787 resultados para Uterine leiomyoma


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BACKGROUND: Uterine leiomyomas (fibroids) are benign smooth muscle tumors that often contain an excessive extracellular matrix (ECM). In the present study, we investigated the interactions between human uterine leiomyoma (UtLM) cells and uterine leiomyoma-derived fibroblasts (FB), and their importance in cell growth and ECM protein production using a coculture system. RESULTS: We found enhanced cell proliferation, and elevated levels of ECM collagen type I and insulin-like growth factor-binding protein-3 after coculturing. There was also increased secretion of vascular endothelial growth factor, epidermal growth factor, fibroblast growth factor-2, and platelet derived growth factor A and B in the media of UtLM cells cocultured with FB. Protein arrays revealed increased phosphorylated receptor tyrosine kinases (RTKs) of the above growth factor ligands, and immunoblots showed elevated levels of the RTK downstream effector, phospho-mitogen activated protein kinase 44/42 in cocultured UtLM cells. There was also increased secretion of transforming growth factor-beta 1 and 3, and immunoprecipitated transforming growth factor-beta receptor I from cocultured UtLM cells showed elevated phosphoserine expression. The downstream effectors phospho-small mothers against decapentaplegic -2 and -3 protein (SMAD) levels were also increased in cocultured UtLM cells. However, none of the above effects were seen in normal myometrial cells cocultured with FB. The soluble factors released by tumor-derived fibroblasts and/or UtLM cells, and activation of the growth factor receptors and their pathways stimulated the proliferation of UtLM cells and enhanced the production of ECM proteins. CONCLUSIONS: These data support the importance of interactions between fibroid tumor cells and ECM fibroblasts in vivo, and the role of growth factors, and ECM proteins in the pathogenesis of uterine fibroids.

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The Eker rat model has allowed researchers the unique opportunity to study the tumorigenesis of spontaneously occurring uterine leiomyoma. Animals in this line harbor a germline mutation in the tuberous sclerosis complex-2 (Tsc-2) tumor suppressor gene and develop uterine leiomyomas at a rate of ∼65%. Primary leiomyomas obtained from humans and Eker rats along with Eker-derived leiomyoma cell lines were used in studies described herein to determine the effect of PPARγ ligand treatment on the proliferation of this cell type and to determine the role of tuberin and p27Kip1 in the etiology of this tumor type. Treatment of leiomyoma cells of human and rat origin with PPARγ-activating compounds resulted in decreased proliferation. Additionally, PPARγ ligands inhibited estrogen-dependent gene transactivation in Eker-derived leiomyoma cells suggesting that nuclear receptor cross-talk may exist between PPAR and the ER and may be responsible for the inhibition of proliferation in this cell type. Loss of tuberin, the product of the TSC-2 gene, is associated with Eker rat leiomyoma development while the role of this tumor suppressor in human leiomyoma development is unknown. Data herein show that tuberin expression is diminished in 25% of human leiomyomas tested. Additionally, we observed diminished p27 Kip1 expression in 80% of human uterine leiomyomas compared to normal myometrium. Interestingly, the loss of tuberin expression in human leiomyoma was associated with cytoplasmic p27Kip1 accumulation in this cell type. Furthermore, tuberin-null Eker rat leiomyomas and derived cell lines had predominantly cytoplasmic p27Kip1 compared to tuberin-expressing normal myometrium. Taken together, our data show that human and Eker rat leiomyoma proliferation is inhibited upon PPARγ treatment and that the etiology of human and Eker rat leiomyoma converge at loss of p27Kip1 function. Furthermore, our data indicate that the loss of p27 Kip1 function is mediated by loss of expression (in 80% of human leiomyoma) or cytoplasmic localization potentially resulting from the loss of tuberin. ^

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Objective: In an attempt to clarify the clonality and genetic relationships that are involved in the tumorigenesis of uterine leiomyomas, we used a total of 43 multiple leiomyomas from 14 patients and analyzed the allelic status with 15 microsatellite markers and X chromosome inactivation analysis.Study design: We have used a set of 15 microsatellite polymorphism markers mapped on 3q, 7p, 11, and 15q by automated analysis. The X chromosome inactivation was evaluated by the methylation status of the X-linked androgen receptor gene.Results: Loss of heterozygosity analysis showed a different pattern in 7 of the 8 cases with allelic loss for at least 1 of 15 microsatellite markers that were analyzed. A similar loss of heterozygosity findings at 7p22-15 was detected in 3 samples from the same patient. X chromosome inactivation analysis demonstrated the same inactivated allele in all tumors of the 9 of 12 informative patients;. different inactivation patterns were observed in 3 cases.Conclusion: Our data support the concept that uterine leiomyomas are derived from a single cell but are generated independently in the uterus. Loss of heterozygosity findings at 7p22-15 are consistent with previous data that suggested the relevance of chromosomal aberrations at 7p that were involved in individual uterine leiomyomas. (C) 2005 Mosby, Inc. All rights reserved.

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Background: Uterine leiomyomas are common, benign, smooth muscle tumors representing a significant public health problem. The aim of this study was to investigate CYP17A1, CYP19, and androgen (AR) polymorphisms, their relative risks for uterine leiomyomas and possible associations with clinical parameters.Methods: Uterine leiomyoma tissues and blood samples were obtained from 87 patients, as were peripheral blood samples from 68 control women. Clinical data were recorded in both groups. The CYP17A1 (rs743572) polymorphism was analyzed by PCR-RFLP, and the CYP19 [TTTA](n) repeat and AR [CAG](n) repeat were analyzed using PCR-based GeneScan analysis. AR loss of heterozygosity (LOH) and microsatellite instability were also evaluated, while samples exhibiting LOH were analyzed for X inactivation.Results: Clinical parameters related to disease development did not differ between cases and controls. CYP17A1 *A2/*A2 genotype was prevalent in non-white women. CYP17A1, CYP19, and AR genotypes and alleles did not differ between groups. However, alleles presenting [TTTA](7) repeats in intron 4 of CYP19 were more frequent in the control group (p=0.0550). Shorter and longer [CAG]n repeat alleles of AR were exclusive to the leiomyoma group. The LOH assay showed allele losses at AR locus in four informative tumors and X chromosome inactivation analysis revealed that these tumors retained the active allele.Conclusions: The overall lack of association between uterine leiomyomas with polymorphisms involved in steroidogenesis or steroid metabolism is consistent with the hypothesis that these polymorphisms do not substantially contribute to the development of these tumors.

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Herein we report the clinical, histopathological, and molecular features of a cancer syndrome with predisposition to uterine leiomyomas and papillary renal cell carcinoma. The studied kindred included 11 family members with uterine leiomyomas and two with uterine leiomyosarcoma. Seven individuals had a history of cutaneous nodules, two of which were confirmed to be cutaneous leiomyomatosis. The four kidney cancer cases occurred in young (33- to 48-year-old) females and displayed a unique natural history. All these kidney cancers displayed a distinct papillary histology and presented as unilateral solitary lesions that had metastasized at the time of diagnosis. Genetic-marker analysis mapped the predisposition gene to chromosome 1q. Losses of the normal chromosome 1q were observed in tumors that had occurred in the kindred, including a uterine leiomyoma. Moreover, the observed histological features were used as a tool to diagnose a second kindred displaying the phenotype. We have shown that predisposition to uterine leiomyomas and papillary renal cell cancer can be inherited dominantly through the hereditary leiomyomatosis and renal cell cancer (HLRCC) gene. The HLRCC gene maps to chromosome 1q and is likely to be a tumor suppressor. Clinical, histopathological, and molecular tools are now available for accurate detection and diagnosis of this cancer syndrome.

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We describe a case of a 35-year-old woman with a pedunculated uterine leiomyoma with diffuse hydropic degeneration presenting as a giant abdominal mass. The patient was admitted in the emergency department because of diffuse abdominal bloating and discomfort. Ultrasonography (US) showed a heterogeneous abdominopelvic mass. Magnetic resonance imaging (MRI) was performed to further characterise and revealed a myometrial pedunculated tumour. Despite its marked T2-signal heterogeneity and volume, there were no other suspicious findings to suggest a malignant nature; therefore, fertility-sparing myomectomy was performed. Leiomyomas frequently undergo degenerative changes altering their imaging appearances. Leiomyomas with uncommon degenerative changes may be difficult to differentiate from malignant myometrial tumours, based solely on imaging. To the best of our knowledge, a diffuse hydropic degeneration imaging appearance has only been described twice in the literature. We describe the imaging appearance of this rare form of leio

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Dados faltantes são um problema comum em estudos epidemiológicos e, dependendo da forma como ocorrem, as estimativas dos parâmetros de interesse podem estar enviesadas. A literatura aponta algumas técnicas para se lidar com a questão, e, a imputação múltipla vem recebendo destaque nos últimos anos. Esta dissertação apresenta os resultados da utilização da imputação múltipla de dados no contexto do Estudo Pró-Saúde, um estudo longitudinal entre funcionários técnico-administrativos de uma universidade no Rio de Janeiro. No primeiro estudo, após simulação da ocorrência de dados faltantes, imputou-se a variável cor/raça das participantes, e aplicou-se um modelo de análise de sobrevivência previamente estabelecido, tendo como desfecho a história auto-relatada de miomas uterinos. Houve replicação do procedimento (100 vezes) para se determinar a distribuição dos coeficientes e erros-padrão das estimativas da variável de interesse. Apesar da natureza transversal dos dados aqui utilizados (informações da linha de base do Estudo Pró-Saúde, coletadas em 1999 e 2001), buscou-se resgatar a história do seguimento das participantes por meio de seus relatos, criando uma situação na qual a utilização do modelo de riscos proporcionais de Cox era possível. Nos cenários avaliados, a imputação demonstrou resultados satisfatórios, inclusive quando da avaliação de performance realizada. A técnica demonstrou um bom desempenho quando o mecanismo de ocorrência dos dados faltantes era do tipo MAR (Missing At Random) e o percentual de não-resposta era de 10%. Ao se imputar os dados e combinar as estimativas obtidas nos 10 bancos (m=10) gerados, o viés das estimativas era de 0,0011 para a categoria preta e 0,0015 para pardas, corroborando a eficiência da imputação neste cenário. Demais configurações também apresentaram resultados semelhantes. No segundo artigo, desenvolve-se um tutorial para aplicação da imputação múltipla em estudos epidemiológicos, que deverá facilitar a utilização da técnica por pesquisadores brasileiros ainda não familiarizados com o procedimento. São apresentados os passos básicos e decisões necessárias para se imputar um banco de dados, e um dos cenários utilizados no primeiro estudo é apresentado como exemplo de aplicação da técnica. Todas as análises foram conduzidas no programa estatístico R, versão 2.15 e os scripts utilizados são apresentados ao final do texto.

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Os tumores mistos de células musculares lisas e do estroma endometrial uterino, caracterizados pela presença de componentes de ambas as linhagens, coexistindo em proporções quase equivalentes, são neoplasmas raros. Possuem potencial biológico incerto e se comportam de acordo com o componente estromal. A imuno-histoquímica é uma grande aliada no diagnóstico microscópico, pois a clínica e os exames de imagem não ajudam a diferenciá-los de outras doenças uterinas. Descrevemos o caso de uma paciente cuja hipótese diagnóstica era de leiomioma uterino e que, após cirurgia, foi diagnosticada pelo estudo anatomopatológico como tumor misto de células musculares lisas e do estroma endometrial uterino.

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Ziel der Studie war die Untersuchung inwieweit PCNA als immunhistochemisches Hilfsmittel eine Verbesserung der Abgrenzung von uterinen LM gegenüber uterinen LMS und eine Hilfe bei der Prognoseaussage bei uterinen und gastrointestinalen LMS darstellt. Dabei wurden auch weitere, herkömmliche, in einer Reihe von Studien untersuchte Prognoseparameter mit in Betracht gezogen.rnDie Auswertung der Färbungen erfolgte quantitativ mittels einer PC-gesteuerten Bildverarbeitung, die neben der positiven Zellfläche und Zellzahl auch die Kernfläche berechnet. Vorteil der quantitativen Messung ist die Möglichkeit der Reproduzierbarkeit unabhängig vom Benutzer, im Gegensatz zu semiquantitativen Analysen, die häufiger angewendet werden.rnEs fällt dabei auf, dass sowohl die Zellkerngröße generell als auch die Zellkerngröße der positiv gefärbten Zellen signifikant größer bei LMS als bei LM ist. (p< 0,0001). Zwischen den Zellkerngrößen der uterinen und der gastrointestinalen LMS fanden sich keine signifikanten Unterschiede.rnBezüglich der Abgrenzung zwischen uterinen LM und LMS zeigten sich signifikant höhere PCNA-Meßwerte für LMS (mittlere positive Zellkernzahl 15,08%, mittlere positive Zellkernzahl 16,67%) gegenüber LM (mittlere positive Zellkernzahl 1,95%, mittlere positive Zellkernzahl 2,02%). Zu den gastrointestinalen LMS-PCNA Messwerten gab es keinen signifikanten Unterschied (mittlere positive Zellkernfläche 19,07%, mittlere positive Zellkernzahl 16,43).rnKein signifikanter Zusammenhang zeigte sich bei der Höhe der PCNA-Meßwerte und der Prognose sowohl der uterinen als auch der gastrointestinalen LMS.rnIn dieser Studie stellten sich als signifikant prognoserelevant lediglich das Alter sowohl bei den uterinen und gastrointestinalen LMS heraus. Bei den uterinen LMS war auch noch ein schlechteres Grading und das Vorhandensein von Nekrosen signifikant mit der Prognose korreliert.rnNicht signifikant prognoserelevant waren sowohl bei den uterinen wie den gastrointestinalen LMS die Tumorgröße und die PCNA-Meßwerthöhe. Bei den gastrointestinalen Leiomyosarkomen zusätzlich noch das Vorhandensein von Nekrosen.rnEin signifikanter Zusammenhang wurde zwischen PCNA-Meßwerten und der Uterusgröße bzw. auch der Myomgröße bei den uterinen Leiomyomen sowie analog der Tumorgröße der uterinen und der gastrointestinalen LMS festgestellt. Innerhalb der Gruppe der uterinen Myome zeigten sich für zellreiche Myome zwar höhere Messwerte, die jedoch nicht signifikant waren.rnKein Zusammenhang zeigte sich dagegen für die Höhe der PNCA-Meßwerte und dem Grading der uterinen sowohl als auch der gastrointestinalen Leiomyosarkome, dem Alter der Patientinnen bei den uterinen LMS, dem Vorhandensein von Nekrosen bei den uterinen sowohl als auch bei gastrointestinalen LMS und dem Geschlecht bei den gastrointestinalen LMS.rnDie Ergebnisse stehen bezüglich der Aussage der Prognose teilweise in Widerspruch, teilweise in Einklang mit den bisherigen Veröffentlichungen. Ein großes Hemmnis ist die geringe Fallzahl, die vor allem durch die Seltenheit der Tumore bedingt ist, desweiteren die ungenügende Nachverfolgung der Patienten, die auch daraus resultiert, dass es sich um eine retrospektive Studie handelt. Hier bedarf es größerer Studien, möglicherweise als multizentrische Studien mit genauer Verlaufsbeobachtung, um auch im deutschsprachigen Raum eine weitere Erforschung dieser seltenen, umsomehr sehr interessanten und an den untersuchenden Pathologen besondere Ansprüche stellende Tumore zu geben.rn

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Environmental exposures during sensitive windows of development can reprogram normal physiological responses and alter disease susceptibility later in life in a process known as developmental reprogramming. We have shown that neonatal exposure to the xenoestrogen diethylstilbestrol (DES) can developmentally reprogram the reproductive tract in genetically susceptible Eker rats giving rise to complete penetrance of uterine leiomyoma. Based on this, we hypothesized that xenoestrogens, including genistein (GEN) and bisphenol A (BPA), reprogram estrogen-responsive gene expression in the myometrium and promote the development of uterine leiomyoma. We proposed the mechanism that is responsible for the developmental reprogramming of gene expression was through estrogen (E2)/ xenoestrogen inducedrapid ER signaling, which modifies the histone methyltransferase Enhancer of Zeste homolog 2 (EZH2) via activation of the PI3K/AKT pathway. We further hypothesized that there is a xenostrogen-specific effect on this pathway altering patterns of histone modification, DNA methylation and gene expression. In addition to our novel finding that E2/DES-induced phosphorylation of EZH2 by AKT reduces the levels of H3K27me3 in vitro and in vivo, this work demonstrates in vivo that a brief neonatal exposure to GEN, in contrast to BPA, activates the PI3K/AKT pathway to regulate EZH2 and decreases H3K27me3 levels in the neonatal uterus. Given that H3K27me3 is a repressive mark that has been shown to result in DNA methylation and gene silencing we investigated the methylation of developmentally reprogrammed genes. In support of this evidence, we show that neonatal DES exposure in comparison to VEH, leads to hypomethylation of the promoter of a developmentally reprogrammed gene, Gria2, that become hyper-responsive to estrogen in the adult myometrium indicating vi that DES exposure alter gene expression via chromatin remodeling and loss of DNA methylation. In the adult uterus, GEN and BPA exposure developmentally reprogrammed expression of estrogen-responsive genes in a manner opposite of one another, correlating with our previous data. Furthermore, the ability of GEN and BPA to developmental reprogram gene expression correlated with tumor incidence and multiplicity. These data show that xenoestrogens have unique effects on the activation of non-genomic signaling in the developing uterus that promotes epigenetic and genetic alterations, which are predictive of developmental reprogramming and correlate with their ability to modulate hormone-dependent tumor development.

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Epidemiological studies have led to the hypothesis that major risk factors for developing diseases such as hypertension, cardiovascular disease and adult-onset diabetes are established during development. This developmental programming hypothesis proposes that exposure to an adverse stimulus or insult at critical, sensitive periods of development can induce permanent alterations in normal physiological processes that lead to increased disease risk later in life. For cancer, inheritance of a tumor suppressor gene defect confers a high relative risk for disease development. However, these defects are rarely 100% penetrant. Traditionally, gene-environment interactions are thought to contribute to the penetrance of tumor suppressor gene defects by facilitating or inhibiting the acquisition of additional somatic mutations required for tumorigenesis. The studies presented herein identify developmental programming as a distinctive type of gene-environment interaction that can enhance the penetrance of a tumor suppressor gene defect in adult life. Using rats predisposed to uterine leiomyoma due to a germ-line defect in one allele of the tuberous sclerosis complex 2 (Tsc-2) tumor suppressor gene, these studies show that early-life exposure to the xenoestrogen, diethylstilbestrol (DES), during development of the uterus increased tumor incidence, multiplicity and size in genetically predisposed animals, but failed to induce tumors in wild-type rats. Uterine leiomyomas are ovarian-hormone dependent tumors that develop from the uterine myometrium. DES exposure was shown to developmentally program the myometrium, causing increased expression of estrogen-responsive genes prior to the onset of tumors. Loss of function of the normal Tsc-2 allele remained the rate-limiting event for tumorigenesis; however, tumors that developed in exposed animals displayed an enhanced proliferative response to ovarian steroid hormones relative to tumors that developed in unexposed animals. Furthermore, the studies presented herein identify developmental periods during which target tissues are maximally susceptible to developmental programming. These data suggest that exposure to environmental factors during critical periods of development can permanently alter normal physiological tissue responses and thus lead to increased disease risk in genetically susceptible individuals. ^

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Exogenous ligands that bind to the estrogen receptor (ER) exhibit unique pharmacologies distinct from that observed with the endogenous hormone, 17β-estradiol (ED. Differential activity among ER ligands has been observed at the level of receptor binding, promoter interaction and transcriptional activation. Furthermore, xenoestrogens can display tissue-specific agonist activity on the cellular level, functioning as an agonist in one tissue and as an antagonist in another. That the same ligand, functioning through the same receptor, can produce differing agonist responses on the cellular level indicates that there are tissue-specific determinants of agonist activity. In these studies critical molecular determinants of agonist activity were characterized for several cell types. In the normal and neoplastic myometrium a proliferative response was dependent upon activation of AF2 of the ER, functioning as a determinant of agonism in this cell type. Progesterone receptor (PR) ligands transdominantly suppressed ER-mediated transcription and proliferation in uterine leiomyoma cells, indicating that ER/PR cross-talk can modulate agonist activity in a myometrial cell background. In the breast, the agonist response to ER ligands was investigated by employing a functional genomics approach to generate gene expression profiles. Treatment of breast cancer cells with the selective estrogen receptor modulator tamoxifen largely recapitulated the expression profile induced by treatment with the agonist E2, despite the well-characterized antiproliferative effects produced by tamoxifen in this cell type. While the expression of many genes involved in regulating cell cycle progression, including fos, myc, cdc25a, stk15 and cyclin A, were induced by both E2 and tamoxifen in breast cells, treatment with the agonist E2 specifically induced the expression of cyclin D1, fra-1 , and uracil DNA glycosylase. These results suggest that the inability of tamoxifen to transactivate expression of only a few key genes, functioning as cellular gatekeepers, prevent tamoxifen-treated breast cells from entering the cell cycle. Thus, the expression of these agonist-specific marker genes is a potential determinant of agonist activity at the cellular level in the breast. Collectively, studies in the breast and uterine myometrium have identified several mechanisms whereby ER ligands modulate ER-mediated signaling and provide insights into the biology of tissue-specific agonist activity in hormone-responsive tissues. ^

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Introduction. Cystadenofibromas of the Fallopian tube are very rare benign tumors of the female genital tract. These tumours are usually asymptomatic and are found incidentally. Case report. We describe a Fallopian serous cystadenofibroma in a 50 year-old woman operated for uterine leiomyoma. The histopathologic finding revealed a cystic lesion connected to the salpinx. The cyst was composed of connective stroma lined by epithelial cuboidal cells, without pleomorfism or detectable mitoses. Pseudopapillary structures were observed in the lumen of the cyst. The patient is well on follow-up. Conclusion. The origin of serous cystadenofibroma of the Fallopian tube is not clear. The tumor is considered an embryologic remnant rather than a proliferating neoplastic process. These tumours seem to have a benign course and a malignant potential has not been described.

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Uterine leiomyomata (UL), the most prevalent pelvic tumors in women of reproductive age, pose a major public health problem given their high frequency, associated morbidities, and most common indication for hysterectomies. A genetic component to UL predisposition is supported by analyses of ethnic predisposition, twin studies, and familial aggregation. A genome-wide SNP linkage panel was genotyped and analyzed in 261 white UL-affected sister-pair families from the Finding Genes for Fibroids study. Two significant linkage regions were detected in 10p11 (LOD = 4.15) and 3p21 (LOD = 3.73), and five additional linkage regions were identified with LOD scores > 2.00 in 2q37, 5p13, 11p15, 12q14, and 17q25. Genome-wide association studies were performed in two independent cohorts of white women, and a meta-analysis was conducted. One SNP (rs4247357) was identified with a p value (p = 3.05 x 10(-8)) that reached genome-wide significance (odds ratio = 1.299). The candidate SNP is under a linkage peak and in a block of linkage disequilibrium in 17q25.3, which spans fatty acid synthase (FASN), coiled-coil-domain-containing 57 (CCDC57), and solute-carrier family 16, member 3 (SLC16A3). By tissue microarray immunohistochemistry, we found elevated (3-fold) FAS levels in UL-affected tissue compared to matched myometrial tissue. FAS transcripts and/or protein levels are upregulated in various neoplasms and implicated in tumor cell survival. FASN represents the initial UL risk allele identified in white women by a genome-wide, unbiased approach and opens a path to management and potential therapeutic intervention.