pilot randomized trial to prevent sexual dysfunction in postmenopausal breast cancer survivors starting adjuvant aromatase inhibitor therapy.

    PubMed

    Advani, Pragati; Brewster, Abenaa M; Baum, George P; Schover, Leslie R

    2017-08-01

    A randomized pilot trial evaluated the hypothesis that early intervention lessens sexual dysfunction in the first year on aromatase inhibitors. A secondary aim was comparing the efficacy of two vaginal moisturizers. Fifty-seven postmenopausal women with early stage breast cancer starting aromatase inhibitors were randomized to three treatment groups. All received a handout on managing sexual and other side effects. The Usual Care group received no additional therapy. The Active Treatment groups received a 6-month supply of a vaginal moisturizer (hyaluronic acid-based in Active Group-H and prebiotic in Active Group-P) and a vaginal lubricant and dilator, plus access to an educational website and phone coaching. Questionnaires completed at baseline, 6, and 12 months included the Female Sexual Function Index (FSFI), Menopausal Sexual Interest Questionnaire (MSIQ), Female Sexual Distress Scale-Revised (FSDS-R), and a menopausal symptom scale. Forty-nine women (86%) provided follow-up data. Mean age was 59 and 77% were non-Hispanic Caucasian. Sexual function was impaired at baseline, but remained stable over 12 months for all groups. The combined active treatment group had less dyspareunia (P = 0.07) and sexual distress (P = 0.02) at 6 months than the Usual Care group. At 6 months, the Active-H group improved significantly more than the Active-P group on FSFI total score (P = 0.04). Sexual counseling helped women maintain stable sexual function on aromatase inhibitors. Active intervention resulted in better outcomes at 6 months. This promising pilot trial suggests a need for more research on preventive counseling to maintain sexual function during aromatase inhibitor treatment.

  13. Natural Product Vibsanin A Induces Differentiation of Myeloid Leukemia Cells through PKC Activation.

    PubMed

    Yu, Zu-Yin; Xiao, He; Wang, Li-Mei; Shen, Xing; Jing, Yu; Wang, Lin; Sun, Wen-Feng; Zhang, Yan-Feng; Cui, Yu; Shan, Ya-Jun; Zhou, Wen-Bing; Xing, Shuang; Xiong, Guo-Lin; Liu, Xiao-Lan; Dong, Bo; Feng, Jian-Nan; Wang, Li-Sheng; Luo, Qing-Liang; Zhao, Qin-Shi; Cong, Yu-Wen

    2016-05-01

    All-trans retinoic acid (ATRA)-based cell differentiation therapy has been successful in treating acute promyelocytic leukemia, a unique subtype of acute myeloid leukemia (AML). However, other subtypes of AML display resistance to ATRA-based treatment. In this study, we screened natural, plant-derived vibsane-type diterpenoids for their ability to induce differentiation of myeloid leukemia cells, discovering that vibsanin A potently induced differentiation of AML cell lines and primary blasts. The differentiation-inducing activity of vibsanin A was mediated through direct interaction with and activation of protein kinase C (PKC). Consistent with these findings, pharmacological blockade of PKC activity suppressed vibsanin A-induced differentiation. Mechanistically, vibsanin A-mediated activation of PKC led to induction of the ERK pathway and decreased c-Myc expression. In mouse xenograft models of AML, vibsanin A administration prolonged host survival and inhibited PKC-mediated inflammatory responses correlated with promotion of skin tumors in mice. Collectively, our results offer a preclinical proof of concept for vibsanin A as a myeloid differentiation-inducing compound, with potential application as an antileukemic agent. Cancer Res; 76(9); 2698-709. ©2016 AACR. ©2016 American Association for Cancer Research.

  14. Aromatase Blockade Is Associated With Increased Mortality in Acute Illness in Male Mice.

    PubMed

    Connerney, Jeannette J; Spratt, Daniel I

    2017-09-01

    The increase in circulating estrogen levels with acute illness in humans is accompanied by increased aromatase expression in adipose tissue and increased peripheral aromatization of estrogens to androgens. Animal studies indicate that estrogen may be beneficial in acute illness. We hypothesized that blockade of aromatase in acute illness would decrease survival. Prospective sham controlled. Maine Medical Center Research Institute animal facility. Six- to 8-week-old male black 6 mice. Mice underwent cecal ligation and puncture (CLP) to induce acute illness and were administered letrozole to block aromatase or saline. Mice undergoing sham surgery with or without letrozole served as controls. Adipose and cardiovascular tissue was harvested for preliminary evaluation of aromatase expression. Survival was the main outcome measurement. Evidence for aromatase expression in tissue samples was assessed using western blot and/or immunohistochemistry. With aromatase blockade, survival in CLP mice was decreased ( P = 0.04). The presence of aromatase in adipose tissue was observed by western blot in CLP but not control mice. Similarly, the presence of aromatase was observed in cardiac tissue of CLP but not in control mice. The decreased survival during sepsis with aromatase blockade suggests that this response to acute illness may be important both physiologically and clinically. The preliminary observation of aromatase expression in adipose and cardiovascular tissue during acute illness in this mouse model indicates that this model has parallels to human physiology and may be useful for further studying the aromatase response to acute illness.

  15. Cardiovascular Disease After Aromatase Inhibitor Use.

    PubMed

    Haque, Reina; Shi, Jiaxiao; Schottinger, Joanne E; Chung, Joanie; Avila, Chantal; Amundsen, Britta; Xu, Xiaoqing; Barac, Ana; Chlebowski, Rowan T

    2016-12-01

    Cardiovascular disease (CVD) is an important cause of death in older patients with breast cancer. However, limited information exists on the long-term effect of aromatase inhibitor (AI) use on CVD risk in breast cancer survivors. To this point, no other population-based studies have been able to adjust for CVD risk factors or cardiovascular medications. To determine the long-term influence of adjuvant endocrine therapies on CVD in a cohort of postmenopausal breast cancer survivors in analyses that accounted for major CVD risk factors, medication use, chemotherapy, and radiotherapy. A retrospective cohort of postmenopausal women with breast cancer diagnosed from January 1, 1991, to December 31, 2010, and followed up through December 31, 2011 (maximum, 21 years [72 886 person-years]), was evaluated using records from a managed care organization with nearly 20 community hospitals in California. A total of 13 273 postmenopausal women with hormone receptor-positive breast cancer without prior CVD were included. Cardiovascular disease incidence was compared across endocrine therapy categories. Information on demographics, comorbidity, medication, use, and CVD risk was captured from electronic health records. Multivariate Cox proportional hazards models using time-dependent endocrine drug use variables and propensity scores were conducted. Data analysis was conducted from September 15, 2014, to February 1, 2016. Women were grouped by endocrine therapy status (tamoxifen citrate only, AI only, both, or neither). Person-year rates of CVD for each therapy group. During 72 886 person-years in 13 273 women (mean [SD] age, 66.8 [8.1] years) with follow-up through 2011, we observed 3711 CVD events. In multivariable analyses (reported as hazard ratio [95% CI]), AI-only users had a similar risk of cardiac ischemia (myocardial infarction and angina) (adjusted, 0.97 [0.78-1.22]) and stroke (adjusted, 0.97 [0.70-1.33]) as tamoxifen-only users (reference). However, we found an

  16. Caught in a Network: Recovery from Aromatase Inhibition

    EPA Science Inventory

    Fadrozole is an inhibitor of aromatase, an enzyme critical to estrogen synthesis. We exposed female fathead minnows (Pimephales promelas, FHM) to 0 or 30 ug/L fadrozole for 8 days, and fish were then held in clean water for 8 extra days. We analyzed ex vivo steroid production, pl...

  17. Vaginal Gene Expression During Treatment With Aromatase Inhibitors.

    PubMed

    Kallak, Theodora Kunovac; Baumgart, Juliane; Nilsson, Kerstin; Åkerud, Helena; Poromaa, Inger Sundström; Stavreus-Evers, Anneli

    2015-12-01

    Aromatase inhibitor (AI) treatment suppresses estrogen biosynthesis and causes genitourinary symptoms of menopause such as vaginal symptoms, ultimately affecting the quality of life for many postmenopausal women with breast cancer. Thus, the aim of this study was to examine vaginal gene expression in women during treatment with AIs compared with estrogen-treated women. The secondary aim was to study the presence and localization of vaginal aromatase. Vaginal biopsies were collected from postmenopausal women treated with AIs and from age-matched control women treated with vaginal estrogen therapy. Differential gene expression was studied with the Affymetrix Gene Chip Gene 1.0 ST Array (Affymetrix Inc, Santa Clara, CA) system, Ingenuity pathway analysis, quantitative real-time polymerase chain reaction, and immunohistochemistry. The expression of 279 genes differed between the 2 groups; AI-treated women had low expression of genes involved in cell differentiation, proliferation, and cell adhesion. Some differentially expressed genes were found to interact indirectly with the estrogen receptor alpha. In addition, aromatase protein staining was evident in the basal and the intermediate vaginal epithelium layers, and also in stromal cells with a slightly stronger staining intensity found in AI-treated women. In this study, we demonstrated that genes involved in cell differentiation, proliferation, and cell adhesion are differentially expressed in AI-treated women. The expression of vaginal aromatase suggests that this could be the result of local and systemic inhibition of aromatase. Our results emphasize the role of estrogen for vaginal cell differentiation and proliferation and future drug candidates should be aimed at improving cell differentiation and proliferation. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Methadone: A Substrate and Mechanism-Based Inhibitor of CYP19 (Aromatase)

    PubMed Central

    Bies, Robert; Kamden, Landry K.; Desta, Zeruesenay; Flockhart, David A.

    2010-01-01

    The peripheral conversion of testosterone to estradiol by aromatase is the primary source of endogenous estrogen in postmenopausal women. Studies indicating that placental aromatase is able to metabolize methadone to its primary metabolite, 2-ethylidene-1, 5-dimethyl-3, 3-diphenylpyrrolidin (EDDP), led us to test the hypothesis that methadone is able to act as an inhibitor of aromatase. Using recombinant human CYP19, we examined the ability of methadone to bring about either reversible or mechanism-based inhibition of the conversion of testosterone to estradiol. To test for reversible inhibition, racemic methadone or its metabolite EDDP or 2-ethyl-5-methyl-3, 3-diphenylpyrroline (EMDP) was incubated for 30 min with testosterone at the Km (4 μM). To test for mechanism-based inhibition, microsomal preincubations were performed for up to 30 min using racemic methadone (1–1000 μM), R- or S-methadone (0.5–500 μM), or EDDP or EMDP (10 and 100 μM) followed by incubation with testosterone at a Vmax concentration (50 μM). Racemic methadone, EDDP, and EMDP did not act as competitive inhibitors of CYP19. Preincubation of methadone, EDDP, or EMDP with CYP19 resulted in time- and concentration-dependent inhibition, indicating a mechanism-based reaction that destroys CYP19 activity. The KI and kinact values for racemic methadone were calculated to be 40.6 ± 2.8 μM and 0.061 ± 0.001 min−1, respectively. No stereoselectivity was observed. Methadone is metabolized by CYP19 and may act as a potent inhibitor of CYP19 in vivo. These findings may contribute to variability in methadone clearance, to drug-drug interactions, and to side effects observed in individual patients. PMID:20410453

  19. Leptin stimulates aromatase in the growth plate: limiting catch-up growth efficiency.

    PubMed

    Masarwi, Majdi; Shamir, Raanan; Phillip, Moshe; Gat-Yablonski, Galia

    2018-06-01

    Catch-up growth (CUG) in childhood is defined as periods of growth acceleration, after the resolution of growth attenuation causes, bringing the children back to their original growth trajectory. Sometimes, however, CUG is incomplete, leading to permanent growth deficit and short stature. The aim of this study was to investigate the mechanisms that limit nutritional-CUG. Specifically, we focused on the crosstalk between leptin, increased by re-feeding, and sex hormones, which increase with age. In vivo studies were performed in young male Sprague Dawley rats fed ad libitum or subjected to 10/36 days of 40% food restriction followed by 90-120 days of re-feeding. In vitro studies were performed on ATDC5 cells. Analyses of mRNA and protein levels were done using qPCR and Western blot, respectively. CUG was complete in body weight and humerus length in animals that were food-restricted for 10 days but not for those food-restricted for 36 days. In vitro studies showed that leptin significantly increased aromatase gene expression and protein level as well as the expression of estrogen and leptin receptors in a dose- and time-dependent manner. The effect of leptin on aromatase was direct and was mediated through the MAPK/Erk, STAT3 and PI3K pathways. The crosstalk between leptin and aromatase in the growth plate suggests that re-feeding during puberty may lead to increased estrogen level and activity, and consequently, irreversible premature epiphyseal growth plate closure. These results may have important implications for the development of novel treatment strategies for short stature in children. © 2018 Society for Endocrinology.

  20. Extraction, isolation, and aromatase inhibitory evaluation of low-polar ginsenosides from Panax ginseng leaves.

    PubMed

    Zhang, Yuchi; Zhang, Jianxu; Liu, Chunming; Yu, Min; Li, Sainan

    2017-02-03

    A hyphenated accelerated solvent extraction (ASE) technique was elaborately coupled with centrifugal partition chromatography (CPC), ultra-high-performance liquid chromatography (UHPLC), and photo-diode array detector (PDA). This approach was applied to obtain low-polar ginsenoside fractions from the leaves of Panax ginseng. The CPC fractions were isolated and analyzed using the hyphenated technique, and followed by testing and evaluation of their aromatase inhibitory effects. Subsequently, the aromatase inhibition rates of the compositions in the CPC fractions were calculated using a multivariable linear regression model. A biphasic ethyl acetate/n-butanol/ethanol/water solvent system with respective volume ratios of 10:2:2:8 was used for the ASE and CPC separation of 200g of leaves of P. ginseng raw material. The (lower) aqueous phase of the abovementioned solvent system was used as the extraction solvent. The ginsenosides were subjected to ASE, and the extraction solution was pumped into the sample loop and then directly into the CPC column. The CPC fractions were collected and monitored by an online UHPLC/PDA system at 5-min intervals. The aromatase inhibitory activities of CPC fractions were analyzed by a fluorescence method, with mathematical calculations indicating that the inhibition rates of ginsenosides Rk 1 , Rg 5 , Rs 5 , 20R-Rg 3 , and Rs 4 exceeded 50.00%; indicating that the aforementioned chemical compounds have potential for further development. The results were validated by comparison with authentic standards, indicating that the method used in this research was accurate and advantageous for matrix analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Insight into the binding interactions of CYP450 aromatase inhibitors with their target enzyme: a combined molecular docking and molecular dynamics study.

    PubMed

    Galeazzi, Roberta; Massaccesi, Luca

    2012-03-01

    CYP450 aromatase catalyzes the terminal and rate-determining step in estrogen synthesis, the aromatization of androgens, and its inhibition is an efficient approach to treating estrogen-dependent breast cancer. Insight into the molecular basis of the interaction at the catalytic site between CYP450 aromatase inhibitors and the enzyme itself is required in order to design new and more active compounds. Hence, a combined molecular docking-molecular dynamics study was carried out to obtain the structure of the lowest energy association complexes of aromatase with some third-generation aromatase inhibitors (AIs) and with other novel synthesized letrozole-derived compounds which showed high in vitro activity. The results obtained clearly demonstrate the role of the pharmacophore groups present in the azaheterocyclic inhibitors (NSAIs)-namely the triazolic ring and highly functionalized aromatic moieties carrying H-bond donor or acceptor groups. In particular, it was pointed out that all of them can contribute to inhibition activity by interacting with residues of the catalytic cleft, but the amino acids involved are different for each compound, even if they belong to the same class. Furthermore, the azaheterocyclic group strongly coordinates with the Fe(II) of heme cysteinate in the most active NSAI complexes, while it prefers to adopt another orientation in less active ones.

  2. Altered Gene Expression in the Brain and Ovaries of Zebrafish Exposed to the Aromatase Inhibitor Fadrozole: Microarray analysis and Hypothesis Generation

    EPA Science Inventory

    As part of a research effort examining system-wide responses of the hypothalamic-pituitary-gonadal (HPG) axis in fish to endocrine active chemicals (EACs) with different modes of action, we exposed zebrafish (Danio rerio) to 25 or 100 ìg/L of the aromatase inhibitor fadrozole for...

  3. Altered Gene Expression in the Brain and Ovaries of Zebrafish Exposed to the Aromatase Inhibitor Fadrosole: Microarray Analysis for Hypothesis Generation

    EPA Science Inventory

    A part of an overall program of research aimed at examining system-wide responses of the hypothalamic-pituitary-gonadal axis in fish to endocrine active chemicals acting through a variety of modes of action, we exposed zebrafish (Danio rerio) to the aromatase inhibitor fadrozole ...

  4. Characterization of a cis-acting element involved in cell-specific expression of the zebrafish brain aromatase gene.

    PubMed

    Le Page, Yann; Menuet, Arnaud; Kah, Olivier; Pakdel, Farzad

    2008-10-01

    The cytochrome P450 Aromatase is the key enzyme catalyzing the conversion of androgens into estrogens. In zebrafish, the brain aromatase is encoded by cyp19b. Expression of cyp19b is restricted to radial glial cells bordering forebrain ventricles and is strongly stimulated by estrogens during development. At the promoter level, we have previously shown that an estrogen responsive element (ERE) is required for induction by estrogens. Here, we investigated the role of ERE flanking regions in the control of cell-specific expression. First, we show that a 20 bp length motif, named G x RE (glial x responsive element), acts in synergy with the ERE to mediate the estrogenic induction specifically in glial cells. Second, we demonstrate that, in vitro, this sequence binds factors exclusively present in glial or neuro-glial cells and is able to confer a glial specificity to an artificial estrogen-dependent gene. Taken together, these results contribute to the understanding of the molecular mechanisms allowing cyp19b regulation by estrogens and allowed to identify a promoter sequence involved in the strong estrogen inducibility of cyp19b which is specific for glial cells. The exceptional aromatase activity measured in the brain of teleost fish could rely on such mechanisms.

  5. Expression and regulation of aromatase and 17 beta-hydroxysteroid dehydrogenase type 4 in human THP 1 leukemia cells.

    PubMed

    Jakob, F; Homann, D; Adamski, J

    1995-12-01

    Estradiol is active in proliferation and differentiation of sex-related tissues like ovary and breast. Glandular steroid metabolism was for a long time believed to dominate the estrogenic milieu around any cell of the organism. Recent reports verified the expression of estrogen receptors in "non-target" tissues as well as the extraglandular expression of steroid metabolizing enzymes. Extraglandular steroid metabolism proved to be important in the brain, skin and in stromal cells of hormone responsive tumors. Aromatase converts testosterone into estradiol and androstenedione into estrone, thereby activating estrogen precursors. The group of 17 beta-hydroxysteroid dehydrogenases catalyzes the oxidation and/or reduction of the forementioned compounds, e.g. estradiol/estrone, thereby either activating or inactivating estradiol. Aromatase is expressed and regulated in the human THP 1 myeloid leukemia cell line after vitamin D/GMCSF-propagated differentiation. Aromatase expression is stimulated by dexamethasone, phorbolesters and granulocyte/macrophage stimulating factor (GMCSF). Exons I.2 and I.4 are expressed in PMA-stimulated cells only, exon I.3 in both PMA- and dexamethasone-stimulated cells. Vitamin D-differentiated THP 1 cells produce a net excess of estradiol in culture supernatants, if testosterone is given as aromatase substrate. In contrast, the 17 beta-hydroxysteroid dehydrogenase type 4 (17 beta-HSD 4) is abundantly expressed in unstimulated THP 1 cells and is further stimulated by glucocorticoids (2-fold). The expression is unchanged after vitamin D/GMCSF-propagated differentiation. 17 beta-HSD 4 expression is not altered by phorbolester treatment in undifferentiated cells but is abolished after vitamin D-propagated differentiation along with downregulation of beta-actin. Protein kinase C activation therefore appears to dissociate the expression of aromatase and 17 beta-HSD 4 in this differentiation stage along the monocyte/phagocyte pathway of THP 1

  6. Thymoquinone Defeats Diabetes-Induced Testicular Damage in Rats Targeting Antioxidant, Inflammatory and Aromatase Expression

    PubMed Central

    Atta, Mustafa S.; Almadaly, Essam A.; El-Far, Ali H.; Saleh, Rasha M.; Assar, Doaa H.; Al Jaouni, Soad K.; Mousa, Shaker A.

    2017-01-01

    Antioxidants have valuable effects on the process of spermatogenesis, particularly with diabetes mellitus (DM). Therefore, the present study investigated the impact and the intracellular mechanisms by which thymoquinone (TQ) works against diabetes-induced testicular deteriorations in rats. Wistar male rats (n = 60) were randomly allocated into four groups; Control, Diabetic (streptozotocin (STZ)-treated rats where diabetes was induced by intraperitoneal injection of STZ, 65 mg/kg), Diabetic + TQ (diabetic rats treated with TQ (50 mg/kg) orally once daily), and TQ (non-diabetic rats treated with TQ) for 12 weeks. Results revealed that TQ significantly improved the sperm parameters with a reduction in nitric oxide (NO) and malondialdehyde (MDA) levels in testicular tissue. Also, it increased testicular reduced glutathione (GSH) levels and superoxide dismutase (SOD) activity. Interestingly, TQ induced downregulation of testicular inducible nitric oxide synthase (iNOS) and nuclear factor kappa-B (NF-κB) and significantly upregulated the aromatase protein expression levels in testicles in comparison with the diabetic rats. In conclusion, TQ treatment exerted a protective effect against reproductive dysfunction induced by diabetes not only through its powerful antioxidant and hypoglycemic effects but also through its downregulation of testicular iNOS and NF-κB along with upregulation of aromatase expression levels in diabetic rats. PMID:28448463

  7. The planetary biology of cytochrome P450 aromatases.

    PubMed

    Gaucher, Eric A; Graddy, Logan G; Li, Tang; Simmen, Rosalia C M; Simmen, Frank A; Schreiber, David R; Liberles, David A; Janis, Christine M; Benner, Steven A

    2004-08-17

    Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. Here, we report an example of such an expansion, where tools from planetary biology were used to analyze three genes from the pig Sus scrofa that encode cytochrome P450 aromatases-enzymes that convert androgens into estrogens. The evolutionary history of the vertebrate aromatase gene family was reconstructed. Transition redundant exchange silent substitution metrics were used to interpolate dates for the divergence of family members, the paleontological record was consulted to identify changes in physiology that correlated in time with the change in molecular behavior, and new aromatase sequences from peccary were obtained. Metrics that detect changing function in proteins were then applied, including KA/KS values and those that exploit structural biology. These identified specific amino acid replacements that were associated with changing substrate and product specificity during the time of presumed adaptive change. The combined analysis suggests that aromatase paralogs arose in pigs as a result of selection for Suoidea with larger litters than their ancestors, and permitted the Suoidea to survive the global climatic trauma that began in the Eocene. This combination of bioinformatics analysis, molecular evolution, paleontology, cladistics, global climatology, structural biology, and organic chemistry serves as a paradigm in planetary biology. As the geological, paleontological, and genomic records improve, this approach should become widely useful to make systems biology statements about

  8. Mechanisms of Aromatase Inhibitor-induced Musculoskeletal Symptoms

    DTIC Science & Technology

    2012-07-01

    through the TRPV1 cation channel, an important chemical and thermal nociceptive transducer (15). In addition to steroids supplied by circulation in...identify whether aromatase expression co-localizes with functional neuronal populations, such as TRPV1 or CGRP expressing sensory neurons...to augment neuropeptide release from cultured sensory neurons evoked by the inflammatory mediator bradykinin and TRPV1 -selective agonist capsaicin (17

  9. Aromatase inhibitors: the next generation of therapeutics for endometriosis?

    PubMed

    Attar, Erkut; Bulun, Serdar E

    2006-05-01

    To review the role of aromatase inhibitors (AIs) in the treatment of endometriosis. Endometriosis is a common estrogen-dependent disorder that can result in substantial morbidity, including pelvic pain, multiple operations, and infertility. Approximately only half of women with endometriosis get pain relief from existing medical or surgical treatments. Medical treatments usually are directed at inhibiting estrogen action or its production from the ovaries and do not address local estrogen biosynthesis by the aromatase enzyme in endometriotic lesions. A single gene encodes aromatase, which is the final enzyme in the estrogen biosynthesis pathway, and its inhibition effectively eliminates estrogen production. The recently introduced highly specific AIs have successfully treated pelvic pain and significantly reduced the lesion size. In premenopausal women, an AI alone may induce ovarian folliculogenesis, and thus AIs are combined with a progestin, a combination oral contraceptive, or a GnRH analogue. The side-effect profile of AIs administered in combination with an oral contraceptive or a progestin is remarkably benign. We review herein the published clinical evidence for the use of AIs in the treatment of endometriosis.

  10. Enzymic aromatization of 6-alkyl-substituted androgens, potent competitive and mechanism-based inhibitors of aromatase.

    PubMed Central

    Numazawa, M; Yoshimura, A; Oshibe, M

    1998-01-01

    To gain insight into the relationships between the aromatase inhibitory activity of 6-alkyl-substituted androgens, potent competitive inhibitors, and their ability to serve as a substrate of aromatase, we studied the aromatization of a series of 6alpha- and 6beta-alkyl (methyl, ethyl, n-propyl, n-pentyl and n-heptyl)-substituted androst-4-ene-3,17-diones (ADs) and their androsta-1,4-diene-3,17-dione (ADD) derivatives with human placental aromatase, by gas chromatography-mass spectrometry. Among the inhibitors examined, ADD and its 6alpha-alkyl derivatives with alkyl functions less than three carbons long, together with 6beta-methyl ADD, are suicide substrates of aromatase. All of the steroids, except for 6beta-n-pentyl ADD and its n-heptyl analogue as well as 6beta-n-heptyl AD, were found to be converted into the corresponding 6-alkyl oestrogens. The 6-methyl steroids were aromatized most efficiently in each series, and the aromatization rate essentially decreased in proportion to the length of the 6-alkyl chains in each series, where the 6alpha-alkyl androgens were more efficient substrates than the corresponding 6beta isomers. The Vmax of 6alpha-methyl ADD was approx. 2.5-fold that of the natural substrate AD and approx. 3-fold that of the parent ADD. On the basis of this, along with the facts that the rates of a mechanism-based inactivation of aromatase by ADD and its 6alpha-methyl derivative are similar, it is implied that alignment of 6alpha-methyl ADD in the active site could favour the pathway leading to oestrogen over the inactivation pathway, compared with that of ADD. The relative apparent Km values for the androgens obtained in this study are different from the relative Ki values obtained previously, indicating that there is a difference between the ability to serve as an inhibitor and the ability to serve as a substrate in the 6-alkyl androgen series. PMID:9405288

  11. Computational Modeling to Evaluate Alternative Hypotheses for the Linkage of Aromatase Inhibition to Vitellogenin Levels in Fathead Minnows

    EPA Science Inventory

    Aromatase converts testosterone to estradiol (E2). In fish, E2 concentrations control hepatic synthesis of the glycolipoprotein vitellogenin (VTG), an egg yolk precursor protein essential to oocyte development and larval survival. Fathead minnows were exposed to the aromatase in...

  12. Synthesis and PET studies of [11C-cyano]letrozole (Femara®), an aromatase inhibitor drug

    PubMed Central

    Kil, Kun-Eek; Biegon, Anat; Ding, Yu-Shin; Fischer, Andre; Ferrieri, Richard A.; Kim, Sung Won; Pareto, Deborah; Schueller, Michael J.; Fowler, Joanna S.

    2011-01-01

    Introduction Aromatase, a member of the cytochrome P450 family, converts androgens such as androstenedione and testosterone to estrone and estradiol respectively. Letrozole (1-[bis-(4-cyanophenyl)methyl]-1H-1,2,4-triazole, Femara®) is a high affinity aromatase inhibitor (Ki=11.5 nM) which has FDA approval for breast cancer treatment. Here we report the synthesis of carbon-11 labeled letrozole and its assessment as a radiotracer for brain aromatase in the baboon. Methods Letrozole and its precursor (4-[(4-bromophenyl)-1H-1,2,4-triazol-1-ylmethyl]benzonitrile, 3) were prepared in two-step syntheses from 4-cyanobenzyl bromide and 4-bromobenzyl bromide, respectively. The [11C]cyano group was introduced via the tetrakis(triphenylphosphine)palladium(0) catalyzed coupling of [11C]cyanide with the bromo-precursor (3). PET studies in the baboon brain were carried out to assess regional distribution and kinetics, reproducibility of repeated measures and saturability. The free fraction of letrozole in the plasma, log D, and the [11C-cyano]letrozole fraction in the arterial plasma were also measured. Results [11C-cyano]Letrozole was synthesized in 60 min with a radiochemical yield of 79–80%, with a radiochemical purity greater than 98% and a specific activity of 4.16±2.21 Ci/μmol at the end of bombardment (n=4). PET studies in the baboon revealed initial rapid and high uptake and initial rapid clearance followed by slow clearance of carbon-11 from the brain with no difference between brain regions. The brain kinetics was not affected by co-injection of unlabeled letrozole (0.1 mg/kg). The free fraction of letrozole in plasma was 48.9% and log D was 1.84. Conclusion [11C-cyano]Letrozole is readily synthesized via a palladium catalyzed coupling reaction with [11C]cyanide. Although it is unsuitable as a PET radiotracer for brain aromatase as revealed by the absence of regional specificity and saturability in brain regions, such as amygdala, which are known to contain

  13. Oestrogen-deficient female aromatase knockout (ArKO) mice exhibit depressive-like symptomatology.

    PubMed

    Dalla, C; Antoniou, K; Papadopoulou-Daifoti, Z; Balthazart, J; Bakker, J

    2004-07-01

    We recently found that female aromatase knockout (ArKO) mice that are deficient in oestradiol due to a targeted mutation in the aromatase gene show deficits in sexual behaviour that cannot be corrected by adult treatment with oestrogens. We determined here whether these impairments are associated with changes in general levels of activity, anxiety or 'depressive-like' symptomatology due to chronic oestrogen deficiency. We also compared the neurochemical profile of ArKO and wild-type (WT) females, as oestrogens have been shown to modulate dopaminergic, serotonergic and noradrenergic brain activities. ArKO females did not differ from WT in spontaneous motor activity, exploration or anxiety. These findings are in line with the absence of major neurochemical alterations in hypothalamus, prefrontal cortex or striatum, which are involved in the expression of these behaviours. By contrast, ArKO females displayed decreased active behaviours, such as struggling and swimming, and increased passive behaviours, such as floating, in repeated sessions of the forced swim test, indicating that these females exhibit 'depressive-like' symptoms. Adult treatment with oestradiol did not reverse the behavioural deficits observed in the forced swim test, suggesting that they may be due to the absence of oestradiol during development. Accordingly, an increased serotonergic activity was observed in the hippocampus of ArKO females compared with WT, which was also not reversed by adult oestradiol treatment. The possible organizational role of oestradiol on the hippocampal serotonergic system and the 'depressive-like' profile of ArKO females provide new insights into the pathophysiology of depression and the increased vulnerability of women to depression.

  14. TGF-beta1 stimulates expression of the aromatase (CYP19) gene in human osteoblast-like cells and THP-1 cells.

    PubMed

    Shozu, M; Zhao, Y; Simpson, E R

    2000-02-25

    Recent evidence has shown that bone is not only a target of estrogen action but also a source of local estrogen production. Bone cells such as osteoblasts express aromatase (P450arom) and the expression of P450arom in osteoblasts is positively regulated in a tissue specific fashion, as in the case of other tissues which express P450arom. To clarify the physiological factors regulating expression of P450arom in bone, we tested TGF-beta1 using osteoblast-like cells obtained from human fetuses as well as THP-1 cells. TGF-beta1 increased IL-1beta+DEX- induced aromatase activity in osteoblast-like cells, while it inhibited activity in skin fibroblasts. Similar enhancement of aromatase activity by TGF-beta1 was found in DEX-stimulated THP-1 cells and this cell line was used for further experiments. In THP-1 cells, TGF-beta1 enhanced DEX-induced aromatase activity almost linearly by 12 h and thereafter. Increased levels of P450arom transcripts were also demonstrated by RT-PCR at 3 h of TGF-beta1 treatment and thereafter. Cyclohexamide abolished enhancement of activity but did not inhibit the accumulation of P450arom transcripts induced by TGF-beta1. Increase in P450arom expression by TGF-beta1 was attributable to expression driven by promoter I.4. TGF-beta1 did not change the half life of P450arom transcripts. To identify the cis-acting elements responsible for TGF-beta1 action on aromatase expression, transient transfection assays were performed using a series of deletion constructs for promoter I.4 (P450-I.4/Luc). Two constructs (-410/+14 and-340/+14) that contain a functional glucocorticoid response element (GRE) and downstream sequence showed significant increase of luciferase activity in response to TGF-beta1. Deletion and mutation of the GRE in P450-I.4/Luc (-340/+14) abolished the TGF-beta1. The luciferase activity of a (GRE)(1)-SV40/Luc construct was also stimulated by TGF-beta1. These results indicate that TGF-beta1 increases the expression of P450arom at the

  15. Analysis of the complex formation, interaction and electron transfer pathway between the "open" conformation of NADPH-cytochrome P450 reductase and aromatase.

    PubMed

    Dai, Yuejie; Zhen, Jing; Zhang, Xiuli; Zhong, Yonghui; Liu, Shaodan; Sun, Ziyue; Guo, Yue; Wu, Qingli

    2015-09-01

    The complex structure of human aromatase (CYP19) and the open form of ΔTGEE mutant NADPH-cytochrome P450 reductase (mCPR) was constructed using template-based protein alignment method. Dynamic simulation of formed complex was performed on NAMD 2.9, in which CHARMm all 27_prot_lipid_na force field and an explicit TIP3P water solvent model were applied. The result showed mCPR in its open conformation could steadily combine with aromatase from the proximal face. Data analysis indicates hydrogen bonds and four salt bridges on the binding surface enhance the interaction between the two protein molecules. Amino acid, Lys108 plays a key role in aromatase activity through the formation of a salt bridge with Asp147 and two hydrogen bonds with Asp147 and Gln150 in mCPR. The optimal pathway for the first electron transfer from CPR to aromatase was revealed and calculated using HARLEM software. The rates for solvent mediated and non-solvent mediated electron transfer from FMNH2 to heme were determined as 1.04×10(6)s(-)(1) and 4.86×10(5)s(-)(1) respectively, which indicates the solvent water can facilitate the electron transfer from FMNH2 to heme. This study presents a novel strategy for the study of the protein-protein interactions based on the template-based protein alignment, which may help new aromtase development targeting the electron transfer between mCPR and aromatase. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Potential utility of natural products as regulators of breast cancer-assoicated aromatase promoters

    USDA-ARS?s Scientific Manuscript database

    Aromatase, the key enzyme in estrogen biosynthesis, converts androstenedione to estrone and testosterone to estradiol. The enzyme is expressed in various tissues such as ovary, placenta, bone, brain, skin, and adipose tissue. Aromatase enzyme is encoded by a single gene CYP 19A1 and its expression i...

  17. Mechanism-based Categorization of Aromatase Inhibitors: A Potential Discovery and Screening Tool

    EPA Science Inventory

    Cytochrome P450 aromatase is a key steroidogenic enzyme that converts androgens to estrogens in vertebrates. There is much interest in aromatase inhibitors (AIs) because a number of environmental contaminants can act as AIs, thereby disrupting endocrine function in humans and wil...

  18. Integrated approach to explore the mechanisms of aromatase inhibition and recovery in fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Aromatase, a member of the cytochrome P450 superfamily, is a key enzyme in estradiol synthesis that catalyzes the aromatization of androgens into estrogens in ovaries. Here, we used an integrated approach to assess the mechanistic basis of the direct effects of aromatase inhibiti...

  19. Nicotine Blocks Brain Estrogen Synthase (Aromatase): In Vivo Positron Emission Tomography Studies in Female Baboons

    SciTech Connect

    Biegon, A.; Biegon, A.; Kim, S.-W.

    Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase. Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor [{sup 11}C]vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg. Nicotine administration produced significant, dose-dependent reductions in [{sup 11}C]vorozole binding. The amygdala and preoptic area showed the largestmore » reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers. Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior.« less

  20. The planetary biology of cytochrome P450 aromatases

    PubMed Central

    Gaucher, Eric A; Graddy, Logan G; Li, Tang; Simmen, Rosalia CM; Simmen, Frank A; Schreiber, David R; Liberles, David A; Janis, Christine M; Benner, Steven A

    2004-01-01

    Background Joining a model for the molecular evolution of a protein family to the paleontological and geological records (geobiology), and then to the chemical structures of substrates, products, and protein folds, is emerging as a broad strategy for generating hypotheses concerning function in a post-genomic world. This strategy expands systems biology to a planetary context, necessary for a notion of fitness to underlie (as it must) any discussion of function within a biomolecular system. Results Here, we report an example of such an expansion, where tools from planetary biology were used to analyze three genes from the pig Sus scrofa that encode cytochrome P450 aromatases–enzymes that convert androgens into estrogens. The evolutionary history of the vertebrate aromatase gene family was reconstructed. Transition redundant exchange silent substitution metrics were used to interpolate dates for the divergence of family members, the paleontological record was consulted to identify changes in physiology that correlated in time with the change in molecular behavior, and new aromatase sequences from peccary were obtained. Metrics that detect changing function in proteins were then applied, including KA/KS values and those that exploit structural biology. These identified specific amino acid replacements that were associated with changing substrate and product specificity during the time of presumed adaptive change. The combined analysis suggests that aromatase paralogs arose in pigs as a result of selection for Suoidea with larger litters than their ancestors, and permitted the Suoidea to survive the global climatic trauma that began in the Eocene. Conclusions This combination of bioinformatics analysis, molecular evolution, paleontology, cladistics, global climatology, structural biology, and organic chemistry serves as a paradigm in planetary biology. As the geological, paleontological, and genomic records improve, this approach should become widely useful to make

  1. Preparation of a novel antiserum to aromatase with high affinity and specificity: Its clinicopathological significance on breast cancer tissue.

    PubMed

    Kanomata, Naoki; Matsuura, Shiro; Nomura, Tsunehisa; Kurebayashi, Junichi; Mori, Taisuke; Kitawaki, Jo; Moriya, Takuya

    2017-01-01

    Aromatase inhibitors have been widely used for the endocrine treatment of estrogen-dependent breast cancer in postmenopausal patients. However, clinicopathological studies of aromatase have been limited due to unsatisfactory specificity and/or restricted availability of anti-aromatase antibodies. Here, we have generated a polyclonal antiserum with high affinity and specificity for human aromatase using a monoclonal antibody tagged immunoaffinity chromatography on an industrial production scale. Our preliminary immunohistochemical analysis of 221 invasive breast cancer cases indicated that 87.3% (193/221) had at least 5% aromatase positive cells. The histoscore for aromatase was inversely correlated with pT (p = 0.019), pN (p = 0.001), stage (p < 0.001), histologic grade (p = 0.003), lymphatic infiltration (p < 0.001), venous infiltration (p < 0.001), and Ki-67 index (p < 0.001). However, cancer aromatase expression was independent of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor 2 statuses. This antiserum will be applicable to clinicopathological examination of aromatase in addition to ER and PgR for an appropriate use of aromatase inhibitor on the treatment of breast cancer. Further studies on the relationship between Aromatase inhibitors have been widely used for the endocrine treatment of estrogen-dependent breast cancer in postmenopausal patients. However, clinicopathological studies of aromatase have been limited due to unsatisfactory specificity and/or restricted availability of anti-aromatase antibodies. Here, we have generated a polyclonal antiserum with high affinity and specificity for human aromatase using a monoclonal antibody tagged immunoaffinity chromatography on an industrial production scale. Our preliminary immunohistochemical analysis of 221 invasive breast cancer cases indicated that 87.3% (193/221) had at least 5% aromatase positive cells. The histoscore for aromatase was inversely correlated

  2. Merlin, the product of NF2 gene, is associated with aromatase expression and estrogen formation in human liver tissues and liver cancer cells.

    PubMed

    Cocciadiferro, Letizia; Miceli, Vitale; Granata, Orazia M; Carruba, Giuseppe

    2017-09-01

    The product of neurofibromatosis type 2 (NF2) gene, also known as Merlin/neurofibromin 2, homeostatically regulates liver stem cells by controlling abundance and signaling of epidermal growth factor receptor (EGFR), with a mechanism independent of the Hippo pathway. We have reported that locally elevated estrogen formation, driven by abnormally high expression and function of aromatase, may be implicated in development and progression of human hepatocellular carcinoma (HCC) through activation of a rapid signaling pathway mediated by amphiregulin (AREG) and EGFR. We have recently presented a model by which the aromatase-estrogen-amphiregulin-EGFR axis is activated in response to tissue injury and/or inflammatory disease, with its alteration eventually leading to development of major human tumors (liver, breast, prostate) and other chronic diseases (diabetes, obesity, Alzheimer's and heart disease). In this study, we investigated NF2 expression in liver cancer cells and tissues in relation to aromatase expression/function, estrogen receptor (ER) status and amphiregulin. Our data indicate that NF2 expression is associated with aromatase and AREG expression, being elevated in HCC tissues and HepG2 cells, intermediate in cirrhotic tissues and Huh7 cells, and lower in nontumoral liver and HA22T cells. In addition, NF2 expression is inversely related to wild type hERα66 and proportional to the expression of the membrane-associated hERα36 splice variant, as measured by exon-specific RT-PCR analysis, both in vivo and in vitro. Furthermore, incubation with estradiol induced a significant decrease of NF2 expression in both HA22T and Huh7 cells (over 54% and 22%, respectively), while no change could be observed in HepG2 cells, this effect being inversely related to aromatase expression and activity in HCC cell lines. Based on the above combined evidence, we hypothesize that NF2 behaves as a protein sensing tissue damage and aromatase-driven local estrogen formation

  3. Evaluation of a bioluminescent mouse model expressing aromatase PII-promoter-controlled luciferase as a tool for the study of endocrine disrupting chemicals

    SciTech Connect

    Rivest, Patricia, E-mail: patricia.rivest@iaf.inrs.ca; Devine, Patrick J., E-mail: patrick.devine@iaf.inrs.ca; Sanderson, J. Thomas, E-mail: thomas.sanderson@iaf.inrs.c

    Dysfunction of the enzyme aromatase (CYP19) is associated with endocrine pathologies such as osteoporosis, impaired fertility and development of hormone-dependent cancers. Certain endocrine disrupting chemicals affect aromatase expression and activity in vitro, but little is known about their ability to do so in vivo. We evaluated a bioluminescent mouse model (LPTA (registered)) CD-1-Tg(Cyp19-luc)-Xen) expressing luciferase under control of the gonadal aromatase pII promoter as an in vivo screening tool for chemicals that may affect aromatase expression. We studied the effects of forskolin, pregnant mare serum gonadotropin and atrazine in this model (atrazine was previously shown to induced pII-promoter-driven aromatase expressionmore » in H295R human adrenocortical carcinoma cells). About 2-4 out of every group of 10 male or female Cyp19-luc mice injected i.p. with 10 mg/kg forskolin had increased gonadal bioluminescence after 3-5 days compared to controls; the others appeared non-responsive. Similarly, about 4 per group of 9 individual females injected with pregnant mare serum gonadotropin had increased ovarian bioluminescence after 24 h. There was a statistically significant correlation between ovarian bioluminescence and plasma estradiol concentrations (n = 14; p = 0.022). Males exposed to a single dose of 100 mg/kg or males and females exposed to 5 daily injections of 30 mg/kg atrazine showed no change in gonadal bioluminescence over a 7 day period, but a significant interaction was found between atrazine (100 mg/kg) and time in female mice (p < 0.05; two-way ANOVA). Ex vivo luciferase activity in dissected organs was increased by forskolin in testis, epididymis and ovaries. Atrazine (30 mg/kg/day) increased (30%) luciferase activity significantly in epididymis only. In conclusion, certain individual Cyp19-luc mice are highly responsive to aromatase inducers, suggesting this model, with further optimization, may have potential as an in vivo screening tool

  4. Polymerase chain reaction amplification fails to detect aromatase cytochrome P450 transcripts in normal human endometrium or decidua.

    PubMed

    Bulun, S E; Mahendroo, M S; Simpson, E R

    1993-06-01

    It has been proposed that the biosynthesis of estrogens by the human endometrium may be of physiological significance during the menstrual cycle. Local estrogen production was also suggested to be important in the development of endometrial cancer; however, the presence or absence of aromatase enzyme activity in normal human endometrium is controversial. To address this issue, we used a sensitive technique capable of detecting mRNA transcripts present in only very low copy number. The polymerase chain reaction linked to reverse transcription (RT-PCR) was used to evaluate the presence or absence of aromatase cytochrome P450 (P450arom) transcripts in endometrial tissues (n = 7) and endometrial stromal cells (n = 9) under various culture conditions. RNA was isolated from four proliferative and three secretory tissue samples and from cultured endometrial stromal cells isolated from seven proliferative and two secretory endometria. Five sets of cultures were treated with medroxyprogesterone acetate (MPA), estradiol (E2), and forskolin. Additionally, RNA was isolated from decidualized endometrium obtained from a patient with tubal pregnancy. A single stranded cDNA was synthesized from total RNA using Moloney murine leukemia virus reverse transcriptase and a P450arom-specific oligonucleotide. The single stranded cDNA was used as a template for PCR and was amplified for 20-35 cycles using P450arom-specific primers. RNA from adipose tissue and placenta was amplified to provide positive controls, whereas myometrial RNA was used as a negative control. In two experiments involving two endometrial tissues and three sets of cells in culture, a rat P450arom cRNA was coamplified in each sample as an internal control to demonstrate that the remote possibility of RT-PCR failures in individual test samples cannot account for our negative results. By Southern or slot blot hybridization of the amplified fragments using human and rat P450arom-specific probes, we found no evidence for

  5. Differences between the non-steroidal aromatase inhibitors anastrozole and letrozole--of clinical importance?

    PubMed

    Geisler, J

    2011-03-29

    Aromatase inhibition is the gold standard for treatment of early and advanced breast cancer in postmenopausal women suffering from an estrogen receptor-positive disease. The currently established group of anti-aromatase compounds comprises two reversible aromatase inhibitors (anastrozole and letrozole) and on the other hand, the irreversible aromatase inactivator exemestane. Although exemestane is the only widely used aromatase inactivator at this stage, physicians very often have to choose between either anastrozole or letrozole in general practice. These third-generation aromatase inhibitors (letrozole/Femara (Novartis Pharmaceuticals, Basel, Switzerland) and anastrozole/Arimidex (AstraZeneca, Pharmaceuticals, Macclesfield, Cheshire, UK)), have recently demonstrated superior efficacy compared with tamoxifen as initial therapy for early breast cancer improving disease-free survival. However, although anastrozole and letrozole belong to the same pharmacological class of agents (triazoles), an increasing body of evidence suggests that these aromatase inhibitors are not equipotent when given in the clinically established doses. Preclinical and clinical evidence indicates distinct pharmacological profiles. Thus, this review focuses on the differences between the non-steroidal aromatase inhibitors allowing physicians to choose between these compounds based on scientific evidence. Although we are waiting for the important results of a still ongoing head-to-head comparison in patients with early breast cancer at high risk for relapse (Femara Anastrozole Clinical Evaluation trial; 'FACE-trial'), clinicians have to make their choices today. On the basis of available evidence summarised here and until FACE-data become available, letrozole seems to be the best choice for the majority of breast cancer patients whenever a non-steroidal aromatase inhibitor has to be chosen in a clinical setting. The background for this recommendation is discussed in the following chapters.

  6. Differences between the non-steroidal aromatase inhibitors anastrozole and letrozole – of clinical importance?

    PubMed Central

    Geisler, J

    2011-01-01

    Aromatase inhibition is the gold standard for treatment of early and advanced breast cancer in postmenopausal women suffering from an estrogen receptor-positive disease. The currently established group of anti-aromatase compounds comprises two reversible aromatase inhibitors (anastrozole and letrozole) and on the other hand, the irreversible aromatase inactivator exemestane. Although exemestane is the only widely used aromatase inactivator at this stage, physicians very often have to choose between either anastrozole or letrozole in general practice. These third-generation aromatase inhibitors (letrozole/Femara (Novartis Pharmaceuticals, Basel, Switzerland) and anastrozole/Arimidex (AstraZeneca, Pharmaceuticals, Macclesfield, Cheshire, UK)), have recently demonstrated superior efficacy compared with tamoxifen as initial therapy for early breast cancer improving disease-free survival. However, although anastrozole and letrozole belong to the same pharmacological class of agents (triazoles), an increasing body of evidence suggests that these aromatase inhibitors are not equipotent when given in the clinically established doses. Preclinical and clinical evidence indicates distinct pharmacological profiles. Thus, this review focuses on the differences between the non-steroidal aromatase inhibitors allowing physicians to choose between these compounds based on scientific evidence. Although we are waiting for the important results of a still ongoing head-to-head comparison in patients with early breast cancer at high risk for relapse (Femara Anastrozole Clinical Evaluation trial; ‘FACE-trial'), clinicians have to make their choices today. On the basis of available evidence summarised here and until FACE-data become available, letrozole seems to be the best choice for the majority of breast cancer patients whenever a non-steroidal aromatase inhibitor has to be chosen in a clinical setting. The background for this recommendation is discussed in the following chapters

  7. Long-term complete remission of metastatic breast cancer, induced by a steroidal aromatase inhibitor after failure of a non-steroidal aromatase inhibitor

    PubMed Central

    Shioi, Yoshihiro; Kashiwaba, Masahiro; Inaba, Toru; Komatsu, Hideaki; Sugai, Tamotsu; Wakabayashi, Go

    2014-01-01

    Patient: Female, 56 Final Diagnosis: Breast cancer Symptoms: Solid mass in the right breast Medication: Exemestane Clinical Procedure: — Specialty: Oncology Objective: Unusual clinical course Background: The efficacy of third-generation aromatase inhibitors for hormone receptor-positive postmenopausal metastatic breast cancer is well established. Although several clinical trials have reported incomplete cross-resistance between different aromatase inhibitors, few cases of complete responses of recurrent metastatic breast cancer occurring after substituting a second aromatase inhibitor have been reported. We here present a rare case of non-steroidal aromatase inhibitor-tolerant metastatic breast cancer with long-term complete remission following substitution of a steroidal aromatase inhibitor. Case Report: We present the case of a 56-year-old Japanese woman who underwent right breast-conserving surgery for breast cancer, TNM staging T1, N0, M0, Stage I. She received adjuvant chemotherapy with 6 cycles of FEC100 and radiation therapy, and then began hormonal therapy with anastrozole. Twelve months postoperatively, computed tomography (CT) revealed multiple lung metastases. Exemestane was substituted for anastrozole. After 3 months of exemestane, CT showed that all lung metastases had completely resolved. Her complete response was maintained for 5 years: she died during a tsunami 6 years after the initial surgery. Conclusions: Substitution of a steroidal for a non-steroidal aromatase inhibitor produced a sustained complete remission in a patient with hormonal receptor-positive postmenopausal recurrent breast cancer. Achieving complete response after switching from a non-steroidal to a steroidal aromatase inhibitor in a hormonal receptor-positive postmenopausal recurrent breast cancer contributed to a higher quality of life for the patient. Further investigation is needed to identify the predictors of long-term remission following such a switch. PMID:24587856

  8. Effect of β-agonist on the dexamethasone-induced expression of aromatase by the human monocyte cells

    PubMed Central

    Ohno, Shuji; Wachi, Hiroshi

    2017-01-01

    Emerging evidence suggests that sex steroids are important for human skin health. In particular, estrogen improves skin thickness, elasticity and moisture of older women. The major source of circulating estrogen is the ovary; however, local estrogen synthesis and secretion have important roles in, for example, bone metabolism and breast cancer development. We hypothesized that infiltrated peripheral monocytes are one of the sources of estrogen in skin tissues. We also hypothesized that, during atopic dermatitis under stress, a decline in the hypothalamus–pituitary–adrenal axis (HPA) and facilitation of the (hypothalamus)–sympathetic–adrenomedullary system (SAM) attenuates estrogen secretion from monocytes. Based on this hypothesis, we tested aromatase expression in the human peripheral monocyte-derived cell line THP-1 in response to the synthetic glucocorticoid dexamethasone (Dex), the synthetic β-agonist isoproterenol (Iso) and the β-antagonist propranolol (Pro). Dex mimics glucocorticoid secreted during excitation of the HPA, and Iso mimics catecholamine secreted during excitation of the SAM. We found that aromatase activity and the CYP19A1 gene transcript were both upregulated in THP-1 cells in the presence of Dex. Addition of Iso induced their downregulation and further addition of Pro rescued aromatase expression. These results may suggest that attenuation of estrogen secretion from peripheral monocytes could be a part of the pathology of stress-caused deterioration of atopic dermatitis. Further examination using an in vitro human skin model including THP-1 cells might be a valuable tool for investigating the therapeutic efficacy and mechanism of estrogen treatment for skin health. PMID:28126832

  9. Effect of β-agonist on the dexamethasone-induced expression of aromatase by the human monocyte cells.

    PubMed

    Watanabe, Masatada; Ohno, Shuji; Wachi, Hiroshi

    2017-02-01

    Emerging evidence suggests that sex steroids are important for human skin health. In particular, estrogen improves skin thickness, elasticity and moisture of older women. The major source of circulating estrogen is the ovary; however, local estrogen synthesis and secretion have important roles in, for example, bone metabolism and breast cancer development. We hypothesized that infiltrated peripheral monocytes are one of the sources of estrogen in skin tissues. We also hypothesized that, during atopic dermatitis under stress, a decline in the hypothalamus-pituitary-adrenal axis (HPA) and facilitation of the (hypothalamus)-sympathetic-adrenomedullary system (SAM) attenuates estrogen secretion from monocytes. Based on this hypothesis, we tested aromatase expression in the human peripheral monocyte-derived cell line THP-1 in response to the synthetic glucocorticoid dexamethasone (Dex), the synthetic β-agonist isoproterenol (Iso) and the β-antagonist propranolol (Pro). Dex mimics glucocorticoid secreted during excitation of the HPA, and Iso mimics catecholamine secreted during excitation of the SAM. We found that aromatase activity and the CYP19A1 gene transcript were both upregulated in THP-1 cells in the presence of Dex. Addition of Iso induced their downregulation and further addition of Pro rescued aromatase expression. These results may suggest that attenuation of estrogen secretion from peripheral monocytes could be a part of the pathology of stress-caused deterioration of atopic dermatitis. Further examination using an in vitro human skin model including THP-1 cells might be a valuable tool for investigating the therapeutic efficacy and mechanism of estrogen treatment for skin health. © 2017 The authors.

  10. Gonadal expression of aromatase and estrogen receptor alpha genes in two races of Tunisian mice and their hypofertile hybrids.

    PubMed

    Saïd, Lamia; Delalande, Christelle; Britton-Davidian, Janice; Saïd, Khaled; Saad, Ali; Carreau, Serge

    2007-07-01

    House mice (Mus musculus domesticus) in Tunisia consists of two races, one carries the 40-acrocentric standard karyotypes and the other one is a robertsonian race (2n=22) homozygous for nine centric fusions (Rb). The F1 hybrids between the two chromosomal races showed a significant decrease in reproductive success and litter size. Such results can be related to the formation of meiotic trivalent in the hybrids leading to the production of viable aneuploid gametes and post-zygotic elimination of embryos due to chromosomal non disjunction events at meiosis. Moreover, testicular histology of F1 and backcross males showed in some cases a breakdown in spermatogenesis. In both females and males, androgens but also estrogens play an important role in gametogenesis. In this study, we have studied aromatase and estrogen receptor alpha (ERalpha) gene expression in the gonads of the two parental races and their chromosomal hybrids. The results showed that aromatase and ERalpha mRNAs are expressed in hybrid males of inter-racial crosses (female22Rb x male40Std and female40Std x male22Rb) and in hybrid females of inter-racial crosses (female22Rb x male40Std) as in the two parental races. However, in hybrid females of inter-racial crosses (female40Std x male22Rb) the amount of aromatase transcripts decreased sharply suggesting that this gene is involved in the breakdown of hybrid fertility in females, but not in males. However, in hybrid males, a putative post-translational modification of this enzyme, in terms of activity, should be verified.

  11. Clinical Use of Aromatase Inhibitors in Adult Males.

    PubMed

    Tan, Ronny B W; Guay, Andre T; Hellstrom, Wayne J G

    2014-04-01

    There is a growing interest in the treatment of late-onset hypogonadism, another name for the study of testosterone deficiency in an older age group. Initial attempts at testosterone replacement have also brought attention to the possible adverse effects on the patients' cardiovascular risk factors and their prostate health. The "female" hormone estradiol is no longer considered as the feminizing hormone, as it has been identified to have an effect on the sexual and general well-being of adult males. Urologists and endocrinologists alike have started to pay attention to the serum T/E 2 (testosterone : estradiol) ratio that appears to be more important than the respective individual hormonal levels. Therein lies the possible role of aromatase inhibitors (AIs) in restoring the normal balance of serum testosterone and estradiol levels for the adequate treatment of late-onset hypogonadism, while limiting the potential adverse effects. Currently, other established clinical indications of AIs include the treatment of breast cancer in female patients and developmental growth problems in pediatric patients. This review evaluates the role of AIs as a treatment option for late-onset hypogonadism and the evidence for its other clinical uses in men, including its possible adverse effects. A literature review was performed with regards to the use of aromatase inhibitors in adult males, the role of estrogens in adult males, as well as adverse effect of AIs on bone health in adult males. To evaluate the evidence for the use of AIs in adult males to treat late-onset hypogonadism, obesity-related hypogonadotropic hypogonadism, gynecomastia, and male subfertility. To evaluate the evidence for the possible adverse effects on the bone health of adult males with the use of AIs. Currently there is no literature to recommend the use of AIs in adult males to treat late-onset hypogonadism, obesity-related hypogonadotropic hypogonadism, gynecomastia, or male subfertility, although some

  12. Hypervitaminosis A-induced liver fibrosis: stellate cell activation and daily dose consumption.

    PubMed

    Nollevaux, M-C; Guiot, Y; Horsmans, Y; Leclercq, I; Rahier, J; Geubel, A P; Sempoux, C

    2006-03-01

    Hypervitaminosis A-related liver toxicity may be severe and may even lead to cirrhosis. In the normal liver, vitamin A is stored in hepatic stellate cells (HSC), which are prone to becoming activated and acquiring a myofibroblast-like phenotype, producing large amounts of extracellular matrix. In order to assess the relationship between vitamin A intake, HSC activation and fibrosis, we studied nine liver biopsies from patients belonging to a well-characterized series of 41 patients with vitamin A hepatotoxicity. Fibrosis was underlined by Sirius-red staining, whereas activated HSC were immunohistochemically identified using an antibody against alpha smooth muscle actin. The volume density (Vv) of sinusoidal and total fibrosis and of sinusoidal and total activated HSC was quantified by the point-counting method. Morphology ranged from HSC hypertrophy and hyperplasia as the sole features to severe architectural distortion. There was a significant positive correlation between Vv of perisinusoidal fibrosis and the daily consumption of vitamin A (P=0.004). The close correlation between the severity of perisinusoidal fibrosis and the daily dose of the retinol intake suggests the existence of a dose-effect relationship.

  13. A Quantative Adverse Outcome Pathway Linking Aromatase Inhibition in Fathead Minnows with Population Dynamics

    EPA Science Inventory

    A Quantitative Adverse Outcome Pathway Linking Aromatase Inhibition in Fathead Minnows with Population DynamicsAn adverse outcome pathway (AOP) is a qualitative description linking a molecular initiating event (MIE) with measureable key events leading to an adverse outcome (AO). ...

  14. Use of Network Inference to Unravel the Mechanisms of Action and Specificity of Aromatase Inhibitors

    EPA Science Inventory

    The vertebrate hypothalamus-pituitary-gonadal (HPG) axis is controlled through various feedback mechanisms in order to maintain a dynamic homeostasis during changing environmental conditions, including exposure to chemical stressors. In this study, three aromatase inhibitors, fad...

  15. Transferrin-conjugated lipid-coated PLGA nanoparticles for targeted delivery of aromatase inhibitor 7alpha-APTADD to breast cancer cells.

    PubMed

    Zheng, Yu; Yu, Bo; Weecharangsan, Wanlop; Piao, Longzhu; Darby, Michael; Mao, Yicheng; Koynova, Rumiana; Yang, Xiaojuan; Li, Hong; Xu, Songlin; Lee, L James; Sugimoto, Yasuro; Brueggemeier, Robert W; Lee, Robert J

    2010-05-10

    Transferrin (Tf)-conjugated lipid-coated poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles carrying the aromatase inhibitor, 7alpha-(4'-amino)phenylthio-1,4-androstadiene-3,17-dione (7alpha-APTADD), were synthesized by a solvent injection method. Formulation parameters including PLGA-to-lipid, egg PC-to-TPGS, and drug-to-PLGA ratios and aqueous-to-organic phase ratio at the point of synthesis were optimized to obtain nanoparticles with desired sizes and drug loading efficiency. The optimal formulation had a drug loading efficiency of 36.3+/-3.4%, mean diameter of 170.3+/-7.6nm and zeta potential of -18.9+/-1.5mV. The aromatase inhibition activity of the nanoparticles was evaluated in SKBR-3 breast cancer cells. IC(50) value of the Tf-nanoparticles was ranging from 0.77 to 1.21nM, and IC(50) value of the nanoparticles was ranging from 1.90 to 3.41nM (n=3). The former is significantly lower than the latter (p<0.05). These results suggested that the aromatase inhibition activity of the Tf-nanoparticles was enhanced relative to that of the non-targeted nanoparticles, which was attributable to Tf receptor (TfR) mediated uptake. In conclusion, Tf-conjugated lipid-coated PLGA nanoparticles are potential vehicles for improving the efficiency and specificity of therapeutic delivery of aromatase inhibitors. Copyright 2010 Elsevier B.V. All rights reserved.

  16. Localization of the aromatase enzyme expression in the human pituitary gland and its effect on growth hormone, prolactin, and thyroid stimulating hormone axis.

    PubMed

    Caglar, Asli Sezgin; Kapucu, Aysegul; Dar, Kadriye Akgun; Ozkaya, Hande Mefkure; Caglar, Erkan; Ince, Haluk; Kadioglu, Pinar

    2015-08-01

    The aim of this study is to evaluate aromatase expression in prolactin (PRL), thyroid stimulating hormone (TSH), and growth hormone (GH) secreting cells. Nontumoral human pituitary specimens were obtained from autopsy samples. Aromatase co-expression was determined by double immunohistochemical staining and assessed using H scores. H scores for GH-aromatase co-expression (GH-aromatase), TSH-aromatase co-expression (TSH-aromatase), and PRL-aromatase co-expression (PRL-aromatase) were 83.1 ± 13.1, 95.6 ± 16.1, and 83.7 ± 14.5, respectively. TSH producing cells exhibited the highest H score for co-expression of aromatase (p < 0.001). There was no gender difference in terms of H scores for aromatase expression and double immunohistochemical staining results (p > 0.05 for all). There was a negative correlation between the H scores for aromatase and PRL-aromatase, GH-aromatase and TSH-aromatase, respectively (r = -0.592, p < 0.001; r = -0.593, p < 0.001; r = -0.650, p < 0.001, respectively). Also, H scores for aromatase co-expression of each hormone were negatively correlated with the H scores for the corresponding hormone (r = -0.503, p < 0.001 for PRL-aromatase and PRL; r = -0.470, p < 0.001 for GH-aromatase, and GH; r = -0.641, p < 0.001 for TSH-aromatase and TSH). H scores for mean aromatase, GH-aromatase, TSH-aromatase were invariant of age (p > 0.05 for all). Age was negatively correlated with PRL-aromatase H score (r = -0.373, p = 0.008). Our study demonstrated significant aromatase co-expression in PRL, GH, and TSH secreting cells of the human anterior pituitary gland. The mutual paracrinal regulation between aromatase and three adenohypophyseal hormones indicates that aromatase may have a regulatory role on the synthesis and secretion of these hormones.

  17. CoMFA, LeapFrog and blind docking studies on sulfonanilide derivatives acting as selective aromatase expression regulators.

    PubMed

    Gueto, Carlos; Torres, Juan; Vivas-Reyes, Ricardo

    2009-09-01

    Aromatase, the enzyme responsible for estrogen biosynthesis, is an attractive target in the treatment of hormone-dependent breast cancer. In this manuscript, the structure-based drug design approach of sulfonanilide analogues as potential selective aromatase expression regulators (SAERs) is described. Receptor-independent CoMFA (Comparative Molecular Field Analysis) maps were employed for generating a pseudocavity for LeapFrog calculation. A robust model, using 45 and 10 molecules in the training and test sets, respectively, was developed producing statistically significant results with cross-validated and conventional correlation coefficients of 0.656 and 0.956, respectively. This model was used to predict the activity of newly proposed molecules as SAERs candidates being two magnitude orders more potent than the previously reported compounds. Also in the present study, the computational blind docking method using eHiTS is tested on molecules study group and COX-2 enzyme. Future perspectives of the method in the screening of SAERs candidates with no COX-2 inhibitory activity are discussed.

  18. Forced expression of Hnf4a induces hepatic gene activation through directed differentiation.

    PubMed

    Yahoo, Neda; Pournasr, Behshad; Rostamzadeh, Jalal; Fathi, Fardin

    2016-08-05

    Embryonic stem (ES) cells are capable of unlimited self-renewal and have a diverse differentiation potential. These unique features make ES cells as an attractive source for developmental biology studies. Having the mature hepatocyte in the lab with functional activities is valuable in drug discovery studies. Overexpression of hepatocyte lineage-specific transcription factors (TFs) becomes a promising approach in pluripotent cell differentiation toward liver cells. Many studies generate transgenic ES cell lines to examine the effects of specific TFs overexpression in cell differentiation. In the present report, we have addressed whether a suspension or adherent model of differentiation is an appropriate way to study the role of Hnf4a overexpression. We generated ES cells that carried a doxycycline (Dox)-inducible Hnf4a using lentiviral vectors. The transduced cells were subjected to induced Hnf4a overexpression through both spontaneous and directed differentiation methods. Gene expression analysis showed substantially increased expression of hepatic gene markers, particularly Ttr and endogenous Hnf4a, in transduced cells differentiated by the directed approach. These results demonstrated that forced expression of TFs during directed differentiation would be an appropriate way to study relevant gene activation and the effects of overexpression in the context of hepatic differentiation. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. EFFECTS OF METHYLTESTOSTERONE ON AROMATASE ACTIVITY IN ADULT FATHEAD MINNOW

    EPA Science Inventory

    The effect of methyltestosterone (MT) in a fathead minnow 21-d reproduction assay was previously determined in this laboratory. It was found that methyltestosterone at 0.2 and 2 mg/L produced both estreogenic and androgenic effects. Both concentrations of methyltestosterone produ...

  20. EFFECTS OF METHYLTOSTERONE ON AROMATASE ACTIVITY IN ADULT FATHEAD MINNOW

    EPA Science Inventory

    The effect of methyltestosterone (MT) in a fathead minnow 21-d reproduction assay was previously determined in this laboratory. It was found that methyltestosterone at 0.2 and 2 mg/L produced both estrogenic and androgenic effects. Both concentrations of methyltestosterone produc...

  1. Tall stature without growth hormone: four male patients with aromatase deficiency.

    PubMed

    Rochira, Vincenzo; Zirilli, Lucia; Maffei, Laura; Premrou, Valeria; Aranda, Claudio; Baldi, Matteo; Ghigo, Ezio; Aimaretti, Gianluca; Carani, Cesare; Lanfranco, Fabio

    2010-04-01

    From preliminary observations, GH-IGF-I seems to be compromised in men with aromatase deficiency. The GH deficiency (GHD) coexists paradoxically with tall stature, raising the question whether or not a true GHD is part of this rare syndrome. To evaluate the GH secretion in aromatase-deficient men, their GH response to the GHRH plus arginine (GHRH-ARG) test was compared with that of normal subjects. The effect of estrogen replacement treatment on the GH-IGF-I axis in aromatase-deficient men was evaluated before and during therapy. A case-control study was conducted. Four adult men with aromatase deficiency were compared with 12 normal subjects. We measured the GH response to GHRH-ARG in aromatase-deficient men (at baseline and during estrogen treatment) and in normal subjects. Basal serum IGF-I was measured in both patients and controls. The response of GH to GHRH-ARG was severely impaired in men with aromatase deficiency and resulted in significantly lower (P < 0.001) levels than in normal subjects. Although normal, serum IGF-I levels were also significantly lower (P < 0.001) than in normal subjects. Both GH peak and IGF-I concentrations were not modified by estrogen therapy in men with aromatase deficiency. In aromatase-deficient men, GH response to potent provocative stimuli is impaired and is not restored by exogenous estrogens. Furthermore, a tall stature may be reached, notwithstanding the coexistence of GHD, if a prolonged time for growth is available due to a delay in bone maturation, and other growth factors different from GH (mainly insulin) promote growth.

  2. Cirmtuzumab inhibits Wnt5a-induced Rac1 activation in chronic lymphocytic leukemia treated with ibrutinib

    PubMed Central

    Yu, J; Chen, L; Cui, B; Wu, Christina; Choi, M Y; Chen, Y; Zhang, L; Rassenti, L Z; Widhopf II, G F; Kipps, T J

    2017-01-01

    Signaling via the B cell receptor (BCR) plays an important role in the pathogenesis and progression of chronic lymphocytic leukemia (CLL). This is underscored by the clinical effectiveness of ibrutinib, an inhibitor of Bruton's tyrosine kinase (BTK) that can block BCR-signaling. However, ibrutinib cannot induce complete responses (CR) or durable remissions without continued therapy, suggesting alternative pathways also contribute to CLL growth/survival that are independent of BCR-signaling. ROR1 is a receptor for Wnt5a, which can promote activation of Rac1 to enhance CLL-cell proliferation and survival. In this study, we found that CLL cells of patients treated with ibrutinib had activated Rac1. Moreover, Wnt5a could induce Rac1 activation and enhance proliferation of CLL cells treated with ibrutinib at concentrations that were effective in completely inhibiting BTK and BCR-signaling. Wnt5a-induced Rac1 activation could be blocked by cirmtuzumab (UC-961), an anti-ROR1 mAb. We found that treatment with cirmtuzumab and ibrutinib was significantly more effective than treatment with either agent alone in clearing leukemia cells in vivo. This study indicates that cirmtuzumab may enhance the activity of ibrutinib in the treatment of patients with CLL or other ROR1+ B-cell malignancies. PMID:27904138

  3. Cirmtuzumab inhibits Wnt5a-induced Rac1 activation in chronic lymphocytic leukemia treated with ibrutinib.

    PubMed

    Yu, J; Chen, L; Cui, B; Wu, Christina; Choi, M Y; Chen, Y; Zhang, L; Rassenti, L Z; Widhopf Ii, G F; Kipps, T J

    2017-06-01

    Signaling via the B cell receptor (BCR) plays an important role in the pathogenesis and progression of chronic lymphocytic leukemia (CLL). This is underscored by the clinical effectiveness of ibrutinib, an inhibitor of Bruton's tyrosine kinase (BTK) that can block BCR-signaling. However, ibrutinib cannot induce complete responses (CR) or durable remissions without continued therapy, suggesting alternative pathways also contribute to CLL growth/survival that are independent of BCR-signaling. ROR1 is a receptor for Wnt5a, which can promote activation of Rac1 to enhance CLL-cell proliferation and survival. In this study, we found that CLL cells of patients treated with ibrutinib had activated Rac1. Moreover, Wnt5a could induce Rac1 activation and enhance proliferation of CLL cells treated with ibrutinib at concentrations that were effective in completely inhibiting BTK and BCR-signaling. Wnt5a-induced Rac1 activation could be blocked by cirmtuzumab (UC-961), an anti-ROR1 mAb. We found that treatment with cirmtuzumab and ibrutinib was significantly more effective than treatment with either agent alone in clearing leukemia cells in vivo. This study indicates that cirmtuzumab may enhance the activity of ibrutinib in the treatment of patients with CLL or other ROR1 + B-cell malignancies.

  4. Several synthetic progestins disrupt the glial cell specific-brain aromatase expression in developing zebra fish

    SciTech Connect

    Cano-Nicolau, Joel

    The effects of some progestins on fish reproduction have been recently reported revealing the hazard of this class of steroidal pharmaceuticals. However, their effects at the central nervous system level have been poorly studied until now. Notwithstanding, progesterone, although still widely considered primarily a sex hormone, is an important agent affecting many central nervous system functions. Herein, we investigated the effects of a large set of synthetic ligands of the nuclear progesterone receptor on the glial-specific expression of the zebrafish brain aromatase (cyp19a1b) using zebrafish mechanism-based assays. Progesterone and 24 progestins were first screened on transgenic cyp19a1b-GFP zebrafish embryos. Wemore » showed that progesterone, dydrogesterone, drospirenone and all the progesterone-derived progestins had no effect on GFP expression. Conversely, all progestins derived from 19-nortesterone induced GFP in a concentration-dependent manner with EC{sub 50} ranging from the low nM range to hundreds nM. The 19-nortestosterone derived progestins levonorgestrel (LNG) and norethindrone (NET) were further tested in a radial glial cell context using U251-MG cells co-transfected with zebrafish ER subtypes (zfERα, zfERβ1 or zfERβ2) and cyp19a1b promoter linked to luciferase. Progesterone had no effect on luciferase activity while NET and LNG induced luciferase activity that was blocked by ICI 182,780. Zebrafish-ERs competition assays showed that NET and LNG were unable to bind to ERs, suggesting that the effects of these compounds on cyp19a1b require metabolic activation prior to elicit estrogenic activity. Overall, we demonstrate that 19-nortestosterone derived progestins elicit estrogenic activity by inducing cyp19a1b expression in radial glial cells. Given the crucial role of radial glial cells and neuro-estrogens in early development of brain, the consequences of exposure of fish to these compounds require further investigation. - Highlights: • P4

  5. Aromatase expression is linked to estrogenic sensitivity of periurethral muscles in female rabbits.

    PubMed

    de los Ángeles Carrasco-Ruiz, María; García-Villamar, Verónica; López-García, Kenia; Sánchez-García, Octavio; Pacheco, Pablo; Cuevas, Estela; Martínez-Gómez, Margarita; Castelán, Francisco

    2015-06-01

    Beyond its role in the conversion of androgens to estrogens, the expression of aromatase could influence on the estrogenic signalling in targeted tissues. Considering the well-defined biochemical and physiological differences between the pubococcygeus (Pcm) and bulbospongiosus (Bsm) muscles in female rabbits, it is presently hypothesized that the aromatase expression is differentially linked to the estrogen sensitivity of each muscle. To this end, serum estradiol levels and the aromatase expression, presence of ERα and ERβ and morphometry were evaluated in the Pcm and Bsm of female rabbits allocated in control, ovariectomized (OVX) and OVX treated with estradiol benzoate (OVX + EB) groups. Aromatase expression was high in the Pcm. Independently to serum estradiol, ovariectomy increased aromatase expression in the Pcm while decreased it in the Bsm. The EB treatment avoided the effect of ovariectomy only in the Pcm. The number of immunoreactive nuclei anti-ERα and anti-ERβ was high in the Pcm of OVX and OVX + EB rabbits, while those in the Bsm remained unchanged. The number of peripheral nuclei per fibre and the cross-sectional area-to-myonucleus ratio were modified only in the Pcm. Our findings support aromatase expression in the Pcm, and Bsm of rabbits is differentially linked to estrogenic sensitivity of each muscle. Copyright © 2015 John Wiley & Sons, Ltd.

  6. Concanavalin A-induced and spontaneous suppressor cell activities in peripheral blood lymphocytes and spleen cells from gastric cancer patients.

    PubMed

    Toge, T; Hamamoto, S; Itagaki, E; Yajima, K; Tanada, M; Nakane, H; Kohno, H; Nakanishi, K; Hattori, T

    1983-11-01

    In 173 gastric cancer patients, activities of Concanavalin-A-induced suppressor cells (Con-AS) and spontaneous suppressor cells (SpS) in peripheral blood lymphocytes (PBL), splenic vein lymphocytes (SVL), and spleen cells (SCs) were investigated. Suppressions by Con-AS in PBL were significantly effective in patients of Stages III and IV, while suppressions by SpS were effective in patients with recurrent tumors. Thus, in PBLs of cancer patients, suppressor precursors, which are considered to be activated in vitro by Concanavalin-A, seemed to appear with the advances of the disease, and SpS activities, which could be already activated in vivo, seemed to increase in the terminal stage. In SCs, increased activities of Con-AS, but normal activities of SpS, were observed, and these suppressor-cell populations consisted of glass nonadherent cells. Suppressor activities of SCs would be due to suppressor T-cells, not to other types of cells. Furthermore, Con-AS existed in the medium-sized lymphocytes, which were fractionated on the basis of cell size, while SpS in the large-sized lymphocytes. A higher proportion of T-cells, bearing Fc receptors for IgG, was observed in the larger-sized lymphocyte fractions. Cell numbers in the large-sized lymphocyte fraction tended to increase with the advances of tumors. From these results, it is suggested that higher presence of suppressor precursors and the increase of SpS activities may occur in cancer patients, depending on the tumor advancing.

  7. Idiopathic hirsutism: local and peripheral expression of aromatase (CYP19A) and 5α-reductase genes (SRD5A1 and SRD5A2).

    PubMed

    Caglayan, A Okay; Dundar, Munis; Tanriverdi, Fatih; Baysal, Nuran A; Unluhizarci, Kursad; Ozkul, Yusuf; Borlu, Murat; Batukan, Cem; Kelestimur, Fahrettin

    2011-08-01

    To evaluate idiopathic hirsutism etiology via molecular studies testing peripheral and local aromatase and 5α-reductase expression. Assessment of the expression of messenger RNA (mRNA) for type 1 and 2,5α-reductase isoenzyme gene (SDR5A1, SDR5A2) and aromatase (CYP19A) in dermal papillae cells and peripheral blood mononuclear cells. University hospital. 28 untreated idiopathic hirsute patients and 20 healthy women (controls). Human skin biopsies and peripheral venous blood. SDR5A1, SDR5A2, CYP19A gene expression in skin biopsies and peripheral blood. A statistically significant reduction of SRD5A1, SRD5A2, and CYP19A gene expression was found in the dermal papillae cells and peripheral blood mononuclear cell between the study and control group. Further study, including protein expression and enzyme activity assays, are warranted to characterize the paradoxically low gene expression levels of local 5α-reductase and aromatase in women with idiopathic hirsutism. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Disruptions in aromatase expression in the brain, reproductive behavior, and secondary sexual characteristics in male guppies (Poecilia reticulata) induced by tributyltin.

    PubMed

    Tian, Hua; Wu, Peng; Wang, Wei; Ru, Shaoguo

    2015-05-01

    Although bioaccumulation of tributyltin (TBT) in fish has been confirmed, information on possible effects of TBT on reproductive system of fish is still relatively scarce, particularly at environmentally relevant levels. To evaluate the adverse effects and intrinsic toxicological properties of TBT in male fish, we studied aromatase gene expression in the brain, sex steroid contents, primary and secondary sexual characteristics, and reproductive behavior in male guppies (Poecilia reticulata) exposed to tributyltin chloride at the nominal concentrations of 5, 50, and 500 ng/L for 28 days in a semi-static exposure system. Radioimmunoassay demonstrated that treatment with 50 ng/L TBT caused an increase in systemic levels of testosterone of male guppies. Gonopodial index, which showed a positive correlation with testosterone levels, was elevated in the 5 ng/L and 50 ng/L TBT treated groups. Real-time PCR revealed that TBT exposure had inhibiting effects on expression of two isoforms of guppy aromatase in the brain, and these changes at the molecular levels were associated with a disturbance of reproductive behavior of the individuals, as measured by decreases in frequencies of posturing, sigmoid display, and chase activities when males were paired with females. This study provides the first evidence that TBT can cause abnormalities of secondary sexual characteristics in teleosts and that suppression of reproductive behavior in teleosts by TBT is due to its endocrine-disrupting action as an aromatase inhibitor targeting the nervous system. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Role of oestrogen in male sexual behaviour: insights from the natural model of aromatase deficiency.

    PubMed

    Carani, C; Rochira, V; Faustini-Fustini, M; Balestrieri, A; Granata, A R

    1999-10-01

    In order to evaluate the role of oestrogens on human male sexual behaviour, the gender-identity, psychosexual orientation and sexual activity of a man with a congenital lack of oestradiol resulting from an inactivating mutation of the aromatase P450 gene was investigated. The psychosexual and sexual behavioural evaluations were performed before and during testosterone treatment and before oestradiol treatment, during three phases of different dosages of oestradiol treatment. The study was performed before (phase A) and during (phase B) testosterone enanthate treatment (250 mg i.m. every 10 days, for 6 months), during testosterone withdrawal (phase C), and during each of the following transdermal oestradiol treatments: 50 microg twice a week for 6 months (phase D); 25 microg twice a week for 9 months (phase E), and 12.5 microg twice a week for 9 months (phase F). Sexual behaviour was investigated by a sexological interview and by a 2-month self-reported daily diary performed during each phase of the protocol study. Furthermore, during each oestradiol treatment (phase C, D, E and F), a study of depression, anxiety trait and sexual behaviour was performed by the Beck Depression Inventory (BDI), the Spielberger Trait Anxiety Inventory (STAI) and the Golombok-Rust Inventory of Sexual Satisfaction (GRISS), respectively. Sexual orientation and gender-identity were evaluated by the BEM Sex Role Inventory (BSRI). Serum testosterone and oestradiol were measured during each phase of the study. Before oestradiol treatment (phase C), serum oestradiol was undetectable, while it rose to 356.1, 88.1 and 55.1 pmol/l during phases D, E and F, respectively. Before any oestradiol treatment, during phase D, phase E and phase F serum testosterone was 18.13, 0.72, 14.3 and 18.51 nmol/l, respectively. The patient's gender-identity as assessed by BSRI and by the sexological interview was clearly male. The psychosexual orientation evaluated by BSRI, by the sexological interview and by the

  10. Aromatase inhibitors for subfertile women with polycystic ovary syndrome.

    PubMed

    Franik, Sebastian; Kremer, Jan A M; Nelen, Willianne L D M; Farquhar, Cindy

    2014-02-24

    Polycystic ovary syndrome (PCOS) is the most common cause of infrequent periods (oligomenorrhoea) and absence of periods (amenorrhoea). It affects about 4% to 8% of women worldwide and often leads to anovulatory subfertility. Aromatase inhibitors (AIs) are a novel class of drugs that were introduced for ovulation induction in 2001. Over the last ten years clinical trials have reached differing conclusions as to whether the AI letrozole is at least as effective as the first-line treatment clomiphene citrate (CC). To evaluate the effectiveness and safety of aromatase inhibitors for subfertile women with anovulatory PCOS. We searched the following sources from inception to 24/10/2013 to identify relevant randomised controlled trials (RCTs): the Menstrual Disorders and Subfertility Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PsycINFO, Pubmed, LILACS, Web of Knowledge, the World Health Organisation (WHO) clinical trials register and Clinicaltrials.gov. Furthermore, we manually searched the references of relevant articles.The search was not restricted by language or publication status. We included all RCTs of aromatase inhibitors used alone or with other medical therapies for ovulation induction in women of reproductive age with anovulatory PCOS. Two review authors independently selected trials, extracted the data and assessed trial quality. Studies were pooled where appropriate using a fixed effect model to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs) for most outcomes and risk differences (RDs) for ovarian hyperstimulation syndrome (OHSS). The primary outcomes were live birth and OHSS. Secondary outcomes were pregnancy, miscarriage and multiple pregnancy. The quality of the evidence for each comparison was assessed using GRADE methods. We included 26 RCTs (5560 women). In all studies the aromatase inhibitor was letrozole. Live birth (12 RCTs) One RCT compared letrozole with placebo in women

  11. Survival benefit of zoledronic Acid in postmenopausal breast cancer patients receiving aromatase inhibitors.

    PubMed

    Ahn, Sung Gwe; Kim, Sung Hyun; Lee, Hak Min; Lee, Seung Ah; Jeong, Joon

    2014-12-01

    A growing body of evidence indicates that zoledronic acid (ZA) can improve the clinical outcome in patients with breast cancer and low estrogen levels. In the present study, we aimed to investigate the survival benefit of ZA administration in postmenopausal Korean women with breast cancer who were also receiving aromatase inhibitors. Between January 2004 and December 2010, 235 postmenopausal breast cancer patients undergoing aromatase inhibitor therapy were investigated. All patients were postmenopausal, as confirmed by laboratory tests. Of these patients, 77 received adjuvant upfront ZA for at least 1 year in addition to conventional adjuvant treatment. The remaining 158 patients never received ZA and were treated according to the St. Gallen guidelines. The baseline characteristics for ZA treatment were not different between the two groups. The median follow-up time was 62 months, and the patients who received ZA in addition to aromatase inhibitors showed a better recurrence-free survival compared to those who received aromatase inhibitors alone (p=0.035). On multivariate analysis, the patients who received ZA showed a better recurrence-free survival independent of the tumor size, nodal status, progesterone receptor, and histological grade. For this model, Harrell c index was 0.743. The hazard ratio of ZA use for recurrence-free survival was 0.12 (95% confidence interval, 0.01-0.99). Our findings suggest that upfront use of ZA as part of adjuvant treatment can offer a survival benefit to postmenopausal breast cancer patients receiving aromatase inhibitor treatment.

  12. Expression and regulation of aromatase cytochrome P450 in THP 1 human myeloid leukaemia cells.

    PubMed

    Jakob, F; Homann, D; Seufert, J; Schneider, D; Köhrle, J

    1995-04-28

    Aromatase cytochrome P450 mRNA and activity was strongly expressed in THP 1 myeloid leukaemia cells after treatment with phorbol-myristate-acetate (PMA) and dexamethasone, low level expression was caused by calcitriol. mRNA species of 4.0, 3.0, 2.4 and 1.1 kb size were differentially stimulated. After calcitriol-mediated differentiation (72 h, measured by CD 14 expression) mRNA expression was further enhanced by PMA (45-fold), dexamethasone (15-fold), oestradiol (3.7-fold), testosterone (2.5-fold) and androstenedione (3.5-fold). Forskolin, cAMP and follicle stimulating hormone had no stimulatory effect. Oestradiol formation from testosterone (oestradiol radioimmunoassay in culture supernatants) increased to > 2000 pg/ml/10(6) cells/24 h after PMA-stimulation, mirrored mRNA expression and was suppressed below 10% of original values in the presence of 4-OH-androstenedione. Exons I.2 and I.4 were expressed in PMA-stimulated cells only, exon I.3 in both PMA- and dexamethasone-stimulated cells. A new splicing variant was expressed after calcitriol-stimulation, which did not hybridize to an exon II-derived oligonucleotide but to an exon III-derived one. Local aromatisation of androgens into oestradiol may be important in the concerted crosstalk of cells of the monocyte/macrophage lineage with their respective tissues in inflammation and bone metabolism.

  13. 3D-QSAR Study of Steroidal and Azaheterocyclic Human Aromatase Inhibitors using Quantitative Profile of Protein-Ligand Interactions

    EPA Science Inventory

    Aromatase is a member of the cytochrome P450 superfamily responsible for a key step in the biosynthesis of estrogens. As estrogens are involved in the control of important reproduction-related processes, including sexual differentiation and maturation, aromatase is a potential ta...

  14. Big enough for an aromatase inhibitor? How adiposity affects male fertility.

    PubMed

    Stephens, Sahar M; Polotsky, Alex J

    2013-07-01

    Obesity is a pandemic and is associated with multiple medical problems including subfertility. Male obesity has been associated with altered semen parameters and reproductive hormonal levels, including a reduced testosterone:estradiol (T:E₂) ratio. Treatment methods employed for obesity-related male subfertility include gonadotropin administration, weight loss, and aromatase inhibitors. Letrozole is a highly effective nonsteroidal aromatase inhibitor that has been used to treat male subfertility in several case series with promising results. Adequately designed randomized controlled studies are needed to produce evidence-based data on the role of aromatase inhibitors in male subfertility management and evaluate the side-effect profile. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. Nordic Walking as an Exercise Intervention to Reduce Pain in Women With Aromatase Inhibitor-Associated Arthralgia: A Feasibility Study.

    PubMed

    Fields, Jo; Richardson, Alison; Hopkinson, Jane; Fenlon, Deborah

    2016-10-01

    Women taking aromatase inhibitors as treatment for breast cancer commonly experience joint pain and stiffness (aromatase inhibitor-associated arthralgia [AIAA]), which can cause problems with adherence. There is evidence that exercise might be helpful, and Nordic walking could reduce joint pain compared to normal walking. To determine the feasibility of a trial of Nordic walking as an exercise intervention for women with AIAA. A feasibility study was carried out in a sample of women with AIAA using a randomized control design. Women were randomized to exercise (six-week supervised group Nordic walking training once per week with an increasing independent element, followed by six weeks 4 × 30 minutes/week independent Nordic walking); or enhanced usual care. Data were collected on recruitment, retention, exercise adherence, safety, and acceptability. The Brief Pain Inventory, GP Physical Activity Questionnaire, and biopsychosocial measures were completed at baseline, six and 12 weeks. Forty of 159 eligible women were recruited and attrition was 10%. There was no increased lymphedema and no long-term or serious injury. Adherence was >90% for weekly supervised group Nordic walking, and during independent Nordic walking, >80% women managed one to two Nordic walking sessions per week. From baseline to study end point, overall activity levels increased and pain reduced in both the intervention and control groups. Our findings indicate that women with AIAA are prepared to take up Nordic walking, complete a six-week supervised course and maintain increased activity levels over a 12-week period with no adverse effects. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  16. Aromatase inhibitors (letrozole) for subfertile women with polycystic ovary syndrome.

    PubMed

    Franik, Sebastian; Eltrop, Stephanie M; Kremer, Jan Am; Kiesel, Ludwig; Farquhar, Cindy

    2018-05-24

    Polycystic ovary syndrome (PCOS) is the most common cause of infrequent periods (oligomenorrhoea) and absence of periods (amenorrhoea). It affects about 4% to 8% of women worldwide and often leads to anovulatory subfertility. Aromatase inhibitors (AIs) are a class of drugs that were introduced for ovulation induction in 2001. Since about 2001 clinical trials have reached differing conclusions as to whether the AI letrozole is at least as effective as the first-line treatment clomiphene citrate (CC). To evaluate the effectiveness and safety of aromatase inhibitors for subfertile women with anovulatory PCOS for ovulation induction followed by timed intercourse or intrauterine insemination (IUI). We searched the following sources from inception to November 2017 to identify relevant randomised controlled trials (RCTs): the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, PsycINFO, Pubmed, LILACS, Web of Knowledge, the World Health Organization (WHO) clinical trials register and Clinicaltrials.gov. We also searched the references of relevant articles. We did not restrict the searches by language or publication status. We included all RCTs of AIs used alone or with other medical therapies for ovulation induction in women of reproductive age with anovulatory PCOS. Two review authors independently selected trials, extracted the data and assessed risks of bias. We pooled studies where appropriate using a fixed-effect model to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for most outcomes, and risk differences (RDs) for ovarian hyperstimulation syndrome (OHSS). The primary outcomes were live birth and OHSS. Secondary outcomes were clinical pregnancy, miscarriage and multiple pregnancy. We assessed the quality of the evidence for each comparison using GRADE methods. This is a substantive update of a previous review. We identified 16 additional studies for the 2018 update. We

  17. Brain aromatase and circulating corticosterone are rapidly regulated by combined acute stress and sexual interaction in a sex specific manner

    PubMed Central

    Dickens, M.J.; Balthazart, J.; Cornil, C. A.

    2012-01-01

    Neural production of 17β-oestradiol via aromatisation of testosterone may play a critical role in rapid, non-genomic regulation of physiological and behavioural processes. In brain nuclei implicated in the control of sexual behaviour, sexual or stressfull stimuli induce respectively a rapid inhibition or increase in preoptic aromatase activity (AA). Here, we tested quail that were either non-stressed or acutely stressed (15 min restraint) immediately prior to sexual interaction (5 min) with stressed or non-stressed partners. We measured nuclei-specific AA changes, corresponding behavioural output, fertilisation rates and corticosterone (CORT) concentrations. In males, sexual interaction rapidly reversed stress-induced increases of AA in the medial preoptic nucleus (POM). This time scale (<5min) highlights the dynamic potential of the aromatase system to integrate input from stimuli that drive AA in opposing directions. Moreover, acute stress had minimal effects on male behaviour suggesting that the input from the sexual stimuli on POM AA may actively preserve sexual behaviour despite stress exposure. We also found distinct sex differences in contextual physiological responses: while males did not show any effect of partner status, females responded to both their stress exposure and the male partner’s stress exposure at the level of circulating CORT and AA. In addition, fertilisation rates and female CORT correlated with the male partner’s exhibition of sexually aggressive behaviour suggesting that female perception of the male can affect their physiology as much as direct stress. Overall, male reproduction appears relatively simple – sexual stimuli, irrespective of stress, drives major neural changes including rapid reversal of stress-induced changes of AA. In contrast, female reproduction appears more nuanced and context specific, with subjects responding physiologically and behaviourally to stress, the male partner’s stress exposure, and female

  18. Aromatase up-regulation, insulin and raised intracellular oestrogens in men, induce adiposity, metabolic syndrome and prostate disease, via aberrant ER-α and GPER signalling.

    PubMed

    Williams, Graeme

    2012-04-04

    For some years now, reduced testosterone levels have been related to obesity, insulin resistance, type 2 diabetes, heart disease, benign prostatic hypertrophy and even prostate cancer--often considered guilty more by association, than actual cause--with little attention paid to the important role of increased intracellular oestrogen, in the pathogenesis of these chronic diseases. In the final stage of the steroidogenic cascade, testosterone is metabolised to oestradiol by P450 aromatase, in the cytoplasm of adipocytes, breast cells, endothelial cells and prostate cells, to increase intracellular oestradiol concentration at the expense of testosterone. It follows therefore, that any compound that up-regulates aromatase, or any molecule that mimics oestrogen, will not only increase the activation of the mainly proliferative, classic ER-α, oestrogen receptors to induce adipogenesis and growth disorders in oestrogen-sensitive tissues, but also activate the recently identified transmembrane G protein-coupled oestrogen receptors (GPER), and deleteriously alter important intracellular signalling sequences, that promote mitogenic growth and endothelial damage. This paper simplifies how stress, xeno-oestrogens, poor dietary choices and reactive toxins up-regulate aromatase to increase intracellular oestradiol production; how oestradiol in combination with leptin and insulin cause insulin resistance and leptin resistance through aberrant serine phosphorylation; how the increased oestradiol, insulin and leptin stimulate rapid, non-genomic G protein-coupled phosphorylation cascades, to increase fat deposition and create the vasoconstrictive, dyslipidemic features of metabolic syndrome; how aberrant GPER signalling induces benign prostatic hypertrophy; and how increased intracellular oestradiol stimulates mitogenic change and tumour-cell activators, to cause prostate cancer. In essence, the up-regulation of aromatase produces increased intracellular oestradiol, increases ER

  19. Formestane, a steroidal aromatase inhibitor after failure of non-steroidal aromatase inhibitors (anastrozole and letrozole): is a clinical benefit still achievable?

    PubMed

    Carlini, P; Frassoldati, A; De Marco, S; Casali, A; Ruggeri, E M; Nardi, M; Papaldo, P; Fabi, A; Paoloni, F; Cognetti, F

    2001-11-01

    There are few clinical data on the sequential use of aromatase inhibitors (AI). This paper focuses on the relevance of clinical benefit CB (CR + PR + SD > or = 6 months) in postmenopausal metastatic breast cancer (MBC) patients treated with the steroidal aromatase inhibitor (SAI) formestane (FOR). who had already received non-steroidal aromatase inhibitor (nSAI): letrozole (LTZ) or anastrozole (ANZ). Twenty postmenopausal women with MBC were analysed in this retrospective two-centre study with the sequence nSAI-FOR. When receiving ANZ, 1 of 11 achieved a complete response and 9 of 11 a stable disease > or = 6 months, and receiving LTZ 1 of 9 achieved a partial response and 4 of 9 a stable disease > or = 6 months. The analysis of the entire population treated with FOR showed an overall CB of 55% (11 of 20) with a median duration of 15 months and median time to progression (TTP) of 6 months. Formestane 250 mg once bi-weekly seems to be an attractive alternative third-line hormonal therapy for the treatment of patients with MBC, previously treated with nSAI.

  20. Characterization of Aromatase Expression in the Adult Male and Female Mouse Brain. I. Coexistence with Oestrogen Receptors α and β, and Androgen Receptors

    PubMed Central

    Stanić, Davor; Dubois, Sydney; Chua, Hui Kheng; Tonge, Bruce; Rinehart, Nicole; Horne, Malcolm K.; Boon, Wah Chin

    2014-01-01

    Aromatase catalyses the last step of oestrogen synthesis. There is growing evidence that local oestrogens influence many brain regions to modulate brain development and behaviour. We examined, by immunohistochemistry, the expression of aromatase in the adult male and female mouse brain, using mice in which enhanced green fluorescent protein (EGFP) is transcribed following the physiological activation of the Cyp19A1 gene. EGFP-immunoreactive processes were distributed in many brain regions, including the bed nucleus of the stria terminalis, olfactory tubercle, medial amygdaloid nucleus and medial preoptic area, with the densest distributions of EGFP-positive cell bodies in the bed nucleus and medial amygdala. Differences between male and female mice were apparent, with the density of EGFP-positive cell bodies and fibres being lower in some brain regions of female mice, including the bed nucleus and medial amygdala. EGFP-positive cell bodies in the bed nucleus, lateral septum, medial amygdala and hypothalamus co-expressed oestrogen receptor (ER) α and β, or the androgen receptor (AR), although single-labelled EGFP-positive cells were also identified. Additionally, single-labelled ERα−, ERβ- or AR-positive cell bodies often appeared to be surrounded by EGFP-immunoreactive nerve fibres/terminals. The widespread distribution of EGFP-positive cell bodies and fibres suggests that aromatase signalling is common in the mouse brain, and that locally synthesised brain oestrogens could mediate biological effects by activating pre- and post-synaptic oestrogen α and β receptors, and androgen receptors. The higher number of EGFP-positive cells in male mice may indicate that the autocrine and paracrine effects of oestrogens are more prominent in males than females. PMID:24646567

  1. Direct Effects, Compensation, and Recovery in Female Fathead Minnows Exposed to a Model Aromatase Inhibitor

    EPA Science Inventory

    The paper reports on the effects of a model aromatase inhibitor, fadrozole, on molecular and biochemical endpoints within the fathead minnow reproductive axis. Unlike previous studies, this work incorporated extensive time-course characterization over the course of an 8 d exposu...

  2. Dienogest reduces proliferation, aromatase expression and angiogenesis, and increases apoptosis in human endometriosis.

    PubMed

    Miyashita, Mariko; Koga, Kaori; Takamura, Masashi; Izumi, Gentaro; Nagai, Miwako; Harada, Miyuki; Hirata, Tetsuya; Hirota, Yasushi; Fujii, Tomoyuki; Osuga, Yutaka

    2014-09-01

    Dienogest is a novel progestin that is highly selective for progesterone receptors and inhibits endometriosis. However, it remains unknown how the administration of dienogest to patients with endometriosis impacts on their lesion tissues. The aim of this study was to evaluate the in vivo effect of dienogest on endometriosis tissue. We collected endometrioma tissues from patients treated with dienogest (N = 7) or not treated (N = 11, controls). Cell proliferation, aromatase expression and blood vessel density were evaluated by staining for Ki67, aromatase and the von Willebrand factor, respectively. Apoptosis was detected using the TUNEL assay. The proportion of Ki67 and aromatase positive epithelial cells was significantly lower in the dienogest group than in controls (p < 0.05, respectively). The number of TUNEL positive cells was significantly higher in the dienogest group (p < 0.05). The density of blood vessels in endometrioma was marginally lower in the dienogest group compared with controls (p = 0.20). Our study demonstrates that endometrioma taken from patients treated with dienogest show remarkable histological features such as reduction of proliferation, aromatase expression and angiogenesis, and increase of apoptosis. This study clarified the impact of dienogest on local histological events that explain its therapeutic effect on endometriosis.

  3. A Study to Evaluate Genetic Predictors of Aromatase Inhibitor Musculoskeletal Symptoms (AIMSS) | Division of Cancer Prevention

    Cancer.gov

    E1Z11 is a study to determine whether certain genetic information can predict which breast cancer patients will discontinue treatment with AIs due to the development of musculoskeletal symptoms (MSS). Women with stage 1-111 breast cancer who are prescribed the aromatase inhibitor anastrozole as treatment may join. |

  4. Hypothesis testing with computational modeling: linking aromatase inhibition with plasma vitellogenin dynamics in fathead minnows

    EPA Science Inventory

    Fadrozole inhibits aromatase (CYP19A), a key enzyme that converts testosterone to estradiol (E2). In fish, E2 concentrations control hepatic synthesis ofthe glycolipoprotein vitellogenin (VTG), an egg yolk precursor protein essential to oocyte development and larval survival. Whe...

  5. Direct Effects, Compensation, and Recovery in Female Fathead Minnows Exposed to the Aromatase Inhibitor Fadrozole

    EPA Science Inventory

    A variety of chemicals present in the environment have the potential to inhibit aromatase, an enzyme critical to estrogen synthesis. The objective of this study was to provide a detailed characterization of the molecular and biochemical responses of female fathead minnows to a m...

  6. High-Throughput Analysis of Ovarian Cycle Disruption by Mixtures of Aromatase Inhibitors

    PubMed Central

    Golbamaki-Bakhtyari, Nazanin; Kovarich, Simona; Tebby, Cleo; Gabb, Henry A.; Lemazurier, Emmanuel

    2017-01-01

    Background: Combining computational toxicology with ExpoCast exposure estimates and ToxCast™ assay data gives us access to predictions of human health risks stemming from exposures to chemical mixtures. Objectives: We explored, through mathematical modeling and simulations, the size of potential effects of random mixtures of aromatase inhibitors on the dynamics of women's menstrual cycles. Methods: We simulated random exposures to millions of potential mixtures of 86 aromatase inhibitors. A pharmacokinetic model of intake and disposition of the chemicals predicted their internal concentration as a function of time (up to 2 y). A ToxCast™ aromatase assay provided concentration–inhibition relationships for each chemical. The resulting total aromatase inhibition was input to a mathematical model of the hormonal hypothalamus–pituitary–ovarian control of ovulation in women. Results: Above 10% inhibition of estradiol synthesis by aromatase inhibitors, noticeable (eventually reversible) effects on ovulation were predicted. Exposures to individual chemicals never led to such effects. In our best estimate, ∼10% of the combined exposures simulated had mild to catastrophic impacts on ovulation. A lower bound on that figure, obtained using an optimistic exposure scenario, was 0.3%. Conclusions: These results demonstrate the possibility to predict large-scale mixture effects for endocrine disrupters with a predictive toxicology approach that is suitable for high-throughput ranking and risk assessment. The size of the effects predicted is consistent with an increased risk of infertility in women from everyday exposures to our chemical environment. https://doi.org/10.1289/EHP742 PMID:28886606

  7. [Effects of aromatase inhibitor on sexual differentiation of SDN-POA in rats].

    PubMed

    Ohe, E

    1994-03-01

    The sexually dimorphic nucleus of the preoptic area (SDN-POA) of male rats is larger than that of females, the difference being caused by the perinatal effect of estrogen converted from androgen. To investigate the role of estrogen formation in the SDN-POA during the critical period of this sexual differentiation, CGS16949A (0.5 mg/kg, sc) was injected into the mothers in the late gestational age(F) or into neonates for 14 days from birth(N). Animals were sacrificed on the 20th. day of gestation and 7 days after birth, and fetal and neonatal brain aromatase activities (AA) as well as serum levels of testosterone(T) and corticosterone(B) were measured. On the 30th day after birth, the offspring of treated mothers and neonatally treated rats were sacrificed and the cross-sectional areas of the SDN-POA were evaluated by image processor NEXUS 6800. In group F, CGS16949A markedly suppressed brain AA in vitro (fetal hypothalamus: IC50 1.4nM) and in vivo in both the hypothalamus and amygdala. However, the levels of T and B did not show any significant change in group F. The same depression of AA was also observed in group N on the 7th day after birth. In CGS-treated males in groups F and N, the SDN-POA area markedly decreased to that of control females. The area in males in group F was not significantly different from that in females. These results suggest that estrogen converted from androgen plays a dominant role in the development of sexual dimorphism of the SDN-POA, and that the brain AA in the pre- and postnatal period is important in this process.

  8. Association of aromatase (TTTA)n repeat polymorphisms with central precocious puberty in girls.

    PubMed

    Lee, Hae Sang; Kim, Kyung Hee; Hwang, Jin Soon

    2014-09-01

    Precocious puberty is characterized by early activation of the pituitary-gonadal axis. Oestrogen is the final key factor to start the onset of puberty. The cytochrome P450 19A1 (CYP19A1) gene encodes an aromatase that is responsible for the conversion of androgens to oestrogen, which is a key step in oestrogen biosynthesis. The aim of this study was to identify CYP19A1 gene mutations or polymorphisms in girls with central precocious puberty (CPP). We evaluated the frequency of allelic variants of the CYP19A1 exons and the tetranucleotide tandem repeat (TTTA)n in intron 4 in 203 idiopathic central precocious puberty (CPP) girls and 101 normal healthy women. The genotype analysis of the CYP19A1 (TTTA)n polymorphism revealed six different alleles ranging from seven to 13 repeats. Among the six different repeat alleles detected in this study, the (TTTA)₁₃ repeat allele was only detected in the patient group and carriers of the (TTTA)₁₃ allele were significantly associated with an increased risk of CPP (OR = 1·509, 95% CI = 1·425-1·598, P = 0·033). Carriers of the (TTTA)₁₃ repeat allele were significantly younger at pubertal onset and had higher levels of oestrogen than noncarriers of the (TTTA)₁₃ repeat allele. Although nine polymorphisms were detected in exons of the CYP19A1 gene, no clinical significance was observed. In this study, carriers of a higher repeat (TTTA)₁₃ polymorphism in intron 4 of the CYP19A1 gene had higher levels of oestrogen. Those carrying the (TTTA)₁₃ repeat allele may have a higher risk of developing CPP. © 2014 John Wiley & Sons Ltd.

  9. Acupuncture does not ameliorate metabolic disturbances in the P450 aromatase inhibitor-induced rat model of polycystic ovary syndrome.

    PubMed

    Maliqueo, Manuel; Benrick, Anna; Marcondes, Rodrigo Rodrigues; Johansson, Julia; Sun, Miao; Stener-Victorin, Elisabet

    2017-01-01

    What is the central question of this study? The effectiveness of low-frequency electroacupuncture in the treatment of metabolic disorders associated with polycystic ovary syndrome (PCOS), an endocrine-metabolic disorder characterized by an imbalance in sex steroid production, is controversial. What is the main finding and its importance? In a rat model of PCOS induced by the inhibition of P450 aromatase, low-frequency electroacupuncture increased low-density lipoprotein-cholesterol but did not improve the insulin resistance or the adipose tissue dysfunction, suggesting that a balance of sex steroids is needed to restore the metabolic function in this rat model of PCOS. Low-frequency electroacupuncture restores sex steroid synthesis and sympathetic activity in women with polycystic ovary syndrome, which may ameliorate its metabolic disturbances, probably by modulating sympathetic nerve activity or sex steroid synthesis. We investigated whether low-frequency electroacupuncture regulates the metabolic function to the same extent as treatment with estradiol or β-adrenergic blocking in a rat model of polycystic ovary syndrome induced by a P450 aromatase inhibitor (letrozole). Letrozole (200 μg day -1 ) or placebo pellets were implanted in prepubertal Wistar rats. Six weeks thereafter, rats were treated for 5-6 weeks with the following: low-frequency electroacupuncture (5 days per week); a β-adrenergic blocker (propranolol hydrochloride, 0.1 mg kg -1 , 5 days per week); or 17β-estradiol (2.0 μg) every fourth day. Body weight development, body composition, locomotor activity, insulin sensitivity, tissue-specific glucose uptake, lipid profile, adipocyte size, serum concentrations of adiponectin and insulin, and gene expression in inguinal fat were measured. All treatments increased circulating levels of low-density lipoprotein-cholesterol. Estradiol treatment restored locomotor activity and increased insulin sensitivity but did not modify the glucose uptake in

  10. Early life exposure to environmental levels of the aromatase inhibitor tributyltin causes masculinisation and irreversible sperm damage in zebrafish (Danio rerio).

    PubMed

    McAllister, Brian G; Kime, David E

    2003-11-19

    To determine whether early life exposure to tributyltin (TBT), an aromatase inhibitor, impaired reproductive function in fish, Danio rerio were exposed to environmentally realistic levels (0.01-100 ng l(-1)) of TBT from 0 to 30, 30 to 60, and 0 to 70 days post-hatch, and the sex ratio and sperm motility of the adults examined 3-5 months after cessation of exposure. Fish exposed for 70 days to 0.1 ng l(-1) of TBT, a concentration presently below the detection limit in water, showed a male biased population which produced a high incidence of sperm lacking flagella. At 1 ng l(-1), the motility of sperm was significantly lower than that of control fish, while at 10 ng l(-1), all sperm lacked flagella and, at 100 ng l(-1), milt volume had increased. The effect of exposure on sex ratio was similar after exposure from 0 to 70 and 0 to 30 days, but even 100 ng l(-1) gave only 65% males after exposure from 30 to 60 days. Effects on sperm motility and morphology and on milt volume were less pronounced after 30 day than 70 day exposure. Our data suggest that screening for aromatase inhibiting activity and assessment of its risks in early life to human and wildlife fertility needs to be urgently addressed, and that the reproductive toxicity of TBT may presently be underestimated.

  11. Effects of Neonicotinoid Pesticides on Promoter-Specific Aromatase (CYP19) Expression in Hs578t Breast Cancer Cells and the Role of the VEGF Pathway.

    PubMed

    Caron-Beaudoin, Élyse; Viau, Rachel; Sanderson, J Thomas

    2018-04-26

    Aromatase (CYP19) is a key enzyme in estrogens biosynthesis. In the mammary gland, CYP19 gene is expressed at low levels under the regulation of its I.4 promoter. In hormone-dependent breast cancer, fibroblast cells surrounding the tumor express increased levels of CYP19 mRNA due to a decrease of I.4 promoter activity and an increase of PII, I.3, and I.7 promoter activity. Little is known about the effects of environmental chemicals on the promoter-specific CYP19 expression. We aimed to determine the effects of two neonicotinoids (thiacloprid and imidacloprid) on promoter-specific CYP19 expression in Hs578t breast cancer cells and understand the signaling pathways involved. Hs578t cells were exposed to various signaling pathway stimulants or neonicotinoids for 24 h. Promoter-specific expression of CYP19 was determined by real-time quantitative polymerase chain reaction and catalytic activity of aromatase by tritiated water release assay. To our knowledge, we are the first to demonstrate that the normal I.4 promoter and the breast cancer-relevant PII, I.3, and I.7 promoters of CYP19 are active in these cells. We found that the expression of CYP19 via promoters PII, I.3, and I.7 in Hs578t cells was, in part, dependent on the activation of two VEGF signaling pathways: mitogen-activated protein kinase (MAPK) 1/3 and phospholipase C (PLC). Exposure of Hs578t cells to environmental concentrations of imidacloprid and thiacloprid resulted in a switch in CYP19 promoter usage, involving inhibition of I.4 promoter activity and an increase of PII, I.3, and I.7 promoter-mediated CYP19 expression and aromatase catalytic activity. Greater effects were seen at lower concentrations. Our results suggest that thiacloprid and imidacloprid exert their effects at least partially by inducing the MAPK 1/3 and/or PLC pathways. We demonstrated in vitro that neonicotinoids may stimulate a change in CYP19 promoter usage similar to that observed in patients with hormone-dependent breast cancer

  12. Effect of aromatase inhibitor letrozole on the proliferation of spermatogonia by regulating the MAPK pathway.

    PubMed

    Wang, Shunde; Wang, Shuhong; Li, Hang; Li, Xiaoxia; Xie, Menglin; Wen, Jiayu; Li, Meicai; Long, Tengbo

    2018-06-01

    The molecular mechanism of the aromatase inhibitor letrozole was investigated. It promotes the proliferation of spermatogonia by regulating the mitogen-activated protein kinase (MAPK) pathway. Six different concentrations were selected for letrozole in order to incubate mouse spermatogonia [GC-1 spermatogonia (spg)] for 24, 48 and 72 h, respectively. Cell Counting Kit-8 (CCK-8) was used to observe the effect of letrozole on the proliferation of GC-1 spg cells, and the effect was further verified by cell plate clone formation assay. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis were used to detect the effects of letrozole on MAPK signaling pathways [Ras/extracellular signal-regulated kinase 1 (ERK1)/c-Myc], proliferation indexes [Ki-67 and proliferating cell nuclear antigen (PCNA)]. Bromodeoxyuridine (BrdU) staining was used to study the effects of letrozole and MAPK signaling pathways on cell proliferation. The results of CCK-8 showed that the proliferation rate of GC-1 spg cells was improved. Study results also revealed a significant increase in letrozole concentration along with the time of action. The results of plate clone formation assay further indicated that letrozole could significantly promote the proliferation capacity of GC-1 spg cells (p<0.05). The results of RT-PCR and western blot analysis confirmed letrozole significantly activated the expression of Ras/ERK1/c-Myc in the classical MAPK pathway. A significant increase was noted in the protein levels of Ki-67 and PCNA (p<0.05). By contrast, inhibition of the MAPK pathway resulted in a significant decrease in the levels of the above indexes (p<0.05). The number of BrdU cells in the letrozole group was also higher than that of the control group, while the number of BrdU-stained cells in the letrozole + MAPK inhibition group showed a significant decrease in comparison to the letrozole group. In conclusion, letrozole activated the MAPK signaling pathway and promoted the

  13. Diminished androgen and estrogen receptors and aromatase levels in hypogonadal diabetic men: reversal with testosterone.

    PubMed

    Ghanim, Husam; Dhindsa, Sandeep; Abuaysheh, Sanaa; Batra, Manav; Kuhadiya, Nitesh D; Makdissi, Antoine; Chaudhuri, Ajay; Dandona, Paresh

    2018-03-01

    One-third of males with type 2 diabetes (T2DM) have hypogonadism, characterized by low total and free testosterone concentrations. We hypothesized that this condition is associated with a compensatory increase in the expression of androgen receptors (AR) and that testosterone replacement reverses these changes. We also measured estrogen receptor and aromatase expression. This is a randomized double-blind placebo-controlled trial. Thirty-two hypogonadal and 32 eugonadal men with T2DM were recruited. Hypogonadal men were randomized to receive intramuscular testosterone or saline every 2 weeks for 22 weeks. We measured AR, ERα and aromatase expression in peripheral blood mononuclear cells (MNC), adipose tissue and skeletal muscle in hypogonadal and eugonadal males with T2DM at baseline and after 22 weeks of treatment in those with hypogonadism. The mRNA expression of AR, ERα (ESR1) and aromatase in adipose tissue from hypogonadal men was significantly lower as compared to eugonadal men, and it increased significantly to levels comparable to those in eugonadal patients with T2DM following testosterone treatment. AR mRNA expression was also significantly lower in MNC from hypogonadal patients compared to eugonadal T2DM patients. Testosterone administration in hypogonadal patients also restored AR mRNA and nuclear extract protein levels from MNC to that in eugonadal patients. In the skeletal muscle, AR mRNA and protein expression are lower in men with hypogonadism. Testosterone treatment restored AR expression levels to that comparable to levels in eugonadal men. We conclude that, contrary to our hypothesis, the expression of AR, ERα and aromatase is significantly diminished in hypogonadal men as compared to eugonadal men with type 2 diabetes. Following testosterone replacement, there is a reversal of these deficits. © 2018 European Society of Endocrinology.

  14. In situ aromatase expression in primary tumor is associated with estrogen receptor expression but is not predictive of response to endocrine therapy in advanced breast cancer

    PubMed Central

    2009-01-01

    Background New, third-generation aromatase inhibitors (AIs) have proven comparable or superior to the anti-estrogen tamoxifen for treatment of estrogen receptor (ER) and/or progesterone receptor (PR) positive breast cancer. AIs suppress total body and intratumoral estrogen levels. It is unclear whether in situ carcinoma cell aromatization is the primary source of estrogen production for tumor growth and whether the aromatase expression is predictive of response to endocrine therapy. Due to methodological difficulties in the determination of the aromatase protein, COX-2, an enzyme involved in the synthesis of aromatase, has been suggested as a surrogate marker for aromatase expression. Methods Primary tumor material was retrospectively collected from 88 patients who participated in a randomized clinical trial comparing the AI letrozole to the anti-estrogen tamoxifen for first-line treatment of advanced breast cancer. Semi-quantitative immunohistochemical (IHC) analysis was performed for ER, PR, COX-2 and aromatase using Tissue Microarrays (TMAs). Aromatase was also analyzed using whole sections (WS). Kappa analysis was applied to compare association of protein expression levels. Univariate Wilcoxon analysis and the Cox-analysis were performed to evaluate time to progression (TTP) in relation to marker expression. Results Aromatase expression was associated with ER, but not with PR or COX-2 expression in carcinoma cells. Measurements of aromatase in WS were not comparable to results from TMAs. Expression of COX-2 and aromatase did not predict response to endocrine therapy. Aromatase in combination with high PR expression may select letrozole treated patients with a longer TTP. Conclusion TMAs are not suitable for IHC analysis of in situ aromatase expression and we did not find COX-2 expression in carcinoma cells to be a surrogate marker for aromatase. In situ aromatase expression in tumor cells is associated with ER expression and may thus point towards good

  15. Potential use of COX-2–aromatase inhibitor combinations in breast cancer

    PubMed Central

    Bundred, N J; Barnes, N L P

    2005-01-01

    Cyclooxygenase-2 (COX-2) is overexpressed in several epithelial tumours, including breast cancer. Cyclooxygenase-2-positive tumours tend to be larger, higher grade, node-positive and HER-2/neu-positive. High COX-2 expression is associated with poor prognosis. Cyclooxygenase-2 inhibition reduces the incidence of tumours in animal models, inhibits the development of invasive cancer in colorectal cancer and reduces the frequency of polyps in familial adenomatous polyposis (FAP). These effects may be as a result of increased apoptosis, reduced angiogenesis and/or proliferation. Studies of COX-2 inhibitors in breast cancer are underway both alone and in combination with other agents. There is evidence to suggest that combining COX-2 inhibitors with aromatase inhibitors, growth factor receptor blockers, or chemo- or radiotherapy may be particularly effective. Preliminary results from combination therapy with celecoxib and exemestane in postmenopausal women with advanced breast cancer showed that the combination increased the time to recurrence. Up to 80% of ductal carcinomas in situ (DCISs) express COX-2, therefore COX-2 inhibition may be of particular use in this situation. Cyclooxygenase-2 expression correlates strongly with expression of HER-2/neu. As aromatase inhibitors appear particularly effective in patients with HER-2/neu-positive tumours, the combination of aromatase inhibitors and COX-2 inhibitors may be particularly useful in both DCIS and invasive cancer. PMID:16100520

  16. Benomyl induction of brain aromatase and toxic effects in the zebrafish embryo.

    PubMed

    Kim, Dong-Jae; Seok, Seung-Hyeok; Baek, Min-Won; Lee, Hui-Young; Na, Yi-Rang; Park, Sung-Hoon; Lee, Hyun-Kyoung; Dutta, Noton Kumar; Kawakami, Koichi; Park, Jae-Hak

    2009-05-01

    Benomyl is a benzimidazole fungicide that has been widely used on a variety of food crops and ornamental plants. It is known to cause adverse effects on reproductive systems, including decreased testicular and epididymal weights and reduced epididymal sperm counts and fertility. The brain aromatase gene is up-regulated by estrogens and estrogen mimics and considered a target gene to screen estrogen mimics. This study was designed to test the estrogenic potential and toxic effects of benomyl in the zebrafish system, and validated this system as a model that may correspond to the effect of benomyl in rodents. Concentrations of 20 x 10(-6), 40 x 10(-6) and 80 x 10(-6) M of benomyl-treated embryos showed decreased survival, hatching and heart rates, and increased incidence of malformations, such as pericardial edema, spinal lordosis, elongated heart, head edema, eye lens protrusion and caudal fin disappearance. Benomyl induced enhanced green fluorescent protein (EGFP) expression in the mediobasal hypothalamus (MBH) in transient zebrafish embryos with a brain aromatase-based reporter gene. In this study, we determined that benomyl has estrogenic potential based on zebrafish brain aromatase gene induction, and that benomyl is toxic at 20 x 10(-6) M concentration and higher. These results demonstrate the usefulness of zebrafish embryos as an in vivo system to examine the estrogenic and developmental toxic potential of unknown compounds.

  17. Magnolol protects osteoblastic MC3T3-E1 cells against antimycin A-induced cytotoxicity through activation of mitochondrial function.

    PubMed

    Choi, Eun Mi

    2012-06-01

    Antimycin A treatment of cells blocks the mitochondrial electron transport chain and leads to elevated ROS generation. In the present study, we investigated the protective effects of magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, on antimycin A-induced toxicity in osteoblastic MC3T3-E1 cells. Osteoblastic MC3T3-E1 cells were pre-incubated with magnolol before treatment with antimycin A. Cell viability and mineralization of osteoblasts were assessed by MTT assay and Alizarin Red staining, respectively. Mitochondrial dysfunction in cells was measured by mitochondrial membrane potential (MMP), complex IV activity, and ATP level. The cellular antioxidant effect of magnolol in osteoblastic MC3T3-E1 cells was assessed by measuring cardiolipin oxidation, mitochondrial superoxide levels, and nitrotyrosine content. Phosphorylated cAMP-response element-binding protein (CREB ) was evaluated using ELISA assay. Pretreatment with magnolol prior to antimycin A exposure significantly reduced antimycin A-induced osteoblast dysfunction by preventing MMP dissipation, ATP loss, and CREB inactivation. Magnolol also reduced cardiolipin peroxidation, mitochondrial superoxide, and nitrotyrosine production induced by antimycin A. These results suggest that magnolol has a protective effect against antimycin A-induced cell damage by its antioxidant effects and the attenuation of mitochondrial dysfunction. All these data indicate that magnolol may reduce or prevent osteoblast degeneration in osteoporosis or other degenerative disorders.

  18. Effect of Vibrio cholerae neuraminidase on the mitogen response of T lymphocytes. I. Enhancement of macrophage T-lymphocyte cooperation in concanavalin-A-induced lymphocyte activation.

    PubMed

    Knop, J

    1980-12-01

    Vibrio cholerae neuraminidase (VCN) enhances the immune response of lymphocytes in various systems, such as antigen- and mitogen-induced blastogenesis, mixed lymphocyte culture (MLC) and tumor-cell response. We used macrophage-depleted and reconstituted murine lymph-node T-cells to investigate the effect of VCN on macrophage-T-lymphocyte co-operation in Con-A-induced lymphocyte activation. In unfractionated lymph-node cells VCN enhanced the Con-A-induced lymphocyte activation as measured by 3H-thymidine (3H-dThd) incorporation. Removing macrophages from the cells resulted in a significantly diminished response. In addition the enhancing effect of VCN was greatly reduced. Reconstitution of the lymphocyte cultures with macrophages in increasing numbers and from various sources rstored the lymphocyte response and the enhancing effect of VCN. VCN proved to be most efficient in cultures reconstituted with normal peritoneal macrophages. Some effect was also observed using bone-marrow-derived (BM) macrophages. However, higher numbers of normal PE macrophages in the presence of VCN inhibited lymphocyte activation, and inhibition by thioglycollate-broth-induced macrophages was considerably increased by VCN. These results suggest that VCN acts by increasing the efficiency of macrophage-T lymphocyte interaction.

  19. Overexpression of Human-Derived DNMT3A Induced Intergenerational Inheritance of Active DNA Methylation Changes in Rat Sperm

    PubMed Central

    Zheng, Xiaoguo; Li, Zhenhua; Wang, Guishuan; Li, Zhengzheng; Liang, Ajuan; Wang, Hanshu; Dai, Yubing; Huang, Xingxu; Chen, Xuejin; Ma, Yuanwu; Sun, Fei

    2017-01-01

    DNA methylation is the major focus of studies on paternal epigenetic inheritance in mammals, but most previous studies about inheritable DNA methylation changes are passively induced by environmental factors. However, it is unclear whether the active changes mediated by variations in DNA methyltransferase activity are heritable. Here, we established human-derived DNMT3A (hDNMT3A) transgenic rats to study the effect of hDNMT3A overexpression on the DNA methylation pattern of rat sperm and to investigate whether this actively altered DNA methylation status is inheritable. Our results revealed that hDNMT3A was overexpressed in the testis of transgenic rats and induced genome-wide alterations in the DNA methylation pattern of rat sperm. Among 5438 reliable loci identified with 64 primer-pair combinations using a methylation-sensitive amplification polymorphism method, 28.01% showed altered amplified band types. Among these amplicons altered loci, 68.42% showed an altered DNA methylation status in the offspring of transgenic rats compared with wild-type rats. Further analysis based on loci which had identical DNA methylation status in all three biological replicates revealed that overexpression of hDNMT3A in paternal testis induced hypermethylation in sperm of both genotype-negative and genotype-positive offspring. Among the differentially methylated loci, 34.26% occurred in both positive and negative offspring of transgenic rats, indicating intergenerational inheritance of active DNA methylation changes in the absence of hDNM3A transmission. Furthermore, 75.07% of the inheritable loci were hyper-methylated while the remaining were hypomethylated. Distribution analysis revealed that the DNA methylation variations mainly occurred in introns and intergenic regions. Functional analysis revealed that genes related to differentially methylated loci were involved in a wide range of functions. Finally, this study demonstrated that active DNA methylation changes induced by h

  20. A Pilot Study Comparing the Effect of Flaxseed, Aromatase Inhibitor, and the Combination on Breast Tumor Biomarkers

    PubMed Central

    McCann, Susan E.; Edge, Stephen B.; Hicks, David G.; Thompson, Lilian U.; Morrison, Carl D.; Fetterly, Gerald; Andrews, Christopher; Clark, Kim; Wilton, John; Kulkarni, Swati

    2014-01-01

    Use of complementary approaches is common among breast cancer survivors. Potential interactions between aromatase inhibitors (AI) and high phytoestrogen foods, such as flaxseed (FS) are not often described. We conducted a pilot 2×2 factorial, randomized intervention study between tumor biopsy and resection, in 24 postmenopausal women with estrogen receptor positive (ER+) breast cancer, to assess the effects of flaxseed and anastrozole, and possible interactions between them, on serum steroid hormone and tumor-related characteristics associated with long-term survival (Roswell Park Cancer Institute, 2007–2010). The effect of each treatment vs placebo on outcomes was determined by linear regression adjusting for pre-treatment measure, stage, and grade. Although not statistically significant, mean ERβ expression was approximately 40% lower from pre- to post-intervention in the FS+AI group only. We observed a statistically significant negative association (β±SE −0.3±0.1; p=0.03) for androstenedione in the FS+AI group vs placebo and for DHEA with AI treatment (β±SE −1.6±0.6; p=0.009). Enterolactone excretion was much lower in the FS+AI group compared to the FS group. Our results do not support strong effects of flaxseed on AI activity for selected breast tumor characteristics or serum steroid hormone levels, but suggest AI therapy might reduce the production of circulating mammalian lignans from flaxseed. PMID:24669750

  1. Adaptation of an Evidence-Based Arthritis Program for Breast Cancer Survivors on Aromatase Inhibitor Therapy Who Experience Joint Pain

    PubMed Central

    Callahan, Leigh F.; Rini, Christine; Altpeter, Mary; Hackney, Betsy; Schecher, Arielle; Wilson, Anne; Muss, Hyman B.

    2015-01-01

    Adding aromatase inhibitors (AIs) to adjuvant treatment of postmenopausal women with hormone-receptor–positive breast cancer significantly reduces cancer recurrence. A common side effect of AIs is noninflammatory joint pain and stiffness (arthralgia) similar to arthritis symptoms. An evidence-based walking program developed by the Arthritis Foundation — Walk With Ease (WWE) — reduces arthritis-related joint symptoms. We hypothesized that WWE may also reduce AI-associated arthralgia. However, the potential for different barriers and facilitators to physical activity for these 2 patient populations suggested a need to adapt WWE before testing it with breast cancer survivors. We conducted qualitative research with 46 breast cancer survivors to explore program modification and inform the development of materials for an adapted program (Walk With Ease-Breast Cancer). Our process parallels the National Cancer Institute’s Research-Tested Intervention Programs (RTIPs) guidelines for adapting evidence-based programs for cancer populations. Findings resulted in a customized 8-page brochure to supplement existing WWE materials. PMID:26068412

  2. Opposite-directional sex change in functional female protandrous anemonefish, Amphiprion clarkii: effect of aromatase inhibitor on the ovarian tissue.

    PubMed

    Nakamura, Masaru; Miura, Saori; Nozu, Ryo; Kobayashi, Yasuhisa

    2015-01-01

    The anemonefish, Amphiprion clarkii, is a protandrous hermaphrodite. Under appropriate social conditions, male fish can become female. Previous studies indicated that estrogens are important regulators of sex change in this fish. However, the mechanism of sexual plasticity in the gonad of this fish is still unknown. To elucidate the mechanisms underlying the sexual plasticity in the ovary of female anemonefish, an aromatase inhibitor (AI, 500 μg/g diet) was administered to the functional female fish for 80 days. The levels of estradiol-17β (E2) in the fish treated with AI were significantly lower than those in the control group. Three out of five fish had ambisexual gonads with active spermatogenic germ cells in the ovarian tissue. However, female fish in the AI-treated group prior to treatment and those in the control group displayed no testicular characteristics in their developed ovaries. This result strongly suggests that germ cells with bipotentiality or spermatogonial cells remain in the functional ovaries of anemonefish following sex change from functional males to functional females. There is a possibility that estrogen depletion due to AI treatment might have caused the opposite-directional sex change from functional female to male in the anemonefish. The anemonefish keeps their high sexual bipotential in the ovary after sex change.

  3. Rapid effects of the aromatase inhibitor fadrozole on steroid production and gene expression in the ovary of female fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Cytochrome P450 aromatase catalyzes conversion of C19 androgens to C18 estrogens and is critical for normal reproduction in female vertebrates. Fadrozole is a well-studied aromatase inhibitor that has been shown to suppress estrogen production in the ovaries of fish. However, l...

  4. Effects of a short-term exposure to the aromatase inhibitor fadrozole on steroid production and gene expression in the ovary of female fathead minnows (Pimephales promelas)

    EPA Science Inventory

    Cytochrome P450 aromatase is a steriodogenic enzyme that converts C19 androgens to C18 estrogens and is critical for normal reproduction in females. Fadrozole is a well-studied aromatase inhibitor that has been shown to suppress estrogen production in the ovaries of fish. Howev...

  5. Brain aromatase (Cyp19A2) and estrogen receptors, in larvae and adult pejerrey fish Odontesthes bonariensis: Neuroanatomical and functional relations

    USGS Publications Warehouse

    Strobl-Mazzulla, P. H.; Lethimonier, C.; Gueguen, M.M.; Karube, M.; Fernandino, J.I.; Yoshizaki, G.; Patino, R.; Strussmann, C.A.; Kah, O.; Somoza, G.M.

    2008-01-01

    Although estrogens exert many functions on vertebrate brains, there is little information on the relationship between brain aromatase and estrogen receptors. Here, we report the cloning and characterization of two estrogen receptors, ?? and ??, in pejerrey. Both receptors' mRNAs largely overlap and were predominantly expressed in the brain, pituitary, liver, and gonads. Also brain aromatase and estrogen receptors were up-regulated in the brain of estradiol-treated males. In situ hybridization was performed to study in more detail, the distribution of the two receptors in comparison with brain aromatase mRNA in the brain of adult pejerrey. The estrogen receptors' mRNAs exhibited distinct but partially overlapping patterns of expression in the preoptic area and the mediobasal hypothalamus, as well as in the pituitary gland. Moreover, the estrogen receptor ??, but not ??, were found to be expressed in cells lining the preoptic recess, similarly as observed for brain aromatase. Finally, it was shown that the onset expression of brain aromatase and both estrogen receptors in the head of larvae preceded the morphological differentiation of the gonads. Because pejerrey sex differentiation is strongly influenced by temperature, brain aromatase expression was measured during the temperature-sensitive window and was found to be significantly higher at male-promoting temperature. Taken together these results suggest close neuroanatomical and functional relationships between brain aromatase and estrogen receptors, probably involved in the sexual differentiation of the brain and raising interesting questions on the origin (central or peripheral) of the brain aromatase substrate. ?? 2008 Elsevier Inc.

  6. The mitosis-regulating and protein-protein interaction activities of astrin are controlled by aurora-A-induced phosphorylation.

    PubMed

    Chiu, Shao-Chih; Chen, Jo-Mei Maureen; Wei, Tong-You Wade; Cheng, Tai-Shan; Wang, Ya-Hui Candice; Ku, Chia-Feng; Lian, Chiao-Hsuan; Liu, Chun-Chih Jared; Kuo, Yi-Chun; Yu, Chang-Tze Ricky

    2014-09-01

    Cells display dramatic morphological changes in mitosis, where numerous factors form regulatory networks to orchestrate the complicated process, resulting in extreme fidelity of the segregation of duplicated chromosomes into two daughter cells. Astrin regulates several aspects of mitosis, such as maintaining the cohesion of sister chromatids by inactivating Separase and stabilizing spindle, aligning and segregating chromosomes, and silencing spindle assembly checkpoint by interacting with Src kinase-associated phosphoprotein (SKAP) and cytoplasmic linker-associated protein-1α (CLASP-1α). To understand how Astrin is regulated in mitosis, we report here that Astrin acts as a mitotic phosphoprotein, and Aurora-A phosphorylates Astrin at Ser(115). The phosphorylation-deficient mutant Astrin S115A abnormally activates spindle assembly checkpoint and delays mitosis progression, decreases spindle stability, and induces chromosome misalignment. Mechanistic analyses reveal that Astrin phosphorylation mimicking mutant S115D, instead of S115A, binds and induces ubiquitination and degradation of securin, which sequentially activates Separase, an enzyme required for the separation of sister chromatids. Moreover, S115A fails to bind mitosis regulators, including SKAP and CLASP-1α, which results in the mitotic defects observed in Astrin S115A-transfected cells. In conclusion, Aurora-A phosphorylates Astrin and guides the binding of Astrin to its cellular partners, which ensures proper progression of mitosis. Copyright © 2014 the American Physiological Society.

  7. Higher than expected estradiol levels in aromatase inhibitor-treated, postmenopausal breast cancer patients.

    PubMed

    Kunovac Kallak, T; Baumgart, J; Stavreus Evers, A; Sundström Poromaa, I; Moby, L; Kask, K; Norjavaara, E; Kushnir, M M; Bergquist, J; Nilsson, K

    2012-10-01

    Vaginal estradiol is considered contraindicated in aromatase inhibitor (AI)-treated patients because of the risk of elevated estrogen levels. This leaves limited treatment options for patients experiencing gynecological symptoms. However, in clinical practice, no precise estimation has been performed of circulating estrogens and aromatase index in postmenopausal breast cancer patients on long-lasting AI or tamoxifen treatment. Steroid hormones were measured using liquid chromatography tandem mass spectrometry (LC-MS/MS) and extraction radioimmunoassay (RIA). Postmenopausal AI-treated patients (n =33) were compared with tamoxifen-treated patients (n =34) and controls without vaginal treatment (n =56), with vaginal estradiol (n =25), or with estriol (n =11) treatment. By use of LC-MS/MS, median (range) estradiol plasma concentrations were 16.7 (2.4-162.6), 31.0 (13.4-77.1), 27.2 (7.8-115.8) and 33.3 (20.3-340.1) pmol/l in AI-treated breast cancer patients, tamoxifen-treated breast cancer patients, postmenopausal controls and postmenopausal controls on vaginal estradiol, respectively. The AI-treated group and subgroups had significantly lower estradiol and estrone concentrations than all other groups (p <0.05). There was extensive interindividual variation in estradiol concentration within the AI-treated group, measured using both LC-MS/MS (2.3-182.0 pmol/l) and extraction RIA (2.4-162.6 pmol/l). The AI-treated group had lower aromatase index compared to all other groups (p <0.05-0.001). Circulating estrogen levels may have been underestimated in previous longitudinal studies of AI-treated breast cancer patients. Additional studies are required to further evaluate the role of circulating estrogens in breast cancer patients suffering from gynecological symptoms.

  8. Coadministrating luteolin minimizes the side effects of the aromatase inhibitor letrozole.

    PubMed

    Li, Fengjuan; Wong, Tsz Yan; Lin, Shu-mei; Chow, Simon; Cheung, Wing-hoi; Chan, Franky L; Chen, Shiuan; Leung, Lai K

    2014-11-01

    Aromatase inhibitors (AIs) have been used as adjuvant therapeutic agents for breast cancer. Their adverse side effect on blood lipid is well documented. Some natural compounds have been shown to be potential AIs. In the present study, we compared the efficacy of the flavonoid luteolin to the clinically approved AI letrozole (Femara; Novartis Pharmaceuticals, East Hanover, NJ) in a cell and a mouse model. In the in vitro experimental results for aromatase inhibition, the Ki values of luteolin and letrozole were estimated to be 2.44 µM and 0.41 nM, respectively. Both letrozole and luteolin appeared to be competitive inhibitors. Subsequently, an animal model was used for the comparison. Aromatase-expressing MCF-7 cells were transplanted into ovariectomized athymic mice. Luteolin was given by mouth at 5, 20, and 50 mg/kg, whereas letrozole was administered by intravenous injection. Similar to letrozole, luteolin administration reduced plasma estrogen concentrations and suppressed the xenograft proliferation. The regulation of cell cycle and apoptotic proteins-such as a decrease in the expression of Bcl-xL, cyclin-A/D1/E, CDK2/4, and increase in that of Bax-was about the same in both treatments. The most significant disparity was on blood lipids. In contrast to letrozole, luteolin increased fasting plasma high-density lipoprotein concentrations and produced a desirable blood lipid profile. These results suggested that the flavonoid could be a coadjuvant therapeutic agent without impairing the action of AIs. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

  9. The ovine sexually dimorphic nucleus, aromatase, and sexual partner preferences in sheep.

    PubMed

    Roselli, C E; Stormshak, F

    2010-02-28

    We are using the domestic ram as an experimental model to examine the role of aromatase in the development of sexual partner preferences. This interest has arisen because of the observation that as many as 8% of domestic rams are sexually attracted to other rams (male-oriented) in contrast to the majority of rams that are attracted to estrous ewes (female-oriented). Our findings demonstrate that aromatase expression is enriched in a cluster of neurons in the medial preoptic nucleus called the ovine sexually dimorphic nucleus (oSDN). The size of the oSDN is associated with a ram's sexual partner preference, such that the nucleus is 2-3 times larger in rams that are attracted to females (female-oriented) than in rams that are attracted to other rams (male-oriented). Moreover, the volume of the oSDN in male-oriented rams is similar to the volume in ewes. These volume differences are not influenced by adult concentrations of serum testosterone. Instead, we found that the oSDN is already present in late gestation lamb fetuses (approximately day 135 of gestation) when it is approximately 2-fold greater in males than in females. Exposure of genetic female fetuses to exogenous testosterone during the critical period for sexual differentiation masculinizes oSDN volume and aromatase expression when examined subsequently on day 135. The demonstration that the oSDN is organized prenatally by testosterone exposure suggests that the brain of the male-oriented ram may be under-androgenized during development. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Synthesis and evaluation of a dimer of 2-(4-pyridylmethyl)-1-indanone as a novel nonsteroidal aromatase inhibitor.

    PubMed

    Gupta, Ranju; Jindal, Dharam Paul; Jit, Birinder; Narang, Gaurav; Palusczak, Anja; Hartmann, Rolf W

    2004-07-01

    A novel dimer of 2-(4-pyridylmethyl)-1-indanone (2) was obtained while carrying out aldol condensation of 1-indanone with pyridine-4-carboxaldehyde in potassium hydroxide. The structure of dimer 3 has been established using various spectral techniques and was screened for its ability to inhibit the cytochrome P(450) enzyme aromatase. The dimer showed strong inhibition of human placental aromatase and was found 3 times more potent (RP = 3, IC(50) = 10.2 microM) as compared to aminoglutethimide (RP = 1, IC(50) = 18.5 microM.

  11. Brain aromatase and circulating corticosterone are rapidly regulated by combined acute stress and sexual interaction in a sex-specific manner.

    PubMed

    Dickens, M J; Balthazart, J; Cornil, C A

    2012-10-01

    Neural production of 17β-oestradiol via aromatisation of testosterone may play a critical role in rapid, nongenomic regulation of physiological and behavioural processes. In brain nuclei implicated in the control of sexual behaviour, sexual or stressfull stimuli induce, respectively, a rapid inhibition or increase in preoptic aromatase activity (AA). In the present study, we tested quail that were either nonstressed or acutely stressed (15 min of restraint) immediately before sexual interaction (5 min) with stressed or nonstressed partners. We measured nuclei-specific AA changes, corresponding behavioural output, fertilisation rates and corticosterone (CORT) concentrations. In males, sexual interaction rapidly reversed stress-induced increases of AA in the medial preoptic nucleus (POM). This time scale (< 5 min) highlights the dynamic potential of the aromatase system to integrate input from stimuli that drive AA in opposing directions. Moreover, acute stress had minimal effects on male behaviour, suggesting that the input from the sexual stimuli on POM AA may actively preserve sexual behaviour despite stress exposure. We also found distinct sex differences in contextual physiological responses: males did not show any effect of partner status, whereas females responded to both their stress exposure and the male partner's stress exposure at the level of circulating CORT and AA. In addition, fertilisation rates and female CORT correlated with the male partner's exhibition of sexually aggressive behaviour, suggesting that female perception of the male can affect their physiology as much as direct stress. Overall, male reproduction appears relatively simple: sexual stimuli, irrespective of stress, drives major neural changes including rapid reversal of stress-induced changes of AA. By contrast, female reproduction appears more nuanced and context specific, with subjects responding physiologically and behaviourally to stress, the male partner's stress exposure, and

  12. Sulfonanilide Derivatives in Identifying Novel Aromatase Inhibitors by Applying Docking, Virtual Screening, and MD Simulations Studies

    PubMed Central

    Son, Minky; Park, Chanin; Kim, Hyong-Ha; Suh, Jung-Keun

    2017-01-01

    Breast cancer is one of the leading causes of death noticed in women across the world. Of late the most successful treatments rendered are the use of aromatase inhibitors (AIs). In the current study, a two-way approach for the identification of novel leads has been adapted. 81 chemical compounds were assessed to understand their potentiality against aromatase along with the four known drugs. Docking was performed employing the CDOCKER protocol available on the Discovery Studio (DS v4.5). Exemestane has displayed a higher dock score among the known drug candidates and is labeled as reference. Out of 81 ligands 14 have exhibited higher dock scores than the reference. In the second approach, these 14 compounds were utilized for the generation of the pharmacophore. The validated four-featured pharmacophore was then allowed to screen Chembridge database and the potential Hits were obtained after subjecting them to Lipinski's rule of five and the ADMET properties. Subsequently, the acquired 3,050 Hits were escalated to molecular docking utilizing GOLD v5.0. Finally, the obtained Hits were consequently represented to be ideal lead candidates that were escalated to the MD simulations and binding free energy calculations. Additionally, the gene-disease association was performed to delineate the associated disease caused by CYP19A1. PMID:29312992

  13. Sulfonanilide Derivatives in Identifying Novel Aromatase Inhibitors by Applying Docking, Virtual Screening, and MD Simulations Studies.

    PubMed

    Rampogu, Shailima; Son, Minky; Park, Chanin; Kim, Hyong-Ha; Suh, Jung-Keun; Lee, Keun Woo

    2017-01-01

    Breast cancer is one of the leading causes of death noticed in women across the world. Of late the most successful treatments rendered are the use of aromatase inhibitors (AIs). In the current study, a two-way approach for the identification of novel leads has been adapted. 81 chemical compounds were assessed to understand their potentiality against aromatase along with the four known drugs. Docking was performed employing the CDOCKER protocol available on the Discovery Studio (DS v4.5). Exemestane has displayed a higher dock score among the known drug candidates and is labeled as reference. Out of 81 ligands 14 have exhibited higher dock scores than the reference. In the second approach, these 14 compounds were utilized for the generation of the pharmacophore. The validated four-featured pharmacophore was then allowed to screen Chembridge database and the potential Hits were obtained after subjecting them to Lipinski's rule of five and the ADMET properties. Subsequently, the acquired 3,050 Hits were escalated to molecular docking utilizing GOLD v5.0. Finally, the obtained Hits were consequently represented to be ideal lead candidates that were escalated to the MD simulations and binding free energy calculations. Additionally, the gene-disease association was performed to delineate the associated disease caused by CYP19A1.

  14. Aromatase Deficient Female Mice Demonstrate Altered Expression of Molecules Critical for Renal Calcium Reabsorption

    NASA Astrophysics Data System (ADS)

    Öz, Orhan K.; Hajibeigi, Asghar; Cummins, Carolyn; van Abel, Monique; Bindels, René J.; Kuro-o, Makoto; Pak, Charles Y. C.; Zerwekh, Joseph E.

    2007-04-01

    The incidence of kidney stones increases in women after the menopause, suggesting a role for estrogen deficiency. In order to determine if estrogen may be exerting an effect on renal calcium reabsorption, we measured urinary calcium excretion in the aromatase-deficient female mouse (ArKO) before and following estrogen therapy. ArKO mice had hypercalciuria that corrected during estrogen administration. To evaluate the mechanism by which estrogen deficiency leads to hypercalciuria, we examined the expression of several proteins involved in distal tubule renal calcium reabsorption, both at the message and protein levels. Messenger RNA levels of TRPV5, TRPV6, calbindin-D28K, the Na+/Ca++ exchanger (NCX1), and the plasma membrane calcium ATPase (PMCA1b) were significantly decreased in kidneys of ArKO mice. On the other hand, klotho mRNA levels were elevated in kidneys of ArKO mice. ArKO renal protein extracts had lower levels of calbindin-D28K but higher levels of the klotho protein. Immunochemistry demonstrated increased klotho expression in ArKO kidneys. Estradiol therapy normalized the expression of TRPV5, calbindin-D28K, PMCA1b and klotho. Taken together, these results demonstrate that estrogen deficiency produced by aromatase inactivation is sufficient to produce a renal leak of calcium and consequent hypercalciuria. This may represent one mechanism leading to the increased incidence of kidney stones following the menopause in women.

  15. The mRNA expression of P450 aromatase, gonadotropin beta-subunits and FTZ-F1 in the orange-spotted grouper (Epinephelus Coioides) during 17alpha-methyltestosterone-induced precocious sex change.

    PubMed

    Zhang, Weimin; Zhang, Yong; Zhang, Lihong; Zhao, Huihong; Li, Xin; Huang, He; Lin, Haoran

    2007-06-01

    The orange-spotted grouper Epinephelus coioides is a protogynous hermaphroditic fish, but the physiological basis of its sex change remains largely unknown. In the present study, the 2-year-old orange-spotted grouper was induced to change sex precociously by oral administration of 17alpha-methyltestosterone (MT, 50 mg/Kg diet, twice a day at daily ration of 5% bodyweight) for 60 days. The serum testosterone levels were significantly elevated after MT treatment for 20 and 40 days as compared to control, but the levels of serum estradiol (E(2)) remained unchanged. The expression of P450aromA in the gonad significantly decreased after MT treatment for 20, 40, and 60 days. Accordingly, the enzyme activity of gonadal aromatase was also lower. The expression of FSHbeta subunit in the pituitary was significantly decreased after MT treatment for 20 days, but returned to the control levels after 40 and 60 days; however, the expression of LHbeta subunit was not altered significantly by MT treatment. The expression of FTZ-F1 in the gonad also decreased significantly in response to MT treatment for 40 and 60 days, but its expression in the pituitary was not altered significantly. Interestingly, when tested in vitro on ovarian fragments, MT had no direct effect on the expression of P450aromA and FTZ-F1 as well as the activity of gonadal aromatase, suggesting that the inhibition of gonadal P450aromatase and FTZ-F1 by MT may be mediated at upper levels of the brain-pituitary-gonadal axis. Taken together, these results indicated that FSH, P450aromA, FTZ-F1, and serum testosterone are associated with the MT-induced sex change of the orange-spotted grouper, but the cause-effect relationship between these factors and sex change in this species remains to be characterized. (c) 2006 Wiley-Liss, Inc.

  16. Perinatal administration of aromatase inhibitors in rodents as animal models of human male homosexuality: similarities and differences.

    PubMed

    Olvera-Hernández, Sandra; Fernández-Guasti, Alonso

    2015-01-01

    In this chapter we briefly review the evidence supporting the existence of biological influences on sexual orientation. We focus on basic research studies that have affected the estrogen synthesis during the critical periods of brain sexual differentiation in male rat offspring with the use of aromatase inhibitors, such as 1,4,6-androstatriene-3,17 (ATD) and letrozole. The results after prenatal and/or postnatal treatment with ATD reveal that these animals, when adults, show female sexual responses, such as lordosis or proceptive behaviors, but retain their ability to display male sexual activity with a receptive female. Interestingly, the preference and sexual behavior of these rats vary depending upon the circadian rhythm.Recently, we have established that the treatment with low doses of letrozole during the second half of pregnancy produces male rat offspring, that when adults spend more time in the company of a sexually active male than with a receptive female in a preference test. In addition, they display female sexual behavior when forced to interact with a sexually experienced male and some typical male sexual behavior when faced with a sexually receptive female. Interestingly, these males displayed both sexual behavior patterns spontaneously, i.e., in absence of exogenous steroid hormone treatment. Most of these features correspond with those found in human male homosexuals; however, the "bisexual" behavior shown by the letrozole-treated rats may be related to a particular human population. All these data, taken together, permit to propose letrozole prenatal treatment as a suitable animal model to study human male homosexuality and reinforce the hypothesis that human sexual orientation is underlied by changes in the endocrine milieu during early development.

  17. Investigating the Regulation and Potential Role of Nonhypoxic Hypoxia Inducible Factor 1 (HIF 1) in Aromatase Inhibitor Resistant Breast Cancer

    DTIC Science & Technology

    2015-12-01

    resistance include: 1) cancer stem cell maintenance markers (Oct-4, kit ligand, JARID1B); 2) epithelial- mesenchymal -transition (EMT) markers (Snail...target proteins, such as BCRP andvimentin. BCRP and vimentin contribute to letrozole resistance through their effects on maintaining cacer stem cell ...treatment of acquired AI resistance. 15. SUBJECT TERMS Breast cancer, aromatase inhibitors (ex. letrozole), drug resistance, cancer stem cells ,nonhypoxic

  18. EVALUATION OF THE AROMATASE INHIBITOR FADROZOLE IN A SHORT-TERM REPRODUCTION ASSAY WITH THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

    EPA Science Inventory

    Cytochrome P450 aromatase is a key enzyme in vertebrate steroidogenesis, catalyzing the conversion of C19 androgens to C18 estrogens such a B-estradiol (E2). The objective of this study was to assess effects of the CYP inhibitor fadrozole on fathead minnow reproductive endocrinol...

  19. Defining the Biological Domain of Applicability of Adverse Outcome Pathways Across Diverse Species: The Estrogen Receptor/Aromatase Case Study

    EPA Science Inventory

    Aromatase inhibitors (e.g. fadrozole, prochloraz) and estrogen receptor antagonists (e.g. tamoxifen) reduce the circulating concentration of 17β-estradiol, leading to reproductive dysfunction in affected organisms. While these toxic effects are well-characterized in fish and...

  20. Quantitative (q)AOP for aromatase inhibition as case study to advance qAOP development practices

    EPA Science Inventory

    Here we describe how “read across” of a quantitative adverse outcome pathway (qAOP) developed with data for one chemical can be used to screen impacts of other chemicals. We developed a qAOP starting with inhibition of CYP19A (aromatase) in fathead minnows (FHM) as th...

  1. Computational modeling of dynamic alteration of plasma vitellogenin in response to aromatase CYP19 inhibition in fathead minnows

    EPA Science Inventory

    In vertebrates, conversion of testosterone into 17β-estradiol (E2) is catalyzed by cytochrome P450 (CYP) 19A aromatase. An important role of E2 in oviparous vertebrates such as fish is stimulation of hepatic synthesis of the glycolipoprotein vitellogenin (VTG), an egg yolk precur...

  2. Expression of aromatase in the embryonic brain of the olive ridley sea turtle (Lepidochelys olivacea), and the effect of bisphenol-A in sexually differentiated embryos.

    PubMed

    Gómez-Picos, Patsy; Sifuentes-Romero, Itzel; Merchant-Larios, Horacio; Hernández-Cornejo, Rubí; Díaz-Hernández, Verónica; García-Gasca, Alejandra

    2014-01-01

    Brain aromatase participates in several biological processes, such as regulation of the reproductive-endocrine axis, memory, stress, sexual differentiation of the nervous system, male sexual behavior, and brain repair. Here we report the isolation and expression of brain aromatase in olive ridley sea turtle (Lepidochelys olivacea) embryos incubated at male- and female-promoting temperatures (MPT and FPT, respectively), at the thermosensitive period (TSP) and the sex-differentiated period. Also, aromatase expression was assessed in differentiated embryos exposed to bisphenol-A (BPA) during the TSP. BPA is a monomer of polycarbonate plastics and is considered an endocrine-disrupting compound. Normal aromatase expression was measured in both forebrain and hindbrain, showing higher expression levels in the forebrain of differentiated embryos at both incubation temperatures. Although no significant differences were detected in the hindbrain, expression was slightly higher at MPT. BPA did not affect aromatase expression neither in forebrains or hindbrains from embryos incubated at MPT, whereas at FPT an inverted U-shape curve was observed in forebrains with significant differences at lower concentrations, whereas in hindbrains a non-significant increment was observed at higher concentrations. Our data indicate that both incubation temperature and developmental stage are critical factors affecting aromatase expression in the forebrain. Because of the timing and location of aromatase expression in the brain, we suggest that brain aromatase may participate in the imprinting of sexual trends related to reproduction and sexual behavior at the onset of sex differentiation, and BPA exposure may impair aromatase function in the female forebrain.

  3. Paternal Retrieval Behavior Regulated by Brain Estrogen Synthetase (Aromatase) in Mouse Sires that Engage in Communicative Interactions with Pairmates.

    PubMed

    Akther, Shirin; Huang, Zhiqi; Liang, Mingkun; Zhong, Jing; Fakhrul, Azam A K M; Yuhi, Teruko; Lopatina, Olga; Salmina, Alla B; Yokoyama, Shigeru; Higashida, Chiharu; Tsuji, Takahiro; Matsuo, Mie; Higashida, Haruhiro

    2015-01-01

    Parental behaviors involve complex social recognition and memory processes and interactive behavior with children that can greatly facilitate healthy human family life. Fathers play a substantial role in child care in a small but significant number of mammals, including humans. However, the brain mechanism that controls male parental behavior is much less understood than that controlling female parental behavior. Fathers of non-monogamous laboratory ICR mice are an interesting model for examining the factors that influence paternal responsiveness because sires can exhibit maternal-like parental care (retrieval of pups) when separated from their pups along with their pairmates because of olfactory and auditory signals from the dams. Here we tested whether paternal behavior is related to femininity by the aromatization of testosterone. For this purpose, we measured the immunoreactivity of aromatase [cytochrome P450 family 19 (CYP19)], which synthesizes estrogen from androgen, in nine brain regions of the sire. We observed higher levels of aromatase expression in these areas of the sire brain when they engaged in communicative interactions with dams in separate cages. Interestingly, the number of nuclei with aromatase immunoreactivity in sires left together with maternal mates in the home cage after pup-removing was significantly larger than that in sires housed with a whole family. The capacity of sires to retrieve pups was increased following a period of 5 days spent with the pups as a whole family after parturition, whereas the acquisition of this ability was suppressed in sires treated daily with an aromatase inhibitor. The results demonstrate that the dam significantly stimulates aromatase in the male brain and that the presence of the pups has an inhibitory effect on this increase. These results also suggest that brain aromatization regulates the initiation, development, and maintenance of paternal behavior in the ICR male mice.

  4. Review of hormone-based treatments in postmenopausal patients with advanced breast cancer focusing on aromatase inhibitors and fulvestrant

    PubMed Central

    Kümler, Iben; Knoop, Ann S; Jessing, Christina A R; Ejlertsen, Bent; Nielsen, Dorte L

    2016-01-01

    Background Endocrine therapy constitutes a central modality in the treatment of oestrogen receptor (ER)-positive advanced breast cancer. Purpose To evaluate the evidence for endocrine treatment in postmenopausal patients with advanced breast cancer focusing on the aromatase inhibitors, letrozole, anastrozole, exemestane and fulvestrant. Methods A review was carried out using PubMed. Randomised phase II and III trials reporting on ≥100 patients were included. Results 35 trials met the inclusion criteria. If not used in the adjuvant setting, a non-steroid aromatase inhibitor was the optimal first-line option. In general, the efficacy of the different aromatase inhibitors and fulvestrant was similar in tamoxifen-refractory patients. A randomised phase II trial of palbociclib plus letrozole versus letrozole alone showed significantly increased progression-free survival (PFS) when compared with endocrine therapy alone in the first-line setting (20.2 vs 10.2 months). Furthermore, the addition of everolimus to exemestane in the Breast Cancer Trials of OraL EveROlimus-2 (BOLERO-2) study resulted in an extension of median PFS by 4.5 months after recurrence/progression on a non-steroid aromatase inhibitor. However, overall survival was not significantly increased. Conclusion Conventional treatment with an aromatase inhibitor or fulvestrant may be an adequate treatment option for most patients with hormone receptor-positive advanced breast cancer. Mammalian target of rapamycin (mTOR) inhibition and cyclin-dependent kinase 4/6 (CDK4/6) inhibition might represent substantial advances for selected patients in some specific settings. However, there is an urgent need for prospective biomarker-driven trials to identify patients for whom these treatments are cost-effective. PMID:27843622

  5. MiR-20a Induces Cell Radioresistance by Activating the PTEN/PI3K/Akt Signaling Pathway in Hepatocellular Carcinoma

    SciTech Connect

    Zhang, Yuqin; Zheng, Lin; Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province

    2015-08-01

    Purpose: To investigate the role of miR-20a in hepatocellular carcinoma (HCC) cell radioresistance, which may reveal potential strategies to improve treatment. Methods and Materials: The expression of miR-20a and PTEN were detected in HCC cell lines and paired primary tissues by quantitative real-time polymerase chain reaction. Cell radiation combined with colony formation assays was administrated to discover the effect of miR-20a on radiosensitivity. Bioinformatics prediction and luciferase assay were used to identify the target of miR-20a. The phosphatidylinositol 3-kinase inhibitor LY294002 was used to inhibit phosphorylation of Akt, to verify whether miR-20a affects HCC cell radioresistance through activating the PTEN/PI3K/Aktmore » pathway. Results: MiR-20a levels were increased in HCC cell lines and tissues, whereas PTEN was inversely correlated with it. Overexpression of miR-20a in Bel-7402 and SMMC-7721 cells enhances their resistance to the effect of ionizing radiation, and the inhibition of miR-20a in HCCLM3 and QGY-7701 cells sensitizes them to it. PTEN was identified as a direct functional target of miR-20a for the induction of radioresistance. Overexpression of miR-20a activated the PTEN/PI3K/Akt signaling pathway. Additionally, the kinase inhibitor LY294002 could reverse the effect of miR-20a–induced radioresistance. Conclusion: MiR-20a induces HCC cell radioresistance by activating the PTEN/PI3K/Akt pathway, which suggests that miR-20a/PTEN/PI3K/Akt might represent a target of investigation for developing effective therapeutic strategies against HCC.« less

  6. Aromatase inhibition by letrozole attenuates kainic acid-induced seizures but not neurotoxicity in mice.

    PubMed

    Iqbal, Ramsha; Jain, Gaurav K; Siraj, Fouzia; Vohora, Divya

    2018-07-01

    Evidence shows neurosteroids play a key role in regulating epileptogenesis. Neurosteroids such as testosterone modulate seizure susceptibility through its transformation to metabolites which show proconvulsant and anticonvulsant effects, respectively. Reduction of testosterone by aromatase generates proconvulsant 17-β estradiol. Alternatively, testosterone is metabolized into 5α-dihydrotestosterone (5α-DHT) by 5α-reductase, which is then reduced by 3α-hydroxysteroid oxidoreductase enzyme (3α-HSOR) to form anticonvulsant metabolite 3α-androstanediol (3α-Diol), a potent GABA A receptor modulating neurosteroid. The present study evaluated whether inhibition of aromatase inhibitor letrozole protects against seizures and neuronal degeneration induced by kainic acid (KA) (10 mg/kg, i.p.) in Swiss albino mice. Letrozole (1 mg/kg, i.p.) administered one hour prior to KA significantly increased the onset time of seizures and reduced the% incidence of seizures. Pretreatment with finasteride, a selective inhibitor of 5α-reductase and indomethacin, a selective inhibitor of 3α-hydroxysteroid oxidoreductase enzyme (3α-HSOR), reversed the protective effects of letrozole in KA-induced seizures in mice. Microscopic examination using cresyl violet staining revealed that letrozole did not modify KA-induced neurotoxicity in the CA1, CA3 and DG region of the hippocampus. Letrozole treatment resulted in the reduced levels of 17-β estradiol and elevated the levels of 5α-dihydrotestosterone (DHT) and 3α-Diol in the hippocampus. Finasteride and indomethacin attenuated letrozole-induced elevations of 5α-DHT and 3α-Diol. Our results indicate the potential anticonvulsant effects of letrozole against KA-induced seizures in mice that might be mediated by inhibiting aromatization of testosterone to 17β-estradiol, a proconvulsant hormone and by redirecting the synthesis to anticonvulsant metabolites, 5α-DHT and 3α-Diol. Acute aromatase inhibition, thus, might be used as an

  7. Management of sexual dysfunction in postmenopausal breast cancer patients taking adjuvant aromatase inhibitor therapy

    PubMed Central

    Derzko, C.; Elliott, S.; Lam, W.

    2007-01-01

    Treatment with aromatase inhibitors for postmenopausal women with breast cancer has been shown to reduce or obviate invasive procedures such as hysteroscopy or curettage associated with tamoxifen-induced endometrial abnormalities. The side effect of upfront aromatase inhibitors, diminished estrogen synthesis, is similar to that seen with the natural events of aging. The consequences often include vasomotor symptoms (hot flushes) and vaginal dryness and atrophy, which in turn may result in cystitis and vaginitis. Not surprisingly, painful intercourse (dyspareunia) and loss of sexual interest (decreased libido) frequently occur as well. Various interventions, both non-hormonal and hormonal, are currently available to manage these problems. The purpose of the present review is to provide the practitioner with a wide array of management options to assist in treating the sexual consequences of aromatase inhibitors. The suggestions in this review are based on recent literature and on the recommendations set forth both by the North American Menopause Association and in the clinical practice guidelines of the Society of Gynaecologists and Obstetricians of Canada. The complexity of female sexual dysfunction necessitates a biopsychosocial approach to assessment and management alike, with interventions ranging from education and lifestyle changes to sexual counselling, pelvic floor therapies, sexual aids, medications, and dietary supplements—all of which have been reported to have a variable, but often successful, effect on symptom amelioration. Although the use of specific hormone replacement—most commonly local estrogen, and less commonly, systemic estrogen with or without an androgen, progesterone, or the additional of an androgen in an estrogenized woman (or a combination)—may be highly effective, the concern remains that in patients with estrogen-dependent breast cancer, including those receiving anti-estrogenic adjuvant therapies, the use of these hormones may be

  8. Induction of Female-to-Male Sex Change in Adult Zebrafish by Aromatase Inhibitor Treatment

    NASA Astrophysics Data System (ADS)

    Takatsu, Kanae; Miyaoku, Kaori; Roy, Shimi Rani; Murono, Yuki; Sago, Tomohiro; Itagaki, Hideyuki; Nakamura, Masaru; Tokumoto, Toshinobu

    2013-12-01

    This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect of aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction of the ovaries after which testes-like organs appeared, and cyst structures filled with spermatozoa-like cells were observed in sections of these tissues. Electron microscopic observations revealed that these cells appeared as large sperm heads without tails. Sperm formation was re-examined after changing the diet to an AI-free food. A large number of normal sperm were obtained after eight weeks, and no formation of ovarian tissue was observed. Artificial fertilization using sperm from the sex-changed females was successful. These results demonstrated that sex plasticity remains in the mature ovaries of this species.

  9. Prevention of aromatase inhibitor-induced bone loss with alendronate in postmenopausal women: The BATMAN Trial.

    PubMed

    Lomax, Anna J; Yee Yap, Saw; White, Karen; Beith, Jane; Abdi, Ehtesham; Broad, Adam; Sewak, Sanjeev; Lee, Chooi; Sambrook, Philip; Pocock, Nicholas; Henry, Margaret J; Yeow, Elaine G; Bell, Richard

    2013-12-01

    Postmenopausal women on aromatase inhibitors (AI) are at risk of aromatase inhibitor-associated bone loss (AIBL) and fractures. In 2005 Osteoporosis Australia proposed an algorithm for bisphosphonate intervention. Three hundred and three postmenopausal women with early breast cancer (EBC) were enrolled (osteoporotic, n=25; osteopaenic, n=146; normal bone mineral density (BMD), n=126). Weekly alendronate (70 mg) treatment efficacy as triggered by the algorithm in preventing bone loss was evaluated. All patients received anastrozole (1 mg daily), calcium and vitamin D. All osteoporotic patients received alendronate at baseline. Eleven out of the 146 (7.5%) osteopaenic patients commenced alendronate within 18 months of participation and eleven commenced after. One hundred and twenty four out of the 146 (84.9%) osteopaenic patients and all 126 with normal baseline BMD did not trigger the algorithm. At three years, lumbar spine mean BMD increased (15.6%, p<0.01) in the osteoporotic group. BMD in the osteopaenic group with early intervention significantly increased at three years (6.3%, p=0.02). No significant change was seen in the late intervention group. No change was observed in those with osteopaenia without alendronate. There was a significant drop in lumbar spine (-5.4%) and hip (-4.5%) mean BMD, in the normal BMD group, none of whom received alendronate. Fracture data will be presented. In postmenopausal women with endocrine-responsive EBC, BMD improved over time when a bisphosphonate is administered with anastrozole in osteoporotic patients using an osteoporosis schedule. Subjects with normal baseline BMD experienced the greatest BMD loss, although none became osteoporotic.

  10. Nandrolone and stanozolol upregulate aromatase expression and further increase IGF-I-dependent effects on MCF-7 breast cancer cell proliferation.

    PubMed

    Sirianni, Rosa; Capparelli, Claudia; Chimento, Adele; Panza, Salvatore; Catalano, Stefania; Lanzino, Marilena; Pezzi, Vincenzo; Andò, Sebastiano

    2012-11-05

    Several doping agents, such as anabolic androgenic steroids (AAS) and peptide hormones like insulin-like growth factor-I (IGF-I), are employed without considering the potential deleterious effects that they can cause. In addition, androgens are used in postmenopausal women as replacement therapy. However, there are no clear guidelines regarding the optimal therapeutic doses of androgens or long-term safety data. In this study we aimed to determine if two commonly used AAS, nandrolone and stanozolol, alone or in combination with IGF-I, could activate signaling involved in breast cancer cell proliferation. Using a human breast cancer cell line, MCF-7, as an experimental model we found that both nandrolone and stanozolol caused a dose-dependent induction of aromatase expression and, consequently, estradiol production. Moreover, when nandrolone and stanozolol were combined with IGF-I, higher induction in aromatase expression was observed. This increase involved phosphatidylinositol 3-kinase (PI3K)/AKT and phospholipase C (PLC)/protein kinase C (PKC), which are part of IGF-I transductional pathways. Specifically, both AAS were able to activate membrane rapid signaling involving IGF-I receptor, extracellular regulated protein kinases 1/2 (ERK1/2) and AKT, after binding to estrogen receptor (ER), as confirmed by the ability of the ER antagonist ICI182, 780 to block such activation. The estrogenic activity of nandrolone and stanozolol was further confirmed by their capacity to induce the expression of the ER-regulated gene, CCND1 encoding for the cell cycle regulator cyclin D1, which represents a key protein for the control of breast cancer cell proliferation. In fact, when nandrolone and stanozolol were combined with IGF-I, they increased cell proliferation to levels higher than those elicited by the single factors. Taken together these data clearly indicate that the use of high doses of AAS, as occurs in doping practice, may increase the risk of breast cancer. This

  11. The role of aromatase inhibitors in ameliorating deleterious effects of ovarian stimulation on outcome of infertility treatment

    PubMed Central

    Mitwally, Mohamed FM; Casper, Robert F; Diamond, Michael P

    2005-01-01

    Clinical utilization of ovulation stimulation to facilitate the ability of a couple to conceive has not only provided a valuable therapeutic approach, but has also yielded extensive information on the physiology of ovarian follicular recruitment, endometrial receptivity and early embryo competency. One of the consequences of the use of fertility enhancing agents for ovarian stimulation has been the creation of a hyperestrogenic state, which may influence each of these parameters. Use of aromatase inhibitors reduces hyperestrogenism inevitably attained during ovarian stimulation. In addition, the adjunct use of aromatase inhibitors during ovarian stimulation reduces amount of gonadotropins required for optimum stimulation. The unique approach of reducing hyperestrogenism, as well as lowering amount of gonadotropins without affecting the number of mature ovarian follicles is an exciting strategy that could result in improvement in the treatment outcome by ameliorating the deleterious effects of the ovarian stimulation on follicular development, endometrial receptivity, as well as oocyte and embryo quality. PMID:16202169

  12. Comparing exercise responses to aerobic plus resistance training between postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy and healthy women.

    PubMed

    Paulo, Thais R S de; Winters-Stone, Kerri M; Viezel, Juliana; Rossi, Fabricio E; Aro, Bruna L; Trindade, Ana Carolina A C; Codogno, Jamile S; Freitas Junior, Ismael F

    2018-04-12

    The aim of this study was to explore whether postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy differ from healthy postmenopausal women in their response to the same aerobic + resistance training. The participants were separated into two groups: postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy for an average of 20 months (18 women) and healthy postmenopausal women (24 women). We assessed aerobic capacity (predicted maximum oxygen uptake (VO 2 max) and maximum running velocity test (Vmax)) through a walking test, upper and lower body muscle strength using an estimated one-repetition maximum test, and body composition by dual-energy X-ray absorptiometry at baseline and at three, six, and nine months, respectively. The exercise program was performed three times/week over nine months and consisted of 40 min of machine-based strength training (seated cable row, bench press, leg extension, leg press, and leg curl, as well as bridge, abdominal, and standard plank exercises) followed by 30 min of treadmill walking. Analysis of variance (ANOVA) with repeated measures was used to compare the groups over time. Postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy and healthy postmenopausal women presented similar improvements in estimated lower body strength, predicted VO 2max and V max , and body fat mass. For maximal upper body strength, there was a significant group x time interaction after six months of training (p = 0.01). The healthy postmenopausal women presented a significant increase in upper body strength after six months, while postmenopausal breast cancer survivors undergoing aromatase inhibitor therapy demonstrated an improvement only at nine months of training. The breast cancer survivors undergoing aromatase inhibitor therapy presented increased lean mass while healthy postmenopausal women maintained values over time (Breast cancer: 33.7 ± 3.9(Pre) vs. 34.1

  13. A qualitative exploration of the impact of yoga on breast cancer survivors with aromatase inhibitor-associated arthralgias.

    PubMed

    Galantino, Mary Lou; Greene, Laurie; Archetto, Benjamin; Baumgartner, Melissa; Hassall, Paula; Murphy, Joanna Kluz; Umstetter, Jamie; Desai, Krupali

    2012-01-01

    Arthralgia affects postmenopausal breast cancer survivors (BCS) receiving aromatase inhibitors (AI), which may result in reduced function and long-term well-being. This is an exploratory, qualitative investigation of BCS who participated in a yoga-based program to understand impact on joint pain and various aspects of quality of life (QOL) through a yoga program. Social cognitive theory was used and provided the foundation for developing a yoga intervention through sources of efficacy information: (1) performance accomplishment, (2) structured experience, (3) verbal support from instructor and group, and (4) physical feedback. Ten postmenopausal women with stage I-III breast cancer and AI associated arthralgia (AIAA) received yoga twice a week for eight weeks for 90 minutes and were instructed to continue in a home-based yoga program. We used social cognitive theory (SCT) to structure a yoga intervention as an ongoing physical activity to manage joint pain and function. Participants completed journal reflections on their experience and received weekly phone calls. Data was collected and analyzed using qualitative methods. Member checks were completed and emergent themes were explored and agreed upon by the research team to ensure reliability and validity of data. Several emergent themes were discovered: Empowerment: Importance of Camaraderie, Community, and Sharing; Pain Relief; Increased Physical Fitness (Energy, Flexibility, and Function); Relieved Stress/Anxiety and Transferability of Yoga through Breathing. These themes were identified through instructor observation, participant observation, and weekly phone call documentation. Participants experienced an eight-week yoga intervention as an effective physical activity and support group that fostered various improvements in quality of life (QOL) and reduction in AIAA. Participants were highly motivated to improve physical fitness levels and reduce pain. This study revealed benefits from alternative forms of

  14. Long-Term Outcome of Aromatase Inhibitor Therapy With Letrozole in Patients With Advanced Low-Grade Endometrial Stromal Sarcoma.

    PubMed

    Yamaguchi, Munekage; Erdenebaatar, Chimeddulam; Saito, Fumitaka; Motohara, Takeshi; Miyahara, Yo; Tashiro, Hironori; Katabuchi, Hidetaka

    2015-11-01

    There has been no consensus on the indications for the treatment of advanced low-grade endometrial stromal sarcoma (LGESS), and the possible effects of hormonal treatment including progestins and aromatase inhibitors have been reported. The aim of this study was to investigate the efficacy of aromatase inhibitor therapy with letrozole for patients with residual or recurrent LGESS. We retrospectively reviewed the clinical response of patients with advanced LGESS who had been treated with letrozole. We also analyzed the adverse effects after the administration of letrozole. The expression levels of estrogen receptor and aromatase in the tumors were immunohistochemically examined. In 5 patients who had been treated for unresectable LGESS lesions after initial or repeat surgical procedures, residual lesions in 3 patients and recurrence lesions in 2 patients were the indications for hormonal therapy with letrozole. The median duration of letrozole exposure at retrospective analysis was 53 (10-96) months. The clinical outcomes were classified as complete response in 2 patients, partial response in 1 patient, and stable disease in 2 patients. Myalgias, hot flashes, and arthralgias were not observed during the follow-up period in any patients. The median serum levels of estradiol were <5.0 (cutoff value, <0.5-11.8) pg/mL. The median age-matched bone mineral densities were 92% (79%-123%). The LGESS tissues in all 5 patients were positive for estrogen receptor and aromatase expression. Letrozole as well as progestins could be the first choice of treatment for patients with recurrent or residual LGESS, which is difficult to resect surgically because of its efficacy and minimal adverse effects.

  15. Social factors and aromatase gene expression during adult male-to-female sex change in captive leopard grouper Mycteroperca rosacea.

    PubMed

    Romo-Mendoza, Daniel; Campos-Ramos, Rafael; Vázquez-Islas, Grecia; Burgos-Aceves, Mario A; Esquivel-Gutiérrez, Edgar R; Guerrero-Tortolero, Danitzia A

    2018-01-25

    Social factors and aromatase gene expression in the leopard grouper Mycteroperca rosacea was studied when captive fish were separated by sex during the reproductive (April-June) and post-reproductive (July-September) seasons. Monosex females, monosex males, and mixed-sex, held in social sextet units were analyzed for sex steroids throughout confinement. At the end of the experiment, the gonad-sex was defined by histology, and gonad and brain aromatase gene expressions were quantified. Only males held in the monosex social units changed sex. Histology showed one male remained unchanged, six were found in a transitional sexual stage, in which two had intersex-predominantly-testes, and four had a more defined intersex ovo-testes pattern, and 11 were immature de novo females (neofemales). Neofemales and most intersex fish did not survive. In spring, 11-ketosterone showed a specific male profile, which suggests that male-to-female sex change was not triggered during the reproductive season. The low steroid levels in summer made it impossible to associate the sex change to a gonad hormonal shift; in September, gonad aromatase gene expression was not significantly different among groups. However, brain aromatase expression in intersex fish was significantly higher than monosex females, mixed-sex females, and neofemale groups. These results suggest that in the absence of female hormonal compounds, and at a time when male gonad steroidogenesis was diminished, the brain mediated male-to-male social-behavioral interactions, including stress, by increasing aromatization, resulting in derived intersex-male, which triggered more aromatization, followed by a sex change. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Intratumoral concentration of estrogens and clinicopathological changes in ductal carcinoma in situ following aromatase inhibitor letrozole treatment

    PubMed Central

    Takagi, K; Ishida, T; Miki, Y; Hirakawa, H; Kakugawa, Y; Amano, G; Ebata, A; Mori, N; Nakamura, Y; Watanabe, M; Amari, M; Ohuchi, N; Sasano, H; Suzuki, T

    2013-01-01

    Background: Estrogens have important roles in ductal carcinoma in situ (DCIS) of the breast. However, the significance of presurgical aromatase inhibitor treatment remains unclear. Therefore, we examined intratumoral concentration of estrogens and changes of clinicopathological factors in DCIS after letrozole treatment. Methods: Ten cases of postmenopausal oestrogen receptor (ER)-positive DCIS were examined. They received oral letrozole before the surgery, and the tumour size was evaluated by ultrasonography. Surgical specimens and corresponding biopsy samples were used for immunohistochemistry. Snap-frozen specimens were also available in a subset of cases, and used for hormone assays and microarray analysis. Results: Intratumoral oestrogen levels were significantly lower in DCIS treated with letrozole compared with that in those without the therapy. A great majority of oestrogen-induced genes showed low expression levels in DCIS treated with letrozole by microarray analysis. Moreover, letrozole treatment reduced the greatest dimension of DCIS, and significantly decreased Ki-67 and progesterone receptor immunoreactivity in DCIS tissues. Conclusion: These results suggest that estrogens are mainly produced by aromatase in DCIS tissues, and aromatase inhibitors potently inhibit oestrogen actions in postmenopausal ER-positive DCIS through rapid deprivation of intratumoral estrogens. PMID:23756858

  17. Comprehensive and Automated Linear Interaction Energy Based Binding-Affinity Prediction for Multifarious Cytochrome P450 Aromatase Inhibitors

    PubMed Central

    2017-01-01

    Cytochrome P450 aromatase (CYP19A1) plays a key role in the development of estrogen dependent breast cancer, and aromatase inhibitors have been at the front line of treatment for the past three decades. The development of potent, selective and safer inhibitors is ongoing with in silico screening methods playing a more prominent role in the search for promising lead compounds in bioactivity-relevant chemical space. Here we present a set of comprehensive binding affinity prediction models for CYP19A1 using our automated Linear Interaction Energy (LIE) based workflow on a set of 132 putative and structurally diverse aromatase inhibitors obtained from a typical industrial screening study. We extended the workflow with machine learning methods to automatically cluster training and test compounds in order to maximize the number of explained compounds in one or more predictive LIE models. The method uses protein–ligand interaction profiles obtained from Molecular Dynamics (MD) trajectories to help model search and define the applicability domain of the resolved models. Our method was successful in accounting for 86% of the data set in 3 robust models that show high correlation between calculated and observed values for ligand-binding free energies (RMSE < 2.5 kJ mol–1), with good cross-validation statistics. PMID:28776988

  18. Aromatase inhibitor regulates let-7 expression and let-7f induced cell migration in endometrial cells from women with endometriosis

    PubMed Central

    Cho, SiHyun; Mutlu, Levent; Zhou, Yuping; Taylor, Hugh S.

    2018-01-01

    Objectives To evaluate associations between aromatase inhibitor (AI) treatment and let-7 family microRNA expression in endometriosis. Design In vitro study using Ishikawa cells and human endometrial stromal cells (HESC) obtained from patients with endometriosis Setting University research center. Patients Women undergoing laparoscopic surgery for endometriosis Interventions HESCs and Ishikawa cells treated with various letrozol concentrations and transfected with a mimic of let-7 subtypes of interest Main Outcome Measures microRNAs let7a-f and aromatase expression were evaluated. Migration potential after transfection with a let-7f mimic were analyzed. Results After letrozole treatment for 48 hours, all let-7 subtypes showed a trend toward increased expression in a dose dependent manner in Ishikawa cells, and significant differences were found in let-7b and let-7f between controls and the 20 μmol/L treated groups. Further, let-7f showed significant differences between control and 1.0 μmol/L treatment group, a typical therapeutic level, in HESCs. Transfection of a let-7f mimic decreased aromatase expression in both Ishikawa cells and HESC, and led to a significant decrease in number of migrating cells in both cell types. Conclusions AI treatment significantly increased expression of let-7f in Ishikawa cells and HESCs from patient with endometriosis; increased lef-7f expression effectively reduced the migration of endometrial cells. Modulation of miRNAs involved in the pathogenesis of endometriosis may have therapeutic potential for endometriosis. PMID:27320036

  19. Analysis of Obesity-Related Factors and their Association with Aromatase Expression in Canine Malignant Mammary Tumours.

    PubMed

    Shin, J-I; Lim, H-Y; Kim, H-W; Seung, B-J; Ju, J-H; Sur, J-H

    2016-07-01

    This study was designed to investigate the role of obesity in canine malignant mammary tumours (CMMTs), by assessing aromatase expression and the regulatory roles of immune mediators such as cyclo-oxygenase-2 (COX2), prostaglandin E2 (PGE2), nuclear factor kappa beta (NF-κB), hypoxia inducible factor-1α (HIF-1α) and adipokines (i.e. leptin) in lean, optimal body weight, overweight and obese animals. Clinicopathological data, including the breed, body weight, body condition score and age and neutering status, were collected, together with histopathological characteristics (i.e. histological types, grading and lymphatic invasion). To determine the expression of each factor, immunohistochemistry was conducted with 60 samples of malignant CMMTs. CMMTs from overweight and obese animals had significantly elevated levels of PGE2, and aromatase expression correlated significantly with PGE2, NF-κB and leptin expression. However, no significant difference was observed in terms of histopathological characteristics. The results suggest that PGE2, a known obesity-related immune mediator, could be upregulated in CMMTs from overweight and obese animals. In addition, PGE2, NF-κB and leptin influenced the expression of aromatase, as observed in women. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Targeting the receptor tyrosine kinase RET in combination with aromatase inhibitors in ER positive breast cancer xenografts.

    PubMed

    Andreucci, Elena; Francica, Paola; Fearns, Antony; Martin, Lesley-Ann; Chiarugi, Paola; Isacke, Clare M; Morandi, Andrea

    2016-12-06

    The majority of breast cancers are estrogen receptor positive (ER+). Blockade of estrogen biosynthesis by aromatase inhibitors (AIs) is the first-line endocrine therapy for post-menopausal women with ER+ breast cancers. However, AI resistance remains a major challenge. We have demonstrated previously that increased GDNF/RET signaling in ER+ breast cancers promotes AI resistance. Here we investigated the efficacy of different small molecule RET kinase inhibitors, sunitinib, cabozantinib, NVP-BBT594 and NVP-AST487, and the potential of combining a RET inhibitor with the AI letrozole in ER+ breast cancers. The most effective inhibitor identified, NVP-AST487, suppressed GDNF-stimulated RET downstream signaling and 3D tumor spheroid growth. Ovariectomized mice were inoculated with ER+ aromatase-overexpressing MCF7-AROM1 cells and treated with letrozole, NVP-AST487 or the two drugs in combination. Surprisingly, the three treatment regimens showed similar efficacy in impairing MCF7-AROM1 tumor growth in vivo. However in vitro, NVP-AST487 was superior to letrozole in inhibiting the GDNF-induced motility and tumor spheroid growth of MCF7-AROM1 cells and required in combination with letrozole to inhibit GDNF-induced motility in BT474-AROM3 aromatase expressing cells. These data indicate that inhibiting RET is as effective as the current therapeutic regimen of AI therapy but that a combination treatment may delay cancer cell dissemination and metastasis.

  1. Effects of bisphenol A on the expression of cytochrome P450 aromatase (CYP19) in human fetal osteoblastic and granulosa cell-like cell lines.

    PubMed

    Watanabe, Masatada; Ohno, Shuji; Nakajin, Shizuo

    2012-04-05

    The effects of bisphenol A (BPA), an endocrine disruptor, on aromatase (CYP19) expression in human osteoblastic (SV-HFO) and ovarian granulosa-like (KGN) cell lines were examined. CYP19 enzyme activity was suppressed in the presence of BPA in a dose-dependent fashion in both cell lines. CYP19 gene transcript expression, as well as activities of promoter I.4 in SV-HFO and promoter II in KGN, was down-regulated by BPA, suggesting that BPA affects CYP19 at the gene-expression level. These data and the previous finding that BPA induced the down-regulation of promoter I.1 activity within the human placental cell line suggest that there may be a conserved signaling pathway that down-regulates CYP19 expression in response to BPA in both cell lines. Additionally, differences between promoter I.4 and II suggest that there may be cell- and promoter-specific down-regulating mechanisms downstream from the actions of BPA. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  2. Randomized Controlled Trial of a Home‐Based Walking Program to Reduce Moderate to Severe Aromatase Inhibitor‐Associated Arthralgia in Breast Cancer Survivors

    PubMed Central

    Callahan, Leigh F.; Cleveland, Rebecca J.; Arbeeva, Liubov L.; Hackney, Betsy S.; Muss, Hyman B.

    2017-01-01

    Abstract Background. In postmenopausal women diagnosed with breast cancer (BC), most BC tumors are hormone receptor positive and guidelines recommend adjuvant endocrine therapy that includes an aromatase inhibitor (AI). This study investigates the impact of a 6‐week, home‐based, self‐directed walking program on the commonly reported side effect of AI‐associated arthralgia (AIAA). Materials and Methods. In this phase II trial, consented BC patients were randomized to walking Intervention (n = 31) or Wait List Control (WLC; n = 31). Eligibility criteria included: stage 0–III BC, on AI for at least 4 weeks, ≥3 on a 5‐point scale inquiring about joint symptom intensity “at its worst,” and exercising ≤150 minutes per week. Outcomes were self‐reported joint symptoms and psychosocial measures. Analyses comparing Intervention and WLC groups were conducted on an intention‐to‐treat basis to assess intervention impact at 6 weeks (postintervention) and at 6‐months follow‐up. Adjusted means were calculated to assess differences in two groups. Results. In our final sample (n = 62), mean age was 64 years, 74% were white, and 63% had a body mass index of 30 or higher. At postintervention, Intervention group participants reported significantly increased walking minutes per week, reduced stiffness, less difficulty with activities of daily living (ADL), and less perceived helplessness in managing joint symptoms. At 6‐months follow‐up (postwalking period in both Intervention and WLC), walking minutes per week had decreased significantly; however, improvements in stiffness and difficulty with ADLs were maintained. Conclusion. This study adds to the growing evidence base suggesting exercise as a safe alternative or adjunct to medications for the management of AIAA. Implications for Practice. Breast cancer survivors whose adjuvant endocrine treatment includes an aromatase inhibitor (AI) often experience the side effect of AI

  3. Multiple splicing events involved in regulation of human aromatase expression by a novel promoter, I.6.

    PubMed

    Shozu, M; Zhao, Y; Bulun, S E; Simpson, E R

    1998-04-01

    The expression of aromatase is regulated in a tissue-specific fashion through alternative use of multiple promoter-specific first exons. To date, eight different first exons have been reported in human aromatase, namely I.1., I.2, I.3. I.4, I.5, PII, 2a, and 1f. Recently, we have found a new putative exon I in a RACE-generated library of THP-1 cells and have conducted studies to characterize this new exon I. We confirmed that the constructs containing -1552/+17 or less flanking sequence of this exon function as a promoter in THP-1 cells, JEG-3 cells and osteoblast-like cells obtained from a human fetus. Results of transfection assays using a series of deletion constructs and mutation constructs indicate that a 1-bp mismatch of the consensus TATA-like box (TTTAAT) and the consensus sequence of the initiator site, which is located 45 bp downstream of the putative TATA box, were functioning cooperatively as a core promoter. The putative transcription site was confirmed by the results of RT-PCR southern blot analysis. We examined the regulation and the expression of this exon, I.6, in several human cells and tissues by RT-PCR Southern blot analysis. THP-1 cells (mononuclear leukemic origin) and JEG-3 cells (choriocarcinoma origin) expressed exon I.6 in serum-free media. The level of expression was increased by serum and phorbol myristyl acetate (PMA) in both cell lines. Adipose stromal cells also expressed exon I.6 in the presence of PMA. In fetal osteoblasts, the expression of exon I.6 was increased most effectively by serum and less so by dexamethasone (DEX) + IL-1beta and DEX + IL-11, whereas induction by serum was suppressed by the addition of DEX. The level of expression was low in granulosa cells in culture and did not change with forskolin. On the other hand, dibutyryl cAMP suppressed PMA-stimulated expression of exon I.6 in THP-1 cells and adipose stromal cells. This result supports the hypothesis that the expression of exon I.6 is regulated mainly via an AP-1

  4. A Pilot Study of Website Information Regarding Aromatase Inhibitors: Dietary Supplement Interactions

    PubMed Central

    McDermott, Cara L.; Hsieh, Angela A.; Sweet, Erin S.; Tippens, Kimberly M.

    2011-01-01

    Abstract Objectives Patients who have hormone receptor–positive breast cancer and who are taking aromatase inhibitors (AIs) should understand the benefits and risks of concomitant dietary supplement (DS) use. The International Society for Integrative Oncology (SIO) encourages patients to discuss DS use with their health care practitioners. The objective was to conduct a pilot study rating Internet websites from the perspective of health care practitioners for information about AI–DS interactions. Design Five (5) Internet websites suggested by SIO were evaluated using the DISCERN instrument rating tool. The available AI–DS information on these websites was rated by 4 evaluators: 2 naturopathic doctors, 1 oncology pharmacy resident, and a pharmacy student. Results The overall rankings ranged from 1.6 to 3.9, with considerable variability in the type of information available from the websites. The interevaluator rankings of the websites ranged from 0.44 to 0.89. The evaluators consistently found the most reliable, unbiased, and comprehensive information on AI–DS interactions at the Natural Medicines Comprehensive Database and Memorial Sloan-Kettering Cancer Center websites. However, more than one database was needed for provision of optimal patient information on AI–DS interactions. Conclusions In order to effectively advise patients regarding AI–DS interactions, more than one website should be evaluated to assess the potential efficacy and safety of DS in women whose breast cancer is being treated with an AI. PMID:22087614

  5. SGK3 sustains ERα signaling and drives acquired aromatase inhibitor resistance through maintaining endoplasmic reticulum homeostasis.

    PubMed

    Wang, Yuanzhong; Zhou, Dujin; Phung, Sheryl; Warden, Charles; Rashid, Rumana; Chan, Nymph; Chen, Shiuan

    2017-02-21

    Many estrogen receptor alpha (ERα)-positive breast cancers initially respond to aromatase inhibitors (AIs), but eventually acquire resistance. Here, we report that serum- and glucocorticoid-inducible kinase 3 (SGK3), a kinase transcriptionally regulated by ERα in breast cancer, sustains ERα signaling and drives acquired AI resistance. SGK3 is up-regulated and essential for endoplasmic reticulum (EnR) homeostasis through preserving sarcoplasmic/EnR calcium ATPase 2b (SERCA2b) function in AI-resistant cells. We have further found that EnR stress response down-regulates ERα expression through the protein kinase RNA-like EnR kinase (PERK) arm, and SGK3 retains ERα expression and signaling by preventing excessive EnR stress. Our study reveals regulation of ERα expression mediated by the EnR stress response and the feed-forward regulation between SGK3 and ERα in breast cancer. Given SGK3 inhibition reduces AI-resistant cell survival by eliciting excessive EnR stress and also depletes ERα expression/function, we propose SGK3 inhibition as a potential effective treatment of acquired AI-resistant breast cancer.

  6. Comparative study on individual aromatase inhibitors on cardiovascular safety profile: a network meta-analysis

    PubMed Central

    Zhao, Xihe; Liu, Lei; Li, Kai; Li, Wusheng; Zhao, Li; Zou, Huawei

    2015-01-01

    The third-generation aromatase inhibitors (AIs: anastrozole, letrozole, and exemestane) have now become standard adjuvant endocrine treatment for postmenopausal estrogen receptor-positive breast cancer complementing chemotherapy and surgery. Because of the absence of direct head-to-head comparisons of these AIs, an indirect comparison is needed for individual treatment choice. In this network systemic assessment, the cardiovascular (CV) side effects in using anastrozole, letrozole, and exemestane based on original studies on AIs vs placebo or tamoxifen were compared. We integrated all available direct and indirect evidences. The odds ratio (OR) of severe CV events for indirect comparisons between exemestane and anastrozole was 1.41 (95% confidence interval [CI] =0.49–2.78), letrozole and anastrozole was 1.80 (95% CI =0.40–3.92), and letrozole and exemestane was 1.46 (95% CI =0.34–3.4). OR of subgroup risk for AIs and tamoxifen were all >1 except for thrombolism risk subgroup. The results showed that the total and severe CV risk ranking is letrozole, exemestane, and anastrozole in descending order. None of the AIs showed advantages in CV events than tamoxifen except for thromboembolism event incidence. PMID:26491345

  7. Vaginal Testosterone for Management of Aromatase Inhibitor-Related Sexual Dysfunction: An Integrative Review.

    PubMed

    Lemke, Emily A; Madsen, Lydia T; Dains, Joyce E

    2017-05-01

    Women taking aromatase inhibitors (AIs) as part of the management of hormone receptor-positive breast cancer experience more symptoms of sexual dysfunction, including vaginal atrophy, as opposed to postmenopausal women and women treated with tamoxifen (Nolvadex®). Vaginal testosterone could be an alternative to estrogen, which is contraindicated in this population.
. A systematic review was completed by searching PubMed and Scopus databases.
. 64 search results were reduced to a final sample of 3 articles after applying inclusion and exclusion criteria.
. Published results suggest that vaginally applied testosterone doses of 150 mcg and 300 mcg improve symptoms of sexual dysfunction in women taking AIs. Minimal side effects are observed, and estradiol levels are not affected by vaginally applied testosterone. Additional research is needed to evaluate vaginal testosterone in women taking AIs.
. Vaginal testosterone shows preliminary promise as an option to manage sexual side effects of AI therapy in postmenopausal cancer survivors; however, available data are too limited to draw practice-changing conclusions.
. Large-scale randomized, controlled trials need to be completed to evaluate the efficacy and safety of vaginal testosterone in women taking AIs.

  8. Menopausal-type symptoms among breast cancer patients on aromatase inhibitor therapy.

    PubMed

    Gallicchio, L; MacDonald, R; Wood, B; Rushovich, E; Helzlsouer, K J

    2012-08-01

    To examine self-reported menopausal-type symptoms among breast cancer patients on aromatase inhibitors (AIs) compared to women of the same age who had not been diagnosed with cancer, and to determine whether the percentage of breast cancer patients experiencing these symptoms changed over the first 6 months of AI treatment. Data from a 6-month cohort study of 100 breast cancer patients initiating AI therapy and of 200 women of a similar age without a history of cancer were analyzed. At baseline (prior to the initiation of AI therapy among the breast cancer patients), 3 months, and 6 months, a comprehensive questionnaire was administered to participants that ascertained data on the experiencing of specific menopausal-type symptoms. The data showed statistically significant increases in the prevalence of certain symptoms from baseline to either follow-up point among the breast cancer patients; these symptoms included hot flushes, night sweats, pain during intercourse, hair loss, forgetfulness, depression, difficulty falling asleep, and interrupted sleep. Additionally, breast cancer patients were more likely than the women in the comparison group to report the new onset of many of these same symptoms during the follow-up time period. Because bothersome symptoms and side-effects are a major reason for discontinuation and non-adherence to treatment, symptoms should be monitored and addressed by oncologists so that the breast cancer patient can maintain her quality of life and remain adherent to the treatment schedule.

  9. Epigenetic Control of Gonadal Aromatase (cyp19a1) in Temperature-Dependent Sex Determination of Red-Eared Slider Turtles

    PubMed Central

    Matsumoto, Yuiko; Buemio, Alvin; Chu, Randy; Vafaee, Mozhgon; Crews, David

    2013-01-01

    In the red-eared slider turtle (Trachemys scripta), a species with temperature-dependent sex determination (TSD), the expression of the aromatase gene during gonad development is strictly limited to the female-producing temperature. The underlying mechanism remains unknown. In this study, we identified the upstream 5′-flanking region of the aromatase gene, gonad-specific promoter, and the temperature-dependent DNA methylation signatures during gonad development in the red-eared slider turtle. The 5′-flanking region of the slider aromatase exhibited sequence similarities to the aromatase genes of the American alligator, chicken, quail, and zebra finch. A putative TATA box was located 31 bp upstream of the gonad-specific transcription start site. DNA methylation at the CpG sites between the putative binding sites of the fork head domain factor (FOX) and vertebrate steroidogenic factor 1 (SF1) and adjacent TATA box in the promoter region were significantly lower in embryonic gonads at the female-producing temperature compared the male-producing temperature. A shift from male- to female-, but not from female- to male-, producing temperature changed the level of DNA methylation in gonads. Taken together these results indicate that the temperature, particularly female-producing temperature, allows demethylation at the specific CpG sites of the promoter region which leads the temperature-specific expression of aromatase during gonad development. PMID:23762231

  10. Tamoxifen and Aromatase Inhibitors: Cognitive Function in Occupationally Active Breast Cancer Survivors

    DTIC Science & Technology

    2010-05-04

    assessments of cognitive function and sedation in patients with cancer pain admitted to a palliative care unit. Palliative Medicine, 16 (6), 513-9. 71...interventions. Palliative & Supportive Care, 5(3), 273-280. 72 Noblett, K.L., & Swain, R.A. (2003). Pretraining enhances recovery from visuospatial...Self-reported cognitive problems in women receiving adjuvant endocrine therapy for breast cancer. Eurpoean Journal of Oncology Nursing , 11(1), 6

  11. Sex-different effects of tributyltin on brain aromatase, estrogen receptor and retinoid X receptor gene expression in rockfish (Sebastiscus marmoratus).

    PubMed

    Zhang, Jiliang; Zuo, Zhenghong; Zhu, Wenwen; Sun, Ping; Wang, Chonggang

    2013-09-01

    Since the brain plays important roles in reproduction, the brain aromatase (Cyp19b), estrogen receptor (ER), retinoid X receptor (RXR) α and peroxisome proliferator-activated receptor γ were examined in rockfish after TBT exposure (1, 10, and 100 ng L(-1)). The results showed that the Cyp19b expression was elevated in the male rockfish, while no effect was produced in the females. Inconsistently, serum testosterone and 17β-estradiol showed no change in the males, while an increase of testosterone and a decrease of 17β-estradiol were observed in the females. TBT affected the ER expression in the males depending on the concentrations, however, no change was observed in the females. In addition, TBT elevated the RXRα expression in the males but produced an opposite effect in the females. In conclusion, TBT might have had sex-different effects on the brain Cyp19b, ER and RXR expression in rockfish, indicating a complex endocrine disrupting effect of TBT. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Influence of the membrane lipophilic environment on the structure and on the substrate access/egress routes of the human aromatase enzyme. A computational study.

    PubMed

    Sgrignani, Jacopo; Magistrato, Alessandra

    2012-06-25

    Human aromatase (HA), an enzyme located on the membrane of the endoplasmatic reticulum, is of crucial biological importance in the biosynthesis of estrogens. High levels of estrogens are related with important pathologies, conferring to HA a key role as a pharmacological target. In this study we provide, for the first time, an atomistic model of HA embedded on a membrane model to understand the influence of the membrane lipophilic environment on the structural and dynamical properties of HA and on the access/egress pathways of the substrate (androstenedione, ASD) and of the oxygen molecule (involved in the enzymatic process) into/from the HA active site. To this end we used several computational techniques such as force field-based molecular dynamics (MD) simulations, Random Expulsion MD, Steered MD, and Implicit Ligand Sampling. Our results show that the membrane anchoring does not markedly affect the structural properties and the flexibility of the protein, but they clearly point out that the membrane has a marked effect on the access/egress routes of the reactants, stabilizing the formation of different channels for both ASD and O(2) with respect to those observed in pure water solution. Due to the importance of HA in medicine and since access/egress channels may influence its substrate selectivity, a detailed understanding of the role of the membrane in shaping these channels may be of valuable help in drug design.

  13. Ectopic expression of H2AX protein promotes TrkA-induced cell death via modulation of TrkA tyrosine-490 phosphorylation and JNK activity upon DNA damage

    SciTech Connect

    Jung, Eun Joo; Kim, Deok Ryong, E-mail: drkim@gnu.ac.kr

    2011-01-21

    Research highlights: {yields} We established TrkA-inducible U2OS cells stably expressing GFP-H2AX proteins. {yields} GFP-H2AX was colocalized with TrkA in the cytoplasm. {yields} {gamma}H2AX production was significantly increased upon activation of TrkA and suppressed by TrkA inhibitor or JNK inhibitor. {yields} Ectopic expression of H2AX promoted TrkA-mediated cell death through the modulation of TrkA tyrosine-490 phosphorylation and JNK activity upon DNA damage. -- Abstract: We previously reported that TrkA overexpression causes accumulation of {gamma}H2AX proteins in the cytoplasm, subsequently leading to massive cell death in U2OS cells. To further investigate how cytoplasmic H2AX is associated with TrkA-induced cell death, we establishedmore » TrkA-inducible cells stably expressing GFP-tagged H2AX. We found that TrkA co-localizes with ectopically expressed GFP-H2AX proteins in the cytoplasm, especially at the juxta-nuclear membranes, which supports our previous results about a functional connection between TrkA and {gamma}H2AX in TrkA-induced cell death. {gamma}H2AX production from GFP-H2AX proteins was significantly increased when TrkA was overexpressed. Moreover, ectopic expression of H2AX activated TrkA-mediated signal pathways via up-regulation of TrkA tyrosine-490 phosphorylation. In addition, suppression of TrkA tyrosine-490 phosphorylation under a certain condition was removed by ectopic expression of H2AX, indicating a functional role of H2AX in the maintenance of TrkA activity. Indeed, TrkA-induced cell death was highly elevated by ectopic H2AX expression, and it was further accelerated by DNA damage via JNK activation. These all results suggest that cytoplasmic H2AX could play an important role in TrkA-mediated cell death by modulating TrkA upon DNA damage.« less

  14. Isolation of chicken homolog of the FOXL2 gene and comparison of its expression patterns with those of aromatase during ovarian development.

    PubMed

    Govoroun, Marina S; Pannetier, Maëlle; Pailhoux, Eric; Cocquet, Julie; Brillard, Jean-Pierre; Couty, Isabelle; Batellier, Florence; Cotinot, Corinne

    2004-12-01

    Mutations in the forkhead transcription factor gene FOXL2 are involved in ovarian failure, which occurs in human BPES syndrome. This syndrome presents a sexually dimorphic expression, specific to the ovary in several vertebrates. We cloned the open reading frame of chicken FOXL2 (cFoxL2) and studied cFoxL2 expression in developing gonads and during adulthood to examine the role of FOXL2 in ovarian differentiation and function in birds. The spatial and temporal dynamics of cFoxL2 and aromatase expression were analyzed in parallel by using real-time quantitative reverse transcriptase-polymerase chain reaction and immunohistochemistry in attempt to investigate the possible role of cFoxL2 in the regulation of aromatase. The expression patterns of cFoxL2 and aromatase transcripts were highly correlated during the sex-differentiation period (4.7-12.7 days of incubation). Aromatase and cFoxL2 proteins were colocalized in the medullar part of female gonads on embryonic day 14. Fourteen days after hatching, cFoxL2 protein was mainly detected in granulosa cells of developing follicles. In adult ovary follicular envelopes, apart from granulosa cells, cFoxL2 transcript and protein were detected at lower levels in theca cells where aromatase was present. A high level of cFoxL2 transcription was also observed in maturing and ovulated oocytes. Our results confirm that FoxL2 is an early regulator of ovarian development in birds and may be involved in aromatase transcription regulation. Copyright (c) 2004 Wiley-Liss, Inc.

  15. Reduced estradiol synthesis by letrozole, an aromatase inhibitor, is protective against development of pentylenetetrazole-induced kindling in mice.

    PubMed

    Rashid, Davood; Panda, B P; Vohora, Divya

    2015-11-01

    Neurosteroids, such as testosterone and their metabolites, are known to modulate neuronal excitability. The enzymes regulating the metabolism of these neurosteroids, thus, may be targeted as a noval strategy for the development of new antiepileptic drugs. The present work targeted two such enzymes i,e aromatase and 5α-reductase in order to explore the potential of letrozole (an aromatase inhibitor) on pentylenetetrazole (PTZ)-induced kindling in mice and the ability of finasteride (a 5α-reductase inhibitor) to modulate any such effects. PTZ (30 mg/kg, i.p.), when administered once every two days (for a total of 24 doses) induced kindling in Swiss albino mice. Letrozole (1 mg/kg, p.o.), administered prior to PTZ, significantly reduced the % incidence of kindling, delayed mean onset time of seizures and reduced seizure severity score. Letrozole reduced the levels of plasma 17β-estradiol after induction of kindling. The concurrent administration of finasteride and letrozole produced effects similar to letrozole on PTZ-kindling and on estradiol levels. This implies that the ability of letrozole to redirect the synthesis of dihydrotestosterone (DHT) and 5α-androstanediol from testosterone doesn't appear to play a significant role in the protective effects of letrozole against PTZ kindling. Letrozole, however, increased the levels of 5α-DHT in mice plasma. The aromatase inhibitors, thus, may be exploited for inhibiting the synthesis of proconvulsant (17β-estradiol) and/or redirecting the synthesis of anticonvulsant (DHT and 5α-androstanediol) neurosteroids. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. A nude mouse model of obesity to study the mechanisms of resistance to aromatase inhibitors.

    PubMed

    Schech, Amanda; Yu, Stephen; Goloubeva, Olga; McLenithan, John; Sabnis, Gauri

    2015-08-01

    Obesity is a risk factor for breast cancer progression. Breast cancer patients who are overweight or obese or have excess abdominal fat have an increased risk of local or distant recurrence and cancer-related death. Hormone depletion therapies can also cause weight gain, exacerbating the risk for these patients. To understand the effect of obesity on hormone-dependent human breast cancer tumors, we fed ovariectomized athymic nude mice a diet containing 45% kcal fat and 17% kcal sucrose (high fat sucrose diet (HFSD)), 10% kcal fat (low fat diet (LFD)), or a standard chow diet (chow). The mice fed the HFSD developed metabolic abnormalities consistent with the development of obesity such as weight gain, high fasting blood glucose, and impaired glucose tolerance. These mice also developed hyperinsulinemia and insulin resistance. The obese mice also had a higher tumor growth rate compared to the lean mice. Furthermore, the obese mice showed a significantly reduced responsiveness to letrozole. To understand the role of obesity in this reduced responsiveness, we examined the effect of insulin on the growth of MCF-7Ca cells in response to estrogen or letrozole. The presence of insulin rendered MCF-7Ca cells less responsive to estrogen and letrozole. Exogenous insulin treatment of MCF-7Ca cells also resulted in increased p-Akt as well as ligand-independent phosphorylation of ERα. These findings suggest that diet-induced obesity may result in reduced responsiveness of tumors to letrozole due to the development of hyperinsulinemia. We conclude that obesity influences the response and resistance of breast cancer tumors to aromatase inhibitor treatment. © 2015 Society for Endocrinology.

  17. Aromatase inhibitors augment nociceptive behaviors in rats and enhance the excitability of sensory neurons

    PubMed Central

    Robarge, Jason D.; Duarte, Djane B.; Shariati, Behzad; Wang, Ruizhong; Flockhart, David A.; Vasko, Michael R.

    2016-01-01

    Although aromatase inhibitors (AIs) are commonly used therapies for breast cancer, their use is limited because they produce arthralgia in a large number of patients. To determine whether AIs produce hypersensitivity in animal models of pain, we examined the effects of the AI, letrozole, on mechanical, thermal, and chemical sensitivity in rats. In ovariectomized (OVX) rats, administering a single dose of 1 or 5 mg/kg letrozole significantly reduced mechanical paw withdrawal thresholds, without altering thermal sensitivity. Repeated injection of 5 mg/kg letrozole in male rats produced mechanical, but not thermal, hypersensitivity that extinguished when drug dosing was stopped. A single dose of 5 mg/kg letrozole or daily dosing of letrozole or exemestane in male rats also augmented flinching behavior induced by intraplantar injection of 1000 nmol of adenosine 5′-triphosphate (ATP). To determine whether sensitization of sensory neurons contributed to AI-induced hypersensitivity, we evaluated the excitability of neurons isolated from dorsal root ganglia of male rats chronically treated with letrozole. Both small and medium-diameter sensory neurons isolated from letrozole-treated rats were more excitable, as reflected by increased action potential firing in response to a ramp of depolarizing current, a lower resting membrane potential, and a lower rheobase. However, systemic letrozole treatment did not augment the stimulus-evoked release of the neuropeptide calcitonin gene-related peptide (CGRP) from spinal cord slices, suggesting that the enhanced nociceptive responses were not secondary to an increase in peptide release from sensory endings in the spinal cord. These results provide the first evidence that AIs modulate the excitability of sensory neurons, which may be a primary mechanism for the effect of these drugs to augment pain behaviors in rats. PMID:27072527

  18. Efficacy of exemestane after nonsteroidal aromatase inhibitor use in metastatic breast cancer patients.

    PubMed

    Kim, Sun Hye; Park, In Hae; Lee, Hyewon; Lee, Keun Seok; Nam, Byung-Ho; Ro, Jungsil

    2012-01-01

    Previous studies have suggested a lack of complete cross-resistance between steroidal (exemestane) and non-steroidal aromatase inhibitors (nSAI). Eighty-eight metastatic breast cancer (MBC) patients who received 25 mg of exemestane orally once a day at the National Cancer Center, Korea, between 2003 and 2009, were reviewed retrospectively. All patients had received nSAI for metastatic disease prior to exemestane therapy. The median age was 52 years (range, 33-79), and 13 (14.8%) patients were premenopausal who concomitantly received GnRH agonist. Exemestane was given as a second- (80.7%) or third-line (19.3%) hormone therapy. The clinical benefit (CB) rate (complete response + partial response + stable disease ≥ 24 weeks) was 30.7%, with a median CB duration of 10.0 months (range, 6.3-78.7). The median progression-free survival (PFS) was 3.0 months (95% confidence interval [CI], 1.99-4.01) and the overall survival (OS) 21.5 months (95% CI, 17.96-25.04), with a median follow-up of 50.3 months. Patients who achieved CB had longer OS than those patients who did not (29.6 vs 17.9 months; P = 0.002). On univariate analysis of predictive factors, patients who had achieved CB from previous nSAI tended to show lower CB rate (24.6% vs 44.4%, respectively; P = 0.063) and shorter PFS (2.8 vs 4.8 months, respectively; p = 0.233) than patients who had not. Achieving CB from previous nSAI became independent predictive factor for CBR to exemestane on multivariable analysis (Odds ratio = 2.852, P = 0.040). Exemestane after nSAI failure was effective in prolonging CB duration. The drug's efficacy seemed to be inferior in patients who had benefit from previous nSAI use.

  19. Efficacy of Exemestane in Korean Patients with Metastatic Breast Cancer after Failure of Nonsteroidal Aromatase Inhibitors

    PubMed Central

    Lee, June Koo; Lee, Daewon; Kim, Ji-Yeon; Lim, Yoojoo; Lee, Eunyoung; Moon, Hyeong-Gon; Kim, Tae-Yong; Han, Sae-Won; Oh, Do-Youn; Lee, Se-Hoon; Han, Wonshik; Kim, Dong-Wan; Kim, Tae-You; Noh, Dong-Young

    2013-01-01

    Purpose Exemestane has shown good efficacy and tolerability in postmenopausal women with hormone receptor-positive metastatic breast cancer. However, clinical outcomes in Korean patients have not yet been reported. Methods Data on 112 postmenopausal women with metastatic breast cancer were obtained retrospectively. Clinicopathological characteristics and treatment history were extracted from medical records. All patients received 25 mg exemestane daily until objective disease progression. Progression-free survival (PFS) was the primary endpoint, and secondary endpoints were overall survival (OS), objective response rate (ORR), and clinical benefit rate (CBR=complete response+partial response+stable disease for 6 months). Results The median age of the subjects was 55 years (range, 28-76 years). Exemestane treatment resulted in a median PFS of 5.7 months (95% confidence interval [CI], 4.4-7.0 months) and median OS of 21.9 months (95% CI, 13.6-30.3 months). ORR was 6.4% and CBR was 46.4% for the 110 patients with evaluable lesions. Symptomatic visceral disease was independently associated with shorter PFS (hazard ratio, 3.611; 95% CI, 1.904-6.848; p<0.001), compared with bone-dominant disease in a multivariate analysis of PFS after adjusting for age, hormone receptor, human epidermal growth factor receptor 2, Ki-67 status, dominant metastasis site, and sensitivity to nonsteroidal aromatase inhibitor (AI) treatment. Sensitivity to previous nonsteroidal AI treatment was not associated with PFS, suggesting no cross-resistance between exemestane and nonsteroidal AIs. Conclusion Exemestane was effective in postmenopausal Korean women with hormone receptor-positive metastatic breast cancer who failed previous nonsteroidal AI treatment. PMID:23593084

  20. Red Versus White Wine as a Nutritional Aromatase Inhibitor in Premenopausal Women: A Pilot Study

    PubMed Central

    Shufelt, Chrisandra; Merz, C. Noel Bairey; Yang, YuChing; Kirschner, Joan; Polk, Donna; Stanczyk, Frank; Paul-Labrador, Maura

    2012-01-01

    Abstract Background An increased risk of breast cancer is associated with alcohol consumption; however, it is controversial whether red wine increases this risk. Aromatase inhibitors (AIs) prevent the conversion of androgens to estrogen and occur naturally in grapes, grape juice, and red, but not white wine. We tested whether red wine is a nutritional AI in premenopausal women. Methods In a cross-over design, 36 women (mean age [SD], 36 [8] years) were assigned to 8 ounces (237 mL) of red wine daily then white wine for 1 month each, or the reverse. Blood was collected twice during the menstrual cycle for measurement of estradiol (E2), estrone (E1), androstenedione (A), total and free testosterone (T), sex hormone binding globulin (SHBG), luteinizing hormone (LH), and follicle stimulating hormone (FSH). Results Red wine demonstrated higher free T vs. white wine (mean difference 0.64 pg/mL [0.2 SE], p=0.009) and lower SHBG (mean difference −5.0 nmol/L [1.9 SE], p=0.007). E2 levels were lower in red vs. white wine but not statistically significant. LH was significantly higher in red vs. white wine (mean difference 2.3 mIU/mL [1.3 SE], p=0.027); however, FSH was not. Conclusion Red wine is associated with significantly higher free T and lower SHBG levels, as well as a significant higher LH level vs. white wine in healthy premenopausal women. These data suggest that red wine is a nutritional AI and may explain the observation that red wine does not appear to increase breast cancer risk. PMID:22150098

  1. Survival benefit of tamoxifen and aromatase inhibitor in male and female breast cancer.

    PubMed

    Eggemann, Holm; Altmann, Udo; Costa, Serban-Dan; Ignatov, Atanas

    2018-02-01

    Our goal was to compare the survival advantage of tamoxifen (TAM) and aromatase inhibitor (AI) in female (FBC) and male breast cancer (MBC). We performed a retrospective study of 2785 FBC and 257 MBC patients treated with hormonal therapy. The median follow-up was 106 months (range 3-151 months) and 42 months (range 2-115 months) for FBC and MBC, respectively. The patients were divided into two groups according to the hormonal therapy used: TAM-treated and AI-treated. MBC was characterized by older age, advanced tumor stage, and higher rate of lymph node metastases, in comparison with FBC. Matching analysis was performed using six prognostic criteria: patient age, tumor stage, tumor grade, lymph node status, human epidermal growth factor receptor (HER2) status, and administration of chemotherapy. The female and male patients were matched 2:1. In this analysis, 316 women and 158 men treated with TAM, and 60 women and 30 men treated with AI, were included. The overall survival (OS) was estimated by the Kaplan-Meier method and was compared between FBC and MBC. TAM-treated FBC and MBC patients had similar 5-year OS, 85.1 and 89.2%, respectively (p = 0.972). Notably, FBC patients treated with AI had significantly greater 5-year OS (85.0%) in comparison with AI-treated MBC patients (5-year OS of 73.3%; p = 0.028). The OS of TAM-treated patients with MBC was similar to the OS of TAM-treated FBC patients, whereas AI treatment is associated with poorer survival of MBC patients.

  2. Impact of Aromatase Genetic Variation on Hormone Levels and Global Outcome after Severe TBI

    PubMed Central

    Garringer, Julie A.; Niyonkuru, Christian; McCullough, Emily H.; Loucks, Tammy; Dixon, C. Edward; Conley, Yvette P.; Berga, Sarah

    2013-01-01

    Abstract Although experimental traumatic brain injury (TBI) studies support estradiol as a neuroprotectant and potent stimulator of neuroplasticity, clinical studies suggest a negative association between endogenous estradiol profiles and mortality/poor outcomes. However, no studies have evaluated associations with cerebral spinal fluid (CSF) hormone profiles and aromatase gene (cytochrome P450 [CYP]19A1) variability on clinical TBI outcomes. We evaluated 110 adults with severe TBI. Average and daily estradiol, testosterone, and estradiol/testosterone ratios (E2:T) were measured using CSF and serum samples and compared to healthy controls. Eighteen tagging and four functional single-nucleotide polymorphisms (SNPs) for CYP19A1 were genotyped and compared to hormones, acute mortality, and Glasgow Outcome Scale (GOS) scores 6 months post-TBI. TBI subjects had lower CSF estradiol over time versus controls. CSF testosterone was initially high, but declined over time. E2/T ratios were initially low, compared to controls, but rose over time. Higher mean E2/T ratio in bivariate analysis was associated with lower mortality (p=0.019) and better GOS-6 scores (p=0.030). rs2470152 influenced CSF E2/T ratio and also serum and CSF testosterone (p≤0.05 all comparisons). Multiple-risk SNPs rs2470152, rs4646, and rs2470144 were associated with worse GOS-6 scores (p≤0.05, all comparisons), and those with>1 risk SNP variant had a higher risk for poor outcome, compared with those with ≤1 risk variant. TBI results in low CSF estradiol and dynamic CSF testosterone and E2/T ratio. In contrast to clinical serum hormone studies, higher CSF E2/T ratio was associated with better outcome. Further, genetic variation in CYP19A1 influences both hormone dynamics and outcome post-TBI. PMID:23540392

  3. Randomized, Blinded Trial of Vitamin D3 for Treating Aromatase Inhibitor-Associated Musculoskeletal Symptoms (AIMSS)

    PubMed Central

    Shapiro, Alice C.; Adlis, Susan A.; Robien, Kim; Kirstein, Mark N.; Liang, Shuang; Richter, Sara A.; Lerner, Rachel E.

    2017-01-01

    Purpose To evaluate the efficacy and safety of vitamin D3 at 4,000 IU/day as a treatment option for aromatase inhibitor-associated musculoskeletal symptoms (AIMSS) when compared with the usual care dose of 600 IU D3. Methods Single site randomized, double-blind, phase 3 clinical trial in women with AIMSS comparing change in symptoms, reproductive hormones and AI pharmacokinetics. Postmenopausal women ≥18 years with stage I-IIIA breast cancer, taking AI and experiencing AIMSS (Breast Cancer Prevention Trial Symptom Scale-Musculoskeletal Subscale ≥1.5 (BCPT-MS)) were admitted. Following randomization, 116 patients had a run-in period of 1 month on 600 IU D3, then began the randomized assignment to either 600 IU D3 (n=56) or 4,000 IU D3 (n=57) daily for 6 months. The primary endpoint was change in AIMSS from baseline (after 1 month run-in) on the BCPT-MS (general musculoskeletal pain; joint pain; muscle stiffness; range for each question: 0=not at all to 4=extremely). Results Groups had no statistically significant differences demographically or clinically. There were no discernable differences between the randomly allocated treatment groups at 6 months in measures of AIMSS, pharmacokinetics of anastrozole and letrozole, serum levels of reproductive hormones, or adverse events. Conclusions We found no significant changes in AIMSS measures between women who took 4000 IU D3 daily compared with 600 IU D3. The 4000 IU D3 did not adversely affect reproductive hormone levels or the steady state pharmacokinetics of anastrozole or letrozole. In both groups, serum 25(OH)D remained in the recommended range for bone health (≥30 ng/mL) and safety (<50 ng/mL). PMID:26868123

  4. Aromatase Inhibitor-Associated Bone Fractures: A Case-Cohort GWAS and Functional Genomics

    PubMed Central

    Liu, Mohan; Goss, Paul E.; Ingle, James N.; Kubo, Michiaki; Furukawa, Yoichi; Batzler, Anthony; Jenkins, Gregory D.; Carlson, Erin E.; Nakamura, Yusuke; Schaid, Daniel J.; Chapman, Judy-Anne W.; Shepherd, Lois E.; Ellis, Matthew J.; Khosla, Sundeep; Wang, Liewei

    2014-01-01

    Bone fractures are a major consequence of osteoporosis. There is a direct relationship between serum estrogen concentrations and osteoporosis risk. Aromatase inhibitors (AIs) greatly decrease serum estrogen levels in postmenopausal women, and increased incidence of fractures is a side effect of AI therapy. We performed a discovery case-cohort genome-wide association study (GWAS) using samples from 1071 patients, 231 cases and 840 controls, enrolled in the MA.27 breast cancer AI trial to identify genetic factors involved in AI-related fractures, followed by functional genomic validation. Association analyses identified 20 GWAS single nucleotide polymorphism (SNP) signals with P < 5E-06. After removal of signals in gene deserts and those composed entirely of imputed SNPs, we applied a functional validation “decision cascade” that resulted in validation of the CTSZ-SLMO2-ATP5E, TRAM2-TMEM14A, and MAP4K4 genes. These genes all displayed estradiol (E2)-dependent induction in human fetal osteoblasts transfected with estrogen receptor-α, and their knockdown altered the expression of known osteoporosis-related genes. These same genes also displayed SNP-dependent variation in E2 induction that paralleled the SNP-dependent induction of known osteoporosis genes, such as osteoprotegerin. In summary, our case-cohort GWAS identified SNPs in or near CTSZ-SLMO2-ATP5E, TRAM2-TMEM14A, and MAP4K4 that were associated with risk for bone fracture in estrogen receptor-positive breast cancer patients treated with AIs. These genes displayed E2-dependent induction, their knockdown altered the expression of genes related to osteoporosis, and they displayed SNP genotype-dependent variation in E2 induction. These observations may lead to the identification of novel mechanisms associated with fracture risk in postmenopausal women treated with AIs. PMID:25148458

  5. Randomized Phase II, Double-Blind, Placebo-Controlled Study of Exemestane With or Without Entinostat in Postmenopausal Women With Locally Recurrent or Metastatic Estrogen Receptor-Positive Breast Cancer Progressing on Treatment With a Nonsteroidal Aromatase Inhibitor

    PubMed Central

    Yardley, Denise A.; Ismail-Khan, Roohi R.; Melichar, Bohuslav; Lichinitser, Mikhail; Munster, Pamela N.; Klein, Pamela M.; Cruickshank, Scott; Miller, Kathy D.; Lee, Min J.; Trepel, Jane B

    2013-01-01

    Purpose Entinostat is an oral isoform selective histone deacetylase inhibitor that targets resistance to hormonal therapies in estrogen receptor–positive (ER+) breast cancer. This randomized, placebo-controlled, phase II study evaluated entinostat combined with the aromatase inhibitor exemestane versus exemestane alone. Patients and Methods Postmenopausal women with ER+ advanced breast cancer progressing on a nonsteroidal aromatase inhibitor were randomly assigned to exemestane 25 mg daily plus entinostat 5 mg once per week (EE) or exemestane plus placebo (EP). The primary end point was progression-free survival (PFS). Blood was collected in a subset of patients for evaluation of protein lysine acetylation as a biomarker of entinostat activity. Results One hundred thirty patients were randomly assigned (EE group, n = 64; EP group, n = 66). Based on intent-to-treat analysis, treatment with EE improved median PFS to 4.3 months versus 2.3 months with EP (hazard ratio [HR], 0.73; 95% CI, 0.50 to 1.07; one-sided P = .055; two-sided P = .11 [predefined significance level of .10, one-sided]). Median overall survival was an exploratory end point and improved to 28.1 months with EE versus 19.8 months with EP (HR, 0.59; 95% CI, 0.36 to 0.97; P = .036). Fatigue and neutropenia were the most frequent grade 3/4 toxicities. Treatment discontinuation because of adverse events was higher in the EE group versus the EP group (11% v 2%). Protein lysine hyperacetylation in the EE biomarker subset was associated with prolonged PFS. Conclusion Entinostat added to exemestane is generally well tolerated and demonstrated activity in patients with ER+ advanced breast cancer in this signal-finding phase II study. Acetylation changes may provide an opportunity to maximize clinical benefit with entinostat. Plans for a confirmatory study are underway. PMID:23650416

  6. Aromatase Deficiency due to a Homozygous CYP19A1 Mutation in a 46,XX Egyptian Patient with Ambiguous Genitalia.

    PubMed

    Mazen, Inas; McElreavey, Ken; Elaidy, Aya; Kamel, Alaa K; Abdel-Hamid, Mohamed S

    2017-01-01

    Aromatase deficiency (AD) is a very rare disorder resulting from mutations in the CYP19A1 gene encoding aromatase, a cytochrome P450 enzyme that plays a pivotal role in androgen conversion to estrogens. AD is inherited in an autosomal recessive trait, and to date only 35 cases have been described in the literature. Herein, we depict a new patient reared as a male, who presented at the age of 21 years with no palpable testis, hypoplastic scrotum, penis-like phallus (3 cm), and penoscrotal hypospadias. The patient was born to consanguineous parents, his karyotype was 46,XX, and SRY was negative. Pelvic sonar showed a small hypoplastic uterus, and no testis could be identified. Serum testosterone was within the reference range of females along with high gonadotropins. Pathology of gonadal biopsy showed ovarian stroma negative for oocytic follicle consistent with streak gonads. All these data were suggestive of AD, which was subsequently confirmed by molecular investigation of the CYP19A1 gene. A homozygous splice site mutation in the donor splice site of exon 9 was identified, c.1263 + 1G>T. This is the first report of such a rare disorder in an Egyptian patient. Our results reinforce the importance of considering AD in patients with 46,XX disorders of sex development after ruling out congenital adrenal hyperplasia. © 2018 S. Karger AG, Basel.

  7. Short report: Monitoring ESR1 mutations by circulating tumor DNA in aromatase inhibitor resistant metastatic breast cancer.

    PubMed

    Sefrioui, David; Perdrix, Anne; Sarafan-Vasseur, Nasrin; Dolfus, Claire; Dujon, Antoine; Picquenot, Jean-Michel; Delacour, Julien; Cornic, Marie; Bohers, Elodie; Leheurteur, Marianne; Rigal, Olivier; Tennevet, Isabelle; Thery, Jean-Christophe; Alexandru, Cristina; Guillemet, Cécile; Moldovan, Cristian; Veyret, Corinne; Frebourg, Thierry; Di Fiore, Frédéric; Clatot, Florian

    2015-11-15

    Acquired estrogen receptor gene (ESR1) mutations have been recently reported as a marker of resistance to aromatase inhibitors in hormone receptor positive metastatic breast cancer. We retrospectively considered seven patients treated for metastatic breast cancer with available samples from the primary tumor before any treatment, cryopreserved metastasis removed during progression and concomitant plasmas. All these seven patients were in disease progression after previous exposure to aromatase inhibitors for at least 6 months, and were assessed for ESR1 mutations detection in tumor and circulating DNA. For these patients, Sanger sequencing identified four metastases with clear ESR1 mutation and one possible, whereas digital PCR identified six mutated metastases. Then, under blind conditions and using digital PCR, corresponding circulating ESR1 mutations were successfully detected in four of these six metastatic breast cancer patients. Moreover, in two patients with serial blood samples following treatments exposure, the monitoring of circulating ESR1 mutations clearly predicted disease evolution. In the context of high interest for ESR1 mutations, our results highlight that these acquired recurrent mutations may be tracked in circulating tumor DNA and may be of clinical relevance for metastatic breast cancer patient monitoring. © 2015 UICC.

  8. Inhibition of Aromatase Induces Partial Sex Change in a Cichlid Fish: Distinct Functions for Sex Steroids in Brains and Gonads.

    PubMed

    Göppert, Carolin; Harris, Rayna M; Theis, Anya; Boila, Anna; Hohl, Simon; Rüegg, Attila; Hofmann, Hans A; Salzburger, Walter; Böhne, Astrid

    2016-01-01

    Sex steroids are major drivers of sexual development and also responsible for the maintenance of the established gender. Especially fishes exhibit great plasticity and less conservation in sex determination and sexual development compared to other vertebrate groups. In addition, fishes have a constant sex steroid production throughout their entire lifespan, which makes them particularly susceptible to interferences with the endogenous sex steroid system. This susceptibility has recently been used to show that inhibition of the key enzyme of estrogen synthesis, aromatase Cyp19a1, can induce functional sex reversal even in adult fish. Here, we investigated the impact of the aromatase inhibitor (AI) fadrozole in adult females of the East African cichlid fish Astatotilapia burtoni. Using gene expression, phenotypic measurements, behavioral experiments, and hormone measurements, we assessed if females treated with fadrozole develop a male-like phenotype. We found that AI treatment has a different effect on gene expression in the gonad compared to the brain, the 2 tissues mostly implicated in sexual development. In contrast to observations in other gonochoristic species, A. burtoni ovaries cannot be transformed into functional testis by AI. However, rapid changes towards a male-like phenotype can be induced with AI in coloration, hormone levels, and behavior. © 2016 S. Karger AG, Basel.

  9. Randomized Trial of Aromatase Inhibitors, Growth Hormone, or Combination in Pubertal Boys with Idiopathic, Short Stature

    PubMed Central

    Ross, Judith L.; Gagliardi, Priscila; Yu, Y. Miles; Hossain, Jobayer; Permuy, Joseph; Damaso, Ligeia; Merinbaum, Debbie; Singh, Ravinder J.; Gaete, Ximena; Mericq, Veronica

    2016-01-01

    Context: Growth of short children in puberty is limited by the effect of estrogen on epiphyseal fusion. Objectives: To compare: 1) the efficacy and safety of aromatase inhibitors (AIs) vs GH vs AI/GH on increasing adult height potential in pubertal boys with severe idiopathic short stature (ISS); and 2) differences in body composition among groups. Design: Randomized three-arm open-label comparator. Setting: Outpatient clinical research. Patients: Seventy-six pubertal boys [mean (SE) age, 14.1 (0.1) years] with ISS [height SD score (SDS), −2.3 (0.0)]. Intervention: Daily AIs (anastrozole or letrozole), GH, or AI/GH for 24–36 months. Outcomes: Anthropometry, bone ages, dual x-ray absorptiometry, spine x-rays, hormones, safety labs. Results: Height gain [mean (SE)] at 24 months was: AI, +14.0 (0.8) cm; GH, +17.1 (0.9) cm; AI/GH, +18.9 (0.8) cm (P < .0006, analysis of covariance). Height SDS was: AI, −1.73 (0.12); GH, −1.43 (0.14); AI/GH, −1.25 (0.12) (P < .0012). Those treated through 36 months grew more. Regardless of treatment duration, height SDS at near-final height [n = 71; age, 17.4 (0.2) years; bone age, 15.3 (0.1) years; height achieved, ∼97.6%] was: AI, −1.4 (0.1); GH, −1.4 (0.2); AI/GH, −1.0 (0.1) (P = .06). Absolute height change was: AI, +18.2 (1.6) cm; GH, +20.6 (1.5) cm; AI/GH, +22.5 (1.4) cm (P = .01) (expected height gain at −2.0 height SDS, +13.0 cm). AI/GH had higher fat free mass accrual. Measures of bone health, safety labs, and adverse events were similar in all groups. Letrozole caused higher T and lower estradiol than anastrozole. Conclusions: Combination therapy with AI/GH increases height potential in pubertal boys with ISS more than GH and AI alone treated for 24–36 months with a strong safety profile. PMID:27710241

  10. Effect of aromatase inhibition on bone metabolism in elderly hypogonadal men.

    PubMed

    Leder, Benjamin Z; Finkelstein, Joel S

    2005-12-01

    Both estrogens and androgens play important roles in skeletal development and maintenance in men. The relative importance of estrogens and androgens in male bone metabolism, however, remains undefined. Anastrozole is an oral aromatase inhibitor that decreases estrogen production and increases androgen production in men. Currently, anastrozole is being investigated as a potential agent for the treatment of hypogonadism in aging men. Because anastrozole lowers estrogen levels and raises androgen levels, its effect on bone metabolism is difficult to predict. To assess the effects of anastrozole on bone turnover, we randomized 37 elderly (ages 62-74) mildly hypogonadal men (serum testosterone <350 ng/dl) to receive either anastrozole 1 mg daily (n=12), anastrozole 1 mg twice weekly (n=11), or daily placebo (n=14) for 12 weeks. Serum gonadal steroid levels, serum and urine biochemical markers of bone turnover, serum osteoprotegerin, and total body bone mineral density were measured at baseline and week 12. Mean serum levels of total and bioavailable testosterone increased substantially in both treated groups. Specifically, mean +/- SD bioavailable testosterone levels increased from 99+/-31 ng/dl to 207+/-65 ng/dl in the group receiving 1 mg of anastrozole daily and from 115+/-37 ng/dl to 178+/-55 ng/dl in the subjects receiving 1 mg of anastrozole twice weekly ( p <0.001 vs placebo for both groups). Serum estradiol levels decreased modestly in both treated groups (from 26+/-8 pg/ml to 17+/-6 pg/ml in the daily treatment group and from 27+/-8 pg/ml to 17+/-5 pg/ml in the twice-weekly treatment group, p <0.001 vs placebo for both groups). Despite these hormonal changes, no increases in biochemical markers of bone resorption were observed. Specifically, mean serum N-telopeptide and urinary deoxypyridinoline concentrations remained stable in both treated groups over the 12-week treatment period. Similarly, serum biochemical markers of bone formation (osteocalcin and amino

  11. Aromatase inhibitors decrease radiation-induced lung fibrosis: Results of an experimental study.

    PubMed

    Altinok, A Y; Yildirim, S; Altug, T; Sut, N; Ober, A; Ozsahin, E M; Azria, D; Bese, N S

    2016-08-01

    In experimental and clinical trials, tamoxifen (TAM) has been shown to increase radiation-induced lung fibrosis (RILF). Furthermore, aromatase inhibitors (AI) have been shown to be superior to TAM in the adjuvant setting and preclinical data suggest that letrozole (LET) sensitizes breast cancer cells to ionizing radiation in other studies. In this experimental study, we evaluated whether AI have any impact on the development of RILF in rats. 60 female wistar- albino rats were divided into 6 groups: Control (group A), RT alone (group B), RT + TAM (group C), RT + anastrozole (ANA group D), RT + LET (group E), and RT + exemestane (EXE, group F). RT consisted of 30 Gy in 10 fractions to both lungs with an anterior field at 2 cm depth. Equivalent doses for 60 kg adult dose per day of TAM, ANA, LET, and EXE were calculated according to the mean weight of rats and orally administrated with a feeding tube. Percentage of lung with fibrosis was quantified with image analysis of histological sections of the lung. The mean score values were calculated for each group. the significance of the differences among groups were calculated using one way ANOVA test and Tukey HSD post-hoc test. Mean values of fibrosis were 1.7, 5.9, 6.7, 2.5, 2 and 2.2 for groups A, B, C, D, E, and F, respectively (p = 0.000). TAM increased RT-induced lung fibrosis but without statistical significance. Groups treated with RT + AI showed significantly less lung fibrosis than groups treated with RT alone or RT + TAM (p = 0.000). RT + AI groups showed nearly similar RT-induced lung fibrosis than control group. In this study, we found that AI decreased RT-induced lung fibrosis to the control group level suggesting protective effect. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Randomized Trial of Aromatase Inhibitors, Growth Hormone, or Combination in Pubertal Boys with Idiopathic, Short Stature.

    PubMed

    Mauras, Nelly; Ross, Judith L; Gagliardi, Priscila; Yu, Y Miles; Hossain, Jobayer; Permuy, Joseph; Damaso, Ligeia; Merinbaum, Debbie; Singh, Ravinder J; Gaete, Ximena; Mericq, Veronica

    2016-12-01

    Growth of short children in puberty is limited by the effect of estrogen on epiphyseal fusion. To compare: 1) the efficacy and safety of aromatase inhibitors (AIs) vs GH vs AI/GH on increasing adult height potential in pubertal boys with severe idiopathic short stature (ISS); and 2) differences in body composition among groups. Randomized three-arm open-label comparator. Outpatient clinical research. Seventy-six pubertal boys [mean (SE) age, 14.1 (0.1) years] with ISS [height SD score (SDS), -2.3 (0.0)]. Daily AIs (anastrozole or letrozole), GH, or AI/GH for 24-36 months. Anthropometry, bone ages, dual x-ray absorptiometry, spine x-rays, hormones, safety labs. Height gain [mean (SE)] at 24 months was: AI, +14.0 (0.8) cm; GH, +17.1 (0.9) cm; AI/GH, +18.9 (0.8) cm (P < .0006, analysis of covariance). Height SDS was: AI, -1.73 (0.12); GH, -1.43 (0.14); AI/GH, -1.25 (0.12) (P < .0012). Those treated through 36 months grew more. Regardless of treatment duration, height SDS at near-final height [n = 71; age, 17.4 (0.2) years; bone age, 15.3 (0.1) years; height achieved, ∼97.6%] was: AI, -1.4 (0.1); GH, -1.4 (0.2); AI/GH, -1.0 (0.1) (P = .06). Absolute height change was: AI, +18.2 (1.6) cm; GH, +20.6 (1.5) cm; AI/GH, +22.5 (1.4) cm (P = .01) (expected height gain at -2.0 height SDS, +13.0 cm). AI/GH had higher fat free mass accrual. Measures of bone health, safety labs, and adverse events were similar in all groups. Letrozole caused higher T and lower estradiol than anastrozole. Combination therapy with AI/GH increases height potential in pubertal boys with ISS more than GH and AI alone treated for 24-36 months with a strong safety profile.

  13. A randomized, controlled clinical trial comparing the effects of aromatase inhibitor (letrozole) and gonadotropin-releasing hormone agonist (triptorelin) on uterine leiomyoma volume and hormonal status.

    PubMed

    Parsanezhad, Mohammad Ebrahim; Azmoon, Mina; Alborzi, Saeed; Rajaeefard, Abdoreza; Zarei, Afsun; Kazerooni, Talieh; Frank, Vivian; Schmidt, Ernst Hienrich

    2010-01-01

    To examine and compare the efficacy and safety of GnRH agonist (GnRHa) vs. aromatase inhibitor in premenopausal women with leiomyomas. Multicenter, randomized, controlled clinical trial. University hospitals. A total of 70 subjects with a single uterine myoma measuring >or=5 cm. Subjects were randomized into two groups with use of a random table. They were treated with aromatase inhibitor (group A) or GnRHa (group B). Group A received letrozole (2.5 mg/d) for 12 weeks. Group B received triptorelin (3.75 mg/mo) for 12 weeks. Measurement of myoma volume and E(2), FSH, LH, and T levels. Total myoma volume decreased by 45.6% in group A and 33.2% in group B. Reductions in myoma volume in the two groups were statistically significant. There was no significant change in hormonal milieu in group A. The serum level of hormones significantly decreased in group B by the 12th week of treatment. Uterine myoma volume was successfully reduced by use of an aromatase inhibitor. Rapid onset of action and avoidance of initial gonadotropin flare with an aromatase inhibitor may be advantageous for short-term management of women with myomas of any size who are to be managed transiently and who wish to avoid surgical intervention, specifically women with unexplained infertility having uterine myoma. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. Distribution of aromatase and sex steroid receptors in the baculum during the rat life cycle: effects of estrogen during the early development of the baculum.

    PubMed

    Yonezawa, Tomohiro; Higashi, Mayuko; Yoshioka, Kazuki; Mutoh, Ken-ichiro

    2011-07-01

    The baculum, also called os penis, plays an important role during copulation. However, the hormonal regulation of its development remains to be elucidated. To determine the direct involvement of sex steroids in the development of the baculum of rats, the distributions of androgen receptors (ARs), aromatase, and estrogen receptor alpha (ESR1) were observed immunohistochemically. On Postnatal Day 1, the rudiment of the baculum expressed ARs, aromatase, and ESR1. In the proximal segment of the baculum of neonatal rats, ARs were expressed in the parosteal layer but not in the periosteum or osteoblasts. Aromatase was expressed from the parosteal layer to the endosteum, particularly in the inner osteogenic layer. ESR1 was also abundantly expressed in almost all cells from the parosteal layer to the endosteum. ARs, aromatase, and ESR1 were all abundantly expressed during the neonatal period in the hyaline cartilage of the proximal segment and in fibrocartilage of the distal segment of the baculum. Expression in all the tissues was attenuated in an age-dependent manner and became quite weak at puberty. To determine the effect of estrogen on the growth of the baculum, the aromatase inhibitor 1,4,6-androstatrien-3,17-dione (ATD) was subcutaneously injected daily into pregnant rats from Days 19 to 23 of gestation and into pups on postnatal Days 1, 3, 5, 7, and 9. On Day 10, the length of the baculum in the ATD-treated rats was significantly shorter than that in the controls, although the body weight did not change. These findings suggest that not only androgen but also locally aromatized estrogen is involved in the early growth and development of the baculum.

  15. Anti-colon cancer activity of Murraya koenigii leaves is due to constituent murrayazoline and O-methylmurrayamine A induced mTOR/AKT downregulation and mitochondrial apoptosis.

    PubMed

    Arun, Ashutosh; Patel, Om P S; Saini, Deepika; Yadav, Prem P; Konwar, Rituraj

    2017-09-01

    In recent years, many alkaloids of plant origin have attracted great attention due to their diverse range of biological properties including anti-hyperglycemic, anti-oxidant, anti-inflammatory, anti-diabetic and anti-tumor activity. Herein, the pyranocarbazole alkaloids were isolated from leaves of Murraya koenigii and their anti-cancer potential was investigated in different cancer cell lines. Among all tested compounds, murrayazoline and O-methylmurrayamine A demonstrated potent anti-cancer activity against DLD-1 colon cancer cells with the IC 50 values of 5.7μM and 17.9μM, respectively, without any non-specific cytotoxicity against non-cancer HEK-293 and HaCaT cells. Further, studies of pure compounds revealed that the anti-cancer activity of compounds corresponds with altered cellular morphology, cell cycle arrest in G2/M phase, reactive oxygen species level and mitochondrial membrane depolarization of colon cancer cells. In addition, these compounds activated caspase-3 protein and upregulated Bax/Bcl-2 protein expression ratio leading to induction of caspase-dependent apoptosis in DLD-1 cells. These event induced by carbazole alkaloids also coincides with downregulation of Akt/mTOR suggesting downstream targeting of cell survival pathway. Thus, our in vitro studies not only provided scientific basis of the use of M. koenigii leaves in the traditional Indian Ayurveda medicines, but also expands possibilities of medicinal uses of M. koenigii leaves against colon cancer. Particularly, these findings will help in further investigating murrayazoline and O-methylmurrayamine A or their improvised derivatives as new therapeutics for the treatment of colon cancer. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. Altered gene expression in the brain and ovaries of zebrafish (Danio rerio) exposed to the aromatase inhibitor fadrozole: microarray analysis and hypothesis generation.

    PubMed

    Villeneuve, L; Wang, Rong-Lin; Bencic, David C; Biales, Adam D; Martinović, Dalma; Lazorchak, James M; Toth, Gregory; Ankley, Gerald T

    2009-08-01

    As part of a research effort examining system-wide responses of the hypothalamic-pituitary-gonadal (HPG) axis in fish to endocrine-active chemicals (EACs) with different modes of action, zebrafish (Danio rerio) were exposed to 25 or 100 microg/L of the aromatase inhibitor fadrozole for 24, 48, or 96 h. Global transcriptional response in brain and ovarian tissue of fish exposed to 25 microg/L of fadrozole was compared to that in control fish using a commercially available, 22,000-gene oligonucleotide microarray. Transcripts altered in brain were functionally linked to differentiation, development, DNA replication, and cell cycle. Additionally, multiple genes associated with the one-carbon pool by folate pathway (KEGG 00670) were significantly up-regulated. Transcripts altered in ovary were functionally linked to cell-cell adhesion, extracellular matrix, vasculogenesis, and development. Promoter motif analysis identified GATA-binding factor 2, Ikaros 2, alcohol dehydrogenase gene regulator 1, myoblast-determining factor, and several heat shock factors as being associated with coexpressed gene clusters that were differentially expressed following exposure to fadrozole. Based on the transcriptional changes observed, it was hypothesized that fadrozole elicits neurodegenerative stress in brain tissue and that fish cope with this stress through proliferation of radial glial cells. Additionally, it was hypothesized that changes of gene expression in the ovary of fadrozole-exposed zebrafish reflect disruption of oocyte maturation and ovulation because of impaired vitellogenesis. These hypotheses and others derived from the microarray results provide a foundation for future studies aimed at understanding responses of the HPG axis to EACs and other chemical stressors.

  17. Activation of Autophagic Flux against Xenoestrogen Bisphenol-A-induced Hippocampal Neurodegeneration via AMP kinase (AMPK)/Mammalian Target of Rapamycin (mTOR) Pathways*

    PubMed Central

    Agarwal, Swati; Tiwari, Shashi Kant; Seth, Brashket; Yadav, Anuradha; Singh, Anshuman; Mudawal, Anubha; Chauhan, Lalit Kumar Singh; Gupta, Shailendra Kumar; Choubey, Vinay; Tripathi, Anurag; Kumar, Amit; Ray, Ratan Singh; Shukla, Shubha; Parmar, Devendra; Chaturvedi, Rajnish Kumar

    2015-01-01

    The human health hazards related to persisting use of bisphenol-A (BPA) are well documented. BPA-induced neurotoxicity occurs with the generation of oxidative stress, neurodegeneration, and cognitive dysfunctions. However, the cellular and molecular mechanism(s) of the effects of BPA on autophagy and association with oxidative stress and apoptosis are still elusive. We observed that BPA exposure during the early postnatal period enhanced the expression and the levels of autophagy genes/proteins. BPA treatment in the presence of bafilomycin A1 increased the levels of LC3-II and SQSTM1 and also potentiated GFP-LC3 puncta index in GFP-LC3-transfected hippocampal neural stem cell-derived neurons. BPA-induced generation of reactive oxygen species and apoptosis were mitigated by a pharmacological activator of autophagy (rapamycin). Pharmacological (wortmannin and bafilomycin A1) and genetic (beclin siRNA) inhibition of autophagy aggravated BPA neurotoxicity. Activation of autophagy against BPA resulted in intracellular energy sensor AMP kinase (AMPK) activation, increased phosphorylation of raptor and acetyl-CoA carboxylase, and decreased phosphorylation of ULK1 (Ser-757), and silencing of AMPK exacerbated BPA neurotoxicity. Conversely, BPA exposure down-regulated the mammalian target of rapamycin (mTOR) pathway by phosphorylation of raptor as a transient cell's compensatory mechanism to preserve cellular energy pool. Moreover, silencing of mTOR enhanced autophagy, which further alleviated BPA-induced reactive oxygen species generation and apoptosis. BPA-mediated neurotoxicity also resulted in mitochondrial loss, bioenergetic deficits, and increased PARKIN mitochondrial translocation, suggesting enhanced mitophagy. These results suggest implication of autophagy against BPA-mediated neurodegeneration through involvement of AMPK and mTOR pathways. Hence, autophagy, which arbitrates cell survival and demise during stress conditions, requires further assessment to be

  18. WITHAFERIN A INDUCES APOPTOSIS IN RAT C6 GLIOMA CELLS THROUGH REGULATING NF-KB NUCLEAR TRANSLOCATION AND ACTIVATION OF CASPASE CASCADE.

    PubMed

    Hou, Wei-Chen; Miao, Xiao-Hui; Ma, Lian-Jun; Bai, Xiao-Xue; Liu, Qun; Song, Lei

    2017-01-01

    The demand for the chemopreventive drug from the plant source is increasing in recent times, owing to its various biological activities without any adverse effect. The intention of this current study was to examine the anti-glioma effect of Withaferin A (WFA) on C6 glioma cell line model. C6 glioma cells were administrated with different concentration of WFA (50, 100, 200 and 500 μg/mL) and DMSO (control) group to examine its anti-proliferative, anti-inflammatory and pro-apoptotic activities. Treatment with WFA showed a significant decline in the glioma cell count in a dose-dependent manner and thus proving its anti-proliferative effect. Similarly, inflammatory markers were also substantially lowered upon treatment with different concentration of WFA. However, DNA fragmentation and apoptotic markers like Caspase-3 and 9 were concomitantly enhanced after co-cultured with different concentration of WFA and thus exhibiting its cytotoxicity efficacy. Furthermore, the protein expression of Bcl2 and Bax were markedly downregulated and upregulated respectively; upon treatment with WFA on C6 glioma cells. The outcome of this study evidently demonstrates that C6 glioma cells co-cultured with increased concentration of WFA, showed an anti-proliferative, anti-inflammatory and pro-apoptotic effect in a dose-dependent fashion.

  19. Inhibition of C5a-induced inflammation with preserved C5b-9-mediated bactericidal activity in a human whole blood model of meningococcal sepsis.

    PubMed

    Sprong, Tom; Brandtzaeg, Petter; Fung, Michael; Pharo, Anne M; Høiby, E Arne; Michaelsen, Terje E; Aase, Audun; van der Meer, Jos W M; van Deuren, Marcel; Mollnes, Tom E

    2003-11-15

    The complement system plays an important role in the initial defense against Neisseria meningitidis. In contrast, uncontrolled activation in meningococcal sepsis contributes to the development of tissue damage and shock. In a novel human whole blood model of meningococcal sepsis, we studied the effect of complement inhibition on inflammation and bacterial killing. Monoclonal antibodies (mAbs) blocking lectin and alternative pathways inhibited complement activation by N meningitidis and oxidative burst induced in granulocytes and monocytes. Oxidative burst was critically dependent on CD11b/CD18 (CR3) expression but not on Fc gamma-receptors. Specific inhibition of C5a using mAb 137-26 binding the C5a moiety of C5 before cleavage prohibited CR3 up-regulation, phagocytosis, and oxidative burst but had no effect on C5b-9 (TCC) formation, lysis, and bacterial killing. An mAb-blocking cleavage of C5, preventing C5a and TCC formation, showed the same effect on CR3, phagocytosis, and oxidative burst as the anti-C5a mAb but additionally inhibited TCC formation, lysis, and bacterial killing, consistent with a C5b-9-dependent killing mechanism. In conclusion, the anti-C5a mAb 137-26 inhibits the potentially harmful effects of N meningitidis-induced C5a formation while preserving complement-mediated bacterial killing. We suggest that this may be an attractive approach for the treatment of meningococcal sepsis.

  20. Maternal Methyl Donor Supplementation during Gestation Counteracts the Bisphenol A-Induced Impairment of Intestinal Morphology, Disaccharidase Activity, and Nutrient Transporters Gene Expression in Newborn and Weaning Pigs

    PubMed Central

    Liu, Hong; Wang, Jun; Mou, Daolin; Che, Lianqiang; Fang, Zhengfeng; Feng, Bin; Lin, Yan; Xu, Shengyu; Li, Jian; Wu, De

    2017-01-01

    This study was conducted to explore whether exposure to bisphenol A (BPA) during pregnancy could change intestinal digestion and absorption function in offspring using pigs as a model, and whether methyl donor (MET) could counteract the BPA-induced impacts. Fifty Landrace × Yorkshire sows were divided into four dietary groups throughout gestation: control diet (CON); control diet supplemented with BPA (50 mg/kg); control diet supplemented with MET (3 g/kg betaine, 400 mg/kg choline, 150 μg/kg vitamin B12, and 15 mg/kg folic acid); and control diet with BPA and MET supplementation (BPA + MET). Intestine samples were collected from pigs’ offspring at birth and weaning. Maternal BPA exposure during pregnancy significantly reduced the ratio of jejunum villus height to crypt depth, decreased the jejunum sucrase activity, down-regulated the mRNA expression of jejunum peptide transporter 1 (Pept1) and DNA methyl transferase 3a (DNMT3a), and decreased the DNA methylation level of jejunum Pept1 in offspring (p < 0.05). Maternal MET supplementation significantly raised the ratio of villus height to crypt depth in jejunum and ileum, improved the jejunum lactase activity, up-regulated the mRNA expression of jejunum Pept1, lactase (LCT), DNMT1, DNMT3a, and methylenetetrahydrofolate reductase (MTHFR), and increased the DNA methylation level of jejunum Pept1 in offspring (p < 0.05). However, the ratio of jejunum villus height to crypt depth was higher in BPA + MET treatment compared with CON and BPA treatment (p < 0.05). Meanwhile, there was no difference in the jejunum sucrase activity, the mRNA expression of jejunum Pept1 and DNMT3a, and the DNA methylation level of jejunum Pept1 between CON and BPA + MET treatment. These results indicated that maternal exposure to BPA during gestation might suppress offspring’s intestinal digestion and absorption function, whereas supplementation of MET could counteract these damages, which might be associated with DNA methylation. PMID

  1. IgA Enhances IGF-1 Mitogenic Activity Via Receptor Modulation in Glomerular Mesangial Cells: Implications for IgA-Induced Nephropathy.

    PubMed

    Al-Eisa, Amal; Dhaunsi, Gursev S

    2017-01-01

    Glomerulonephritis due to mesangial proliferation is responsible for renal dysfunction in IgA nephropathy (IgAN), however molecular mechanisms of pathogenesis are not well known. We examined the effect of IgA on Insulin-like Growth Factor-1 (IGF-1) activity, a potent mitogen with vital role in growth and development of children, and IGF-1 receptor (IGF-1R) in cultures of glomerular mesangial cells (GMC). GMC were isolated from rat kidneys using sieving and enzymatic digestion of tissue homogenates, and cultured in RPMI 1640 medium. GMC cultures were treated with IgA (0-10 µg/ml) in the presence or absence of IGF-1 and fetal bovine serum (FBS), and BrdU incorporation was measured. IGF-1 levels were assayed along with real-time PCR quantification of IGF-1R mRNA. Treatment of GMC with IgA (5 -10 µg/ml) significantly (p < 0.01) increased the BrdU incorporation in the presence or absence of FBS or IGF-1. IgA-mediated effects were more pronounced in IGF-1 treated cells that were significantly (p < 0.01) blocked by pretreatment of cells with IGF-1 receptor antibody or genistein. IgA significantly increased the levels of IGF-1 in culture supernatants and GMC homogenates. IGF-1R mRNA was significantly (p < 0.01) increased in IgA treated cells particularly by co-treatment with IGF-1. These findings show that IgA enhances the IGF-1 activity in GMC via stimulation of IGF-1R gene transcription and suggest a role for IGF-1 in pathogenesis of IgAN. © 2017 The Author(s). Published by S. Karger AG, Basel.

  2. Prospective endometrial assessment of breast cancer patients treated with third generation aromatase inhibitors.

    PubMed

    Garuti, Giancarlo; Cellani, Fulvia; Centinaio, Giovanna; Montanari, Giuseppe; Nalli, Giulio; Luerti, Massimo

    2006-11-01

    A prospective evaluation of the effects on endometrium of third generation aromatase inhibitors (AIs), administered as adjuvant up-front therapy or switched therapy in menopausal patients suffering from breast cancer. Forty-five patients suffering from estrogen-receptor positive breast cancer were treated with AIs as adjuvant endocrine therapy; 27 patients switched from tamoxifen to AIs (group 1) due to adverse medical events related to tamoxifen intake (22 patients) or to an extended endocrine treatment after 60 months of tamoxifen therapy (5 patients); whereas 18 patients received AIs as up-front adjuvant therapy (group 2). All patients underwent endometrial investigation before the start of AIs therapy and, thereafter, at 12 month intervals. Endometrial assessment was based on Transvaginal Ultrasonography (TU), followed by hysteroscopy and endometrial biopsy when a double layered endometrial stripe above 4 mm was measured on the longitudinal plane of uterine scanning. Six patients, showing endometrial hyperplasia before the start of AIs therapy, underwent hysteroscopy on a yearly basis, disregarding the endometrial thickness measured by TU. Histopathologic results on endometrial biopsies represented the reference test in order to estimate the prevalence of endometrial morbidity. Demographic and clinical variables evaluated (age, parity, age at menarche and menopause, Body Mass Index, previous chemotherapy and radiotherapy) did not differ in groups 1 and 2. The average period of endometrial surveillance after the start of AIs therapy was 24.8 +/-10.8 months for group 1 and 21.4 +/- 11.5 months for group 2. A progressive decrease of endometrial thickness, from 8.2 +/- 5.0 to 3.0 +/- 1.2 in group 1 and from 4.7 +/- 4.3 to 1.9 +/- 0.3 in group 2, was found before the start and after 36-48 months of AIs therapy. The second line endometrial investigations' rate dropped from 70.3% to 12.5% in group 1 and from 27.7% to 0.0% in group 2, at baseline and after 36-48 months

  3. Aromatase inhibitor letrozole downregulates steroid receptor coactivator-1 in specific brain regions that primarily related to memory, neuroendocrine and integration.

    PubMed

    Bian, Chen; Zhao, Yangang; Guo, Qiang; Xiong, Ying; Cai, Wenqin; Zhang, Jiqiang

    2014-05-01

    As one of the third generation of aromatase inhibitors, letrozole is a favored drug for the treatment of hormone receptor-positive breast cancer with some adverse effects on the nervous system, but the knowledge is limited and the results are controversial, the mechanism underlying its central action is also unclear. Accumulated evidences have demonstrated that estrogens derived from androgens by aromatase play profound roles in the brain through their receptors, which needs coactivator for the transcription regulation, among which steroid receptor coactivator-1 (SRC-1) has been shown to be multifunctional potentials in the brain, but whether it is regulated by letrozole is currently unknown. In this study, we examined letrozole regulation on SRC-1 expression in adult mice brain using immunohistochemistry. The results showed that letrozole induced dramatic decrease of SRC-1 in the medial septal, hippocampus, medial habenular nucleus, arcuate hypothalamic nucleus and superior colliculus (p<0.01). Significant decrease was detected in the dorsal lateral septal nucleus, bed nucleus of stria terminalis, ventral taenia tecta, dorsomedial and ventromedial hypothalamic nuclei, dorsomedial periaqueductal gray, superior paraolivary nucleus and pontine nucleus (p<0.05). In the hippocampus, levels of estradiol content, androgen receptor, estrogen receptor α and β also decreased significantly after letrozole injection. The above results demonstrated letrozole downregulation of SRC-1 in specific regions that are primarily related to learning and memory, cognition and mood, neuroendocrine as well as information integration, indicating that SRC-1 may be one important downstream central target of letrozole. Furthermore, these potential central adverse effects of letrozole should be taken into serious considerations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Use of Aromatase Inhibitors in Large Cell Calcifying Sertoli Cell Tumors: Effects on Gynecomastia, Growth Velocity, and Bone Age

    PubMed Central

    Crocker, Melissa K.; Gourgari, Evgenia; Stratakis, Constantine A.

    2014-01-01

    Context: Large cell calcifying Sertoli cell tumors (LCCSCT) present in isolation or, especially in children, in association with Carney Complex (CNC) or Peutz-Jeghers Syndrome (PJS). These tumors overexpress aromatase (CYP19A1), which leads to increased conversion of delta-4-androstenedione to estrone and testosterone to estradiol. Prepubertal boys may present with growth acceleration, advanced bone age, and gynecomastia. Objective: To investigate the outcomes of aromatase inhibitor therapy (AIT) in prepubertal boys with LCCSCTs. Design: Case series of a very rare tumor and chart review of cases treated at other institutions. Setting: Tertiary care and referral center. Patients: Six boys, five with PJS and one with CNC, were referred to the National Institutes of Health for treatment of LCCSCT. All patients had gynecomastia, testicular enlargement, and advanced bone ages, and were being treated by their referring physicians with AIT. Interventions: Patients were treated for a total of 6–60 months on AIT. Main Outcome Measures: Height, breast tissue mass, and testicular size were all followed; physical examination, scrotal ultrasounds, and bone ages were obtained, and hormonal concentrations and tumor markers were measured. Results: Tumor markers were negative. All patients had decreases in breast tissue while on therapy. Height percentiles declined, and predicted adult height moved closer to midparental height as bone age advancement slowed. Testicular enlargement stabilized until entry into central puberty. Only one patient required unilateral orchiectomy. Conclusions: Patients with LCCSCT benefit from AIT with reduction and/or elimination of gynecomastia and slowing of linear growth and bone age advancement. Further study of long-term outcomes and safety monitoring are needed but these preliminary data suggest that mammoplasty and/or orchiectomy may be foregone in light of the availability of medical therapy. PMID:25226294

  5. Comparison of pharmacokinetics of newly discovered aromatase inhibitors by a cassette microdosing approach in healthy Japanese subjects.

    PubMed

    Kusuhara, Hiroyuki; Takashima, Tadayuki; Fujii, Hisako; Takashima, Tsutomu; Tanaka, Masaaki; Ishii, Akira; Tazawa, Shusaku; Takahashi, Kazuhiro; Takahashi, Kayo; Tokai, Hidekichi; Yano, Tsuneo; Kataoka, Makoto; Inano, Akihiro; Yoshida, Suguru; Hosoya, Takamitsu; Sugiyama, Yuichi; Yamashita, Shinji; Hojo, Taisuke; Watanabe, Yasuyoshi

    2017-12-01

    The aim of the present study is to investigate the pharmacokinetics of our newly developed aromatase inhibitors (cetrozole and TMD-322) in healthy subjects by a cassette microdose strategy. A cocktail of cetrozole and TMD-322 was administered intravenously or orally (1.98 μg for each drug) to six healthy volunteers in a crossover fashion. Anastrozole (1.98 μg) was also included in the oral cocktail. Total body clearance and bioavailability were 12.1 ± 7.1 mL/min/kg and 34.9 ± 32.3% for cetrozole, and 16.8 ± 3.5 mL/min/kg and 18.4 ± 12.2% for TMD-322, respectively. The area under the plasma concentration-time curves of cetrozole and TMD-322 after oral administration was markedly lower than that of anastrozole because of their high hepatic clearance. Two subjects out of six exhibited 4- and 17-fold larger exposure of cetrozole than the others following intravenous and oral administration, respectively. Such variation was not observed for TMD-322 and anastrozole. Extensive metabolism of cetrozole and TMD-322 was observed in the CYP2C19 expression system among the test CYP isoforms (CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4). We report the first clinical investigation of our aromatase inhibitors by a cassette microdose strategy in healthy Japanese subjects. This strategy offers an optional approach for candidate selection as a phase zero study in drug development. Copyright © 2017. Published by Elsevier Ltd.

  6. Lipopolysaccharides-stimulated macrophage products enhance Withaferin A-induced apoptosis via activation of caspases and inhibition of NF-κB pathway in human cancer cells.

    PubMed

    Piao, Liang; Canguo, Zhao; Wenjie, Lu; Xiaoli, Cheng; Wenli, Shi; Li, Lu

    2017-01-01

    Macrophages, as a major cellular component in tumor microenvironment, play an important role in tumor progression. However, their roles in modulation of cytotoxic chemotherapy are still not fully understood. Here, we investigated the influence of Lipoplysaccharides (LPS)-stimulated macrophage products (LSMP) on Withaferin A (WA), a natural compound that derived from the medicinal plant Withania somnifera, as an antitumor agent in human breast cancer cells MDA-MB-231 and prostate cancer cells PC-3. Our results revealed that LSMP may enhance WA-induced apoptosis in both cell lines, the underlying mechanisms of which are closely associated with activation of caspase-8, -9 and -3, cleavage of poly ADP-ribose polymerase (PARP), as well as specifically inhibiting the translocation of nuclear factor-κB (NF-κB) and down-regulation of anti-apoptotic proteins X-linked inhibitor of apoptosis protein (XIAP) and inhibitor of apoptosis protein (cIAP1/2). These findings demonstrate that macrophages in tumor microenvironment can modulate tumor responses to chemotoxic agents, providing an effective strategy that targets macrophages to enhance the antitumor efficacy of cytotoxic chemotherapy. Copyright © 2016. Published by Elsevier Ltd.

  7. Inhibition of estrogen biosynthesis with a potent aromatase inhibitor increases predicted adult height in boys with idiopathic short stature: a randomized controlled trial.

    PubMed

    Hero, Matti; Norjavaara, Ensio; Dunkel, Leo

    2005-12-01

    In males as well as in females, estrogen is an essential regulator of bone maturation, growth plate fusion, and cessation of longitudinal growth. Therefore, an increase in predicted adult height (PAH) may be achieved in short boys by blocking estrogen biosynthesis. We tested the hypothesis that a decrease in the rate of bone maturation and an increase in PAH can be achieved in boys with idiopathic short stature (ISS) by the method of blocking estrogen biosynthesis with an aromatase inhibitor. Secondarily, we investigated the effects of aromatase inhibition on bone mineralization. This was a prospective, double-blind, randomized, placebo (Pl)-controlled clinical study. The study was performed at a university hospital out-patient clinic. Thirty-one boys, aged 9.0-14.5 yr, with ISS were studied. The boys were treated with the aromatase inhibitor letrozole (Lz; 2.5 mg/d) or Pl for 2 yr. The main outcome measure was the change in PAH after 24 months of treatment. PAH increased by 5.9 cm (P < 0.0001), and height SD score for bone age increased by 0.7 SD score (P < 0.0001) in the Lz-treated boys, whereas no changes occurred in the respective measures in Pl-treated boys. Areal bone mineral density of the lumbar spine and femoral neck, assessed by dual-energy x-ray absorptiometry, increased in a similar fashion in both groups during the treatment, whereas bone mineral apparent density increased only in those taking Lz (median increase, 4.3%; P = 0.009). Treatment with the aromatase inhibitor Lz delays bone maturation and improves PAH in boys with ISS. No adverse effects on bone mineralization were evident after 2 yr of treatment.

  8. Localization and Divergent Profiles of Estrogen Receptors and Aromatase in the Vocal and Auditory Networks of a Fish with Alternative Mating Tactics

    PubMed Central

    Fergus, Daniel J.; Bass, Andrew H.

    2013-01-01

    Estrogens play a salient role in the development and maintenance of both male and female nervous systems and behaviors. The plainfin midshipman (Porichthys notatus), a teleost fish, has two male reproductive morphs that follow alternative mating tactics and diverge in multiple somatic, hormonal and neural traits, including the central control of morph-specific vocal behaviors. After we identified duplicate estrogen receptors (ERβ1 and ERβ2) in midshipman, we developed antibodies to localize protein expression in the central vocal-acoustic networks and saccule, the auditory division of the inner ear. As in other teleost species, ERβ1 and ERβ2 were robustly expressed in the telencephalon and hypothalamus in vocal-acoustic and other brain regions shown previously to exhibit strong expression of ERα and aromatase (estrogen synthetase, CYP19) in midshipman. Like aromatase, ERβ1 label co-localized with glial fibrillary acidic protein (GFAP) in telencephalic radial glial cells. Quantitative PCR revealed similar patterns of transcript abundance across reproductive morphs for ERβ1, ERβ2, ERα and aromatase in the forebrain and saccule. In contrast, transcript abundance for ERs and aromatase varied significantly between morphs in and around the sexually polymorphic vocal motor nucleus (VMN). Together, the results suggest that VMN is the major estrogen target within the estrogen-sensitive hindbrain vocal network that directly determines the duration, frequency and amplitude of morph-specific vocalizations. Comparable regional differences in steroid receptor abundances likely regulate morph-specific behaviors in males and females of other species exhibiting alternative reproductive tactics. PMID:23460422

  9. A syndrome of female pseudohermaphrodism, hypergonadotropic hypogonadism, and multicystic ovaries associated with missense mutations in the gene encoding aromatase (P450arom)

    SciTech Connect

    Conte, F.A.; Grumbach, M.M.; Ito, Y.

    The authors report the features of a new syndrome of aromatase deficiency due to molecular defects in the CYP19 (P450arom) gene in a 46,XX female. At birth, the patient presented with a nonadrenal form of female pseudohermaphrodism. At 17 months of age, laparotomy revealed normal female internal genital structures; the histological appearance of the ovaries was normal. FSH concentrations were markedly elevated at 9.4 ng/mL LER 869, and estrone and estradiol levels were undetectable (<37 pmol/L). By 14 yr of age, she had failed to exhibit breast development. The clitoris has enlarged to 4 x 2 cm, and pubic hairmore » was Tanner stage IV. The plasma concentration of testosterone was elevated at 3294 pmol/L, as was androstenedione at 9951 pmol/L. Plasma estradiol levels were below 37 pmol/L. ACTH and dexamethasone tests indicated a nonadrenal source of testosterone and androstenedione. Plasma gonadotropin levels were in the castrate range. Pelvic sonography and magnetic resonance imaging showed multiple 4- to 6-cm ovarian cysts bilaterally. Despite increased circulating androgens and clitoral growth, the bone age was 10 yr at chronologic age 14 2/12 yr. Estrogen replacement therapy resulted in a growth spurt, breast development, menarche, suppression of gonadotropin levels, and resolution of the cysts. The clinical findings suggested the diagnosis of P450arom deficiency. Analyses of genomic DNA from ovarian fibroblasts demonstrated two single base changes in the coding region of the P450arom gene, one at 1303 basepairs (C-T), R435C, and the other at 1310 basepairs (G-A), C437Y, in exon 10. The molecular genetic studies indicate that the patient is a compound heterozygote for these mutations. Expression of these mutations showed that the R435C mutation had 1.1% the activity of the wild-type P450arom enzyme, whereas the C437Y mutation demonstrated no activity. 32 refs., 6 figs., 2 tabs.« less

  10. Magnolol Attenuates Concanavalin A-induced Hepatic Fibrosis, Inhibits CD4+ T Helper 17 (Th17) Cell Differentiation and Suppresses Hepatic Stellate Cell Activation: Blockade of Smad3/Smad4 Signalling.

    PubMed

    Zhang, Hongjun; Ju, Baoling; Zhang, Xiaoli; Zhu, Yanfei; Nie, Ying; Xu, Yuanhong; Lei, Qiuxia

    2017-06-01

    Magnolol is a pharmacological biphenolic compound extracted from Chinese herb Magnolia officinalis, which displays anti-inflammatory and antioxidant effects. This study was aimed at exploring the potential effect of magnolol on immune-related liver fibrosis. Herein, BALB/c mice were injected with concanavalin A (ConA, 8 mg/kg/week) up to 6 weeks to establish hepatic fibrosis, and magnolol (10, 20, 30 mg/kg/day) was given to these mice orally throughout the whole experiment. We found that magnolol preserved liver function and attenuated liver fibrotic injury in vivo. In response to ConA stimulation, the CD4 + T cells preferred to polarizing towards CD4 + T helper 17 (Th17) cells in liver. Magnolol was observed to inhibit Th17 cell differentiation in ConA-treated liver in addition to suppressing interleukin (IL)-17A generation. Hepatic stellate cells were activated in fibrotic liver as demonstrated by increased alpha smooth muscle actin (α-SMA) and desmin. More transforming growth factor (TGF)-β1 and activin A were secreted into the serum. Magnolol suppressed this abnormal HSC activation. Furthermore, the phosphorylation of Smad3 in its linker area (Thr179, Ser 204/208/213) was inhibited by magnolol. In vitro, the recombinant IL-17A plus TGF-β1 or activin A induced activation of human LX2 HSCs and promoted their collagen production. Smad3/Smad4 signalling pathway was activated in LX2 cells exposed to the fibrotic stimuli, as illustrated by the up-regulated phospho-Smad3 and the enhanced interaction between Smad3 and Smad4. These alterations were suppressed by magnolol. Collectively, our study reveals a novel antifibrotic effect of magnolol on Th17 cell-mediated fibrosis. © 2017 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  11. Attraction thresholds and sex discrimination of urinary odorants in male and female aromatase knockout (ArKO) mice.

    PubMed

    Pierman, Sylvie; Douhard, Quentin; Balthazart, Jacques; Baum, Michael J; Bakker, Julie

    2006-01-01

    We previously found that both male and female aromatase knockout (ArKO) mice, which cannot synthesize estrogens due to a targeted mutation of the aromatase gene, showed less investigation of volatile body odors from anesthetized conspecifics of both sexes in Y-maze tests. We now ask whether ArKO mice are in fact capable of discriminating between and/or responding to volatile odors. Using habituation/dishabituation tests, we found that gonadectomized ArKO and wild-type (WT) mice of both sexes, which were tested without any sex hormone replacement, reliably distinguished between undiluted volatile urinary odors of either adult males or estrous females versus deionized water as well as between these two urinary odors themselves. However, ArKO mice of both sexes were less motivated than WT controls to investigate same-sex odors when they were presented last in the sequence of stimuli. In a second experiment, we compared the ability of ArKO and WT mice to respond to decreasing concentrations of either male or female urinary odors. We found a clear-cut sex difference in urinary odor attraction thresholds among WT mice: WT males failed to respond to urine dilutions higher than 1:20 by volume, whereas WT females continued to respond to urine dilutions up to 1:80. Male ArKO mice resembled WT females in their ability to respond to lower concentrations of urinary odors, raising the possibility that the observed sex difference among WT mice in urine attraction thresholds results from the perinatal actions of estrogen in the male nervous system. Female ArKO mice failed to show significant dishabituation responses to two (1:20 and 1:80) dilutions of female urine, perhaps, again, because of a reduced motivation to investigate less salient, same-sex urinary odors. Previously observed deficits in the preference of ArKO male and female mice to approach volatile body odors from conspecifics of either sex cannot be attributed to an inability of ArKO subjects to discriminate these

  12. Skeletal effects of estrogen deficiency as induced by an aromatase inhibitor in an aged male rat model.

    PubMed

    Vanderschueren, D; Boonen, S; Ederveen, A G; de Coster, R; Van Herck, E; Moermans, K; Vandenput, L; Verstuyf, A; Bouillon, R

    2000-11-01

    Aromatization of androgens into estrogens may be important for maintenance of the male skeleton. To address this hypothesis, we evaluated the skeletal effects of selective estrogen deficiency as induced by the aromatase inhibitor vorozole (Vor), with or without 17beta-estradiol (E(2)) administration (1.35 microg/day), in aged (12-month-old) male rats. A baseline group was killed at the start of the experiment (Base). The control group (Control), the group treated with vorozole alone (Vor), the group treated with E(2) alone (E(2)), or the group with a combination of both (Vor + E(2)) were killed 15 weeks later. Vorozole significantly increased serum testosterone (T) and reduced serum E(2) compared with Control. Body weight gain and serum insulin-like growth factor-I (IGF-I) were also lower in Vor, whereas significant weight loss and decrease of serum IGF-I occurred as a result of E(2) administration. Bone formation as assessed by serum osteocalcin was unaffected but osteoid surface in the proximal metaphysis of the tibia was increased in Vor-treated rats. Bone resorption as evaluated by urinary deoxypyridinoline excretion was increased in Vor. Biochemical parameters of bone turnover were reduced significantly in all E(2) treated rats. Premature closure of the growth plates and decreased osteoid and mineralizing surfaces were also observed in E(2) and Vor + E(2). Apparent bone density of lumbar vertebrae and femur, as measured by dual-energy X-ray absorptiometry (DXA), was significantly reduced in Vor. Vorozole decreased femoral bone density mainly in the distal femur (trabecular and cortical region). This decrease of bone density was not present in E(2) and Vor + E(2). Similar findings were observed when bone density was assessed by peripheral quantitative computed tomography (pQCT); that is, trabecular density of the distal femur, the proximal tibia, and the distal lumbar vertebra were all lower in Vor. This decrease in density was not observed in all E(2)-treated

  13. Linking the response of endocrine regulated genes to adverse effects on sex differentiation improves comprehension of aromatase inhibition in a Fish Sexual Development Test.

    PubMed

    Muth-Köhne, Elke; Westphal-Settele, Kathi; Brückner, Jasmin; Konradi, Sabine; Schiller, Viktoria; Schäfers, Christoph; Teigeler, Matthias; Fenske, Martina

    2016-07-01

    The Fish Sexual Development Test (FSDT) is a non-reproductive test to assess adverse effects of endocrine disrupting chemicals. With the present study it was intended to evaluate whether gene expression endpoints would serve as predictive markers of endocrine disruption in a FSDT. For proof-of-concept, a FSDT according to the OECD TG 234 was conducted with the non-steroidal aromatase inhibitor fadrozole (test concentrations: 10μg/L, 32μg/L, 100μg/L) using zebrafish (Danio rerio). Gene expression analyses using quantitative RT-PCR were included at 48h, 96h, 28days and 63days post fertilization (hpf, dpf). The selection of genes aimed at finding molecular endpoints which could be directly linked to the adverse apical effects of aromatase inhibition. The most prominent effects of fadrozole exposure on the sexual development of zebrafish were a complete sex ratio shift towards males and an acceleration of gonad maturation already at low fadrozole concentrations (10μg/L). Due to the specific inhibition of the aromatase enzyme (Cyp19) by fadrozole and thus, the conversion of C19-androgens to C18-estrogens, the steroid hormone balance controlling the sex ratio of zebrafish was altered. The resulting key event is the regulation of directly estrogen-responsive genes. Subsequently, gene expression of vitellogenin 1 (vtg1) and of the aromatase cyp19a1b isoform (cyp19a1b), were down-regulated upon fadrozole treatment compared to controls. For example, mRNA levels of vtg1 were down-regulated compared to the controls as early as 48 hpf and 96 hpf. Further regulated genes cumulated in pathways suggested to be controlled by endocrine mechanisms, like the steroid and terpenoid synthesis pathway (e.g. mevalonate (diphospho) decarboxylase (mvd), lanosterol synthase (2,3-oxidosqualene-lanosterol cyclase; lss), methylsterol monooxygenase 1 (sc4mol)) and in lipid transport/metabolic processes (steroidogenic acute regulatory protein (star), apolipoprotein Eb (apoEb)). Taken together

  14. Predicting Adherence to Aromatase Inhibitor Therapy among Breast Cancer Survivors: An Application of the Protection Motivation Theory

    PubMed Central

    Karmakar, Monita; Pinto, Sharrel L; Jordan, Timothy R; Mohamed, Iman; Holiday-Goodman, Monica

    2017-01-01

    The purpose of this observational study was to determine if the Protection Motivation Theory could predict and explain adherence to aromatase inhibitor (AI) therapy among breast cancer survivors. Purposive sampling was used to identify 288 survivors who had been prescribed AI therapy. A valid and reliable survey was mailed to survivors. A total of 145 survivors completed the survey. The Morisky scale was used to measure adherence to AI. The survivors reported a mean score of 6.84 (±0.66) on the scale. Nearly 4 in 10 survivors (38%) were non-adherent. Adherence differed by age, marital status, insurance status, income, and presence of co-morbid conditions. Self-efficacy (r=0.485), protection motivation (r=0.310), and Response Efficacy (r=0.206) were positively and significantly correlated with adherence. Response Cost (r=-0.235) was negatively correlated with adherence. The coping appraisal constructs were statistically significant predictors medication adherence (β=0.437) with self-efficacy being the strongest significant predictor of adherence (β = 0.429). PMID:28469437

  15. Predicting Adherence to Aromatase Inhibitor Therapy among Breast Cancer Survivors: An Application of the Protection Motivation Theory.

    PubMed

    Karmakar, Monita; Pinto, Sharrel L; Jordan, Timothy R; Mohamed, Iman; Holiday-Goodman, Monica

    2017-01-01

    The purpose of this observational study was to determine if the Protection Motivation Theory could predict and explain adherence to aromatase inhibitor (AI) therapy among breast cancer survivors. Purposive sampling was used to identify 288 survivors who had been prescribed AI therapy. A valid and reliable survey was mailed to survivors. A total of 145 survivors completed the survey. The Morisky scale was used to measure adherence to AI. The survivors reported a mean score of 6.84 (±0.66) on the scale. Nearly 4 in 10 survivors (38%) were non-adherent. Adherence differed by age, marital status, insurance status, income, and presence of co-morbid conditions. Self-efficacy (r=0.485), protection motivation (r=0.310), and Response Efficacy (r=0.206) were positively and significantly correlated with adherence. Response Cost (r=-0.235) was negatively correlated with adherence. The coping appraisal constructs were statistically significant predictors medication adherence (β=0.437) with self-efficacy being the strongest significant predictor of adherence (β = 0.429).

  16. Aromatase gene polymorphism does not influence clinical phenotype and response to oral contraceptive pills in polycystic ovary syndrome women.

    PubMed

    Maier, Polyana S; Spritzer, Poli Mara

    2012-01-01

    To assess whether a single nucleotide polymorphism (SNP50) of the aromatase gene (CYP19) is associated with polycystic ovary syndrome (PCOS) phenotypes and to investigate the influence of this polymorphism on the response of PCOS to treatment with oral contraceptive pills (OCP). 162 hirsute women were stratified into a classic PCOS group (hyperandrogenism, ovulatory dysfunction, c-PCOS) and an ovulatory PCOS group (hyperandrogenism, ovulatory cycles, polycystic ovaries, ov-PCOS). 51 women completed a 6-month OCP trial (20 µg ethinyl estradiol + 75 µg gestodene, 21/28 days per cycle, plus 100 mg spironolactone in 32 women with moderate to severe hirsutism). We considered the presence of the polymorphic allele A (AG+AA) in comparison to the absence of the polymorphism (GG) to express results and to perform the comparisons regarding clinical variables. Mean age was 23.3 ± 6.9 years. Hirsutism score was similar in c-PCOS and ov-PCOS (15 (11-20) vs. 13 (11-20)). The differences in hormone and metabolic variables between phenotypes were independent of the presence of allele A. In the OCP trial subsample, no differences were observed between genotypes after 6 months' treatment. The differences between c-PCOS and ov-PCOS cannot be explained by the genetic variation at SNP50 in the CYP19 gene. Copyright © 2012 S. Karger AG, Basel.

  17. High progesterone levels during the luteal phase related to the use of an aromatase inhibitor in breast cancer patients.

    PubMed

    Alviggi, C; Marci, R; Vallone, R; Conforti, A; Di Rella, F; Strina, I; Picarelli, S; De Rosa, P; De Laurentiis, M; Yding Andersen, C; De Placido, G

    2017-07-01

    To evaluate the hormonal profile in three breast cancer patients who underwent controlled ovarian stimulation in the presence of the aromatase inhibitor letrozole. In IVF University referral center, a case series of three breast cancer patients who underwent controlled ovarian stimulation (COS) with recombinant FSH and letrozole were investigated. Ovulation was induced with hCG (case No. 1) or with GnRH agonist (case No. 2-3). The primary outcome of our study was the detection of progesterone levels in the luteal phase. Very high progesterone values (mean 186.6 ± 43.6 ng/mL) during the luteal phase were recorded in all three cases. High progesterone levels can be related to the use of letrozole independently of the most commonly used trigger regimen. Although progesterone has long been considered a protective factor against breast cancer, several studies have demonstrated that progesterone could expand a transformation-sensitive stem cell population in the mammary glands. The estrogen negative feedback effect on the hypothalamus-pituitary axis and the disruption of steroid biosynthesis and could represent an intriguing reason behind this phenomenon. Our results highlight the need to evaluate further the increase in progesterone levels in the luteal phase in women with breast cancer undergoing COS with letrozole.

  18. Natural Products as Anticancerous Therapeutic Molecules with Special Reference to Enzymatic Targets Topoisomerase, COX, LOX and Aromatase.

    PubMed

    Singh, Swati; Awasthi, Manika; Pandey, Veda P; Dwivedi, Upendra N

    2018-01-01

    Cancer, characterized by uncontrolled growth and proliferation of cells, is affecting millions of people every year and estimated as the second leading cause of death. Its successful treatment yet remains a challenge due to the lack of selectivity, toxicity and the development of multidrug resistant cells to the currently available drugs. Plant derived natural products hold great promise for discovery and development of new pharmaceuticals against cancer as evident by the fact that out of 121 drugs prescribed for cancer treatment till date, 90 are derived from plant sources. Furthermore, the plant derived therapeutic molecules are also considered as safer substitutes to those of synthetic ones. In this review, the therapeutic potentials of plant derived natural products belonging to secondary metabolites, namely alkaloids, flavonoids and terpenoids as anticancer molecules, involving various strategies of treatment, have been discussed with special reference to topoisomerases (Topo), cyclooxygenases (COX), lipoxygenase (LOX) and aromatase as enzymatic targets for various types of cancers. Furthermore, in view of the recent advances made in the field of computer aided drug design, the present review also discusses the use of computational approaches such as ADMET, molecular docking, molecular dynamics simulation and QSAR to assess and predict the safety, efficacy, potency and identification of such potent anticancerous therapeutic molecules. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Marked increase of final height by long-term aromatase inhibition in a boy with idiopathic short stature.

    PubMed

    Krebs, Andreas; Moske-Eick, Olaf; Doerfer, Jürgen; Roemer-Pergher, Cordula; van der Werf-Grohmann, Natascha; Schwab, Karl Otfried

    2012-01-01

    Growth hormone (GH) is the most frequently used treatment in children with idiopathic short stature (ISS). Aromatase inhibitor (AI) therapy is still in an experimental state, and both final height (FH) and long-term efficacy data in ISS have not been published. We present a 14.5-year-old boy with ISS and a height of 142.7 cm [standard deviation score (SDS) -2.79]. Based on the baseline bone age (BA) of 13.5-14 years, his predicted adult height (PAH) by Bayley/Pinneau was 154 cm (SDS -3.77)-158.2 (SDS -3.15). After a 5-year letrozole monotherapy, FH was 169 cm (SDS -1.57) showing a height difference between PAH and FH from 10.8 to 15 cm. No permanent side effects of the medication have been observed. Both a transient occurrence and a spontaneous recovery of decreased bone mineral apparent density were seen, verified by dual-energy X-ray absorptiometry. Spinal magnetic resonance imaging revealed no vertebral abnormalities. All therapy might be an effective and low-cost alternative to the use of GH. Further controlled trials should prove efficacy and safety of long-term AI therapy in boys with ISS.

  20. Protectin D1 reduces concanavalin A-induced liver injury by inhibiting NF-κB-mediated CX3CL1/CX3CR1 axis and NLR family, pyrin domain containing 3 inflammasome activation.

    PubMed

    Ren, Jun; Meng, Shanshan; Yan, Bingdi; Yu, Jinyan; Liu, Jing

    2016-04-01

    Protectin D1 (PD1) is a bioactive product generated from docosahexaenoic acid, which may exert anti-inflammatory effects in various inflammatory diseases. However, the underlying molecular mechanism of its anti‑inflammatory activity on concanavalin A (Con A)-induced hepatitis remains unknown. The aim of the present study was to investigate the protective effects of PD1 against Con A‑induced liver injury and the underlying mechanisms via intravenous injection of PD1 prior to Con A administration. C57BL/6 mice were randomly divided into four experimental groups as follows: Control group, Con A group (30 mg/kg), 20 µg/kg PD1 + Con A (30 mg/kg) group and 10 µg/kg PD1 + Con A (30 mg/kg) group. PD1 pretreatment was demonstrated to significantly inhibit elevated plasma aminotransferase levels, high mobility group box 1 and liver necrosis, which were observed in Con A‑induced hepatitis. Furthermore, compared with the Con A group, PD1 pretreatment prevented the production of pro‑inflammatory cytokines, including tumor necrosis factor‑α, interferon‑γ and interleukin‑2, ‑1β and ‑6. In addition, pretreatment with PD1 markedly downregulated cluster of differentiation (CD)4+, CD8+ and natural killer T (NKT) cell infiltration in the liver. PD1 pretreatment was observed to suppress the messenger RNA and protein expression levels of NLR family, pyrin domain containing 3 and Toll‑like receptor (TLR) 4 in liver tissue samples. Further data indicated that PD1 pretreatment inhibited the activation of the nuclear factor κ‑light‑chain‑enhancer of activated B cells (NF‑κB) signaling pathway and chemokine (C‑X3‑C motif) ligand 1 (CX3CL1)/chemokine (C-X3-C motif) receptor 1 (CX3CR1) axis by preventing phosphorylation of nuclear factor of κ light polypeptide gene enhancer in B-cells inhibitor, α and NF‑κB in Con A‑induced liver injury. Therefore, these results suggest that PD1 administration protects mice against Con A‑induced liver injury via

  1. A game of two? Gene expression analysis of brain (cyp19a1b) and gonadal (cyp19a1a) aromatase in females of a Neotropical cichlid fish through the parental care period and removal of the offspring.

    PubMed

    Ramallo, Martín R; Honji, Renato M; Birba, Agustina; Morandini, Leonel; Varela, María L; Genovese, Griselda; Moreira, Renata G; Somoza, Gustavo M; Pandolfi, Matías

    2017-10-01

    For many species parental behavior is essential for the survival of the offspring. While the ultimate causes of teleost parental behavior have been widely studied, comparatively little is known about its proximate causes. The aim of this study was to analyze the yet unexplored, potential dual role of brain and gonadal aromatases, the enzymes responsible for the conversion of androgens to estrogens in the brains and gonads of teleosts, respectively, on the different stages of the maternal care period of the biparental cichlid Cichlasoma dimerus, locally known as chanchita. By immunohistochemistry we analyzed the neural distribution of brain aromatase and observed it exclusively within the forebrain, including areas involved in the regulation of parental behavior. We next analyzed the gene expression of brain aromatase in the brain, and gonadal aromatase in the ovary, of female chanchitas through the parental care period. To further characterize the physiological environment associated to maternal care, we also evaluated sex steroid levels (17β-estradiol, testosterone and 11-ketotestoterone) and ovarian follicle percentage. The onset of parental behavior specifically downregulated sex steroids synthesis and the rate of ovarian maturation, as denoted by a more than 10-fold decrease in steroid levels and delayed detection of mature follicles in females with offspring, compared to females which eggs were removed. Gene expression levels of both aromatases were independent of maternal care at the evaluated time points, even though they varied during the parental care period. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. An Intron 9 CYP19 Gene Variant (IVS9+5G>A), Present in an Aromatase-Deficient Girl, Affects Normal Splicing and Is Also Present in Normal Human Steroidogenic Tissues.

    PubMed

    Saraco, Nora; Nesi-Franca, Suzana; Sainz, Romina; Marino, Roxana; Marques-Pereira, Rosana; La Pastina, Julia; Perez Garrido, Natalia; Sandrini, Romolo; Rivarola, Marco Aurelio; de Lacerda, Luiz; Belgorosky, Alicia

    2015-01-01

    Splicing CYP19 gene variants causing aromatase deficiency in 46,XX disorder of sexual development (DSD) patients have been reported in a few cases. A misbalance between normal and aberrant splicing variants was proposed to explain spontaneous pubertal breast development but an incomplete sex maturation progress. The aim of this study was to functionally characterize a novel CYP19A1 intronic homozygote mutation (IVS9+5G>A) in a 46,XX DSD girl presenting spontaneous breast development and primary amenorrhea, and to evaluate similar splicing variant expression in normal steroidogenic tissues. Genomic DNA analysis, splicing prediction programs, splicing assays, and in vitro protein expression and enzyme activity analyses were carried out. CYP19A1 mRNA expression in human steroidogenic tissues was also studied. A novel IVS9+5G>A homozygote mutation was found. In silico analysis predicts the disappearance of the splicing donor site in intron 9, confirmed by patient peripheral leukocyte cP450arom and in vitro studies. Protein analysis showed a shorter and inactive protein. The intron 9 transcript variant was also found in human steroidogenic tissues. The mutation IVS9+5G>A generates a splicing variant that includes intron 9 which is also present in normal human steroidogenic tissues, suggesting that a misbalance between normal and aberrant splicing variants might occur in target tissues, explaining the clinical phenotype in the affected patient. © 2015 S. Karger AG, Basel.

  3. GP88 (PC-Cell Derived Growth Factor, progranulin) stimulates proliferation and confers letrozole resistance to aromatase overexpressing breast cancer cells

    PubMed Central

    2011-01-01

    Background Aromatase inhibitors (AI) that inhibit breast cancer cell growth by blocking estrogen synthesis have become the treatment of choice for post-menopausal women with estrogen receptor positive (ER+) breast cancer. However, some patients display de novo or acquired resistance to AI. Interactions between estrogen and growth factor signaling pathways have been identified in estrogen-responsive cells as one possible reason for acquisition of resistance. Our laboratory has characterized an autocrine growth factor overexpressed in invasive ductal carcinoma named PC-Cell Derived Growth Factor (GP88), also known as progranulin. In the present study, we investigated the role GP88 on the acquisition of resistance to letrozole in ER+ breast cancer cells Methods We used two aromatase overexpressing human breast cancer cell lines MCF-7-CA cells and AC1 cells and their letrozole resistant counterparts as study models. Effect of stimulating or inhibiting GP88 expression on proliferation, anchorage-independent growth, survival and letrozole responsiveness was examined. Results GP88 induced cell proliferation and conferred letrozole resistance in a time- and dose-dependent fashion. Conversely, naturally letrozole resistant breast cancer cells displayed a 10-fold increase in GP88 expression when compared to letrozole sensitive cells. GP88 overexpression, or exogenous addition blocked the inhibitory effect of letrozole on proliferation, and stimulated survival and soft agar colony formation. In letrozole resistant cells, silencing GP88 by siRNA inhibited cell proliferation and restored their sensitivity to letrozole. Conclusion Our findings provide information on the role of an alternate growth and survival factor on the acquisition of aromatase inhibitor resistance in ER+ breast cancer. PMID:21658239

  4. Electroacupuncture for fatigue, sleep, and psychological distress in breast cancer patients with aromatase inhibitor-related arthralgia: a randomized trial.

    PubMed

    Mao, Jun J; Farrar, John T; Bruner, Deborah; Zee, Jarcy; Bowman, Marjorie; Seluzicki, Christina; DeMichele, Angela; Xie, Sharon X

    2014-12-01

    Although fatigue, sleep disturbance, depression, and anxiety are associated with pain in breast cancer patients, it is unknown whether acupuncture can decrease these comorbid symptoms in cancer patients with pain. The objective of this study was to evaluate the effect of electroacupuncture (EA) on fatigue, sleep, and psychological distress in breast cancer survivors who experience joint pain related to aromatase inhibitors (AIs). The authors performed a randomized controlled trial of an 8-week course of EA compared with a waitlist control (WLC) group and a sham acupuncture (SA) group in postmenopausal women with breast cancer who self-reported joint pain attributable to AIs. Fatigue, sleep disturbance, anxiety, and depression were measured using the Brief Fatigue Inventory (BFI), the Pittsburgh Sleep Quality Index (PSQI), and the Hospital Anxiety and Depression Scale (HADS). The effects of EA and SA versus WLC on these outcomes were evaluated using mixed-effects models. Of the 67 randomly assigned patients, baseline pain interference was associated with fatigue (Pearson correlation coefficient [r]=0.75; P < .001), sleep disturbance (r=0.38; P=.0026), and depression (r=0.58; P < .001). Compared with the WLC condition, EA produced significant improvements in fatigue (P=.0095), anxiety (P=.044), and depression (P=.015) and a nonsignificant improvement in sleep disturbance (P=.058) during the 12-week intervention and follow-up period. In contrast, SA did not produce significant reductions in fatigue or anxiety symptoms but did produce a significant improvement in depression compared with the WLC condition (P=.0088). Compared with usual care, EA produced significant improvements in fatigue, anxiety, and depression; whereas SA improved only depression in women experiencing AI-related arthralgia. © 2014 American Cancer Society.

  5. Targeted Metabolomics Approach To Detect the Misuse of Steroidal Aromatase Inhibitors in Equine Sports by Biomarker Profiling.

    PubMed

    Chan, George Ho Man; Ho, Emmie Ngai Man; Leung, David Kwan Kon; Wong, Kin Sing; Wan, Terence See Ming

    2016-01-05

    The use of anabolic androgenic steroids (AAS) is prohibited in both human and equine sports. The conventional approach in doping control testing for AAS (as well as other prohibited substances) is accomplished by the direct detection of target AAS or their characteristic metabolites in biological samples using hyphenated techniques such as gas chromatography or liquid chromatography coupled with mass spectrometry. Such an approach, however, falls short when dealing with unknown designer steroids where reference materials and their pharmacokinetics are not available. In addition, AASs with fast elimination times render the direct detection approach ineffective as the detection window is short. A targeted metabolomics approach is a plausible alternative to the conventional direct detection approach for controlling the misuse of AAS in sports. Because the administration of AAS of the same class may trigger similar physiological responses or effects in the body, it may be possible to detect such administrations by monitoring changes in the endogenous steroidal expression profile. This study attempts to evaluate the viability of using the targeted metabolomics approach to detect the administration of steroidal aromatase inhibitors, namely androst-4-ene-3,6,17-trione (6-OXO) and androsta-1,4,6-triene-3,17-dione (ATD), in horses. Total (free and conjugated) urinary concentrations of 31 endogenous steroids were determined by gas chromatography-tandem mass spectrometry for a group of 2 resting and 2 in-training thoroughbred geldings treated with either 6-OXO or ATD. Similar data were also obtained from a control (untreated) group of in-training thoroughbred geldings (n = 28). Statistical processing and chemometric procedures using principle component analysis and orthogonal projection to latent structures-discriminant analysis (OPLS-DA) have highlighted 7 potential biomarkers that could be used to differentiate urine samples obtained from the control and the treated groups

  6. Periodontal Health in Women With Early-Stage Postmenopausal Breast Cancer Newly on Aromatase Inhibitors: A Pilot Study.

    PubMed

    Taichman, L Susan; Inglehart, Marita R; Giannobile, William V; Braun, Thomas; Kolenic, Giselle; Van Poznak, Catherine

    2015-07-01

    Aromatase inhibitor (AI) use results in low estrogen levels, which in turn affect bone mineral density (BMD). Periodontitis, alveolar bone loss, and tooth loss are associated with low BMD. The goal of this study is to assess the prevalence of periodontitis and perceived oral health and evaluate salivary biomarkers in postmenopausal women who are survivors of early-stage (I to IIIA) breast cancer (BCa) and receive adjuvant AI therapy. Participants included 58 postmenopausal women: 29 with BCa on AIs and 29 controls without BCa diagnoses. Baseline periodontal status was assessed with: 1) periodontal probing depth (PD); 2) bleeding on probing (BOP); and 3) attachment loss (AL). Demographic and dental utilization information was gathered by questionnaire. Linear regression modeling was used to analyze the outcomes. No differences were found in mean PD or number of teeth. The AI group had significantly more sites with BOP (27.8 versus 16.7; P = 0.02), higher worst-site AL (5.2 versus 4.0 mm; P <0.01), and more sites with dental calculus (18.2 versus 6.4; P <0.001) than controls. Linear regression adjusted for income, tobacco use, dental insurance, and previous radiation and chemotherapy exposure demonstrated that AI use increased AL by >2 mm (95% confidence interval, 0.46 to 3.92). Median salivary osteocalcin and tumor necrosis factor-α levels were significantly higher in the AI group than the control group. This first investigation of the periodontal status of women initiating adjuvant AI therapy identifies this population as having an increased risk for periodontitis.

  7. Vitamin D threshold to prevent aromatase inhibitor-related bone loss: the B-ABLE prospective cohort study.

    PubMed

    Prieto-Alhambra, Daniel; Servitja, Sonia; Javaid, M Kassim; Garrigós, Laia; Arden, Nigel K; Cooper, Cyrus; Albanell, Joan; Tusquets, Ignasi; Diez-Perez, Adolfo; Nogues, Xavier

    2012-06-01

    Aromatase inhibitor (AI)-related bone loss is associated with increased fracture rates. Vitamin D might play a role in minimising this effect. We hypothesised that 25-hydroxy-vitamin D concentrations [25(OH)D] after 3 months supplementation might relate to bone loss after 1 year on AI therapy. We conducted a prospective cohort study from January 2006 to December 2011 of a consecutive sample of women initiating AI for early breast cancer who were ineligible for bisphosphonate therapy and stayed on treatment for 1 year (N = 232). Serum 25(OH)D was measured at baseline and 3 months, and lumbar spine (LS) bone mineral density at baseline and 1 year. Subjects were supplemented with daily calcium (1 g) and vitamin D(3) (800 IU) and additional oral 16,000 IU every 2 weeks if baseline 25(OH)D was <30 ng/ml. Linear regression models were fitted to adjust for potential confounders. After 1 year on AI therapy, 232 participants experienced a significant 1.68 % [95 % CI 1.15-2.20 %] bone loss at LS (0.017 g/cm(2) [0.012-0.024], P < 0.0001). Higher 25(OH)D at 3 months protected against LS bone loss (-0.5 % per 10 ng/ml [95 % CI -0.7 to -0.3 %], adjusted P = 0.0001), and those who reached levels ≥40 ng/ml had reduced bone loss by 1.70 % [95 % CI 0.4-3.0 %; adjusted P = 0.005] compared to those with low 25(OH)D levels (<30 ng/ml). We conclude that improved vitamin D status using supplementation is associated with attenuation of AI-associated bone loss. For this population, the current Institute of Medicine target recommendation of 20 ng/ml might be too low to ensure good bone health.

  8. Randomized placebo-controlled pilot trial of omega 3 fatty acids for prevention of aromatase inhibitor-induced musculoskeletal pain.

    PubMed

    Lustberg, Maryam B; Orchard, Tonya S; Reinbolt, Raquel; Andridge, Rebecca; Pan, Xueliang; Belury, Martha; Cole, Rachel; Logan, Amanda; Layman, Rachel; Ramaswamy, Bhuvaneswari; Wesolowski, Robert; Berger, Michael; Patterson, Elaine; Loprinzi, Charles; Shapiro, Charles L; Yee, Lisa

    2018-02-01

    Aromatase inhibitor (AI)-induced joint symptoms negatively impact drug adherence and quality of life in breast cancer survivors. Mechanisms underlying symptoms may include inflammation. It is hypothesized that n - 3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory properties and may reduce symptoms. We conducted a randomized, double-blind, placebo-controlled study comparing 4.3 g/day n - 3 PUFA supplements vs placebo for 24 weeks in postmenopausal breast cancer patients starting adjuvant AIs. Primary endpoints were adherence and tolerability; secondary outcomes included inflammatory cytokines and symptoms assessed by the Brief Pain Inventory short form (BPI-SF) and Functional Assessment of Cancer Treatment-Endocrine Symptoms (FACT-ES) at 0, 12, and 24 weeks. Forty-four women were randomized, of which 35 completed the study. Adherence was ≥ 88% based on these 35 patients with pill counts as well as change in red blood cell (RBC) n - 3 PUFAs. Common toxicities included grade 1 flatulence (55% of both groups) and belching (45% of n - 3 group). Mean pain severity scores (BPI-SF) did not change significantly by time or treatment arm. Quality of life, based on FACT-ES scores, significantly decreased within placebo (p = 0.04), but not the n - 3 group (p = 0.58), with a trend toward between-group differences (p = 0.06) at 12 weeks, but no significant differences at 24 weeks. RBC n - 3 levels were strongly positively correlated with FACT-ES at 12 weeks, but attenuated at 24 weeks. High-dose n - 3 PUFA supplementation is feasible and well tolerated when administered with AIs. Additional studies are needed to evaluate efficacy in prevention of joint symptoms.

  9. Incidence and management of arthralgias in breast cancer patients treated with aromatase inhibitors in an outpatient oncology clinic.

    PubMed

    Menas, Pamela; Merkel, Douglas; Hui, Wendy; Lawton, Jessica; Harper, Abigail; Carro, George

    2012-12-01

    Aromatase inhibitors (AIs) are routinely used as first-line adjuvant treatment of breast cancer in postmenopausal women with hormone receptor positive tumors. The current recommended length of treatment with an AI is 5 years. Arthralgias have been frequently cited as the primary reason for discontinuation of AI therapy. Various treatment strategies are proposed in literature, but a standardized treatment algorithm has not been established. The initial purpose of this study was to describe the incidence and management of AI-induced arthralgias in patients treated at Kellogg Cancer Center (KCC). Further evaluation led to the development and the implementation of a treatment algorithm and electronic medical record (EMR) documentation tools. The retrospective chart review included 206 adult patients with hormone receptor positive breast cancer who were receiving adjuvant therapy with an AI. A multidisciplinary treatment team consisting of pharmacists, collaborative practice nurses, and physicians met to develop a standardized treatment algorithm and corresponding EMR documentation tool. The treatment algorithm and documentation tool were developed after the study to better monitor and proactively treat patients with AI-induced arthralgias. RESULTS/ CONCLUSIONS: The overall incidence of arthralgias at KCC was 48% (n = 98/206). Of these patients, 32% were documented as having arthralgias within the first 6 months of therapy initiation. Patients who reported AI-induced arthralgias were younger than patients who did not report AI-induced arthralgias (61 vs. 65 years, p = 0.002). There was no statistical difference in the incidence of arthralgias in patients with a history of chemotherapy (including taxane therapy) compared to those who did not receive chemotherapy (p = 0.352). Of patients presenting with AI-induced arthralgias, 41% did not have physician-managed treatment documented in the EMR. A standardized treatment algorithm and electronic chart

  10. Kinetics, prognostic and predictive values of ESR1 circulating mutations in metastatic breast cancer patients progressing on aromatase inhibitor

    PubMed Central

    Clatot, Florian; Perdrix, Anne; Augusto, Laetitia; Beaussire, Ludivine; Delacour, Julien; Calbrix, Céline; Sefrioui, David; Viailly, Pierre-Julien; Bubenheim, Michael; Moldovan, Cristian; Alexandru, Cristina; Tennevet, Isabelle; Rigal, Olivier; Guillemet, Cécile; Leheurteur, Marianne; Gouérant, Sophie; Petrau, Camille; Théry, Jean-Christophe; Picquenot, Jean-Michel; Veyret, Corinne; Frébourg, Thierry; Jardin, Fabrice

    2016-01-01

    Purpose To assess the prognostic and predictive value of circulating ESR1 mutation and its kinetics before and after progression on aromatase inhibitor (AI) treatment. Patients and methods ESR1 circulating D538G and Y537S/N/C mutations were retrospectively analyzed by digital droplet PCR after first-line AI failure in patients treated consecutively from 2010 to 2012 for hormone receptor-positive metastatic breast cancer. Progression-free survival (PFS) and overall survival (OS) were analyzed according to circulating mutational status and subsequent lines of treatment. The kinetics of ESR1 mutation before (3 and 6 months) and after (3 months) AI progression were determined in the available archive plasmas. Results Circulating ESR1 mutations were found at AI progression in 44/144 patients included (30.6%). Median follow-up from AI initiation was 40 months (range 4-94). The median OS was decreased in patients with circulating ESR1 mutation than in patients without mutation (15.5 versus 23.8 months, P=0.0006). The median PFS was also significantly decreased in patients with ESR1 mutation than in patients without mutation (5.9 vs 7 months, P=0.002). After AI failure, there was no difference in outcome for patients receiving chemotherapy (n = 58) versus non-AI endocrine therapy (n=51) in patients with and without ESR1 mutation. ESR1 circulating mutations were detectable in 75% of all cases before AI progression, whereas the kinetics 3 months after progression did not correlate with outcome. Conclusion ESR1 circulating mutations are independent risk factors for poor outcome after AI failure, and are frequently detectable before clinical progression. Interventional studies based on ESR1 circulating status are warranted. PMID:27801670

  11. Kinetics, prognostic and predictive values of ESR1 circulating mutations in metastatic breast cancer patients progressing on aromatase inhibitor.

    PubMed

    Clatot, Florian; Perdrix, Anne; Augusto, Laetitia; Beaussire, Ludivine; Delacour, Julien; Calbrix, Céline; Sefrioui, David; Viailly, Pierre-Julien; Bubenheim, Michael; Moldovan, Cristian; Alexandru, Cristina; Tennevet, Isabelle; Rigal, Olivier; Guillemet, Cécile; Leheurteur, Marianne; Gouérant, Sophie; Petrau, Camille; Théry, Jean-Christophe; Picquenot, Jean-Michel; Veyret, Corinne; Frébourg, Thierry; Jardin, Fabrice; Sarafan-Vasseur, Nasrin; Di Fiore, Frédéric

    2016-11-15

    To assess the prognostic and predictive value of circulating ESR1 mutation and its kinetics before and after progression on aromatase inhibitor (AI) treatment. ESR1 circulating D538G and Y537S/N/C mutations were retrospectively analyzed by digital droplet PCR after first-line AI failure in patients treated consecutively from 2010 to 2012 for hormone receptor-positive metastatic breast cancer. Progression-free survival (PFS) and overall survival (OS) were analyzed according to circulating mutational status and subsequent lines of treatment. The kinetics of ESR1 mutation before (3 and 6 months) and after (3 months) AI progression were determined in the available archive plasmas. Circulating ESR1 mutations were found at AI progression in 44/144 patients included (30.6%). Median follow-up from AI initiation was 40 months (range 4-94). The median OS was decreased in patients with circulating ESR1 mutation than in patients without mutation (15.5 versus 23.8 months, P=0.0006). The median PFS was also significantly decreased in patients with ESR1 mutation than in patients without mutation (5.9 vs 7 months, P=0.002). After AI failure, there was no difference in outcome for patients receiving chemotherapy (n = 58) versus non-AI endocrine therapy (n=51) in patients with and without ESR1 mutation. ESR1 circulating mutations were detectable in 75% of all cases before AI progression, whereas the kinetics 3 months after progression did not correlate with outcome. ESR1 circulating mutations are independent risk factors for poor outcome after AI failure, and are frequently detectable before clinical progression. Interventional studies based on ESR1 circulating status are warranted.

  12. Circulating ESR1 mutations at the end of aromatase inhibitor adjuvant treatment and after relapse in breast cancer patients.

    PubMed

    Allouchery, Violette; Beaussire, Ludivine; Perdrix, Anne; Sefrioui, David; Augusto, Laetitia; Guillemet, Cécile; Sarafan-Vasseur, Nasrin; Di Fiore, Frédéric; Clatot, Florian

    2018-05-16

    Detection of circulating ESR1 mutations is associated with acquired resistance to aromatase inhibitor (AI) in metastatic breast cancer. Until now, the presence of circulating ESR1 mutations at the end of adjuvant treatment by AI in early breast cancer had never been clearly established. In this context, the aim of the present study was to evaluate the circulating ESR1 mutation frequency at the end of adjuvant treatment and after relapse. This monocentric retrospective study was based on available stored plasmas and included all early breast cancer patients who completed at least 2 years of AI adjuvant treatment and experienced a documented relapse after the end of their treatment. Circulating ESR1 mutations (D538G, Y537S/N/C) were assessed by droplet digital PCR in plasma samples taken at the end of adjuvant treatment, at time of relapse and at time of progression under first line metastatic treatment. A total of 42 patients were included, with a median adjuvant AI exposure of 60 months (range 41-85). No circulating ESR1 mutation was detectable at the end of AI adjuvant therapy. At first relapse, 5.3% of the patients (2/38) had a detectable circulating ESR1 mutation. At time of progression on first-line metastatic treatment, 33% of the patients (7/21) under AI had a detectable circulating ESR1 mutation compared to none of the patients under chemotherapy (0/10). The two patients with a detectable ESR1 mutation at relapse were treated by AI and had an increase of their variant allele fraction at time of progression on first-line metastatic treatment. Circulating ESR1 mutation detection at the end of AI-based adjuvant treatment is not clinically useful. Circulating ESR1 mutation could be assessed as soon as first relapse to guide interventional studies.

  13. Genome-Wide Associations and Functional Genomic Studies of Musculoskeletal Adverse Events in Women Receiving Aromatase Inhibitors

    PubMed Central

    Ingle, James N.; Schaid, Daniel J.; Goss, Paul E.; Liu, Mohan; Mushiroda, Taisei; Chapman, Judy-Anne W.; Kubo, Michiaki; Jenkins, Gregory D.; Batzler, Anthony; Shepherd, Lois; Pater, Joseph; Wang, Liewei; Ellis, Matthew J.; Stearns, Vered; Rohrer, Daniel C.; Goetz, Matthew P.; Pritchard, Kathleen I.; Flockhart, David A.; Nakamura, Yusuke; Weinshilboum, Richard M.

    2010-01-01

    Purpose We performed a case-control genome-wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with musculoskeletal adverse events (MS-AEs) in women treated with aromatase inhibitors (AIs) for early breast cancer. Patients and Methods A nested case-control design was used to select patients enrolled onto the MA.27 phase III trial comparing anastrozole with exemestane. Cases were matched to two controls and were defined as patients with grade 3 or 4 MS-AEs (according to the National Cancer Institute's Common Terminology Criteria for Adverse Events v3.0) or those who discontinued treatment for any grade of MS-AE within the first 2 years. Genotyping was performed with the Illumina Human610-Quad BeadChip. Results The GWAS included 293 cases and 585 controls. A total of 551,358 SNPs were analyzed, followed by imputation and fine mapping of a region of interest on chromosome 14. Four SNPs on chromosome 14 had the lowest P values (2.23E-06 to 6.67E-07). T-cell leukemia 1A (TCL1A) was the gene closest (926-7000 bp) to the four SNPs. Functional genomic studies revealed that one of these SNPs (rs11849538) created an estrogen response element and that TCL1A expression was estrogen dependent, was associated with the variant SNP genotypes in estradiol-treated lymphoblastoid cells transfected with estrogen receptor alpha and was directly related to interleukin 17 receptor A (IL17RA) expression. Conclusion This GWAS identified SNPs associated with MS-AEs in women treated with AIs and with a gene (TCL1A) which, in turn, was related to a cytokine (IL17). These findings provide a focus for further research to identify patients at risk for MS-AEs and to explore the mechanisms for these adverse events. PMID:20876420

  14. Aromatase inhibitors associated musculoskeletal disorders and bone fractures in postmenopausal breast cancer patients: a result from Chinese population.

    PubMed

    Xu, Lu; Wang, Jue; Xue, Dan-Dan; He, Wei

    2014-09-01

    As the prognosis of early breast cancer patients improves, the long-term safety of aromatase inhibitors (AIs) is increasingly important. In the present study, we retrospectively investigated the incidences of musculoskeletal disorders (MSDs) and bone fractures in a cohort of Chinese postmenopausal patients with breast cancer. Data of postmenopausal patients with breast cancer were collected. Among which, 70 patients received AIs therapy (median follow-up of 32.5 months), 52 patients received tamoxifen (TAM), and 89 patients received no endocrine therapy (NE). Baseline characteristics, incidence of MSDs and bone fractures were analyzed and compared. When compared with NE group (40.4 %, 36/89), more patients in AIs group developed MSDs (72.9 %, 51/70, adjusted odds ratio (AOR) = 3.30, 95 % confidence interval (CI) = 1.59-6.88, P = 0.001). But no difference was found between TAM group (36.5 %, 19/52, AOR = 0.70, 95 % CI = 0.32-1.52, P = 0.372) and NE group. About 39.7 months after initial AIs therapy, nine patients in AI group developed bone fractures in different sites, and the bone fracture rate was significantly increased (12.9 %, 9/70, adjusted hazard ratio (AHR) = 20.08, 95 % CI = 1.72-234.08, P = 0.017) in comparison with NE group (1.1 %, 1/89). Moreover, the bone fracture rate of TAM group was not different from NE group (1.9 %, 1/52, AHR = 2.64, 95 % CI = 0.14-48.73, P = 0.513). AIs therapy may induce increased rates of MSDs and bone fractures in Chinese population of postmenopausal breast cancer patients, whereas TAM therapy did not help reduce the incidences of MSDs and bone fractures.

  15. Expression and Sequence Evolution of Aromatase cyp19a1 and Other Sexual Development Genes in East African Cichlid Fishes

    PubMed Central

    Böhne, Astrid; Heule, Corina; Boileau, Nicolas; Salzburger, Walter

    2013-01-01

    Sex determination mechanisms are highly variable across teleost fishes and sexual development is often plastic. Nevertheless, downstream factors establishing the two sexes are presumably conserved. Here, we study sequence evolution and gene expression of core genes of sexual development in a prime model system in evolutionary biology, the East African cichlid fishes. Using the available five cichlid genomes, we test for signs of positive selection in 28 genes including duplicates from the teleost whole-genome duplication, and examine the expression of these candidate genes in three cichlid species. We then focus on a particularly striking case, the A- and B-copies of the aromatase cyp19a1, and detect different evolutionary trajectories: cyp19a1A evolved under strong positive selection, whereas cyp19a1B remained conserved at the protein level, yet is subject to regulatory changes at its transcription start sites. Importantly, we find shifts in gene expression in both copies. Cyp19a1 is considered the most conserved ovary-factor in vertebrates, and in all teleosts investigated so far, cyp19a1A and cyp19a1B are expressed in ovaries and the brain, respectively. This is not the case in cichlids, where we find new expression patterns in two derived lineages: the A-copy gained a novel testis-function in the Ectodine lineage, whereas the B-copy is overexpressed in the testis of the speciest-richest cichlid group, the Haplochromini. This suggests that even key factors of sexual development, including the sex steroid pathway, are not conserved in fish, supporting the idea that flexibility in sexual determination and differentiation may be a driving force of speciation. PMID:23883521

  16. Impact of an osteoporosis specialized unit on bone health in breast cancer survivals treated with aromatase inhibitors.

    PubMed

    Martínez, Purificación; Galve, Elena; Arrazubi, Virginia; Sala, M Ángeles; Fernández, Seila; Pérez, Clara E; Arango, Juan F; Torre, Iñaki

    2017-10-11

    Considering the increased fracture risk in early breast cancer patients treated with aromatase inhibitors (AI), we assessed the impact of a preventive intervention conducted by a specialized osteoporosis unit on bone health at AI treatment start. Retrospective cohort of postmenopausal women who started treatment with AI after breast cancer surgical/chemotherapy treatment and were referred to the osteoporosis unit for a comprehensive assessment of bone health. Bone densitometry and fracture screening by plain X-ray were performed at the baseline visit and once a year for 5 years. The final record included 130 patients. At AI treatment start, 49% had at least one high-risk factor for fractures, 55% had osteopenia, and 39% osteoporosis. Based on the baseline assessment, 79% of patients initiated treatment with bisphosphonates, 88% with calcium, and 79% with vitamin D. After a median of 65 (50-77) months, 4% developed osteopenia or osteoporosis, and 14% improved their densitometric diagnosis. Fifteen fractures were recorded in 11 (8.5%) patients, all of them receiving preventive treatment (10 with bisphosphonates). During the follow-up period, patients with one or more high-risk factors for fracture showed a greater frequency of fractures (15% vs. 3%) and experienced the first fracture earlier than those without high-risk factors (mean of 99 and 102 months, respectively; P=0.023). The preventive intervention of a specialized unit at the start of AI treatment in breast cancer survivors allows the identification of patients with high fracture risk and may contribute to preventing bone events in these patients. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  17. Association between self-report adherence measures and oestrogen suppression among breast cancer survivors on aromatase inhibitors.

    PubMed

    Brier, Moriah J; Chambless, Dianne; Gross, Robert; Su, H Irene; DeMichele, Angela; Mao, Jun J

    2015-09-01

    Poor adherence to oral adjuvant hormonal therapy for breast cancer is a common problem, but little is known about the relationship between self-report adherence measures and hormonal suppression. We evaluated the relationship of three self-report measures of medication adherence and oestrogen among patients on aromatase inhibitors (AIs). We recruited 235 women with breast cancer who were prescribed AI therapy. Participants self-reported AI adherence by completing the following: (1) a single item asking whether they took an AI in the last month, (2) a modified Morisky Medication Adherence Scale-8 (MMAS-8) and (3) the Visual Analog Scale (VAS). Serum estrone and estradiol were analysed using organic solvent extraction and Celite column partition chromatography, followed by radioimmunoassay. Ten percent of participants reported they had not taken an AI in the last month and among this group, median estrone (33.2 pg/ml [interquartile range (IQR)=22.3]) and estradiol levels (7.2 pg/mL [IQR=3.3]) were significantly higher than those in participants who reported AI use (median estrone=11.5 pg/mL [IQR=4.9]; median estradiol=3.4 pg/mL [IQR=2.1]; p<0.001). This relationship held when controlling for race and AI drug type. A single-item monthly-recall adherence measure for AIs was associated with oestrogen serum levels. This suggests that patient-reported monthly adherence may be a useful measure to identify early non-adherence behaviour and guide interventions to improve patient adherence to hormonal treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. AROMATASE ACTIVITY IN THE OVARY OF MOSQUITOFISH GAMBUSIA HOLBROOKI, COLLECTED FROM THE FENHOLLOWAY AND ECONFINA RIVERS, FLORIDA (

    EPA Science Inventory

    Scientists are increasingly aware of the adverse effects of environmental contaminants, including their ability to alter the normal development and reproduction of wildlife species by modifying the endocrine system. Female mosquitofish living downstream of a paper mill plant loca...

  19. AROMATASE ACTIVITY IN THE OVARY AND BRAIN OF THE EASTERN MOSQUITOFISH, (GAMBUSIA HOLBROOKI) EXPOSED TO PAPER MILL EFFLUENT

    EPA Science Inventory

    Studies have shown that female mosquitofish living downstream of a paper mill located on the Fenholloway River, Florida, have masculinized secondary sex characteristics, including altered anal fin development and reproductive behavior. Masculinization can be caused by exposure to...

  20. A syndrome of female pseudohermaphrodism, hypergonadotropic hypogonadism, and multicystic ovaries associated with missense mutations in the gene encoding aromatase (P450arom).

    PubMed

    Conte, F A; Grumbach, M M; Ito, Y; Fisher, C R; Simpson, E R

    1994-06-01

    We report the features of a new syndrome of aromatase deficiency due to molecular defects in the CYP19 (P450arom) gene in a 46,XX female. At birth, the patient presented with a nonadrenal form of female pseudohermaphrodism. At 17 months of age, laparotomy revealed normal female internal genital structures; the histological appearance of the ovaries was normal. FSH concentrations were markedly elevated at 9.4 ng/mL LER 869, and estrone and estradiol levels were undetectable (< 37 pmol/L). By 14 yr of age, she had failed to exhibit breast development. The clitoris had enlarged to 4 x 2 cm, and pubic hair was Tanner stage IV. The plasma concentration of testosterone was elevated at 3294 pmol/L, as was androstenedione at 9951 pmol/L. Plasma estradiol levels were below 37 pmol/L. ACTH and dexamethasone tests indicated a nonadrenal source of testosterone and androstenedione. Plasma gonadotropin levels were in the castrate range. Pelvic sonography and magnetic resonance imaging showed multiple 4- to 6-cm ovarian cysts bilaterally. Despite increased circulating androgens and clitoral growth, the bone age was 10 yr at chronologic age 14 2/12 yr. Estrogen replacement therapy resulted in a growth spurt, breast development, menarche, suppression of gonadotropin levels, and resolution of the cysts. The clinical findings suggested the diagnosis of P450arom deficiency. Analyses of genomic DNA from ovarian fibroblasts demonstrated two single base changes in the coding region of the P450arom gene, one at 1303 basepairs (C-T), R435C, and the other at 1310 basepairs (G-A), C437Y, in exon 10. The molecular genetic studies indicate that the patient is a compound heterozygote for these mutations. Expression of these mutations showed that the R435C mutation had 1.1% the activity of the wild-type P450arom enzyme, whereas the C437Y mutation demonstrated no activity. The cardinal features of this syndrome are a consequence of P450arom deficiency: 1) the fetal masculinization in this

  1. Testosterone treatment increases androgen receptor and aromatase gene expression in myotubes from patients with PCOS and controls, but does not induce insulin resistance.

    PubMed

    Eriksen, Mette Brandt; Glintborg, Dorte; Nielsen, Michael Friberg Bruun; Jakobsen, Marianne Antonius; Brusgaard, Klaus; Tan, Qihua; Gaster, Michael

    2014-09-05

    Polycystic ovary syndrome (PCOS) is associated with insulin resistance and increased risk of type 2 diabetes. Skeletal muscle is the major site of insulin mediated glucose disposal and the skeletal muscle tissue is capable to synthesize, convert and degrade androgens. Insulin sensitivity is conserved in cultured myotubes (in vitro) from patients with PCOS, but the effect of testosterone on this insulin sensitivity is unknown. We investigated the effect of 7days testosterone treatment (100nmol/l) on glucose transport and gene expression levels of hormone receptors and enzymes involved in the synthesis and conversion of testosterone (HSD17B1, HSD17B2, CYP19A1, SRD5A1-2, AR, ER-α, HSD17B6 and AKR1-3) in myotubes from ten patients with PCOS and ten matched controls. Testosterone treatment significantly increased aromatase and androgen receptor gene expression levels in patients and controls. Glucose transport in myotubes was comparable in patients with PCOS vs. controls and was unchanged by testosterone treatment (p=0.21 PCOS vs. controls). These results suggest that testosterone treatment of myotubes increases the aromatase and androgen receptor gene expression without affecting insulin sensitivity and if testosterone is implicated in muscular insulin resistance in PCOS, this is by and indirect mechanism. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Adult height in patients with familial male-limited precocious puberty and the role of an aromatase inhibitor in patient management.

    PubMed

    Lane, Laura C; Flowers, Josephine; Johnstone, Helen; Cheetham, Tim

    2018-04-25

    There is little adult height data in patients with familial male-limited precocious puberty (FMPP) and no management consensus. We assessed the treatment and adult height in local patients with FMPP and those reported in the literature. Growth data were obtained on four local patients with FMPP and a search performed to obtain management details and adult height data on cases in the literature. UK (90) population standards were used to calculate standard deviation scores (SDS). Adult height data were available on 25 men with FMPP of whom 21 were treated. Median adult height SDS of patients was -1.5 SD with a mid-parental target of -0.6 SD (p=0.1). Eight patients (32%) had an adult height above the mid-parental target and seven patients (28%) had a height >2 SD below the mean. The median height SD was -0.03 in untreated patients and +0.5 SD in those receiving an aromatase inhibitor. There was no relationship between height and age at presentation. Aromatase inhibitor therapy is associated with a positive height outcome in FMPP but the outcome with and without intervention is unpredictable. Clinicians need to be cautious when counselling families about the potential height outcome in FMPP.

  3. Gene expression alterations associated with outcome in aromatase inhibitor-treated ER+ early-stage breast cancer patients.

    PubMed

    Thomsen, Karina G; Lyng, Maria B; Elias, Daniel; Vever, Henriette; Knoop, Ann S; Lykkesfeldt, Anne E; Lænkholm, Anne-Vibeke; Ditzel, Henrik J

    2015-12-01

    Aromatase inhibitors (AI), either alone or together with chemotherapy, have become the standard adjuvant treatment for postmenopausal, estrogen receptor-positive (ER+) breast cancer. Although AIs improve overall survival, resistance is still a major clinical problem, thus additional biomarkers predictive of outcome of ER+ breast cancer patients treated with AIs are needed. Global gene expression analysis was performed on ER+ primary breast cancers from patients treated with adjuvant AI monotherapy; half experienced recurrence (median follow-up 6.7 years). Gene expression alterations were validated by qRT-PCR, and functional studies evaluating the effect of siRNA-mediated gene knockdown on cell growth were performed. Twenty-six genes, including TFF3, DACH1, RGS5, and GHR, were shown to exhibit altered expression in tumors from patients with recurrence versus non-recurrent (fold change ≥1.5, p < 0.05), and the gene expression alterations were confirmed using qRT-PCR. Ten of these 26 genes could be linked in a network associated with cellular proliferation, growth, and development. TFF3, which encodes for trefoil factor 3 and is an estrogen-responsive oncogene shown to play a functional role in tamoxifen resistance and metastasis of ER+ breast cancer, was also shown to be upregulated in an AI-resistant cell line model, and reduction of TFF3 levels using TFF3-specific siRNAs decreased the growth of both the AI-resistant and -sensitive parental cell lines. Moreover, overexpression of TFF3 in parental AI-sensitive MCF-7/S0.5 cells resulted in reduced sensitivity to the AI exemestane, whereas TFF3 overexpression had no effect on growth in the absence of exemestane, indicating that TFF3 mediates growth and survival signals that abrogate the growth inhibitory effect of exemestane. We identified a panel of 26 genes exhibiting altered expression associated with disease recurrence in patients treated with adjuvant AI monotherapy, including TFF3, which was shown to

  4. Oral medications including clomiphene citrate or aromatase inhibitors with gonadotropins for controlled ovarian stimulation in women undergoing in vitro fertilisation.

    PubMed

    Kamath, Mohan S; Maheshwari, Abha; Bhattacharya, Siladitya; Lor, Kar Yee; Gibreel, Ahmed

    2017-11-02

    Gonadotropins are the most commonly used medications for controlled ovarian stimulation in in vitro fertilisation (IVF). However, they are expensive and invasive, and are associated with the risk of ovarian hyperstimulation syndrome (OHSS). Recent calls for more patient-friendly regimens have led to growing interest in the use of clomiphene citrate (CC) and aromatase inhibitors with or without gonadotropins to reduce the burden of hormonal injections. It is currently unknown whether regimens using CC or aromatase inhibitors such as letrozole (Ltz) are as effective as gonadotropins alone. To determine the effectiveness and safety of regimens including oral induction medication (such as clomiphene citrate or letrozole) versus gonadotropin-only regimens for controlled ovarian stimulation in IVF or intracytoplasmic sperm injection (ICSI) treatment. We searched the following databases: Cochrane Gynaecology and Fertility Group Specialised Register (searched January 2017), the Cochrane Central Register of Controlled Trials (CENTRAL CRSO), MEDLINE (1946 to January 2017), Embase (1980 to January 2017), and reference lists of relevant articles. We also searched trials registries ClinicalTrials.gov (clinicaltrials.gov/) and the World Health Organization International Clinical Trials Registry Platform (www.who.int/trialsearch/Default.aspx). We handsearched relevant conference proceedings. We included randomized controlled trials (RCTs). The primary outcomes were live-birth rate (LBR) and OHSS. Three review authors independently assessed trial eligibility and risk of bias. We calculated risk ratios (RR) and Peto odds ratio (OR) with 95% confidence intervals (CIs) for dichotomous outcomes and mean differences (MD) for continuous outcomes. We analyzed the general population of women undergoing IVF treatment and (as a separate analysis) women identified as poor responders. We assessed the overall quality of the evidence using the GRADE approach. We included 27 studies in the

  5. From molecule to behavior: Brain aromatase (cyp19a1b) characterization, expression analysis and its relation with social status and male agonistic behavior in a Neotropical cichlid fish.

    PubMed

    Ramallo, Martín R; Morandini, Leonel; Birba, Agustina; Somoza, Gustavo M; Pandolfi, Matías

    2017-03-01

    The enzyme aromatase, responsible for the conversion of C19 androgens to C18 estrogens, exists as two paralogue copies in teleost fish: Cyp19a1a mostly expressed in the gonads, referred as gonadal aromatase, and Cyp19a1b, mostly expressed in the brain, accordingly known as brain aromatase. The neural localization of Cyp19a1b is greatly contained within the social behavior network and mesolimbic reward system in fish, suggesting a strong role of estrogen synthesis in the regulation of social behavior. In this work we aimed to analyze the variation in cyp19a1b expression in brain and pituitary of males of a highly social cichlid, Cichlasoma dimerus (locally known as chanchita), and its relation with inter-individual variability in agonistic behavior in a communal social environment. We first characterized chanchita's cyp19a1b mRNA and deduced amino acid sequence, which showed a high degree of conservation when compared to other teleost brain aromatase sequences, and its tissue expression patterns. Within the brain, Cyp19a1b was solely detected at putative radial glial cells of the forebrain, close to the brain ventricles. We then studied the relative expression levels of cyp19a1b by Real Time PCR in the brain and pituitary of males of different social status, territorial vs. non-territorial, and its relationship with an index of agonistic behavior. We found that even though, brain aromatase expression did not differ between types of males, pituitary cyp19a1b expression levels positively correlated with the index of agonistic behavior. This suggests a novel role of the pituitary in the regulation of social behavior by local estrogen synthesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. A qualitative systematic review of the evidence base for non-cross-resistance between steroidal and non-steroidal aromatase inhibitors in metastatic breast cancer.

    PubMed

    Beresford, M; Tumur, I; Chakrabarti, J; Barden, J; Rao, N; Makris, A

    2011-04-01

    The most effective sequence of tamoxifen and both steroidal (SAIs) and non-steroidal aromatase inhibitors (NSAIs) has been extensively studied in the adjuvant setting. However, treatments for women who have failed initial aromatase inhibitor therapy in the metastatic setting have received relatively little attention. A systematic review was undertaken to assess the use of SAIs and NSAIs in metastatic breast cancer. Medline, Embase and the Cochrane library were searched using free text and MeSH terms. Studies assessing the cross-resistance, efficacy and safety of SAIs and NSAIs for postmenopausal women with advanced metastatic breast cancer confirmed by histology/cytology were included. Patients had progressed/relapsed from previous adjuvant, first- or second-line aromatase inhibitor treatment and had undergone treatment with at least two regimens consisting of aminoglutethimide, anastrozole, letrozole and/or exemestane. Nine studies reported results for patients treated with an SAI after treatment failure with an NSAI. For SAI after NSAI, clinical benefit was the most frequently reported outcome. The clinical benefit for exemestane (SAI) after any NSAI failure or before treatment ranged from 12% (complete response not recorded, partial response 2%, stable disease 10%) to 55% (complete response 6%, partial response 13%, stable disease 35%) Survival outcomes were infrequently reported; four studies reported disease progression. The time to progression ranged from 3.7 to 5.2 months. Only one study reported a median overall survival with exemestane at 15.2 months. Only one study reported information for an NSAI after SAI and an NSAI followed by another NSAI. This review suggests that switching from an NSAI to an SAI is a reasonable option. This would be particularly important for patients who would probably respond to further endocrine manoeuvres; strongly oestrogen receptor-positive disease, non-visceral disease, a good prior response or a long duration of response

  7. Treatment options in HR⁺/HER2⁻ advanced breast cancer patients pretreated with nonsteroidal aromatase inhibitors: what does current evidence tell us?

    PubMed

    De Placido, Sabino; Pronzato, Paolo

    2015-01-01

    Many postmenopausal women with advanced or metastatic breast cancer (BC) receive nonsteroidal aromatase inhibitors (NSAIs). Virtually all of them experience progression, but may still gain benefit from a different endocrine or targeted agent. We indirectly compare the results of trials on endocrine or targeted treatment in HR(+)/HER2(-) mBC patients who progressed after a prior NSAI therapy. Although with the limitations of any indirect comparison, evidence suggests that only the combination of everolimus and exemestane is associated with a prolonged progression-free survival and a more evident clinical benefit than its comparators. We speculate that prior NSAI therapy can 'per se' individuate patients eligible to everolimus. More robust data from head-to-head trials will provide more grounded evidence on this issue.

  8. Sex- and tissue-specific expression of P450 aromatase (cyp19a1a) in the yellowtail clownfish, Amphiprion clarkii.

    PubMed

    Kobayashi, Yasuhisa; Horiguchi, Ryo; Miura, Saori; Nakamura, Masaru

    2010-02-01

    To investigate the role of estrogen in the gonad of yellowtail clownfish Amphiprion clarkii, we isolated cDNA encoding cytochrome P450 aromatase (Cyp19a1a) from the adult ovary. The full-length cDNA of clownfish cyp19a1a is 1928-bp long and encodes 520 amino acids. Real-time quantitative RT-PCR analysis showed that cyp19a1a was expressed mainly in the ovary of female-phase fish. In situ hybridization and immunohistochemical observations showed that positive signals were restricted to the ovarian follicle of the female-phase fish. In contrast, Cyp19a1a signal was not detected in the ambisexual gonad of the male-phase fish. These findings suggest that Cyp19a1a is involved in oogenesis in the female-phase fish, but not in the ambisexual gonad of male-phase fish. 2009 Elsevier Inc. All rights reserved.

  9. Aromatase, steroid-5-alpha-reductase type 1 and type 2 mRNA expression in gonads and in brain of Xenopus laevis during ontogeny.

    PubMed

    Urbatzka, R; Lutz, I; Kloas, W

    2007-01-01

    The key enzymes involved in the production of endogenous sex steroids are steroid-5-alpha-reductase and aromatase converting testosterone (T) into dihydrotestosterone (DHT) and into estradiol (E2), respectively. To gain more insights into the molecular mechanisms of sexual differentiation of amphibians, we determined the mRNA expression of steroid-5-alpha-reductase type1 (Srd5a1), type2 (Srd5a2) and aromatase (Aro) during ontogeny starting from the egg and ending after completion of metamorphosis in Xenopus laevis. Expression of all three enzymes was measured by means of semi-quantitative RT-PCR, determining for the first time Srd5a1 and Srd5a2 mRNA expression in amphibians. mRNA was analyzed in whole body homogenates from stage 12 to 48, while brain and gonads with kidney were studied separately from stage 48 to 66. Different ontogenetic mRNA expression patterns were observed for all genes analyzed, revealing early mRNA expression of Srd5a1 already in the egg at stage 12 whereas Srd5a2 and Aro was detected at stage 39. Sex-specific mRNA expressions of Srd5a2 and of Aro were determined in the gonads with kidney but not in brain. Srd5a2 was two-fold higher expressed in testes than in ovaries while Aro mRNA was ten-fold higher in ovaries. No gender-specific mRNA expression was observed for Srd5a1 in gonads and in brain. The ontogenetic patterns of Aro, Srd5a1 and Srd5a2 suggest that these genes are involved in sexual differentiation of gonads and brain already in early developmental stages. Especially in gonads Srd5a2 seems to be important for physiological regulation of testis development while Aro is associated with the development of ovaries.

  10. A Systematic Review and Methodological Evaluation of Published Cost-Effectiveness Analyses of Aromatase Inhibitors versus Tamoxifen in Early Stage Breast Cancer

    PubMed Central

    John-Baptiste, Ava A.; Wu, Wei; Rochon, Paula; Anderson, Geoffrey M.; Bell, Chaim M.

    2013-01-01

    Background A key priority in developing policies for providing affordable cancer care is measuring the value for money of new therapies using cost-effectiveness analyses (CEAs). For CEA to be useful it should focus on relevant outcomes and include thorough investigation of uncertainty. Randomized controlled trials (RCTs) of five years of aromatase inhibitors (AI) versus five years of tamoxifen in the treatment of post-menopausal women with early stage breast cancer, show benefit of AI in terms of disease free survival (DFS) but not overall survival (OS) and indicate higher risk of fracture with AI. Policy-relevant CEA of AI versus tamoxifen should focus on OS and include analysis of uncertainty over key assumptions. Methods We conducted a systematic review of published CEAs comparing an AI to tamoxifen. We searched Ovid MEDLINE, EMBASE, PsychINFO, and the Cochrane Database of Systematic Reviews without language restrictions. We selected CEAs with outcomes expressed as cost per life year or cost per quality adjusted life year (QALY). We assessed quality using the Neumann checklist. Using structured forms two abstractors collected descriptive information, sources of data, baseline assumptions on effectiveness and adverse events, and recorded approaches to assessing parameter uncertainty, methodological uncertainty, and structural uncertainty. Results We identified 1,622 citations and 18 studies met inclusion criteria. All CE estimates assumed a survival benefit for aromatase inhibitors. Twelve studies performed sensitivity analysis on the risk of adverse events and 7 assumed no additional mortality risk with any adverse event. Sub-group analysis was limited; 6 studies examined older women, 2 examined women with low recurrence risk, and 1 examined women with multiple comorbidities. Conclusion Published CEAs comparing AIs to tamoxifen assumed an OS benefit though none has been shown in RCTs, leading to an overestimate of the cost-effectiveness of AIs. Results of these

  11. A systematic review and methodological evaluation of published cost-effectiveness analyses of aromatase inhibitors versus tamoxifen in early stage breast cancer.

    PubMed

    John-Baptiste, Ava A; Wu, Wei; Rochon, Paula; Anderson, Geoffrey M; Bell, Chaim M

    2013-01-01

    A key priority in developing policies for providing affordable cancer care is measuring the value for money of new therapies using cost-effectiveness analyses (CEAs). For CEA to be useful it should focus on relevant outcomes and include thorough investigation of uncertainty. Randomized controlled trials (RCTs) of five years of aromatase inhibitors (AI) versus five years of tamoxifen in the treatment of post-menopausal women with early stage breast cancer, show benefit of AI in terms of disease free survival (DFS) but not overall survival (OS) and indicate higher risk of fracture with AI. Policy-relevant CEA of AI versus tamoxifen should focus on OS and include analysis of uncertainty over key assumptions. We conducted a systematic review of published CEAs comparing an AI to tamoxifen. We searched Ovid MEDLINE, EMBASE, PsychINFO, and the Cochrane Database of Systematic Reviews without language restrictions. We selected CEAs with outcomes expressed as cost per life year or cost per quality adjusted life year (QALY). We assessed quality using the Neumann checklist. Using structured forms two abstractors collected descriptive information, sources of data, baseline assumptions on effectiveness and adverse events, and recorded approaches to assessing parameter uncertainty, methodological uncertainty, and structural uncertainty. We identified 1,622 citations and 18 studies met inclusion criteria. All CE estimates assumed a survival benefit for aromatase inhibitors. Twelve studies performed sensitivity analysis on the risk of adverse events and 7 assumed no additional mortality risk with any adverse event. Sub-group analysis was limited; 6 studies examined older women, 2 examined women with low recurrence risk, and 1 examined women with multiple comorbidities. Published CEAs comparing AIs to tamoxifen assumed an OS benefit though none has been shown in RCTs, leading to an overestimate of the cost-effectiveness of AIs. Results of these CEA analyses may be suboptimal for

  12. A polymorphism at the 3'-UTR region of the aromatase gene defines a subgroup of postmenopausal breast cancer patients with poor response to neoadjuvant letrozole

    PubMed Central

    2010-01-01

    Background Aromatase (CYP19A1) regulates estrogen biosynthesis. Polymorphisms in CYP19A1 have been related to the pathogenesis of breast cancer (BC). Inhibition of aromatase with letrozole constitutes the best option for treating estrogen-dependent BC in postmenopausal women. We evaluate a series of polymorphisms of CYP19A1 and their effect on response to neoadjuvant letrozole in early BC. Methods We analyzed 95 consecutive postmenopausal women with stage II-III ER/PgR [+] BC treated with neoadjuvant letrozole. Response to treatment was measured by radiology at 4th month by World Health Organization (WHO) criteria. Three polymorphisms of CYP19A1, one in exon 7 (rs700519) and two in the 3'-UTR region (rs10046 and rs4646) were evaluated on DNA obtained from peripheral blood. Results Thirty-five women (36.8%) achieved a radiological response to letrozole. The histopathological and immunohistochemical parameters, including hormonal receptor status, were not associated with the response to letrozole. Only the genetic variants (AC/AA) of the rs4646 polymorphism were associated with poor response to letrozole (p = 0.03). Eighteen patients (18.9%) reported a progression of the disease. Those patients carrying the genetic variants (AC/AA) of rs4646 presented a lower progression-free survival than the patients homozygous for the reference variant (p = 0.0686). This effect was especially significant in the group of elderly patients not operated after letrozole induction (p = 0.009). Conclusions Our study reveals that the rs4646 polymorphism identifies a subgroup of stage II-III ER/PgR [+] BC patients with poor response to neoadjuvant letrozole and poor prognosis. Testing for the rs4646 polymorphism could be a useful tool in order to orientate the treatment in elderly BC patients. PMID:20144226

  13. Localisation of epidermal growth factor (EGF), its specific receptor (EGF-R) and aromatase at the materno-fetal interface during placentation in the pregnant mare.

    PubMed

    Allen, W R Twink; Gower, Susan; Wilsher, Sandra

    2017-02-01

    Implantation and placentation in the mare does not commence until as late as day 40 after ovulation. The reasons for this and the growth factors and/or hormones which drive placentation when it does finally occur are of considerable academic and practical interest. Placental interface tissues recovered from 11 accurately aged and perfused-fixed horse uteri between 20 and 68 days of gestation were stained immunocytochemically for Epidermal Growth Factor (EGF), its specific receptor (EGF-R) and for the steroid hormone enzyme, aromatase. EGF was present in endometrial gland and lumenal epithelia from day 20 but staining intensity increased noticeably for the protein between days 30 and 40, coincidentally with the commencing secretion of equine Chorionic Gonadotrophin (eCG) from the endometrial cups and immediately prior to attachment and commencing interdigitation between the allantochorion and endometrium. EGF-R, on the other hand, was expressed strongly on the cell surface membrane of both non-invasive and invasive trophoblast and it similarly increased in staining intensity between days 30 and 40. Aromatase, the enzyme necessary for conversion of C-19 androgens to C-18 oestrogens, was expressed strongly and constantly from as early as day 12 in the non-invasive trophoblast of the allantochorion, but not the invasive trophoblast of the chorionic girdle, the progenitor tissue of the endometrial cups. The findings support the hypothesis that, in equine pregnancy, the maternal growth factor EGF synergises with maternally and fetally secreted oestrogens to drive the rapid growth and extensive vascularisation of the non-invasive, epitheliochorial, microcotyledonary placenta which results in the birth of the precocious foal after only 11 months gestation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Germline variants in the CYP19A1 gene are related to specific adverse events in aromatase inhibitor users: a substudy of Dutch patients in the TEAM trial.

    PubMed

    Fontein, Duveken B Y; Houtsma, Daniel; Nortier, Johan W R; Baak-Pablo, Renee F; Kranenbarg, Elma Meershoek-Klein; van der Straaten, Tahar R J H M; Putter, Hein; Seynaeve, Caroline; Gelderblom, Hans; van de Velde, Cornelis J H; Guchelaar, Henk-Jan

    2014-04-01

    Musculoskeletal adverse events (MSAEs) and vasomotor symptoms (VMSs) are known side-effects of aromatase inhibitors, and may be related to genetic variations of the aromatase gene (CYP19A1). We investigated the relationship between these specific AEs and single nucleotide polymorphisms (SNPs) in the CYP19A1 gene in postmenopausal, hormone receptor-positive early breast cancer (BC) patients treated with adjuvant exemestane for 5 years. Dutch patients who were randomized to receive 5 years of exemestane in the Tamoxifen Exemestane Adjuvant Multinational (TEAM) trial were included. A tagging-SNP approach was performed, covering 80 % of variations of the CYP19A1 gene with 30 SNPs. Logistic regression analyses were used to assess the risk of reporting VMSs or MSAEs in relation to genotypes within selected SNPs. Of 737 included patients, 281 patients reported at least one MSAE (n = 210) or VMS (n = 163). Homozygous AA genotype of rs934635 was associated with a significantly higher odds of MSAEs (multivariate odds ratio (OR) 4.66, p = 0.008) and VMSs (multivariate OR 2.78, p = 0.044). Regarding both rs1694189 and rs7176005, the homozygous variant genotypes (TT) were associated with a higher odds of VMSs, but not MSAEs (OR 1.758, p = 0.025 and OR 6.361, p = 0.021, respectively). Our exploratory analysis demonstrated that some CYP19A1 gene variations may be associated with MSAEs and/or VMSs. Specifically, patients with the homozygous variant rs934635 genotype reported more MSAEs and VMSs. Although further confirmatory studies are warranted, genomic profiling can help identify patients at an increased risk of reporting these specific AEs, potentiating further personalized BC treatment.

  15. Complementary or alternative medicine as possible determinant of decreased persistence to aromatase inhibitor therapy among older women with non-metastatic breast cancer.

    PubMed

    Huiart, Laetitia; Bouhnik, Anne-Deborah; Rey, Dominique; Rousseau, Frédérique; Retornaz, Frédérique; Meresse, Mégane; Bendiane, Marc Karim; Viens, Patrice; Giorgi, Roch

    2013-01-01

    Aromatase inhibitor therapy (AI) significantly improves survival in breast cancer patients. Little is known about adherence and persistence to aromatase inhibitors and about the causes of treatment discontinuation among older women. We constituted a cohort of women over 65 receiving a first AI therapy for breast cancer between 2006 and 2008, and followed them until June 2011. Women were selected in the population-based French National Health Insurance databases, and data was collected on the basis of pharmacy refills, medical records and face-to-face interviews. Non-persistence to treatment was defined as the first treatment discontinuation lasting more than 3 consecutive months. Time to treatment discontinuation was studied using survival analysis techniques. Overall among the 382 selected women, non-persistence to treatment went from 8.7% (95%CI: 6.2-12.1) at 1 year, to 15.6% (95%CI: 12.2-19.8) at 2 years, 20.8% (95%CI: 16.7-25.6) at 3 years, and 24.7% (95%CI: 19.5-31.0) at 4 years. In the multivariate analysis on a sub-sample of 233 women with available data, women using complementary or alternative medicine (CAM) (HR = 3.2; 95%CI: 1.5-6.9) or suffering from comorbidities (HR = 2.2; 95%CI: 1.0-4.8) were more likely to discontinue their treatment, whereas women with polypharmacy (HR = 0.4; 95%CI: 0.2-0.91) were less likely to discontinue. In addition, 13% of the women with positive hormonal receptor status did not fill any prescription for anti-hormonal therapy. AI therapy is discontinued prematurely in a substantial portion of older patients. Some patients may use CAM not as a complementary treatment, but as an alternative to conventional medicine. Improving patient-physician communication on the use of CAM may improve hormonal therapy adherence.

  16. Characterization and expression profile of the ovarian cytochrome P-450 aromatase (cyp19A1) gene during thermolabile sex determination in Pejerrey, Odontesthes bonariensis

    USGS Publications Warehouse

    Karube, M.; Fernandino, J.I.; Strobl-Mazzulla, P.; Strussmann, C.A.; Yoshizaki, G.; Somoza, G.M.; Patino, R.

    2007-01-01

    Cytochrome P450 aromatase (cyp19) is an enzyme that catalyzes the conversion of androgens to estrogens and may play a role in temperature- dependent sex determination (TSD) of reptiles, amphibians, and fishes. In this study, the ovarian P450 aromatase form (cyp19A1) of pejerrey Odontesthes bonariensis, a teleost with marked TSD, was cloned and its expression profile evaluated during gonadal differentiation at feminizing (17??C, 100% females), mixed-sex producing (24 and 25??C, 73.3 and 26.7% females, respectively), and masculinizing (29??C, 0% females) temperatures. The deduced cyp19A1 amino acid sequence shared high identity (>77.8%) with that from other teleosts but had low identity (<61.8%) with brain forms (cyp19A2), including that of pejerrey itself. The tissue distribution analysis of cyp19A1 mRNA in adult fish revealed high expression in the ovary. Semi-quantitative reverse transcription polymerase chain reaction analysis of the bodies of larvae revealed that cyp19A1 expression increased before the appearance of the first histological signs of ovarian differentiation at the feminizing temperature but remained low at the masculinizing temperature. The expression levels at mixed-sex producing temperatures were bimodal rather than intermediate, showing low and high modal values similar to those at the feminizing and masculinizing temperatures, respectively. The population percentages of high and low expression levels at intermediate temperatures were proportional to the percentage of females and males, respectively, and high levels were first observed at about the time of sex differentiation of females. These results suggest that cyp19A1 is involved in the process of ovarian formation and possibly also in the TSD of pejerrey. ?? 2007 Wiley-Liss, Inc.

  17. Anti-GD2-ch14.18/CHO coated nanoparticles mediate glioblastoma (GBM)-specific delivery of the aromatase inhibitor, Letrozole, reducing proliferation, migration and chemoresistance in patient-derived GBM tumor cells.

    PubMed

    Tivnan, Amanda; Heilinger, Tatjana; Ramsey, Joanne M; O'Connor, Gemma; Pokorny, Jenny L; Sarkaria, Jann N; Stringer, Brett W; Day, Bryan W; Boyd, Andrew W; Kim, Ella L; Lode, Holger N; Cryan, Sally-Ann; Prehn, Jochen H M

    2017-03-07

    Aromatase is a critical enzyme in the irreversible conversion of androgens to oestrogens, with inhibition used clinically in hormone-dependent malignancies. We tested the hypothesis that targeted aromatase inhibition in an aggressive brain cancer called glioblastoma (GBM) may represent a new treatment strategy. In this study, aromatase inhibition was achieved using third generation inhibitor, Letrozole, encapsulated within the core of biodegradable poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs). PLGA-NPs were conjugated to human/mouse chimeric anti-GD2 antibody ch14.18/CHO, enabling specific targeting of GD2-positive GBM cells. Treatment of primary and recurrent patient-derived GBM cells with free-Letrozole (0.1 μM) led to significant decrease in cell proliferation and migration; in addition to reduced spheroid formation. Anti-GD2-ch14.18/CHO-NPs displayed specific targeting of GBM cells in colorectal-glioblastoma co-culture, with subsequent reduction in GBM cell numbers when treated with anti-GD2-ch14.18-PLGA-Let-NPs in combination with temozolomide. As miR-191 is an estrogen responsive microRNA, its expression, fluctuation and role in Letrozole treated GBM cells was evaluated, where treatment with premiR-191 was capable of rescuing the reduced proliferative phenotype induced by aromatase inhibitor. The repurposing and targeted delivery of Letrozole for the treatment of GBM, with the potential role of miR-191 identified, provides novel avenues for target assessment in this aggressive brain cancer.

  18. Anti-GD2-ch14.18/CHO coated nanoparticles mediate glioblastoma (GBM)-specific delivery of the aromatase inhibitor, Letrozole, reducing proliferation, migration and chemoresistance in patient-derived GBM tumor cells

    PubMed Central

    Tivnan, Amanda; Heilinger, Tatjana; Ramsey, Joanne M; O’Connor, Gemma; Pokorny, Jenny L; Sarkaria, Jann N; Stringer, Brett W; Day, Bryan W; Boyd, Andrew W; Kim, Ella L; Lode, Holger N; Cryan, Sally-Ann; Prehn, Jochen H.M

    2017-01-01

    Aromatase is a critical enzyme in the irreversible conversion of androgens to oestrogens, with inhibition used clinically in hormone-dependent malignancies. We tested the hypothesis that targeted aromatase inhibition in an aggressive brain cancer called glioblastoma (GBM) may represent a new treatment strategy. In this study, aromatase inhibition was achieved using third generation inhibitor, Letrozole, encapsulated within the core of biodegradable poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs). PLGA-NPs were conjugated to human/mouse chimeric anti-GD2 antibody ch14.18/CHO, enabling specific targeting of GD2-positive GBM cells. Treatment of primary and recurrent patient-derived GBM cells with free-Letrozole (0.1 μM) led to significant decrease in cell proliferation and migration; in addition to reduced spheroid formation. Anti-GD2-ch14.18/CHO-NPs displayed specific targeting of GBM cells in colorectal-glioblastoma co-culture, with subsequent reduction in GBM cell numbers when treated with anti-GD2-ch14.18-PLGA-Let-NPs in combination with temozolomide. As miR-191 is an estrogen responsive microRNA, its expression, fluctuation and role in Letrozole treated GBM cells was evaluated, where treatment with premiR-191 was capable of rescuing the reduced proliferative phenotype induced by aromatase inhibitor. The repurposing and targeted delivery of Letrozole for the treatment of GBM, with the potential role of miR-191 identified, provides novel avenues for target assessment in this aggressive brain cancer. PMID:28178667

  19. Bisphenol A differentially activates protein kinase C isoforms in murine placental tissue

    SciTech Connect

    Tan, Wenjuan; Huang, Hui; Wang, Yanfei

    2013-06-01

    Bisphenol A is utilized to make polycarbonate plastics and is an environmental pollutant. Recent research has indicated that it is an endocrine disruptor and may interfere with reproductive processes. Our lab has previously shown that bisphenol A could regulate corticotrophin releasing hormone and aromatase in cultured placental cells. In the present study, the effect of bisphenol A on these two genes in the placenta was investigated in mice. Pregnant ICR mice were gavaged with bisphenol A at 2, 20 and 200 mg/kg body weight/day from E13 to E16 and were euthanized at E17. Compared to the control mice, increased plasmamore » estrogen and corticotrophin releasing hormone were observed in bisphenol A-treated mice. Messenger RNA quantification indicated that placental crh but not cyp19 was induced in mice treated with bisphenol A. Tracking the related signaling pathway, we found that protein kinase C ζ/λ and δ were activated in the placentas of bisphenol A-treated mice. As the gene promoter of crh contains CRE and the half site of ERE, either phospho-PKC or estrogen could stimulate the gene transactivation. These results indicate that bisphenol A might increase plasma concentrations of estradiol, testosterone, corticotrophin releasing hormone and placental phospho-PKC ζ/λ and δ in mice. Ultimately, the incidence of premature birth in these mice could increase. - Highlights: • The pollutant bisphenol A differentially activated PKC isoforms in the placenta. • CRE-binding activity in the nuclear protein of placenta was increased. • Bisphenol A induces CRH mRNA expression in mice.« less

  20. Additive effects of levonorgestrel and ethinylestradiol on brain aromatase (cyp19a1b) in zebrafish specific in vitro and in vivo bioassays

    SciTech Connect

    Hinfray, N., E-mail: nathalie.hinfray@ineris.fr

    Estrogens and progestins are widely used in combination in human medicine and both are present in aquatic environment. Despite the joint exposure of aquatic wildlife to estrogens and progestins, very little information is available on their combined effects. In the present study we investigated the effect of ethinylestradiol (EE2) and Levonorgestrel (LNG), alone and in mixtures, on the expression of the brain specific ER-regulated cyp19a1b gene. For that purpose, recently established zebrafish-derived tools were used: (i) an in vitro transient reporter gene assay in a human glial cell line (U251-MG) co-transfected with zebrafish estrogen receptors (zfERs) and the luciferase genemore » under the control of the zebrafish cyp19a1b gene promoter and (ii) an in vivo bioassay using a transgenic zebrafish expressing GFP under the control of the zebrafish cyp19a1b gene promoter (cyp19a1b-GFP). Concentration-response relationships for single chemicals were modeled and used to design the mixture experiments following a ray design. The results from mixture experiments were analyzed to predict joint effects according to concentration addition and statistical approaches were used to characterize the potential interactions between the components of the mixtures (synergism/antagonism). We confirmed that some progestins could elicit estrogenic effects in fish brain. In mixtures, EE2 and LNG exerted additive estrogenic effects both in vitro and in vivo, suggesting that some environmental progestin could exert effects that will add to those of environmental (xeno-)estrogens. Moreover, our zebrafish specific assays are valuable tools that could be used in risk assessment for both single chemicals and their mixtures. - Highlights: • Combined effects of EE2 and LNG were assessed on ER-dependent cyp19a1b expression. • EE2 and LNG alone induced brain aromatase in zebrafish specific bioassays. • Experimental ray design allowed complete concentration-response surfaces modeling.

  1. Complementary or Alternative Medicine as Possible Determinant of Decreased Persistence to Aromatase Inhibitor Therapy among Older Women with Non-Metastatic Breast Cancer

    PubMed Central

    Huiart, Laetitia; Bouhnik, Anne-Deborah; Rey, Dominique; Rousseau, Frédérique; Retornaz, Frédérique; Meresse, Mégane; Bendiane, Marc Karim; Viens, Patrice; Giorgi, Roch

    2013-01-01

    Purpose Aromatase inhibitor therapy (AI) significantly improves survival in breast cancer patients. Little is known about adherence and persistence to aromatase inhibitors and about the causes of treatment discontinuation among older women. Methods We constituted a cohort of women over 65 receiving a first AI therapy for breast cancer between 2006 and 2008, and followed them until June 2011. Women were selected in the population-based French National Health Insurance databases, and data was collected on the basis of pharmacy refills, medical records and face-to-face interviews. Non-persistence to treatment was defined as the first treatment discontinuation lasting more than 3 consecutive months. Time to treatment discontinuation was studied using survival analysis techniques. Results Overall among the 382 selected women, non-persistence to treatment went from 8.7% (95%CI: 6.2–12.1) at 1 year, to 15.6% (95%CI: 12.2–19.8) at 2 years, 20.8% (95%CI: 16.7–25.6) at 3 years, and 24.7% (95%CI: 19.5–31.0) at 4 years. In the multivariate analysis on a sub-sample of 233 women with available data, women using complementary or alternative medicine (CAM) (HR = 3.2; 95%CI: 1.5–6.9) or suffering from comorbidities (HR = 2.2; 95%CI: 1.0–4.8) were more likely to discontinue their treatment, whereas women with polypharmacy (HR = 0.4; 95%CI: 0.2–0.91) were less likely to discontinue. In addition, 13% of the women with positive hormonal receptor status did not fill any prescription for anti-hormonal therapy. Conclusion AI therapy is discontinued prematurely in a substantial portion of older patients. Some patients may use CAM not as a complementary treatment, but as an alternative to conventional medicine. Improving patient-physician communication on the use of CAM may improve hormonal therapy adherence. PMID:24367488

  2. Hypothalamic-pituitary-ovarian axis during infancy, early and late prepuberty in an aromatase-deficient girl who is a compound heterocygote for two new point mutations of the CYP19 gene.

    PubMed

    Belgorosky, Alicia; Pepe, Carolina; Marino, Roxana; Guercio, Gabriela; Saraco, Nora; Vaiani, Elisa; Rivarola, Marco A

    2003-11-01

    A loss of function mutation of the CYP19 aromatase gene leads to excess circulating androgens in the fetus and in the mother, resulting in ambiguous genitalia in the female fetus. Later on, lack of aromatase is responsible for sexual infantilism, primary amenorrhea, tall stature, and multicystic ovaries, even in preadolescent girls. Up to now, 11 CYP19 aromatase point mutations and 10 well-documented cases have been reported. In the present case, we are reporting the clinical and hormonal follow-up, from birth to 7 yr of age, of an affected girl with ambiguous genitalia. Gene analysis showed that she was a compound heterozygote for two new CYP19 aromatase point mutations. In the father's allele, there was a consensus 5' splice donor sequence mutation, GAA-AAA at cDNA position bp 655 in exon 5, which probably results in a cryptic donor site. In the mother's allele, there was a base A deletion in exon 9 (Delta A GLU 412X), causing a frame shift mutation, and a stop codon after 98 bp (33 codons) downstream, altering the critical heme-binding region. Basal serum LH and FSH levels were high at 8 d of age (42.9 and 51.3 U/liter), 26 d of age (76.2 and 119 U/liter), and 60 d of age (58.7 and 150 U/liter, respectively). Both gonadotropins dropped dramatically between the second and fifth months of age (to 1.79 and 14.9 U/liter) but remained higher than in normal control girls (0.64 and 8.5 U/liter, respectively). Serum testosterone (T) and androstenedione (Delta(4)A) levels were high during the first month, but Delta(4)A was normal at 2 months of age. However, at 5 months of age, along with significant decrements of serum LH and FSH levels and increments in serum Delta(4)A and T levels, a large ovarian cyst was removed from each gonad. Relatively high levels of T [27.3 ng/ml (94.6 nmol/liter); control, 34.9 ng/ml (121 nmol/liter)], but not of estradiol [1.8 ng/ml (6.6 nmol/liter); control 62.9 ng/ml (231 nmol/liter)], and a high T/estradiol ratio [15.2; control < 1] were

  3. The efficacy of bisphosphonates in preventing aromatase inhibitor induced bone loss for postmenopausal women with early breast cancer: a systematic review and meta-analysis.

    PubMed

    Anagha, Pooleriveetil Padikkal; Sen, Suchandra

    2014-01-01

    Objectives. We aim to determine the efficacy of bisphosphonates in preventing aromatase inhibitor induced bone loss (AIBL) in postmenopausal women with early breast cancer. The secondary objective was to determine the safety of bisphosphonates. Materials and Methods. We searched electronic databases in a time period of 1995 January to 2013 June. Random effects meta-analytical models were used; between study heterogeneity and publication bias was assessed. Results. A total of six eligible studies reported the BMD T score of LS at 12 months and from that 3 trials of Zoledronic acid compared the change in BMD in immediate ZOL versus delayed ZOL done with subgroups like patients with normal BMD at baseline (OR = 5.402, 95% CI = 1.329-21.959, P value = 0.018) and osteopenic BMD at baseline (OR = 4.008, 95% CI = 2.249-7.143, P value = 0.0002). Both had a significant decrease in BMD that favoured the delayed ZOL; 3 trials of risedronate and ibandronate also had a significant decrease in BMD in AIs alone group. Immediate ZOL versus delayed ZOL also showed increased risk of getting an ADR in immediate group. Conclusion. Third generation bisphosphonates has an effect on BMD of patients who are on treatment of AIs in breast cancer. Furthermore, the patients treated with immediate ZOL had a significantly high risk of musculoskeletal ADR's than patients with delayed ZOL.

  4. Serum leptin level and waist-to-hip ratio (WHR) predict the overall survival of metastatic breast cancer (MBC) patients treated with aromatase inhibitors (AIs).

    PubMed

    Artac, Mehmet; Bozcuk, Hakan; Kiyici, Aysel; Eren, Orhan Onder; Boruban, Melih Cem; Ozdogan, Mustafa

    2013-04-01

    Our objective was to determine whether serum leptin levels and obesity-related factors could affect outcome for metastatic breast cancer (MBC) patients treated with aromatase inhibitors (AIs). Sixty MBC patients treated with first line hormonal therapy were enrolled in this study. Median age was 51 years (range 28-75). Median leptin level was 19400 pg/ml (1970-91900) and estradiol level 29.6 pg/ml (4.0-181.9). Factors associated with overall survival in univariate analysis were age and waist-to-hip ratio (WHR), whereas only WHR retained significance in the multivariate analysis. However, no factor was associated with progression-free survival. However, WHR was found to be a significant prognostic marker only if the leptin level was ≥19400 pg/ml (HR = 0.38; 95% CI: 0.16-0.91). This study suggests that serum leptin levels and WHR together may serve as potential prognostic markers in MBC patients treated with AIs.

  5. Serum estradiol should be monitored not only during the peri-menopausal period but also the post-menopausal period at the time of aromatase inhibitor administration

    PubMed Central

    2009-01-01

    Background Aromatase inhibitor (AI) therapy is being extensively used as postoperative adjuvant therapy in patients with hormone receptor-positive postmenopausal breast cancer. On the other hand, it has been reported that ovarian function was restored when AI was administered to patients who had undergone chemical menopause with chemotherapy or tamoxifen. However, there have been no reports of comprehensive monitoring of estradiol (E2) in breast cancer patients with ordinary menopause who were being administered AI. Patients and Methods Beginning in March 2008, regular monitoring of the serum levels of E2, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) was performed for 66 postmenopausal breast cancer patients who had been started on AI therapy. For this study, we chose anastrozole as the AI. The assays of those hormones were outsourced to a commercial clinical laboratory. Results In 4 of the 66 patients the serum E2 level was decreased at 3 months but had then increased at 6 months, while in 2 other patients E2 was decreased at both 3 and 6 months but had increased at 9 months. Conclusion The results indicate that, in some breast cancer patients with ordinary menopause, E2 rebounds following AI therapy. In the future, E2 monitoring should be performed for a larger number of patients being administered AI therapy. Trial registration Our trial registration number is 19-11-1211. PMID:19909552

  6. Methodological issues in evaluating cost effectiveness of adjuvant aromatase inhibitors in early breast cancer: a need for improved modelling to aid decision making.

    PubMed

    Annemans, Lieven

    2008-01-01

    The optimal adjuvant hormonal strategy in post-menopausal women with early breast cancer is a subject of ongoing debate. Aromatase inhibitors (AIs) have been successfully evaluated in clinical trials that have compared them with a standard treatment of 5 years of tamoxifen. However, several options are available in terms of treatment schedule and selected drug. Systematic reviews of clinical trials and health economic evaluations attempt to contribute to the debate. The objective of this paper is to provide a critical review of existing health economic evaluations with a focus on those parameters and assumptions with the largest impact on final outcomes.A wide range of different inputs and assumptions exist, which make a comparison of results difficult, if not impossible. In particular, the modelling of recurrence rates over longer time horizons than those observed in clinical trials, a cornerstone of health economic modelling, is subject to quite different approaches. The practice of indirect comparison of different AIs without sufficiently acknowledging population differences is also bothersome. A list of key features (related to time horizon, clinical data input, patient subtypes, budget impact and model calibration) that an ideal model should have in order to better assist decision makers in this field is proposed.

  7. Mitogenic activity of a water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii. IV. Synergistic effects of Bu-WSA on Concanavalin A-induced proliferative response of human peripheral blood lymphocytes.

    PubMed

    Nitta, T; Okumura, S; Tsushi, M; Nakano, M

    1982-01-01

    Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens.

  8. Mitogenic Activity of a Water-Soluble Adjuvant (Bu-WSA) Obtained from Bacterionema matruchotii: IV. Synergistic Effects of Bu-WSA on Concanavalin A-Induced Proliferative Response of Human Peripheral Blood Lymphocytes.

    PubMed

    Nitta, Toshimasa; Okumura, Seiichi; Tsushi, Masao; Nakano, Masayasu

    1982-07-01

    Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens. © owned by Center for Academic Publications Japan (Publisher).

  9. In vitro - in vivo correlations for endocrine activity of a mixture of currently used pesticides

    SciTech Connect

    Taxvig, Camilla, E-mail: camta@food.dtu.dk; Hadrup, Niels; Boberg, Julie

    Two pesticide mixtures were investigated for potential endocrine activity. Mix 3 consisted of bitertanol, propiconazole, and cypermethrin, and Mix 5 included malathion and terbuthylazine in addition to the three pesticides in Mix 3. All five single pesticides and the two mixtures were investigated for their ability to affect steroidogenesis in vitro in H295R cells. The pesticides alone and both mixtures affected steroidogenesis with both mixtures causing increase in progesterone and decrease in testosterone. For Mix 5 an increase in estradiol was seen as well, indicating increased aromatase activity. The two mixtures were also investigated in pregnant rats dosed from gestationalmore » day 7 to 21, followed by examination of dams and fetuses. Decreased estradiol and reduced placental testosterone were seen in dams exposed to Mix 5. Also a significant increase in aromatase mRNA-levels in female adrenal glands was found for Mix5. However, either of the two mixtures showed any effects on fetal hormone levels in plasma or testis, or on anogenital distance. Overall, potential aromatase induction was found for Mix 5 both in vitro and in vivo, but not for Mix 3, an effect likely owed to terbuthylazine in Mix 5. However, the hormonal responses in vitro were only partly reflected in vivo, probably due to some toxicokinetic issues, as the pesticide levels in the amniotic fluid also were found to be negatively affected by the number of compounds present in the mixtures. Nonetheless, the H295R assay gives hints on conceivable interference with steroidogenesis, thus generating hypotheses on in vivo effects. - Highlights: • The study examines the endocrine disrupting potential of mixtures of pesticides. • All single pesticides and both mixtures affected steroidogenesis in vitro. • Potential aromatase induction was found for Mix 5 both in vitro and in vivo. • The hormonal responses in vitro were only partly reflected in vivo.« less

  10. Protection against ultraviolet A-induced oxidative damage in normal human epidermal keratinocytes under post-menopausal conditions by an ultraviolet A-activated caged-iron chelator: a pilot study.

    PubMed

    Pelle, Edward; Jian, Jinlong; Declercq, Lieve; Dong, Kelly; Yang, Qing; Pourzand, Charareh; Maes, Daniel; Pernodet, Nadine; Yarosh, Daniel B; Huang, Xi

    2011-10-01

    Human skin is constantly exposed to ultraviolet A (UVA), which can generate reactive oxygen species and cause iron release from ferritin, leading to oxidative damage in biomolecules. This is particularly true in post-menopausal skin due to an increase in iron as a result of menopause. As iron is generally released through desquamation, the skin becomes a main portal for the release of excess iron in this age group. In the present study, we examined a strategy for controlling UVA- and iron-induced oxidative stress in skin using a keratinocyte post-menopausal cellular model system. Keratinocytes that had been cultured under normal or high-iron, low-estrogen conditions were treated with (2-nitrophenyl) ethyl pyridoxal isonicotinoyl hydrazone (2-PNE-PIH). 2-PNE-PIH is a caged-iron chelator that does not normally bind iron but can be activated by UVA radiation to bind iron. Following incubation with 2-PNE-PIH, the cells were exposed to 5 J/cm² UVA and then measured for changes in lipid peroxidation and ferritin levels. 2-PNE-PIH protected keratinocytes against UVA-induced lipid peroxidation and ferritin depletion. Further, 2-PNE-PIH was neither cytotoxic nor did it alter iron metabolism. 2-PNE-PIH may be a useful deterrent against UVA-induced oxidative stress in post-menopausal women. © 2011 John Wiley & Sons A/S.

  11. Artificial masculinization in tilapia involves androgen receptor activation.

    PubMed

    Golan, Matan; Levavi-Sivan, Berta

    2014-10-01

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

  12. Chronic treatment with polychlorinated biphenyls (PCB) during pregnancy and lactation in the rat Part 2: Effects on reproductive parameters, on sex behavior, on memory retention and on hypothalamic expression of aromatase and 5alpha-reductases in the offspring.

    PubMed

    Colciago, A; Casati, L; Mornati, O; Vergoni, A V; Santagostino, A; Celotti, F; Negri-Cesi, P

    2009-08-15

    The gender-specific expression pattern of aromatase and 5alpha-reductases (5alpha-R) during brain development provides neurons the right amount of estradiol and DHT to induce a dimorphic organization of the structure. Polychlorinated biphenyls (PCBs) are endocrine disruptive pollutants; exposure to PCBs through placental transfer and breast-feeding may adversely affect the organizational action of sex steroid, resulting in long-term alteration of reproductive neuroendocrinology. The study was aimed at: a) evaluating the hypothalamic expression of aromatase, 5alpha-R1 and 5alpha-R2 in fetuses (GD20), infant (PN12), weaning (PN21) and young adult (PN60) male and female rats exposed to PCBs during development; b) correlating these parameters with the time of testicular descent, puberty onset, estrous cyclicity and copulatory behavior; c) evaluating possible alterations of some non reproductive behaviors (locomotion, learning and memory, depression/anxiety behavior). A reconstituted mixture of four indicator congeners (PCB 126, 138, 153 and 180) was injected subcutaneously to dams at the dose of 10 mg/kg daily from GD15 to GD19 and then twice a week till weanling. The results indicated that developmental PCB exposure produced important changes in the dimorphic hypothalamic expression of both aromatase and the 5alpha-Rs, which were still evident in adult animals. We observed that female puberty onset occurs earlier than in control animals without cycle irregularity, while testicular descent in males was delayed. A slight but significant impairment of sexual behavior and an important alteration in memory retention were also noted specifically in males. We conclude that PCBs might affect the dimorphic neuroendocrine control of reproductive system and of other neurobiological processes.

  13. Comparison of tamoxifen and letrozole response in mammary preneoplasia of ER and aromatase overexpressing mice defines an immune-associated gene signature linked to tamoxifen resistance

    PubMed Central

    Dabydeen, Sarah A.; Kang, Keunsoo; Díaz-Cruz, Edgar S.; Alamri, Ahmad; Axelrod, Margaret L.; Bouker, Kerrie B.; Al-Kharboosh, Rawan; Clarke, Robert; Hennighausen, Lothar; Furth, Priscilla A.

    2015-01-01

    Response to breast cancer chemoprevention can depend upon host genetic makeup and initiating events leading up to preneoplasia. Increased expression of aromatase and estrogen receptor (ER) is found in conjunction with breast cancer. To investigate response or resistance to endocrine therapy, mice with targeted overexpression of Esr1 or CYP19A1 to mammary epithelial cells were employed, representing two direct pathophysiological interventions in estrogen pathway signaling. Both Esr1 and CYP19A1 overexpressing mice responded to letrozole with reduced hyperplastic alveolar nodule prevalence and decreased mammary epithelial cell proliferation. CYP19A1 overexpressing mice were tamoxifen sensitive but Esr1 overexpressing mice were tamoxifen resistant. Increased ER expression occurred with tamoxifen resistance but no consistent changes in progesterone receptor, pSTAT3, pSTAT5, cyclin D1 or cyclin E levels in association with response or resistance were found. RNA-sequencing (RNA-seq) was employed to seek a transcriptome predictive of tamoxifen resistance using these models and a second tamoxifen-resistant model, BRCA1 deficient/Trp53 haploinsufficient mice. Sixty-eight genes associated with immune system processing were upregulated in tamoxifen-resistant Esr1- and Brca1-deficient mice, whereas genes related to aromatic compound metabolic process were upregulated in tamoxifen-sensitive CYP19A1 mice. Interferon regulatory factor 7 was identified as a key transcription factor regulating these 68 immune processing genes. Two loci encoding novel transcripts with high homology to human immunoglobulin lambda-like polypeptide 1 were uniquely upregulated in the tamoxifen-resistant models. Letrozole proved to be a successful alternative to tamoxifen. Further study of transcriptional changes associated with tamoxifen resistance including immune-related genes could expand our mechanistic understanding and lead to biomarkers predictive of escape or response to endocrine therapies

  14. Treatment-associated musculoskeletal and vasomotor symptoms and relapse-free survival in the NCIC CTG MA.27 adjuvant breast cancer aromatase inhibitor trial.

    PubMed

    Stearns, Vered; Chapman, Judith-Anne W; Ma, Cynthia X; Ellis, Matthew J; Ingle, James N; Pritchard, Kathleen I; Budd, G Thomas; Rabaglio, Manuela; Sledge, George W; Le Maitre, Aurélie; Kundapur, Jessica; Liedke, Pedro E R; Shepherd, Lois E; Goss, Paul E

    2015-01-20

    Treatment-emergent symptoms with adjuvant tamoxifen and aromatase inhibitors (AIs) have been associated with superior recurrence-free survival (RFS). We hypothesized that MA.27 anastrozole- or exemestane-treated patients with new or worsening vasomotor and/or joint symptoms would have improved RFS. MA.27 randomly assigned 7,576 postmenopausal women with breast cancer to 5 years of anastrozole or exemestane. Patient-reported symptoms were collected using the Common Terminology Criteria for Adverse Events version 3.0 at protocol-specified baseline and 6- and 12-month clinical visits. Symptoms were considered present with either vasomotor and/or joint complaints. Associations between symptoms and baseline patient characteristics were examined with χ(2) and Fisher's exact tests. Subsequent effects of new or worsening symptoms on RFS were examined with landmark analyses and stratified univariable and multivariable Cox models. We examined the effects of 3-month symptoms arising from unplanned clinic visits as a result of severe toxicity. Patients were assessable if eligible for the MA.27 trial, received some trial therapy, and had no disease recurrence at the end of a symptom assessment period; 96% of patients (n = 7,306 patients) were included at 6 months, and 96% (n = 7,246) were included at 12 months. Thirty-four percent of patients had baseline symptoms. For patients without baseline symptoms, 25% and 52% had new symptoms by 6 and 12 months, respectively. Neither treatment-emergent nor baseline symptoms significantly impacted RFS (P > .10) in patients with or without baseline symptoms. In MA.27, anastrozole or exemestane treatment-emergent symptoms were not associated with improved RFS. Women should be supported through treatment and encouraged to remain on their AI regardless of their symptoms. © 2014 by American Society of Clinical Oncology.

  15. Expression of the IGF and the aromatase/estrogen receptor systems in human adrenal tissues from early infancy to late puberty: implications for the development of adrenarche.

    PubMed

    Belgorosky, Alicia; Baquedano, María Sonia; Guercio, Gabriela; Rivarola, Marco A

    2009-03-01

    Adrenarche is a process of postnatal sexual maturation occurring in higher primates, in which there is an increase in the secretion of adrenal androgens. It is the consequence of a process of postnatal organogenesis characterized by the development of a new zone in the adrenal cortex, the zona reticularis (ZR). The mechanism of this phenomenon remains poorly understood, suggesting that it might be a multifactorial event. A relationship between circulating IGF-I, insulin sensitivity, and adrenal androgens has been postulated. Boys and girls have different patterns of changes in insulin sensitivity at puberty, perhaps secondary to differences in the estrogen milieu. Estrogen effects may also play a role in premature adrenarche. Peripheral or local IGF-1 actions could regulate adrenal progenitor cell proliferation and migration. Since adrenal progenitor cells as well as IGF-I and the IGF-R1 are located in the outer zone of the adrenal cortex during childhood and adolescence, this peripheral cell layer, below the capsule, may contain undifferentiated progenitor cells. Therefore, the IGF-R1 signaling pathway might positively modulate the proliferation and migration of adrenal progenitor cell to stimulate the development of adrenal zones, including ZR. However, no evidence of a direct action of IGF-I on ZR was found. In addition, a role for estrogens in the ontogenesis of ZR is suggested by the presence of aromatase (CYP19) in the subcapsular zona glomerulosa and in the adrenal medulla. Estrogens produced locally could act on ZR by interacting with estrogen receptor beta (ERbeta), but not alpha, and membrane estrogen receptor GPR-30. An estradiol-induced increase in DHEA/cortisol ratio was indeed seen in cultures of adrenocortical cells from post-adrenarche adrenals. In summary, several lines of evidence point to the action of multiple factors, such as local adrenal maturational changes and peripheral metabolic signals, on postnatal human adrenal gland ZR formation.

  16. Endocrine control of sexual behavior in sneaker males of the peacock blenny Salaria pavo: effects of castration, aromatase inhibition, testosterone and estradiol.

    PubMed

    Gonçalves, David; Alpedrinha, João; Teles, Magda; Oliveira, Rui F

    2007-04-01

    The effects of castration and sex steroid manipulations on the expression of sexual behavior were investigated in a small fish, the peacock blenny, Salaria pavo. In this species, large males defend nests and attract females while small "sneaker" males reproduce by imitating the female morphology and courtship behavior in order to approach nests during spawning events and parasitically fertilize eggs. Sneakers switch into nest holders in their second breeding season, thus displaying both male and female-like sexual behavior during their lifetime. We tested the effects of castration and of an aromatase inhibitor (Fadrozole, F), testosterone (T) or 17beta-estradiol (E(2)) implants on the expression of male and female-like behavior in sneakers. Sneakers were either sham-operated, castrated or castrated and implanted with vehicle, F, T+F or E(2)+F. Seven days after the treatment, sneakers were placed in a tank with a nesting male, two ripe females and an available nest. Castrated fish had lower levels of circulating T and increased the time spent displaying female typical nuptial coloration. T implants had the opposite effect, inhibiting the expression of female-like behavior and coloration. E(2) implants had no significant effect on the display of sexual behavior but the frequency of aggressive displays decreased. The results agree with previous findings in sneakers of S. pavo that demonstrated an inhibition of female-like behavior by 11-ketotestosterone (11-KT). The reported increase in T and 11-KT production when sneakers change into nest holders may thus contribute to behaviorally defeminize sneakers. Contrarily, both T and E(2) failed to promote male-like behavior, suggesting that behavioral masculization during tactic switching depends on other neuroendocrine mechanisms or that the time length of the experiment was insufficient to induce male-like behavioral changes in sneakers.

  17. Involvement of pituitary gonadotropins, gonadal steroids and breeding season in sex change of protogynous dusky grouper, Epinephelus marginatus (Teleostei: Serranidae), induced by a non-steroidal aromatase inhibitor.

    PubMed

    Garcia, Carlos Eduardo de O; Araújo, Bruno C; Mello, Paulo H; Narcizo, Amanda de M; Rodrigues-Filho, Jandyr A; Medrado, Andreone T; Zampieri, Ricardo A; Floeter-Winter, Lucile M; Moreira, Renata Guimarães

    2013-10-01

    Two experiments were performed using the aromatase inhibitor (AI) letrozole (100mg/kg) to promote sex change, from female-to-male, in protogynous dusky grouper. One experiment was performed during the breeding season (spring) and the other at the end of the breeding season (summer). During the spring, AI promoted sex change after 9 weeks and the sperm produced was able to fertilize grouper oocytes. During the summer, the sex change was incomplete; intersex individuals were present and sperm was not released by any of the animals. Sex changed gonads had a lamellar architecture; cysts of spermatocytes and spermatozoa in the lumen of the germinal compartment. In the spring, after 4 weeks, 11ketotestosterone (11KT) levels were higher in the AI than in control fish, and after 9 weeks, coincident with semen release, testosterone levels increased in the AI group, while 11KT returned to the initial levels. Estradiol (E2) levels remained unchanged during the experimental period. Instead of decreasing throughout the period, as in control group, 17 α-OH progesterone levels did not change in the AI-treated fish, resulting in higher values after 9 weeks when compared with control fish. fshβ and lhβ gene expression in the AI animals were lower compared with control fish after 9 weeks. The use of AI was effective to obtain functional males during the breeding season. The increase in androgens, modulated by gonadotropins, triggered the sex change, enabling the development of male germ cells, whereas a decrease in E2 levels was not required to change sex in dusky grouper. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Effects of transdermal testosterone gel or an aromatase inhibitor on serum concentration and pulsatility of growth hormone in older men with age-related low testosterone.

    PubMed

    Dias, Jenny Pena; Veldhuis, Johannes D; Carlson, Olga; Shardell, Michelle; Chia, Chee W; Melvin, Denise; Egan, Josephine M; Basaria, Shehzad

    2017-04-01

    Growth hormone is the major regulator of growth and body composition. Pulsatile GH secretion declines exponentially with age. Testosterone replacement is being increasingly offered to older men with age-related low testosterone. Testosterone administration has been shown to stimulate GH secretion. However, little is known about the effect of testosterone aromatization to estradiol on GH pulsatility and its impact on IGF-1 in older men. This randomized controlled proof-of-concept trial investigated the relative effects of testosterone and estradiol on GH pulsatility and IGF-1 in older men with low testosterone. Thirty-seven men, ≥65years with total testosterone <350ng/dL were randomized to 5g transdermal testosterone gel (TT), 1mg oral aromatase inhibitor (AI) or placebo daily for 12months. Primary outcome was deconvolution and approximate entropy analyses of pulsatile including basal and entropic modes of secretion performed at baseline and 3months. Secondary outcomes included IGF-1 evaluated at baseline, 3 and 6months. At 3months, mean GH and in IGF-1 were similar between the three groups. At 6months, IGF-1 significantly increased by Δ 15.3±10.3ng/ml in the TT-group compared to placebo (P=0.03). Both intervention groups significantly increased GH pulse frequency (TT-group, P=0.04; AI-group, P=0.05) compared to placebo. The GH secretory-burst mode (duration) significantly decreased in the TT-group (P=0.0018) compared to placebo while it remained unchanged in the AI-group (P=0.059). In older men, testosterone increases GH pulse frequency while the aromatization to estradiol is involved in the rise of IGF-1 levels. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Tide-related Changes in mRNA Abundance of Aromatases and Estrogen Receptors in the Ovary and Brain of the Threespot Wrasse Halichoeres trimaculatus

    NASA Astrophysics Data System (ADS)

    Oh, Dae-Ju; Hur, Sung-Pyo; Bouchekioua, Selma; Takeuchi, Yuki; Udagawa, Shingo; Aluru, Neelakanteswar; Park, Yong-Ju; Park, Ji-Gweon; Kim, Se-Jae; Moon, Thomas W.; Vijayan, Mathilakath M.; Takemura, Akihiro

    2018-05-01

    The threespot wrasse (Halichoeres trimaculatus; Family Labridae) is a common coral reef species of the Indo-Pacific Ocean. Given that this species spawns daily at high tide (HT), we hypothesized that endocrine changes in relation to gonadal development are synchronized with the tidal cycle. To test this, we examined the transcript abundance of two cytochrome P450 aromatases (cyp19a and cyp19b) and two estrogen receptors (erα and erβ) in the ovary and brain of this species in response to tidal change. When fish were collected around four tidal points [low tide (LT), flood tide (FT), high tide (HT), and ebb tide (ET)], gonadosomatic index and oocyte diameter increased around HT and FT, respectively. Ovulatory follicles were observed in ovaries around HT. Real-time quantitative polymerase-chain reaction revealed that mRNA abundance of cyp19a and erα, but not erβ, in the ovary increased around ET and HT, respectively. On the other hand, mRNA levels of cyp19b in the forebrain were significantly higher around FT. Increases of erα and erβ mRNA abundance around FT were observed in all areas of the brain and the midbrain, respectively. The changes in mRNA abundance of key genes involved in reproduction at specific tidal cycles, along with the development of the vitellogenic oocytes in the ovary, support our hypothesis that synchronization of endocrine changes to the tidal periodicity plays a role in the gonadal development of this species. We hypothesize that conversion of testosterone to E2 in the brain may be associated with the spawning behavior given that the wrasse exhibits group spawning with a territory-holding male around HT.

  20. Expression and localization of aromatase P450AROM, estrogen receptor-α, and estrogen receptor-β in the developing fetal bovine frontal cortex.

    PubMed

    Peruffo, A; Giacomello, M; Montelli, S; Corain, L; Cozzi, B

    2011-06-01

    The enzyme aromatase (P450(AROM)) converts testosterone (T) into 17-β estradiol (E(2)) and is crucial for the control of development of the central nervous system during ontogenesis. The effects of E(2) in various brain areas are mediated by the estrogen receptor alpha (ER-α) and the estrogen receptor beta (ER-β). During fetal development, steroids are responsible for the sexual differentiation of the hypothalamus. Estrogens are also able to exert effects in other brain areas of the fetus including the frontal cortex, where they act through estrogen receptors (ERs) modulating cognitive function and affective behaviors. In this study we have determined the expression profiles of P450(AROM) and ERs in the fetal bovine frontal cortex by quantitative Real-Time PCR (qRT-PCR) throughout the prenatal development. The data show that the patterns of expression of both ERs are strongly correlated during pregnancy and increase in the last stage of gestation. On the contrary, the expression of P450(AROM) has no correlation with ERs expression and is not developmentally regulated. Moreover, we performed immunochemical studies showing that fetal neurons express P450(AROM) and the ERs. P450(AROM) is localized in the cytoplasm and only seldom present in the fine extensions of the cells; ER-α is detected predominantly in the soma whereas ER-β is only present in the nucleus of a few cells. This study provides new data on the development of the frontal cortex in a long gestation mammal with a large convoluted brain. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Pilot study of acupuncture for the treatment of joint symptoms related to adjuvant aromatase inhibitor therapy in postmenopausal breast cancer patients.

    PubMed

    Crew, Katherine D; Capodice, Jillian L; Greenlee, Heather; Apollo, Arlyn; Jacobson, Judith S; Raptis, George; Blozie, Kimberly; Sierra, Alex; Hershman, Dawn L

    2007-12-01

    Aromatase inhibitors (AIs) have become the standard of care for the adjuvant treatment of postmenopausal, hormone-sensitive breast cancer. However, patients receiving AIs may experience joint symptoms, which may lead to early discontinuation of this effective therapy. We hypothesize that acupuncture is a safe and effective treatment for AI-induced arthralgias. Postmenopausal women with early-stage breast cancer who had self-reported musculoskeletal pain related to adjuvant AI therapy were randomized in a crossover study to receive acupuncture twice weekly for 6 weeks followed by observation or vice-versa. The intervention included full body and auricular acupuncture, and a joint-specific point prescription. Outcome measures included the Brief Pain Inventory-Short Form (BPI-SF), Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index, the Functional Assessment of Cancer Therapy-General (FACT-G) quality of life measure, and serum levels of inflammatory markers, IL-1 beta and TNF-alpha. Twenty-one women were enrolled and two discontinued early. From baseline to the end of treatment, patients reported improvement in the mean BPI-SF worst pain scores (5.3 to 3.3, p = 0.01), pain severity (3.7 to 2.5, p = 0.02), and pain-related functional interference (3.1 to 1.7, p = 0.02), as well as the WOMAC function subscale and FACT-G physical well-being (p = 0.02 and 0.04, respectively). No adverse events were reported. In this pilot study, acupuncture reduced AI-related joint symptoms and improved functional ability and was well-tolerated. Musculoskeletal side effects are common among breast cancer survivors on adjuvant AI therapy, therefore, effective treatments are needed for symptom relief and to improve adherence to these life-saving medications.

  2. Down-regulation of heat-shock protein 70 (HSP-70) correlated with responsiveness to neoadjuvant aromatase inhibitor therapy in breast cancer patients.

    PubMed

    Yiu, Christopher C P; Chanplakorn, Niramol; Chan, Monica S M; Loo, Wings T Y; Chow, Louis W C; Toi, Masakazu; Sasano, Hironobu

    2010-09-01

    Aromatase inhibitor (AI) has been established as an effective endocrine therapy in estrogen receptor (ER)-positive postmenopausal breast cancer patients. Our recent proteomic analysis demonstrated that ten proteins were significantly altered in their expression levels before and after the therapy in the patients receiving neoadjuvant AI. Among these newly identified proteins, heat-shock protein 70 (HSP-70) was the most significantly correlated with both clinical and pathological responses. Therefore, in this study, we further evaluated the significance of this HSP-70 alteration using immunohistochemistry. A total of 32 patients treated with neoadjuvant exemestane or letrozole in whom pre- and post-treatment tumor tissues were available were included. Immunohistochemical evaluation of ER, progesterone receptor (PgR), Her-2, Ki-67 and HSP-70 was performed. Results obtained were compared to both clinical and biological responses of the patients. The majority of the patients responded to treatment (16 patients with partial response, 14 with stable disease and 2 with progressive disease). The means of ER, Ki-67 and HSP-70 were significantly different between treatment responders and non-responders. Decrement of HSP-70 and Ki-67 after AI treatment and pretreatment Ki-67 labeling index of >10% tumor cells were significantly associated with clinical responsiveness to AI treatment (p<0.0001). There was a significant positive correlation between changes of HSP-70 and Ki-67 before and after the therapy. Decrement of HSP-70 in breast carcinoma cells plays important roles in therapeutic mechanisms of AIs through suppressing tumor cell proliferation in breast cancer patients.

  3. Effects of 17α-Methyltestosterone and Aromatase Inhibitor Letrozole on Sex Reversal, Gonadal Structure, and Growth in Yellow Catfish Pelteobagrus fulvidraco.

    PubMed

    Shen, Zhi-Gang; Fan, Qi-Xue; Yang, Wei; Zhang, Yun-Long; Wang, Han-Ping

    2015-04-01

    Monosex populations are in demand in many fish species with sexual dimorphism, e.g., better growth performance, higher gonad value, superior ornamental value. From the point of view of research, a monosex population is one of the best materials for investigating sex-determining mechanisms, sex differentiation, and sex-linked markers. Sex reversal of females (phenotypic reversal from XX female to XX male) is the first step in all-female production in species with an XX/XY system for sex determination. In the present study, masculinization of yellow catfish, a species with XX/XY sex determination, was investigated by oral administration of various doses of 17α-methyltestosterone (MT) or an aromatase inhibitor (AI) letrozole (LZ); effects on survival, growth performance, sex ratio, and changes in gonadal structure were evaluated. Three doses (20, 50, and 100 mg kg(-1) diet) of oral MT or LZ were administered to fry from 10 days post-hatching (DPH) to 59 DPH. Oral administration of MT at all doses did not significantly change the ratio of males (45.8%, 33.3%, and 50.0% respectively) compared to the control group (37.5%), while yielding intersex fish at all doses (4.2% to 8.3%). Oral administration of LZ produced a significantly higher proportion of males in all doses (75.5%, 83.3%, and 75.0%, respectively). Additionally, the lowest dose of LZ improved the growth of treated fish compared to the control, and all doses of LZ enhanced spermatogenesis in treated males. © 2015 Marine Biological Laboratory.

  4. GDNF-RET signaling in ER-positive breast cancers is a key determinant of response and resistance to aromatase inhibitors

    PubMed Central

    Morandi, Andrea; Martin, Lesley-Ann; Gao, Qiong; Pancholi, Sunil; Mackay, Alan; Robertson, David; Zvelebil, Marketa; Dowsett, Mitch; Plaza-Menacho, Ivan; Isacke, Clare M.

    2013-01-01

    Most breast cancers at diagnosis are estrogen receptor (ER)-positive and depend on estrogen for growth and survival. Blocking estrogen biosynthesis by aromatase inhibitors (AI) has therefore become a first-line endocrine therapy for post-menopausal women with ER-positive breast cancers. Despite providing substantial improvements in patient outcome, AI resistance remains a major clinical challenge. The receptor tyrosine kinase RET and its co-receptor GFRα1 are upregulated in a subset of ER-positive breast cancers, and the RET ligand, glial-derived neurotrophic factor (GDNF) is upregulated by inflammatory cytokines. Here we report the findings of a multidisciplinary strategy to address the impact of GDNF-RET signaling in the response to AI treatment. In breast cancer cells in 2D and 3D culture, GDNF-mediated RET signaling is enhanced in a model of AI resistance. Further, GDNF-RET signaling promoted the survival of AI-resistant cells and elicited resistance in AI-sensitive cells. Both these effects were selectively reverted by the RET kinase inhibitor NVP-BBT594. Gene expression profiling in ER-positive cancers defined a proliferation-independent GDNF-response signature that prognosed poor patient outcome and, more importantly, predicted poor response to AI treatment with the development of resistance. We validated these findings by demonstrating increased RET protein expression levels in an independent cohort of AI-resistant patient specimens. Together, our results establish GDNF-RET signaling as a rational therapeutic target to combat or delay the onset of AI resistance in breast cancer. PMID:23650283

  5. Cost-effectiveness of dual-energy X-ray absorptiometry plus antiresorptive treatment in Australian women with breast cancer who receive aromatase inhibitors.

    PubMed

    Sowa, P Marcin; Downes, Martin J; Gordon, Louisa G

    2017-03-01

    Postmenopausal women with breast cancer on aromatase inhibitor (AI) treatment are at increased risk of bone mineral density loss, which may lead to minimal trauma fractures. We examined the cost-effectiveness of dual energy X-ray absorptiometry (DXA) with antiresorptive (AR) therapy compared with fracture risk assessment, lifestyle advice, and vitamin supplementation. We used a hypothetical Markov cohort model of lifetime duration for 60-year-old women with early stage breast cancer receiving AIs. The data to inform the model came from medical literature, epidemiological reports, and costing data sets. Two eligibility scenarios for AR therapy were considered: (A) osteoporosis and (B) osteopenia or osteoporosis. The main outcomes were incremental cost per quality-adjusted life years gained and cumulative fractures per 1000 women, calculated relative to the comparator. Key aspects of the model were explored in sensitivity analyses. Due to relatively low effectiveness gains, the outcomes were primarily driven by the costs. The incremental cost per quality-adjusted life year gained was A$47,556 and A$253,000 for scenarios A and B, respectively. The numbers of fractures avoided were 56 and 77 per 1000 women, respectively. The results were most sensitive to the initial probability of osteoporosis, baseline risk of fracture, and cohort starting age. Compared with risk assessment and lifestyle advice only, a DXA scan followed by an AR treatment is potentially cost-effective for women aged 60 and over undergoing AI therapy for early breast cancer. However, the number of fractures averted through this intervention is small.

  6. American Society of Clinical Oncology Clinical Practice Guideline Update on the Use of Pharmacologic Interventions Including Tamoxifen, Raloxifene, and Aromatase Inhibition for Breast Cancer Risk Reduction

    PubMed Central

    Visvanathan, Kala; Chlebowski, Rowan T.; Hurley, Patricia; Col, Nananda F.; Ropka, Mary; Collyar, Deborah; Morrow, Monica; Runowicz, Carolyn; Pritchard, Kathleen I.; Hagerty, Karen; Arun, Banu; Garber, Judy; Vogel, Victor G.; Wade, James L.; Brown, Powel; Cuzick, Jack; Kramer, Barnett S.; Lippman, Scott M.

    2009-01-01

    Purpose To update the 2002 American Society of Clinical Oncology guideline on pharmacologic interventions for breast cancer (BC) risk reduction. Methods A literature search identified relevant randomized trials published since 2002. Primary outcome of interest was BC incidence (invasive and noninvasive). Secondary outcomes included BC mortality, adverse events, and net health benefits. An expert panel reviewed the literature and developed updated consensus guidelines. Results Seventeen articles met inclusion criteria. In premenopausal women, tamoxifen for 5 years reduces the risk of BC for at least 10 years, particularly estrogen receptor (ER) –positive invasive tumors. Women ≤ 50 years of age experience fewer serious side effects. Vascular and vasomotor events do not persist post-treatment across all ages. In postmenopausal women, raloxifene and tamoxifen reduce the risk of ER-positive invasive BC with equal efficacy. Raloxifene is associated with a lower risk of thromboembolic disease, benign uterine conditions, and cataracts than tamoxifen in postmenopausal women. No evidence exists establishing whether a reduction in BC risk from either agent translates into reduced BC mortality. Recommendations In women at increased risk for BC, tamoxifen (20 mg/d for 5 years) may be offered to reduce the risk of invasive ER-positive BC, with benefits for at least 10 years. In postmenopausal women, raloxifene (60 mg/d for 5 years) may also be considered. Use of aromatase inhibitors, fenretinide, or other selective estrogen receptor modulators to lower BC risk is not recommended outside of a clinical trial. Discussion of risks and benefits of preventive agents by health providers is critical to patient decision making. PMID:19470930

  7. Bone health and adherence to vitamin D and calcium therapy in early breast cancer patients on endocrine therapy with aromatase inhibitors.

    PubMed

    Bošković, Lidija; Gašparić, Maja; Petković, Marija; Gugić, Damir; Lovasić, Ingrid Belac; Soldić, Željko; Miše, Branka Petrić; Dabelić, Nina; Vazdar, Ljubica; Vrdoljak, Eduard

    2017-02-01

    Randomized trials involving aromatase inhibitors (AIs) in the adjuvant treatment of breast cancer patients have reported increased osteoporosis risk. Bone loss can be reduced with appropriate life style, vitamin D and calcium supplements, and with bisphosphonate therapy. The aim of this analysis was to investigate adherence to vitamin D and calcium in postmenopausal breast cancer patients receiving adjuvant non-steroidal AIs, and oncologists' adherence to the bone health guidelines. This prospective study included 438 newly diagnosed patients and those who have already been receiving non-steroidal AIs for up to 3.5 years. Median endocrine therapy duration before recruitment in the study was 10.5 months (interquartile 4.8-26.6). Densitometry was performed on 142 patients (32.4%) before initiation of endocrine therapy, and on additional 38 (8.6%) patients at second study visit. Densitometry was not performed on 258 (59%) patients. Vitamin D and calcium were prescribed to 329/438 (75.1%) patients at some point during the study. Patients who took more than 80% of the prescribed dose were considered adherent. Self-reported adherence was 88.4%. Osteoporosis was diagnosed in 24 patients (5.5%) of the total study population, bearing in mind that 258/438 (59%) patients did not have densitometry. Bisphosphonates were prescribed to 54/438 (12.3%) patients, whilst only 19 (35.2%) of those had osteoporosis. In this analysis, lack of oncologists' adherence to the bone health guidelines was observed. In addition, a significant proportion of the patients did not adhere to the vitamin D and calcium. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. In vitro effects of diethylstilbestrol, genistein, 4-tert-butylphenol, and 4-tert-octylphenol on steroidogenic activity of isolated immature rat ovarian follicles

    SciTech Connect

    Myllymaeki, Sari; Haavisto, Tapio; Vainio, Minna

    2005-04-01

    Isolated rat ovarian follicles grow and produce steroid hormones in vitro and so provide a good model for studying the effects of hormonally active compounds on follicular steroidogenesis. We have evaluated the effects of diethylstilbestrol (DES), genistein (GEN) and two alkylphenols, 4-tert-butylphenol (BP) and 4-tert-octylphenol (OP) on the growth, survival, and steroid hormone and cAMP production by isolated 14-day-old rat (Sprague-Dawley) ovarian follicles. During a 5-day culture, FSH was obligatory for follicle growth and increased estradiol and testosterone secretion in a dose-dependent manner. DES (10{sup -6} M) caused the strongest decline in estradiol and testosterone levels but did not havemore » detectable effects on either cAMP production or aromatase enzyme activity. GEN caused a prominent decrease in cAMP and testosterone levels without significant changes in secreted estradiol. The latter, apparently, was due to a dose-dependent stimulation of aromatase enzyme activity in the presence of genistein. Both BP and OP decreased estradiol and testosterone secretion in a dose-dependent manner while no effect on aromatase activity was observed. OP, unlike BP, decreased forskolin-induced cAMP levels. Xenoestrogens at the used concentrations did not interfere with the growth and survival of the follicles. The results indicate that isolated ovarian follicles representing intact morphological and functional units offer a sensitive model system for elucidating the female-specific reproductive effects of environmental chemicals.« less

  9. Dynamic and differential expression of the gonadal aromatase during the process of sexual differentiation in a novel transgenic cyp19a1a-eGFP zebrafish line.

    PubMed

    Hinfray, Nathalie; Sohm, Frédéric; Caulier, Morgane; Chadili, Edith; Piccini, Benjamin; Torchy, Camille; Porcher, Jean-Marc; Guiguen, Yann; Brion, François

    2018-05-15

    In zebrafish, there exists a clear need for new tools to study sex differentiation dynamic and its perturbation by endocrine disrupting chemicals. In this context, we developed and characterized a novel transgenic zebrafish line expressing green fluorescent protein (GFP) under the control of the zebrafish cyp19a1a (gonadal aromatase) promoter. In most gonochoristic fish species including zebrafish, cyp19a1a, the enzyme responsible for the synthesis of estrogens, has been shown to play a critical role in the processes of reproduction and sexual differentiation. This novel cyp19a1a-eGFP transgenic line allowed a deeper characterization of expression and localization of cyp19a1a gene in zebrafish gonads both at the adult stage and during development. At the adult stage, GFP expression was higher in ovaries than in testis. We showed a perfect co-expression of GFP and endogenous Cyp19a1a protein in gonads that was mainly localized in the cytoplasm of peri-follicular cells in the ovary and of Leydig and germ cells in the testis. During development, GFP was expressed in all immature gonads of 20 dpf-old zebrafish. Then, GFP expression increased in early differentiated female at 30 and 35dpf to reach a high GFP intensity in well-differentiated ovaries at 40dpf. On the contrary, males consistently displayed low GFP expression as compared to female whatever their stage of development, resulting in a clear dimorphic expression between both sexes. Interestingly, fish that undergoes ovary-to-testis transition (35 and 40dpf) presented GFP levels similar to males or intermediate between females and males. In this transgenic line our results confirm that cyp19a1a is expressed early during development, before the histological differentiation of the gonads, and that the down-regulation of cyp19a1a expression is likely responsible for the testicular differentiation. Moreover, we show that although cyp19a1a expression exhibits a clear dimorphic expression pattern in gonads during

  10. A novel mutation in the human aromatase gene: insights on the relationship among serum estradiol, longitudinal growth and bone mineral density in an adult man under estrogen replacement treatment.

    PubMed

    Lanfranco, Fabio; Zirilli, Lucia; Baldi, Matteo; Pignatti, Elisa; Corneli, Ginevra; Ghigo, Ezio; Aimaretti, Gianluca; Carani, Cesare; Rochira, Vincenzo

    2008-09-01

    Here we report on a new case of human aromatase deficiency in a man of 26 years of age and present the results of five year follow-up during trandermal estradiol (tE2) substitution, focusing on bone growth and mineralization. The lack of patient's compliance to tE2 treatment, resulting in low but detectable serum estradiol levels, provides helpful information about the physiological estradiol needed in serum to guarantee a complete bone maturation and mineralization. Clinical case report study. Genetic, biochemical and hormonal evaluations and the study of bone health were performed before and during estrogen treatment. Eunuchoid body proportions, unfused epiphyses, tall stature, osteopenia, increase fasting insulin, mild astenozoospermia and a history of right cryptorchidism were present. Baseline serum FSH was slightly above the normal range and estradiol was undetectable. Genetic analysis revealed a pattern of compound heterozygosity due to 23 bp deletion in exon IV and a point mutation in the first nucleotide of intron IX of the CYP19A1 gene, respectively. The closure of epiphyseal cartilage, the normalization of bone BMD and bone turnover markers, and the improvement of insulin levels were reached during tE2 only when serum estradiol raised above 73 pmol/L. Sperm parameters and overweight did not improve with substitutive therapy. This new case of aromatase deficiency underlines the role of estrogen on skeletal maturation, BMD, metabolic abnormalities and gonadal axis. It provides evidence on the need not only of a continuous estrogen replacement, but also of ensuring adequate estradiol levels in serum in order to ensure a complete bone maturation and mineralization and to prevent the worsening of body skeletal proportions. The comprehension of this physiological aspect has relevant clinical significance especially for the development of new therapeutic strategies useful to treat growth disorders by targeting serum estradiol in men.

  11. Ap4A induces apoptosis in human cultured cells.

    PubMed

    Vartanian, A; Alexandrov, I; Prudowski, I; McLennan, A; Kisselev, L

    1999-07-30

    Diadenosine oligophosphates (Ap(n)A) have been proposed as intracellular and extracellular signaling molecules in animal cells. The ratio of diadenosine 5',5'''-P1,P3-triphosphate to diadenosine 5',5'''-P1,P4-tetraphosphate (Ap3A/Ap4A) is sensitive to the cellular status and alters when cultured cells undergo differentiation or are treated with interferons. In cells undergoing apoptosis induced by DNA topoisomerase II inhibitor VP16, the concentration of Ap3A decreases significantly while that of Ap4A increases. Here, we have examined the effects of exogenously added Ap3A and Ap4A on apoptosis and morphological differentiation. Penetration of Ap(n)A into cells was achieved by cold shock. Ap4A at 10 microM induced programmed cell death in human HL60, U937 and Jurkat cells and mouse VMRO cells and this effect appeared to require Ap4A breakdown as hydrolysis-resistant analogues of Ap4A were inactive. On its own, Ap3A induced neither apoptosis nor cell differentiation but did display strong synergism with the protein kinase C activators 12-deoxyphorbol-13-O-phenylacetate and 12-deoxyphorbol-13-O-phenylacetate-20-acetate in inducing differentiation of HL60 cells. We propose that Ap4A and Ap3A are physiological antagonists in determination of the cellular status: Ap4A induces apoptosis whereas Ap3A is a co-inductor of differentiation. In both cases, the mechanism of signal transduction remains unknown.

  12. Endoplasmic reticulum stress mediates withaferin A-induced apoptosis in human renal carcinoma cells.

    PubMed

    Choi, Min Jung; Park, Eun Jung; Min, Kyoung Jin; Park, Jong-Wook; Kwon, Taeg Kyu

    2011-04-01

    The accumulation of misfolded proteins in the lumen of the endoplasmic reticulum (ER) results in cellular stress that initiates a specialized response designated as the unfolded protein response. ER stress has been implicated in a variety of common diseases, such as diabetes, ischemia and neurodegenerative disorders. Withaferin A, a major chemical constituent of Withania somnifera, has been reported to inhibit tumor cell growth. We show that withaferin A induced a dose-dependent apoptotic cell death in several types of human cancer cells, as measured by FACS analysis and PARP cleavage. Treatment of Caki cells with withaferin A induced a number of signature ER stress markers, including phosphorylation of eukaryotic initiation factor-2α (eIF-2 α), ER stress-specific XBP1 splicing, and up-regulation of glucose-regulated protein (GRP)-78. In addition, withaferin A caused up-regulation of CAAT/enhancer-binding protein-homologous protein (CHOP), suggesting the induction of ER stress. Pretreatment with N-acetyl cysteine (NAC) significantly inhibited withaferin A-mediated ER stress proteins and cell death, suggesting that reactive oxygen species (ROS) mediate withaferin A-induced ER stress. Furthermore, CHOP siRNA or inhibition of caspase-4 activity attenuated withaferin A-induced apoptosis. Taken together, the present study provides strong evidence supporting an important role of the ER stress response in mediating withaferin A-induced apoptosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Randomized controlled trial of toremifene 120 mg compared with exemestane 25 mg after prior treatment with a non-steroidal aromatase inhibitor in postmenopausal women with hormone receptor-positive metastatic breast cancer.

    PubMed

    Yamamoto, Yutaka; Ishikawa, Takashi; Hozumi, Yasuo; Ikeda, Masahiko; Iwata, Hiroji; Yamashita, Hiroko; Toyama, Tatsuya; Chishima, Takashi; Saji, Shigehira; Yamamoto-Ibusuki, Mutsuko; Iwase, Hirotaka

    2013-05-16

    After the failure of a non-steroidal aromatase inhibitor (nsAI) for postmenopausal patients with metastatic breast cancer (mBC), it is unclear which of various kinds of endocrine therapy is the most appropriate. A randomized controlled trial was performed to compare the efficacy and safety of daily toremifene 120 mg (TOR120), a selective estrogen receptor modulator, and exemestane 25 mg (EXE), a steroidal aromatase inhibitor. The primary end point was the clinical benefit rate (CBR). The secondary end points were objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and toxicity. Initially, a total of 91 women was registered in the study and randomly assigned to either TOR120 (n = 46) or EXE (n = 45) from October 2008 to November 2011. Three of the 46 patients in the TOR120 arm were not received treatment, 2 patients having withdrawn from the trial by their preference and one having been dropped due to administration of another SERM. When analyzed after a median observation period of 16.9 months, the intention-to-treat analysis showed that there were no statistical difference between TOR120 (N = 46) and EXE (n = 45) in terms of CBR (41.3% vs. 26.7%; P = 0.14), ORR (10.8% vs. 2.2%; P = 0.083), and OS (Hazard ratio, 0.60; P = 0.22). The PFS of TOR120 was longer than that of EXE, the difference being statistically significant (Hazard ratio, 0.61, P = 0.045). The results in treatment-received cohort (N = 88) were similar to those in ITT cohort. Both treatments were well-tolerated with no severe adverse events, although the treatment of 3 of 43 women administered TOR120 was stopped after a few days because of nausea, general fatigue, hot flush and night sweating. TOR120, as a subsequent endocrine therapy for mBC patients who failed non-steroidal AI treatment, could potentially be more beneficial than EXE. UMIN000001841.

  14. Randomized controlled trial of toremifene 120 mg compared with exemestane 25 mg after prior treatment with a non-steroidal aromatase inhibitor in postmenopausal women with hormone receptor-positive metastatic breast cancer

    PubMed Central

    2013-01-01

    Background After the failure of a non-steroidal aromatase inhibitor (nsAI) for postmenopausal patients with metastatic breast cancer (mBC), it is unclear which of various kinds of endocrine therapy is the most appropriate. A randomized controlled trial was performed to compare the efficacy and safety of daily toremifene 120 mg (TOR120), a selective estrogen receptor modulator, and exemestane 25 mg (EXE), a steroidal aromatase inhibitor. The primary end point was the clinical benefit rate (CBR). The secondary end points were objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and toxicity. Methods Initially, a total of 91 women was registered in the study and randomly assigned to either TOR120 (n = 46) or EXE (n = 45) from October 2008 to November 2011. Three of the 46 patients in the TOR120 arm were not received treatment, 2 patients having withdrawn from the trial by their preference and one having been dropped due to administration of another SERM. Results When analyzed after a median observation period of 16.9 months, the intention-to-treat analysis showed that there were no statistical difference between TOR120 (N = 46) and EXE (n = 45) in terms of CBR (41.3% vs. 26.7%; P = 0.14), ORR (10.8% vs. 2.2%; P = 0.083), and OS (Hazard ratio, 0.60; P = 0.22). The PFS of TOR120 was longer than that of EXE, the difference being statistically significant (Hazard ratio, 0.61, P = 0.045). The results in treatment-received cohort (N = 88) were similar to those in ITT cohort. Both treatments were well-tolerated with no severe adverse events, although the treatment of 3 of 43 women administered TOR120 was stopped after a few days because of nausea, general fatigue, hot flush and night sweating. Conclusions TOR120, as a subsequent endocrine therapy for mBC patients who failed non-steroidal AI treatment, could potentially be more beneficial than EXE. Trial registration number UMIN000001841 PMID:23679192

  15. Use of MR-based trabecular bone microstructure analysis at the distal radius for osteoporosis diagnostics: a study in post-menopausal women with breast cancer and treated with aromatase inhibitor.

    PubMed

    Baum, Thomas; Karampinos, Dimitrios C; Seifert-Klauss, Vanadin; Pencheva, Tsvetelina D; Jungmann, Pia M; Rummeny, Ernst J; Müller, Dirk; Bauer, Jan S

    2016-01-01

    Treatment with aromatase inhibitor (AI) is recommended for post-menopausal women with hormone-receptor positive breast cancer. However, AI therapy is known to induce bone loss leading to osteoporosis with an increased risk for fragility fractures. The purpose of this study was to investigate whether changes of magnetic resonance (MR)-based trabecular bone microstructure parameters as advanced imaging biomarker can already be detected in subjects with AI intake but still without evidence for osteoporosis according to dual energy X-ray absorptiometry (DXA)-based bone mineral density (BMD) measurements as current clinical gold standard. Twenty-one postmenopausal women (62±6 years of age) with hormone-receptor positive breast cancer, ongoing treatment with aromatase inhibitor for 23±15 months, and no evidence for osteoporosis (current DXA T-score greater than -2.5) were recruited for this study. Eight young, healthy women (24±2 years of age) were included as controls. All subjects underwent 3 Tesla magnetic resonance imaging (MRI) of the distal radius to assess the trabecular bone microstructure. Trabecular bone microstructure parameters were not significantly (p>0.05) different between subjects with AI intake and controls, including apparent bone fraction (0.42±0.03 vs. 0.42±0.05), trabecular number (1.95±0.10 mm(-1) vs 1.89±0.15 mm(-1)), trabecular separation (0.30±0.03 mm vs 0.31±0.06 mm), trabecular thickness (0.21±0.01 mm vs 0.22±0.02 mm), and fractal dimension (1.70±0.02 vs. 1.70±0.03). These findings suggest that the initial deterioration of trabecular bone microstructure as measured by MRI and BMD loss as measured by DXA occur not sequentially but rather simultaneously. Thus, the use of MR-based trabecular bone microstructure assessment is limited as early diagnostic biomarker in this clinical setting.

  16. Cost utility and budget impact of third-generation aromatase inhibitors for advanced breast cancer: a literature-based model analysis of costs in the Italian National Health Service.

    PubMed

    Marchetti, Monia; Caruggi, Mauro; Colombo, Giorgio

    2004-09-01

    Third-generation aromatase inhibitors are effective alternatives to tamoxifen in patients with advanced breast cancer. However, their acquisition costs might burden fixed-budget health care systems. This study is a decision analysis of the clinical and economic consequences of alternative first-line hormone therapies for postmenopausal women with estrogen receptor-positive metastatic breast cancer in a real-life Italian health care setting. A Markov model was developed to describe disease evolution according to data from previously published, randomized clinical trials. The costs incurred by a local community hospital in the Italian National Health Service were considered (year-2003 values). Clinical data were taken from previously published trials. A 3% discount rate was applied to both resources and life-years gained. Based on model estimates, mean survival times with the third-generation aromatase inhibitors anastrozole and letrozole were 30.72 and 30.64 months, respectively, as opposed to 27.28 months with tamoxifen. Mean survival times after adjustment for quality of life were 18.84 and 18.78 months with anastrozole and letrozole, respectively, and 16.14 months with tamoxifen. Baseline analysis produced incremental cost-effectiveness ratios per quality-adjusted life-year gained of 10,795 Euro (95% CI, 7737 Euro-12,899 Euro) and 16,886 Euro (95% CI, 9117 Euro-15,465 Euro) for anastrozole and letrozole, respectively, compared with tamoxifen. The observed difference between the 2 cost-utility ratios may have been mainly due to the higher acquisition costs of letrozole compared with anastrozole. Despite similar incremental cost-effectiveness ratios, anastrozole and letrozole might increase the budget for advanced breast cancer care by 12% and 18%, respectively, based on the year-2003 Italian market prices of the 2 drugs. In this cost-effectiveness analysis using previously published clinical data and year-2003 cost data from a community hospital in the Italian

  17. Non-ovarian aromatization is required to activate female sexual motivation in testosterone-treated ovariectomized quail

    PubMed Central

    de Bournonville, Catherine; Balthazart, Jacques; Ball, Gregory F.; Cornil, Charlotte A.

    2016-01-01

    Although aromatase is expressed in both male and female brains, its functional significance in females remains poorly understood. In female quail, sexual receptivity is activated by estrogens. However it is not known whether sexual motivation is similarly estrogen-dependent and whether estrogens locally produced in the brain contribute to these behavioral responses. Four main experiments were designed to address these questions. In experiment 1 chronic treatment of females with the anti-estrogen tamoxifen decreased their receptivity, confirming that this response is under the control of estrogens. In experiment 2 chronic treatment with tamoxifen significantly decreased sexual motivation as treated females no longer approached a sexual partner. In experiment 3 (a) ovariectomy (OVX) induced a significant decrease of time spent near the male and a significantly decreased receptivity compared to gonadally intact females, (b) treatment with testosterone (OVX+T) partially restored these responses and (c) this effect of T was prevented when estradiol synthesis was inhibited by the potent aromatase inhibitor Vorozole (OVX+T+VOR). Serum estradiol concentration was significantly higher in OVX+T than in OVX or OVX+T+VOR females. Together these data demonstrate that treatment of OVX females with T increases sexual motivation and that these effects are mediated at least in part by non-gonadal aromatization of the androgen. Finally, assays of aromatase activity on brain and peripheral tissues (Experiment 4) strongly suggest that brain aromatization contributes to behavioral effects observed here following T treatment but alternative sources of estrogens (e.g. liver) should also be considered. PMID:27189762

  18. A comparison of the effect of short-term aromatase inhibitor (letrozole) and GnRH agonist (triptorelin) versus case control on pregnancy rate and symptom and sign recurrence after laparoscopic treatment of endometriosis.

    PubMed

    Alborzi, Saeed; Hamedi, Bahareh; Omidvar, Azizeh; Dehbashi, Sedigheh; Alborzi, Soroosh; Alborzi, Mehrnoosh

    2011-07-01

    To compare the role of an aromatase inhibitor (letrozole) with a GnRH agonist (triptorelin) versus case control on the pregnancy rate and recurrence of symptoms and signs in patients with endometriosis. In a prospective randomized clinical trial, after treatment of 144 infertile women in their reproductive age by laparoscopy (whose endometriosis was confirmed by prior laparoscopy), they were divided into 3 groups: group 1 (47 cases) who received letrozole for 2 months, group 2 (40 patients) who were prescribed triptorelin for 2 months and group 3 who were 57 patients in the control group and did not receive any medication. We followed up each group at least for 12 months after their restoration of regular cycle. Pregnancy rate was 23.4% in group 1, 27.5% in group 2, and 28.1% in group 3. The results did not show significant differences among the 3 groups. Recurrence rate of endometriosis was 6.4% in group 1, 5% group 2 and 5.3% in group 3, which was not statistically significantly different as well. Pregnancy rate and endometriosis recurrence rate are comparable among the 3 groups.

  19. Brain aromatase (cyp19a1b) and gonadotropin releasing hormone (gnrh2 and gnrh3) expression during reproductive development and sex change in black sea bass (Centropristis striata).

    PubMed

    Breton, Timothy S; DiMaggio, Matthew A; Sower, Stacia A; Berlinsky, David L

    2015-03-01

    Teleost fish exhibit diverse reproductive strategies, and some species are capable of changing sex. The influence of many endocrine factors, such as gonadal steroids and neuropeptides, has been studied in relation to sex change, but comparatively less research has focused on gene expression changes within the brain in temperate grouper species with non-haremic social structures. The purpose of the present study was to investigate gonadotropin releasing hormone (GnRH) and brain aromatase (cyp19a1b) gene expression patterns during reproductive development and sex change in protogynous (female to male) black sea bass (Centropristis striata). Partial cDNA fragments for cyp19a1b and eef1a (a reference gene) were identified, and included with known gnrh2 and gnrh3 sequences in real time quantitative PCR. Elevated cyp19a1b expression was evident in the olfactory bulbs, telencephalon, optic tectum, and hypothalamus/midbrain region during vitellogenic growth, which may indicate changes in the brain related to neurogenesis or sexual behavior. In contrast, gnrh2 and gnrh3 expression levels were largely similar among gonadal states, and all three genes exhibited stable expression during sex change. Although sex change in black sea bass is not associated with dramatic changes in GnRH or cyp19a1b gene expression among brain regions, these genes may mediate processes at other levels, such as within individual hypothalamic nuclei, or through changes in neuron size, that warrant further research. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. The comparision of effect of microdose GnRH-a flare-up, GnRH antagonist/aromatase inhibitor letrozole and GnRH antagonist/clomiphene citrate protocols on IVF outcomes in poor responder patients.

    PubMed

    Ozcan Cenksoy, Pinar; Ficicioglu, Cem; Kizilkale, Ozge; Suhha Bostanci, Mehmet; Bakacak, Murat; Yesiladali, Mert; Kaspar, Cigdem

    2014-07-01

    To compare the effects of microdose GnRH-a flare-up, GnRH antagonist/aromatase inhibitor letrozole and GnRH antagonist/clomiphene citrate protocols on IVF outcomes in poor responder patients. Of 225 patients, 83 patients were in microdose flare-up group (Group 1), 70 patients were in GnRH antagonist/letrozole group (Group 2) and 72 patients were in GnRH antagonist/clomiphene citrate group (Group 3). Demographic and endocrine characteristics, the total number of oocytes retrieved, cancellation rate and clinical pregnancy rate were collected Results: Total dosage of gonadotropins (p=0.002) and serum E2 levels on the day of hCG administration (p=0.010) were significantly higher and duration of stimulations (p=0.03) was significantly longer in group 1. The number of oocytes retrieved was significantly greater in group 1 and 2 when compare to those of group 3 (p=0,000). There was a trend towards increasing cycle cancellation rates with GnRH antagonist/clomiphene citrate and GnRH antagonist/letrozole. Our finding suggest that the results of microdose flare-up protocol are better than other two used treatment protocols, in terms of maximum estradiol levels, number of mature oocytes retrieved, and cancellation rate and it still seems to be superior the ovarian stimulation regime for the poor responder patients.

  1. Activities.

    ERIC Educational Resources Information Center

    Mathematics Teacher, 1982

    1982-01-01

    The material presented is designed to help students explore geometric patterns involving Fibonnaci numbers and the golden ratio, and to aid in review of basic geometry skills. Worksheet masters intended for duplication are provided. Suggestions are made of possible classroom extensions to the initial activities. (MP)

  2. Evaluation of potential endocrine activity of 2,4-dichlorophenoxyacetic acid using in vitro assays.

    PubMed

    Coady, Katherine K; Kan, H Lynn; Schisler, Melissa R; Gollapudi, B Bhaskar; Neal, Barbara; Williams, Amy; LeBaron, Matthew J

    2014-08-01

    The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was evaluated in five in vitro screening assays to assess the potential for interaction with the androgen, estrogen and steroidogenesis pathways in the endocrine system. The assays were conducted to meet the requirements of the in vitro component of Tier 1 of the United States Environmental Protection Agency's Endocrine Disruptor Screening Program (EDSP), and included assays for estrogen receptor (ER) binding (rat uterine cytosol ER binding assay), ER-mediated transcriptional activation (HeLa-9903-ERα transactivation assay), androgen receptor (AR) binding (rat prostate cytosol AR binding assay), aromatase enzymatic activity inhibition (recombinant human CYP19 aromatase inhibition assay), and interference with steroidogenesis (H295R steroidogenesis assay). Results from these five assays demonstrated that 2,4-D does not have the potential to interact in vitro with the estrogen, androgen, or steroidogenesis pathways. These in vitro data are consistent with a corresponding lack of endocrine effects observed in apical in vivo animal studies, and thus provide important supporting data valuable in a comprehensive weight of evidence evaluation indicating a low potential of 2,4-D to interact with the endocrine system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Complexation of cytochrome P-450 isozymes in hepatic microsomes from SKF 525-A-induced rats.

    PubMed

    Murray, M

    1988-05-01

    Potassium ferricyanide-elicited reactivation of steroid hydroxylase activities, in hepatic microsomes from SKF 525-A-induced male rats, was used as an indicator of complex formation between individual cytochrome P-450 isozymes and the SKF 525-A metabolite. Induction of male rats with SKF 525-A (50 mg/kg for three days) led to apparent increases in androst-4-ene-3,17-dione 16 beta- and 6 beta-hydroxylation to 6.7- and 3-fold of control activities. Steroid 7 alpha-hydroxylase activity was decreased to 0.8-fold of control and 16 alpha-hydroxylation was unchanged. Ferricyanide-elicited dissociation of the SKF 525-A metabolite-P-450 complex revealed an even greater induction of 16 beta- and 6 beta-hydroxylase activities (to 1.8- and 1.6-fold of activities in the absence of ferricyanide). Androst-4-ene-3,17-dione 16 alpha-hydroxylase activity increased 2-fold after ferricyanide but 7 alpha-hydroxylase activity was unaltered. An antibody directed against the male-specific cytochrome P-450 UT-A decreased androst-4-ene-3,17-dione 16 alpha-hydroxylase activity to 13% of control in hepatic microsomes from untreated rats. In contrast, 16 alpha-hydroxylase activity in microsomes from SKF 525-A-induced rats, before and after dissociation with ferricyanide, was reduced by anti UT-A IgG to 32 and 19% of the respective uninhibited controls. Considered together, these observations strongly suggest that the phenobarbital-inducible cytochrome P-450 isozymes PB-B and PCN-E are present in an inactive complexed state in microsomes from SKF 525-A-induced rat liver. Further, the increased susceptibility of androst-4-ene-3,17-dione 16 alpha-hydroxylase activity to inhibition by an antibody to cytochrome P-450 UT-A, following ferricyanide treatment of microsomes, suggests that this male sexually differentiated enzyme is also complexed after in vivo SKF 525-A dosage. In contrast, the constitutive isozyme cytochrome P-450 UT-F, which is active in steroid 7 alpha-hydroxylation, does not appear

  4. The protective effect of vildagliptin in chronic experimental cyclosporine A-induced hepatotoxicity.

    PubMed

    El-Sherbeeny, Nagla A; Nader, Manar A

    2016-03-01

    The study examined the effect of dipeptidyl peptidase-4 (DPP-4) inhibitor, vildagliptin, in cyclosporine (CsA)-induced hepatotoxicity. Rats were divided into 4 groups treated for 28 days: control (vehicle), vildagliptin (10 mg/kg, orally), CsA (20 mg/kg, s.c.), and CsA-vildagliptin group. Liver function was assessed by measuring serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (γGT), lactate dehydrogenase (LDH), and albumin, and histopathological changes of liver were examined. Oxidative stress markers were evaluated. Assessment of nuclear factor-kappa B (NF-κB) activity in hepatic nuclear extract, serum DPP-4, and expression of Bax and Bcl2 were also done. CsA-induced hepatotoxicity was evidenced by increase in serum levels of AST, ALT, and γGT; a decrease in serum albumin; and a significant alteration in hepatic architecture. Also, significant increase in thiobarbituric acid reactive substance (TBARS) and decrease in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione (GSH) levels, increased expression Bax proteins with deceased expression of Bcl2, and increased hepatic activity of NF-κB and serum DPP-4 level were observed upon CsA treatment. Vildagliptin significantly improved all altered parameters induced by CsA administration. Vildagliptin has the potential to protect the liver against CsA-induced hepatotoxicity by reducing oxidative stress, DPP-4 activity, apoptosis, and inflammation.

  5. Separation of concanavalin A-induced human suppressor and helper T cells by the autologous erythrocyte rosette technique.

    PubMed

    Sakane, T; Honda, M; Taniguchi, Y; Kotani, H

    1981-08-01

    Very few normal human peripheral blood T cells are capable of binding autologous erythrocytes to form rosettes, whereas in the T cell population activated by concanavalin A (Con A) the autorosette levels are markedly enhanced. Fractionation of the Con A-activated T cells with autologous erythrocytes into autorosetting and nonrosetting cells demonstrates that suppressor, but not helper, activity resides in the autorosetting population, whereas the reverse is true of the nonrosetting population. Both these activities are found to be Con A dependent. The Con A-induced human suppressor cells can be identified and separated from the Con A-induced human helper cells by the autorosette technique. Studies on the surface properties of autorosetting and nonrosetting T cells indicate that there is little correlation between the activated suppressor and helper T cell subsets defined by autorosette technique and either those defined by monoclonal antibodies (which are able to distinguish these subsets in the resting but not activated T cells) or those defined by Fc receptors. Since the autorosetting T cell population (which acts as suppressor cells) bears receptors for peanut agglutinin, the nature of Con A-induced human suppressor cells appears to be analogous to that of Con A-induced murine suppressor cells.

  6. Salidroside mediates apoptosis and autophagy inhibition in concanavalin A-induced liver injury

    PubMed Central

    Feng, Jiao; Niu, Peiqin; Chen, Kan; Wu, Liwei; Liu, Tong; Xu, Shizan; Li, Jingjing; Li, Sainan; Wang, Wenwen; Lu, Xiya; Yu, Qiang; Liu, Ning; Xu, Ling; Wang, Fan; Dai, Weiqi; Xia, Yujing; Fan, Xiaoming; Guo, Chuanyong

    2018-01-01

    Salidroside (Sal) is a glycoside extract from Rhodiola rosea L. with anti-inflammatory, antioxidant, anticancer and cardioprotective properties. The present study explored the protective effects and the possible mechanisms of Sal on concanavalin A (ConA)-induced liver injury in mice. Balb/C mice were divided into five groups: Normal control (injected with normal saline), ConA (25 mg/kg), Sal (10 mg/kg) +ConA, Sal (20 mg/kg) + ConA (Sal injected 2 h prior to ConA injection) and Sal (20 mg/kg) only. The serum levels of liver enzymes, pro-inflammatory cytokines, and apoptosis- and autophagy-associated marker proteins were determined at 2, 8 and 24 h after ConA injection. LY294002 was further used to verify whether the phosphoinositide 3-kinase (PI3K)/Akt pathway was activated. Primary hepatocytes were isolated to verify the effect of Sal in vitro. The results indicated that Sal was a safe agent to reduce pathological damage and serum liver enzymes in ConA-induced liver injury. Sal suppressed inflammatory reactions in serum and liver tissues, and activated the PI3K/Akt signaling pathway to inhibit apoptosis and autophagy in vivo and in vitro, which could be reversed by LY294002. In conclusion, Sal attenuated ConA-induced liver injury by modulating PI3K/Akt pathway-mediated apoptosis and autophagy in mice.

  7. Epigenetic activation of the prostaglandin receptor EP4 promotes resistance to endocrine therapy for breast cancer

    PubMed Central

    Hiken, Jeffrey F.; McDonald, James I.; Decker, Keith F.; Sanchez, Cesar; Hoog, Jeremy; VanderKraats, Nathan D.; Jung, Kyle L.; Akinhanmi, Margaret; Rois, Lisa E.; Ellis, Matthew J.; Edwards, John R.

    2016-01-01

    Approximately 75% of breast cancers express estrogen receptor α (ERα) and depend on estrogen signals for continued growth. Aromatase inhibitors (AIs) prevent estrogen production and inhibit estrogen receptor signaling, resulting in decreased cancer recurrence and mortality. Advanced tumors treated with AIs almost always develop resistance to these drugs via the up-regulation of alternative growth signals. The mechanisms that drive this resistance—especially epigenetic events that alter gene expression—are however not well understood. Genome-wide DNA methylation and expression analysis of cell line models of acquired aromatase inhibitor resistance indicated that prostaglandin E2 receptor 4 (PTGER4) is up-regulated after demethylation in resistant cells. Knockdown and inhibitor studies demonstrate that PTGER4 is essential for estrogen independent growth. Our exploratory analysis of downstream signaling indicates that PTGER4 likely promotes AI resistance via ligand independent activation of the ERα-cofactor CARM1. We believe that we have discovered a novel epigenetic mechanism for altering cell signaling and acquiring endocrine therapy resistance. Our findings indicate that PTGER4 is a potential drug target in AI resistant cancers. Additionally, the epigenetic component of PTGER4 regulation suggests that further study of PTGER4 may yield valuable insights into how DNA methylation-targeted diagnoses and treatments can improve AI resistant breast cancer treatment. PMID:27869171

  8. Ultra-low-dose estriol and Lactobacillus acidophilus vaginal tablets (Gynoflor(®)) for vaginal atrophy in postmenopausal breast cancer patients on aromatase inhibitors: pharmacokinetic, safety, and efficacy phase I clinical study.

    PubMed

    Donders, Gilbert; Neven, Patrick; Moegele, Maximilian; Lintermans, Anneleen; Bellen, Gert; Prasauskas, Valdas; Grob, Philipp; Ortmann, Olaf; Buchholz, Stefan

    2014-06-01

    Phase I pharmacokinetic (PK) study assessed circulating estrogens in breast cancer (BC) patients on a non-steroidal aromatase inhibitor (NSAI) with vaginal atrophy using vaginal ultra-low-dose 0.03 mg estriol (E3) and Lactobacillus combination vaginal tablets (Gynoflor(®)). 16 women on NSAI with severe vaginal atrophy applied a daily vaginal tablet of Gynoflor(®) for 28 days followed by a maintenance therapy of 3 tablets weekly for 8 weeks. Primary outcomes were serum concentrations and PK of E3, estradiol (E2), and estrone (E1) using highly sensitive gas chromatography-mass spectrometry. Secondary outcomes were clinical measures for efficacy and side effects; microscopic changes in vaginal epithelium and microflora; and changes in serum FSH, LH, and sex hormone-binding globulin. Compared with baseline, serum E1 and E2 did not increase in any of the women at any time following vaginal application. Serum E3 transiently increased after the first application in 15 of 16 women, with a maximum of 168 pg/ml 2-3 h post-insertion. After 4 weeks, serum E3 was slightly increased in 8 women with a maximum of 44 pg/ml. The vaginal atrophy resolved or improved in all women. The product was well tolerated, and discontinuation of therapy was not observed. The low-dose 0.03 mg E3 and Lactobacillus acidophilus vaginal tablets application in postmenopausal BC patients during AI treatment suffering from vaginal atrophy lead to small and transient increases in serum E3, but not E1 or E2, and therefore can be considered as safe and efficacious for treatment of atrophic vaginitis in BC patients taking NSAIs.

  9. Endocrine therapy for postmenopausal women with hormone receptor-positive her2-negative advanced breast cancer after progression or recurrence on nonsteroidal aromatase inhibitor therapy: a Canadian consensus statement.

    PubMed

    Pritchard, K I; Gelmon, K A; Rayson, D; Provencher, L; Webster, M; McLeod, D; Verma, S

    2013-02-01

    Approximately 22,700 Canadian women were expected to be diagnosed with breast cancer in 2012. Despite improvements in screening and adjuvant treatment options, a substantial number of postmenopausal women with hormone receptor positive (hr+) breast cancer will continue to develop metastatic disease during or after adjuvant endocrine therapy. Guidance on the selection of endocrine therapy for patients with hr+ disease that is negative for the human epidermal growth factor receptor 2 (her2-) and that has relapsed or progressed on earlier nonsteroidal aromatase inhibitor (nsai) therapy is of increasing clinical importance. Exemestane, fulvestrant, and tamoxifen are approved therapeutic options in this context. Four phase iii trials involving 2876 patients-efect, sofea, confirm, and bolero-2-have assessed the efficacy of various treatment options in this clinical setting. Data from those trials suggest that standard-dose fulvestrant (250 mg monthly) and exemestane are of comparable efficacy, that doubling the dose of fulvestrant from 250 mg to 500 mg monthly results in a 15% reduction in the risk of progression, and that adding everolimus to exemestane (compared with exemestane alone) results in a 57% reduction in the risk of progression, albeit with increased toxicity. Multiple treatment options are now available to women with hr+ her2- advanced breast cancer recurring or progressing on earlier nsai therapy, although current clinical trial data suggest more robust clinical efficacy with everolimus plus exemestane. Consideration should be given to the patient's age, functional status, and comorbidities during selection of an endocrine therapy, and use of a proactive everolimus safety management strategy is encouraged.

  10. Endocrine therapy for postmenopausal women with hormone receptor–positive her2–negative advanced breast cancer after progression or recurrence on nonsteroidal aromatase inhibitor therapy: a Canadian consensus statement

    PubMed Central

    Pritchard, K.I.; Gelmon, K.A.; Rayson, D.; Provencher, L.; Webster, M.; McLeod, D.; Verma, S.

    2013-01-01

    Approximately 22,700 Canadian women were expected to be diagnosed with breast cancer in 2012. Despite improvements in screening and adjuvant treatment options, a substantial number of postmenopausal women with hormone receptor positive (hr+) breast cancer will continue to develop metastatic disease during or after adjuvant endocrine therapy. Guidance on the selection of endocrine therapy for patients with hr+ disease that is negative for the human epidermal growth factor receptor 2 (her2–) and that has relapsed or progressed on earlier nonsteroidal aromatase inhibitor (nsai) therapy is of increasing clinical importance. Exemestane, fulvestrant, and tamoxifen are approved therapeutic options in this context. Four phase iii trials involving 2876 patients—efect, sofea, confirm, and bolero-2—have assessed the efficacy of various treatment options in this clinical setting. Data from those trials suggest that standard-dose fulvestrant (250 mg monthly) and exemestane are of comparable efficacy, that doubling the dose of fulvestrant from 250 mg to 500 mg monthly results in a 15% reduction in the risk of progression, and that adding everolimus to exemestane (compared with exemestane alone) results in a 57% reduction in the risk of progression, albeit with increased toxicity. Multiple treatment options are now available to women with hr+ her2– advanced breast cancer recurring or progressing on earlier nsai therapy, although current clinical trial data suggest more robust clinical efficacy with everolimus plus exemestane. Consideration should be given to the patient’s age, functional status, and comorbidities during selection of an endocrine therapy, and use of a proactive everolimus safety management strategy is encouraged. PMID:23443928

  11. Different patterns in the risk of newly developed fatty liver and lipid changes with tamoxifen versus aromatase inhibitors in postmenopausal women with early breast cancer: A propensity score-matched cohort study.

    PubMed

    Hong, Namki; Yoon, Han Gyul; Seo, Da Hea; Park, Seho; Kim, Seung Il; Sohn, Joo Hyuk; Rhee, Yumie

    2017-09-01

    Management of metabolic complications of long-term adjuvant endocrine therapy in early breast cancer remained an unmet need. We aimed to compare the effects of tamoxifen (TMX) and aromatase inhibitors (AIs) on the risk of fatty liver in conjunction with longitudinal changes in the serum lipid parameters. Among 1203 subjects who were taking adjuvant TMX or AI (anastrozole or letrozole) without fatty liver at baseline, those taking TMX or AI were 1:1 matched on the propensity score. The primary outcome was newly developed fatty liver detected on annual liver ultrasonography. Among 328 matched subjects (mean age 53.5 years, body mass index 22.9 kg/m 2 ), 62 cases of fatty liver in the TMX group and 41 cases in the AI group were detected in a total of 987.4 person-years. The incidence rate of fatty liver was higher in the TMX group than in the AI group (128.7 versus 81.1 per 1000 person-years, P = 0.021), particularly within the first 2 years of therapy. TMX was associated with an increased 5-year risk of newly developed fatty liver (adjusted hazard ratio 1.61, P = 0.030) compared with AI independent of obesity and cholesterol level. Subjects who developed fatty liver had higher triglycerides (TGs) and lower high-density lipoprotein cholesterol (HDL-C) level at baseline than those without, which was sustained during follow-up despite the serum cholesterol-lowering effect of TMX. TMX independently increased the 5-year risk of newly developed fatty liver compared with AI in postmenopausal women with early breast cancer. Our findings suggest the need for considering the risk of fatty liver as a different adverse event profile between AI and TMX, particularly in patients with obesity, high TGs and low HDL-C. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Inhibition of drug metabolizing cytochrome P450s by the aromatase inhibitor drug letrozole and its major oxidative metabolite 4,4′-methanol-bisbenzonitrile in vitro

    PubMed Central

    Jeong, Seongwook; Woo, Margaret M.; Flockhart, David A.

    2009-01-01

    Purpose To determine the inhibitory potency of letrozole and its main human metabolite, 4,4′-methanol-bisbenzonitrilee, on the activities of eight cytochrome P450 (CYP) enzymes. Methods Letrozole and its metabolite were incubated with human liver microsomes (HLMs) (or expressed CYP isoforms) and NADPH in the absence (control) and presence of the test inhibitor. Results Letrozole was a potent competitive inhibitor of CYP2A6 (Ki 4.6 ± 0.05 μM and 5.0 ± 2.4 μM in HLMs and CYP2A6, respectively) and a weak inhibitor of CYP2C19 (Ki 42.2 μM in HLMs and 33.3 μM in CYP2C19), while its metabolite showed moderate inhibition of CYP2C19 and CYP2B6. Letrozole or its metabolite had negligible effect on other CYPs. Conclusions Based on the in vitro Ki values, letrozole is predicted to be a weak inhibitor of CYP2A6 in vivo. Letrozole and its major human metabolite show inhibitory activity towards other CYPs, but clinically relevant drug interactions seem less likely as the Ki values are above the therapeutic plasma concentrations of letrozole. PMID:19198839

  13. Effect of ultra-low-dose estriol and lactobacilli vaginal tablets (Gynoflor®) on inflammatory and infectious markers of the vaginal ecosystem in postmenopausal women with breast cancer on aromatase inhibitors.

    PubMed

    Donders, G; Bellen, G; Neven, P; Grob, P; Prasauskas, V; Buchholz, S; Ortmann, O

    2015-10-01

    This study was a detailed microscopic analysis of the changes of vaginal microflora characteristics after application of 0.03 mg estriol-lactobacilli combination on the vaginal ecosystem in postmenopausal breast cancer (BC) survivors on aromatase inhibitors (AI) with severe atrophic vaginitis. A total of 16 BC women on AI applied daily one vaginal tablet of Gynoflor® for 28 days followed by a maintenance therapy of three tablets weekly for 8 weeks. During four follow up visits a smear from the upper lateral vaginal wall was analysed by phase contrast microscopy at 400 times magnification in order to classify the lactobacillary grades(LBG), bacterial vaginosis (BV), aerobic vaginitis (AV), vulvovaginal candidosis (VVC), proportional number of leukocytes and evidence of parabasal cells and epitheliolysis. LBG improved from 81% LBG-III at entry to 88% LBG-I&IIa after 2 weeks of initial therapy, which further improved upon follow up (p < 0.001). Whereas BV was a rare event, AV was frequent and substantially improved during treatment (p < 0.01). While at entry most patients had moderate or severe AV, after maintenance therapy no patient except one had AV. The number of leukocytes dropped dramatically from a score of 1.78 ± 0.70 to 1.06 ± 0.25 which was consistent till the end of the study (p < 0.01). Parabasal cells dropped from a score of 3.4 ± 0.64 at entry to 1.3 ± 0.60 at the final visit (p trend < 0.01). Starting from a low rate of Candida colonisation of 2/14 (14%), a sudden rise to 7/16 (44%) occurred after 2 weeks, to return back to base levels at subsequent visits. The vaginal use of ultra-low dose estriol and lactobacilli results in rapid and enduring improvement of all markers of the vaginal microflora and epithelial vaginal cell quality in women with breast cancer on AI with dyspareunia. Candida may develop soon after its use, but rapidly disappears again upon their prolonged use. Due to its excellent safety profiles and clinical efficacy we recommend

  14. Androgen Triggers the Pro-Migratory CXCL12/CXCR4 Axis in AR-Positive Breast Cancer Cell Lines: Underlying Mechanism and Possible Implications for the Use of Aromatase Inhibitors in Breast Cancer.

    PubMed

    Azariadis, Kalliopi; Kiagiadaki, Fotini; Pelekanou, Vasiliki; Bempi, Vasiliki; Alexakis, Kostas; Kampa, Marilena; Tsapis, Andreas; Castanas, Elias; Notas, George

    2017-01-01

    Reports regarding the role of androgen in breast cancer (BC) are conflicting. Some studies suggest that androgen could lead to undesirable responses in the presence of certain BC tumor characteristics. We have shown that androgen induces C-X-C motif chemokine 12 (CXCL12) in BC cell lines. Our aim was to identify the mechanisms regulating the phenotypic effects of androgen-induced CXCL12 on Androgen Receptor (AR) positive BC cell lines. We analyzed the expression of CXCL12 and its receptors with qPCR and ELISA and the role of Nuclear Receptor Coactivator 1 (NCOA1) in this effect. AR effects on the CXCL12 promoter was studied via Chromatin-immunoprecipitation. We also analyzed publically available data from The Cancer Genome Atlas to verify AR-CXCL12 interactions and to identify the effect or Aromatase Inhibitors (AI) therapy on CXCL12 expression and disease progression in AR positive cases. CXCL12 induction occurs only in AR-positive BC cell lines, possibly via an Androgen Response Element, upstream of the CXCL12 promoter. The steroid receptor co-regulator NCOA1 is critical for this effect. Androgen only induced the motility of p53-mutant BC cells T47D cells via upregulation of CXCR4 expression while they had no effect on wild-type p53 MCF-7 cells. Loss of CXCR4 expression and depletion of CXCL12 abolished the effect of androgen in T47D cells while inhibition of p53 expression in MCF-7 cells made them responsive to androgen and increased their motility in the presence to androgen. Patients with estrogen receptor positive (ER+)/AR+ BC treated with AIs were at increased risk of disease progression compared to ER+/AR+ non-AI treated and ER+/AR- AI treated cases. AIs may lead to unfavorable responses in some ER/AR positive BC cases, especially in patients with AR+, p53 mutant tumors. © 2017 The Author(s). Published by S. Karger AG, Basel.

  15. Appetitive and consummatory sexual and agonistic behaviour elicits FOS expression in aromatase and vasotocin neurones within the preoptic area and bed nucleus of the stria terminalis of male domestic chickens.

    PubMed

    Xie, J; Kuenzel, W J; Sharp, P J; Jurkevich, A

    2011-03-01

    Some components of male sexual and agonistic behaviours are considered to be regulated by the same neurocircuitry in the medial preoptic nucleus (POM) and the medial portion of bed nucleus of the stria terminalis (BSTM). To better understand this neurocircuitry, numbers of aromatase- (ARO) or arginine vasotocin- (AVT) immunoreactive (ir) neurones expressing immediate early gene protein FOS were compared in the POM and BSTM of male chickens following sexual or agonistic behaviours. Observations were made on males showing: (i) appetitive (courtship) and consummatory (copulation) sexual behaviours; (ii) only appetitive sexual behaviour, or (iii) displaying agonistic behaviour toward other males. Control males were placed on their own in the observation pen, or only handled. In the POM, appetitive sexual behaviour increased ARO+FOS colocalisation, whereas agonistic behaviour decreased the number of visible ARO-ir cells. In the dorsolateral subdivision of BSTM (BSTM1), appetitive sexual behaviour also increased ARO+FOS colocalisation, although the numbers of visible ARO-ir and AVT-ir cells were not altered by sexual or agonistic behaviours. In the ventromedial BSTM (BSTM2), appetitive sexual behaviour increased ARO+FOS and AVT+FOS colocalisation, and all behaviours decreased the number of visible ARO-ir cells, particularly in males expressing consummatory sexual behaviour. Positive correlations were found between numbers of cells with ARO+FOS and AVT+FOS colocalisation in both subdivisions of the BSTM. Waltzing frequency was positively correlated with ARO+FOS colocalisation in the lateral POM, and in both subdivisions of the BSTM in males expressing sexual behaviour. Waltzing frequency in males expressing agonistic behaviour was negatively correlated with the total number of visible ARO-ir cells in the lateral POM and BSTM2. These observations suggest a key role for ARO and AVT neurones in BSTM2 in the expression of appetitive sexual behaviour, and differential roles

  16. Phase III, Randomized Study of Dual Human Epidermal Growth Factor Receptor 2 (HER2) Blockade With Lapatinib Plus Trastuzumab in Combination With an Aromatase Inhibitor in Postmenopausal Women With HER2-Positive, Hormone Receptor-Positive Metastatic Breast Cancer: ALTERNATIVE.

    PubMed

    Johnston, Stephen R D; Hegg, Roberto; Im, Seock-Ah; Park, In Hae; Burdaeva, Olga; Kurteva, Galina; Press, Michael F; Tjulandin, Sergei; Iwata, Hiroji; Simon, Sergio D; Kenny, Sarah; Sarp, Severine; Izquierdo, Miguel A; Williams, Lisa S; Gradishar, William J

    2018-03-10

    Purpose Human epidermal growth factor receptor 2 (HER2) targeting plus endocrine therapy (ET) improved clinical benefit in HER2-positive, hormone receptor (HR)-positive metastatic breast cancer (MBC) versus ET alone. Dual HER2 blockade enhances clinical benefit versus single HER2 blockade. The ALTERNATIVE study evaluated the efficacy and safety of dual HER2 blockade plus aromatase inhibitor (AI) in postmenopausal women with HER2-positive/HR-positive MBC who received prior ET and prior neo(adjuvant)/first-line trastuzumab (TRAS) plus chemotherapy. Methods Patients were randomly assigned (1:1:1) to receive lapatinib (LAP) + TRAS + AI, TRAS + AI, or LAP + AI. Patients for whom chemotherapy was intended were excluded. The primary end point was progression-free survival (PFS; investigator assessed) with LAP + TRAS + AI versus TRAS + AI. Secondary end points were PFS (comparison of other arms), overall survival, overall response rate, clinical benefit rate, and safety. Results Three hundred fifty-five patients were included in this analysis: LAP + TRAS + AI (n = 120), TRAS + AI (n = 117), and LAP + AI (n = 118). Baseline characteristics were balanced. The study met its primary end point; superior PFS was observed with LAP + TRAS + AI versus TRAS + AI (median PFS, 11 v 5.7 months; hazard ratio, 0.62; 95% CI, 0.45 to 0.88; P = .0064). Consistent PFS benefit was observed in predefined subgroups. Overall response rate, clinical benefit rate, and overall survival also favored LAP + TRAS + AI. The median PFS with LAP + AI versus TRAS + AI was 8.3 versus 5.7 months (hazard ratio, 0.71; 95% CI, 0.51 to 0.98; P = .0361). Common adverse events (AEs; ≥ 15%) with LAP + TRAS + AI, TRAS + AI, and LAP + AI were diarrhea (69%, 9%, and 51%, respectively), rash (36%, 2%, and 28%, respectively), nausea (22%, 9%, and 22%, respectively), and paronychia (30%, 0%, and 15%, respectively), mostly grade 1 or 2. Serious AEs were reported similarly across the three groups, and AEs leading to

  17. Ki67 Proliferation Index as a Tool for Chemotherapy Decisions During and After Neoadjuvant Aromatase Inhibitor Treatment of Breast Cancer: Results From the American College of Surgeons Oncology Group Z1031 Trial (Alliance)

    PubMed Central

    Ellis, Matthew J.; Suman, Vera J.; Hoog, Jeremy; Goncalves, Rodrigo; Sanati, Souzan; Creighton, Chad J.; DeSchryver, Katherine; Crouch, Erika; Brink, Amy; Watson, Mark; Luo, Jingqin; Tao, Yu; Barnes, Michael; Dowsett, Mitchell; Budd, G. Thomas; Winer, Eric; Silverman, Paula; Esserman, Laura; Carey, Lisa; Ma, Cynthia X.; Unzeitig, Gary; Pluard, Timothy; Whitworth, Pat; Babiera, Gildy; Guenther, J. Michael; Dayao, Zoneddy; Ota, David; Leitch, Marilyn; Olson, John A.; Allred, D. Craig; Hunt, Kelly

    2017-01-01

    Purpose To determine the pathologic complete response (pCR) rate in estrogen receptor (ER) –positive primary breast cancer triaged to chemotherapy when the protein encoded by the MKI67 gene (Ki67) level was > 10% after 2 to 4 weeks of neoadjuvant aromatase inhibitor (AI) therapy. A second objective was to examine risk of relapse using the Ki67-based Preoperative Endocrine Prognostic Index (PEPI). Methods The American College of Surgeons Oncology Group (ACOSOG) Z1031A trial enrolled postmenopausal women with stage II or III ER-positive (Allred score, 6 to 8) breast cancer whose treatment was randomly assigned to neoadjuvant AI therapy with anastrozole, exemestane, or letrozole. For the trial ACOSOG Z1031B, the protocol was amended to include a tumor Ki67 determination after 2 to 4 weeks of AI. If the Ki67 was > 10%, patients were switched to neoadjuvant chemotherapy. A pCR rate of > 20% was the predefined efficacy threshold. In patients who completed neoadjuvant AI, stratified Cox modeling was used to assess whether time to recurrence differed by PEPI = 0 score (T1 or T2, N0, Ki67 < 2.7%, ER Allred > 2) versus PEPI > 0 disease. Results Only two of the 35 patients in ACOSOG Z1031B who were switched to neoadjuvant chemotherapy experienced a pCR (5.7%; 95% CI, 0.7% to 19.1%). After 5.5 years of median follow-up, four (3.7%) of the 109 patients with a PEPI = 0 score relapsed versus 49 (14.4%) of 341 of patients with PEPI > 0 (recurrence hazard ratio [PEPI = 0 v PEPI > 0], 0.27; P = .014; 95% CI, 0.092 to 0.764). Conclusion Chemotherapy efficacy was lower than expected in ER-positive tumors exhibiting AI-resistant proliferation. The optimal therapy for these patients should be further investigated. For patients with PEPI = 0 disease, the relapse risk over 5 years was only 3.6% without chemotherapy, supporting the study of adjuvant endocrine monotherapy in this group. These Ki67 and PEPI triage approaches are being definitively studied in the ALTERNATE trial (Alternate

  18. Ki67 Proliferation Index as a Tool for Chemotherapy Decisions During and After Neoadjuvant Aromatase Inhibitor Treatment of Breast Cancer: Results From the American College of Surgeons Oncology Group Z1031 Trial (Alliance).

    PubMed

    Ellis, Matthew J; Suman, Vera J; Hoog, Jeremy; Goncalves, Rodrigo; Sanati, Souzan; Creighton, Chad J; DeSchryver, Katherine; Crouch, Erika; Brink, Amy; Watson, Mark; Luo, Jingqin; Tao, Yu; Barnes, Michael; Dowsett, Mitchell; Budd, G Thomas; Winer, Eric; Silverman, Paula; Esserman, Laura; Carey, Lisa; Ma, Cynthia X; Unzeitig, Gary; Pluard, Timothy; Whitworth, Pat; Babiera, Gildy; Guenther, J Michael; Dayao, Zoneddy; Ota, David; Leitch, Marilyn; Olson, John A; Allred, D Craig; Hunt, Kelly

    2017-04-01

    Purpose To determine the pathologic complete response (pCR) rate in estrogen receptor (ER) -positive primary breast cancer triaged to chemotherapy when the protein encoded by the MKI67 gene (Ki67) level was > 10% after 2 to 4 weeks of neoadjuvant aromatase inhibitor (AI) therapy. A second objective was to examine risk of relapse using the Ki67-based Preoperative Endocrine Prognostic Index (PEPI). Methods The American College of Surgeons Oncology Group (ACOSOG) Z1031A trial enrolled postmenopausal women with stage II or III ER-positive (Allred score, 6 to 8) breast cancer whose treatment was randomly assigned to neoadjuvant AI therapy with anastrozole, exemestane, or letrozole. For the trial ACOSOG Z1031B, the protocol was amended to include a tumor Ki67 determination after 2 to 4 weeks of AI. If the Ki67 was > 10%, patients were switched to neoadjuvant chemotherapy. A pCR rate of > 20% was the predefined efficacy threshold. In patients who completed neoadjuvant AI, stratified Cox modeling was used to assess whether time to recurrence differed by PEPI = 0 score (T1 or T2, N0, Ki67 < 2.7%, ER Allred > 2) versus PEPI > 0 disease. Results Only two of the 35 patients in ACOSOG Z1031B who were switched to neoadjuvant chemotherapy experienced a pCR (5.7%; 95% CI, 0.7% to 19.1%). After 5.5 years of median follow-up, four (3.7%) of the 109 patients with a PEPI = 0 score relapsed versus 49 (14.4%) of 341 of patients with PEPI > 0 (recurrence hazard ratio [PEPI = 0 v PEPI > 0], 0.27; P = .014; 95% CI, 0.092 to 0.764). Conclusion Chemotherapy efficacy was lower than expected in ER-positive tumors exhibiting AI-resistant proliferation. The optimal therapy for these patients should be further investigated. For patients with PEPI = 0 disease, the relapse risk over 5 years was only 3.6% without chemotherapy, supporting the study of adjuvant endocrine monotherapy in this group. These Ki67 and PEPI triage approaches are being definitively studied in the ALTERNATE trial (Alternate

  19. Nuclear translocation of phosphorylated STAT3 regulates VEGF-A-induced lymphatic endothelial cell migration and tube formation

    SciTech Connect

    Okazaki, Hideki; Tokumaru, Sho; Hanakawa, Yasushi

    2011-09-02

    Highlights: {yields} VEGF-A enhanced lymphatic endothelial cell migration and increased tube formation. {yields} VEGF-A treated lymphatic endothelial cell showed activation of STAT3. {yields} Dominant-negative STAT3 inhibited VEGF-A-induced lymphatic endothelial cell migration and tube formation. -- Abstract: Vascular endothelial growth factor (VEGF) is an endothelial cell-specific growth factor that regulates endothelial functions, and signal transducers and activators of transcription (STATs) are known to be important during VEGF receptor signaling. The aim of this study was to determine whether STAT3 regulates VEGF-induced lymphatic endothelial cell (LEC) migration and tube formation. VEGF-A (33 ng/ml) enhanced LEC migration by 2-fold and increased tube lengthmore » by 25% compared with the control, as analyzed using a Boyden chamber and Matrigel assay, respectively. Western blot analysis and immunostaining revealed that VEGF-A induced the nuclear translocation of phosphorylated STAT3 in LECs, and this translocation was blocked by the transfection of LECs with an adenovirus vector expressing a dominant-negative mutant of STAT3 (Ax-STAT3F). Transfection with Ax-STAT3F also almost completely inhibited VEGF-A-induced LEC migration and tube formation. These results indicate that STAT3 is essential for VEGF-A-induced LEC migration and tube formation and that STAT3 regulates LEC functions.« less

  20. Therapeutic efficacy of DL-alpha-lipoic acid on cyclosporine A induced renal alterations.

    PubMed

    Amudha, Ganapathy; Josephine, Anthony; Mythili, Yenjerla; Sundarapandiyan, Rajaguru; Varalakshmi, Palaninathan

    2007-10-01

    The present study was designed to evaluate the possible beneficial effect of lipoic acid in preventing the renal damage induced by cyclosporine A in rats. Male albino rats of Wistar strain were divided into four groups and treated as follows. Two groups received cyclosporine A by oral gavage (25 mg/kg/body weight) for 21 days to induce nephrotoxicity, one of which simultaneously received lipoic acid treatment (20 mg/kg body weight) for 21 days. A vehicle (olive oil) and a lipoic acid drug control were also included. Cyclosporine A induced renal damage was evident from the decreased activities of tissue marker enzymes (alkaline phosphatase, acid phosphatase, lactate dehydrogenase, aspartate transaminase and alanine transaminase) and decreased activities of ATPases (Na+, K+-ATPase, Ca2+-ATPase and Mg2+ ATPase). An apparent increase in the levels of serum constituents (urea, uric acid and creatinine) and urinary marker enzymes (N-acetyl-beta-D-glucosaminidase, beta-glucosidase, beta-galactosidase, cathepsin-D and gamma-glutamyl transpeptidase) along with significant decline in creatinine clearance were seen in the cyclosporine treated rats, which was reversed upon treatment with lipoic acid. Ultrastructural observations were also in agreement with the above abnormal changes. Lipoic acid effectively reverted these abnormal biochemical changes and minimized the morphological lesions in renal tissue. Hence, this study clearly exemplifies that lipoic acid might be an ideal choice against cyclosporine A induced cellular abnormalities.

  1. Epigallocatechin-3-gallate (EGCG) attenuates concanavalin A-induced hepatic injury in mice.

    PubMed

    Liu, Dongmei; Zhang, Xiaoli; Jiang, Li; Guo, Yun; Zheng, Changqing

    2014-05-01

    (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenolic compound present in green tea and has been shown to possess anti-inflammatory and anti-oxidative properties. In this study, we investigated the protective effects of EGCG against concanavalin A (ConA)-induced liver injury and the underlying mechanisms. EGCG (5 mg/kg) was administered orally by gavage to mice twice daily for 10 days before an intravenous injection of ConA. We found that EGCG effectively rescued lethality, improved hepatic pathological damage, and decreased serum levels of alanine aminotransaminase (ALT) in ConA-challenged mice. Furthermore, EGCG also significantly prevented the release of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-4, and IL-6 in serum, reduced malondialdehyde (MDA) levels, and restored glutathione (GSH) content and superoxide dismutase (SOD) activity in liver tissues from ConA-challenged mice. Finally, nuclear factor (NF)-κB activation and expression levels of Toll-like receptor (TLR) 2, TLR4 and TLR9 protein in liver tissues were significantly inhibited by EGCG pretreatment. Taken together, our data suggest that EGCG possesses hepatoprotective properties against ConA-induced liver injury through its anti-inflammatory and anti-oxidant actions. Copyright © 2013 Elsevier GmbH. All rights reserved.

  2. Fulvestrant plus anastrozole or placebo versus exemestane alone after progression on non-steroidal aromatase inhibitors in postmenopausal patients with hormone-receptor-positive locally advanced or metastatic breast cancer (SoFEA): a composite, multicentre, phase 3 randomised trial.

    PubMed

    Johnston, Stephen Rd; Kilburn, Lucy S; Ellis, Paul; Dodwell, David; Cameron, David; Hayward, Larry; Im, Young-Hyuck; Braybrooke, Jeremy P; Brunt, A Murray; Cheung, Kwok-Leung; Jyothirmayi, Rema; Robinson, Anne; Wardley, Andrew M; Wheatley, Duncan; Howell, Anthony; Coombes, Gill; Sergenson, Nicole; Sin, Hui-Jung; Folkerd, Elizabeth; Dowsett, Mitch; Bliss, Judith M

    2013-09-01

    The optimum endocrine treatment for postmenopausal women with advanced hormone-receptor-positive breast cancer that has progressed on non-steroidal aromatase inhibitors (NSAIs) is unclear. The aim of the SoFEA trial was to assess a maximum double endocrine targeting approach with the steroidal anti-oestrogen fulvestrant in combination with continued oestrogen deprivation. In a composite, multicentre, phase 3 randomised controlled trial done in the UK and South Korea, postmenopausal women with hormone-receptor-positive breast cancer (oestrogen receptor [ER] positive, progesterone receptor [PR] positive, or both) were eligible if they had relapsed or progressed with locally advanced or metastatic disease on an NSAI (given as adjuvant for at least 12 months or as first-line treatment for at least 6 months). Additionally, patients had to have adequate organ function and a WHO performance status of 0-2. Participants were randomly assigned (1:1:1) to receive fulvestrant (500 mg intramuscular injection on day 1, followed by 250 mg doses on days 15 and 29, and then every 28 days) plus daily oral anastrozole (1 mg); fulvestrant plus anastrozole-matched placebo; or daily oral exemestane (25 mg). Randomisation was done with computer-generated permuted blocks, and stratification was by centre and previous use of an NSAI as adjuvant treatment or for locally advanced or metastatic disease. Participants and investigators were aware of assignment to fulvestrant or exemestane, but not of assignment to anastrozole or placebo. The primary endpoint was progression-free survival (PFS). Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, numbers NCT00253422 (UK) and NCT00944918 (South Korea). Between March 26, 2004, and Aug 6, 2010, 723 patients underwent randomisation: 243 were assigned to receive fulvestrant plus anastrozole, 231 to fulvestrant plus placebo, and 249 to exemestane. Median PFS was 4·4 months (95% CI 3·4-5·4) in patients assigned to

  3. Treatment with Ruta graveolens 5CH and Rhus toxicodendron 9CH may reduce joint pain and stiffness linked to aromatase inhibitors in women with early breast cancer: results of a pilot observational study.

    PubMed

    Karp, Jean-Claude; Sanchez, Carole; Guilbert, Philippe; Mina, William; Demonceaux, Antoine; Curé, Hervé

    2016-11-01

    To determine the possible effect of two homeopathic medicines, Ruta graveolens 5CH and Rhus toxicodendron 9CH, in the prevention of aromatase inhibitor (AI) associated joint pain and/or stiffness in women with early, hormone-receptor positive, breast cancer. This prospective, unrandomized observational study was carried out between April and October 2014. Women were recruited in two groups, according to which of the two study centres they attended: one receiving homeopathy in addition to standard treatment (group H) and a control group, receiving standard treatment (group C). All women were treated with an AI. In addition, women in group H also took Ruta graveolens 5CH and Rhus toxicodendron 9CH (5 granules, twice a day) up to 7 days before starting AI treatment. The homeopathic medicines were continued for 3 months. Demographic and clinical data were recorded using a self-assessment questionnaire at inclusion (T0) and 3 months (T3). Primary evaluation criteria were the evolution of scores for joint pain and stiffness, the impact of pain on sleep and analgesic consumption in the two groups after 3 months of treatment. Forty patients (mean age 64.9±8.1 years) were recruited, 20 in each group. Two-thirds of the patients had joint pain before starting AI treatment. There was a significant difference in the evolution of mean composite pain score between T0 and T3 in the two groups (-1.3 in group H vs. +3.4 in group C; p=0.0001). The individual components of the pain score (frequency, intensity and number of sites of pain) also decreased significantly in group H. Nine patients in group C (45%) vs. 1 (5%) in group H increased their analgesic consumption between T0 and T3 (p=0.0076). After 3 months of treatment, joint pain had a worse impact on sleep in patients in group C (35% vs. 0% of patients; p=0.0083). The differences observed in the evolution of morning and daytime stiffness between the two groups were smaller (p=0.053 and p=0.33, respectively), with the exception

  4. Hypervitaminosis A-induced hepatic fibrosis in a cat.

    PubMed

    Guerra, Juliana M; Daniel, Alexandre G T; Aloia, Thiago P A; de Siqueira, Adriana; Fukushima, André R; Simões, Denise M N; Reche-Júior, Archivaldo; Cogliati, Bruno

    2014-03-01

    The excessive intake of vitamin A in the form of vitamin concentrate, supplement or vitamin-rich liver can result in hypervitaminosis A in man and animals. Although osteopathologies resulting from chronic vitamin A intoxication in cats are well characterized, no information is available concerning feline hypervitaminosis A-induced liver disease. We report the first case of hepatic stellate cell lipidosis and hepatic fibrosis in a domestic cat that had been fed a diet based on raw beef liver. Radiographic examination revealed exostoses and ankylosis between vertebrae C1 and T7, compatible with deforming cervical spondylosis. Necropsy showed a slightly enlarged and light yellow to bronze liver. Microscopic and ultrastructural analyses of liver tissues revealed diffuse and severe liver fibrosis associated with hepatic stellate cell hyperplasia and hypertrophy. These cells showed immunopositive staining for α-smooth muscle actin and desmin markers. The necropsy findings of chronic liver disease coupled with osteopathology supported the diagnosis of hypervitaminosis A. As in human hepatology, if there is dietary evidence to support increased intake of vitamin A, then hypervitaminosis A should be considered in the differential diagnosis of chronic liver disease in cats.

  5. Caspase-8 acts as a key upstream executor of mitochondria during justicidin A-induced apoptosis in human hepatoma cells.

    PubMed

    Su, Chun-Li; Huang, Lynn L H; Huang, Li-Min; Lee, Jenq-Chang; Lin, Chun-Nan; Won, Shen-Jeu

    2006-05-29

    Justicia procumbens is a traditional Taiwanese herbal remedy used to treat fever, pain, and cancer. Justicidin A, isolated from Justicia procumbens, has been reported to suppress in vitro growth of several tumor cell lines as well as hepatoma cells. In this study, justicidin A activated caspase-8 to increase tBid, disrupted mitochondrial membrane potential (Delta psi(m)), and caused the release of cytochrome c and Smac/DIABLO in Hep 3B and Hep G2 cells. Justicidin A also reduced Bcl-x(L) and increased Bax and Bak in mitochondria. Caspase-8 inhibitor (Z-IETD) attenuated the justicidin A-induced disruption of Delta psi(m). Growth of Hep 3B implanted in NOD-SCID mice was suppressed significantly by oral justicidin A (20 mg/kg/day). These results indicate that justicidin A-induced apoptosis in these cells proceeds via caspase-8 and is followed by mitochondrial disruption.

  6. Relevance of anti-inflammatory and antioxidant activities of exemestane and synergism with sulforaphane for disease prevention

    PubMed Central

    Liu, Hua; Talalay, Paul

    2013-01-01

    Exemestane (6-methyleneandrosta-1,4-diene-3,17-dione) is a synthetic steroidal inhibitor of the aromatase reaction that catalyzes the terminal and rate-limiting step of the biosynthesis of estrogens. It is active clinically in preventing, delaying progression of, and treating mammary cancers, many of which are estrogen receptor-positive. A striking feature of the structure of exemestane is an extended system of conjugated Michael reaction functions, which is also characteristic of inducers of a broad network of chemoprotective genes regulated by the Keap1 (Kelch-like ECA-associated protein)/Nrf2 (nuclear factor E2-related factor 2)/ARE (antioxidant response element) signaling system. These genes are largely involved in xenobiotic metabolism and antioxidative and anti-inflammatory protection, as well as the synthesis and reduction of glutathione. We show here that exemestane transcriptionally activates NAD(P)H:quinone oxidoreductase 1 (NQO1) and heme oxygenase 1 (HO-1), typical chemoprotective gene products, in a wide variety of mouse, rat, and human cells. It protects several cell lines against oxidative toxicity of tert-butyl hydroperoxide and 4-hydroxynonenal, against free radical damage arising from hypoxia–reoxygenation, and against UVA radiation damage. Exemestane also inhibits the inflammatory increases in inducible nitric oxide synthase (iNOS) in mouse macrophages exposed to LPS (lipopolysaccharide), thereby resembling the isothiocyanate sulforaphane derived from broccoli. Remarkably, combinations of exemestane and sulforaphane act highly synergistically, and this property is also displayed by several other phytochemicals. Thus, exemestane has a wide range of previously unrecognized protective activities, probably unrelated to aromatase inhibition. Its potential for reducing the risk, not only of breast cancer, but also of other chronic diseases that arise from inflammation, oxidative stress, and DNA-damaging electrophiles, requires exploration

  7. Relevance of anti-inflammatory and antioxidant activities of exemestane and synergism with sulforaphane for disease prevention.

    PubMed

    Liu, Hua; Talalay, Paul

    2013-11-19

    Exemestane (6-methyleneandrosta-1,4-diene-3,17-dione) is a synthetic steroidal inhibitor of the aromatase reaction that catalyzes the terminal and rate-limiting step of the biosynthesis of estrogens. It is active clinically in preventing, delaying progression of, and treating mammary cancers, many of which are estrogen receptor-positive. A striking feature of the structure of exemestane is an extended system of conjugated Michael reaction functions, which is also characteristic of inducers of a broad network of chemoprotective genes regulated by the Keap1 (Kelch-like ECA-associated protein)/Nrf2 (nuclear factor E2-related factor 2)/ARE (antioxidant response element) signaling system. These genes are largely involved in xenobiotic metabolism and antioxidative and anti-inflammatory protection, as well as the synthesis and reduction of glutathione. We show here that exemestane transcriptionally activates NAD(P)H:quinone oxidoreductase 1 (NQO1) and heme oxygenase 1 (HO-1), typical chemoprotective gene products, in a wide variety of mouse, rat, and human cells. It protects several cell lines against oxidative toxicity of tert-butyl hydroperoxide and 4-hydroxynonenal, against free radical damage arising from hypoxia-reoxygenation, and against UVA radiation damage. Exemestane also inhibits the inflammatory increases in inducible nitric oxide synthase (iNOS) in mouse macrophages exposed to LPS (lipopolysaccharide), thereby resembling the isothiocyanate sulforaphane derived from broccoli. Remarkably, combinations of exemestane and sulforaphane act highly synergistically, and this property is also displayed by several other phytochemicals. Thus, exemestane has a wide range of previously unrecognized protective activities, probably unrelated to aromatase inhibition. Its potential for reducing the risk, not only of breast cancer, but also of other chronic diseases that arise from inflammation, oxidative stress, and DNA-damaging electrophiles, requires exploration, particularly

  8. In vitro and in vivo estrogenic activity of BPA, BPF and BPS in zebrafish-specific assays.

    PubMed

    Le Fol, Vincent; Aït-Aïssa, Selim; Sonavane, Manoj; Porcher, Jean-Marc; Balaguer, Patrick; Cravedi, Jean-Pierre; Zalko, Daniel; Brion, François

    2017-08-01

    Bisphenol A (BPA) is a widely used chemical that has been extensively studied as an endocrine-disrupting chemical (EDC). Other bisphenols sharing close structural features with BPA, are increasingly being used as alternatives, increasing the need to assess associated hazards to the endocrine system. In the present study, the estrogenic activity of BPA, bisphenol S (BPS) and bisphenol F (BPF) was assessed by using a combination of zebrafish-specific mechanism-based in vitro and in vivo assays. The three bisphenols were found to efficiently transactivate all zebrafish estrogen receptor (zfER) subtypes in zebrafish hepatic reporter cell lines (ZELH-zfERs). BPA was selective for zfERα while BPS and BPF were slightly more potent on zfERβ subtypes. We further documented the estrogenic effect in vivo by quantifying the expression of brain aromatase using a transgenic cyp19a1b-GFP zebrafish embryo assay. All three bisphenols induced GFP in a concentration-dependent manner. BPS only partially induced brain aromatase at the highest tested concentrations (>30µM) while BPA and BPF strongly induced GFP, in an ER-dependent manner, at 1-10µM. Furthermore, we show that BPF strongly induced vitellogenin synthesis in adult male zebrafish. Overall, this study demonstrates the estrogenic activity of BPA, BPF and BPS in different cell- and tissue-contexts and at different stages of development. Differences between in vitro and in vivo responses are discussed in light of selective ER activation and the fate of the compounds in the models. This study confirms the relevance of combining cellular and whole-organism bioassays in a unique model species for the hazard assessment of candidate EDCs. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Is there a role for estrogen activity assays? Recombinant cell bioassay for estrogen: Development and applications.

    PubMed

    Klein, Karen Oerter

    2015-07-01

    There are many questions which cannot be answered without a very sensitive estradiol assay. A recombinant cell bioassay (RCBA) for estradiol was developed in 1994. The sensitivity of the bioassay is 0.02-0.2 pg/ml (0.07-0.7 pmol/L), more than 20 times more sensitive than commercial RIAs and 10 times more sensitive than newer mass spectrometry assays. The RCBA for estradiol opened the door to study low levels of estradiol equivalents (EE) across the physiological spectrum of life from prepubertal children through menopause and across the spectrum from normal physiology, in boys as well as girls, to pathology, including: premature thelarche; estradiol suppression in children treated with GnRH analogues for precocious puberty; aromatase inhibition in boys with growth hormone deficiency; the differences between oral and transdermal routes of estrogen administration in girls with Turner's syndrome; women with breast cancer treated with aromatase inhibitors; and women with urogenital atrophy treated with low dose vaginal estrogen. A bioassay also allows study of endocrine disruptors, like phytoestrogens and other environmental compounds, which are relevant to public health and alternative medicine options. This paper reviews the assay and the last 20 years of applications. A bioassay for estrogen has a role because measuring biological effect is theoretically useful, increasing the understanding of physiology in addition to biochemical levels, giving different information than other assays, and opening the door to measure very low levels of estrogen activity in both humans and the environment. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Antifibrotic mechanism of deferoxamine in concanavalin A induced-liver fibrosis: Impact on interferon therapy.

    PubMed

    Darwish, Samar F; El-Bakly, Wesam M; El-Naga, Reem N; Awad, Azza S; El-Demerdash, Ebtehal

    2015-11-01

    Iron-overload is a well-known factor of hepatotoxicity and liver fibrosis, which found to be a common finding among hepatitis C virus patients and related to interferon resistance. We aimed to elucidate the potential antifibrotic effect of deferoxamine; the main iron chelator, and its additional usefulness to interferon-based therapy in concanavalin A-induced immunological model of liver fibrosis. Rats were treated with deferoxamine and/or pegylated interferon-α for 6 weeks. Hepatotoxicity indices, oxidative stress, inflammatory and liver fibrosis markers were assessed. Concanavalin A induced a significant increase in hepatotoxicity indices and lipid peroxidation accompanied with a significant depletion of total antioxidant capacity, glutathione level and superoxide dismutase activity. Besides, it increased CD4(+) T-cells content and the downstream inflammatory cascades, including NF-κB, TNF-α, iNOS, COX-2, IL-6 and IFN-γ. Furthermore, α-SMA, TGF-β1 and hydroxyproline were increased markedly, which confirmed by histopathology. Treatment with either deferoxamine or pegylated interferon-α alone reduced liver fibrosis markers significantly and improved liver histology. However, some of the hepatotoxicity indices and oxidative stress markers did not improve upon pegylated interferon-α treatment alone, besides the remarkable increase in IL-6. Combination therapy of deferoxamine with pegylated interferon-α further improved all previous markers, ameliorated IL-6 elevation, as well as increased hepcidin expression. In conclusion, our study provides evidences for the potent antifibrotic effects of deferoxamine and the underlying mechanisms that involved attenuating oxidative stress and subsequent inflammatory cascade, as well as the production of profibrogenic factors. Addition of deferoxamine to interferon regimen for HCV patients may offer a promising adjuvant modality to enhance therapeutic response. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Licochalcone A induces apoptosis in KB human oral cancer cells via a caspase-dependent FasL signaling pathway

    PubMed Central

    KIM, JAE-SUNG; PARK, MI-RA; LEE, SOOK-YOUNG; KIM, DO KYOUNG; MOON, SUNG-MIN; KIM, CHUN SUNG; CHO, SEUNG SIK; YOON, GOO; IM, HEE-JEONG; YOU, JAE-SEEK; OH, JI-SU; KIM, SU-GWAN

    2014-01-01

    Licochalcone A (Lico-A) is a natural phenol licorice compound with multiple bioactivities, including anti-inflammatory, anti-microbial, anti-fungal and osteogenesis-inducing properties. In the present study, we investigated the Lico-A-induced apoptotic effects and examined the associated apoptosis pathway in KB human oral cancer cells. Lico-A decreased the number of viable KB oral cancer cells. However, Lico-A did not have an effect on primary normal human oral keratinocytes. In addition, the IC50 value of Lico-A was determined to be ~50 μM following dose-dependent stimulation. KB oral cancer cells stimulated with Lico-A for 24 h showed chromatin condensation by DAPI staining, genomic DNA fragmentation by agarose gel electrophoresis and a gradually increased apoptotic cell population by FACS analysis. These data suggest that Lico-A induces apoptosis in KB oral cancer cells. Additionally, Lico-A-induced apoptosis in KB oral cancer cells was mediated by the expression of factor associated suicide ligand (FasL) and activated caspase-8 and −3 and poly(ADP-ribose) polymerase (PARP). Furthermore, in the KB oral cancer cells co-stimulation with a caspase inhibitor (Z-VAD-fmk) and Lico-A significantly abolished the apoptotic phenomena. Our findings demonstrated that Lico-A-induced apoptosis in KB oral cancer cells involves the extrinsic apoptotic signaling pathway, which involves a caspase-dependent FasL-mediated death receptor pathway. Our data suggest that Lico-A be developed as a chemotherapeutic agent for the management of oral cancer. PMID:24337492

  12. Synaptic Long-Term Potentiation and Depression in the Rat Medial Vestibular Nuclei Depend on Neural Activation of Estrogenic and Androgenic Signals

    PubMed Central

    Scarduzio, Mariangela; Panichi, Roberto; Pettorossi, Vito Enrico; Grassi, Silvarosa

    2013-01-01

    Estrogenic and androgenic steroids can be synthesised in the brain and rapidly modulate synaptic transmission and plasticity through direct interaction with membrane receptors for estrogens (ERs) and androgens (ARs). We used whole cell patch clamp recordings in brainstem slices of male rats to explore the influence of ER and AR activation and local synthesis of 17β-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the long-term synaptic changes induced in the neurons of the medial vestibular nucleus (MVN). Long-term depression (LTD) and long-term potentiation (LTP) caused by different patterns of high frequency stimulation (HFS) of the primary vestibular afferents were assayed under the blockade of ARs and ERs or in the presence of inhibitors for enzymes synthesizing DHT (5α-reductase) and E2 (P450-aromatase) from testosterone (T). We found that LTD is mediated by interaction of locally produced androgens with ARs and LTP by interaction of locally synthesized E2 with ERs. In fact, the AR block with flutamide prevented LTD while did not affect LTP, and the blockade of ERs with ICI 182,780 abolished LTP without influencing LTD. Moreover, the block of P450-aromatase with letrozole not only prevented the LTP induction, but inverted LTP into LTD. This LTD is likely due to the local activation of androgens, since it was abolished under blockade of ARs. Conversely, LTD was still induced in the presence of finasteride the inhibitor of 5α-reductase demonstrating that T is able to activate ARs and induce LTD even when DHT is not synthesized. This study demonstrates a key and opposite role of sex neurosteroids in the long-term synaptic changes of the MVN with a specific role of T-DHT for LTD and of E2 for LTP. Moreover, it suggests that different stimulation patterns can lead to LTD or LTP by specifically activating the enzymes involved in the synthesis of androgenic or estrogenic neurosteroids. PMID:24265837

  13. Synaptic long-term potentiation and depression in the rat medial vestibular nuclei depend on neural activation of estrogenic and androgenic signals.

    PubMed

    Scarduzio, Mariangela; Panichi, Roberto; Pettorossi, Vito Enrico; Grassi, Silvarosa

    2013-01-01

    Estrogenic and androgenic steroids can be synthesised in the brain and rapidly modulate synaptic transmission and plasticity through direct interaction with membrane receptors for estrogens (ERs) and androgens (ARs). We used whole cell patch clamp recordings in brainstem slices of male rats to explore the influence of ER and AR activation and local synthesis of 17β-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the long-term synaptic changes induced in the neurons of the medial vestibular nucleus (MVN). Long-term depression (LTD) and long-term potentiation (LTP) caused by different patterns of high frequency stimulation (HFS) of the primary vestibular afferents were assayed under the blockade of ARs and ERs or in the presence of inhibitors for enzymes synthesizing DHT (5α-reductase) and E2 (P450-aromatase) from testosterone (T). We found that LTD is mediated by interaction of locally produced androgens with ARs and LTP by interaction of locally synthesized E2 with ERs. In fact, the AR block with flutamide prevented LTD while did not affect LTP, and the blockade of ERs with ICI 182,780 abolished LTP without influencing LTD. Moreover, the block of P450-aromatase with letrozole not only prevented the LTP induction, but inverted LTP into LTD. This LTD is likely due to the local activation of androgens, since it was abolished under blockade of ARs. Conversely, LTD was still induced in the presence of finasteride the inhibitor of 5α-reductase demonstrating that T is able to activate ARs and induce LTD even when DHT is not synthesized. This study demonstrates a key and opposite role of sex neurosteroids in the long-term synaptic changes of the MVN with a specific role of T-DHT for LTD and of E2 for LTP. Moreover, it suggests that different stimulation patterns can lead to LTD or LTP by specifically activating the enzymes involved in the synthesis of androgenic or estrogenic neurosteroids.

  14. Evaluation and comparison of bisphenol A analog activity ...

    EPA Pesticide Factsheets

    Bisphenol A (BPA) is used in consumer products and industrial applications, primarily in plastics, and has been detected in the environment, human urine, blood, and breast milk. Mainly studied as an endocrine disruptor, other toxicities, including obesity, metabolic conditions such as diabetes, and neurodevelopmental effects have also been associated with exposure to BPA, indicating that its effects may not be limited to estrogenicity. In addition, a number of BPA analogs are in use and may exhibit other additional toxicities. To address these unknowns, we examined the bioactivity of 21 BPA analogs across a selection of ToxCast/Tox21 assays grouped by 7 gene sets including estrogen receptor (ER), androgen receptor (AR), thyroid receptor (TR), peroxisome proliferator-activated receptor (PPAR), pregnane x receptor (PXR), aromatase (AROM), and aryl hydrocarbon receptor (AHR). The most active compounds were bisphenol AF (BPAF) (ER, AR, AROM, AHR), bisphenol A glycidyl methacrylate (TR), 3,3’,5,5’-tetrabromobisphenol A (PPAR) and bisphenol B (BPB) (PXR). We used these data to produce toxicological prioritization index (ToxPi) scores and images to integrate and visually compare the toxicity profiles across all gene sets. The compounds with highest ToxPi scores were BPAF, BPA and BPB. We also mapped the intended gene targets for all ToxCast assays to their associated KEGG BRITE protein families in order to characterize their toxicity profiles on a broader spectr

  15. Hepatoprotective Effect of Wedelolactone against Concanavalin A-Induced Liver Injury in Mice.

    PubMed

    Luo, Qingqiong; Ding, Jieying; Zhu, Liping; Chen, Fuxiang; Xu, Lili

    2018-05-08

    Eclipta prostrata L. is a traditional Chinese herbal medicine that has been used in the treatment of liver diseases. However, its biological mechanisms remain elusive. The current study aimed to investigate the hepatoprotective effect of wedelolactone, a major coumarin ingredient of Eclipta prostrata L., on immune-mediated liver injury. Using the well-established animal model of Concanavalin A (ConA)-induced hepatitis (CIH), we found that pretreatment of mice with wedelolactone markedly reduced both the serum levels of transaminases and the severity of liver damage. We further investigated the mechanisms of the protective effect of wedelolactone. In mice treated with wedelolactone prior to the induction of CIH, increases of serum concentrations of tumor necrosis factor (TNF)-[Formula: see text], interferon (IFN)-[Formula: see text], and interleukin (IL)-6 were dramatically attenuated. Additionally, expressions of the interferon-inducible chemokine (C-X-C motif) ligand 10 gene CXCL10 and intercellular adhesion molecule 1 gene ICAM1 were lower in livers of the treated mice. Moreover, wedelolactone-treated CIH mice exhibited reduced leukocyte infiltration and T-cell activation in liver. Furthermore, wedelolactone suppressed the activity of nuclear factor-kappa B (NF-[Formula: see text]B), a critical transcriptional factor of the above-mentioned inflammatory cytokines by limiting the phosphorylation of I kappa B alpha (I[Formula: see text]B[Formula: see text] and p65. In conclusion, these findings demonstrate the inhibitory potential of wedelolactone in immune-mediated liver injury in vivo, and show that this protection is associated with modulation of the NF-[Formula: see text]B signaling pathway.

  16. CREG1 enhances p16INK4a-induced cellular senescence

    PubMed Central

    Moolmuang, Benchamart

    2011-01-01

    Cellular senescence is an irreversible growth arrest that is activated in normal cells upon shortening of telomere and other cellular stresses. Bypassing cellular senescence is a necessary step for cells to become immortal during oncogenic transformation. During the spontaneous immortalization of Li-Fraumeni Syndrome (LFS) fibroblasts, we found that CREG1 (Cellular Repressor of E1A-stimulated Genes 1) expression was decreased during immortalization and increased in senescence. Moreover, we found that repression of CREG1 expression occurs via an epigenetic mechanism, promoter DNA methylation. Ectopic expression of CREG1 in the immortal LFS cell lines decreases cell proliferation but does not directly induce senescence. We confirmed this in osteosarcoma and fibrosarcoma cancer cell lines, cancers commonly seen in Li-Fraumeni Syndrome. In addition, we found that p16