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

Recent results have shown that specific binding sites for luteinizing hormone-releasing hormone (LHRH) are present in biopsy samples of human endometrial cancer and in the human endometrial cancer cell lines Ishikawa and HEC-1A. The proliferation of these cell lines was retarded by LHRH analogs. The present study was undertaken to determine whether these endometrial tumor cells also produce LHRH or an LHRH-like peptide which could serve as natural ligand for the LHRH binding sites. Using a specific antibody, LHRH-immunoreactivity was detected in extracts of Ishikawa (426 +/- 84 fmol/10(6) cells) and HEC-1A (368 +/- 41 fmol/10(6) cells) cells. LHRH-like bioactivity of these samples was assessed in a rat pituitary cell culture system. The release of luteinizing hormone induced by endometrial cancer cell extracts corresponded to that obtained with comparable amounts of authentic LHRH. The expression of the mRNA for LHRH could be demonstrated by reverse transcriptase - polymerase chain reaction using specific primers according to the published sequence and by subsequent Southern blot analysis. The presence of immuno- and bioactive LHRH-like factors and the demonstration of expression of the mRNA for LHRH in two human endometrial cancer cell lines supports the concept of an autocrine regulatory system based on LHRH in endometrial cancer.
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PMID:Expression of luteinizing hormone releasing hormone and its mRNA in human endometrial cancer cell lines. 807 83

The involvement of altered c-jun activity in medroxyprogesterone acetate (MPA)-induced growth responses in human endometrial carcinoma cells is examined in this paper. Under conditions of MPA-induced growth inhibition, c-jun mRNA and protein levels are decreased in Ishikawa cells. This decrease is accompanied by an overall decrease in endogenous AP-1 activity in these cells. Only a transient decrease in c-jun mRNA level without any effect on endogenous AP-1 activity is seen in HEC-50 human endometrial carcinoma cells after MPA treatment. Increased expression and activity of c-jun was achieved in Ishikawa cells by transient transfection of Rous sarcoma virus (RSV)-c-jun alone or RSV-c-jun plus AP-1 binding sites (5x-4-beta-phorobol 12-myristate 13-acetate response element-thymidine kinase-chloramphenicol acetyltransferase), respectively. These treatments were accompanied by an increase in cell numbers due to MPA treatment in Ishikawa cells. In contrast, MPA treatment of mock-transfected, RSV-jun-B-transfected, or 5x-4 beta-phorbol 12-myristate 13-acetate response element-thymidine kinase-chloramphenicol acetyltransferase alone transfected Ishikawa cells resulted in the expected decrease in cell numbers. The data presented in this paper are consistent with the hypothesis that altered c-jun activity in a target cell can alter proliferative responsiveness to MPA and suggest that such a mechanism may be associated with resistance to hormonal manipulative therapies used in the treatment of both human breast and endometrial cancer.
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PMID:Enhanced c-jun activity alters responsiveness to medroxyprogesterone acetate in Ishikawa human endometrial carcinoma cells. 814 69

Although specific binding sites for LH-releasing hormone (LHRH) and its analogs have been demonstrated in biopsy samples of human endometrial cancer, their biological significance remains obscure. In this study we evaluated whether binding sites for LHRH are also present in the human endometrial cancer cell lines HEC-1A and Ishikawa and if such sites could mediate antiproliferative effects of LHRH analogs. Using [125I,D-Trp6]LHRH as a ligand, a high affinity/low capacity binding site was detected in both lines: HEC-1A line, dissociation constant (Kd)1 = 5.7 x 10(-9) mol/L, binding capacity (Bmax)1 = 78 fmol/10(6) cells; Ishikawa line, Kd1 = 4.2 x 10(-9) mol/L, Bmax1 = 29 fmol/10(6) cells. In addition, a second class of low affinity/high capacity binding sites for LHRH was demonstrated (HEC-1A line, Kd2 = 1.4 x 10(-6) mol/L, Bmax2 = 21 pmol/10(6) cells; Ishikawa, Kd2 = 4 x 10(-6) mol/L, Bmax2 = 32 pmol/10(6) cells). In the presence of 10(-5) mol/L agonist [D-Trp6]LHRH (triptorelin), the proliferation of HEC-1A and Ishikawa cell lines was significantly reduced to 76 +/- 2% and 88 +/- 4% of controls, respectively, after 24 h and to 64 +/- 2% and 62 +/- 2%, respectively, after 6 days. Dose-response experiments showed that lower concentrations (10(-9) mol/L) of the agonist decreased the proliferation to 80 +/- 1% for the HEC-1A line and 71 +/- 2% of controls for the Ishikawa line after 6 days. Antiproliferative effects are enhanced by increasing the doses of triptorelin and were maximal in this series of experiments at 10(-5) mol/L, the proliferation in the HEC-1A line being 62 +/- 1% and in the Ishikawa line 52 +/- 2% of controls, respectively. Similar time- and dose-dependent antiproliferative effects were obtained in both cell lines with the LHRH antagonist SB-75 (cetrorelix). These data suggest that LHRH analogs can directly inhibit the proliferation of human endometrial cancer cells in vitro. This direct action could be mediated through the high affinity LHRH binding sites.
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PMID:High affinity binding and direct antiproliferative effects of luteinizing hormone-releasing hormone analogs in human endometrial cancer cell lines. 826 28

Sex steroid hormone dependent cell proliferation and inducing growth factors of endometrial carcinoma cells were investigated using in vitro culture systems. The cell proliferation of Ishikawa cells derived from well-differentiated endometrial adenocarcinoma which possess both estrogen and progesterone receptors were stimulated by either estradiol added to culture media or EGF and TGF-alpha acting through EGF receptors. These stimulatory effects of TGF-alpha were antagonized by the anti TGF-alpha and EGF-receptor antibodies. The cell proliferations of other endometrial cancer cells were also inhibited by those antibodies. All endometrial cancer cells secrete TGF-alpha into their culture media measured by TGF-alpha ELISA methods. The expression of TGF-alpha mRNA and secretion of TGF-alpha of Ishikawa cells were induced by estradiol but not of hormone independent HEC-50 cells. Thus suggest that estradiol dependent growth factor should be TGF-alpha in human endometrial carcinoma cells.
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PMID:[In vitro study for hormones and growth factors dependent cell proliferation of endometrial adenocarcinoma cells]. 829 14

We have previously documented the responsiveness of a cell line of human ovarian epithelial carcinoma (Bowman Gray 1) heterotransplanted in nude mice to treatment with the GnRH agonist Lupron-SR. In this study we used another human ovarian epithelial carcinoma cell line, OVCAR-3, and the human endometrial carcinoma cell line HEC-1A. After a latent period, OVCAR-3 tumors showed significant inhibition of growth on Days 17, 21, and 24 (P < 0.03) compared to controls. The effect was transient and did not persist beyond Day 24. HEC-1A tumors showed no inhibition of growth. Radioreceptor assay studies utilizing native radiolabeled GnRH and [D-Lys6]-GnRH revealed no specific GnRH receptors in any of the tumor samples (BG-1, OVCAR-3, HEC-1A, University of Nebraska cell line, and two fresh human ovarian epithelial tumor samples) compared to male rat anterior pituitary cells. Binding studies and the latency and transience of effect would suggest that the mechanism of action in this animal model may be indirect. This activity may be via altered circulating steroids, gonadotropins, cell-cycle regulatory events, or some other as-yet-undefined action related to GnRH agonist administration or indirectly via effects of the metabolic products of degraded GnRH agonist such as D-amino acids, which are incorporated into the cells by constitutive or adsorptive pinocytosis. This study confirms latency and transience of effect of GnRH agonist therapy on an in vivo model of ovarian cancer.
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PMID:GnRH agonist therapy in human ovarian epithelial carcinoma (OVCAR-3) heterotransplanted in the nude mouse is characterized by latency and transience. 830 97

Paraffin-embedded materials obtained from 117 cases of endometrial hyperplasia and 84 cases of carcinoma were used for measurement of both ki-ras and p53 gene mutation and aromatase (ARO) and TGF-alpha immunostaining. The overall incidence of ki-ras mutations in the hyperplasia specimens (16%) was similar to the incidence detected in carcinomas (18%). None of 117 endometrial hyperplasias were found to have mutations in the p53 gene, whereas mutations were seen in 3 (13.3%) endometrial carcinomas. The intensity of both ARO and TGF-alpha immunostaining was increased in glands of both hyperplasia and carcinoma, and also in the interstitium of carcinoma. The positive sites of both ARO and TGF-alpha were almost the same, with an incidence below 40% in both hyperplasias and carcinomas. The cultured cells of endometrial carcinoma showed aromatase activity below MCF-7 cells, because testosterone was converted to estradiol (E2). TGF-alpha induced cell growth with at an optimal concentration. In HEC-59 cells, TGF-alpha increased both ARO-activity and mRNA. Some promoters on ARO-exon 1 in HEC-59 cells were different from those in BeWo cells. Progesterone inhibited the E2-induced excretion of pre TGF-alpha in endometrial carcinoma cells. These findings suggest that endometrial hyperplasia can be a premalignant condition of carcinoma, and can be initiated by both ki-ras codon 12 mutation and abnormal activity of ARO induced by TGF-alpha. In addition, HEC-59 cells may possess autocrine/paracrine properties involving ARO, E2 and TGF-alpha.
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PMID:[Aromatase activities of endometrial carcinomas and both basic and clinical analyses of endometrial hyperplasia as a premalignant disease]. 837 Oct 7

We focused on the glycosphingolipids as one of the various biological phenotypes on the cell membrane of malignant tumor cells. The composition of three glycosphingolipids in seven human cell lines, derived from gynecological malignant tumors, was analyzed biochemically and immunochemically. Among the seven human cell lines, lactosylceramide sulfate was characteristically detected in these endometrial cancer cell lines, HEC-108, SNG-II, and SNG-M. In contrast, no sulfoglycolipids were found in the other malignant cell lines. HEC-108, which forms a moderately differentiated endometrial adenocarcinoma in nude mice, had a much higher ratio of lactosylceramide sulfate/GM3 than SNG-II and SNG-M cell lines, both of which grow as poorly differentiated endometrial adenocarcinoma in nude mice. TLC-immunostaining revealed that the sialyl type I carbohydrate chain with polysialyl groups was preferentially contained in the two sarcoma-derived cell lines and not in the five carcinoma-derived ones, while the type I carbohydrate chain was detected in all lines examined. Furthermore, the carcinoma cell lines were found to express A,B,H,Le(a),Le(b),Le(x) and Le(y) glycolipids, whereas the sarcoma cell lines scarcely expressed them. These results suggest that the expression of lactosylceramide sulfate is one of the biological characteristics of the three endometrial cancer cell lines, and the fucosylation to terminal residues of the type I and type II carbohydrate chains might be reduced in uterine sarcoma- and ovarian sarcoma-derived cell lines.
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PMID:[Glycosphingolipids of human gynecological malignant cell lines in vitro]. 842 47

Aromatase, estrone (E1) sulfatase and E1 sulfotransferase activities were examined in endometrium and endometrial cancer tissue preparations. Aromatase and E1 sulfatase activities in endometrial cancer tissues were found to be significantly higher than in normal endometrial tissues. However, E1 sulfotransferase activity did not differ between benign and malignant tissue. We also examined the effect of testosterone (T) on aromatase activity and tritiated thymidine uptake (DNA synthesis) in various cultured cervical or corpus endometrial cancer cell lines (OMC-4, HHUA, Ishikawa, HEC-59). The results demonstrated that only the HEC-59 cell line had high aromatase activity and increased its DNA synthesis in response to T. This increase of DNA synthesis by T was not suppressed by simultaneous addition of cyproterone acetate, but was by tamoxifen. These data suggest that in situ estrogen production in endometrial cancer tissue is biologically important and that aromatase in cancer cells may contribute partially to cell proliferation if androgen substrate is provided.
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PMID:Estrogen productivity of endometrium and endometrial cancer tissue; influence of aromatase on proliferation of endometrial cancer cells. 847 61

Repair of human endometrium after menstruation and preparation of the endometrium for implantation involves profound angiogenic changes. Vascular endothelial cell growth factor (VEGF) is a recently identified growth factor with significant angiogenic properties. Four species of mRNA encoding VEGFs were identified in human endometrium and myometrium. All species were present throughout the menstrual cycle. Two species, VEGF165 and VEGF121, were present in peripheral leukocytes, indicating tissue-specific splicing of the two other VEGF transcripts. In situ hybridization of mRNA encoding VEGF was not restricted to vascular smooth muscle but was present in epithelial and stromal cells of endometrium throughout the cycle, and the distribution changed during the course of the cycle. All four species of VEGF were expressed by the endometrial carcinoma cell lines Ishikawa, HEC 1-A, and HEC 1-B. Estradiol increased steady-state levels of mRNA encoding VEGF in a dose- and time-dependent manner in HEC 1-A cells. Conditioned medium from these cells possessed angiogenic activity that was depleted by passage through a heparin affinity column. None of the cell lines demonstrated mRNA for acidic or basic fibroblast growth factor (FGF), despite previous reports of the identification of immunoreactive basic FGF in HEC 1-A and HEC 1-B cells. These findings show that VEGFs, not FGFs, are the principal angiogenic growth factors secreted by these cells and that human endometrium expresses a secreted angiogenic growth factor whose site of expression changes during the menstrual cycle.
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PMID:Identification and localization of alternately spliced mRNAs for vascular endothelial growth factor in human uterus and estrogen regulation in endometrial carcinoma cell lines. 848 75

In England, pharmacologists and a biochemist at the University of Liverpool used an established human endometrial cancer cell line (HEC-1A) and human endometrial tissue in vitro to confirm that HEC-1A and tissue metabolize oral contraceptive (OC) steroids. They used on-line radiometric high-performance liquid chromatography to analyze metabolic activity. Surgeons obtained the endometrial tissue from women undergoing dilatation and curettage or hysterectomy at the Royal Liverpool University Hospital. Earlier research showed that HEC-1A cells interconvert estrone (E1) and 17 beta-estradiol (E2), with E2 predominating in the equilibrium. In this in vitro study, healthy endometrial tissue extensively changed E2 to E1, while malignant tissue caused this conversion to a much lesser extent. The healthy endometrial tissue of some patients formed sulphate conjugates. Both HEC-1A and endometrial tissue hydrolyzed E1 3-sulphate. They did not bring about phase I metabolism when ethinyl estradiol (EE2) was the substrate. Yet, incubation with healthy tissue from some women did lead to conversion of the presumed 3-sulphate conjugate. Incubation with HEC-1A cells completely removed the acetyl group from norgestimate, resulting in mainly norgestrel oxime (55.1% of metabolites) within 24 hours. It also resulted in some norgestrel (16.3%). Incubation with endometrial tissue also brought about complete metabolism of norgestimate within 24 hours. The tissue from different women brought about qualitative and quantitative differences. HEC-1A and endometrial tissue did not metabolize much of 3-ketodesogestrel (3-KDG). In fact, the major metabolite formed by HEC-1A was 3 alpha-hydroxydesogestrel, which made up 3.3% of total added radiolabeled steroid. Healthy endometrial tissue did not produce any phase I metabolites of 3-ketodesogestrel, while tumor tissue may have produced a small amount of radiometabolites. These findings indicate that the endometrium does metabolize the OC EE2, 3-KDG, and norgestimate.
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PMID:Metabolism of the oral contraceptive steroids ethynylestradiol, norgestimate and 3-ketodesogestrel by a human endometrial cancer cell line (HEC-1A) and endometrial tissue in vitro. 849 48


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