RESUMO
Las enfermedades causadas por amebas de vida libre son infecciones oportunistas que pueden tener un curso fatal. Pueden producir afecciones diseminadas graves con compromiso del sistema nervioso central, como la encefalitis amebiana granulomatosa. Esta infección es cada vez más frecuente en América Latina, aunque se reconocen tardíamente debido a la similitud con otras patologías o porque es inusual incluirla en el diagnóstico diferencial. Comunicamos un caso fatal de una encefalitis amebiana granulomatosa por Balamuthia mandrillaris en una niña de 10 años. Destacamos la gravedad de la afectación cerebral y la falta de esquemas antimicrobianos validados para su tratamiento. Hoy en el mundo esta infección es considerada una enfermedad emergente, influenciada por el cambio climático, lo que llama a estar atentos a su presencia.
Diseases caused by free-living amoebae are opportunistic infections that can have a fatal course. They can cause very serious disseminated conditions with involvement of the central nervous system such as granulomatous amoebic encephalitis. This infection has become more common in Latin America, although its recognition is late due to the similarity with other pathological conditions or because it is unusual to include it in the differential diagnosis. We report a fatal case of granulomatous amoebic encephalitis due to Balamuthia mandrillaris in a 10-year-old girl. We highlight the severity of the brain involvement and the lack of validated schemes for its treatment. Today in the world this infection is considered an emerging disease, influenced by climate change, which calls for being attentive to its presence.
Assuntos
Humanos , Feminino , Criança , Encefalite Infecciosa/diagnóstico , Amebíase/diagnóstico , Tomografia Computadorizada por Raios X , Análise de Sequência de DNA , Evolução Fatal , Balamuthia mandrillaris/isolamento & purificação , Balamuthia mandrillaris/genética , Encefalite Infecciosa/diagnóstico por imagem , Amebíase/diagnóstico por imagemRESUMO
Resumen La Sociedad Chilena de Infectología, a través de su Comité de Infecciones Neonatales, en conjunto con la Sociedad Chilena de Obstetricia y Ginecología, proponen un documento de diagnóstico y manejo de la Infección por Citomegalovirus en la Mujer Embarazada y el Recién Nacido. Esta guía aborda el manejo de la infección en el binomio, su enfrentamiento diagnóstico y terapéutico, orientado al equipo de salud que atiende a mujeres embarazadas y recién nacidos con infección por citomegalovirus (CMV) en Chile. Considera la situación epidemiológica global y latinoamericana, con recomendaciones para la evaluación clínica y de laboratorio; establece criterios de diagnóstico, propone enfoques terapéuticos de acuerdo a la situación clínica, analiza las medidas de prevención y establece una propuesta nacional para el seguimiento de esta enfermedad. Se ha puesto especial énfasis en entregar, de forma práctica, y con la mayor evidencia posible, las recomendaciones para el manejo del binomio con infección por CMV.
Abstract The Chilean Society of Infectology, through its Neonatal Infections Committee in conjunction with the Chilean Society of Obstetrics and Gynecology, propose a document for the Diagnosis and Management of Cytomegalovirus Infection in Pregnant Woman and Newborn Infant. This guideline suggests the management of mother and child infection, its diagnostic and therapeutic options. Considers the global and Latin American epidemiology, with recommendations for clinical and laboratory evaluation; diagnostic criteria, therapeutic approaches according to the clinical situation, analyzes prevention measures and establishes a national proposal for monitoring this disease.
Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Lactente , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/transmissão , Chile , Gestantes , GinecologiaRESUMO
Resumen La Sociedad Chilena de Infectología, a través de su Comité de Infecciones Neonatales, en conjunto con la Sociedad Chilena de Obstetricia y Ginecología, proponen un documento de diagnóstico y manejo de la infección por citomegalovirus (CMV) en la mujer embarazada y el recién nacido. Esta guía aborda el manejo de la infección en el binomio, su enfrentamiento diagnóstico y terapéutico, orientado al equipo de salud que atiende a mujeres embarazadas y recién nacidos con infección por CMV en Chile. Considera la situación epidemiológica global y latinoamericana, con recomendaciones para la evaluación clínica y de laboratorio; establece criterios de diagnóstico, propone enfoques terapéuticos de acuerdo a la situación clínica, analiza las medidas de prevención y establece una propuesta nacional para el seguimiento de esta enfermedad. Se ha puesto especial énfasis en entregar, de forma práctica, y con la mayor evidencia posible, las recomendaciones para el manejo del binomio con infección por CMV.
Abstract The Chilean Society of Infectology, through its Neonatal Infections Committee in conjunction with the Chilean Society of Obstetrics and Gynecology, propose a document for the Diagnosis and Management of Cytomegalovirus Infection in Pregnancy and Newborn. This guideline suggests the management of mother and child infection, its diagnostic and therapeutic options. Considers the global and Latin American epidemiology, with recommendations for clinical and laboratory evaluation, diagnostic criteria, therapeutic approaches according to the clinical situation, analyzes prevention measures and establishes a national proposal for monitoring this disease.
Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/terapia , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/terapia , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/terapia , Diagnóstico Pré-Natal , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/terapia , Infecções por Citomegalovirus/congênitoRESUMO
Clinical studies have suggested a survival benefit in ovarian cancer patients with type 2 diabetes mellitus taking metformin, however the mechanism by which diabetic concentrations of metformin could deliver this effect is still poorly understood. Platelets not only represent an important reservoir of growth factors and angiogenic regulators, they are also known to participate in the tumor microenvironment implicated in tumor growth and dissemination. Herein, we investigated if diabetic concentrations of metformin could impinge upon the previously reported observation that platelet induces an increase in the tube forming capacity of endothelial cells (angiogenesis) and upon ovarian cancer cell aggressiveness. We demonstrate that metformin inhibits the increase in angiogenesis brought about by platelets in a mechanism that did not alter endothelial cell migration. In ovarian cancer cell lines and primary cultured cancer cells isolated from the ascitic fluid of ovarian cancer patients, we assessed the effect of combinations of platelets and metformin upon angiogenesis, migration, invasion and cancer sphere formation. The enhancement of each of these parameters by platelets was abrogated by the present of metformin in the vast majority of cancer cell cultures tested. Neither metformin nor platelets altered proliferation; however, metformin inhibited the increase in phosphorylation of focal adhesion kinase induced by platelets. We present the first evidence suggesting that concentrations of metformin present in diabetic patients may reduce the actions of platelets upon both endothelial cells and cancer cell survival and dissemination.
Assuntos
Plaquetas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Progressão da Doença , Feminino , Humanos , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/patologia , Células Tumorais CultivadasRESUMO
BACKGROUND: An increase in circulating platelets, or thrombocytosis, is recognized as an independent risk factor of bad prognosis and metastasis in patients with ovarian cancer; however the complex role of platelets in tumor progression has not been fully elucidated. Platelet activation has been associated with an epithelial to mesenchymal transition (EMT), while Tissue Factor (TF) protein expression by cancer cells has been shown to correlate with hypercoagulable state and metastasis. The aim of this work was to determine the effect of platelet-cancer cell interaction on TF and "Metastasis Initiating Cell (MIC)" marker levels and migration in ovarian cancer cell lines and cancer cells isolated from the ascetic fluid of ovarian cancer patients. METHODS: With informed patient consent, ascitic fluid isolated ovarian cancer cells, cell lines and ovarian cancer spheres were co-cultivated with human platelets. TF, EMT and stem cell marker levels were determined by Western blotting, flow cytometry and RT-PCR. Cancer cell migration was determined by Boyden chambers and the scratch assay. RESULTS: The co-culture of patient-derived ovarian cancer cells with platelets causes: 1) a phenotypic change in cancer cells, 2) chemoattraction and cancer cell migration, 3) induced MIC markers (EMT/stemness), 3) increased sphere formation and 4) increased TF protein levels and activity. CONCLUSIONS: We present the first evidence that platelets act as chemoattractants to cancer cells. Furthermore, platelets promote the formation of ovarian cancer spheres that express MIC markers and the metastatic protein TF. Our results suggest that platelet-cancer cell interaction plays a role in the formation of metastatic foci.
Assuntos
Plaquetas/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Tromboplastina/metabolismo , Biomarcadores , Comunicação Celular , Movimento Celular , Fatores Quimiotáticos/metabolismo , Feminino , Humanos , Estadiamento de Neoplasias , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/cirurgia , Fenótipo , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Tromboplastina/genética , Células Tumorais CultivadasRESUMO
To characterize the molecular mechanism and map the response element used by progesterone (P) to upregulate tissue factor (TF) in breast cancer cells. TF expression and mRNA levels were analyzed in breast cancer ZR-75 and T47D cells, using Western blot and real-time PCR, respectively. Mapping of the TF promoter was performed using luciferase vectors. Progesterone receptor (PR) and specificity protein 1 (Sp1) binding to the TF promoter were analyzed by chromatin immuno precipitation assay. Specific or selective inhibitors were used for the MEK1/2 and the c-Src pathways (UO126 and PP2, respectively). TF mRNA increase peaks at 18 h following P treatment in ZR-75 and T47D cells. P upregulation occurs via a transcriptional mechanism that depends on PR and MEK1/2 activation, PR and Sp1 transcription factors bind to a region in the TF promoter that contains three Sp1 sites. TF mRNA upregulation requires an intact PR proline-rich site (mPRO), but it is independent from c-Src. TF upregulation by P is mediated by Sp1 sites in the TF promoter region. Transcriptional upregulation in breast cancer cells occurs via a new mechanism that requires MEK1/2 activation and the mPRO site but independent of c-Src activity. PR Phosphorylation at serine 294 and 345 is not essential.
Assuntos
Sistema de Sinalização das MAP Quinases/fisiologia , Progesterona/fisiologia , Prolina/fisiologia , Receptores de Progesterona/fisiologia , Tromboplastina/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Genes src/genética , Humanos , Fosforilação , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Regulação para Cima/fisiologiaRESUMO
Knockout models have shown that the coagulation system has a role in vascular development and angiogenesis. Herein, we report for the first time that zymogen FX and its active form (FXa) possess anti-angiogenic properties. Both the recombinant FX and FXa inhibit angiogenesis in vitro using endothelial EA.hy926 and human umbilical cord vascular endothelial cells (HUVEC). This effect is dependent on the Gla domain of FX. We demonstrate that FX and FXa use different mechanisms: the use of Rivaroxaban (RX) a specific inhibitor of FXa attenuated its anti-angiogenic properties but did not modify the anti-angiogenic effect of FX. Furthermore, only the anti-angiogenic activity of FXa is PAR-1dependent. Using in vivo models, we show that FX and FXa are anti-angiogenic in the zebrafish intersegmental vasculature (ISV) formation and in the chick embryo chorioallantoic membrane (CAM) assays. Our results provide further evidence for the non-hemostatic functions of FX and FXa and demonstrate for the first time a biological role for the zymogen FX.
Assuntos
Inibidores da Angiogênese/farmacologia , Fator Xa/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Embrião de Galinha , Fator X/farmacologia , Fator X/uso terapêutico , Fator Xa/uso terapêutico , Proteínas de Helminto/farmacologia , Proteínas de Helminto/uso terapêutico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Receptor PAR-1/metabolismo , Peixe-ZebraRESUMO
Our laboratory has implemented an in vitro assay to estimate the response to chemotherapy in ovarian cancer cells pertaining to individual patients. In two selected patients, we determined the correlation between an in vitro assay of cells from suspected ovarian cancer ascites, with the clinical chemotherapy response. Cancer cells isolated from peritoneal fluid with suspected ovarian cancer were tested for cytotoxicity with corresponding chemotherapy regimens. Circulating Cal25 levels and attending physician consultation determined clinical course and response to chemotherapy. The in vitro assay result correlated with Cal25 levels, progression free survival and attending physician evaluation. The assay predicted correctly the failure of two successive chemotherapy regimes in the first patient, while predicting a favorable clinical response in the second subject.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/análise , Antígeno Ca-125/análise , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Ovarianas/sangue , Medicina de Precisão , Indução de Remissão , Células Tumorais CultivadasRESUMO
The use of the type 2 diabetics drug metformin has been correlated with enhanced progression-free survival in ovarian cancer. The literature has speculated that this enhancement is due to the high concentration of metformin directly causing cancer cell death. However, this explanation does not fit with clinical data reporting that the women exposed to constant micromolar concentrations of metformin, as present in the treatment of diabetes, respond better to chemotherapy. Herein, our aim was to examine whether micromolar concentrations of metformin alone could bring about cancer cell death and whether micromolar metformin could increase the cytotoxic effect of commonly used chemotherapies in A2780 and SKOV3 cell lines and primary cultured cancer cells isolated from the peritoneal fluid of patients with advanced ovarian cancer. Our results in cell lines demonstrate that no significant loss of viability or change in cell cycle was observed with micromolar metformin alone; however, we observed cytotoxicity with micromolar metformin in combination with chemotherapy at concentrations where the chemotherapy alone produced no loss in viability. We demonstrate that previous exposure and maintenance of metformin in conjunction with carboplatin produces a synergistic enhancement in cytotoxicity of A2780 and SKOV3 cells (55% and 43%, respectively). Furthermore, in 5 (44%) of the 11 ovarian cancer primary cultures, micromolar metformin improved the cytotoxic response to carboplatin but not paclitaxel or doxorubicin. In conclusion, we present data that support the need for a clinical study to evaluate the adjuvant maintenance or prescription of currently approved doses of metformin during the chemotherapeutic treatment of ovarian cancer.
Assuntos
Antineoplásicos/farmacologia , Carboplatina/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Neoplasias Ovarianas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Humanos , Fatores de Tempo , Células Tumorais CultivadasRESUMO
Our laboratory has implemented an in vitro assay to estimate the response to chemotherapy in ovarian cancer cells pertaining to individual patients. In two selected patients, we determined the correlation between an in vitro assay of cells from suspected ovarian cancer ascites, with the clinical chemotherapy response. Cancer cells isolated from peritoneal fluid with suspected ovarian cancer were tested for cytotoxicity with corresponding chemotherapy regimens. Circulating Cal25 levels and attending physician consultation determined clinical course and response to chemotherapy. The in vitro assay result correlated with Cal25 levels, progression free survival and attending physician evaluation. The assay predicted correctly the failure of two successive chemotherapy regimes in the first patient, while predicting a favorable clinical response in the second subject.
Assuntos
Adulto , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , /análise , Intervalo Livre de Doença , Medicina de Precisão , Neoplasias Ovarianas/sangue , Indução de Remissão , Células Tumorais Cultivadas , Biomarcadores Tumorais/análiseRESUMO
Reproductive success stems from a finely regulated balance between follicular maturation and atresia, in which the role of carbohydrate structure is poorly understood. Here, we describe for the first time a fraction of purified recombinant human FSH that is capable of bringing about the cell death of granulosa cells and preventing follicular maturation in a rat model. Further analysis by mass spectrometry revealed the presence of the lectin Concanavalin-A (Con-A) within this fraction of recombinant FSH. Using both the fractionated FSH and Con-A, the observed cell death was predominantly located to the granulosa cells. Ex vivo culture of rat follicles demonstrated that follicle degeneration occurred and resulted in the release of a denuded and deteriorated oocyte. Moreover, in vivo experiments confirmed an increase in atresia and a corresponding reduction confined to follicle in early antral stage. As a mechanism of action, Con-A reduces ovarian proliferation, Von Willebrand staining, and angiogenesis. Based on the observation that Con-A may induce granulosa cell death followed by follicle death, our results further demonstrate that follicular carbohydrate moiety is changing under the influence of FSH, which may allow a carbohydrate-binding lectin to increase granulosa cell death. The physiological consequences of circulating lectin-like molecules remain to be determined. However, our results suggest a potential exploitation of carbohydrate binding in fertility and ovarian cancer treatment. This work may shed light on a key role of carbohydrates in the still obscure physiological process of follicular selection and atresia.
Assuntos
Concanavalina A/farmacologia , Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Células da Granulosa/fisiologia , Mitógenos/farmacologia , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/fisiologia , Ovário/crescimento & desenvolvimento , Ovário/fisiologia , Ratos , Ratos Sprague-DawleyRESUMO
2-Methoxyestradiol (2ME), an endogenous metabolite of 17ß-estradiol, has been previously reported to possess antiangiogenic and antitumor properties. Herein, we demonstrate that the effects of this antiangiogenic steroid can be readily assayed in live zebrafish, introducing a convenient and robust new model system as a screening tool for both single cell and collective cell migration assays. Using the in vitro mammalian endothelial cell line EA.hy926, we first show that cell migration and angiogenesis, as estimated by wound assay and tube formation respectively, are antagonized by 2ME. In zebrafish (Danio rerio) larvae, dose-dependent exposure to 2ME diminishes (1) larval angiogenesis, (2) leukocyte recruitment to damaged lateral line neuromasts and (3) retards the lateral line primordium in its migration along the body. Our results indicate that 2ME has an effect on collective cell migration in vivo as well as previously reported anti-tumorigenic activity and suggests that the molecular mechanisms governing cell migration in a variety of contexts are conserved between fish and mammals. Moreover, we exemplify the versatility of the zebrafish larvae for testing diverse physiological processes and screening for antiangiogenic and antimigratory drugs in vivo.
Assuntos
Inibidores da Angiogênese/farmacologia , Anti-Inflamatórios/farmacologia , Movimento Celular/efeitos dos fármacos , Estradiol/análogos & derivados , 2-Metoxiestradiol , Animais , Animais Geneticamente Modificados , Linhagem Celular , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Larva/genética , Larva/metabolismo , Larva/fisiologia , Microscopia de Fluorescência , Neovascularização Fisiológica/efeitos dos fármacos , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologiaRESUMO
Progesterone and progestins have been demonstrated to enhance breast cancer cell migration, although the mechanisms are still not fully understood. The protease-activated receptors (PARs) are a family of membrane receptors that are activated by serine proteases in the blood coagulation cascade. PAR1 (F2R) has been reported to be involved in cancer cell migration and overexpressed in breast cancer. We herein demonstrate that PAR1 mRNA and protein are upregulated by progesterone treatment of the breast cancer cell lines ZR-75 and T47D. This regulation is dependent on the progesterone receptor (PR) but does not require PR phosphorylation at serine 294 or the PR proline-rich region mPRO. The increase in PAR1 mRNA was transient, being present at 3â h and returning to basal levels at 18 âh. The addition of a PAR1-activating peptide (aPAR1) to cells treated with progesterone resulted in an increase in focal adhesion (FA) formation as measured by the cellular levels of phosphorylated FA kinase. The combined but not individual treatment of progesterone and aPAR1 also markedly increased stress fiber formation and the migratory capacity of breast cancer cells. In agreement with in vitro findings, data mining from the Oncomine platform revealed that PAR1 expression was significantly upregulated in PR-positive breast tumors. Our observation that PAR1 expression and signal transduction are modulated by progesterone provides new insight into how the progestin component in hormone therapies increases the risk of breast cancer in postmenopausal women.
Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Movimento Celular/efeitos dos fármacos , Adesões Focais/efeitos dos fármacos , Progesterona/farmacologia , Receptor PAR-1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Avaliação Pré-Clínica de Medicamentos , Feminino , Adesões Focais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes erbB-1/fisiologia , Humanos , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 1/fisiologia , Pós-Menopausa/genética , Pós-Menopausa/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/fisiologia , Receptor PAR-1/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genéticaRESUMO
Tissue factor (TF) serving as the receptor for coagulation factor VII (FVII) initiates the extrinsic coagulation pathway. We previously demonstrated that progesterone increases TF, coagulation and invasion in breast cancer cell lines. Herein, we investigated if tissue factor pathway inhibitor (TFPI) could down-regulate progesterone-increased TF activity in these cells. Classically, TFPI redistributes TF-FVII-FX-TFPI in an inactive quaternary complex to membrane associated lipid raft regions. Herein, we demonstrate that TF increased by progesterone is localized to the heavy membrane fraction, despite progesterone-increased coagulation originating almost exclusively from lipid raft domains, where TF levels are extremely low. The progesterone increase in coagulation is not a rapid effect, but is progesterone receptor (PR) dependent and requires protein synthesis. Although a partial relocalization of TF occurs, TFPI does not require the redistribution to lipid rafts to inhibit coagulation or invasion. Inhibition by TFPI and anti-TF antibodies in lipid raft membrane fractions confirmed the dependence on TF for progesterone-mediated coagulation. Through the use of pathway inhibitors, we further demonstrate that the TF up-regulated by progesterone is not coupled to the progesterone increase in TF-mediated coagulation. However, the progesterone up-regulated TF protein may be involved in progesterone-mediated breast cancer cell invasion, which TFPI also inhibits.
Assuntos
Coagulação Sanguínea , Neoplasias da Mama/metabolismo , Membrana Celular/metabolismo , Lipoproteínas/metabolismo , Progesterona/metabolismo , Tromboplastina/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Fator VIIa/metabolismo , Fator X/metabolismo , Feminino , Humanos , Microdomínios da Membrana/metabolismo , Invasividade Neoplásica , Transporte Proteico , Receptores de Progesterona/metabolismo , Proteínas Recombinantes/metabolismo , Fatores de Tempo , Regulação para CimaRESUMO
2-Methoxyestradiol (2ME) is an endogenous metabolite of 17ß-estradiol with antiangiogenic and antitumor properties, although its mechanisms of action remain unclear. Progestins in hormone replacement therapy increase the risk of breast cancer. Progesterone also enhances the procoagulant activity and invasive potential of progesterone receptor (PR)-positive breast cancer cell lines, an effect largely mediated by induction of tissue factor (TF), the cellular activator of the coagulation cascade. Here we show that 2ME abrogates the induction TF expression in progesterone-treated breast cancer cells via a mechanism that does not involve the estrogen receptor. Instead, we demonstrate that by selectively antagonizing ERK1/2 signaling in breast cancer cells, 2ME limits the transactivation potential of ligand-bound PR and inhibits the expression of endogenous progesterone targets, such as TF and signal transducer and activator of transcription 5. We further demonstrate that 2ME can alter the phosphorylation status of PR. Thus, 2ME prevents progesterone-dependent increase in breast cancer cell invasiveness and procoagulant activity by uncoupling PR from the ERK1/2 signal transduction pathway.