Association of CYP17, CYP19, CYP1B1, and COMT Polymorphisms with Serum and Urinary Sex Hormone Concentrations in Postmenopausal Women

Women with high circulating estrogen concentrations have an increased risk of breast cancer; thus, it is important to understand factors, including genetic variability, that influence estrogen concentrations. Several genetic polymorphisms that may influence sex hormone concentrations have been identified, including CYP17 (5'-untranslated region T-->C), CYP19 [intron 4 (TTTA)(n = 7-13) and a 3-bp deletion (-3)], CYP1B1 (Val(432)Leu), and COMT (Val(108/158)Met). We examined associations between these polymorphisms and serum concentrations of estrogens, androgens, and sex hormone-binding globulin and urinary concentrations of 2- and 16alpha-hydroxyestrone in 171 postmenopausal women, using data from the prerandomization visit of an exercise clinical trial. Participants were sedentary, not taking hormone therapy, and had a body mass index >24.0. Compared with noncarriers, women carrying two CYP19 7r(-3) alleles had 26% lower estrone (P < 0.001), 19% lower estradiol (P = 0.01), 23% lower free estradiol (P = 0.01), and 22% higher sex hormone-binding globulin concentrations (P = 0.06). Compared with noncarriers, women carrying at least one CYP19 8r allele had 20% higher estrone (P = 0.003), 18% higher estradiol (P = 0.02), and 21% higher free estradiol concentrations (P = 0.01). Women with the COMT Met/Met genotype had 28% higher 2-hydroxyestrone (P = 0.08) and 31% higher 16alpha-hydroxyestrone concentrations (P = 0.02), compared with Val/Val women. Few associations were found for CYP17 and CYP1B1 or with serum androgen concentrations. This study provides further evidence that genetic variation may appreciably alter sex hormone concentrations in postmenopausal women not taking hormone therapy.

Circulating cell-free AR and CYP17A1 copy number variations may associate with outcome of metastatic castration-resistant prostate cancer patients treated with abiraterone

BACKGROUND

This study aimed to investigate copy number variations (CNVs) of CYP17A1 and androgen receptor (AR) genes in serum cell-free DNA collected before starting abiraterone in 53 consecutive patients with castration-resistant prostate cancer (CRPC).

METHODS

Serum DNA was isolated and CNVs were analysed for AR and CYP17A1 genes using Taqman copy number assays. The association between CNVs and progression-free/overall survival (PFS/OS) was evaluated by the Kaplan-Meier method and log-rank test.

RESULTS

Median PFS of patients with AR gene gain was 2.8 vs 9.5 months of non-gained cases (P < 0.0001). Patients with CYP17A1 gene gain had a median PFS of 2.8 months vs 9.2 months in the non-gained patients (P = 0.0014). A lower OS was reported in both cases (AR: P < 0.0001; CYP17A1: P = 0.0085). Multivariate analysis revealed that PSA decline ⩾ 50%, AR and CYP17A1 CNVs were associated with shorter PFS (P < 0.0001, P = 0.0004 and P = 0.0450, respectively), while performance status, PSA decline ⩾ 50%, AR CNV and DNA concentration were associated with OS (P = 0.0021, P = 0.0014, P = 0.0026 and P = 0.0129, respectively).

CONCLUSIONS

CNVs of AR and CYP17A1 genes would appear to be associated with outcome of CRPC patients treated with abiraterone.

Identification by molecular cloning of an autoantigen associated with Addison's disease as steroid 17 alpha-hydroxylase

Idiopathic Addison's disease is characterised by a progressive failure in the synthesis of all classes of steroid hormones and by an immune response against the steroid-producing cells of the adrenal cortex; the nature of the adrenal autoantigens is not known. We have used molecular cloning and sequencing to identify the target antigens. We screened a human fetal adrenal cDNA expression library in lambda gt11 vector with serum samples from patients with Addison's disease as part of the type 1 polyendocrine autoimmunity syndrome. Samples from 3 patients, which had precipitating antibodies against two adrenal proteins detected by immunodiffusion and against five adrenal proteins of molecular mass 55, 48, 43, 39, and 19 kDa as judged by immunoblotting, were used to identify 60 immunoreactive clones. 39 of these were subcloned, inserted into the M13mp10 vector, and sequenced by the dideoxy method or identified by Southern and dot-blot hybridisation. All but 1 of the inserts showed more than 98.8% homology with the published sequence of steroid 17 alpha-hydroxylase. This protein was expressed by insertion of 1 of the clones into the pGEMEX-1 vector. Only serum from patients with Addison's disease and type 1 polyendocrine autoimmunity syndrome that reacted with the 55 kDa adrenal protein recognised the recombinant 17 alpha-hydroxylase protein on immunoblotting. Our results show that one of the key enzymes in steroid biosynthesis, 17 alpha-hydroxylase, is an autoantigen involved in the pathogenesis of adrenocortical failure.

CYP17 inhibition as a hormonal strategy for prostate cancer

Androgen receptor (AR) signaling has a key role in the pathogenesis of prostate cancer. AR gene amplification, AR overexpression, and activating mutations in the AR occur more frequently as castration-resistant prostate cancer (CRPC) evolves, with intratumoral androgen levels remaining sufficient for AR activation despite castration. The source of these androgens might be either adrenal or intratumoral. AR signaling, therefore, remains a valid treatment target for patients with CRPC. CYP17 is a key enzyme for androgen biosynthesis. The imidazole antifungal agent ketoconazole weakly and nonspecifically inhibits CYP17, but remains unlicensed for this indication. Chemists at the Cancer Research UK Centre for Cancer Therapeutics have designed a novel, selective, irreversible inhibitor of CYP17 called abiraterone, which is more than 20 times more potent than ketoconazole. Abiraterone acetate, a prodrug, has undergone phase I assessment, and is rapidly progressing from phase II to phase III trials, in view of its high level of antitumor activity. This agent is safe and well tolerated, and activity profiles suggest that approximately 50% of CRPC remains AR-ligand driven. Other CYP17 inhibitors with alternative mechanisms of action, for example VN/124-1, are in preclinical development. The rationale for and implications of CYP17 inhibition and the CYP17-targeting agents in development are discussed in this Review.

Increased circulating concentrations of parathyroid hormone in healthy, young women consuming a protein-restricted diet

Increasing dietary protein induces hypercalciuria and a negative calcium balance. Despite this, the influence of dietary protein on the parathyroid hormone (PTH) I-a-hydroxylase axis is not well understood. We therefore examined the effect of three amounts of dietary protein: low (0.7 g/kg), medium (1.0 g/kg), and high (2.1 g/kg) on mineral metabolism and the PTH-1-alpha-hydroxylase axis in 16 healthy women aged 26.7 +/- 1.3 y. By day 4, urinary calcium decreased significantly with the low-protein diet and increased significantly with the high-protein diet compared with the medium-protein diet (control). Also by day 4, there were striking elevations in serum PTH and calcitriol [1,25-dihydroxyvitamin D] in subjects consuming the low-protein diet. Serum PTH, by two different assays, was 1.5-2.4 times higher and by day 14 1.6-2.7 times higher during the low-protein diet compared with the medium-protein diet. This was accompanied by a significant increase in both nephrogenous cyclic adenosine monophosphate (cAMP), a sensitive and specific indicator of PTH bioactivity, and serum calcitriol by day 14. In comparison, there were relatively minor changes in the calcitropic hormones with the medium- and high-protein diets. The stimulus for the elevation in PTH induced by protein restriction is unclear, but probably does not involve a simple renal mechanism and could reflect either a decline in intestinal calcium absorption, a reduction of bone turn-over, or both. Our data indicate that dietary protein is a powerful regulator of calcium metabolism. Further study is needed to both clarify the mechanisms by which these changes are induced and to better define the amount of dietary protein that will optimize skeletal health in young women.

The longitudinal study of adrenal maturation during gonadal suppression: evidence that adrenarche is a gradual process

The physical changes that herald the onset of puberty result from the combination of adrenarche and gonadarche. To examine adrenal maturation and associated changes in growth without the confounding effects of changes in the gonadal steroid milieu, we performed a longitudinal study in 14 young girls with idiopathic central precocious puberty during long-term pituitary-gonadal suppression. Beginning at the mean age of 2.9 yr, dehydroepiandrosterone sulfate levels, linear growth, skeletal maturation, body mass index, and secondary sexual development were evaluated at 3- to 6-month intervals for up to 12.3 yr. In 12 of the girls, levels of dehydroepiandrosterone, androstenedione, 17-hydroxypregnenolone, and 17alpha-hydroxyprogesterone were determined before and after acute ACTH stimulation every 6 months to investigate the maturation of adrenal steroidogenic enzyme activity. Serum dehydroepiandrosterone sulfate levels rose progressively throughout the study. An exponential model fit the longitudinal datasets well and indicated that dehydroepiandrosterone sulfate levels increased approximately 22%/yr from the youngest age onward. Increasing activity of 17-20 lyase (CYP17) and decreasing activity of 3beta-hydroxysteroid dehydrogenase were also evident in preadrenarchal subjects. When controlled for chronological age, no significant associations were noted between weight, body mass index, or body surface area and dehydroepiandrosterone sulfate levels. However, similar analyses revealed modest correlations of both height and growth velocity with dehydroepiandrosterone sulfate levels. Our results suggest that adrenarche is not the result of sudden rapid changes in adrenal enzyme activities or adrenal androgen concentrations; rather, adrenarche may be a gradual maturational process that begins in early childhood.

Polymorphism T-->C (-34 bp) of gene CYP17 promoter in Greek patients with polycystic ovary syndrome

OBJECTIVE

To investigate the frequency of T-->C substitution (-34 bp) of gene CYP17 promoter in Greek patients with polycystic ovary syndrome (PCOS) and to elucidate its role in the pathogenesis of the syndrome.

DESIGN

Follow-up study.

SETTING

Academic research setting.

PATIENT(S)

Fifty patients with PCOS and 50 healthy women.

INTERVENTION(S)

Body mass index and the waist-hip ratio were determined for each woman. Blood samples were obtained for DNA analysis and hormone estimates.

MAIN OUTCOME MEASURE(S)

Serum total T levels.

RESULT(S)

Seventeen patients (34%) did not carry the base pair substitution (genotype A1A1) and their mean (+/- SD) total T level was 75.7+/-32.2 ngl/dL, 29 patients (58%) were heterozygous carriers of the A2 allele (genotype A1A2) and their mean total T level was 77.8+/-29.9 ng/dL, and 4 patients (8%) carried the A2 allele in homozygosity (genotype A2A2) and their mean total T level was 87.0+/-2.8 ngl/dL. Twenty-two controls had the genotype A1A1 (44%) and their mean total T level was 39.1+/-15.5 ng/dL, whereas 28 (56%) had the genotype A1A2 and their mean total T level was 44.9+/-22.1 ng/dL. Homozygosity of the polymorphic A2 allele was not observed in controls, and this difference (8% versus 0%) was statistically significant.

CONCLUSION(S)

Although this base pair substitution is not the primary genetic defect in PCOS, it may aggravate the clinical picture of hyperandrogenemia, particularly when homozygosity exists.

Adrenocortical hyperresponsiveness to corticotropin in polycystic ovary syndrome patients with adrenal androgen excess

OBJECTIVE

To test the hypothesis that adrenal androgen (AA) excess in the polycystic ovary syndrome (PCOS) is due to a generalized exaggeration in AA output in response to adrenocorticotropic hormone (ACTH), and that this abnormality is due to an identifiable alteration in the biosynthesis of AAs.

DESIGN

Cross-sectional prospective controlled study.

SETTING

Academic tertiary care medical center.

PATIENT(S)

Patients with PCOS (n = 9) and without (n = 9) AA excess and controls (n = 12) without hyperandrogenism, matched for age and body mass.

INTERVENTION(S)

Acute 60-minute ACTH test was performed on patients.

MAIN OUTCOME MEASURE(S)

Basal levels of dehydroepiandrosterone sulfate (DHEAS), total testosterone (T), free T, and basal (Steroid(0)) and the 60-minute ACTH-stimulated levels (Steroid(60)) of pregnenolone (PREG), progesterone (P4), 17-hydroxypregnenolone (17-HPREG), 17-hydroxyprogesterone (17-HP), dehydroepiandrosterone (DHEA), and androstenedione (A4) were measured. Adrenocortical activities of 17-hydroxylase (17-OH), 17,20-lyase, and 3beta-hydroxysteroid dehydrogenase were estimated from product to precursor ratio, using Steroid(60) values.

RESULT(S)

Compared with PCOS patients without AA excess, PCOS patients with AA excess demonstrated significantly greater levels of DHEA(0) and A4(60). PCOS patients with AA excess had significantly higher activity of delta(5)17-OH, compared with PCOS patients without AA excess.

CONCLUSION(S)

Adrenal androgen excess in PCOS is associated with a greater delta(5)17-OH activity in response to ACTH.

Promising Tools in Prostate Cancer Research: Selective Non-Steroidal Cytochrome P450 17A1 Inhibitors

Cytochrome P450 17A1 (CYP17A1) is an important target in the treatment of prostate cancer because it produces androgens required for tumour growth. The FDA has approved only one CYP17A1 inhibitor, abiraterone, which contains a steroidal scaffold similar to the endogenous CYP17A1 substrates. Abiraterone is structurally similar to the substrates of other cytochrome P450 enzymes involved in steroidogenesis, and interference can pose a liability in terms of side effects. Using non-steroidal scaffolds is expected to enable the design of compounds that interact more selectively with CYP17A1. Therefore, we combined a structure-based virtual screening approach with density functional theory (DFT) calculations to suggest non-steroidal compounds selective for CYP17A1. In vitro assays demonstrated that two such compounds selectively inhibited CYP17A1 17α-hydroxylase and 17,20-lyase activities with IC50 values in the nanomolar range, without affinity for the major drug-metabolizing CYP2D6 and CYP3A4 enzymes and CYP21A2, with the latter result confirmed in human H295R cells.

A novel communication role for CYP17A1 in the progression of castration-resistant prostate cancer

BACKGROUND

CYP17A1 is currently a target for total androgen blockade in advanced prostate cancer (CaP) patients. After castration, or removal of testicular androgens, CYP17A1 can act as a rate-limiting enzyme in androgen synthesis from cholesterol or other adrenal precursors within the tumor microenvironment ultimately contributing to disease progression. Herein we provide evidence that CYP17A1 could also be a mediator of cell-to-cell communication within the CaP tumor microenvironment.

METHODS

CYP17A1 expression was evaluated by immunohistochemical analysis of human tumor sections and Western blot analysis of CaP patients' serum and exosome isolates. CYP17A1 activity assays were conducted in human serum (and positive control human liver and kidney microsomes) using progesterone as a precursor and an LC-MS endpoint.

RESULTS

These studies revealed that the expression pattern of CYP17A1 is typical of a secretory protein as it is localized to the luminal pole of the cells in exocrine secretory mode. CYP17A1 is expressed in human serum and in fact is elevated in the serum of CaP patients as compared to healthy controls. Serum CYP17A1 activity could not be confirmed, however, verification of CYP17A1 expression in exosomes suggests a role in cell-to-cell communication within the tumor microenvironment.

CONCLUSIONS

CYP17A1 is a crucial enzyme for de novo androgen synthesis within the tumor microenvironment after removal of testicular androgens by castration. We provide evidence for a novel role for CYP17A1 in serum and further reiterate the importance of targeting this enzyme in CaP progression.

Autoantibodies to human tryptophan hydroxylase and aromatic L-amino acid decarboxylase

OBJECTIVE

To assess the prevalence of autoantibodies (Abs) to tryptophan hydroxylase (TPH) and aromatic l-amino acid decarboxylase (AADC) in patients with different autoimmune diseases and to analyse their respective epitopes.

DESIGN

TPH and AADC Abs were measured in an immunoprecipitation assay using (35)S-labelled full-length and fragments of TPH and AADC.

METHODS

Patients with different autoimmune adrenal diseases (n=84), non-adrenal autoimmune diseases (n=37), idiopathic vitiligo (n=8) and 56 healthy blood donors were studied.

RESULTS

Fourteen of twenty-three (61%) of patients with autoimmune polyglandular syndrome (APS) type I and 1/34 (3%) of patients with isolated Addison's disease (AD) were positive for TPH Abs. None of the patients with APS type II (n=27), coeliac disease (n=10), autoimmune thyroid disease (AITD) (n=11), type 1 diabetes mellitus (DM) (n=16) or idiopathic vitiligo (n=8) was positive for TPH Abs. AADC Abs were detected in 12/23 (52%) patients with APS type I, in 1/29 (3%) patients with APS type II and 1/34 (3%) patients with isolated AD. None of the patients with coeliac disease, type 1 DM, AITD or idiopathic vitiligo was positive for AADC Abs. TPH Abs were found to interact with the C-terminal amino acids (aa) 308-423, central aa 164-205 and N-terminal aa 1-105 of the TPH molecule. AADC Ab binding epitopes were within the C-terminal aa 382-483, the central aa 243-381 and the N-terminal aa 1-167.

CONCLUSIONS

Our study suggests that TPH Abs and AADC Abs react with several different epitopes and that different epitopes are recognized by different sera. The prevalence of TPH Abs and AADC Abs in patients with APS type I in our study is in agreement with previous reports. TPH Abs and AADC Abs were found very rarely in patients with other forms of autoimmune adrenal disease and were not detected in patients with non-adrenal autoimmune diseases.

Ameliorative effects of fisetin in letrozole-induced rat model of polycystic ovary syndrome

BACKGROUND

The present study was conducted to investigate the therapeutic effects of a potent polyphenol, fisetin, on the letrozole-induced rat model of polycystic ovary syndrome (PCOS).

METHODOLOGY

Twenty-four female Wistar rats (42 days old) were divided into four groups: control group (received carboxy methylcellulose (CMC 0.5 %)), PCOS group treated with letrozole (1 mg/kg), fisetin group received same dose of letrozole + fisetin (10 mg/kg), and metformin group received same dose of letrozole + metformin (300 mg/kg). At the end of the experiment, biochemical (glucose, lipid profile) and hormonal (insulin, testosterone, estradiol, and progesterone) parameters were analyzed. Histological examinations of ovaries were also conducted by hematoxylin and eosin (H&E) staining. Real-time polymerase chain reaction (PCR) and western blotting were carried out for cytochrome P450 17A1 (CYP17A1), sirtuin-1 (SIRT1), and 5' AMP-activated protein kinase (AMPK) gene expression in the ovaries. Furthermore, enzymatic activities of antioxidants including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the ovaries were analyzed by colorimetric method.

RESULTS

Letrozole administration resulted in a remarkable abnormality in biochemical and hormonal parameters. Fisetin normalized levels of glucose, lipid profile, homeostatic model assessment for insulin resistance (HOMA-IR), testosterone, estradiol, and progesterone. Moreover, fisetin increased expression levels of SIRT1 and AMPK, and decreased expression level of CYP17A1 in the ovaries. Additionally, fisetin showed protective effect by enhancing antioxidant activities of CAT, SOD, and GPx depleted secondary to induction of PCOS. Fisetin effects were comparable to metformin, as the standard drug used for treatment of PCOS.

CONCLUSION

Our results showed that, fisetin treatment caused significant alleviating effects by restoring PCOS-induced alterations in the key genes involved in energy homeostasis and antioxidant enzymes, suggesting that it may have a key role in combating with PCOS.

Primary aldosteronism: functional histopathology and long-term follow-up after unilateral adrenalectomy

OBJECTIVES

To investigate the long-term outcome after unilateral adrenalectomy in patients with primary aldosteronism (PA) and to establish the role of functional pathology for the final diagnosis of aldosterone-producing adenoma (APA) or hyperplasia.

DESIGN

A single-centre, retrospective cohort study in a hospital setting.

PATIENTS

Consecutive patients with PA, n = 120, who underwent unilateral adrenalectomy between 1985 and 2010. Preoperative and postoperative data were analysed. To indicate the site of aldosterone secretion in the resected adrenal, we added functional methods to routine histopathology, using in situ hybridization and immunohistochemistry to detect the presence of enzymes needed for aldosterone (CYP11B2) and cortisol (CYP11B1, CYP17A1) synthesis.

RESULTS

The median follow-up was 5 years and the cure rate of PA 91%. Hypertension was improved in 97% and normalized in 38%. Functional histopathology changed the final diagnosis from APA to hyperplasia in 6 cases (7%). Five of these had no expression of or staining for aldosterone synthase in the adenoma, but only in nodules in the adjacent cortex. All except one APA patient were cured of PA. They had lower preoperative serum potassium and higher 24-h urinary aldosterone than patients with hyperplasia. Among patients with hyperplasia 16 of 26 were cured.

CONCLUSIONS

Most patients were cured of PA by unilateral adrenalectomy. Almost all noncured benefitted from the operation as the blood pressure improved. Functional histopathology proved helpful in the distinction between APA and hyperplasia, and we recommend that functional histopathology should be added to routine histopathology to improve the diagnostic evaluation and aid in tailoring the follow-up.

Testicular adrenal rests: evidence for luteinizing hormone receptors and for distinct types of testicular nodules differing for their autonomization

We report one patient with 21-hydroxylase deficiency and associated bilateral macro-orchidism caused by nodular hyperplasia of testicular adrenal rests (TAR). The boy, referred to us when 10 years old, was born with bilateral cryptorchidism that was treated unsuccessfully with i.m. injections of human chorionic gonadotropin (hCG) and later on with orchidopexy. He was treated with oral dexamethasone (0.625 mg per day) for the following 13 years. After one year, there was a marked reduction in steroid hormone levels (17-hydroxyprogesterone (17-OH P) from 27.2 to 1.2 nmol/l, testosterone from >104 to 4.8 nmol/l, estradiol (E(2)) from 481 to 33 pmol/l). After the same period of time, both testicular volume and nodularity decreased: from 45 to 18 ml and from numerous to four nodules in the right testis, and from 40 to 13 ml and from numerous to three nodules in the left testis. At the third year, there were transient increases in serum gonadotropins, testicular volume (right testis = 25 ml, left testis = 20 ml) and steroid hormones, including cortisol (serum ACTH and dehydroepiandrosterone sulfate remained suppressed). At the fourth year of follow-up, there were still four nodules in the right testis and three in the left testis. The LH-dependency (which implies possession of LH/hCG receptors) of these nodules was also substantiated by their steroidogenic response to an acute i.m. hCG test. An exogenous ACTH stimulation test increased serum 17-OH P and cortisol. Since these nodules, unlike the majority of those present initially, were not suppressed by the corticosteroid therapy and since they were not detected when the patient returned for control at 23 years of age, they had partial autonomy from ACTH. At 23 years of age, the patient had a single nodule in the right testis (right testis volume = 13 ml, left testis volume = 10 ml), which should have accounted for the consistent difference in size between the two gonads. Serum LH was about 7 mU/l and FSH about 23 mU/l. The responsiveness of plasma steroid hormones to hCG had changed quantitatively and qualitatively. Secretion of cortisol was absent, secretion of 17-OH P and testosterone was reduced, and secretion of E(2) was much increased. The ACTH stimulation test showed that serum cortisol did not respond, while the other steroids responded in the order of 17-OH P>E(2)> testosterone. We conclude that there were three different groups of TAR when the patient was already 10 years old: (i) ACTH-sensitive (the majority), (ii) partially ACTH-insensitive but LH/hCG-sensitive (three nodules in the left testis and three in the right testis), (iii) almost entirely ACTH-insensitive and partially hCG-insensitive (a single nodule in the right testis). Probably, the never suppressed gonadotropin levels (presumably due to the bilateral testicular damage subsequent to the cryptorchid state) and the hCG therapy were major etiological factors for the appearance of the second and third population of TAR.

CYP17 genotype predicts serum hormone levels among pre-menopausal women

BACKGROUND

CYP17, which encodes cytochrome P450c17alpha, mediates both steroid 17alpha-hydroxylase and 17,20-lyase activities, and is essential for the production of glucocorticoids and sex steroids. There is evidence that a common polymorphism in CYP17 (T27C) is associated with estrogen levels, making it a potential marker of disease risk.

METHODS

This is the first study to examine the relationship between CYP17 and estradiol (E2) using serum sampled exclusively from the early follicular phase of the menstrual cycle. We assessed the relationship between CYP17 and serum hormone levels, menstrual cycle length, bleed length, and age at menarche in 164 pre-menopausal women.

RESULTS

Among women with body mass index (BMI) < or =25 kg/m2, those with the TC and CC genotypes had 19 and 42% higher E2 (P for trend 0.007) and 14 and 30% higher dehydroepiandrosterone sulphate respectively (P for trend 0.10) than women with the TT genotype. Androstenedione levels did not differ between genotypes. Among women with BMI >25 kg/m2, hormone levels did not differ by genotype. Women with the C allele were also more likely to have menstrual cycle lengths <27 days [odds ratio (OR) for TC=2.36, 95% confidence interval (CI)=1.24-4.52; OR for CC=5.59, 95% CI=1.53-20.43 compared to TT]. CYP17 genotype was not associated with menstrual bleed length or age at menarche.

CONCLUSION

The CYP17 T27C polymorphism may be a marker of endocrine function.

Common classification schemes for PCB congeners and the gene expression of CYP17, CYP19, ESR1 and ESR2

BACKGROUND

Reliable techniques to measure polychlorinated biphenyl (PCB) congeners make the clearer definition of their effects on human health possible. Given that PCBs are classified as endocrine disrupters, we sought to explore the expression of some key genes involved in sex steroid metabolism.

OBJECTIVES

To examine common classification schemes of PCB congeners and determine whether exposure to groups classified by mechanism of action alter the gene expression (GE) of CYP17, CYP19, and ESR1 and ESR2.

METHODS

GE and exposure to various classifications of lipid-adjusted PCB congeners were examined in 139 daughters of the Michigan Fisheaters' Cohort. Using mixed models analyses and adjusting for age, menopausal status, and current use of oral contraceptives and hormone replacement therapy, GE data were regressed on exposure to PCB congener groupings based on mechanism of action.

RESULTS

Three novel findings are elucidated: first, that up-regulation of CYP19 expression is associated with exposure to PCB groupings containing dioxin-like, potentially anti-estrogenic, immunotoxic congeners, including PCB IUPAC #74, #105, #118, #138, #156, #157, #158, #167, and #170 from this cohort. Second, that exposure to similar congeners (PCB IUPAC #105, #156, #157, #158, and #167 in this cohort) but using a classification based solely on hormonal mechanisms of action is associated with increased expression of ESR2. Third, that increased expression of CYP17 is of borderline significance when associated with exposure to PCB IUPAC #118, #138, and #156.

CONCLUSIONS

These findings are both counter-intuitive and intriguing. Rather than exhibiting anti-estrogenic effects alone, they suggest that these congeners up-regulate the major enzyme involved in estrogen synthesis and tend to confirm previous findings of links between AhR and ER signaling pathways. Replication of these findings, expansion of the number of genes examined, exploration of mixtures of environmental chemicals, and subsequent study of health outcomes in a larger cohort are future priorities.

The steroid metabolome in lamotrigine-treated women with epilepsy

BACKGROUND

Epilepsy in women may be associated with reproductive disorders and alterations in serum steroid levels. Some steroids can be induced by epilepsy and/or treatment with antiepileptic drugs; however, there are still limited data available concerning this effect on the levels of other neuroactive steroid metabolites such as 3a-hydroxy-5a/b-reduced androstanes.

AIM

To evaluate steroid alterations in women with epilepsy (WWE) on lamotrigine monotherapy.

SUBJECTS AND METHODS

Eleven WWE and 11 age-matched healthy women underwent blood sampling in both phases of their menstrual cycles (MCs). The steroid metabolome, which included 30 unconjugated steroids, 17 steroid polar conjugates, gonadotropins, and sex hormone-binding globulin (SHBG), was measured using gas chromatography-mass spectrometry (GC-MS) and radioimmunoassay (RIA).

RESULTS

WWE had lower cortisol levels (status p<0.001), but elevated levels of unconjugated 17-hydroxypregnenolone (status p<0.001). Progesterone was higher in the follicular menstrual phase (FP) in WWE than in the controls (status×menstrual phase p<0.05, Bonferroni multiple comparisons p<0.05), whereas 17-hydroxyprogesterone was higher in WWE in both menstrual phases (status p<0.001). The steroid conjugates were mostly elevated in WWE. The levels of 5α/β-reduced androstanes in WWE that were significantly higher than the controls were etiocholanolone (status p<0.001), 5α-androstane-3α,17β-diol (status p<0.001), and the 5α/β-reduced androstane polar conjugates (status p<0.001).

CONCLUSIONS

WWE showed a trend toward higher circulating 3α-hydroxy-5α/β-reduced androstanes, increased activity of 17α-hydroxylase/17,20 lyase in the Δ(5)-steroid metabolic pathway, and increased levels of the steroid polar conjugates.

Lack of an ovarian function influence on the increased adrenal androgen secretion present in women with functional ovarian hyperandrogenism

OBJECTIVE

To evaluate whether ovarian function might have an influence on the adrenal hyperandrogenism present in patients with functional ovarian hyperandrogenism.

DESIGN

Controlled clinical study.

SETTING

Tertiary institutional hospital.

PATIENT(S)

Twenty-nine hirsute women with functional ovarian hyperandrogenism and 12 normal controls.

INTERVENTION(S)

The ACTH and GnRH tests were performed before and during triptorelin-induced ovarian suppression in patients. The normal women served as controls for the ACTH test.

MAIN OUTCOME MEASURE(S)

Basal and ACTH-stimulated steroid values.

RESULT(S)

All patients presented elevated T and free androgen index, which normalized after triptorelin. Patients with functional ovarian hyperandrogenism and adrenal hyperandrogenism, defined by elevated basal DHEAS (n = 10), presented enhanced delta 4-17, 20-lyase activity, which persisted during ovarian suppression. delta 4-17,20-lyase activity was normal in the functional ovarian hyperandrogenism patients without adrenal hyperandrogenism (n = 19). No correlation was observed between the any of the indexes of the adrenal enzymatic activities evaluated and plasma E2 or T.

CONCLUSION(S)

Increased adrenal delta 4-17,20-lyase activity is present in functional ovarian hyperandrogenism women with adrenal hyperandrogenism. No influence of the excess ovarian androgens or estrogens was found on any of the adrenal enzymatic pathways explored.

Low dose ketoconazole attenuates serum androgen levels in patients with polycystic ovary syndrome and inhibits ovarian steroidogenesis in vitro

OBJECTIVE

To investigate the effects of a low-dose ketoconazole on ovarian steroidogenesis and on serum androgen levels in polycystic ovary syndrome (PCOS).

DESIGN

In vitro, human granulosa-luteal cells were incubated with ketoconazole and radiolabeled steroid substrates, to follow their metabolic fate by thin-layer chromatography analysis. In vivo, normally cycling women (n = 7) in their luteal phase were administered one tablet of 200 mg ketoconazole at 8 A.M. Serum steroid levels, sampled basally and at 12 P.M., 4 P.M., and 8 A.M. the next morning, were compared with untreated control group (n = 7) values. Polycystic ovary syndrome women (n = 11) were similarly administered ketoconazole 6 to 10 days after occurrence of spontaneous menses. Adrenal origin of hyperandrogenemia was excluded by stimulation with ACTH and a normal basal DHEAS. The steroid diurnal variation was determined in the same patients a day before treatment.

RESULTS

In vitro, ketoconazole selectively inhibited the key steroidogenic cytochromes, namely P450scc, P45017 alpha, and P450arom (IC50 = 0.5 to 1.0 microgram/mL). In vivo, in the luteal phase, ketoconazole transiently decreased serum values (mean +/- SE) of E2 (19.2% +/- 2.1%) and P (38.3% +/- 8.5%) within 4 to 8 hours. The same low-dose ketoconazole, administered to PCOS women, decreased serum values of androstenedione (17.6% +/- 4.7%), T (24.6% +/- 7.6%), and free T (30.7% +/- 7.7%). In contrast, 17 alpha-hydroxyprogesterone increased concomitantly (78.5% +/- 10.8%), suggesting a greater suppressibility of the P45017 alpha lyase activity. The E2 levels in PCOS patients were slightly elevated (29.1% +/- 5.6%), resulting in a 1.7- to 2.3-fold increase of the E2:T ratio.

CONCLUSIONS

These findings suggest that a low-dose ketoconazole may facilitate a decreased intraovarian T:E2 ratio, which may prove favorable for follicular maturation in PCOS.

Abnormalities in the serum insulin-like growth factor-1 axis in women with hyperandrogenism

OBJECTIVE

To study the insulin-like growth factor-1 (IGF-1) axis in hirsute women.

DESIGN

Controlled clinical study.

SETTING

Tertiary care institutional hospital.

PATIENT(S)

Forty hirsute women and 17 women with normal menstrual cycles.

INTERVENTION(S)

Basal and ACTH-stimulated samples were obtained, and sampling was repeated 1 (gonadal stimulation) and 21 (gonadal suppression) days after a single 3.75-mg IM dose of triptorelin. Controls did not receive triptorelin for ethical reasons.

MAIN OUTCOME MEASURE(S)

Serum GH, IGF-1, IGF-binding protein-3 (IGFBP-3), insulin, glucose, total testosterone, sex hormone-binding globulin, E2, and gonadotropin levels. Basal and ACTH-stimulated steroid precursors were measured.

RESULT(S)

Patients with idiopathic hirsutism were identified by normal serum androgen levels (n=17). Those with functional ovarian hyperandrogenism (n=15) were identified by an increase in the serum testosterone level that normalized during gonadal suppression, whereas those with functional adrenal hyperandrogenism (n=8) were identified by an initial increase in the testosterone level that persisted during gonadal suppression. The adrenal hyperandrogenism group had increased IGF-1 levels compared with the control, idiopathic hirsutism, and ovarian hyperandrogenism groups. Patients with ovarian hyperandrogenism had normal TGF-1 concentrations, but their IGFBP-3 concentrations were lower than those of controls. No differences were observed in GH levels between any of the groups. These results persisted when the influence of age was corrected for.

CONCLUSION(S)

The IGF-1 axis appears to be involved in the pathogenesis of hyperandrogenism, especially in patients with adrenal hyperandrogenism, who have a clear increase in IGF-1 levels. Moreover, patients with ovarian hirsutism have decreased IGFBP-3 concentrations, which might enhance IGF-1 bioavailability.

Serum sex steroid hormone levels and polymorphisms of CYP17 and SRD5A2: implication for prostate cancer risk

Polymorphism of the steroid hormone-related genes might affect life-long androgen exposure, thus altering a risk of prostate cancer incidence. To evaluate the effect of the polymorphisms of CYP17 and SRD5A2 on serum steroid hormone levels, the 164 male Japanese cohort were tested for serum hormone levels and the genotype of the polymorphisms of CYP17 (T-C base substitution in the promoter region) and SRD5A2 (V89L). The linear trends across the CYP17 genotypes in serum-free testosterone and androstenedione levels were found, suggesting the importance of the polymorphism of CYP17 in determining the circulating androgen levels.

Indices of insulin sensitivity, beta cell function and serum proinsulin levels in the polycystic ovary syndrome

BACKGROUND

The study aim was to investigate the relationship between insulin resistance (IR), beta-cell function (betaF), hyperandrogenism and proinsulin levels during an oral glucose tolerance test (OGTT) in women with polycystic ovary syndrome (PCOS).

METHODS

One hundred and twenty-six selected women were classified as follows: PCOS, BMI > 25 kg/m2 (n = 39); PCOS, BMI < 25 kg/m2 (n = 54); controls, BMI > 25 kg/m2 (n = 14); controls, BMI < 25 kg/m2 (n = 19). Blood samples were collected between the third and sixth day of a spontaneous menstrual cycle, at 9:00 a.m., after an overnight fast. Serum levels of FSH, LH, PRL, 17alpha-OH-progesterone, SHBG, testosterone, delta4-androstenedione, insulin, proinsulin and glucose were measured. A 75 g OGTT was performed, and concentrations of glucose, insulin and proinsulin were also measured at t = 30, 60, 90, and 120 min.

RESULTS

The markers of insulin secretion and the AUC for proinsulin were higher in obese and overweight women and in women with PCOS, respectively. The AUC for proinsulin was positively correlated with markers of IR, betaF and androgen levels. An inverse relationship between PI/I values and indices of IR and betaF was observed.

CONCLUSIONS

Increased proinsulin levels reflect, most probably, insulin resistance, which is the key disorder in PCOS-associated metabolic abnormalities. Beta-cell function, pre-proinsulin mRNA processing and proinsulin conversion to insulin could be initially increased as a result of IR. An interaction between circulating proinsulin and androgen biosynthesis or action might also exist.

No association of the 5′ promoter region polymorphism of CYP17 gene with prostate cancer risk

CYP17 gene encodes the enzyme cytochrome p450c17alpha, which mediates two steps in the steroid biosynthesis pathway. Steroid hormones are believed to play a key role in the etiology of prostate cancer. A polymorphic T-->C transition in the 5(') promoter region of CYP17 creates an additional Sp1-type (CCACC box) promoter site (allele A2). We have evaluated the genotypic and allelic distribution of this polymorphism among 92 prostate cancer patients in order to assess risk by comparison with a population-based series of 200 healthy individuals from Brazil. Our results provide no evidence for an association between prostate cancer risk and CYP17 T/C polymorphism.

The effects of hexachlorobenzene on circulating levels of adrenal steroids in the ovariectomized rat

Hexachlorobenzene (HCB), is a global pollutant that resists degradation and possesses a propensity to bioaccumulate. However, the effect of HCB on adrenal function remains largely unknown. Thus, circulating levels of adrenal steroids in HCB-exposed (0.0, 1.0, 10.0, or 100.0 mg/kg/day--for 30 days by gavage) adult ovariectomized Sprague-Dawley rats (N = 32) were investigated. A terminal blood sample was collected for HCB residue analysis, and levels of circulating progesterone (P4), corticosterone (CS), and aldosterone (ALD) were quantified. Mean serum CS levels were significantly (P = 0.02) reduced by HCB exposure, starting with the lowest dose group (1.0 mg/kg/day for 30 days), whereas no differences in mean serum P4 and ALD levels were observed. Since it has been argued that the rodent possesses the ability to produce small amounts of cortisol and that levels of this glucocorticoid are altered in pathological states, serum cortisol (C) levels were also measured. Circulating levels of C were significantly lower (P < 0.05) in the highest dose group compared with controls. The presence of C in serum was confirmed by reverse-phase HPLC. These data suggest that even at the lowest dose studied, HCB exposure induces alterations in steroidogenesis of cells of the adrenal cortex inner zone.