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1.
Mol Cancer Res ; 21(10): 1023-1036, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37363949

RESUMO

Activating estrogen receptor alpha (ER; also known as ESR1) mutations are present in primary endometrial and metastatic breast cancers, promoting estrogen-independent activation of the receptor. Functional characterizations in breast cancer have established unique molecular and phenotypic consequences of the receptor, yet the impact of ER mutations in endometrial cancer has not been fully explored. In this study, we used CRISPR-Cas9 to model the clinically prevalent ER-Y537S mutation and compared results with ER-D538G to discover allele-specific differences between ER mutations in endometrial cancer. We found that constitutive activity of mutant ER resulted in changes in the expression of thousands of genes, stemming from combined alterations to ER binding and chromatin accessibility. The unique gene expression programs resulted in ER-mutant cells developing increased cancer-associated phenotypes, including migration, invasion, anchorage-independent growth, and growth in vivo. To uncover potential treatment strategies, we identified ER-associated proteins via Rapid Immunoprecipitation and Mass Spectrometry of Endogenous Proteins and interrogated two candidates, CDK9 and NCOA3. Inhibition of these regulatory proteins resulted in decreased growth and migration, representing potential novel treatment strategies for ER-mutant endometrial cancer. IMPLICATIONS: This study provides insight into mutant ER activity in endometrial cancer and identifies potential therapies for women with ER-mutant endometrial cancer.


Assuntos
Neoplasias da Mama , Neoplasias do Endométrio , Feminino , Humanos , Alelos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Neoplasias da Mama/patologia , Mutação , Neoplasias do Endométrio/genética , Fenótipo
2.
Cancer Res ; 80(6): 1234-1245, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32046982

RESUMO

Estrogen signaling through estrogen receptor alpha (ER) plays a major role in endometrial cancer risk and progression, however, the molecular mechanisms underlying ER's regulatory role in endometrial cancer are poorly understood. In breast cancer cells, ER genomic binding is enabled by FOXA1 and GATA3, but the transcription factors that control ER genomic binding in endometrial cancer cells remain unknown. We previously identified ETV4 as a candidate factor controlling ER genomic binding in endometrial cancer cells, and here we explore the functional importance of ETV4. Homozygous deletion of ETV4, using CRISPR/Cas9, led to greatly reduced ER binding at the majority of loci normally bound by ER. Consistent with the dramatic loss of ER binding, the gene expression response to estradiol was dampened for most genes. ETV4 contributes to estrogen signaling in two distinct ways. ETV4 loss affects chromatin accessibility at some ER bound loci and impairs ER nuclear translocation. The diminished estrogen signaling upon ETV4 deletion led to decreased growth, particularly in 3D culture, where hollow organoids were formed and in vivo in the context of estrogen-dependent growth. These results show that ETV4 plays an important role in estrogen signaling in endometrial cancer cells. SIGNIFICANCE: Estrogen receptor alpha (ER) is a key oncogene in endometrial cancer. This study uncovers ETV4 as an important factor in controlling the activity of ER and the growth of endometrial cancer cells. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/6/1234/F1.large.jpg.


Assuntos
Neoplasias do Endométrio/genética , Receptor alfa de Estrogênio/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-ets/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Citoplasma/metabolismo , Neoplasias do Endométrio/patologia , Estradiol/metabolismo , Feminino , Técnicas de Inativação de Genes , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-ets/genética , RNA-Seq , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Rev. cientif. cienc. med ; 23(1): 15-21, 2020. ilus
Artigo em Espanhol | LILACS | ID: biblio-1126274

RESUMO

INTRODUCCIÓN: el uso de plantas con diversos fines etnomedicinales es una práctica ancestral y actualmente común en una vasta parte de la población de Bolivia. OBJETIVO GENERAL: identificar si la wira wira y cerraja de nuestro medio poseen actividad antimicrobiana contra bacterias patógenas y determinar su toxicidad a través del bioensayo de pruebas biológicas. MATERIALES Y MÉTODOS: estudio descriptivo; Universo, Wira Wira recolectada del Valle Alto de Cochabamba y Cerraja de Cercado; Muestra, se obtuvo de forma aleatoria un kilogramo de Wira Wira y Cerraja respectivamente; Métodos, se emplearon diferentes técnicas para la extracción de los principios activos, se realizaron pruebas biológicas para determinar la toxicidad de los mismos y se determinó la actividad antimicrobiana por el método de difusión en agar. RESULTADOS: Wira wira demostró actividad antimicrobiana con 4 extractos; alcohólico de tallo, flor y alcohólico agotado de hojas frente a E. faecalis y S. aureus, y acuoso de hojas frente a P. aeruginosa y S. aureus. Por otro lado no se evidencio actividad antibacteriana de los extractos de cerraja. CONCLUSIONES: Wira wira es candidata para estudios posteriores destinados a la identificación del o los compuestos activos puros con actividad antibacteriana, hecho respaldado por los resultados obtenidos en esta y otras investigaciones. Los extractos de cerraja, a diferencia de los resultados obtenidos de otros trabajos, no presentaron actividad antimicrobiana, demostrando la posibilidad y vinculación de la variación en los compuestos de la planta con el ecosistema en el que se desarrolla.(AU)


INTRODUCTION: the use of plants with various ethnomedicinal purposes is an ancestral practice and currently common in a vast part of the population of Bolivia. GENERAL OBJECTIVE: to identify if the extracts of both plants present in our environment have antimicrobial activity against pathogenic bacteria and to determine their toxicity through the bioassay of biological tests. MATERIALS AND METHODS: descriptive study; Universe, Wira Wira collected from Valle Alto in Cochabamba and Cerraja collected from Cercado; Sample, we obtained one kilogram of each, Wira Wira and Cerraja randomly; Methods, different techniques were used to extract the active ingredients, biological tests were performed to determine their toxicity and antimicrobial activity was determined by the agar diffusion method. RESULTS: Wira Wira demonstrated antimicrobial activity with 4 extracts; stem alcoholic, flower and alcoholic depleted of leaves against E. faecalis and S. aureus, and aqueous of leaves against P. aeruginosa and S. aureus. On the other hand, there was no evidence of antibacterial activity with the cerraja extracts. CONCLUSIONS: Wira Wira is a candidate for further studies aimed at the identification of the pure active compound (s) with antibacterial activity, all this backed up by the positive results in the agar diffusion tests grown with pathogenic bacteria. Unlike the results that demonstrate the antibacterial activity of the Cerraja in research carried out in other parts of the world, it is not the case of the one in our territory, whose extracts did not present any antimicrobial activity, demonstrating the possibility and linking the variation in plant compounds with the ecosystems in which it develops.


Assuntos
Antibacterianos , Plantas , Extratos Vegetais , Achyrocline
4.
Life Sci Alliance ; 2(5)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31570515

RESUMO

Multiple regulatory regions bound by the same transcription factor have been shown to simultaneously control a single gene's expression. However, it remains unclear how these regulatory regions combine to regulate transcription. Here, we test the sufficiency of promoter-distal estrogen receptor α-binding sites (ERBSs) for activating gene expression by recruiting synthetic activators in the absence of estrogens. Targeting either dCas9-VP16(10x) or dCas9-p300(core) to ERBS induces H3K27ac and activates nearby expression in a manner similar to an estrogen induction, with dCas9-VP16(10x) acting as a stronger activator. The sufficiency of individual ERBSs is highly correlated with their necessity, indicating an inherent activation potential that is associated with the binding of RNA polymerase II and several transcription factors. By targeting ERBS combinations, we found that ERBSs work independently to control gene expression when bound by synthetic activators. The sufficiency results contrast necessity assays that show synergy between these ERBSs, suggesting that synergy occurs between ERBSs in terms of activator recruitment, whereas directly recruiting activators leads to independent effects on gene expression.


Assuntos
Elementos Facilitadores Genéticos/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Ativação Transcricional/efeitos dos fármacos , Sítios de Ligação , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Estrogênios/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos
5.
Horm Cancer ; 10(2-3): 51-63, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30712080

RESUMO

Endometrial cancer is the most common gynecological cancer in the developed world, and it is one of the few cancer types that is becoming more prevalent and leading to more deaths in the USA each year. The majority of endometrial tumors are considered to be hormonally driven, where estrogen signaling through estrogen receptor α (ER) acts as an oncogenic signal. The major risk factors and some treatment options for endometrial cancer patients emphasize a key role for estrogen signaling in the disease. Despite the strong connections between estrogen signaling and endometrial cancer, important molecular aspects of ER function remain poorly understood; however, progress is being made in our understanding of estrogen signaling in endometrial cancer. Here, we discuss the evidence for the importance of estrogen signaling in endometrial cancer, details of the endometrial cancer-specific actions of ER, and open questions surrounding estrogen signaling in endometrial cancer.


Assuntos
Neoplasias do Endométrio/metabolismo , Estrogênios/metabolismo , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Progesterona/metabolismo , Fatores de Risco , Esteroides/metabolismo , Transcrição Gênica
6.
Cell Rep ; 22(11): 2995-3005, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29539426

RESUMO

Steroid hormone receptors are simultaneously active in many tissues and are capable of altering each other's function. Estrogen receptor α (ER) and glucocorticoid receptor (GR) are expressed in the uterus, and their ligands have opposing effects on uterine growth. In endometrial tumors with high ER expression, we surprisingly found that expression of GR is associated with poor prognosis. Dexamethasone reduced normal uterine growth in vivo; however, this growth inhibition was abolished in estrogen-induced endometrial hyperplasia. We observed low genomic-binding site overlap when ER and GR are induced with their respective ligands; however, upon simultaneous induction they co-occupy more sites. GR binding is altered significantly by estradiol with GR recruited to ER-bound loci that become more accessible upon estradiol induction. Gene expression responses to co-treatment were more similar to estradiol but with additional regulated genes. Our results suggest phenotypic and molecular interplay between ER and GR in endometrial cancer.


Assuntos
Neoplasias do Endométrio/genética , Genômica/métodos , Receptores de Glucocorticoides/genética , Neoplasias do Endométrio/patologia , Feminino , Humanos
7.
Gac. méd. boliv ; 30(2): 11-14, 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-737760

RESUMO

La toxoplasmosis es una enfermedad causada por el parásito Toxoplasma gondii, capaz de transmitirse al feto con graves consecuencias. Para el diagnóstico de toxoplasmosis se detectan inmunoglobulinas G (IgG) y M (IgM). Debido a que por ELISA se obtiene un número excesivo de falsos positivos y negativos, en el Hospital Elizabeth Seton evaluamos la utilidad de los reactivos de ELISA para la detección de IgG e IgM frente a Toxoplasma gondii empleando como referencia la inmnofluorescencia (IF) . Mediante ELISA e IF se determinó IgG en 146 e IgM en 142 sueros obtenidos de mujeres en edad fértil y embarazadas y niños atendidos de junio de 2004 a octubre de 2005 en la Caja Petrolera de Salud. Con los resultados obtenidos se determinó la sensibilidad, especificidad, valor predictivo positivo (VPP) y negativo (VPN) de la técnica de ELISA. La técnica de ELISA para IgG tiene sensibilidad: 75 %; especificidad: 84%; VPP 64%: VPN 90 %. Por ELISA no se detectó anticuerpos en un 25 % de pacientes infectados y 16 % eran falsos positivos; hay un 64% de probabilidad de que individuos con resultado positivo estén realmente afectados por la infección, y un 90% de probabilidad de que sujetos con seronegatividad sean realmente seronegativos. Para la IgM, ELISA tiene sensibilidad 40 %; Especificidad 96%; VPP 71%; VPN 88 %. Vale decir por ELISA no se detectaron 60% de infectados; y 4% resultaron falsos positivos; hay un 71% de probabilidad de que el paciente este realmente afectado y un 88 % de probabilidad de que sea realmente seronegativo Por lo tanto la técnica de ELISA tiene muy baja sensibilidad principalmente para IgM, parámetro que junto con la especificidad, VPP y VPN, deben considerarse al tiempo de hacer la interpretación de laboratorio y diagnóstico clínico.


The toxoplasmosis is an illness caused by the parasite Toxoplasma gondii, able to be transmitted to the fetus with serious consequences. For the toxoplasmosis diagnosis it is necessary to detect inmunoglobuline G (IgG) and M (IgM). Because ELISA gives an excessive number of false positive and false negative, we evaluate the utility of ELISA reagents for IgG and IgM detection at Hospital Elizabeth Seton in order to compare with Toxoplasma gondii inmnofluorescencia (IF) method used as reference. IgG (146 patients) and IGM (142 patients) were determined by ELISA and IF on serums from fertile age and pregnant women, and children consulted from June 2004 to October 2005 at Caja Petrolera de Salud. Sensibility, specificity and the predictive positive (VPP) and negtive (VPN) values were determined for ELISA technique. ELISA sensibility for IgG is 75%; specificicity 84%, VPP 64%; VPN, 90%. By ELISA it were not detected antibodies in 25 % of infeted patients and in 16% they were false positive; there is 64% of probability that individuals with positive result been really affected by the infection and 90% of probability that subject with seronegativity been really seronegative. For the IgM; ELISA has sensibility of 40%, specificity of 96%, VPP, 71%, and VPN, 88%. That means that ELISA was not able to detect 60% of infected, and in 4% it was false positive; there was 71% of probability that the patient be really affected and 88% of probability that it be really seronegative. Therefore, the ELISA technique has very low sensibility mainly for IgM, parameter that together with the specificity, VPP and VPN, should be taken on count at the time of do the laboratory interpretation and clinical diagnostic.


Assuntos
Toxoplasmose
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