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
Query: UMLS:C0476089 (
endometrial cancer
)
11,379
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The insulin-like growth factors (IGFs) I and II are present in extracellular fluids associated with specific binding proteins (IGFBPs) that can modify their biologic actions. These studies were undertaken to determine which forms of IGFBP are secreted by
endometrial carcinoma
(HEC-1B) and breast carcinoma (MDA-231) cells, to characterize variables that control IGFBP secretion, and to study the effect of IGFBP-1 and IGFBP-2 on IGF-I stimulated cell proliferation. Secreted IGFBPs were identified by ligand blotting and IGFBP-1 was quantified using a specific radioimmunoassay (RIA). MDA-231 cell conditioned media (CM) contained four (43,000, 39,000, 30,000 and 24,000 Mr) forms of IGFBP, and HEC-1B cell CM contained three forms (39,000, 34,000 and 30,000 Mr). Immunoblotting showed that the 30,000 Mr form secreted by both cell types was IGFBP-1. Likewise the 34,000 Mr band in HEC-1B media reacted with IGFBP-2 antiserum and the 39,000 and 43,000 Mr bands reacted with IGFBP-3 antiserum. IGF-I stimulated the secretion of IGFBP-3 from both cell types and IGFBP-2 from HEC-1B cells but either decreased or caused no change in secretion of IGFBP-1 and a 24,000 Mr form. In contrast, insulin inhibited the secretion of IGFBP-1 but increased the secretion of the 24,000 Mr form. Compounds that elevate intracellular
cAMP
levels increased the secretion of IGFBP-3, IGFBP-1, and the 24,000 Mr form from both MDA-231 and HEC-1B cells. When sparse cultures of MDA-231 cells were used, addition of IGF-I caused a 24% increase in cell number after 48 hr. This mitogenic response was enhanced by the presence of recombinant human IGFBP-1 (45% increase in cell number, P less than 0.001). Bovine IGFBP-2 did not potentiate IGF-I stimulated cell proliferation. These findings show that two tumor cell lines secrete distinct forms of IGFBPs and that there is differential regulation of IGFBP secretion. At least one form secreted by both tumors may act as a positive autocrine modulator of IGF-I's growth stimulating actions.
...
PMID:Secretion and biological actions of insulin-like growth factor binding proteins in two human tumor-derived cell lines in vitro. 171 44
By statistical study on 135 patients with
endometrial carcinoma
, it is clarified that the most effective prognostic factor of the cancer is the histological grading. Well differentiated type is best prognostic and possesses hormone receptors. Application of cell culture is one of the most suitable choices in the study of hormone and human
endometrial carcinoma
. Present paper is to show usefulness of in vitro study by taking example of the above theme. 1) Binding ability of
endometrial carcinoma
cells to estrogen: Being explained by Gurpide et al. by using HEC-1 cells, the ability is under control of cGMP and
cAMP
ratio. 2) Responses to estrogen: DNA polymerase alfa of Ishikawa cells which possesses both estrogen and progesterone receptors (ER, PR) is stimulated first showing peak at 18 hours and alkaline phosphatase (ALP) is at 72 hours by E(2)10(-8)M, which is antagonized by OH-tamoxifen. PR level is also enhanced at its maximum after 3 day E2 treatment, and is analyzed by immunocytochemistry with PR mono-clonal antibody as well as biochemical assay. Gorski and Greene's theory that steroid receptor is localized in nuclei is confirmed in
endometrial carcinoma
. Growth of Ishikawa cells is apparently enhanced in the aspects of shortened cell cycle and unlimited saturation density. 3) Responses to progestogen: Nucleic acid syntheses of HEC-1 are immediately suppressed by progesterone (P) 2.5 microg or more. Electron microscopic findings show appearances of Golgi apparatus and lysosomal granules. Growth suppression is observed in the cell lines regardless of PR positivity. ALP activity of PR-negative HEC-50 cells
...
PMID:[Cell culture--its application in the study of hormone and endometrial carcinoma and feed-back to clinical medicine]. 315 Aug 47
Addition of cGMP to cytosol of human endometrium or to cells of the
endometrial cancer
line HEC-1 produced severalfold increases in specific estrogen binding (EB) levels. This effect was maximal with 1 microM cGMP in the presence of 0.1 mM isobutylmethylxanthine (a phosphodiesterase inhibitor) during incubations with [3H]estradiol. In contrast,
cAMP
decreased EB levels under similar conditions. The effects of cyclic nucleotides on EB levels were complete in less than 15 min in the presence of Mg2+, Mn2+, or Ca2+. The EB sites generated by the addition of cGMP during labeling of cytosol with 10 nM [3H]estradiol were found to sediment in the 8S and 4S regions of low-salt glycerol gradients. No changes in EB levels were observed when cyclic nucleotides were added to cytosol depleted of ATP by preincubation at 4 degrees C for 3 hr, but responsiveness was restored by addition of exogenous ATP. The ATP requirement and the pattern of dependence of cyclic nucleotide actions on divalent cation concentrations suggest that cGMP and
cAMP
effects may be mediated by kinases and may involve phosphorylations. Another possibility is that the cyclic nucleotides interact allosterically with the binder in the presence of ATP. Addition of sodium molybdate, ATP, and GTP to homogenates of endometrial tissue or HEC-1 cells produces increases in EB levels similar to those obtained by the addition of cGMP. However, these compounds are much less active when added to cytoplasm or cytosol. On the basis of these and other observations, it is hypothesized that molybdate, ATP, and GTP affect EB levels primarily by increasing cGMP concentrations through processes involving a plasma membrane-bound guanylate cyclase.
...
PMID:Rapid changes in specific estrogen binding elicited by cGMP or cAMP in cytosol from human endometrial cells. 630 87
Recent experimental results from our laboratories revealed the following facts: Addition of GMP to homogenates or cytosol prepared from endometrial tissue or cultured endometrial adenocarcinoma cells during the assay for specific estrogen binders markedly increases specific binding levels. The effect is completed in about 15 min at 4 C (Fleming et al, 1983).
Cyclic AMP
has the opposite effect and in many cases lowers the number of binding sites to undetectable levels. ATP, a nucleotide that stimulates a particulate form of guanylate cyclase, Na2MoO4, a compound that can elevate cGMP levels (Fleming and Blumenthal, unpublished) and GTP, a metabolic precursor of cGMP, increase specific estradiol binding in the presence of plasma membranes and soluble factors.
Cyclic AMP
reduces the levels of estrogen binding when added to cell homogenates or to cytosol and counteracts the effects of cGMP, MoO4, ATP and GTP. ATP is required for the expression of cGMP and
cAMP
effects on estradiol binding. It is therefore likely that phosphorylations are involved in the generation and inactivation of estrogen binding sites. Divalent cation requirements for these effects also suggest participation of protein kinases in these processes. The reported effects of nucleotides and molybdate have been observed in specimens of histologically normal endometrium, in specimens of
endometrial carcinoma
, in two endometrial adenocarcinoma cell lines, HEC-1 and HEC-50 (Suzuki et al, 1980), and in two breast cancer cell lines, CG-5, a variant of MCF-7 obtained in Iacobelli's laboratory (Natoli et al, 1983), and in T47D) (Fleming et al, in press) Rapid changes in the levels of estrogen binding capacity observed in endometrial cells in culture can be associated with changes in cGMP/
cAMP
ratios shown, to vary during the cell cycle. Although it has not yet been demonstrated that cGMP-induced increases in specific estrogen binding can enhance responses to available estrogens, such possibility is of potential importance. Reduction of estrogen receptor levels in patients with cancers of estrogen sensitive tissues may inhibit tumor growth promoted by endogenous estrogen. Cho-Chung et al have recently reported that cholera toxin causes a reduction in estrogen receptor levels and arrests hormone dependent growth of DMBA-induced mammary carcinoma in rats (Cho-Chung et al, 1983). They postulated that the effect of cholera toxin is mediated by a
cAMP
effect on the estrogen receptor, an hypothesis supported by the observation that only tumors containing receptor responded to treatment. Conversely, cGMP-induced increases in specific estrogen binders may be useful in promoting a response of tumors to estr
...
PMID:Regulation of estrogen receptor levels in endometrial cancer cells. 670 55
The present study was undertaken to determine whether
endometrial cancer
cell line HEC-1-A differ from nontransformed cells, in that the
cAMP
and protein kinase C pathways may enhance IGF-I effects in mitogenesis by acting at the G1 phase of the cell cycle instead of G0. Immunofluorescence staining of HEC-1-A cells using the proliferating cell nuclear antigen (PCNA) monoclonal antibody and flow cytometric analysis determined that HEC-1-A cells do not enter the G0 phase of the cell cycle when incubated in a serum-free medium. Approximately 51% of the cells were in G1, 12% were in S and 37% in G2 phase of the cell cycle prior to treatment. Forskolin and phorbol-12-myristate 13-acetate (PMA) were used to stimulate
cAMP
production and protein kinase C activity, respectively. IGF-I, forskolin and PMA each increased (P < 0.01) [3H]-thymidine incorporation in a dose and time dependent manner. The interaction of forskolin and PMA with IGF-I was then determined. Cells preincubated with forskolin or PMA followed by incubation with IFG-I incorporated significantly more (P < 0.01) [3H]-thymidine into DNA than controls or any treatment alone. It is concluded that forskolin and, to a lesser extent, PMA exert their effect at the G1 phase of the cycle to enhance IGF-I effects in cell proliferation.
...
PMID:cAMP and PMA enhance the effects of IGF-I in the proliferation of endometrial adenocarcinoma cell line HEC-1-A by acting at the G1 phase of the cell cycle. 773 22
A plasminogen activator (PA) system is involved in ovulation, implantation, tumor invasion and metastasis. In order to clarify the regulation of this PA system in endometrial cells, we examined which agent affecting cellular function altered tissue-type plasminogen activator (t-PA) secretion by
endometrial carcinoma
cell line (KLE cells) in vitro. Triiodothyronine, retinoic acid, insulin, 8-bromo-
cAMP
, PDGF, IGF-I, basic FGF or TNF-alpha did not alter t-PA secretion while the activator of protein kinase C, phorbol myristate acetate (PMA) stimulated t-PA secretion in a dose-dependent fashion (10(-10)-10(-8) M). The time required to give a statistically significant increase in t-PA over control was 3 hours, and the maximal increase was seen after 24 hours of exposure. Another active phorbol ester, PDD also stimulated t-PA secretion while inactive forms of phorbol ester, 4 alpha-PDD and phorbol did not alter it. Cholera toxin or 8-bromo-
cAMP
did not affect t-PA secretion, but enhanced PMA-stimulated t-PA secretion. Cycloheximide and actinomycin D completely abolished PMA-stimulated t-PA secretion. These results suggest that (1) t-PA secretion in the
endometrial carcinoma
cell is modulated by a protein kinase C system, (2) This effect is through new RNA production and protein synthesis. (3) There is a complicated relationship between protein the kinase C and protein kinase A system as to the regulation of t-PA secretion. This would be a suitable model to clarify the PA system in endometrial cells.
...
PMID:[Effect of phorbol ester on tissue-type plasminogen activator (t-PA) secretion in endometrial carcinoma cell line in vitro]. 812 84
To understand the molecular mechanisms underlying the regulation of hepatocyte growth factor (HGF) gene expression and to define the DNA sequences essential for its cell-type specific and inducible expression, we have isolated and characterized the 5'-flanking region of the HGF gene. A genomic clone containing 2.8 kilobases of the 5'-flanking region of the HGF gene has been isolated from a mouse liver genomic library. Sequence analysis showed that the promoter region of the mouse HGF gene contains a noncanonical TATA box (ATAAA). Further analysis of the 5'-flanking region revealed a number of putative regulatory elements, such as four interleukin-6 response elements (IL-6 RE), two potential binding sites for NF-IL6, a TGF-beta inhibitory element (TIE), a
cAMP
response element (CRE), two estrogen response elements (ERE) including one located in the first intron, a potential vitamin D response element (VDRE) which overlaps a chicken ovalbumin upstream promoter (COUP) transcription factor binding element, two liver-specific transcription factor (C/EBP) binding sites, and a B cell- and macrophage-specific transcriptional factor binding site (PU.1/ETS). To determine the location of sites that may be critical for the function of the HGF promoter, we constructed a series of chimeric genes containing variable regions of the 5'-flanking sequence of HGF gene and the coding region for chloramphenicol acetyltransferase (CAT). Transient transfection of chimeric plasmids demonstrated that the mouse HGF gene promoter containing 70 base pairs of the 5'-flanking sequences were active in mouse fibroblast NIH 3T3 cells and in human
endometrial carcinoma
RL95-2 cells. This basal transcription activity of the HGF promoter was modulated in NIH 3T3 and RL95-2 cells by multiple upstream elements. Three positive elements were identified at positions -2848 to -2674, -1386 to -1231, and -699 to -274, and three negative candidate elements were mapped to positions -1652 to -1386, -964 to -699, and -274 to -70, respectively. By the combination of a series of 5'-end deletion and internal deletion, a cell type-specific negative regulatory element in RL95-2 cells was localized to the nucleotide position -964 to -699. Moreover, the reporter plasmid containing interleukin 6 (IL-6) response element was responsive to IL-6 stimulation in stably transfected NIH 3T3 cells. Our findings revealed a complex pattern of transcriptional regulation of the mouse HGF gene expression.
...
PMID:Structural and functional characterization of the mouse hepatocyte growth factor gene promoter. 830 76
In MCF7 human breast cancer cells, the antiestrogens 4-hydroxy-tamoxifen and ICI 164,384 inhibit the mitogenic activity of epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I). These growth factors also stimulate the expression of cathepsin-D and pS2 genes. Therefore, we studied the effects of antiestrogens on growth factor induction of pS2 and cathepsin-D mRNA. The two antiestrogens strongly inhibited the transcriptional induction of pS2 by growth factors. On the contrary, estradiol and IGF-I or EGF had an additive effect on pS2 mRNA accumulation. Growth factor induction of cathepsin-D was also inhibited by ICI 164,384. By contrast, 4-hydroxytamoxifen had an agonist effect on cathepsin-D and an additive effect on IGF-I-induced mRNA. When 12-O-tetradecanoylphorbol-13-acetate or 8-bromo-
cAMP
(8-Br-cAMP) was used instead of growth factors, similar effects of 4-hydroxytamoxifen and ICI 164,384 were obtained on pS2 (12-O-tetradecanoylphorbol-13-acetate and 8-Br-cAMP) and cathepsin-D (8-Br-cAMP) induction. A mechanism based on the classical competitive inhibition by antiestrogens of estrogen binding and action on the estrogen receptor was very unlikely, as 1) no antigrowth factor activity was obtained with R5020, which was a potent inhibitor of estrogen induction of pS2 and cathepsin-D mRNA; 2) in the Ishikawa
endometrial cancer
cell line, the cathepsin-D gene is unresponsive to estrogen, but was inhibited by antiestrogen after its induction by EGF or 8-Br-cAMP; and 3) the residual estrogen concentration in cells was too low to induce the expression of estrogen-specific genes. However, antiestrogens did not inhibit the expression of all genes induced by growth factors, as they were without effect on IGF-I induction of glyceraldehyde-3-phosphate dehydrogenase mRNA. These results demonstrate that antiestrogens can modulate the transcription of some growth factor-induced genes and strongly suggest that this effect is not due to interference with residual estrogens.
...
PMID:Synthetic antiestrogens modulate induction of pS2 and cathepsin-D messenger ribonucleic acid by growth factors and adenosine 3',5'-monophosphate in MCF7 cells. 834 99
The mouse lactoferrin gene responded to forskolin, 12-O-tetradecanoyl phorbol-13-acetate, and epidermal growth factor (EGF) stimulation via two adjacent enhancer elements, the
cAMP
response element (CRE) and EGF response element (EGFRE), collectively referred to as the mitogen response unit. In this report, we examined the minimal promoter and enhancer elements of the mouse lactoferrin gene that are required for EGF-induced transcriptional activation. We found that the CRE and noncanonical TATA box (ATAAA) are the minimal promoter elements for basal activity of the chloramphenicol acetyltransferase (CAT) reporter construct whereas the EGFRE is needed for an additional activity induced by EGF in transiently transfected human
endometrial carcinoma
RL95-2 cells (RL95-2). The EGFRE, however, did not function in heterologous promoters [SV 40 and thymidine kinase (TK)]. Therefore, EGF-stimulated lactoferrin gene activity is promoter specific in RL95-2 cells. In transiently transfected cells, EGF and forskolin showed synergistic effects on the CAT reporter that contained both response elements. Mutation made at either element or insertion of extra nucleotides between the two elements severely affected EGF-stimulated activity. Nuclear protein prepared from RL95-2 cells formed three complexes (A, B, and C) with the oligonucleotides containing both EGFRE and CRE in electrophoretic mobility shift assay. A new complex (E) was detected with the nuclear protein of EGF-treated cells. By oligonucleotide competition experiments, we demonstrated that the complex E was generated by protein bound to CRE. EGF-induced binding activity could be abolished by calf intestinal alkaline phosphatase but not by the protein synthesis inhibitor, cycloheximide. Therefore, binding of a preexisting phosphoprotein to the CRE region could be one of the requirements for EGF-induced mouse lactoferrin gene promoter activity.
...
PMID:Promoter-specific activation of mouse lactoferrin gene by epidermal growth factor involves two adjacent regulatory elements. 877 33
Expression of the lactoferrin gene in a variety of tissues is regulated differentially. We have previously demonstrated that the lactoferrin gene is regulated by estrogen and mitogen in mouse uterus. The mouse lactoferrin gene responded to forskolin,
cAMP
, TPA and EGF stimulation via two adjacent enhancer elements, the CRE and EGFRE and collectively referred to as the Mitogen Response Unit (MRU). We found that CRE is responsible for forskolin,
cAMP
and TPA whereas EGFRE is for EGF stimulation. We examined the minimal promoter and enhancer elements of the mouse lactoferrin gene that are required for EGF induced transcriptional activation. We found that the CRE and noncanonical TATA box (ATAAA) are the minimal promoter elements for basal activity of the CAT reporter construct, whereas, the EGFRE is needed for an additional activity induced by EGF in transiently transfected human
endometrial carcinoma
RL95-2 cells (RL95-2). The EGFRE, however, did not function in heterologous promoters (SV 40 and TK). Therefore, EGF-stimulated lactoferrin gene activity is promoter specific in RL95-2 cells. Mutation made at either elements or insertion of extra nucleotides between the two elements, severely affected EGF-stimulated activity. Nuclear protein prepared from RL95-2 cells protected the EGFRE, CRE and noncanonical TATA from DNAase I digestion in a footprinting analysis. Nuclear protein which interacted with the CRE were previously identified as API and CREB. In this study, we isolated a cDNA clone from an RL95-2 expression library that encodes the EGFRE binding protein. Partial sequence of the cDNA clone revealed 100% nucleotide identity with a GC-box binding protein, BTEB2. Protein-protein interaction among the transcription factors could fine-tune the mouse lactoferrin expression in various tissues.
...
PMID:Mouse lactoferrin gene. Promoter-specific regulation by EGF and cDNA cloning of the EGF-response-element binding protein. 978 44
1
2
Next >>