Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0476089 (endometrial cancer)
11,379 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Presence of alternatively spliced-estrogen receptor (ER) mRNA variants has been revealed in the breast cancer tissues. The ER variants transcribed from these mRNA variants were supposed to cause changes in the estrogen responsiveness of breast cancer. Although uterine endometrial cancer also has an estrogen-dependent profile, these ER mRNA variants have not yet been reported in the tumor. In the present study, we attempted to detect the exon 7 deletion- (del.7-) and exon 5 deletion (del.5) ER mRNA variants in normal human uterine endometrium (hEM) and uterine endometrial cancer tissue (hEC) by the use of reverse transcription-polymerase chain reaction-Southern blotting (RT-PCR-SB) with the PCR primers: hE4 (forward), hE6 (reverse), and hE8 (reverse), which were located in exons 4, 6, and 8, respectively. Two major products were generated from RNAs of both hEM and hEC with primers hE4 and hE8. The nucleotide sequence of the longer product was identical to exon 4-8 of human ER cDNA, whereas that of the shorter one completely deleted exon 7. Moreover, when the RT-PCR was done with the primers hE4 and hE6, the shorter product lacking exon 5 was detected with the longer one having the same sequence as exon 4-6 of human ER cDNA. Since the RT-PCR-SB with primers hE4 and hE8 produced a very low or undetectable level of the signals corresponding to del.5 ER mRNA variant, the level of del.7 ER mRNA variant seemed to be higher than that of del.5 ER mRNA variant.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Presence of alternatively spliced-estrogen receptor mRNA variants in normal human uterine endometrium and endometrial cancer. 754 77

We studied the expressions of aberrant epidermal growth factor receptor (EGFR) gene or erbB-2, which is highly homologous to EGFR gene, and erbA or estrogen receptor (ER) gene, which is highly homologous to erbA, as a preliminary study, to know which oncogene expressions are associated with the development of endometrial cancers. ErbB-2 mRNA lacked only extracellular domain (EX), suggesting the lack of downregulation of erbB-2 expression by a ligand, which led to regulated tyrosine kinase activity. Mutated DNA binding domain of ER mRNA were found in 3 of the 13 cases, suggesting the promotion disorder of estrogen-inducible proteins in these 3 endometrial cancers. The behavior of aberrant erbB-2 and ER gene co-expressions is considered of similar to that of erbA and erbB co-expressions in the chicken introduced by the avian erythroblastosis virus, which leads to the development of erythroblastosis in the chick, and seems to be associated with the development of endometrial cancer.
...
PMID:Preliminary study of oncogene expressions in endometrial cancers. Aberrant estrogen receptor gene and erbB-2 expressions. 774 15

The development and growth of gynecological cancers are related to steroid hormone actions. Alternatively, this prompts us to study biological contribution of sex steroids for invasion and metastasis in gynecological cancers. The first step of metastasis is the detachment of tumor cells. The adherens junction forms a main cell-to-cell junctional complex, mainly consisting of E-cadherin, alpha- and beta-catenins, etc. Estrogen suppressed the expression of their mRNAs, and the adhesive function of cells via adherens junction in endometrial cancer cells. Progestin and danazol reversed the estrogen-induced suppression. Estrogen enhanced invasiveness of endometrial cancer cells though the reconstituted basement membrane and interstitium using the Boyden chamber. Progestin reduced the estrogen-induced invasiveness. The final step of metastasis is tumor-derived neovascularization for growth of metastatic cancer cells. Progestin inhibited basic fibroblast growth factor (FGF) activity, which mainly contribute to tumor-derived neovascularization, regardless of growth-inhibition in some endometrial cancers. Progestin inhibits basic FGF in well-differentiated (WD) endometrial cancer cells, but not in poorly differentiated (PD) endometrial cancer cells. TNP470, a inhibitor of vessel endothelial proliferation, inhibited directly basic FGF in the PD. Therefore, the adequate combination therapy of progestin and TNP470 could efficiently inhibit angiogenic potential of heterologous endometrial cancers. The ratio of estrogen receptor exon 5 splicing variant (ER delta E5) to wild type-ER mRNA expression increased in some metastatic lesions of cancers. The dominant expression of ER delta E5 mRNA might be related to metastatic potential of gynecological cancers. Progesterone receptor from A (PR-A), initiated from in-frame AUG present in the PR from B (PR-B) mRNA, lacks the N-terminal 164 amino acids of PR-B, and acts as a progestin-dependent, trans-dominant repressor of PR-B function and other steroid receptor function. The expression of PR-B mRNA was dominantly expressed in all metastatic gynecological cancers given. This might be related to metastatic potential of gynecological cancers. To know tumorigenic potential of sex steroid receptors, ER, PR-A and PR-B genes were transfected to NIH3T3 cells. Transfected cells with PR-A gene alone formed a few colonies in double soft agar. On the other hand, the cells with PR-B and ER genes under the presence of estradiol formed plenty of colonies. Therefore, overexpression of PR-B under the absence of PR-A might be related to tumorigenic potential. In conclusion, estrogen could enhance some steps of metastasis in endometrial cancers, and progestin could inhibit the estrogen-induced events, regardless of growth-inhibition. Relative over-expression of ER exon 5 splicing variant, and PR-B might contribute to metastatic potential in gynecological cancers.
...
PMID:[Endocrinological contribution for invasion and metastasis in gynecological cancers]. 880 31

Breast cancer tissue has been shown to contain alternatively spliced estrogen receptor (ER) mRNA variants which may result in alternate ER proteins. These ER variants lack specific functional domains and may alter breast cancer cells responses to both estrogen and antiestrogens. Specifically, ER variants might play a role in Tamoxifen resistance in breast cancer patients, as well as the development of endometrial carcinoma, an estrogen-dependent tumor, in patients taking this medication. We investigated the presence of ER variants in normal human endometrium and endometrial carcinoma. Ribonuclease protection assays (RPA) demonstrated ER mRNA variants in the DNA and hormone-binding domains. The reverse transcription-polymerase chain reaction (RT-PCR) assay was used to examine the ER complementary DNA (cDNA) from 25 patients, and generated two major products in both the exon 2 to 5 and 4 to 8 regions. Southern blot analysis of PCR products revealed exon 4 and 7 deletions in all 25 endometria without any qualitative differences in variant expression among premenopausal, postmenopausal, and adenocarcinoma samples. Cloning and sequencing of cDNA variants definitively identified exact deletions of either exon 4 or exon 7. These results demonstrate significant levels of ER mRNA splice variants as well as full-length ER mRNA in normal and neoplastic endometria.
...
PMID:Estrogen receptor mRNA splice variants in pre- and postmenopausal human endometrium and endometrial carcinoma. 910 5

Breast cancer tissue has been shown to contain alternatively spliced estrogen receptor alpha (ER-alpha) mRNA variants, which have altered biological activities compared to the full-length ER-alpha. The development of endometrial cancer, as well as drug resistance in breast cancer patients undergoing tamoxifen therapy, may represent altered ER-alpha function secondary to specific exon deletions. While the literature is replete with ER mRNA variant data, little information is available regarding the presence and function of endometrial ER variant proteins. We evaluated the presence of human ER-alpha mRNA and protein variants in six premenopausal, six postmenopausal, and six endometrial carcinoma samples. Reverse transcription-polymerase chain reaction, DNA hybridization, and sequencing techniques identified exon 4, exon 5, and exon 7 mRNA splice variants in all patients as well as MCF-7 and Ishikawa cell lines. Presence of translated proteins for full-length ER-alpha, as well as splice variants, was investigated by Western blot analysis using antibodies directed against the N-terminus, hinge region, and C-terminus portions of the ER. These experiments confirmed the presence of immunopositive protein bands of approximately 64-66 kDa in all patients corresponding to wild-type ER-alpha. A protein band migrating at 41 kDa, consistent with an exon 5 splice variant, was only seen in endometrial adenocarcinoma samples. Premenopausal and postmenopausal endometrial samples did not contain detectable amounts of ER splice variant protein. Human ER-alpha mRNA variants are present in all human endometrial samples, but detectable levels of variant proteins are only observed in patients with endometrial adenocarcinoma.
...
PMID:Expression of estrogen receptor alpha mRNA and protein variants in human endometrial carcinoma. 1038 49

The present study was conducted to investigate the mechanism of the response of human uterine endometrial carcinoma cells, RL95-2 and KLE, to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). RL95-2 cells were highly responsive to TCDD in terms of cytochrome P4501A1 (CYP1A1), cytochrome P4501B1 (CYP1B1), and plasminogen activator inhibitor-2 (PAI-2), whereas KLE cells showed little stimulatory effects only at high doses. Neither showed any growth inhibition upon exposure to TCDD. KLE cells expressed higher levels of aryl hydrocarbon receptor (AhR) than RL95-2 and gel mobility shift assay also identified more liganded AhR-ARNT complex bound to xenobiotic response elements (XRE). TCDD had no downregulatory effects on the expression of either AhR or the estradiol receptor (ER). Though both cell types expressed ER-alpha almost equally, immunofluorescence demonstrated a defect in its nuclear translocation in KLE cells where ER-alpha was mainly cytoplasmic and estradiol-17beta (E(2)) was unable to translocate it to the nucleus. However, both cells were nonresponsive to E(2) in terms of transcriptional activation and transient expression of normal ER-alpha restored the E(2) responsiveness. Transient expression of ER-alpha in KLE cells also restored its responsiveness to TCDD on transcriptional activation. Collectively, these results indicate that ER-alpha acts as a positive modulator in regulation of the TCDD-inducible genes.
...
PMID:Role of estradiol receptor-alpha in differential expression of 2,3,7, 8-tetrachlorodibenzo-p-dioxin-inducible genes in the RL95-2 and KLE human endometrial cancer cell lines. 1041 8

We assessed the relative expression of oestrogen receptor (ER)alpha and oestrogen receptor (ER)beta mRNAs in 36 human endometrial cancers using a multiplex polymerase chain reaction (PCR). To determine whether or not the expression of ER subtypes in endometrial cancers is associated with clinicopathological parameters, we examined correlations between ER subtypes and age, tumour grade and depth of myometrial invasion. Using multiple regression analysis, myometrial invasion showed a significant correlation with ER-beta: ER-alpha ratio (r = 0.54, P = 0.0007). The ER-beta:ER-alpha ratio was high in advanced invasive carcinoma. Western blotting analysis showed that ER-beta proteins were highly expressed in comparison with ER-alpha proteins in endometrial cancer with severe myometrial invasion. Our results suggest that ER-beta is important in the progression of myometrial invasion.
...
PMID:Oestrogen receptor beta expression and depth of myometrial invasion in human endometrial cancer. 1120 52

Estrogen receptors (estrogen receptor alpha, ER) belong to a family of ligand-modulated transcription factors that play an important role in the progression of such tumors as breast and endometrial cancers. Functional domains, a set of mutations and variants produced by internal deletions of ER mRNA, have mainly been identified in breast cancer. Experimental results suggest that the presence of variants may result in different proteins which differ in activity and modulate the ER signaling pathway differently. We analyzed samples from 21 cases of endometrial hyperplasia and from 29 cases of endometrial cancer for the presence of internal exons and exon deletion variants of ER mRNA. ER and progesterone receptor (PgR) proteins were measured using Western blot technique in all endometrial cancer samples. We found that absence of the wild-type exon PCR product of ER mRNA in a sample increased in parallel with malignant potential in both sample types, whereas the number of exon deletion variants detected in the same sample decreased in cases of malignancy. The precise deletions of the respective exons suggest that they are probably the result of splicing errors. A relatively high number of variants in hyperplasia samples may indicate the important role of ER mRNA variants in the physiologic regulation of transcription in estrogen-sensitive genes. Eleven of 29 adenocarcinomas expressed a 62-kDa ER protein, truncated at the amino terminal, whereas all but one sample expressed a short 52 kDa variant ER protein. Our results suggest that differing ER proteins are generally present in human endometrial adenocarcinomas and that they may influence the estradiol signaling pathways.
...
PMID:Exon deletions and variants of human estrogen receptor mRNA in endometrial hyperplasia and adenocarcinoma. 1124 Jun 64

It is well known that the functions of reproductive organs are regulated by sex steroids and their receptors and it is hypothesized that the progression of neoplasms that originate from the reproductive organs is influenced by them. However, the correlation between sex steroids and tumor progression, especially tumor invasion, is not well known in endometrial carcinoma. In our study, we focused on the influence of estrogen and its receptor in invasion and matrix metalloproteinases (MMPs), which are known to be important in tumor invasion, as well as on endometrial carcinoma cells. The growth of Ishikawa cells, to which an estrogen receptor-alpha expressing vector was transfected, was accelerated by 17 beta-estradiol as was the acceleration of the expression of cyclin D1. By invasion assay, in conditions with 17 beta-estradiol, the invasiveness of Ishikawa cells was enhanced. Furthermore, according to the accelerated invasiveness, the expression of MMP-1, -7 and -9 and Ets-1 was enhanced. These results suggest that activation of ER-alpha by estrogen results in tumor progression by stimulating cell growth and invasiveness via acceleration of the expression of MMPs.
...
PMID:Acceleration of invasive activity via matrix metalloproteinases by transfection of the estrogen receptor-alpha gene in endometrial carcinoma cells. 1211 20

Overexpression of cdc25B, an important cell cycle regulator, has been shown to result in mammary gland hyperplasia in transgenic mice and to increase steroid hormone responsiveness as a direct coactivator of the estrogen receptor (ER). We investigated the potential role of cdc25B in the pathogenesis of endometrial carcinomas in conjunction with ER-alpha. We examined the expression of cdc25B and phosphorylated ER-alpha in 4 archived human specimens of normal endometrium; 7 endometrial hyperplasia with or without atypia; 32 endometrioid endometrial carcinoma (EEC), including 20 low-grade (grade 1) and 12 high-grade (grade 2 or 3) tumors; and 18 endometrial cancers with aggressive histological subtypes (uterine papillary serous carcinoma and clear cell carcinoma, UPSC/CCC) by immunohistochemistry with monoclonal antibodies. Expression of cdc25B and phosphorylated ER-alpha was increased in endometrial hyperplasia and atypical hyperplasia compared with normal secretory endometrium. Ninety percent (18 of 20) of the low-grade EEC expressed cdc25B at a high level, whereas only 42% (5 of 12) of the high-grade EEC did so (chi(2) = 8.7; P < 0.01). Sixty-five percent (13 of 20) of the low-grade EEC expressed phosphorylated ER-alpha at high levels, but only 17% (2 of 12) of high-grade EEC did so (chi(2) = 7.0; P < 0.01). Coordinate high-level expression of phosphorylated ER-alpha and cdc25B occurred in 65% (13 of 20) of low-grade EEC but in only 17% (2 of 12) of the high-grade EEC (chi(2) = 7.0; P < 0.01). In the UPSC/CCC tumors, only 22% (4 of 18) of the tumors expressed phosphorylated ER-alpha at high-levels. However, 83% (15 of 18) of these carcinomas showed high expression of cdc25B (chi(2) = 13.5; P < 0.01). The majority of the UPSC/CCC (15 of 18) did not show coordinate high expression of phosphorylated ER-alpha and cdc25B. Our findings show that in endometrial hyperplasia and low-grade EEC, coordinate increase in cdc25B and phosphorylated ER-alpha occurs. However, in UPSC/CCC, cdc25B is highly expressed without coordinate increase in phosphorylated ER-alpha. Cdc25B may play important roles in the development and progression of EEC and UPSC/CCC by different mechanisms.
...
PMID:Coordinate expression of Cdc25B and ER-alpha is frequent in low-grade endometrioid endometrial carcinoma but uncommon in high-grade endometrioid and nonendometrioid carcinomas. 1455 3


1 2 Next >>