Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.6.1 (sulfatase)
3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Arylsulfatase C (aryl-sulfate sulfohydrolase, EC 3.1.6.1) from sheep brain acetone powder was solubilized with the chaotropic agent, KSCN. Anti-chaotropes such as (NH4)2SO4 or sodium citrate significantly enhanced the activity of the solubilized enzyme indicating that hydrophobicity was an important factor influencing the enzyme activity. Dialysis or gel filtration of the solubilized enzyme resulted in a marked loss of activity. 3a dialyzable activator could reconstitute the activity in the presence of the antichaotropes. The activator was purified partially and preliminary studies indicated it to be a low molecular weight peptide. Arylsulfatase C and estrone sulfatase activities were compared in the solubilized enzyme. Estrone sulfatase activity was also increased in the presence of antichaotropes at lower concentration in comparison to arylsulfatase C. It however did not show a requirement for the dialyzable activator. Kinetic studies showed that elevation of enzyme activity by the antichaotropes and activator in the case of arylsulfatase C and by antichaotropes in the case of estrone sulfatase was due to an increase in V with a decrease in Km.
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PMID:Studies on the chaotropically solubilized arylsulfatase C and estrone sulfatase of sheep brain. 45 22

Placental steroid sulfatase deficiency is a genetic disorder only recently reported in the medical literature. Most documented cases of placental sulfatase deficiency have been marked by delay in onset of labor, lack of cervical dilatation, and relative refractoriness of oxytocic agents and amniotomy. We have studied the placenta, cultured fibroblasts, and amniotic fluid cells from an affected patient. The activities of estrone sulfatase, pregnenolone sulfatase, dehydroepiandrosterone sulfatase, and arylsulfatase C in the placenta from the patient were severely deficient. Arylsulfatases A and B were present at levels within the normal range for this tissue. Fibroblast dehydroepiandrosterone sulfatase activity was virtually absent in the patient's cells and present at normal levels in individuals with a variety of lysosomal disorders. It would thus appear that the mutation responsible for steroid sulfatase deficiency is genetically and biochemically distinct from those involved in the lysosomal sulfatase deficiency states. The cell culture studies further suggest that the defect is a generalized one which should be detectable in midtrimester of pregnancy and may have phenotypic consequences in later postnatal life.
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PMID:Steroid sulfatase deficiency. 88 10

Of the total number of breast cancers approx. 30-50% are hormone-dependent and estradiol is one of the main factors of cancerization. Consequently, the control of this hormone inside the cancer cell is of capital importance because it is well established that the inhibition of estradiol biosynthesis can have a positive effect on the evolution of the disease. The blockage of estradiol can be obtained by the action of anti-aromatases, anti-sulfatases, the control of the 17 beta-hydroxysteroid dehydrogenase activity or by the stimulation of the sulfotransferase which converted the estrogens in their sulfates. In breast cancer tissue estrone sulfate is quantitatively the most important source of estradiol. In the intact cell, estrone sulfatase activity is very intense in the hormone-dependent cell lines (e.g. MCF-7, T-47D) but very small activity is observed in the hormone-independent (e.g. MDA-MB-231, MDA-MB-436) cell lines. However, this activity became very strong after homogenization in the hormone-independent cells, suggesting the presence of repressive factor(s) for this enzyme or its sequestering in an inactive form, in the intact cells of these cell lines. In a series of previous studies it was found that in hormone-dependent cell lines different anti-estrogens: tamoxifen and derivatives, ICI 164,384, very significantly decrease the estradiol concentration originated from estrone sulfate, and recently it was observed that Decapeptyl (D-Trp6-gonadotropin-releasing hormone) in the presence of heparin can also decrease the conversion of estrone sulfate into estradiol. No significant effect was obtained in the presence of heparin or Decapeptyl alone. The estrone sulfatase activity can be inhibited by progesterone, the progestagen R-5020, and testosterone. In another series of recent studies the presence of very strong estrogen sulfotransferase activity has been shown in one breast cancer cell line, the MDA-MB-468. We can conclude that: (1) the control of estradiol concentration can be carried out in the breast cancer tissue itself; (2) estrone sulfate can play an important role in the bioavailability of estradiol in the breast cancer cell; and (3) as is the case for the aromatase, the control of: the estrogen sulfatase, estrogen sulfotransferase, and 17 beta-hydroxysteroid dehydrogenase can be new targets for therapeutic applications in breast cancer.
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PMID:Recent data on estrogen sulfatases and sulfotransferases activities in human breast cancer. 158 Sep 21

The effect of progesterone and nine synthetic progestogens on the activity rate of microsome estrone sulfatase obtained from human breast carcinoma tissues was studied. The progestogens were classified into three groups: group I with a strict inhibitor effect: demegestone and chlormadinone acetate; group II with a strict activator effect: medroxyprogesterone acetate, quingestanol acetate, lynestrenol and progesterone and group III with a nonsignificant effect: dydrogesterone, promegestone, norgestrel and danazol. Demegestone was the most potent inhibitor and medroxyprogesterone acetate and quingestanol acetate had the highest activator effect. The effect of Triton X-100, a nonionic detergent, was also tested. This detergent consistently increased the microsome estrone sulfatase activity. A comparison was made between the effects of demegestone, medroxyprogesterone acetate and danazol on estrone sulfatase activity measured with or without Triton X-100 in the incubation medium. The presence of the detergent modified the progestogen action. Our results suggest that synthetic progestogens can influence the estrone sulfatase activity measured in human breast carcinoma tissues. However, the effect of progestogens was dependent on experimental conditions. Progestogens such as demegestone and chlormadinone acetate which inhibited estrone sulfatase activity in intact preparations, can reduce the intracellular production of biological active estrogen via the sulfatase pathway.
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PMID:In vitro effect of synthetic progestogens on estrone sulfatase activity in human breast carcinoma. 175 97

Estrone sulfatase is an important mechanism of local synthesis of biologically active estrogens in human breast cancer. The human placental microsome and breast carcinoma mitochondrial/microsomal estrone sulfatase activity were characterized and inhibition studies performed. The Km of the placental tissue enzyme was 6.83 microM, Vmax 0.015 nmol/min/mg, and for the breast carcinoma tissue Km was 8.91 microM and Vmax 0.022 nmol/min/mg. Danazol produced a significant inhibition of estrone sulfatase (20% with 50 microM danazol). No significant inhibition was seen in the presence of aminoglutethimide, rogletimide, tamoxifen, 4-hydroxyandrostenedione, stilboestrol, or any metabolites of danazol or tamoxifen. Studies with synthetic and naturally occurring steroids demonstrated that the presence of a sulfate group at the 3 position to be the most important factor in determining inhibition, and the most potent inhibitor was 5 alpha-androstene-3 beta,17 beta-diol-3-sulfate (Ki of 2.0 microM). The naturally occurring 3-sulfated steroids all demonstrated competitive inhibition. These studies could form the basis for the design of a potent estrone sulfatase inhibitor which would have potential therapeutic activity in the management of breast cancer.
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PMID:Inhibition of estrone sulfatase enzyme in human placenta and human breast carcinoma. 191 38

The growth of uterine leiomyoma is regulated not only by the estrogen levels in blood, but also by estrogen production in the tumor itself. In this study, we investigated both the estrone formation (estrone sulfatase activity) and the transformation from estrone to estrone sulfate (estrone sulfotransferase activity) in human leiomyoma tissue. We compared them with those in the myometrium and endometrial tissues overlying and opposite a uterine leiomyoma node. We also measured the tissue concentrations of estrone, estradiol and estrone sulfate. Estrone sulfatase activity in the uterine leiomyoma was 0.49 +/- 0.08 nmol/h/mg protein (Mean +/- SE), and was lower than that in the myometrial tissue (0.76 +/- 0.09). Moreover, the enzyme activity was higher in the endometrium overlying the leiomyoma node (2.62 +/- 0.29) than in the endometrium opposite to it (2.10 +/- 0.24). On the other hand, estrone sulfotransferase activity in the myoma (20.2 +/- 2.4 pmol/h/mg protein) was higher than in myometrial tissue (16.7 +/- 2.3). The concentrations of estrone and estradiol in leiomyoma tissue were lower than in the tissues surrounding the leiomyoma. The tissue concentration of estrone sulfate was higher in leiomyoma tissues. These results suggest that estrone sulfate is hydrolyzed mainly by estrone sulfatase in the endometrium and myometrium surrounding leiomyoma nodes and the estrone formed may affect the growth of leiomyoma.
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PMID:[Study on the local estrogen biosynthesis in human uterine leiomyoma]. 221 23

Estrone sulfatase activity was measured in normal and neoplastic endometrial tissues of human uterus. The tissue homogenates were incubated in air with [3H] estrone sulfate (E1-S, 20 microM) at 37 degrees C for 30 min. After the enzyme reaction was terminated with ethyl ether, the ethyl ether extract was purified by thin-layer chromatography. The apparent Km of sulfatase was 3.0 microM, and the maximum velocity was 14.7 nmol/h/mg protein. Estrone sulfatase activity in endometrial tissues was detected throughout the menstrual cycle with no significant change. Moreover, estrone sulfatase activity in endometrial cells was not stimulated by the addition of progestogen. The enzyme activity in cancer tissue was significantly higher than in normal tissue. Thus we concluded that this enzyme may play a role in regulating the estrogen action by sifting the intracellular equilibrium between free estrogens and estrogen sulfates. We also concluded that in the endometrial cancer tissue, sulfatase appears to act on local production of estrone.
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PMID:Estrone sulfatase activity in normal and neoplastic endometrial tissues of human uterus. 252 75

The activities of aromatase and estrone sulfatase which are important enzymes involved in the local production of estrogen in breast cancer tissue were measured to examine their availability in endocrine therapy and their clinical significance. The materials obtained were breast cancer tissue, noncancerous mammary gland and breast fat tissue from twenty eight patients with breast cancer, and mammary gland tissue from eight patients with benign breast disease. After centrifugation of homogenized tissue at 1000 X g, the supernatant of breast cancer tissue or mammary gland and the subnatant of breast fat tissue were used as enzyme sources. Aromatase activity was measured by 3H2O release assay using (1 beta-3H) androstenedione as the substrate, while estrone sulfatase activity was estimated from the conversion rate of (6,7-3H)estrone-3-sulfate to estrone. Aromatase activities were 25.1 +/- 12.4 (mean +/- S.D.) fmol/mg protein/h in twenty seven breast cancer tissue specimens, 11.0 +/- 6.1 fmol/mg protein/h in sixteen noncancerous mammary gland tissue specimens, 9.3 +/- 10.0 fmol/mg protein/h in twenty seven breast fat tissue specimens, and 7.7 +/- 5.5 fmol/mg protein/h in eight mammary gland tissue specimens from patients with benign breast disease. The aromatase activity in breast cancer tissue was significantly higher than that in noncancerous mammary gland, breast fat tissue and benign breast lesions (p less than 0.001). Estrone sulfatase activity was 4.0 +/- 3.5 nmol/mg protein/h in nineteen breast cancer tissue specimens, but was almost undetectable in eleven noncancerous mammary tissue specimens and eight benign breast lesions. These results suggest the relatively high local production of estrogen, mediated by aromatase or estrone sulfatase in breast cancer tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Local production of estrogen via aromatase and estrone sulfatase in breast cancer tissue]. 279 62

Two estrogen sulfatases, arylsulfatase C-estrone sulfatase (ASC-ES) and d-equilenin sulfatase (EqS) were demonstrated histochemically in the normal human female breast, in benign breast diseases and in infiltrating mammary ductal carcinomas to study their significance in the pathogenesis of epithelial proliferations. By hydrolyzing estrone sulfate, the amount of which in female blood is about ten times greater than that of estradiol or estrone, estrogen sulfatases can produce a high local concentration of estrogens. A simultaneous azo-coupling method for histochemical demonstration of ASC-ES is described in the present study; EqS was demonstrated by a previously described method. Estrogen sulfatases were not found in the normal female breast. Both estrogen sulfatases were found in epithelial cells in some examples of mastopathic disease and in fibroadenomas, while ASC-ES was found in periductal fibroblasts. In some cases of infiltrating ductal carcinomas, estrogen sulfatases were present in carcinoma cells. In most of these tumors ASC-ES activity was observed in fibroblasts around infiltrative cell cords. There was no correlation between the presence of estrogen sulfatases and of hormone receptors in carcinomas. It is concluded that estrogen sulfatases play no role in the early stages of benign or malignant epithelial proliferations. However, the induction of estrogen sulfatases may promote epithelial proliferation in some cases if estrogen receptors are present in epithelial cells.
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PMID:Histochemistry of estrogen sulfatases in human breast diseases. 286 35

Estrone sulfatase is a membrane-bound enzyme hydrolysing estrone sulfate. In normal and pathological tissues, estrone sulfatase is required for the conversion of estrone sulfate into physiologically active estrogens. In the hepatic cytosol of Guinea-pig, we have demonstrated the existence of a soluble inhibitor of uterine and hepatic microsomal estrone sulfatase. This inhibitor has approximatively a molecular weight of 7,600 and acts as a non-competitive inhibitor of estrone sulfatase. It seems to be a soluble intra-cellular effector of membrane-bound estrone sulfatase.
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PMID:[Demonstration of a cytosolic inhibitory of membrane estrone sulfatase activity in guinea pig liver]. 308 74


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