105 resultados para Estrogen Receptor Gene


Relevância:

80.00% 80.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Nonsyndromic clefts of the lip and/or palate are common birth defects with a strong genetic component. Based on unequal gender ratios for clefting phenotypes, evidence for linkage to the X chromosome and the occurrence of several X-linked clefting syndromes, we investigated the role of skewed X chromosome inactivation (XCI) in orofacial clefts. Our samples consisted of female monozygotic (MZ) twins (n = 8) and sister pairs (n = 152) discordant for nonsyndromic clefting. We measured the XCI pattern in peripheral blood lymphocyte DNA using a methylation based androgen receptor gene assay. Skewing of XCI was defined as the deviation in inactivation pattern from a 50:50 ratio. Our analysis revealed no significant difference in the degree of skewing between twin pairs (P = 0.3). However, borderline significant differences were observed in the sister pairs (P = 0.02), with the cleft lip with cleft palate group showing the most significant result (P=0.01). We did not find evidence for involvement of skewed XCI in the discordance for clefting in our sample of female MZ twins. However, results from the paired sister study suggest the potential contribution of skewed XCI to orofacial clefting, particularly cleft lip and palate. (C) 2007 Wiley-Liss, Inc.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Endocrine system plays a major role in the control of reproductive functions which are regulated by the hypothalamus-pituitary-gonad axis and its interactions. FSH and LH receptor genes are expressed at the gonads and GnRH receptor gene is expressed at the anterior pituitary gland. Misense mutations of the FSH, LH or GnRH receptors, activating or inactivating their functions in mammals, are potentially useful to allow the understanding of the role of this group of gonadotropins in reproductive phenotypes as early puberty and birth interval length. In the present study, polymorphisms in bovine exon 11 and 3'UTR of LHR, exon 10 and 3'UTR of FSHR and GnRHR genes were characterized with some of them resulting in changes in the aminoacidic chain. These polymorphic sites were found in a Bos taurus indicus (Nellore) female population by means of PCR-SSCP and DNA sequencing. Association between nucleotidic/aminoacidic changes and early puberty were determined by Chi-square analysis. It was found association between FSHR 3'UTR polymorphisms at position 2181, 2248 and 2249 bp and early puberty phenotype (p < 0.05). The presence of these new molecular markers might be considered in further studies to validate its correlation with early puberty or other reproduction associated phenotypes in cattle breeds. (C) 2007 Published by Elsevier B.V.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Estrogen involvement in breast cancer has been established; however, the association between breast cancer and thyroid diseases is controversial. Estrogen-like effects of thyroid hormone on breast cancer cell growth in culture have been reported. The objective of the present study was to determine the profile of thyroid hormones in breast cancer patients. Serum aliquots from 26 patients with breast cancer ranging in age from 30 to 85 years and age-matched normal controls (N = 22) were analyzed for free triiodothyronine (T3F), free thyroxine (T4F), thyroid-stimulating hormone (TSH), antiperoxidase antibody (TPO), and estradiol (E2). Estrogen receptor ß (ERß) was determined in tumor tissues by immunohistochemistry. Thyroid disease incidence was higher in patients than in controls (58 vs 18%, P < 0.05). Subclinical hyperthyroidism was the most frequent disorder in patients (31%); hypothyroidism (8%) and positive anti-TPO antibodies (19%) were also found. Subclinical hypothyroidism was the only dysfunction (18%) found in controls. Hyperthyroidism was associated with postmenopausal patients, as shown by significantly higher mean T3 and T4 values and lower TSH levels in this group of breast cancer patients than in controls. The majority of positive ERß tumors were clustered in the postmenopausal patients and all cases presenting subclinical hyperthyroidism in this subgroup concomitantly exhibited Erß-positive tumors. Subclinical hyperthyroidism was present in only one of 6 premenopausal patients. We show here that postmenopausal breast cancer patients have a significantly increased thyroid hormone/E2 ratio (P < 0.05), suggesting a possible tumor growth-promoting effect caused by this misbalance.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Background. Ductal carcinoma in situ (DCIS) of the breast has been diagnosed increasingly since the advent of mammography. However, the natural history of these lesions remains uncertain. Ductal carcinoma in situ of the breast does not represent a single entity but a heterogeneous group with histologic and clinical differences. The histologic subtype of DCIS seems to have an influence on its biologic behavior, but there are few studies correlating subtype with biologic markers.Methods. The authors studied a consecutive series of 40 cases of DCIS and after its histologic categorization verified its relationship with ploidy using image analysis and analyzing estrogen receptor (ER), progesterone receptor (PR), p53 and c-erbB-2 expression using immunohistochemistry.Results. The three groups proposed according to the grade of malignancy were correlated significantly with some of the additional parameters studied, including aneuploidy and c-erB-2 expression. Aneuploidy was detected in 77.5% of cases of DCIS mainly in high and intermediate grade subtypes (100% and 80% vs. 35.7% in low grade) whereas immunoreactivity for c-erbB-2 was detected in 45% of cases of DCIS mainly in the high grade group. Expression of ER and PR were observed frequently in this study (63.9% and 65.7% respectively), but without correlation with the histologic subtype of DCIS, although we found a somewhat significant association between high grade DCIS and lack of ER. p53 protein expression was detected in 36.8% of these cases, but no relationship between this expression and histologic subtype or grading of DCIS was found.Conclusions. These results provide further evidence for the morphologic and biologic heterogeneity of DCIS. Besides histologic classification and nuclear grading, some biologic markers such as aneuploidy and c-erbB-2 expression constitute additional criteria of high grade of malignancy.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The current understanding of hormonal regulation of matrix metalloproteinase-26 (MMP-26) in the primate endometrium is incomplete. The goal of this work was to clarify estrogen and progesterone regulation of MMP-26 in the endometrium of ovariectomized, hormone-treated rhesus macaques.Ovariectomized rhesus macaques (n 66) were treated with estradiol (E-2), E-2 plus progesterone, E-2 followed by progesterone alone or no hormone. Endometrium was collected from the hormone-treated animals during the early, mid- and late proliferative and secretory phases of the artificial menstrual cycle. MMP-26 expression was quantified by real-time PCR, and MMP-26 transcript and protein were localized by in situ hybridization and immunohistochemistry and correlated with estrogen receptor 1 and progesterone receptor (PGR).MMP-26 was localized to glandular epithelium and was undetectable in the endometrial stroma and vasculature. MMP-26 transcript levels were minimal in the hormone-deprived macaques and treatment with E-2 alone did not affect MMP-26 levels. Treatment with progesterone both in the presence and absence of E-2 stimulated MMP-26 expression in the early and mid-secretory phases (P 0.001). MMP-26 expression preceded decidualization of endometrial stroma. MMP-26 levels then declined to baseline in the late secretory phase (P 0.01) despite continued E-2 plus progesterone treatment. Loss of detectable MMP-26 expression in the late secretory phase was correlated with late secretory phase loss of glandular epithelial PGR.Endometrial MMP-26 expression is dependent on the presence of progesterone in the early secretory phase and then gradually becomes refractory to progesterone stimulation in the late secretory phase. In the macaque, MMP-26 is a marker of the pre-decidual, secretory endometrium. During the second half of the late secretory phase, and during decidualization, MMP-26 loses its response to progesterone concurrent with the loss of epithelial PGR. The decline in MMP-26 levels between the mid- and late secretory phases may play a role in the receptive window for embryo implantation.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The effects of therapy in locally advanced breast cancer submitted to combined conventional telecobalt therapy plus chemotherapy with cyclophosphamide and 5-fluorouracil were studied in 49 patients. Associated to radical mastectomy in operable cases. Local tumor control was achieved in 86.7%. There were no local recurrences in those submitted to surgery but they reached 21.7% in inoperable patients who received only radiation therapy and chemotherapy. The median follow-up time for dead patients was 29.5 months and for living patients 79.3 months. The index of complete responses was 24.5% and the median disease free interval was 22.9 months. The overall survival rate, between three and five years, was 32.7%. Estrogen receptors were identified by using immunohistochemical assay ER-ICA and monoclonal antibody H222-SP gamma, Abbott. There were no differences in the complete response index, disease free interval and survival rates, among ER-positive and ER-negative patients, explained by the far advanced stage of the disease. ER-positivity was significantly correlated with histological features of the tumors: cell differentiation, presence of elastosis, absence of lymphocytic infiltration and absence of tumor necrosis.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The so-called endocrine disruptors have been described as compounds which interfere with the estrogen action in their receptors and may exert a crucial role in the development of the reproductive tract and in the brain sexual differentiation. Thus, conducts and/or exposure to these drugs in the perinatal period that apparently do not endanger the neonate may cause side effects. During embrionary development, the gonads, through discharge of a small quantity of reproductive hormones, will guarantee the phenotype of male or female at birth, as well as actuate in specific areas sexual differentiation of the central nervous system. Several experimental models have shown an interference of drugs acting as endocrine disruptors in hypothalamic sexual differentiation. Thus, reproductive function is impaired by exposure to estrogen in the perinatal life of rats and the mechanisms involved in this effect are distinct for males and females. Perinatal exposure to drugs which may be considered endocrine disrupters may induce an incomplete masculinization and defeminization of the central nervous system. Alterations in these processes, if present, generally are perceived only at puberty or adult reproductive life. These later alterations may include anomalies in the process of fertility or in sexual behavior.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

PURPOSE: to evaluate changes in mammographic breast density in postmenopausal women using raloxifene. METHODS: in this clinical trial, 80 women (mean age=61.1 years) were studied prospectively. Forty patients received 60 mg/day raloxifene, and 40 women comprised the non-treated group (control), paired by age and time of menopause. The treated group was composed of patients with osteoporosis of the lumbar spine. Those with history of breast surgery and users of hormone therapy up to six months prior to the study were excluded. The breast density was assessed qualitatively (subjective) and quantitatively (objective) in two moments, initial and final, after a 6-month follow-up. The 320 mammograms (craniocaudal and oblique) were interpreted qualitatively by the Breast Imaging Reporting and Data System (BI-RADS) classification and quantitatively by digital scanning and computer-assisted segmentation. For statistical analysis t-test, Wilcoxon Mann-Whitney, Spearman correlation and the kappa index were used. RESULTS: on the initial statistical comparison, the groups were considered homogenous for the variables: analyzed age, time of menopause, parity, breast feeding, previous hormonal therapy and body mass index. Baseline breast density, by qualitative and quantitative methods, correlated negatively with the age in both groups (p<0.05). Concerning the other variables, there was no correlation. After six months, no alteration was observed in the mammographic breast density in 38 women of raloxifene group and 38 of the control group, by qualitative method. However, by quantitative method, no alteration was observed in 30 women of the raloxifene group and 27 controls (p>0.05). It was observed a weak agreement rate (kappa=0.25) between the BI-RADS classification and digital scanning/computer-assisted segmentation. CONCLUSIONS: in post-menopausal women with osteoporosis, submitted to raloxifene treatment for six months, no alterations were observed on the mammographic breast density.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

In vertebrate species, testosterone seems to inhibit spermatogonial differentiation and proliferation. However, this androgen can also be converted, via aromatase, into estrogen which stimulates spermatogonial differentiation and mitotic activity. During seasonal spermatogenesis of adult bullfrogs Lithobates catesbeianus, primordial germ cells (PGCs) show enhanced testosterone cytoplasm immunoexpression in winter; however, in summer, weak or no testosterone immunolabelling was observed. The aim of this study was to confirm if PGCs express stem cell markers-alkaline phosphatase (AP) activity and GFRα1 (glial-cell-line-derived neurotrophic factor)-and verify whether testosterone is maintained in these cells by androgen receptors (ARs) and/or sex hormone-binding globulin (SHBG) in winter. Furthermore, regarding the possibility that testosterone is converted into estrogen by PGCs in summer, the immunoexpression of estrogen receptor (ER)β was investigated. Bullfrog testes were collected in winter and in summer and were embedded in glycol methacrylate for morphological analyses or in paraffin for the histochemical detection of AP activity. GFRα1, AR, SHBG and ERβ expression were detected by Western blot and immunohistochemical analyses. The expression of AP activity and GFRα1 in the PGCs suggest that these cells are spermatogonial stem cells. In winter, the cytoplasmic immunoexpression of ARs and SHBG in the PGCs indicates that testosterone is maintained by these proteins in these cells. The cytoplasmic immunoexpression of ERβ, in summer, also points to an ER-mediated action of estrogen in PGCs. The results indicate a participation of testosterone and estrogen in the control of the primordial spermatogonia during the seasonal spermatogenesis of L. catesbeianus. © 2012 S. Karger AG, Basel.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Aims: To evaluate the reliability of fine needle aspirate cell blocks in the assessment of oestrogen receptor (ER), progesterone receptor (PR) and HER-2/neu proteins by immunohistochemistry in comparison with surgical specimens. Materials and methods: This is a retrospective study of 62 cases of breast carcinoma diagnosed by fine needle aspiration cytology (FNAC) and confirmed using the surgical specimen. Immunohistochemical tests were performed to assess the presence of oestrogen receptor (ER), progesterone receptor (PR) and HER-2/neu proteins in cell blocks and the corresponding surgical specimens. The cell block method used alcohol prior to formalin fixation. Cases with 10% or more stained cells were considered positive for ER and PR. Positivity for HER-2/neu was assessed on a scale of 0-3+. The criterion for positivity was a score of 3+. Results: Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of the cell blocks in the investigation of ER, PR and HER-2/neu protein (3+) were (%): ER, 92.7, 85.7, 92.7, 85.7 and 90.3; PR, 92.7, 94.7, 97.4, 87.0 and 93.5; HER-2/neu, 70.0, 100.0, 100.0, 94.5 and 95.2. Discrepancies were seen in cell blocks in the 1+ and 2+ HER-2/neu staining scores: two of 12 cases scoring 2+ and one case of 26 scoring 1+ on cell blocks scored 3+ on surgical specimens. The correlation index between cell block and corresponding surgical specimen varied from 90% to 94%. Conclusion: Cell blocks provide a useful method of assessing ER, PR and HER-2/neu, mainly for inoperable and recurrent cases, but consideration should be given to carrying out FISH analysis on 1+ as well as 2+ HER-2/neu results. © 2012 Blackwell Publishing Ltd.