Antibody Arrays Identified Cycle-Dependent Plasma Biomarker Candidates of Peritoneal Endometriosis.

Endometriosis is an estrogen-dependent inflammatory disease affecting women in their reproductive age. Due to non-specific symptoms, women with endometriosis are often misdiagnosed or are accurately diagnosed only after several years. Diagnosis of peritoneal endometriosis is especially challenging and relies only on laparoscopic surgery. To date, different molecules have been proposed as potential non-invasive biomarkers of endometriosis; however, none have been confirmed as clinically useful. Therefore, this study aimed to discover novel plasma biomarker candidates for peritoneal endometriosis using an antibody array platform. This study included patients with endometriosis-like symptoms characterized by the absence (controls) or presence of peritoneal endometriosis (cases) after laparoscopic surgery and histological evaluation. Patients were further divided into secretory and proliferative groups, according to the phase of their menstrual cycle. Their plasma samples were collected and analyzed on an antibody array platform targeting more than 1350 proteins with over 1820 antibodies. In the proliferative group, the analysis revealed three differential proteins between cases and controls: ITB3, ITA2B2, and ACVL-1. In the secretory group, none of the examined proteins reached the log-fold change (logFC) and significance thresholds simultaneously. The potential of the identified differential proteins as plasma biomarker candidates for peritoneal endometriosis should be evaluated on a larger cohort, and their role in endometriosis should be investigated in further studies.

Transition metal-catalysed A-ring C-H activations and C(sp2)-C(sp2) couplings in the 13α-oestrone series and in vitro evaluation of antiproliferative properties.

Facile syntheses of 3-O-carbamoyl, -sulfamoyl, or -pivaloyl derivatives of 13α-oestrone and its 17-deoxy counterpart have been carried out. Microwave-induced, Ni-catalysed Suzuki-Miyaura couplings of the newly synthesised phenol esters with phenylboronic acid afforded 3-deoxy-3-phenyl-13α-oestrone derivatives. The carbamate and pivalate esters proved to be suitable for regioselective arylations. 2-(4-Substituted) phenyl derivatives were synthesised via Pd-catalysed, microwave-assisted C-H activation reactions. An efficient, one-pot, tandem methodology was elaborated for the introduction of the carbamoyl or pivaloyl group followed by regioselective C-2-arylation and subsequent removal of the directing group. The antiproliferative properties of the novel 13α-oestrone derivatives were evaluated in vitro on five human adherent cancer cell lines of gynaecological origin. 3-Sulfamate derivatives displayed substantial cell growth inhibitory potential against certain cell lines. The newly identified antiproliferative compounds having hormonally inactive core might be promising candidates for the design of more active anticancer agents.

Data on expression of genes involved in estrogen and progesterone action, inflammation and differentiation according to demographic, histopathological and clinical characteristics of endometrial cancer patients.

Endometrial cancer is the sixth most common cancer in women worldwide. It is associated with aberrant actions of steroid hormones, estrogens and progesterone, but also with enhanced inflammation and reduced cellular differentiation. Here, we show data on demographic and histopathological characteristics of 51 patients with endometrial cancer, together with data on correlations between the expression of 38 genes involved in estrogen and progesterone actions, inflammation and differentiation, and demographic characteristics. We also show data on changes in gene expression of these 38 genes according to histopathological and clinical characteristics of these patients. This article includes data referenced in the manuscript entitled ¼STAR and AKR1B10 are down-regulated in high-grade endometrial cancer by Sinreih et al. (in press) [1].

Structural basis for inhibition of 17ß-hydroxysteroid dehydrogenases by phytoestrogens: The case of fungal 17ß-HSDcl.

Phytoestrogens are plant-derived compounds that functionally and structurally mimic mammalian estrogens. Phytoestrogens have broad inhibitory activities toward several steroidogenic enzymes, such as the 17ß-hydroxysteroid dehydrogenases (17ß-HSDs), which modulate the biological potency of androgens and estrogens in mammals. However, to date, no crystallographic data are available to explain phytoestrogens binding to mammalian 17ß-HSDs. NADP(H)-dependent 17ß-HSD from the filamentous fungus Cochliobolus lunatus (17ß-HSDcl) has been the subject of extensive biochemical, kinetic and quantitative structure-activity relationship studies that have shown that the flavonols are the most potent inhibitors. In the present study, we investigated the structure-activity relationships of the ternary complexes between the holo form of 17ß-HSDcl and the flavonols kaempferol and 3,7-dihydroxyflavone, in comparison with the isoflavones genistein and biochanin A. Crystallographic data are accompanied by kinetic analysis of the inhibition mechanisms for six flavonols (3-hydroxyflavone, 3,7-dihydroxyflavone, kaempferol, quercetin, fisetin, myricetin), one flavanone (naringenin), one flavone (luteolin), and two isoflavones (genistein, biochanin A). The kinetics analysis shows that the degree of hydroxylation of ring B significantly influences the overall inhibitory efficacy of the flavonols. A distinct binding mode defines the interactions between 17ß-HSDcl and the flavones and isoflavones. Moreover, the complex with biochanin A reveals an unusual binding mode that appears to account for its greater inhibition of 17ß-HSDcl with respect to genistein. Overall, these data provide a blueprint for identification of the distinct molecular determinants that underpin 17ß-HSD inhibition by phytoestrogens.

Pyrithione-based ruthenium complexes as inhibitors of aldo-keto reductase 1C enzymes and anticancer agents.

Four ruthenium complexes of clinically used zinc ionophore pyrithione and its oxygen analog 2-hydroxypyridine N-oxide were prepared and evaluated as inhibitors of enzymes of the aldo-keto reductase subfamily 1C (AKR1C). A kinetic study assisted with docking simulations showed a mixed type of inhibition consisting of a fast reversible and a slow irreversible step in the case of both organometallic compounds 1A and 1B. Both compounds also showed a remarkable selectivity towards AKR1C1 and AKR1C3 which are targets for breast cancer drug design. The organoruthenium complex of ligand pyrithione as well as pyrithione itself also displayed toxicity on the hormone-dependent MCF-7 breast cancer cell line with EC50 values in the low micromolar range.

Panels of cytokines and other secretory proteins as potential biomarkers of ovarian endometriosis.

Endometriosis is a gynecologic disease that is characterized by nonspecific symptoms and invasive diagnostics. To date, there is no adequate noninvasive method for the diagnosis of endometriosis. Although more than 100 potential biomarkers have been investigated in blood and/or peritoneal fluid, none of these has proven useful in clinical practice. The aim to find a suitable panel of biomarkers that would allow noninvasive diagnosis thus remains of interest. We evaluated the concentrations of 16 cytokines and other secretory proteins in serum and peritoneal fluid of 58 women with ovarian endometriosis (cases) and 40 healthy women undergoing sterilization or patients with benign ovarian cysts (controls) using multiplexed double fluorescence-based immunometric assay platform and enzyme-linked immunosorbent assay. Significantly higher concentrations of glycodelin-A were shown in serum, and significantly higher levels of glycodelin-A, IL-6, and IL-8, and lower levels of leptin were measured in the peritoneal fluid of cases versus controls. In serum, the best performance was shown by models that included the ratio of leptin/glycodelin-A and the ratio of ficolin 2/glycodelin-A, whereas in the peritoneal fluid the best models included the ratio of biglycan/leptin, regulated on activation normal T-cell expressed and secreted/IL-6 and ficolin-2/glycodelin-A, and IL-8 per milligram of total protein, all in combination with age. The models using serum and peritoneal fluid distinguished between ovarian endometriosis patients and controls regardless of the menstrual cycle phase with relatively high sensitivity (72.5% to 84.2%), specificity (78.4% to 91.2%), and area under the curve (0.85 to 0.90).

Combined liquid chromatography-tandem mass spectrometry analysis of progesterone metabolites.

Progesterone has a number of important functions throughout the human body. While the roles of progesterone are well known, the possible actions and implications of progesterone metabolites in different tissues remain to be determined. There is a growing body of evidence that these metabolites are not inactive, but can have significant biological effects, as anesthetics, anxiolytics and anticonvulsants. Furthermore, they can facilitate synthesis of myelin components in the peripheral nervous system, have effects on human pregnancy and onset of labour, and have a neuroprotective role. For a better understanding of the functions of progesterone metabolites, improved analytical methods are essential. We have developed a combined liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection and quantification of progesterone and 16 progesterone metabolites that has femtomolar sensitivity and good reproducibility in a single chromatographic run. MS/MS analyses were performed in positive mode and under constant electrospray ionization conditions. To increase the sensitivity, all of the transitions were recorded using the Scheduled MRM algorithm. This LC-MS/MS method requires small sample volumes and minimal sample preparation, and there is no need for derivatization. Here, we show the application of this method for evaluation of progesterone metabolism in the HES endometrial cell line. In HES cells, the metabolism of progesterone proceeds mainly to (20S)-20-hydroxy-pregn-4-ene-3-one, (20S)-20-hydroxy-5α-pregnane-3-one and (20S)-5α-pregnane-3α,20-diol. The investigation of possible biological effects of these metabolites on the endometrium is currently undergoing.

The characterization of the human nasal epithelial cell line RPMI 2650 under different culture conditions and their optimization for an appropriate in vitro nasal model.

PURPOSE: The further characterization of the cell line RPMI 2650 and the evaluation of different culture conditions for an in vitro model for nasal mucosa. METHODS: Cells were cultured in media MEM or A-MEM at air-liquid (A-L) or liquid-liquid (L-L) interfaces for 1 or 3 weeks. Different cryopreservation methods and cell culture techniques were evaluated with immunolabelling of junctional proteins, ultrastructural analysis using electron microscopy, transepithelial electrical resistance (TEER) measurements, permeation studies with dextran and jacalin, and gene expression profiling of 84 drug transporters. RESULTS: Cell proliferation and differentiation depended on the used medium. The established epithelia expressed occludin, claudin-1, and E-cadherin under all conditions. Cells grown at the A-L interface formed more layers and exhibited a higher TEER and lower dextran and jacalin permeability than at the L-L interface, where cells morphologically exhibited a more differentiated phenotype. The expression of ABC and SLC transporters depended on culture duration and interface. CONCLUSIONS: The RPMI 2650 cells form a polarized epithelium resembling nasal mucosa. However, different culture conditions have a significant effect on cell ultrastructure, barrier integrity, and gene expression, and should be considered when using this cell line as an in vitro model for drug permeability studies and screening of nasal drug candidates.

Noninvasive biomarkers of endometriosis: myth or reality?

Endometriosis affects 10% of premenopausal women and 35-50% of women with infertility, pelvic pain, or both. At present, endometriosis can only be diagnosed with surgery, where laparoscopy is considered a gold standard. Noninvasive biomarkers are thus urgently needed. In 2010, the peripheral biomarkers of endometriosis were systematically reviewed by May et al. However, with the introduction of '-omics' technologies, we have witnessed immense progress in biomarker discovery, which now calls for an overview of recent studies. This report looks at potential blood and urine biomarkers of endometriosis published in the last 3 years. The current status of noninvasive diagnostic biomarkers of endometriosis is discussed, with the limitations of these studies identified and recommendations for future biomarker discovery provided.

Disturbed balance between phase I and II metabolizing enzymes in ovarian endometriosis: a source of excessive hydroxy-estrogens and ROS?

Oxidative metabolism of estrogens was studied in 31 ovarian endometriosis and 29 normal endometrium samples, by qPCR. Expression was monitored for genes encoding five estrogen hydroxylating, five hydroxy (OH)-estrogen conjugating, and three estrogen quinone detoxifying enzymes. CYP1B1, COMT, NQO1, and GSTP1 protein levels were determined using Western blotting and immunohistochemistry staining. Increased expression of CYP1A1, CYP3A7 and COMT, and higher levels of MB-COMT were seen in endometriosis, as compared to normal endometrium. Expression of CYP1B1, CYP3A5, SULT1A1 and NQO2 was unchanged, with comparable CYP1B1 protein levels. Expression of SULT1E1, SULT2B1, UGT2B7, NQO1, and GSTP1 was decreased. Three NQO1 isoforms were detected; NQO1c appears to be endometriosis-specific. Our data indicate a disturbed balance between phase I and II metabolizing enzymes in endometriosis, potentially leading to excessive OH-estrogen and altered ROS formation, and stimulation of proliferation of ectopic endometrium. This is the first report on disturbed expression of estrogen oxidative metabolism genes in ovarian endometriosis.

Decreased levels of AKR1B1 and AKR1B10 in cancerous endometrium compared to adjacent non-cancerous tissue.

Endometrial cancer is associated with enhanced cell proliferation due to high concentrations of estrogens, and decreased cell differentiation due to low levels of progesterone and retinoic acid. It is also associated with aberrant inflammatory responses and concomitant increased production of prostaglandins. The human members of the aldo-keto reductase 1B (AKR1B) subfamily, AKR1B1 and AKR1B10, have roles in these processes and can thus be implicated in endometrial cancer. To date, there have been no reports on the expression of AKR1B1 in endometrial cancer, while AKR1B10 has only been studied at the cellular level. To evaluate the roles of these AKR1B enzymes, we investigated expression of AKR1B1 and AKR1B10 in 47 paired samples of cancerous and adjacent control endometrium at the mRNA and protein levels, by quantitative PCR, Western blotting and immunohistochemistry staining. There were significantly lower mRNA and protein levels of AKR1B1 in cancerous tissues compared to adjacent endometrium. The gene expression of AKR1B10 at the mRNA level was significantly increased, while there were significantly decreased protein levels. Immunohistochemistry revealed that both of these enzymes were present in all of the samples, and are located in epithelial cells of cancerous and control endometrial glands. Elevated levels in adjacent non-cancerous tissues imply that these enzymes are more important in the initiation of endometrial cancer than in its progression. To the best of our knowledge, this is the first report on the expression of AKR1B1 and AKR1B10 in endometrial cancer. Further studies are needed to define the precise roles of these enzymes in the pathogenesis of endometrial cancer.

Progestin effects on expression of AKR1C1-AKR1C3, SRD5A1 and PGR in the Z-12 endometriotic epithelial cell line.

Endometriosis is defined as the presence of endometrial glands and stroma outside the uterine cavity. This disease is associated with diminished protective effects of progesterone, which are usually explained by inadequate activation of progesterone receptors and also enhanced pre-receptor metabolism of progesterone. Endometriosis is often treated with progestins, which act as progesterone receptor agonists, although their exact mechanisms of action are not completely understood. The aim of the present study was to investigate how the progestins medroxyprogesterone acetate, dydrogesterone and dienogest, as well as progesterone, impact on the expression of genes of pre-receptor progesterone metabolism in Z-12 epithelial cell line, a model system of peritoneal endometriosis. Our data demonstrate that these progestins affect local pre-receptor metabolism to a different extent. The most favorable effects were seen for dydrogesterone and dienogest, where the first, dydrogesterone, significantly reduced SRD5A1, AKR1C2 and AKR1C3 expression, and additionally had a nonsignificant impact on progesterone receptor B (PR-B) protein levels. This might slow down the first step of pre-receptor metabolism, the conversion of progesterone to 5α-dihydroprogestrone by SRD5A1, and it might also affect further reduction of 3-keto and 20-keto groups catalyzed by AKR1C2 and AKR1C3. Similarly favorable effects were seen for dienogest, which promoted significant reduction of AKR1C1 and AKR1C2 expression and also showed no effect on PR-B protein levels. Different effects were seen for progesterone, which significantly decreased SRD5A1, PR-B and HSD17B2 protein levels. In contrast, treatment with medroxyprogesterone acetate resulted in increased AKR1C1 expression and decreased levels of PR-B, which might lead to enhanced progesterone metabolism and reduced signaling through progesterone receptors. Altogether, our data in this Z-12 cell model suggest that the beneficial effects of treatment with progestin observed in endometriosis patients might arise from decreased pre-receptor metabolism of the protective progesterone by the SRD5A1 and AKR1C enzymes.

Selective inhibitors of aldo-keto reductases AKR1C1 and AKR1C3 discovered by virtual screening of a fragment library.

Human aldo-keto reductases 1C1-1C4 (AKR1C1-AKR1C4) function in vivo as 3-keto-, 17-keto-, and 20-ketosteroid reductases and regulate the activity of androgens, estrogens, and progesterone and the occupancy and transactivation of their corresponding receptors. Aberrant expression and action of AKR1C enzymes can lead to different pathophysiological conditions. AKR1C enzymes thus represent important targets for development of new drugs. We performed a virtual high-throughput screen of a fragment library that was followed by biochemical evaluation on AKR1C1-AKR1C4 enzymes. Twenty-four structurally diverse compounds were discovered with low µM K(i) values for AKR1C1, AKR1C3, or both. Two structural series included the salicylates and the N-phenylanthranilic acids, and additionally a series of inhibitors with completely novel scaffolds was discovered. Two of the best selective AKR1C3 inhibitors had K(i) values of 0.1 and 2.7 µM, exceeding expected activity for fragments. The compounds identified represent an excellent starting point for further hit-to-lead development.

Expression of human aldo-keto reductase 1C2 in cell lines of peritoneal endometriosis: potential implications in metabolism of progesterone and dydrogesterone and inhibition by progestins.

The human aldo-keto reductase AKR1C2 converts 5α-dihydrotestosterone to the less active 3α-androstanediol and has a minor 20-ketosteroid reductase activity that metabolises progesterone to 20α-hydroxyprogesterone. AKR1C2 is expressed in different peripheral tissues, but its role in uterine diseases like endometriosis has not been studied in detail. Some progestins used for treatment of endometriosis inhibit AKR1C1 and AKR1C3, with unknown effects on AKR1C2. In this study we investigated expression of AKR1C2 in the model cell lines of peritoneal endometriosis, and examined the ability of recombinant AKR1C2 to metabolise progesterone and progestin dydrogesterone, as well as its potential inhibition by progestins. AKR1C2 is expressed in epithelial and stromal endometriotic cell lines at the mRNA level. The recombinant enzyme catalyses reduction of progesterone to 20α-hydroxyprogesterone with a 10-fold lower catalytic efficiency than the major 20-ketosteroid reductase, AKR1C1. AKR1C2 also metabolises progestin dydrogesterone to its 20α-dihydrodydrogesterone, with 8.6-fold higher catalytic efficiency than 5α-dihydrotestosterone. Among the progestins that are currently used for treatment of endometriosis, dydrogesterone, medroxyprogesterone acetate and 20α-dihydrodydrogesterone act as AKR1C2 inhibitors with low µM K(i) values in vitro. Their potential in vivo effects should be further studied.

Insights into subtle conformational differences in the substrate-binding loop of fungal 17ß-hydroxysteroid dehydrogenase: a combined structural and kinetic approach.

The 17ß-HSD (17ß-hydroxysteroid dehydrogenase) from the filamentous fungus Cochliobolus lunatus (17ß-HSDcl) is a NADP(H)-dependent enzyme that preferentially catalyses the interconversion of inactive 17-oxo-steroids and their active 17ß-hydroxy counterparts. 17ß-HSDcl belongs to the SDR (short-chain dehydrogenase/reductase) superfamily. It is currently the only fungal 17ß-HSD member that has been described and represents one of the model enzymes of the cP1 classical subfamily of NADPH-dependent SDR enzymes. A thorough crystallographic analysis has been performed to better understand the structural aspects of this subfamily and provide insights into the evolution of the HSD enzymes. The crystal structures of the 17ß-HSDcl apo, holo and coumestrol-inhibited ternary complex, and the active-site Y167F mutant reveal subtle conformational differences in the substrate-binding loop that probably modulate the catalytic activity of 17ß-HSDcl. Coumestrol, a plant-derived non-steroidal compound with oestrogenic activity, inhibits 17ß-HSDcl [IC50 2.8 µM; at 100 µM substrate (4-oestrene-3,17-dione)] by occupying the putative steroid-binding site. In addition to an extensive hydrogen-bonding network, coumestrol binding is stabilized further by π-π stacking interactions with Tyr212. A stopped-flow kinetic experiment clearly showed the coenzyme dissociation as the slowest step of the reaction and, in addition to the low steroid solubility, it prevents the accumulation of enzyme-coenzyme-steroid ternary complexes.

Discovery of highly potent, nonsteroidal 17ß-hydroxysteroid dehydrogenase type 1 inhibitors by virtual high-throughput screening.

17ß-Hydroxysteroid dehydrogenase type 1 (17ß-HSD1) catalyzes the formation of the potent proliferation-stimulating hormone estradiol, and it is thus involved in the development of hormone-dependent breast cancer. Due to its high substrate specificity and the known relationships between its overexpression and disease incidence, 17ß-HSD1 is considered an attractive target for drug development. Here, we have used structure-based virtual high-throughput screening to successfully identify potent nonsteroidal 17ß-HSD1 inhibitors. Computational screening of a drug-like database containing 13 million compounds identified hits with a 2-benzylidenebenzofuran-3(2H)-one scaffold that we show to be highly potent 17ß-HSD1 inhibitors. The most potent in the series, compound 1, showed an IC(50) of 45nM in our 17ß-HSD1 inhibition assay, and also showed good selectivity for 17ß-HSD1 over 17ß-HSD2.

Novel inhibitors of trihydroxynaphthalene reductase with antifungal activity identified by ligand-based and structure-based virtual screening.

Curvularia lunata is a dark pigmented fungus that is the causative agent of several diseases in plants and in both immunodeficient and immunocompetent patients. 1,8-Dihydroxynaphthalene-melanin is found in the cell wall of C. lunata and is believed to be the important virulence factor of dematiaceous fungi. Trihydroxynaphthalene reductase is an enzyme of the 1,8-dihydroxynaphthalene-melanin biosynthetic pathway, and it thus represents an emerging target for the development of novel fungicides and antimycotics. In the present study, we describe novel inhibitors of trihydroxynaphthalene reductase from C. lunata. These inhibitors were identified by ligand-based three-dimensional similarity searching and docking to a homology-built model and by subsequent biochemical and antifungal evaluation. Discovery of competitive inhibitors with K(i) values in low micromolar and even nanomolar concentration range proves the aplicability of homology-built model of 3HNR for hit finding by virtual screening methods.

Discovery of new inhibitors of aldo-keto reductase 1C1 by structure-based virtual screening.

Aldo-keto reductase 1C1 is a hydroxysteroid dehydrogenase that inactivates progesterone by converting it to 20alpha-hydroxyprogesterone. It also inactivates 3alpha,5alpha-tetrahydroprogesterone, an allosteric modulator of the gamma-aminobutyric acid receptor that has anaesthetic, analgesic, anxiolytic and anti-convulsant effects. Inhibitors of aldo-keto reductase 1C1 are thus very interesting as potential agents for the treatment of endometrial cancer, premenstrual syndrome, catamenial epilepsy, and depressive disorders, and for the maintenance of pregnancy. We have used the molecular docking program eHiTS for virtual screening of 1990 compounds from the National Cancer Institute "Diversity Set". Fifty compounds with the highest predicted binding energies were then evaluated in vitro. Three structurally diverse hits were obtained that inhibit aldo-keto reductase 1C1 in the low micromolar range of IC(50) values. These hits represent promising starting points for structural optimization in hit-to-lead development.

Flavonoids and cinnamic acid derivatives as inhibitors of 17beta-hydroxysteroid dehydrogenase type 1.

17beta-Hydroxysteroid dehydrogenase (17beta-HSD) type 1 converts estrone to estradiol, a potent ligand for estrogen receptors. It represents an important target for the development of drugs for treatment of estrogen-dependent diseases. In the present study, we have examined the inhibitory activities of some flavonoids, their biosynthetic precursors (cinnamic acids and coumaric acid), and their derivatives. The proliferative activity of flavonoids on the T-47D estrogen-receptor-positive breast cancer cell line was also evaluated. Among 10 flavonoids, 7,4'-dihydroxyflavone, diosmetin, chrysoeriol, scutellarein, genkwanin and fisetin showed more than 70% inhibition of 17beta-HSD type 1 at 6microM. In a series of 18 derivatives of cinnamic acid, the best inhibitor was 4'-cyanophenyl 3,4-methylenedioxycinnamate, with more than 70% inhibition of 17beta-HSD type 1. None of flavonoids affected the proliferation of T-47D breast cancer cells.