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Query: UMLS:C0476089 (endometrial cancer)
 11,379 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sedimentation coefficients of cytoplasmic estradiol and progesterone receptors of human proliferative endometrium and endometrial carcinoma were determined by sucrose gradient centrifugation. In the absence of KCl, receptors from proliferative endometrium sedimented as single bands in the 8 S region and in the presence of 0.3M KCl in the 4 S region of the gradients. Receptors from endometrial carcinoma sedimented in several bands (between 3 and 9 S). When chromatographed on agarose gel comumns, the receptors (from both normal and neoplastic tissue) showed different molecular weights in the presence and absence of KCl (approximately 40,000 and 120,000, respectively). Elution profiles from agarose gel and ion exchange columns, as well as electrophoretic patterns from isoelectric focusing, revealed a similarity between biochemical properties of the receptors from endometrial carcinoma and proliferative endometrium. While the concentration of binding sites for estradiol and progesterone in normal endometrium depended on the day of the cycle, in endometrial carcinoma it depended on the degree of differentiation of the tumor. The binding of estradiol was highest at the beginning of the proliferative phase and declined continuously towards the 14th day of the cycle. In contrast, the concentration of progesterone binding sites was relatively low throughout the proliferative phase. In endometrial carcinoma low binding of estradiol was obtained in well differentiated tumors and high binding (as high as in proliferative endometrium) in undifferentiated tumors. For progesterone the contrary was the case. There was no difference in pH sensitivity between cytoplasmic receptors from normal and neoplastic tissue, optimal binding occurring at pH 7. Dissociation constants (Kd) for estradiol and progesterone depended on the degree of tumor differentiation. Kd values increased for E2 and decreased for P with increasing differentiation of the tumor. Competition studies with various unlabeled steroids revealed no significant difference between the specificity of the receptors from proliverative and neoplastic endometrium.
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PMID:Characterization and comparison of receptors for 17 beta-estradiol and progesterone in human proliferative endometrium and endometrial carcinoma. 23 81

In the study reported here, non-histamine chromosomal proteins from proliferative and secretory human endometrium, and from undifferentiated endometrial carcinoma have been separated into more than 750 protein components, using a new preparative and highly sensitive analytical method. The following experimental procedure was applied: 1. Dissociation of chromatin under different conditions (variable parameters: ion strength, dissociation agents, shearing, pH), 2. cation exchange chromatography over Bio Rex, 3. preparative fractionation of those non-histamine chromosomal proteins which are not adsorbed on Bio Rex 70 in a Valmet-electrofocusing apparatus, 4. micro-electrophoresis of the focused proteins in microgels containing a continous gradient of polyacrylamide, 5. two-dimensional electrophoresis of the strongly basic chromosomal proteins. There are qualitative differences with respect to the components of this class of proteins between proliferative and secretory endometrium and endometrial carcinoma. The relevance of these results to the control of gene activity is discussed.
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PMID:Comparison of acidic and basic chromosomal proteins from normal human endometrium and undifferentiated endometrial carcinoma by isoelectric focussing and microgel-electrophoresis. 45 87

The effects of trans-4-hydroxytamoxifen (OHTam) on proliferation of cells of the Ishikawa human endometrial adenocarcinoma line were studied under serum-free, phenol red-free conditions and compared to those of estradiol. The addition of OHTam (1 microM) to basal medium (BM), consisting of equal parts of Dulbecco's modified Eagle's medium and Ham's F-12 with additional glutamine and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, resulted in significant increases in cell numbers relative to controls. These effects were even greater than those obtained with estradiol (10 nM-1 microM) or 1% charcoal-treated fetal bovine serum (ctFBS). Addition of 1% ctFBS to BM containing 1 microM OHTam further increased cell numbers whereas addition of estradiol (10 nM) did not do so. The stimulation of growth was positively correlated with OHTam concentrations in the range of 10 nM to 1 microM. Dissociation of estradiol and OHTam proliferative effects was observed in a variant of Ishikawa cells in which estradiol did not increase proliferation while OHTam had a strong stimulatory effect. The growth-promoting effects of OHTam were also observed in BM containing 5% or 15% ctFBS. In contrast, in parallel experiments in which BM was replaced by minimal essential medium (Eagle's) with Earle's salts, OHTam (1 microM) did not stimulate proliferation under these conditions and acted as an antiestrogen, inhibiting the proliferative effects of estradiol. These results illustrate marked effects of medium composition on proliferation and antiestrogenic actions of OHTam. Alkaline phosphatase activity was strongly stimulated by estradiol (10 nM) but only very weakly affected by OHTam (1 microM); at these concentrations, OHTam inhibited the effect of estradiol, both in serum-free BM and in minimal essential medium plus 15% ctFBS, demonstrating dissociation in its actions on proliferation and on enzymatic activity. These findings suggest that OHTam may stimulate the proliferation of particular clones of endometrial cancer cells in human tumors. They also suggest that OHTam can exert effects not mediated by the estrogen receptor system, or form OHTam-estrogen receptor agonistic complexes unlike those resulting from estradiol-estrogen receptor interactions. Clearly, Ishikawa cells provide a useful model to investigate mechanisms of action of antiestrogens.
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PMID:Stimulatory effects of 4-hydroxytamoxifen on proliferation of human endometrial adenocarcinoma cells (Ishikawa line). 270 24