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)

Age is the most important risk factor for the development of breast cancer. The risk of breast cancer continues to increase in American women until the age of 80 years. A family history of breast cancer helps identify those who possibly have the highest risk of developing breast cancer; however, most women who develop breast cancer do not have a first-degree relative with a history of breast cancer. Currently, the Gail model is a commonly used model to identify risk, and this model has now been validated in several populations of women undergoing screening for breast cancer. The first large-scale breast cancer prevention trial investigating the preventive effects of tamoxifen has demonstrated a decrease in the development of breast cancer by almost 50% in the women in the tamoxifen treatment arm as compared with those receiving placebo. The NSABP P-1 trial was the largest of the three tamoxifen breast cancer prevention trials and had the greatest power to detect a difference between the two treatment groups in breast cancer events. This trial also included the largest percentage of postmenopausal women. It is unclear why the Italian and Royal Marsden Hospital trials had negative results regarding the preventive effects of tamoxifen. These two trials were strikingly different from the NSABP P-1 trial, however, and they included a different population of women. The issues surrounding the use of HRT for treatment of hot flashes in the Italian and Royal Marsden Hospital trials adds to the controversy concerning the negative results of these trials. The new SERM, raloxifene, has shown promise in preliminary studies as a preventive agent for breast cancer. The STAR trial will open soon and will evaluate the efficacy of raloxifene in preventing breast cancer in a prospective fashion, comparing its efficacy with tamoxifen treatment. Other endpoints will evaluate side effects such as menopausal symptoms, endometrial cancer, thromboembolic events, and benefits regarding serum lipids and incidence of osteoporotic bone fractures. The development of SERMs results from an understanding of novel mechanisms of ER modulation and allows targeting for favorable effects in specific tissues. The challenge is to develop an ideal SERM that is effective in preventing breast cancer and does not increase the risk of endometrial cancer, while providing beneficial estrogenic effects on serum lipids and bone mineral density changes. Estrogen receptor-mediated intracellular processes are complex. There are at least two different types of estrogen receptors. The alpha receptors predominate in the breast and uterus, and the beta receptors predominate in the bone and blood vessels. Many proteins also interact with these receptors as co-activators or co-repressors. Transcription-activating factors modulate the effects of estrogen on its target genes. Future prevention strategies may use a combined targeted approach to inhibit ER-mediated cancer progression pathways. The retinoids are under investigation in prevention studies for a multitude of cancers, because they have been shown to inhibit cellular proliferation and to induce cellular differentiation. The retinoid 4HPR was selected for use in breast cancer prevention studies because of its low toxicity profile and prevention efficacy in preclinical studies. It is now being used in combination with tamoxifin in a phase II breast cancer prevention trial. Multiple surrogate endpoint biomarkers are being measured before and after treatment, including measurement of serum IGF-I levels. Future directions in breast cancer prevention include the development of more potent hormonal therapies that completely inhibit ER-mediated cancer progression and, ultimately, multitargeted therapies involving agents that work synergistically.
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PMID:Chemoprevention of breast cancer in the older patient. 1068 75

In the mid 1980s when tamoxifen was shown to be associated with endometrial neoplasia there was a renewed interest in another SERM compound, raloxifene. Experimental animal data suggested that raloxifene did not stimulate the endometrium as tamoxifen does while having similar anti-oestrogenic effects in breast tissue as tamoxifen. Clinical data has now shown that raloxifene does not stimulate the endometrium in postmenopausal women. It results in no hyperplasia, no increase in endometrium thickness or polyp formation and virtually no proliferation. Further studies are necessary to see if long-term raloxifene use will reduce the risk of endometrial cancer. In studies of raloxifene as treatment for osteoporosis, when viewed as a secondary endpoint there was a significant reduction in risk of new onset breast cancer. Further studies with breast cancer as a primary endpoint are ongoing (the STAR Trial).
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PMID:Update on raloxifene to prevent endometrial-breast cancer. 1105 20

Women who are at increased risk for developing breast cancer can be identified using quantitative risk assessment models that provide valid estimates of risk. The Breast Cancer Prevention Trial (BCPT, P-1) demonstrated that tamoxifen can reduce the incidence of both invasive and noninvasive breast cancer as well as of bone fractures in women at increased risk. These benefits accrue at the expense of increased risk of endometrial cancer, thromboses, cataracts, and possibly diminished quality of life in postmenopausal women. All premenopausal women with a 5-year risk of developing invasive breast cancer greater than 1.67% derive net benefit from using tamoxifen to reduce the risk. Subset analyses of older postmenopausal women taking raloxifene for the treatment of osteoporosis indicate reduction of breast cancer incidence by more than 70%. These findings led the National Surgical Adjuvant Breast and Bowel Project (NSABP) to design and launch the STAR trial (P-2, the Study of Tamoxifen and Raloxifene). Eligible women are at least 35 years of age and postmenopausal, and they must have either lobular carcinoma in situ (LCIS) or a 5-year risk of invasive breast cancer of at least 1.67% as determined by the Gail model [M. H. Gail et al., J. Natl. Cancer Inst. (Bethesda), 81: 1879-1886, 1989]. Subjects are randomly assigned to receive either tamoxifen 20 mg or raloxifene 60 mg daily in a double-blind, double-dummy design. The trial is designed to recruit a total of 22,000 postmenopausal women and is powered to demonstrate superior efficacy of either agent or their equivalence in reducing the incidence of primary breast cancer. Additional end points will include the incidence of cardiovascular events and bone fractures. Thromboembolic events and endometrial cancer are the predicted toxicities. Ancillary studies of cognitive function will also be performed. Raloxifene should not be used for the reduction of breast cancer risk outside the context of the STAR trial.
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PMID:Follow-up of the breast cancer prevention trial and the future of breast cancer prevention efforts. 1191 33

The groundwork for making the concept of breast cancer chemoprevention a clinical reality began over a century ago. Although tamoxifen's first clinical use was for the treatment of breast cancer, the earliest animal studies with the drug provided the scientific basis for chemoprevention. The extensive clinical experience, safety and laboratory data have made tamoxifen the current standard-of-care for the prevention of breast cancer in women at elevated risk. The STAR trial will address the value of raloxifene as a chemopreventative in postmenopausal women. Results will be available by 2005. Newer compounds are under development which hold the promise of expanded efficacy and narrower side-effect profile. These compounds will function as multifunctional medicines and will hold the promise of preventing breast and endometrial cancer, while providing the beneficial effects of preventing osteoporosis and coronary heart disease.
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PMID:Chemoprevention of breast cancer: current and future prospects. 1254 69

An individual woman's level of risk for the development of invasive breast cancer can be accurately estimated using the Gail model. This model is not appropriate for use in women with prior breast cancer (invasive or in situ) or a family history suggestive of a genetic predisposition. Tamoxifen is an option for breast cancer risk reduction. The magnitude of benefit varies based on the factors that increase a woman's level of risk, but benefit has been seen in all risk subgroups that have been studied. The risks associated with tamoxifen for prevention vary with menopausal status. In premenopausal women, there are no life threatening toxicities, and quality-of-life issues predominate. In postmenopausal women, the increased risk of endometrial cancer and venous thrombosis mandate a careful assessment of the presence of other risk factors for these conditions prior to considering tamoxifen for prevention. At present, prevention options for the high-risk woman include surveillance, tamoxifen for five years, participation in the STAR trial (if postmenopausal), and bilateral prophylactic mastectomy.
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PMID:The surgeon's role in breast cancer chemoprevention. 1568 11

Selective estrogen receptor modulators (SERMs) are compounds that display mixed estrogen agonist/antagonist activity. Currently, four SERMs are licensed for clinical use: tamoxifen, toremifene, clomifene and raloxifene. The STAR and RUTH trials have provided useful data about the potential role of SERMs in the primary prevention of breast cancer and cardiovascular disease in postmenopausal women. New-generation SERMs, such as bazedoxifene, arzoxifene, lasofoxifene and ospemifene, are currently being evaluated. The aim is to find a SERM that conserves the skeleton and prevents breast cancer without increasing the risk of endometrial cancer and venous thromboembolism, and without inducing hot flushes. Technological advances in the study of estrogen receptor activation will provide key information for drug development.
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PMID:The future of the new selective estrogen receptor modulators. 1744 65

Excessive exposure to estradiol represents the main risk factor for endometrial cancer. The abnormally high estradiol levels in the endometrium of women with endometrial cancer are most likely due to overproduction by the tumour itself. Endometrial cancer cells express the genes encoding the steroidogenic enzymes involved in estradiol synthesis. Here we used RT-PCR and Western blot to show that the nuclear receptors SF1 and LRH1, two well-known regulators of steroidogenic gene expression in gonadal and adrenal cells, are also expressed in endometrial cancer cell lines. By transient transfections, we found that SF1 and LRH1, but not the related nuclear receptor NUR77, can activate the promoters of three human steroidogenic genes: STAR, HSD3B2, and CYP19A1 PII. Similarly, forskolin but not PMA, could activate all three promoters. In addition, we found that both SF1 and LRH1 can transcriptionally cooperate with the AP-1 family members c-JUN and c-FOS, known to be associated with enhanced proliferation of endometrial carcinoma cells, to further enhance activation of the STAR, HSD3B2, and CYP19A1 PII promoters. All together, our data provide novel insights into the mechanisms of steroidogenic gene expression in endometrial cancer cells and thus in the regulation of estradiol biosynthesis by tumour cells.
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PMID:The nuclear receptors SF1 and LRH1 are expressed in endometrial cancer cells and regulate steroidogenic gene transcription by cooperating with AP-1 factors. 1902 61

Endometrial cancer is the most frequent gynecological malignancy in the developed world. The majority of cases are estrogen dependent, and are associated with diminished protective effects of progesterone. Endometrial cancer is also related to enhanced inflammation and decreased differentiation. In our previous studies, we examined the expression of genes involved in estrogen and progesterone actions in inflammation and tumor differentiation, in tissue samples from endometrial cancer and adjacent control endometrium. The aims of the current study were to examine correlations between gene expression and several demographic characteristics, and to evaluate changes in gene expression with regard to histopathological and clinical characteristics of 51 patients. We studied correlations and differences in expression of 38 genes involved in five pathophysiological processes: (i) estrogen-stimulated proliferation; (ii) estrogen-dependent carcinogenesis; (iii) diminished biosynthesis of progesterone: (iv) enhanced formation of progesterone metabolites; and (v) increased inflammation and decreased differentiation. Spearman correlation coefficient analysis shows that expression of PAQR7 correlates with age, expression of SRD5A1, AKR1B1 and AKR1B10 correlate with body mass, while expression of SRD5A1 and AKR1B10 correlate with body mass index. When patients with endometrial cancer were stratified based on menopausal status, histological grade, myometrial invasion, lymphovascular invasion, and FIGO stage, Mann-Whitney U tests revealed significantly decreased expression of STAR (4.4-fold; adjusted p=0.009) and AKR1B10 (9-fold; adjusted p=0.003) in high grade versus low grade tumors. Lower levels of STAR might lead to decreased de-novo steroid hormone synthesis and tumor differentiation, and lower levels of AKR1B10 to diminished elimination of toxic electrophilic carbonyl compounds in high-grade endometrial cancer. These data thus reveal the potential of STAR and AKR1B10 as prognostic biomarkers, which calls for further validation at the protein level.
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PMID:STAR and AKR1B10 are down-regulated in high-grade endometrial cancer. 2823 77