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Query: UMLS:C0476089 (
endometrial cancer
)
11,379
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Endometrial adenomatous and atypical hyperplasia are the histopathological pictures that more frequently may develop into an adenocarcinoma. It is believed that a hormonal action may favour the genesis of
endometrial cancer
. We studied the plasmatic levels of some steroids, considered to be responsible for neoplastic changes, in patients with adenomatous and atypical hyperplasia. With this object we measured plasmatic levels of estrone, estradiol, androstenedione,
DHEA
-S and testosterone in postmenopausal patients with adenomatous and atypical hyperplasia and in fertile women, both in proliferative and secretory phases. We didn't find any difference in the steroid pattern in the two groups.
...
PMID:Behavior of some steroids in endometrial adenomatous and atypical hyperplasia. 622 17
Estrogen sulfoconjugation previously was reported in normal endometrium and in RL95-2 cells, a cell line derived from a human
endometrial cancer
maintained in continuous in vitro culture. In the present study the estrogen sulfurylation activity in the cytosolic fraction of RL95-2 cells was characterized using [3H]estrone as substrate. Estrone sulfate was separated from unreacted estrone by thin layer chromatography. Activity was proportional to cytosol concentration, with a pH optimum at pH 8. There was marked temperature dependence between 24 and 40 C. The apparent Km for estrone conjugation was 3.6 nM, with a maximum velocity of 135 fmol/micrograms DNA . h. No complex kinetic behavior was found at estrone concentrations up to 1 microM. The apparent Km for the cosubstrate 3'-phosphoadenosine 5'-phosphosulfate was 0.6 microM. Inhibition experiments demonstrated that the sulfurylating activity studied under these conditions was specific for estrogens. Only estradiol and estriol, in addition to estrone itself, inhibited conjugation to any significant degree.
Dehydroepiandrosterone
had only 1% the inhibitory activity of estrone. Other androgens, corticoids, progestins, phenols, nonsteroidal estrogens and antiestrogens, and bile acids had no significant effects on the sulfurylation of estrone. An estrogen-sulfoconjugating activity with the characteristics of estrogen sulfotransferase (EST) was demonstrated in RL95-2 cells. The Km of EST for estrone in the RL95-2 cells closely approximated the value reported for the enzyme in normal endometrium. The affinity of EST for estrogens is within the range of the Kd of estrogen receptor and of the physiological concentrations of estrogens reported in the endometrium, suggesting that EST could serve as a regulator of intracellular estrogen levels.
...
PMID:Characterization of cytosolic estrogen sulfotransferase from RL95-2 endometrial cancer cells. 659 68
The physiological role of dehydroepiandrosterone (DHEA) and DHEA sulphate (DHEAS) is poorly understood. It depends in a large part on their transformation into testosterone and estradiol. The capacity of DHEA as a neurosteroid, the recent discovery of putative specific DHEA receptors on endothelial and vascular smooth muscle cells, the steady decrease of DHEA production from the 40s on, together with certain human epidemiologic data as well as various beneficial effects of
DHA
supplementation in rodents have suggested the possibility that this steroid is involved in cognitive and memory, metabolic and vascular, immune and sexual functions and in their aging. However, epidemiologic studies are conflicting, and no well-designed clinical trials have definitely substantiated the role of DHEA in these functions in humans, or the utility and safety of DHEA supplementation. However, beneficial effects seem plausible in women with several conditions according to the results of double-blind placebo-controlled trials: the dose of 30 to 50 mg seems beneficial to the mood, sense of well being and sexual desire and activity of women with adrenal insufficiency. The only long-term trial of supplementation devoted to women over 60 reported significant increases in bone mineral density and, in the 70-79-year-old subgroup, in sexual desire, arousal, activity and satisfaction. The dose of 200 mg also proved to decrease disease activity in systemic lupus erythematosus. Lastly, high DHEA doses have improved mood in various groups of patients of any age and gender with depressive symptoms. The use of DHEA therapy may also be discussed in women of any age when a trial of androgen supplementation seems justified because of the existence of an inhibited sexual desire or a sexual arousal disorder associated with documented androgen deficiency. The rather weak conversion of DHEA into testosterone protects from the risk of overdosing associated with testosterone preparations. However, it must be realized that DHEA is also converted into estradiol, which may be a risk factor for breast or
endometrial cancer
in postmenopausal women. Unlike women, no consistent beneficial effect has been found for men in the placebo-controlled trials. The present data do not exclude a role of DHEA in other conditions, but this remains to be properly established. This paper includes practical considerations on dosage to be used, contraindications and follow-up.
...
PMID:Androgen therapy with dehydroepiandrosterone. 1455 20
Following the arrest of estradiol secretion by the ovaries at menopause, all estrogens and all androgens in postmenopausal women are made locally in peripheral target tissues according to the physiological mechanisms of intracrinology. The locally made sex steroids exert their action and are inactivated intracellularly without biologically significant release of the active sex steroids in the circulation. The level of expression of the steroid-forming and steroid-inactivating enzymes is specific to each cell type in each tissue, thus permitting to each cell/tissue to synthesize a small amount of androgens and/or estrogens in order to meet the local physiological needs without affecting the other tissues of the organism. Achieved after 500 million years of evolution, combination of the arrest of ovarian estrogen secretion, the availability of high circulating levels of
DHEA
and the expression of the peripheral sex steroid-forming enzymes have permitted the appearance of menopause with a continuing access to intratissular sex steroids for the individual cells/tissues without systemic exposure to circulating estradiol. In fact, one essential condition of menopause is to maintain serum estradiol at biologically inactive (substhreshold) concentrations, thus avoiding stimulation of the endometrium and risk of
endometrial cancer
. Measurement of the low levels of serum estrogens and androgens in postmenopausal women absolutely requires the use of MS/MS-based technology in order to obtain reliable accurate, specific and precise assays. While the activity of the series of steroidogenic enzymes can vary, the serum levels of
DHEA
show large individual variations going from barely detectable to practically normal "premenopausal" values, thus explaining the absence of menopausal symptoms in about 25% of women. It should be added that the intracrine system has no feedback elements to adjust the serum levels of
DHEA
, thus meaning that women with low
DHEA
activity will not be improved without external supplementation. Exogenous
DHEA
, however, follows the same intracrine rules as described for endogenous
DHEA
, thus maintaining serum estrogen levels at substhreshold or biologically inactive concentrations. Such blood concentrations are not different from those observed in normal postmenopausal women having high serum
DHEA
concentrations. Androgens, on the other hand, are practically all made intracellularly from
DHEA
by the mechanisms of intracrinology and are always maintained at very low levels in the blood in both pre- and postmenopausal women. Proof of the importance of intracrinology is also provided, among others, by the well-recognized benefits of aromatase inhibitors and antiestrogens used successfully for the treatment of breast cancer in postmenopausal women where all estrogens are made locally. Each medical indication for the use of
DHEA
, however, requires clinical trials performed according to the FDA guidelines and the best rules of clinical medicine.
...
PMID:All sex steroids are made intracellularly in peripheral tissues by the mechanisms of intracrinology after menopause. 2554 56
The relationship between intake of fish and n-3 fatty acids and
endometrial cancer
risk has not been consistent across epidemiological studies. We quantitatively assessed the aforementioned association through a systematic review and meta-analysis. PubMed and Embase were searched through March 2017 for eligible epidemiological studies. Fixed or random-effects models were used to pool relative risks (RRs) and 95% confidence intervals (CIs). The dose-response relationship was also evaluated. Based on the literature search, five prospective studies and 11 case-control studies were identified. All 16 studies were categorized as high-quality studies. After pooling available risk estimates, no significant association was detected between overall fish intake and
endometrial cancer
risk. In subgroup analyses, every one additional serving/week of fish intake was significantly associated with inversed
endometrial cancer
risk in studies adjusted for smoking (RR (95% CI): 0.95 (0.91-1.00)), or studies performed in Europe (RR (95% CI): 0.90 (0.84-0.97)), but not in other tested subgroups. In studies conducted in Asia, there was significant positive association (RR (95% CI): 1.15 (1.10-1.21)). Regarding n-3 PUFA intake, marginally inverse associations of high EPA or
DHA
intake were detected (EPA: RR (95% CI) = 0.79 (0.61-1.04);
DHA
: RR (95% CI) = 0.85 (0.64-1.11)). Dose-response analyses suggested a significant nonlinear relationship between
DHA
intake and
endometrial cancer
risk (p: 0.04). Overall, this meta-analysis suggests that intake of n-3 PUFA may be inversely associated with
endometrial cancer
risk at some level of evidence, although the exact relationship, especially for fish intake, needs further characterization. Further well-designed studies are warranted.
...
PMID:Dietary n-3 polyunsaturated fatty acids, fish consumption, and endometrial cancer risk: a meta-analysis of epidemiological studies. 2920 77