Case report: whole exome sequencing of primary cardiac angiosarcoma highlights potential for targeted therapies.

Background: Primary cardiac angiosarcomas are rare, but they are the most aggressive type of primary cardiac neoplasms. When patients do present, it is with advanced pulmonary and/or cardiac symptoms. Therefore, many times the correct diagnosis is not made at the time of initial presentation.

The farnesoid X receptor regulates transcription of 3beta-hydroxysteroid dehydrogenase type 2 in human adrenal cells.

Recent studies have shown that the adrenal cortex expresses high levels of farnesoid X receptor (FXR), but its function remains unknown. Herein, using microarray technology, we tried to identify candidate FXR targeting genes in the adrenal glands, and showed that FXR regulated 3beta-hydroxysteroid dehydrogenase type 2 (HSD3B2) expression in human adrenocortical cells. We further demonstrated that FXR stimulated HSD3B2 promoter activity and have defined the cis-element responsible for FXR regulation of HSD3B2 transcription.

Estrogen related receptor-alpha enhances surfactant protein-A gene expression in fetal lung type II cells.

Surfactant protein-A (SP-A) gene expression is developmentally regulated in fetal lung type II cells in concert with surfactant glycerophospholipid synthesis. In studies using transfected type II cells, we characterized a nuclear receptor element (NRE(SP-A), 5'-TGACCTTA-3') at -242 bp in the 5'-flanking sequence of human SP-A2 (hSP-A) gene that is essential for basal and cAMP-induced expression. NRE(SP-A) has high sequence similarity to the consensus binding site for estrogen-related receptor (ERR).

Temporal and spatial expression of liver receptor homologue-1 (LRH-1) during embryogenesis suggests a potential role in gonadal development.

Liver receptor homologue-1 (LRH-1), an orphan member of the nuclear receptor family highly expressed in adult mouse ovary, is closely related to steroidogenic factor 1 (SF-1), known to be important in gonadal formation. To analyze the potential role of LRH-1 in gonadal differentiation, we compared LRH-1 and SF-1 expression during mouse embryonic and postnatal development. LRH-1 expression was first detected in the urogenital ridge before sexual determination, in primordial germ cells and surrounding somatic cells; expression persisted after differentiation into testes and ovaries.

Transcriptional regulation of aromatase in placenta and ovary.

Our goal is to define the cellular and molecular mechanisms for tissue- and cell-specific, developmental and hormonal regulation of the human CYP19 (aromatase P450/P450arom) gene in estrogen-producing cells. In this article, we review studies using transgenic mice and transfected cells to identify genomic regions and response elements that mediate CYP19 expression in placenta and ovary, as well as to define the molecular mechanisms for O2 regulation of differentiation and CYP19 gene expression in human trophoblast cells in culture. We also highlight recent findings regarding LRH-1 versus SF-1 mRNA expression and cellular localization in the mouse ovary during the estrous cycle and various stages of pregnancy.

Expression of LRH-1 and SF-1 in the mouse ovary: localization in different cell types correlates with differing function.

Steroid biosynthesis in ovary is enhanced by the orphan nuclear receptor, steroidogenic factor-1 (SF-1); however, we reported that liver receptor homolog-1 (LRH-1), a closely related receptor to SF-1, is also expressed in mouse ovary. To further investigate the role of LRH-1 in mouse ovary, we used in situ hybridization to identify the cell types that express LRH-1 versus SF-1, and carried out functional studies to determine the role of LRH-1 in the regulation of the human (h) ovary-specific CYP19 promoter. LRH-1 expression was found to be abundant and highly restricted to cells involved in estrogen biosynthesis-granulosa cells during the estrous cycle, and in corpora lutea (CL) of pregnancy.

Mechanisms in tissue-specific regulation of estrogen biosynthesis in humans.

In humans, aromatase P450, which catalyses conversion of C(19)-steroids to estrogens, is expressed in several tissues, including gonads, brain, adipose tissue, skin and placenta, and is encoded by a single-copy gene (CYP19); however, this does not hold true for all species. The human gene is approximately 130 kb and its expression is regulated, in part, by tissue-specific promoters and by alternative splicing mechanisms. Using transgenic mouse technology, it was observed that ovary-, adipose tissue- and placenta-specific expression of human CYP19 is directed by relatively small segments of DNA within 500 bp upstream of each of the tissue-specific first exons.

Tissue-specific expression of the human CYP19 (aromatase) gene in ovary and adipose tissue of transgenic mice.

In humans, the CYP19 (aromatase P450) gene is expressed in a number of tissues, including gonads, placenta, adipose tissue, skin and brain. The 5'-untranslated regions (UTR) of CYP19 mRNA transcripts in these tissues are encoded by different tissue-specific first exons, which are alternatively spliced onto a common site just upstream of the start of translation in exon II. In ovary, the 5'-UTR of CYP19 transcripts is encoded by exon IIa, which lies just upstream of exon II, while in adipose, the 5'-UTR of CYP19 transcripts is encoded by exon I.

Mammalian aromatases.

Aromatase is the enzyme complex that catalyses the synthesis of oestrogens from androgens, and therefore it has unique potential to influence the physiological balance between the sex steroid hormones. Both aromatase cytochrome P450 (P450arom) and NADPH-cytochrome P450 reductase (reductase), the two essential components of the enzyme complex, are highly conserved among mammals and vertebrates. Aromatase expression occurs in the gonads and brain, and is essential for reproductive development and fertility.

A 278 bp region just upstream of the human CYP19 (aromatase) gene mediates ovary-specific expression in transgenic mice.

In humans, the CYP19 gene, which encodes aromatase P450, is expressed in a number of tissues including gonads, adipose, bone, and placenta. The 5'-untranslated regions (UTR) of CYP19 mRNA transcripts in these tissues are encoded by different tissue-specific first exons, which are alternatively spliced onto a common site just upstream of the start site of translation in exon II. In ovary, the 5'-UTR of CYP19 transcripts is encoded by exon IIa, which lies just upstream of exon II.

The 5'-flanking region of the ovarian promoter of the bovine CYP19 gene contains a deletion in a cyclic adenosine 3',5'-monophosphate-like responsive sequence.

Conversion of C19 steroids to estrogens is catalyzed by aromatase P450 (P450arom; the product of the CYP19 gene). In the ovary, P450arom is expressed in granulosa cells of both human (h) and bovine (b) follicles. After the ovulatory surge of gonadotropins, however, P450arom expression is maintained only in the luteinized granulosa cells of the human ovary and is absent from the bovine corpus luteum.

A putative binding site for Sp1 is involved in transcriptional regulation of CYP17 gene expression in bovine ovary.

In the bovine ovary, thecal cells are the only cell type capable of expressing the CYP17 gene in response to LH. With the onset of ovulation and luteinization in the cow, there is complete loss of P450c17alpha expression. To characterize the molecular mechanisms involved in tissue-specific regulation of the CYP17 gene in the bovine ovary, deletion mutations of the bovine CYP17 promoter were ligated into a promoterless luciferase expression vector, and reporter constructs were transiently transfected into primary cultures of bovine thecal and luteal cells.

Porcine aromatases: studies on tissue-specific, functionally distinct isozymes from a single gene?

Aromatase cytochrome P450 (P450arom) is expressed in a variety of tissues. Pigs express P450arom as bilaminar blastocysts in utero, and thereafter in the gonads, adrenal glands and placenta. Our studies also demonstrate the existence of porcine isozymes of P450arom which differ substantially in their amino acid composition and function.

Regulation of aromatase expression in the ovary and placenta: a comparison between two species.

The conversion of C19 steroids to estrogens is catalysed by aromatase P450 (P450arom; product of the CYP19 gene). Tissue sites of expression include the gonads and brain; however, in a small subset of mammals, P450arom is also expressed in the placenta. In humans, gonadal expression employs a promoter proximal to the start site of translation, whereas expression in the placenta relies on a promoter which is distal to this site.

Endocrine disorders associated with inappropriately high aromatase expression.

Aromatase P450 (P450arom) is responsible for conversion of C19 steroids to estrogens in a number of human tissues, such as the placenta, gonads, adipose tissue, skin and the brain. Aromatase expression in human tissues is regulated by use of alternative promoters in the placenta (promoter I.1), adipose tissue (promoters I.

Prostaglandin E2 stimulates aromatase expression in endometriosis-derived stromal cells.

C19 steroids are converted to estrogens by aromatase P450 (P450arom). Aromatase expression in humans is regulated by use of tissue-specific promoters in the placenta (promoter I.1), adipose tissue (promoters I.

Aromatase expression in health and disease.

Family 19 of the P450 superfamily is responsible for the conversion of C19 androgenic steroids to the corresponding estrogens, a reaction known as aromatization, since it involves conversion of the delta 4-3-one A-ring of the androgens to the corresponding phenolic A-ring characteristic of estrogens. Its members occur throughout the entire vertebrate phylum. The reaction mechanism of aromatase is very interesting from a chemical point of view and has been studied extensively; however, a detailed examination of structure-function relationships has not been possible due to lack of a crystal structure.

Cytochromes P450 11: expression of the CYP19 (aromatase) gene: an unusual case of alternative promoter usage.

Family 19 of the P450 super family is responsible for the conversion of C19 androgenic steroids to the corresponding estrogens, a reaction known as aromatization because it involves conversion of the delta4-3-one A-ring of the androgens to the corresponding phenolic A-ring characteristic of estrogens. The gene encoding human aromatase has been cloned and characterized and shown to be unusual compared to genes encoding other P450 enzymes, because there are numerous untranslated first exons that occur in aromatase transcripts in a tissue-specific fashion due to differential splicing as a consequence of the use of tissue-specific promoters. Thus, expression in the ovary uses a proximal promoter that is regulated primarily by cAMP.

Functional aromatase expression in porcine adrenal gland and testis.

The expression of aromatase cytochrome P450 (P450arom) in the adrenal glands, testes, and placentas of fetal and newborn pigs was investigated. Western immunoblot analysis detected a single 48-50-kDa protein band in these tissues as well as in other porcine tissues known to express P450arom including Day 12 tubular conceptuses, theca interna, and granulosa. Slight differences in migration suggested that the P450arom protein expressed in the testis was larger than that in the adrenal gland, which was, in turn, larger than that in placenta, theca, and granulosa.

Demonstration of tissue-specific promoters in nonprimate species that express aromatase P450 in placentae.

Conversion of androgens to estrogens is catalyzed by aromatase P450 (P450arom; the product of the CYP19 gene). Regulation of tissue-specific expression of P450arom in humans is due, in part, to alternative transcriptional start sites that arise as a consequence of the use of granulosa cells and placental tissue from cows, horses, and pigs (ungulates) in order to determine whether these species, like the human, utilize tissue-specific promoters to drive P450arom expression. The majority of transcripts in the placenta have 5'-termini that differ from those in the ovary upstream of a common site of divergence, indicative of a splice junction.

Isolation and characterization of a complementary deoxyribonucleic acid insert encoding bovine aromatase cytochrome P450.

Aromatase, an enzyme complex comprised of aromatase cytochrome P450 (P450arom; the product of the CYP19 gene) and the flavoprotein NADPH-cytochrome P450 reductase, catalyzes the conversion of androgens to estrogens. Three cDNA inserts encoding P450arom were isolated from a bovine placental cDNA library. These inserts were sequenced and found to correspond closely to human P450arom sequence from the internal EcoRI restriction site (exon III) through the termination codon (exon X) into the 3'-untranslated region.

Superovulation in cattle: effects of purity of FSH preparation on follicular characteristics in vivo.

When cattle were superovulated with an FSH preparation containing no detectable LH (FSH-W), more viable embryos were recovered as compared with a standard preparation containing LH (FSH-P), with no change in the total number of ova + embryos recovered (Donaldson et al., 1986). To determine the basis for the increased embryo viability, we compared numbers of developing follicles and concentrations of estradiol in their follicular fluid at two times during the course of superovulatory treatment with FSH-P vs.

Effects of charcoal-extracted follicular fluid on reproductive function in postpartum cows.

In order to determine the role of follicle-stimulating hormone (FSH) on the resumption of ovarian function in cows early postpartum (PP), bovine follicular fluid (FF) was used to selectively suppress concentrations of FSH. Calves were removed from all cows within 24 hr of birth. Follicular fluid that was treated with charcoal to remove steroids (15 ml; n = 14) or serum (S) from an ovariectomized cow (15 ml, n = 14) was injected i.

The effect of exogenous melatonin administration on gonadotropin and prolactin patterns in ovariectomized estradiol-treated heifers exposed to increasing photoperiod.

Eight nulliparous Angus and Angus crossbred heifers, which had been ovariectomized and treated with estradiol-17beta (E(2)) S.Q. implants for 6 months, were used to determine the effects of exogenous melatonin on serum gonadotropin and prolactin concentrations.