Aromatase deficiency in an Ontario Old Order Mennonite family.

OBJECTIVES: Aromatase deficiency is a rare autosomal recessive disease that results in the absence of aromatase. In females it presents with ambiguous genitalia and lack of secondary sexual characteristics during puberty. Aromatase deficiency is not attributed to any specific population, but it is more commonly seen in consanguineous parents. Herein, we report the first Old Order Mennonite family with that diagnosis. CASE PRESENTATION: Our proband is an Old Order Mennonite female born with ambiguous genitalia who was identified to carry novel homozygous variant in the CYP19A1 gene c.1304G>A (p. Arg435His). Her older brother was later confirmed with the same genetic diagnosis. CONCLUSIONS: Recognizing the cultural sensitivity, unrecognized affected cases, and late presentation of males affected with aromatase deficiency, this condition may be more prevalent than believed in that population.

A novel nonsense mutation in HSD17B3 gene in a Tunisian patient with sexual ambiguity.

INTRODUCTION: 17ß-hydroxysteroid dehydrogenase type 3 (HSD17B3) isoenzyme is present almost exclusively in the testes and converts delta 4 androstenedione to testosterone. Mutations in the HSD17B3 gene cause HSD17B3 deficiency and result in 46,XY Disorders of Sex Development (46,XY DSD). AIM: This study aimed to present the clinical and biochemical features of a Tunisian patient who presented a sexual ambiguity orienting to HSD17B3 deficiency and to search for a mutation in the HSD17B3 gene by DNA sequencing. METHODS: Polymerase chain reaction (PCR) amplification and subsequent sequencing of all the coding exons of HSD17B3 gene were performed on genomic DNA from the patient, her family, and 50 controls. RESULTS: Genetic mutation analysis of the HSD17B3 gene revealed the presence of a novel homozygous nonsense mutation in the exon 9 (c.618 C>A) leading to the substitution p.C206X. The mutation p.C206X in the coding exons supports the hypothesis of HSD17B3 deficiency in our patient. CONCLUSION: The patient described in this study represented a new case of a rare form of 46,XY DSD, associated to a novel gene mutation of HSD17B3 gene. The screening of this mutation is useful for confirming the diagnosis of HSD17B3 deficiency and for prenatal diagnosis.

Significance of phosphatase and tensin homologue (PTEN), O(6)-methylguanine-DNA methyltransferase (MGMT), and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) protein expression in gynaecomastia.

This study was designed to investigate the pathogenesis of gynaecomastia by measuring phosphatase and tensin homologue (PTEN), O(6)-methylguanine-DNA methyltransferase (MGMT) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) protein in breast tissue specimens from 68 patients with gynaecomastia and 24 normal male controls using immunohistochemical staining. The gynaecomastia cases were divided into three different histological types: florid, intermediate and fibrous. The PTEN, MGMT and DNA-PKcs proteins were detected in both gynaecomastia and normal breast tissue, but the levels of immunohistochemical staining of each protein were significantly lower in gynaecomastia breast tissue than in normal breast tissue. There were also significant differences in the levels of immunohistochemical staining for the three proteins according to gynaecomastia histological type. These results suggest that abnormally low levels of PTEN, MGMT and DNA-PKcs protein in gynaecomastia breast tissue may play a role in the development of gynaecomastia. Further research is required to elucidate fully their individual roles in the pathophysiology of gynaecomastia.

Non-classical 21-hydroxylase deficiency in boys with prepubertal or pubertal gynecomastia.

This report describes two boys who were evaluated for the first time at the ages of 9.8 (patient 1) and 13.4 years (patient 2), due to either prepubertal or pubertal gynecomastia. The diagnosis of non-classical (NC) 21-hydroxylase deficiency (21-OH-D) was substantiated by the finding of increased baseline and adrenocorticotropic hormone (ACTH)-stimulated 17-hydroxy-progesterone levels and was supported by molecular analyses of the CYP21A2 gene, which revealed V281L homozygosis in patient 1 and V281L/P30L compound heterozygosis in patient 2. In both boys, gynecomastia completely regressed 5-8 months after the institution of glucocorticoid substitutive treatment. We conclude that it is mandatory to suspect NC 21-OH-D in the clinical evaluation of either prepubertal or pubertal gynecomastia, since this association might be more frequent than reported so far, and that it is important that diagnosis is made by the first months after gynecomastia development, since a longstanding gynecomastia is unlikely to respond completely to medical therapy.

Possible involvement of aromatase overexpression induced by cyclo-oxygenase-2 in the pathogenesis of idiopathic gynecomastia.

The pathogenesis of idiopathic gynecomastia, which shows no imbalance in serum estrogens and androgens levels unlike gynecomastia of other causes, is unknown. It seems to be of interest to study the in situ aromatase expression in idiopathic gynecomastia to investigate a possible involvement of intratumoral biosynthesis of estrogens in the pathogenesis of this disease. The expression level of aromatase mRNA was studied by a real-time polymerase chain reaction (PCR) assay in four idiopathic gynecomastia cases (two florid type and two fibrous type). In addition, the proportion of promoter usage (promoters I.3 I.4, l. 7, and PII) of the aromatase gene was determined by PCR-gel electrophoresis. Localization of aromatase and cyclo-oxygenase-2 (COX-2) expression was studied by immunohistochemistry. The aromatase mRNA level of the florid type gynecomastia (3.05 and 1.66) was higher than that in the fibrous type (0.76 and 0.04). The proportion of promoter Pll in the florid type (94.1% and 84.8%) was very high as compared with that of the fibrous type (0.7% and 0.5%). Immunohistochemical studies have revealed that aromatase and COX-2 were strongly expressed in the duct epithelial cells in the florid type, but they were weak or negative in the fibrous type. COX-2 is suggested to upregulate aromatase expression by enhancing the transcription via promoter Pll in idiopathic gynecomastia of the florid type but not of the fibrous type. Because idiopathic gynecomastia initially develops as the florid type and regresses as the fibrous type, a high estrogen milieu induced by increased aromatase expression is speculated to play some role in the pathogenesis of idiopathic gynecomastia.

Estrogen excess associated with novel gain-of-function mutations affecting the aromatase gene.

BACKGROUND: Gynecomastia of prepubertal onset may result from increased estrogen owing to excessive aromatase activity in extraglandular tissues. A gene in chromosome 15q21.2 encodes aromatase, the key enzyme for estrogen biosynthesis. Several physiologic tissue-specific promoters regulate the expression of aromatase, giving rise to messenger RNA (mRNA) species with an identical coding region but tissue-specific 5'-untranslated regions in placenta, gonads, brain, fat, and skin. METHODS: We studied skin, fat, and blood samples from a 36-year-old man, his 7-year-old son, and an unrelated 17-year-old boy with severe gynecomastia of prepubertal onset and hypogonadotropic hypogonadism caused by elevated estrogen levels. RESULTS: Aromatase activity and mRNA levels in fat and skin and whole-body aromatization of androstenedione were severely elevated. Treatment with an aromatase inhibitor decreased serum estrogen levels and normalized gonadotropin and testosterone levels. The 5'-untranslated regions of aromatase mRNA contained the same sequence (FLJ) in the father and son and another sequence (TMOD3) in the unrelated boy; neither sequence was found in control subjects. These 5'-untranslated regions normally make up the first exons of two ubiquitously expressed genes clustered in chromosome 15q21.2-3 in the following order (from telomere to centromere): FLJ, TMOD3, and aromatase. The aromatase gene is normally transcribed in the direction opposite to that of TMOD3 and FLJ. Two distinct heterozygous inversions reversed the direction of the TMOD3 or FLJ promoter in the patients. CONCLUSIONS: Heterozygous inversions in chromosome 15q21.2-3, which caused the coding region of the aromatase gene to lie adjacent to constitutively active cryptic promoters that normally transcribe other genes, resulted in severe estrogen excess owing to the overexpression of aromatase in many tissues.

Aromatase expression in the human male.

The role of estrogens produced by the testis may involve negative feedback regulation of androgen biosynthesis. Estrogens are also associated with contractile processes of seminiferous tubules, and might have mitogenic effects on Sertoli and Leydig cells. To investigate the location of aromatase (estrogen synthetase) in the testes, tissue from normal human subjects, aged 3 months to 72 years were studied using immunocytochemistry. In mature testes, aromatase immunostain was always associated with Leydig cells and was absent from Sertoli cells. Aromatase activity ranged from 0.014-0.55 pmol estrogen per mg/h and was significantly correlated with the immunostain intensity (P<0.02). Activity and immunostain intensity did not correlate with increasing age. Rather, the highest levels were measured in four of six testes of men aged 18-20 years, three of whom also had the strongest immunostain in larger and more prominent Leydig cell clusters than those in the other specimens. A low level of aromatase activity but no immunostain was detected in prepubertal testes. However, in several prepubertal patients with Peutz-Jegher's Syndrome (PJS) with bilateral multifocal sex cord tumors and enlarged seminiferous tubules and Sertoli cells, aromatase was expressed in these Sertoli cells, but absent from normal Sertoli and Leydig cells. Increased aromatase expression in these tissues involved activation of upstream regulatory elements of the gonadal P II promoter of P-450(arom). In a prepubertal boy with gynecomastia but without PJS, aromatase excess appeared to be due to increased aromatization in skin fibroblasts and lymphocytes. Several members of the patient's family including his sister also expressed high levels of aromatase. This condition appears to be inherited in an autosomal dominant manner.

Overexpression of aromatase in transgenic male mice results in the induction of gynecomastia and other biochemical changes in mammary glands.

Our previous studies have shown that overexpression of aromatase in mammary glands results in the induction of hyperplastic and dysplastic changes in female transgenic mice. In this study we show that overexpression of aromatase in male transgenic mice results in increased mammary growth and histopathological changes similar to gynecomastia. Increased estrogenic activity also results in an increase in estrogen and progesterone receptor expression in the mammary glands of transgenic males as compared to the nontransgenic males, as well as an increase in the expression of various genes involved in cell cycle and cell proliferation. We have also observed an increase in certain growth factors, such as bFGF and TGFbeta, as a result of aromatase overexpression in the male transgenic mammary glands. In order to obtain a better understanding of the biological significance of gynecomastia, a reliable model is necessary to explain the mechanisms and correlations associated with human cancers. This model, can potentially serve as a predictable and useful tool for studying gynecomastia, hormonal carcinogenesis and action of other carcinogens on hormone induced cancers.

Expression of pepsinogen C in gynecomastias and male breast carcinomas.

Pepsinogen C is a proteolytic enzyme involved in the digestion of proteins in the stomach; it is also synthesized by a significant percentage of female breast carcinomas. In addition, it has been demonstrated that pepsinogen C is one of the few proteins induced by androgens in breast carcinoma cells. Here we evaluate the expression of pepsinogen C by immunoperoxidase staining in normal breast tissue from 3 male patients, 15 gynecomastia tissues, 2 male in situ breast carcinomas, and 68 male invasive breast carcinomas. Pepsinogen C immunostaining values were quantified in male breast tumors using the HSCORE system, which considers both the intensity and the percentage of cells staining at each intensity. The results indicated positive immunohistochemical staining for pepsinogen C in all gynecomastia tissues, the two in situ ductal carcinomas, and 52 of 68 invasive breast carcinomas (76.4%). The three normal breast tissues analyzed showed negative staining for pepsinogen C, whereas invasive tumors showed clear differences among them with regard to the intensity and percentage of staining cells. In addition, pepsinogen C scores were significantly higher in well-differentiated (grade I, 188.7) and moderately differentiated (grade II, 145.8) tumors than in poorly differentiated (grade III, 98.5) tumors (p = 0. 032). Similarly, significant differences in pepsinogen C content were found between estrogen receptor (ER)-positive tumors and ER-negative tumors (158.5 vs. 44.3, respectively; p = 0.009). Patients with pepsinogen C-positive tumors reached longer relapse-free and overall survival periods than did those with tumors with negative staining, but no statistical differences were observed between survival curves calculated for these two groups of patients. This results demonstrate expression of pepsinogen C by gynecomastias and by a high percentage of male breast carcinomas and may indicate an important role of pepsinogen C in the pathophysiology of male breast diseases.

Aromatase and gynecomastia.

An imbalance between estrogen action relative to androgen action at the breast tissue level results in gynecomastia. Enhancement of aromatization of androgens to estrogens is important in the pathogenesis of gynecomastia associated with obesity, aging, puberty, liver disease, thyrotoxicosis, 17-oxosteroid reductase deficiency. Klinefelter's syndrome, and neoplasms of the testes, adrenals and liver. A primary aromatase excess syndrome with exuberant gynecomastia had been found both sporadically and in a familial setting. Although aromatase inhibition would appear to be an important class of drugs to treat gynecomastia, relatively little published data with these drugs exist and most concern the use of delta1-testolactone, which reduces the size of the breast glandular tissue, but does not completely ameliorate the problem. Studies with the newer generation of more potent aromatase inhibitors need to be carried out.

Molecular basis of severe gynecomastia associated with aromatase expression in a fibrolamellar hepatocellular carcinoma.

This report represents the first study in the literature linking development of severe gynecomastia, in a 17 1/2-yr-old boy, to high levels of aromatase expression in a large fibrolamellar hepatocellular carcinoma, which gave rise to extremely elevated serum levels of estrone (1200 pg/mL) and estradiol-17 beta (312 pg/mL) that suppressed FSH and LH (1.3 and 2.8 IU/L, respectively), and consequently testosterone (1.53 ng/mL). After removal of a 1.5-kg hepatocellular carcinoma, gynecomastia partially regressed, and essentially, normal hormone levels were restored (estradiol-17 beta, < 50 pg/mL; estrone, 74 pg/mL; testosterone, 6.85 ng/mL; and FSH/LH, 6.3/3.7 mIU/mL). Conversion of C19 steroids to estrogens occurs in a number of human tissues and is catalyzed by aromatase P450 (P450arom), the product of the CYP19 gene in a number of human tissues. Tissue-specific promoters are used to regulate P450arom gene transcription in adult human tissues, e.g. promoters I.4 and I.3 in adipose fibroblasts, and promoter II in the gonads. Human fetal liver uses promoter I.4 to express markedly high levels of P450arom, whereas hepatic P450arom expression normally becomes undetectable in postnatal life. Using immunohistochemistry, diffuse intracytoplasmic aromatase expression was detected in the liver cancer cells from this severely feminized boy. Northern analysis indicated the presence of P450arom transcripts in total RNA from the hepatocellular cancer but not in the adjacent liver nor in disease-free adult liver samples. Promoter use for aromatase expression was determined by a specific RT-PCR method. Promoters I.3 and II were used for P450arom gene expression in the hepatocellular cancer tissue. Because aromatase is not expressed in the disease-free adult liver, the presence of extremely high levels of aromatase expression in this fibrolamellar hepatocellular carcinoma tissue is intriguing, particularly because there is preferential use of the proximally located P450arom promoters I.3 and II by the tumor, instead of the much more distally located fetal liver-type promoter I.4.

Male hypogonadism with gynecomastia caused by late-onset deficiency of testicular 17-ketosteroid reductase.

BACKGROUND: 17-Ketosteroid reductase deficiency results in male pseudohermaphroditism because conversion of the weak androgen androstenedione to the more potent androgen testosterone is impaired. If a late-onset form exists, hypogonadism and gynecomastia caused by decreased testosterone production and increased estrogen production, respectively, would be expected as the major clinical manifestations in men. METHODS: We studied 48 male subjects, ranging from 14 to 26 years of age, who had idiopathic pubertal gynecomastia. Serum concentrations of gonadal and adrenal steroid hormones were measured before and after the administration of corticotropin and after the combined administration of chorionic gonadotropin and dexamethasone for three days. RESULTS: We identified three unrelated subjects (ages, 16, 17, and 26 years) with results indicative of a partial deficiency of testicular 17-ketosteroid reductase. The three subjects had gynecomastia as well as decreased libido and impotence. Their mean (+/- SD) base-line serum androstenedione and estrone concentrations were elevated as compared with the levels in the 45 subjects without this enzyme deficiency (androstenedione, 380 +/- 70 vs. 110 +/- 70 ng per deciliter [13 +/- 2 vs. 4 +/- 2 nmol per liter]; estrone, 138 +/- 12 vs. 46 +/- 9 pg per milliliter [511 +/- 44 vs. 170 +/- 33 pmol per liter]). After the administration of chorionic gonadotropin, the mean serum androstenedione concentration in these three subjects was 910 +/- 48 ng per deciliter (32 +/- 2 nmol per liter) and the mean serum estrone concentration was 260 +/- 16 pg per milliliter (962 +/- 59 pmol per liter). The mean serum testosterone concentration at base line was 210 +/- 80 ng per deciliter (7.4 +/- 2.8 nmol per liter) in the 3 subjects, as compared with a value of 410 +/- 12 ng per deciliter (14.4 +/- 0.42 nmol per liter) in the 45 other subjects, and it did not increase in response to the administration of chorionic gonadotropin. The concentrations of androstenedione and estrone in spermatic venous serum were 19 times higher and 73 times higher, respectively, than in normal men. The serum concentrations of follicle-stimulating hormone and luteinizing hormone in these three subjects were inappropriately low, suggesting the presence of hypogonadotropic hypogonadism. CONCLUSIONS: A late-onset form of testicular 17-ketosteroid reductase deficiency can cause gynecomastia and hypogonadism in men.

[Clinical features and diagnosis of mild 3-beta-hydroxysteroid dehydrogenase deficiency in men]. / Klinik und Diagnostik bei Männern mit leichtem 3 beta-Hydroxysteroiddehydrogenase-Mangel.

3 beta-hydroxysteroid dehydrogenase (HSD) deficiency was demonstrated in six males, aged between 18 and 24 years, who had gynaecomastia, hypogonadism or infertility. The predominant laboratory finding was a striking elevation of dehydroepiandrosterone sulphate (DHEAS) levels. The diagnosis of HSD deficiency was confirmed by finding a marked rise in dehydroepiandrosterone (DHEA) and 17-hydroxypregnenolone levels. In contrast to these findings in late-onset enzyme deficiency, in four males with the classical form of 21-hydroxylase deficiency the only sign was a reduction in adult height. The prevalence of late-onset HSD deficiency in men is not known and may be more relevant in patients with gynaecomastia or abnormal gonadal function than has hitherto been realized.

Immunohistochemical demonstration of steroid C21 hydroxylase in normal and neoplastic human breasts.

Steroid C21 hydroxylase was investigated immunohistochemically with the use of antibody against cytochrome P-450 specific for steroid C21 hydroxylation (P-450C21) in normal and neoplastic human breast tissues. In the histologically normal breast, P-450C21 was exclusively present in secretory tubules and ducts. In mammary dysplasia and fibroadenoma, P-450C21 was intensively stained in epithelial cells. In gynecomastia, P-450C21 was faintly observed in epithelial cells in some cases. In intraductal and invasive ductal carcinoma, P-450C21 was observed in the cells with ductal formation. P-450C21 was not observed in medullary and mucinous carcinoma. In lobular carcinoma, only two cases were positive for P-450C21 of nine cases examined. P-450C21 is considered to be closely related to the ductal differentiation in neoplastic transformation of the breast.

Increased aromatase activity in pubic skin fibroblasts from patients with isolated gynecomastia.

Aromatase activity (AR) was studied in pubic skin fibroblasts from eight patients with isolated gynecomastia (PSFG) and five normal subjects (PSFC). Cell monolayers were incubated in the presence of [3H]androstenedione (2 nM) for 4 or 24 h. Culture medium was extracted after addition of [14C] carriers to monitor recovery. Metabolites were separated by two successive chromatographic steps. Estrone (E1) and estradiol (E2) were characterized by crystallization, the other metabolites: 16-hydroxyestrone (16 alpha-OHE1) estriol (E3), and epiestriol (epiE3) by their chromatographic migration. AR was expressed either as femtomoles of E2 per microgram DNA (ARE2) or as total aromatized metabolites (ART = E1 + E2 + 16 alpha-OHE1 + E3 + epiE3/microgram DNA). After 4 h of incubation, no ARE2 could be measured in PSFC; it was low but significant in PSFG (0.03 +/- 0.02 (SEM) fmol/microgram DNA, P less than 0.01). The difference in ART was even more striking: 0.28 +/- 0.1 fmol/microgram DNA in PSFC, 3.15 +/- 2.88 in PSFG (P less than 0.05). 16 alpha-OHE1 represented in this latter group 62.5% of total aromatized metabolites vs. 39% in PSFC. After 24 h, ART was 4.17 +/- 3.70 and 1.02 +/- 0.42 fmol/microgram DNA in PSFG and PSFC, respectively (P less than 0.05); E3 + epiE3 represented 50% of the metabolites in both groups. In conclusion, AR is increased in PSFG relative to PSFC and an important oxidative metabolism of estrogens exists in both types of cells. This increased peripheral AR could result in increased formation of estrogens at the target cell site and represent an element of androgen-estrogen imbalance which would favor the development of gynecomastia.

Familial male pseudohermaphroditism with gynaecomastia due to 17 beta-hydroxysteroid dehydrogenase deficiency. A report of 3 cases.

Three sisters with male pseudohermaphroditism due to 17 beta-hydroxysteroid dehydrogenase deficiency are described. On the basis of a 46 XY karyotype and female phenotype all subjects were thought to have the testicular feminization syndrome. At puberty the two older patients developed signs of virilization and gynaecomastia. In these patients the plasma androstenedione level was 4-5 times higher than normal, whilst the plasma testosterone level was low compared to the normal range and, under basal conditions, their plasma androstenedione to testosterone ratio was 20-25 times higher than normal. Interestingly, in the third, prepubertal case, the basal androstenedione to testosterone ratio was normal but became six times higher than normal after hCG stimulation. These data support the diagnosis of male pseudohermaphroditism due to 17 beta-hydroxysteroid dehydrogenase deficiency and underline the diagnostic value of the hCG stimulation test prepubertally.