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

The US Food and Drug Administration finally approved the injectable contraceptive Depo-Provera (DMPA) in October 1992, 25 years after its introduction. Women return to a health facility every 90 days for an intramuscular injection of 150 mg DMPA, which provides them 99% effective contraception. Menstrual changes and spotting are the leading reasons for DMPA discontinuation. Eventually, more than 50% of DMPA users develop amenorrhea. During the first year, women gain about 2 kg and weight increases as time passes. Weight gain is the second leading reason for DMPA discontinuation. DMPA may adversely affect glucose tolerance in women at risk for diabetes, but it does not affect cardiovascular or metabolic functions. It may increase the risk of osteoporosis. A rare side effect is convulsions. 1-10% of DMPA users have other central nervous system effects, such as headaches, dizziness, and depression. Itching and rashes may develop. Fertility returns within 1 year after discontinuation. DMPA is linked to low birth weight. It apparently does not harm breast-fed infants or hinder lactation. A World Health Organization study shows that DMPA users less than 35 years old experience a slight increase in breast cancer but a reduced incidence of endometrial cancer. Nurses are instrumental in guiding women as they choose DMPA and in informing them about its potential side effects, including breast cancer risk. They must screen women for pregnancy and evaluate their risk of breast cancer. They must determine whether women are able to return every 3 months for DMPA injections. Women who select DMPA must use other contraception, e.g., barrier protection, within the first 24 hours after initial injection. Nurses should counsel them about the likely menstrual changes to reduce the likelihood of dissatisfaction. They should recommend a daily dose of 1200 mg of elemental calcium and daily exercise of long bones to minimize the risk of developing osteoporosis.
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PMID:Depo-Provera. 849 47

In 22 patients with endometrial carcinoma, Stage I-III (mean age 57.8 years) with obesity, initial and reactive hyperinsulinemia (during glucose load) was revealed. Significant correlations between values of "peak" and field-square of the insulin secretion curve and cytoplasmatic receptors to Estradiol and Progesterone in the tumor were found. In a group of the patients with high values of reactive hyperinsulinemia significantly larger amounts of steroid hormone receptors in the tumor were determined as compared to the group of the patients who had low insulinemia values. On considering these data a possible conclusion was reached as to the modifying influence of hyperinsulinemia on sensitivity of endometrial carcinoma to hormone receptor synthesis in the tumor by insulin.
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PMID:Hyperinsulinemia as a factor modifying sensitivity of endometrial carcinoma to hormonal influences. 850 Apr 94

Endometrial fibroblasts derived from uterine endometrium as controls and endometrial cancer cell lines (Ishikawa and HHUA cells) were analyzed for the induction manner of c-fos and c-jun transcripts in endometrial cancers, some of which are estrogen-dependent in growth. Estrogen increased c-fos expression and protein kinase C (PKC) activity in fibroblasts and Ishikawa cells, but not in HHUA cells. Progesterone diminished c-fos and c-jun expression and PKC activity induced by estradiol in the fibroblasts, but not in Ishikawa cells, which persistently overexpressed c-fos and c-jun. In these cells, 12-0-tetra-decanoylphorbol-13-acetate (TPA) increased c-fos and c-jun expression as did estradiol. Pretreatment with 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7) abolished estrogen-inducible over-expression of c-fos and c-jun. The combination of both estradiol and TPA at maximum effective concentration exerted no additive and synergistic effect on induction of c-fos and c-jun expression. In conclusion, persistent activation of PKC might lead to overexpression of c-fos and c-jun in some endometrial cancers with an estrogen predominant milieu, which might be, at least in part, associated with the transformation or growth potential.
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PMID:Estrogen induces expression of c-fos and c-jun via activation of protein kinase C in an endometrial cancer cell line and fibroblasts derived from human uterine endometrium. 870 84

1. The levels of basic fibroblast growth factor (FGF) expression and secretion and its messenger ribonucleic acid (mRNA) expression in well-differentiated endometrial cancer (Ishikawa) cells were significantly increased by estradiol. 2. This increase was significantly inhibited by tamoxifen, progestins (progesterone, medroxyprogesterone acetate [MPA], and 17 alpha-hydroxyprogesterone), and to some extent danazol, but not by terahydrocortisol and hydrocortisone. 3. Estrogen might stimulate the basic FGF secretion of endometrial cancer cells, at least for neovascularization, and antiestrogenic compounds may inhibit the estrogen-induced event.
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PMID:Antiestrogenic compounds inhibit estrogen-induced expressions of basic fibroblast growth factor and its mRNA in well-differentiated endometrial cancer cells. 959 98

To ascertain one of the biological effects of danazol and progesterone on the uterine endometrial cancer cell line, Ishikawa, we investigated the effects of these steroids on sex hormone-binding globulin (SHBG) mRNA expression by competitive reverse transcription-polymerase chain reaction-Southern blot analysis (RT-PCR-SBA). Estradiol-17beta (E2) in any concentration given did not exert any significant effect on the expression of SHBG mRNA. Danazol and progesterone significantly (P < 0.05) suppressed the expression of SHBG mRNA dose-dependently starting at a concentration of 10(-6) and 10(-8) M, respectively. Progesterone, in a low concentration (10[-10] M) with E2 (10[-8] M), significantly (P < 0.05) increased the expression of SHBG mRNA, but danazol did not. In contrast, danazol and progesterone in high concentrations (10[-6] to 10[-5] M) with E2 (10[-8] M) significantly (P < 0.05) suppressed its expression. The time course study showed the time-dependent decrease of SHBG mRNA level by danazol and progesterone (10[-6] M) with or without E2 (10[-8] M), except for a temporal increase by progesterone. These findings suggest that danazol and progesterone in a superphysiological milieu down-regulate the intracellular SHBG-related steroidal actions, and that progesterone in a physiological milieu with estrogen up-regulates it in a hormone-dependent cell line. A decrease of intracellular SHBG caused by high-dose danazol or progesterone might partly contribute to the abolition of the intracellular estrogen-dominant milieu, and be related to the inhibition of estrogen-dependent growth of some endometrial cancer cells.
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PMID:Effects of danazol and progesterone on sex hormone-binding globulin mRNA expression in human endometrial cancer cell line Ishikawa. 940 86

To clarify the effect of sex steroids on neovascularization in the growth, invasion and metastasis of endometrial cancer, the regulations of acid fibroblast growth factor (FGF-1), basic FGF (FGF-2) and hst-1 (FGF-4) mRNA expressions were studied in well-differentiated endometrial cancer cells under the influence of sex steroids. The levels of FGF-1 and 2 mRNAs in the well-differentiated endometrial cancer (Ishikawa) cells were significantly increased by estradiol. This increase was significantly inhibited by progestins (progesterone, medroxyprogesterone acetate [MPA] and 17 alpha-hydroxyprogesterone) and tamoxifen, but not by tetrahydrocortisol, hydrocortisone and danazol. The expression of FGF-4 mRNA was not altered by sex steroids. Therefore, estrogen might stimulate FGF-2 with FGF-1 secretion of endometrial cancer cells for neovascularization, and antiestrogenic compounds do inhibit estrogen-induced events.
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PMID:Antiestrogenic compounds inhibit estrogen-induced expression of fibroblast growth factor family (FGF-1, 2, and 4) mRNA in well-differentiated endometrial cancer cells. 944 20

The two types of endometrial carcinomas are preceded by precancerous lesions. Type I endometrial carcinomas are most commonly encountered in perimenopausal women with the classical risk factors associated with estrogen exposure: obesity, multiparity, diabetes, estrogen treatment, ... Hyperplasia (simple, followed by complex forms without cellular atypias and subsequently by complex hyperplasias with cellular transformation) precede such cancers. Estrogens exert a promoting effect on these lesions but do not initiate them. Progesterone and progestins exert a preventive and protective effect. However, the progressive loss of steroidal receptors is correlated to the progression of tissular anomalies and to the onset of cytogenetic anomalies and to mutations of p53 anti-oncogene. The preventive role of progestin is well established, but their curative beneficial effect on atypical precursors forms of endometrial cancers and on endometrial carcinomas remains controversial. The second type of endometrial cancer appears during the postmenopause and is characterized by an increased invasiveness and a poor prognosis, devoid of identifiable risks factors, these aggressive cancers are not preceded by hormone-sensitive precancerous lesions, but by an intra-epithelial endometrial carcinoma. This lesion appears most often in an atrophic endometrium. Finally, the two types of precancerous states are characterized by distinct gene anomalies suggesting two different pathogenic mechanisms of cancerisation.
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PMID:[Precancerous states of the endometrium: hormonal aspects]. 952 83

The uterine endometrium responds to unopposed estrogen stimulation with rapid cell proliferation. Progesterone protects the endometrium against the hyperplastic effects of estradiol (E2) through progesterone receptors (PRs), of which two isoforms are expressed: human (h) PRA and PRB. hPRB has a longer NH2 terminus and may function differently from hPRA. Thus, the relative expression of hPRA:hPRB is likely to be important for the action of progesterone. We hypothesized that the hPRA:hPRB ratios may be abnormal in endometrial cancer, leading to a lack of normal progesterone protection against the growth-promoting effects of E2. To test this hypothesis, well-differentiated Ishikawa endometrial cancer cells were compared to poorly differentiated Hec50 and KLE cells. Reverse transcription-PCR was chosen as a sensitive method to detect transcripts for the two forms of PR. The relative expression of PR isoforms under hormonal stimulation was determined by Western blotting. Transient transfections of hPRA and hPRB into endometrial cells allowed the evaluation of the transcriptional activity of each isoform independently on reporter gene transcription under the control of a simple progesterone response element-containing promoter. The effect of coexpressing the estrogen receptor on PR expression was also studied. Ishikawa cells (well-differentiated) express both hPRA and hPRB. Both isoforms, but predominantly hPRB, are up-regulated by E2 and not by tamoxifen or the pure antiestrogen ICI 182,780. Hec50 and KLE cells (poorly differentiated) express only hPRA. No hPRB is present in the poorly differentiated cells, and it is not induced by estrogen receptor expression and/or estrogen treatment. In all cells, hPRB expression, whether endogenous or produced as a result of transfection, acts as a stronger transcription factor than hPRA on a simple progesterone-dependent promoter. We speculate that down-regulation of hPRB may predict for poorly differentiated endometrial cancers that do not respond to progestin therapy.
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PMID:Selective down-regulation of progesterone receptor isoform B in poorly differentiated human endometrial cancer cells: implications for unopposed estrogen action. 958 25

The expression of luteinizing hormone-releasing hormone (LHRH) and its receptors has been demonstrated in a number of human malignant tumors, including cancers of the breast, ovary, endometrium and prostate. These findings suggest the presence of an autocrine regulatory system based on LHRH. Recent studies in our laboratory have demonstrated that the function of LHRH produced by ovarian cancer cells is the inhibition of their proliferation. Dose-dependent antiproliferative effects of LHRH-agonists have been observed by several laboratories in cell lines derived from the above cancers. Interestingly, also LHRH-antagonists have marked antiproliferative activity in most of the ovarian, breast and endometrial cancer cell lines tested so far, indicating that the dichotomy of LHRH-agonists/LHRH-antagonists is not valid for the LHRH-system in cancer cells. In addition, our data suggest that the classical LHRH receptor signal transduction mechanisms known from the pituitary (phospholipase-C, protein kinase C, adenylyl cyclase) are not involved in the mediation of LHRH effects in cancer cells. Data obtained by several groups, including ours, rather suggest that LHRH analogs interfere with the signal transduction of growth-factor receptors and related oncogene products associated with tyrosine-kinase activity. The mechanism of action is probably an LHRH-induced activation of a phosphotyrosine phosphatase, counteracting the effects of receptor associated tyrosine kinase. In our hands, LHRH analogs virtually blocked the EGF-induced MAP-kinase activity of ovarian and endometrial cancer cells. The pharmacological exploitation of this mechanism might provide promising new therapies for these cancers.
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PMID:Effects of LHRH-analogues on mitogenic signal transduction in cancer cells. 969 74

One hundred and ninety asymptomatic postmenopausal women were examined by transvaginal sonography. Progesterone challenge test (PCT) was performed in 46 of the women with measured endometrial thickness equal to or greater than 6 mm. PCT positive were 32 of these women and they underwent curettage. Endometrial hyperplasia was detected in 18 women and in 2 of the atypical hyperplasia was verified. The authors conclude that PCT is a convenient and safe screening method for women at high risk for endometrial cancer.
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PMID:Progesterone challenge test for evaluation of endometrial hyperplasia in postmenopausal women. 970 8


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