Biological implications of estrogen and androgen effects on androgen receptor and its mRNA levels in human uterine endometrium

It has been shown that some effects of testosterone are different from those of its 5α-reduced metabolite, dihydrotestosterone. Briefly, activities of testosterone might be related to cellular differentiation, whereas dihydrotestosterone acts on cellular proliferation.

The number of testosterone binding sites in the uterine endometrium was increased by estradiol dipropionate, and this increase was down-regulated by testosterone cypionate. Dihydrotestosterone-specific binding sites in the endometrium were not modulated by estradiol dipropionate and testosterone cypionate. The dissociation constants of the bindings sites for testosterone and dihydrotestosterone were not altered by these steroids. Estradiol dipropionate with or without testosterone cypionate induced androgen receptor mRNA expression in the endometrium. In conclusion, testosterone might predominantly affect cellular differentiation in the endometrium.     

A novel androgen receptor gene mutation in a Chinese patient with complete androgen insensitivity syndrome

Objective

To identify the underlying androgen receptor gene mutation in a Chinese patient with typical symptoms of complete androgen insensitivity syndrome.

Study design

A Chinese female phenotype with 46, XY karyotype was diagnosed because of primary amenorrhea. Mutations were determined by polymerase chain reaction followed by DNA sequencing.

Results

DNA sequencing of the androgen receptor gene showed a G2439T transition causing E442X mutation in exon 1 in the patient with complete androgen insensitivity syndrome. The E442X mutation was a new de novo non-sense mutation in exon 1 of the androgen receptor gene. This non-sense mutation is located in the N-terminal transactivation domain and leads to a predicted truncated protein of 441 amino acids with loss of the end part of the N-terminal transactivation domain, and the DNA-binding and ligand-binding domain.

Conclusion

This E442X non-sense point mutation has not been described previously in cases of androgen insensitivity syndrome, and could lead to the synthesis of a short truncated non-functional androgen receptor probably responsible for the phenotype of complete androgen insensitivity syndrome in the affected individual. Gonadectomy should be planned to eliminate the risk of gonadal malignancy.     

A double nucleotide insertion-induced frame-shift mutation of the androgen receptor gene in a familial complete androgen insensitivity syndrome

Objective

A wide spectrum of androgen receptor (AR) gene mutations has been reported in complete androgen insensitivity syndrome (CAIS). The molecular basis of androgen resistance was investigated in a female with familial CAIS.

Study design

AR gene and protein were investigated by PCR and direct sequencing and Western immunoblotting, respectively.

Results

Sequencing analysis of DNA of the patient identified a double nucleotide insertion in exon 4 that results in the frame-shift leading to premature terminal signal in the beginning of exon 6. This mutation predicted the synthesis of a truncated AR that lacks the entire ligand-binding molecules. Immunoblotting analysis of the gonad removed from the patient detected the mutated AR protein of 94 kDa. Positive control revealed the normal apparent molecular mass of 110 kDa. DNA sequencing of her mother demonstrated the presence of both canonical and mutated sequences in the exon 4 through 8.

Conclusion

These findings suggested that the previously undescribed insertion mutation in the AR gene is the cause of CAIS in this family.     

Molecular analysis of the androgen receptor gene in 4 patients with complete androgen insensitivity

Androgen insensitivity syndromes are due to defects in the androgen receptor gene. In this study, we analyzed the androgen receptor gene in four cases with complete androgen insensitivity syndrome. In patient 1, one substitutional mutation [arginine (codon CGC) to cysteine (codon TGC) at position 774] of exon F was identified. This position was located in the hormone binding domain and appeared to be one hot spot of mutations because the mutations at the same position in several unrelated cases were reported before. In patient 2, one substitutional mutation [tyrosine (codon TAT) to cysteine (codon TGT) at position 571] of exon B was identified. This position was located in the DNA binding domain. In patients 3 and 4 (siblings), one substitutional mutation [arginine (codon CGA) to glutamine (codon CAA) at position 752] of exon E was identified. Taken together, these abnormalities might be related to the pathogenesis of complete androgen insensitivity. Received: 7 July 1997 / Accepted: 27 October 1997     

Vitamin D deficiency and androgen excess result eutrophic remodeling and reduced myogenic adaptation in small cerebral arterioles in female rats

Abstract

Vitamin D (vitD) insufficiency affects 1 billion people worldwide. Androgen excess (AE) occurs in 8% of fertile females. There are few data about the combined effect of vitD deficiency and AE on the early biomechanical changes of cerebral arterioles in fertile-aged female. Forty-six adolescent female Wistar rats (21–28?day-old, weighing 90–110?g) were grouped randomly in four groups: vitD supplemented groups with and without transdermal testosterone (T) treatment, as well as vitD deficient groups also with and without transdermal T (n?=?11 or 12, in all cases). After 8?weeks of treatment, anterior cerebral arterioles (in vivo diameter of 90–130 µm) were obtained and cylindrical segments were examined by pressure arteriography. Myogenic tone, tangential stress and incremental elastic moduli were computed and statistically analyzed. Elastic density was studied on resorcin-fuchsin-stained histological section. VitD deficiency with T treatment resulted in significantly lower inner radii and higher wall thickness values with reduced tangential stress and increased elastic fiber density. VitD deficiency reduced myogenic tone at higher intraluminar pressures (>110?mmHg). Our conclusion is that plasma vitD level is an important factor in the control of myogenic tone in cerebral resistance arteries. AE and vitD deficiency acting parallel induce remodeling of their wall.     

Identification of a mutant allele of the androgen receptor gene in a family with androgen insensitivity syndrome: detection of carriers and prenatal diagnosis

We report the results of a molecular study of a large family segregating the complete form of the Androgen Insensitivity Syndrome (CAIS) in several family members from three generations. We identified the mutant allele by polymerase chain reaction (PCR) amplification of the short tandem repeat (CAG)n, highly polymorphic in the population, present in the first exon of the androgen receptor (AR) gene. In this family four different alleles were detected and one of these showed a perfect segregation with the disease.This study enabled us to identify the heterozygous females in this family. We think that this simple, indirect test, is also suitable for prenatal diagnosis of Morris' syndrome when the mother is heterozygous for the size of the short tandem repeat and one affected subject in the family may be studied.     

Androgen receptors,serum androgen levels and survival of breast cancer patients

Summary Steroid receptor levels and serum androgen levels were determined in 61 breast cancer patients and 34 patients with non-malignant breast lesions. Testosterone and dehydroepiandrosterone-sulfate did not and androstenedione did show a difference between the two groups. Androgen levels had no influence on survival rates. Androgen receptor (AR) levels correlated with progesterone receptor levels, but not with estrogen receptor levels or with tumor stage. Patients with positive AR findings had a better survival rate; this was independent of tumor stage. AR findings may therefore be a prognostic index in breast cancer patients.     

Relationships between maternal novel adipocytokines and bone biomarkers in complicated by gestational hypertensive disorders and normal pregnancies

Abstract

Objective: To investigate possible associations of the novel adipocytokines resistin, apelin and visfatin (implicated in the complex control of bone biology) with several biochemical determinants of bone turnover in maternal blood from normal pregnancies and pregnancies complicated by gestational hypertensive disorders (preeclampsia or pregnancy-induced hypertension).

Methods: Circulating maternal concentrations of resistin, apelin and visfatin were correlated with circulating markers of bone formation [osteocalcin (OC), bone-specific alkaline phosphatase (BALP)] and resorption [osteoprotegerin (OPG), soluble receptor activator of nuclear factor-κB ligand (sRANKL) and cross-linked N-telopeptide of type I collagen (NTx)] in full-term pregnancies (20 normal and 20 complicated by gestational hypertensive disorders).

Results: In normal pregnancies, no correlation was recorded between maternal concentrations of adipocytokines and the above bone biomarkers. In pregnancies with gestational hypertensive disorders, maternal apelin concentrations negatively correlated with NTx ones (r?=??0.489, p?=?0.034), while maternal visfatin concentrations positively correlated with OPG ones (r?=?0.464, p?=?0.039).

Conclusions: No associations were found between maternal concentrations of all three studied adipocytokines and respective concentrations of bone biomarkers in normal pregnancies. By contrast, in pregnancies with gestational hypertensive disorders, maternal concentrations of apelin and visfatin correlated with respective concentrations of indices of bone turnover. Further prospective studies are needed to clarify these relationships.     

Effects of ACE inhibition and beta-blockade on female genital structures in spontaneously hypertensive rats

Introduction and AimThis study evaluated the possible differences between an angiotensin converting enzyme (ACE) inhibitor and a beta-blocker concerning their potential protective role on female external genitalia in spontaneously hypertensive rats (SHR).Main Outcome MeasuresMorphological changes in the clitoris after antihypertensive treatments.MethodsFor 6 months, SHR received no treatment; SHR + ramipril (RAM), SHR + atenolol (AT), and control Wistar Kyoto (WKY) rats received no treatment. Clitorises were processed for immunohistochemistry using anti-α-smooth muscle actin (α-SMA), anti-collagen I and III, anti-transforming growth factor β₁ (TGFβ₁), and anti-endothelial nitric oxide synthase (eNOS) antibodies.ResultsSHR + RAM and SHR + AT presented significantly lower blood pressure in both groups vs. untreated SHR. Compared with WKY, α-SMA was increased in the arteries and in the cavernous spaces of the clitoris together with a marked increase in wall/lumen ratio in clitoral vessels in untreated SHR. All these alterations were diminished in SHR + AT (P < 0.01). SHR + RAM presented differences with respect to SHR + AT in the reduction of these variables. TGFβ₁ expression in the vessel wall from the clitoris and collagen I and III deposition in the interstitium from the clitoris in untreated SHR were significantly more (P < 0.01) than in WKY. While SHR + AT showed a mild decrease in these variables, SHR + RAM presented a significant reduction (P < 0.01) in TGFβ₁ expression interstitial fibrosis and in both types of collagens. Positive immunostaining of eNOS in the sinusoidal endothelium from the clitoris was less (P < 0.01) in untreated SHR (3.4 ± 1.3%) and SHR + AT (5.1 ± 1.2%) than in SHR + RAM (17.2 ± 1.6%) and WKY (15.9 ± 1.7%). Untreated SHR and SHR + AT presented more surrounding connective tissue at the perineurium in the clitoris (P < 0.01) than SHR + RAM.ConclusionACE inhibition provided a considerable protective role on the female external genitalia structures in SHR by a mechanism that may be, at least in part, independent of the degree of blood pressure lowering. Toblli JE, Cao G, Casabé AR, and Bechara AJ. Effects of ACE inhibition and beta-blockade on female genital structures in spontaneously hypertensive rats.     

Estrogen secretion from a malignant sex cord stromal tumor in a patient with complete androgen insensitivity

We report on a 68-year-old patient with complete androgen insensitivity syndrome (testicular feminization syndrome) in whom an estrogen-secreting malignant sex cord stromal tumor developed in an intraabdominal testis. We believe this to be the first such case to document estrogen secretion by the tumor.(Am J Obstet Gynecol 1997;177:1541-2.)     

The association between androgen receptor gene CAG polymorphism and polycystic ovary syndrome: a case-control study and meta-analysis

Purpose

Many studies have been carried out to confirm the relationship between androgen receptor gene CAG repeat polymorphism and polycystic ovary syndrome (PCOS), without consistent results. Hence we conducted the current study to research this relationship.

Methods

224 Chinese Han women with PCOS and 223 in vitro fertilization and embryo transplantation (IVF-ET) infertile women with tubal factor or male infertility served as the controls were recruited in our study. PCR-based assays were applied to genotype the (CAG)_n repeat alleles. A meta-analysis including 1,536 PCOS patients and 1,807 controls was conducted to produce a pooled estimate.

Results

We observed that the CAG bi-allelic mean lengths were similar in PCOS patients and controls (22.65 ± 2.5 vs. 23.09 ± 2.1, P = 0.116). When CAG bi-allelic were divided into two categories (mean repeats ≤22, >22), the short AR-CAG bi-allelic showed more frequent in PCOS group than in controls (56.25 % vs 29.14 %, P < 0.001). Further analysis presented that, in PCOS, there was a lower mean CAG repeat lengths in mean bi-allelic lengths (22.3 ± 2.5 vs. 23.9 ± 2.2, P = 0.008) and long bi-allelic lengths (24.3 ± 1.4 vs. 25.9 ± 1.6, P = 0.05) among patients with testosterone less than 0.7 ng/ml compared with those whose testosterone was more than 0.7 ng/ml. Besides, the testosterone were positively correlated with the CAG polymorphism (r = 0.237, P = 0.008), which accorded with our meta-analysis results.

Conclusions

The distribution of AR-CAG allele differed between PCOS patients and controls, and polymorphism of CAG repeat lengths may contribute to hyperandrogenism in PCOS.     

Androgen receptor gene mutation identified by PCR-SSCP and sequencing in 4 patients with complete androgen insensitivity syndrome

To study the genetic defect of the human androgen receptor (hAR) gene in the complete androgen insensitivity syndrome (CAIS), we amplified each of the eight exons by PCR in genomic DNA extracted from the paraffin blocks of the resected gonads. We analyzed using SSCP, and directly sequenced the abnormally shifted bands. Mutations were found in 4 cases of CAIS. Patient 1 carried a point mutation; a G to A transition in exon 7 resulted in a change from arginine to glutamine at codon 831. Patient 2 carried a point mutation; a C to T transition in exon 7 resulted in a change from arginine to stop at codon 831. Patient 3 carried a point mutation and deletion in exon 7. A point mutation was an A to G transition that caused a glutamine to be substituted for the asparagine present at codon 819. A deletion of a G at codon 820 resulted in a frameshift and consequently in the introduction of a premature stop at codon 821. Patient 4 carried a mutation in 5’ splice donor site of intron 7; a G to T transition might have caused an abnormal splicing of the exon 7. All of the mutations were found in exon 7. These mutations of hAR gene might be related to the pathogenesis of CAIS. Received: May 1999 / Accepted: 17 August 1999     

Molecular analysis of the androgen receptor gene in Hong Kong Chinese infertile men

Purpose : To investigate the relationship between CAG repeat length in the androgen receptor gene and impaired spermatogenesis in Hong Kong Chinese population. Methods : The CAG repeat region was amplified by polymerase chain reaction (PCR) in 85 nonobstructive azoospermic or severe oligozoospermic men, and 45 fertile males. The number of CAG repeat was analyzed by DNA sequencing. Serum FSH, LH, and testosterone levels were also determined in these men. Results : Among nonobstructive azoospermic males, three men (5.7%) possessed short CAG repeats (<16), and three (5.7%) other men possessed long CAG repeats (>30). Short CAG repeats (<16) were also found in two severe oligozoospermic males (6.3%). The incidence of infertile men with short or long CAG repeats is significantly higher in the azoospermic group (p = 0.03) but not in the severe oligozoospermic group (p = 0.17) when compared with the fertile controls. Conclusion : Our data suggest an association between CAG repeat lengths and impaired spermatogenesis in azoospermic males in our population.     

Effects of estradiol alone and combined with norethisterone acetate on pulse-wave velocity in hypertensive postmenopausal women

Background.?Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries.

Objectives.?To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate.

Subjects.?Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III).

Methods.?Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior® device, taken at baseline and after 12 weeks of treatment.

Results.?After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively).

Conclusions. PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.     

Androgen receptor expression is a biological marker for androgen sensitivity in high grade serous epithelial ovarian cancer

Objectives

In the present study we explore the effects of androgens and anti-androgens on primary cultures of EOC cells. We also investigate the effects of chemotherapy on AR expression. Epithelial ovarian cancer (EOC) arises from ovarian surface epithelial cells (OSE), which express the androgen receptor (AR). Androgen stimulation of OSE cells results in increased proliferation and protection from apoptosis. Nevertheless, in clinical trials anti-androgens have had a low objective response rate in relapsed ovarian cancer.

Methods

1. Androgen receptor (AR) expression and response to androgenic stimulation were correlated in primary ovarian cancer cells derived from ascitic fluid from patients with advanced ovarian cancer,2. AR expression in primary epithelial ovarian cancer was investigated before and after chemotherapy using paired histological samples which had been incorporated into a tissue microarray.

Results

Eleven primary ovarian cancer cultures were established from ascitic fluid. There was wide variation of expression of androgen receptor mRNA between cultures. Cell division increased after dihydro-testosterone (DHT) stimulation in 6 out of 11 primary cultures. The fraction of cells in S-phase increased from 4.4% in cells grown in serum-free medium to 8.3% in cells stimulated with 100 nM of DHT (P < 0.001). The increase in S-phase fraction was abrogated after treatment with the anti-androgen, bicalutamide in 4 out of 5 responsive cultures. There was a strong correlation (r² = 0.7) between nuclear AR expression by immunohistochemistry and S-phase fraction changes in primary cultures.Paired pre- and post-chemotherapy histological samples from 29 patients were incorporated into a tissue microarray (TMA). Nuclear and cytoplasmic AR expression by immunohistochemistry (IHC) decreased significantly after chemotherapy (P < 0.01).

Conclusion

AR expression correlates with increased S-phase fraction in response to androgenic stimulation. Immunohistochemical analysis of AR expression needs to be further tested in clinical trials to select AR positive EOC for anti-androgen therapy. Anti-androgen use early in the course of ovarian cancer is more likely to be effective as these data suggest that androgen receptor expression decreases with exposure to chemotherapy and this may explain the low response rates seen in clinical trials of patients heavily pre-treated with multiple courses of chemotherapy.     

P-wave and QT dispersion in hypertensive disorders of pregnancy

Abstract

Aim: To compare P-wave and QT dispersion values in hypertensive disorders of pregnancy and controls and also in preeclampsia, chronic hypertension, and gestational hypertension separately.

Material and methods: We included 140 hypertensive pregnants and 110 healthy age-matched pregnants in this study. The hypertensive pregnants were divided into three subgroups: preeclampsia (n?=?43), chronic hypertension (n?=?51), and gestational hypertension (n?=?46). P-wave and QT dispersion values were compared between groups.

Results: Hypertensive pregnants had higher P-wave (41.74?±?5.51 vs. 37.73?±?5.62, p?<?.001) and QTc dispersion (45.44?±?7.62 vs. 39.77?±?8.34, p?<?.001) values. In subgroup analysis, P-wave dispersion and QTc dispersion were different between preeclamptic, chronic hypertensive, and gestational hypertensive patients. Also, they were significantly higher in chronic hypertension as compared to gestational hypertension and they were higher in preeclampsia than in gestational hypertension. No difference was found according to these parameters between preeclampsia and chronic hypertension. In correlation analysis, both P-wave dispersion and QTc dispersion were positively correlated with systolic (r?=?0.409, p?<?.001 and r?=?0.306, p?<?.001) and diastolic blood pressure (r?=?0.390, p?<?.001 and r?=?0.287, p?<?.001) which are main clinical determinants of hypertensive disorders.

Conclusion: In clinical practice, chronic hypertensive pregnants are generally followed up in their future life for cardiovascular disorders. Also, we recommend that we must inform and follow preeclamptic patients for future cardiovascular diseases.