Search results for " Progesterone"
showing 10 items of 83 documents
Synthesis of a New Disulfide Affinity Adsorbent for Purification of Human Uterine Progesterone Receptor
2005
For purification of the human uterine progesterone receptor, an affinity adsorbent was synthesized in which the specific ligand (16 alpha-ethyl-3-oxo-19nor-androst-4-ene 17 beta-carboxylic acid) was bound to derivatized celulose using a disulfide-group-containing spacer. The purified receptor protein, isolated by reductive cleavage of the disulfide bond, bound the synthetic gestagen R5020 with high affinity (Kd 12.2 nmol/l). The affinity gel was highly efficient. A 24000-fold purification of progesterone receptor with a recovery of 40% could be achieved in a single step within 6 h. By means of dodecyl sulphate/polyacrylamide gel electrophoresis two main polypeptides with molecular weights o…
Breast cancer genome-wide association studies: there is strength in numbers.
2012
Breast cancer (BC) is a heterogeneous disease that exhibits familial aggregation. Family linkage studies have identified high-penetrance genes, BRCA1, BRCA2, PTEN and TP53, that are responsible for inherited BC syndromes. Moreover, a combination of family-based and population-based approaches indicated that genes involved in DNA repair, such as CHEK2, ATM, BRIP and PALB2, are associated with moderate risk. Therefore, all of these known genes account for only 25% of the familial aggregation cases. Recently, genome wide association studies (GWAS) in BC revealed single nucleotide polymorphisms (SNPs) in five novel genes associated to susceptibility: TNRC9, FGFR2, MAP3K1, H19 and lymphocyte-spe…
Associations of common breast cancer susceptibility alleles with risk of breast cancer subtypes in BRCA1 and BRCA2 mutation carriers
2014
Introduction More than 70 common alleles are known to be involved in breast cancer (BC) susceptibility, and several exhibit significant heterogeneity in their associations with different BC subtypes. Although there are differences in the association patterns between BRCA1 and BRCA2 mutation carriers and the general population for several loci, no study has comprehensively evaluated the associations of all known BC susceptibility alleles with risk of BC subtypes in BRCA1 and BRCA2 carriers. Methods We used data from 15,252 BRCA1 and 8,211 BRCA2 carriers to analyze the associations between approximately 200,000 genetic variants on the iCOGS array and risk of BC subtypes defined by estrogen re…
Does tamoxifen change oestrogen and progesterone receptor expression in the endometrium and breast?
2000
We studied the expression of oestrogen and progesterone receptors (ER, PR) in postmenopausal women receiving tamoxifen for breast cancer. In addition the literature addressing the question of ER and PR expression in breast tissue during treatment with tamoxifen was reviewed. We demonstrated consistent expression of ER and PR in endometria from patients receiving tamoxifen, with a trend towards a higher proportion of receptor positive specimens during tamoxifen. In breast cancer tissue, the ER content seemed to be reduced following tamoxifen treatment. After short time exposure to tamoxifen, the PR appeared to be increased, longer treatment caused the PR to go down to pretreatment levels or …
3H-estradiol and3H-R5020 binding in cytosols of normal and neoplastic human ovarian tissue
1983
High-affinity cytoplasmic estrogen and progesterone receptors in normal and abnormal ovarian tissues were studied. Estradiol receptor was detectable in 65% and progesterone receptor in 36% of the malignant tumors; 39% of all malignant ovarian tissues were estradiol- as well as progesterone-receptor-positive. Tumors were said to be receptor-positive when the receptors bound greater than 5 fM steroid/mg cytosol protein. No correlations were found between receptor status and histopathological diagnosis. In normal ovarian tissues collected at various phases of the menstrual cycle no changes in [3H]-estradiol and [3H]-R5020 binding could be detected. Analysis of the receptor concentration for bo…
Role of the progesterone receptor for paclitaxel resistance in primary breast cancer
2007
Paclitaxel plays an important role in the treatment of primary breast cancer. However, a substantial proportion of patients treated with paclitaxel does not appear to derive any benefit from this therapy. We performed a prospective study using tumour cells isolated from 50 primary breast carcinomas. Sensitivity of primary tumour cells to paclitaxel was determined in a clinically relevant range of concentrations (0.85-27.2 microg ml(-1) paclitaxel) using an ATP assay. Chemosensitivity data were used to study a possible association with immunohistochemically determined oestrogen and progesterone receptor (ER and PR) status, as well as histopathological parameters. Progesterone receptor (PR) m…
Quantitative monoclonal antibody determination of estrogen and progesterone receptors in human breast cancer: correlation with the radioligand method.
1994
To assess the possibility of substituting our routine method (dextran-coated charcoal, DCC) of determining estrogen (ER) and progesterone receptors (PR) for an enzyme immunoassay technique (EIA), we compared the two methods for determination of the two types of receptor in breast cancer specimens. In terms of sample positivity or negativity, the two techniques agreed in 76 of the 82 samples analyzed for ER (92.7%; p0.001), and in 65 out of 75 samples assayed for PR (86.6%; p0.001). Quantitative analysis of the data showed a significant correlation between DCC and EIA for both ER (r = 0.84; p0.0001) and PR (r = 0.77; p0.0001). The results suggest the usefulness of EIA in substituting DCC, al…
High-performance and ion-exchange chromatography and chromatofocusing of the human uterine progesterone receptor: its application to the identificati…
1984
Two independent lines of evidence were used to identify the human uterine progesterone receptor. First, three differently tritiated progestogens (Org 2058, R 5020, progesterone) were used for reversible labelling of the receptor. Secondly, the highly potent affinity label 21-[3H]dehydro Org 2058 was used to label covalently the steroid-specific binding site of the receptor. The labelled cytosols were chromatographed on a Mono Q high-performance anion-exchange column in the absence or presence of a high molar excess of the respective unlabelled competitor steroids. In the case of 21-[3H]dehydro Org 2058, Org 2058 was used as the unlabelled competitor. After elution with a NaCl gradient, the …
An automatic multidimensional chromatography system for purification of human uterine progesterone receptor and induction of polyclonal antibodies.
1986
Abstract This paper reports on the synthesis of Org2058-bonded microparticulate silicas and their use in affinity chromatography as the first step for the purification of human progesterone receptor. The development of microprocessor-controlled instruments allows all the various steps to be performed automatically. The various steps used for the purification of human progesterone receptor were carried out with the FPLC system: (1) affinity chromatography, (2) desalting of eluate on Sephadex G-25, (3) anion-exchange chromatography using a Mono Q column. With this procedure the receptor was purified approx. 10,000-fold within 24 h. The yield of receptor was generally 85–95%. Investigations wi…
A comparison of cytoplasmic and nuclear estradiol and progesterone receptors in human fallopian tube and endometrial tissue
1981
Quantitative and qualitative aspects of the in vitro binding of 3 H-estradiol and 3 H-progesterone to receptor components from human endometrium and fallopian tube cytoplasmic and nuclear fractions were studied. The steroid binding macromolecules formed in vitro could be extracted from nuclei by 0.4M KCl and detected by glycerol gradient centrifugation. Both estradiol- and progesterone-binding compounds formed only one peak (under high ionic strength conditions) with a sedimentation coefficient of about 4-5S. The number of cytoplasmic and nuclear binding sites for both estradiol and R5020 varied dramatically throughout the menstrual cycle: the estradiol and progesterone receptor concentrati…