RESUMEN
Preeclampsia (PE) involves inadequate placental function. This can occur due to elevated pro-inflammatory tumor necrosis factor-α (TNF-α). In other tissues, TNF-α signals via sphingosine kinase 1 (SphK1). SphK1 hinders syncytial formation. Whether this occurs downstream of TNF-α signaling is unclear. We hypothesized that placental SphK1 levels are higher in PE and elevated TNF-α decreases syncytial function, increases syncytial shedding, and increases cytokine/factor release via SphK1 activity. Term placental biopsies were analyzed for SphK1 using immunofluorescence and qRT-PCR. Term placental explants were treated after 4 days of culture, at the start of syncytial regeneration, with TNF-α and/or SphK1 inhibitors, PF-543. Syncytialization was assessed by measuring fusion and chorionic gonadotropin release. Cell death and shedding were measured by lactate dehydrogenase release and placental alkaline phosphatase-positive shed particles. Forty-two cytokines were measured using multiplex assays. Placental SphK1 was increased in PE. Increased cell death, shedding, interferon-α2, IFN-γ-induced protein 10, fibroblast growth factor 2, and platelet-derived growth factor-AA release induced by TNF-α were reversed upon SphK1 inhibition. TNF-α increased the release of 26 cytokines independently of SphK1. TNF-α decreased IL-10 release and inhibiting SphK1 reversed this effect. Inhibiting SphK1 alone decreased TNF-α release. Hence, SphK1 partially mediates the TNF-α-induced PE placental phenotype, primarily through cell damage, shedding, and specific cytokine release.
Asunto(s)
Preeclampsia , Factor de Necrosis Tumoral alfa , Vellosidades Coriónicas/metabolismo , Citocinas/metabolismo , Femenino , Humanos , Fenotipo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Placenta/metabolismo , Embarazo , Esfingosina/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Human cytomegalovirus (HCMV) infects 40-70% of adults in developed countries. HCMV proteins and DNA are detected in tumors and metastases, suggesting an association with increased invasion. We investigated HCMV infection in human breast cancer cell lines compared to fibroblasts, a component of tumors, and the role of platelet-derived growth factor receptor-α (PDGFRα). HCMV productively infected HEL299 fibroblasts and, to a lesser extent, Hs578T breast cancer cells. Infection of another triple-negative cell line, MDA-MB-231, and also MCF-7 cells, was extremely low. These disparate infection rates correlated with expression of PDGFRA, which facilitates HCMV uptake. Increasing PDGFRA expression in T-47D breast cancer and BCPAP thyroid cancer cells markedly increased HCMV infection. Conversely, HCMV infection decreased PDGFRA expression, potentially attenuating signaling through this receptor. HCMV infection of fibroblasts promoted the secretion of proinflammatory factors, whereas an overall decreased secretion of inflammatory factors was observed in infected Hs578T cells. We conclude that HCMV infection in tumors will preferentially target tumor-associated fibroblasts and breast cancer cells expressing PDGFRα. HCMV infection in the tumor microenvironment, rather than cancer cells, will increase the inflammatory milieu that could enhance metastasis involving lysophosphatidate.
Asunto(s)
Neoplasias de la Mama/genética , Infecciones por Citomegalovirus/genética , Lisofosfolípidos/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/patología , Neoplasias de la Mama/virología , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/patología , Infecciones por Citomegalovirus/virología , Femenino , Fibroblastos/patología , Fibroblastos/virología , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Lisofosfolípidos/metabolismo , Células MCF-7 , Metástasis de la Neoplasia/genética , Transducción de Señal/genética , Microambiente Tumoral/genética , Internalización del VirusRESUMEN
We have previously established that adipose tissue adjacent to breast tumors becomes inflamed by tumor-derived cytokines. This stimulates autotaxin (ATX) secretion from adipocytes, whereas breast cancer cells produce insignificant ATX. Lysophosphatidate produced by ATX promotes inflammatory cytokine secretion in a vicious inflammatory cycle, which increases tumor growth and metastasis and decreases response to chemotherapy. We hypothesized that damage to adipose tissue during radiotherapy for breast cancer should promote lysophosphatidic acid (LPA) signaling and further inflammatory signaling, which could potentially protect cancer cells from subsequent fractions of radiation therapy. To test this hypothesis, we exposed rat and human adipose tissue to radiation doses (0.25-5 Gy) that were expected during radiotherapy. This exposure increased mRNA levels for ATX, cyclooxygenase-2, IL-1ß, IL-6, IL-10, TNF-α, and LPA1 and LPA2 receptors by 1.8- to 5.1-fold after 4 to 48 h. There were also 1.5- to 2.5-fold increases in the secretion of ATX and 14 inflammatory mediators after irradiating at 1 Gy. Inhibition of the radiation-induced activation of NF-κB, cyclooxygenase-2, poly (ADP-ribose) polymerase-1, or ataxia telangiectasia and Rad3-related protein blocked inflammatory responses to γ-radiation. Consequently, collateral damage to adipose tissue during radiotherapy could establish a comprehensive wound-healing response that involves increased signaling by LPA, cyclooxygenase-2, and other inflammatory mediators that could decrease the efficacy of further radiotherapy or chemotherapy.-Meng, G., Tang, X., Yang, Z., Benesch, M. G. K., Marshall, A., Murray, D., Hemmings, D. G., Wuest, F., McMullen, T. P. W., Brindley, D. N. Implications for breast cancer treatment from increased autotaxin production in adipose tissue after radiotherapy.
Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/radioterapia , Regulación Enzimológica de la Expresión Génica/efectos de la radiación , Hidrolasas Diéster Fosfóricas/metabolismo , Tejido Adiposo/metabolismo , Tejido Adiposo/efectos de la radiación , Animales , Línea Celular Tumoral , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Femenino , Humanos , Hidrolasas Diéster Fosfóricas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores del Ácido Lisofosfatídico/genética , Receptores del Ácido Lisofosfatídico/metabolismoRESUMEN
The placenta is the physiological bridge between mother and fetus and has life-sustaining functions during pregnancy, including metabolic regulation, fetal protection and hormone secretion. Nucleobindin-2 (NUCB2) is a calcium- and DNA-binding protein and precursor of nesfatin-1, a signalling peptide with multiple functions, including regulation of energy homeostasis and glucose transport. These are also key functions of the placenta, yet NUCB2/nesfatin-1 expression has never been comprehensively studied in this organ. In the present study, mouse placental samples from Embryonic Day (E) 7.5 to E17.5 and human chorionic villi from the first and second trimester, as well as term pregnancy, were analysed for NUCB2/nesfatin-1 expression by immunohistochemistry with an antiserum that recognised both NUCB2 and nesfatin-1. From E7.5 to E9.5, NUCB2/nesfatin-1 was expressed in the ectoplacental cone, then parietal trophoblast giant cells and early spongiotrophoblast. At E10.5-12.5, NUCB2/nesfatin-1 expression became detectable in the developing labyrinth. From E12.5 and onwards, NUCB2/nesfatin-1 was expressed in the glycogen trophoblast cells, as well as highly expressed in syncytiotrophoblast, sinusoidal trophoblast giant cells and fetal capillary endothelial cells of the labyrinth. In all trimesters of human pregnancy, NUCB2/nesfatin-1 was highly expressed in syncytiotrophoblast. In addition, there was a significant increase in NUCB2 expression in human primary trophoblast cells induced to syncytialise. Thus, the haemochorial mammalian placenta is a novel source of NUCB2/nesfatin-1 and likely a site of its action, with potential roles in glucose homeostasis and/or nutrient sensing.
Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Placenta/metabolismo , Trofoblastos/metabolismo , Animales , Diferenciación Celular , Células Cultivadas , Femenino , Edad Gestacional , Ratones Endogámicos C57BL , Nucleobindinas , Placenta/citología , Embarazo , Trimestres del Embarazo , Cultivo Primario de Células , Transducción de Señal , Factores de TiempoRESUMEN
Compared to normal tissues, many cancer cells overexpress autotaxin (ATX). This secreted enzyme produces extracellular lysophosphatidate, which signals through 6 GPCRs to drive cancer progression. Our previous work showed that ATX inhibition decreases 4T1 breast tumor growth in BALB/c mice by 60% for about 11 d. However, 4T1 cells do not produce significant ATX. Instead, the ATX is produced by adjacent mammary adipose tissue. We investigated the molecular basis of this interaction in human and mouse breast tumors. Inflammatory mediators secreted by breast cancer cells increased ATX production in adipose tissue. The increased lysophosphatidate signaling further increased inflammatory mediator production in adipose tissue and tumors. Blocking ATX activity in mice bearing 4T1 tumors with 10 mg/kg/d ONO-8430506 (a competitive ATX inhibitor, IC90 = 100 nM; Ono Pharma Co., Ltd., Osaka, Japan) broke this vicious inflammatory cycle by decreasing 20 inflammatory mediators by 1.5-8-fold in cancer-inflamed adipose tissue. There was no significant decrease in inflammatory mediator levels in fat pads that did not bear tumors. ONO-8430506 also decreased plasma TNF-α and G-CSF cytokine levels by >70% and leukocyte infiltration in breast tumors and adjacent adipose tissue by >50%. Hence, blocking tumor-driven inflammation by ATX inhibition is effective in decreasing tumor growth in breast cancers where the cancer cells express negligible ATX.
Asunto(s)
Tejido Adiposo/enzimología , Neoplasias de la Mama/enzimología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glándulas Mamarias Animales/enzimología , Glándulas Mamarias Humanas/enzimología , Neoplasias Mamarias Experimentales/enzimología , Proteínas de Neoplasias/biosíntesis , Hidrolasas Diéster Fosfóricas/biosíntesis , Tejido Adiposo/patología , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Humanos , Glándulas Mamarias Animales/patología , Glándulas Mamarias Humanas/patología , Neoplasias Mamarias Experimentales/genética , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Proteínas de Neoplasias/genética , Hidrolasas Diéster Fosfóricas/genéticaRESUMEN
Maternal carbohydrate intake is one important determinant of fetal body composition, but whether increased exposure to individual sugars has long-term adverse effects on the offspring is not well established. Therefore, we examined the effect of fructose feeding on the mother, placenta, fetus and her offspring up to 6 months of life when they had been weaned onto a standard rodent diet and not exposed to additional fructose. Dams fed fructose were fatter, had raised plasma insulin and triglycerides from mid-gestation and higher glucose near term. Maternal resistance arteries showed changes in function that could negatively affect regulation of blood pressure and tissue perfusion in the mother and development of the fetus. Fructose feeding had no effect on placental weight or fetal metabolic profiles, but placental gene expression for the glucose transporter GLUT1 was reduced, whereas the abundance of sodium-dependent neutral amino acid transporter-2 was raised. Offspring born to fructose-fed and control dams were similar at birth and had similar post-weaning growth rates, and neither fat mass nor metabolic profiles were affected. In conclusion, raised fructose consumption during reproduction results in pronounced maternal metabolic and vascular effects, but no major detrimental metabolic effects were observed in offspring up to 6 months of age.
Asunto(s)
Dieta , Fructosa/administración & dosificación , Efectos Tardíos de la Exposición Prenatal , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Peso Corporal , Femenino , Enfermedades Metabólicas , Placenta , Embarazo , Ratas WistarRESUMEN
A crucial factor for effective villous trophoblast fusion in the human placenta is the transient deregulation of plasma membrane phospholipid asymmetry leading to externalization of phosphatidylserine to the outer membrane leaflet. Screening of scramblase family members implicated in the collapse of phospholipid asymmetry revealed that phospholipid scramblase 1 (PLSCR1) is strongly expressed in villous trophoblast. Therefore, we assessed the putative role of PLSCR1 in villous trophoblast fusion. Spatio-temporal analysis in first trimester and term placenta showed abundant expression of PLSCR1 in syncytiotrophoblast, macrophages and endothelial cells, while it was virtually absent in villous cytotrophoblasts. For functional studies, BeWo cells, isolated primary term trophoblasts and first trimester villous explants were used. During forskolin-mediated BeWo cell differentiation, neither PLSCR1 mRNA nor protein levels showed significant changes. In contrast, when primary trophoblasts were stimulated with Br-cAMP, a decrease in PLSCR1 mRNA and protein expression was observed. To elucidate a role for PLSCR1 in syncytialization, we used RNA interference and a chemical scramblase inhibitor, R5421 (ethanedioic acid). Silencing of PLSCR1 using siRNA had no effects while inhibition of scramblase activity by R5421 increased GCM-1 mRNA expression, beta-hCG protein secretion and fusion rates of BeWo cells. In primary trophoblasts and villous explants, no effects of siRNA or R5421 treatment on fusion were detected. This study provides data on PLSCR1 localization and general expression in the human placenta. The data make it tempting to speculate on a role of PLSCR1 in negatively regulating trophoblast fusion.
Asunto(s)
Fusión Celular , Proteínas de Transferencia de Fosfolípidos/metabolismo , Trofoblastos/enzimología , Diferenciación Celular , Línea Celular , Gonadotropina Coriónica/metabolismo , Proteínas de Unión al ADN , Inhibidores Enzimáticos/farmacología , Femenino , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Transferencia de Fosfolípidos/antagonistas & inhibidores , Proteínas de Transferencia de Fosfolípidos/genética , Embarazo , Primer Trimestre del Embarazo , Interferencia de ARN , Transducción de Señal , Factores de Tiempo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transfección , Trofoblastos/efectos de los fármacosRESUMEN
Metastasis remains a major challenge in treating breast cancer. Breast tumors metastasize to organ-specific locations such as the brain, lungs, and bone, but why some organs are favored over others remains unclear. Breast tumors also show heterogeneity, plasticity, and distinct microenvironments. This contributes to treatment failure and relapse. The interaction of breast cancer cells with their metastatic microenvironment has led to the concept that primary breast cancer cells act as seeds, whereas the metastatic tissue microenvironment (TME) is the soil. Improving our understanding of this interaction could lead to better treatment strategies for metastatic breast cancer. Targeted treatments for different subtypes of breast cancers have improved overall patient survival, even with metastasis. However, these targeted treatments are based upon the biology of the primary tumor and often these patients' relapse, after therapy, with metastatic tumors. The advent of immunotherapy allowed the immune system to target metastatic tumors. Unfortunately, immunotherapy has not been as effective in metastatic breast cancer relative to other cancers with metastases, such as melanoma. This review will describe the heterogeneic nature of breast cancer cells and their microenvironments. The distinct properties of metastatic breast cancer cells and their microenvironments that allow interactions, especially in bone and brain metastasis, will also be described. Finally, we will review immunotherapy approaches to treat metastatic breast tumors and discuss future therapeutic approaches to improve treatments for metastatic breast cancer.
RESUMEN
BACKGROUND: The Maternal-Infant Research on Environmental Chemicals (MIREC) Study was established to obtain Canadian biomonitoring data for pregnant women and their infants, and to examine potential adverse health effects of prenatal exposure to priority environmental chemicals on pregnancy and infant health. METHODS: Women were recruited during the first trimester from 10 sites across Canada and were followed through delivery. Questionnaires were administered during pregnancy and post-delivery to collect information on demographics, occupation, life style, medical history, environmental exposures and diet. Information on the pregnancy and the infant was abstracted from medical charts. Maternal blood, urine, hair and breast milk, as well as cord blood and infant meconium, were collected and analysed for an extensive list of environmental biomarkers and nutrients. Additional biospecimens were stored in the study's Biobank. The MIREC Research Platform encompasses the main cohort study, the Biobank and follow-up studies. RESULTS: Of the 8716 women approached at early prenatal clinics, 5108 were eligible and 2001 agreed to participate (39%). MIREC participants tended to smoke less (5.9% vs. 10.5%), be older (mean 32.2 vs. 29.4 years) and have a higher education (62.3% vs. 35.1% with a university degree) than women giving birth in Canada. CONCLUSIONS: The MIREC Study, while smaller in number of participants than several of the international cohort studies, has one of the most comprehensive datasets on prenatal exposure to multiple environmental chemicals. The biomonitoring data and biological specimen bank will make this research platform a significant resource for examining potential adverse health effects of prenatal exposure to environmental chemicals.
Asunto(s)
Contaminantes Ambientales/efectos adversos , Bienestar del Lactante , Exposición Materna/efectos adversos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Adolescente , Adulto , Biomarcadores , Canadá , Estudios de Cohortes , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Femenino , Humanos , Lactante , Masculino , Embarazo , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Cytomegalovirus (CMV) infections are associated with vascular diseases in the human population. We have previously shown vascular dysfunction in systemic and uterine arteries dissected from nonpregnant (NP) mouse CMV (mCMV)-infected mice that was further impaired during late pregnancy (LP). CMV attachment alone through glycoprotein B (GB) can generate signals that impact vascular tone regulation. However, the contribution of direct virus interactions with endothelium to the vascular dysfunction we previously observed after in vivo mCMV infection is not known. We used a pressure myograph system to infuse GB or whole intact mCMV inside arteries dissected from uninfected mice and assessed vasodilation to methacholine infused inside pressurized arteries rather than applied abluminally. These results were compared to those observed after methacholine infusion into untreated arteries dissected from mCMV-infected mice. In mesenteric arteries, vasodilation to infused methacholine did not differ among treatments in NP or LP groups in contrast to previously published studies. However, increased vasoconstrictor activity was unmasked after blocking thromboxane receptors or prostaglandin production. Vasodilation in uterine arteries from uninfected NP mice to infused methacholine was increased by both GB and whole intact mCMV pretreatment. Untreated uterine arteries from mCMV-infected NP mice showed even greater vasodilation. There was no effect of GB or whole intact mCMV pretreatment in uterine arteries from uninfected LP mice, whereas vasodilation to infused methacholine was reduced in untreated uterine arteries from mCMV-infected LP mice. CMV exerts direct effects on vascular function which should be considered during viral reactivation leading to viremia and during GB-based vaccine administration.
Asunto(s)
Citomegalovirus/fisiología , Células Endoteliales , Arterias Mesentéricas/fisiología , Complicaciones Infecciosas del Embarazo/fisiopatología , Vasodilatación , Proteínas del Envoltorio Viral/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/fisiopatología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/inmunología , Células Endoteliales/fisiología , Femenino , Edad Gestacional , Masculino , Arterias Mesentéricas/efectos de los fármacos , Arterias Mesentéricas/inmunología , Arterias Mesentéricas/virología , Cloruro de Metacolina/farmacología , Ratones , Ratones Endogámicos C57BL , Embarazo/efectos de los fármacos , Embarazo/fisiología , Complicaciones Infecciosas del Embarazo/patología , Flujo Sanguíneo Regional/efectos de los fármacos , Flujo Sanguíneo Regional/fisiología , Arteria Uterina/efectos de los fármacos , Arteria Uterina/fisiología , Útero/irrigación sanguínea , Útero/efectos de los fármacos , Útero/virología , Vasoconstrictores/farmacología , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiologíaRESUMEN
Human cytomegalovirus (HCMV) infects 40-70% of adults in developed countries. Detection of HCMV DNA and/or proteins in breast tumors varies considerably, ranging from 0-100%. In this study, nested PCR to detect HCMV glycoprotein B (gB) DNA in breast tumors was shown to be sensitive and specific in contrast to the detection of DNA for immediate early genes. HCMV gB DNA was detected in 18.4% of 136 breast tumors while 62.8% of 94 breast cancer patients were seropositive for HCMV. mRNA for the HCMV immediate early gene was not detected in any sample, suggesting viral latency in breast tumors. HCMV seropositivity was positively correlated with age, body mass index and menopause. Patients who were HCMV seropositive or had HCMV DNA in their tumors were 5.61 (CI 1.77-15.67, p = 0.003) or 5.27 (CI 1.09-28.75, p = 0.039) times more likely to develop Stage IV metastatic tumors, respectively. Patients with HCMV DNA in tumors experienced reduced relapse-free survival (p = 0.042). Being both seropositive with HCMV DNA-positive tumors was associated with vascular involvement and metastasis. We conclude that determining the seropositivity for HCMV and detection of HCMV gB DNA in the breast tumors could identify breast cancer patients more likely to develop metastatic cancer and warrant special treatment.
RESUMEN
Human cytomegalovirus (HCMV) is the leading cause of congenital disease in the developed world. Transmission of HCMV to the fetus can occur through the villous placenta. Previously, we have shown that although syncytiotrophoblast (ST) can be productively infected, it is more likely that HCMV reaches the fetus through breaks in the ST than through basal release of progeny virus from infected ST. Progeny virus released on the maternal side could interact back with the ST and accumulate. In pregnancy, the organ distribution of disease burden is dramatically shifted, with the placenta reported as a reservoir for some pathogens. Thus, we propose that the ST layer functions as a viral reservoir, where HCMV is harbored and ultimately protected from degradation. Using primary cytotrophoblasts differentiated into an ST culture in vitro and challenged with HCMV, we have defined reversible binding between the virus and trophoblasts that protects the virus from degradation. This is blocked by treatment with low pH and neutralizing intravenous immunoglobulin. This reversible binding likely is to heparan sulfate proteoglycans, because heparin treatment blocks it. Importantly, we show that bound and released virus maintained in culture for at least 48 h results from inoculum and not progeny virus. Thus, the placenta has the potential to accumulate a relatively high steady-state level of virus within the intervillous space resulting from localized binding and release at the ST. A better understanding of the molecular interactions between HCMV and ST will provide insights regarding interventions to prevent or minimize congenital transmission.
Asunto(s)
Citomegalovirus/metabolismo , Proteoglicanos de Heparán Sulfato/metabolismo , Interacciones Huésped-Patógeno , Trofoblastos/virología , Acoplamiento Viral , Anticuerpos Neutralizantes , Células CACO-2 , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/transmisión , Femenino , Heparina , Humanos , Concentración de Iones de Hidrógeno , Inmunoglobulinas Intravenosas , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Trofoblastos/metabolismo , Inactivación de VirusRESUMEN
Signaling by the bioactive sphingolipid, sphingosine 1-phosphate (S1P), and its precursors are emerging areas in pregnancy research. S1P and ceramide levels increase towards end of gestation, suggesting a physiological role in parturition. However, high levels of circulating S1P and ceramide are correlated with pregnancy disorders such as preeclampsia, gestational diabetes mellitus and intrauterine growth restriction. Expression of placental and decidual enzymes that metabolize S1P and S1P receptors are also dysregulated during pregnancy complications. In this review, we provide an in-depth examination of the signaling mechanism of S1P and ceramide in various reproductive tissues during gestation. These factors determine implantation and early pregnancy success by modulating corpus luteum function from progesterone production to luteolysis through to apoptosis. We also highlight the role of S1P through receptor signaling in inducing decidualization and angiogenesis in the decidua, as well as regulating extravillous trophoblast migration to anchor the placenta into the uterine wall. Recent advances on the role of the S1P:ceramide rheostat in controlling the fate of villous trophoblasts and the role of S1P as a negative regulator of trophoblast syncytialization to a multinucleated placental barrier are discussed. This review also explores the role of S1P in anti-inflammatory and pro-inflammatory signaling, its role as a vasoconstrictor, and the effects of S1P metabolizing enzymes and receptors in pregnancy.
Asunto(s)
Placenta , Esfingolípidos , Ceramidas , Femenino , Humanos , Lisofosfolípidos/metabolismo , Placenta/metabolismo , Embarazo , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato , Trofoblastos/metabolismoRESUMEN
Lysophosphatidate (LPA) and sphingosine 1-phosphate (S1P) promote vasculogenesis, angiogenesis, and wound healing by activating a plethora of overlapping signaling pathways that stimulate mitogenesis, cell survival, and migration. As such, maladaptive signaling by LPA and S1P have major effects in increasing tumor progression and producing poor patient outcomes after chemotherapy and radiotherapy. Many signaling actions of S1P and LPA are not redundant; each are vital in normal physiology and their metabolisms differ. In the present work, we studied how LPA signaling impacts S1P metabolism and signaling in MDA-MB-231 and MCF-7 breast cancer cells. LPA increased sphingosine kinase-1 (SphK1) synthesis and rapidly activated cytosolic SphK1 through association with membranes. Blocking phospholipase D activity attenuated the LPA-induced activation of SphK1 and the synthesis of ABCC1 and ABCG2 transporters that secrete S1P from cells. This effect was magnified in doxorubicin-resistant MCF-7 cells. LPA also facilitated S1P signaling by increasing mRNA expression for S1P1 receptors. Doxorubicin-resistant MCF-7 cells had increased S1P2 and S1P3 receptor expression and show increased LPA-induced SphK1 activation, increased expression of ABCC1, ABCG2 and greater S1P secretion. Thus, LPA itself and LPA-induced S1P signaling counteract doxorubicin-induced death of MCF-7 cells. We conclude from the present and previous studies that LPA promotes S1P metabolism and signaling to coordinately increase tumor growth and metastasis and decrease the effectiveness of chemotherapy and radiotherapy for breast cancer treatment.
Asunto(s)
Lisofosfolípidos , Esfingosina/análogos & derivadosRESUMEN
The regulations of endothelial permeability and vascular tone by sphingosine 1-phosphate (S1P) have been well-studied independently. Little is known about whether the effects of S1P on endothelial permeability can directly influence vascular tone in resistance arteries, which impact blood flow. The endothelium forms a partial barrier that regulates access of circulating agonists to underlying vascular smooth muscle cells (VSMCs). We hypothesized that physiological concentrations of circulating S1P simultaneously control endothelial barrier function and vascular tone through endothelial production of nitric oxide (NO). We adapted the pressure myograph system to simultaneously measure both functions in pressurized mesenteric compared to uterine resistance arteries from wild-type and eNOS KO mice. We established that: 1) S1P interacting directly with the endothelium inside pressurized arteries generates NO that limits endothelial permeability; 2) an intact endothelium forms a partial physical barrier that regulates access of intraluminal S1P to the underlying VSMCs and 3) S1P infused lumenally also generates NO through eNOS that counterbalances the constriction induced by S1P that is able to access VSMCs and this is critical to control vascular tone. We conclude that targeting the S1P signaling system, particularly the capacity to produce NO could be clinically important in the treatment of vascular diseases.
Asunto(s)
Lisofosfolípidos , Óxido Nítrico , Animales , Arterias , Endotelio , Ratones , Esfingosina/análogos & derivados , Esfingosina/farmacologíaRESUMEN
Chronic cytomegalovirus (CMV) infections are implicated in vascular diseases. Recently, we showed that an active mouse CMV (mCMV) infection in nonpregnant mice increased endothelial-dependent vasodilation in isolated mesenteric and uterine arteries. In late pregnancy, while increased vasodilation was found in mesenteric arteries from infected mice, there was a dramatic decrease in uterine arteries. Understanding the mechanisms for these vascular changes during CMV infections is important for pregnancy outcomes and long-term consequences of this chronic infection. Increased nitric oxide (NO) is implicated in CMV-associated atherosclerosis, and CMV replication is dependent on prostaglandin H synthase (PGHS) activity. Alternatively, CMV infections decrease NO under inflammatory conditions. We therefore hypothesized that changes in the contribution by NO or PGHS-induced vasodilators would explain the increased or decreased endothelial-dependent vasodilation in arteries from nonpregnant and late pregnant mice, respectively. We found that the contribution by NO to methacholine-induced vasodilation was significantly increased in mesenteric, but not uterine, arteries isolated from nonpregnant and pregnant mCMV-infected mice. Prostaglandin inhibition did not affect endothelial-dependent vasodilation in any group. Vasodilation responses to sodium nitroprusside, an NO donor, were increased in mesenteric and uterine arteries isolated only from mCMV-infected nonpregnant mice. These results explain the increased vasodilation responses observed in mesenteric arteries from mCMV-infected mice; however, the decreased vasodilation in uterine arteries from pregnant mice could not be explained by these mechanisms. Thus CMV infection affects the contribution of NO differently in endothelial-dependent vasodilation in pregnant compared with nonpregnant mice and also in the mesenteric compared with the uterine vascular bed.
Asunto(s)
Infecciones por Citomegalovirus/metabolismo , Citomegalovirus , Arterias Mesentéricas/metabolismo , Óxido Nítrico/metabolismo , Preñez/metabolismo , Arteria Uterina/metabolismo , Vasodilatación/fisiología , Animales , Modelos Animales de Enfermedad , Endotelio Vascular/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/metabolismo , Nitroprusiato/farmacología , Embarazo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Prostaglandinas/metabolismo , Vasodilatación/efectos de los fármacosRESUMEN
An appropriate balance between uterine quiescence and activation during pregnancy is essential for a successful outcome. Sphingosine 1-phosphate (S1P), a bioactive lipid, increases cell survival, proliferation, and angiogenesis, all important to maintain the pregnancy. Indeed progesterone increases sphingosine kinase 1 (SPHK1) mRNA, which produces S1P. In contrast, induction of prostaglandin endoperoxide synthase 2 by S1P and stimulation of SPHK1 by estradiol and cytokines suggests a role for S1P in the termination of pregnancy. Human decidua is important for regulating the maintenance and termination of pregnancy with production of progesterone receptors, cytokines, and prostaglandins. We hypothesized that S1P is produced by and acts on the decidua to stimulate production of mediators that induce labor. Our objective was to investigate the metabolism of S1P and its receptors in human decidua during pregnancy. We found that SPHK1 protein and activity positively correlated with increasing gestational age in human decidua parietalis. This was accompanied at term by increased expression of the S1P lyase, which irreversibly degrades S1P. This implies increased S1P turnover in the decidua at term. Although the mRNA level of phosphatidic acid phosphatase type 2A and 2B (PPAP2A,B), which dephosphorylate extracellular S1P, were increased at term, PPAP2 activity did not change. Sphingosine 1-phosphate receptor 3 protein expression also increased at term, indicating increased signaling by S1P in the decidua. There were no differences in any parameter tested in decidua from women in labor compared to those who were not. This work provides the first evidence of increased S1P synthesis, degradation, and signaling in human decidua during gestation.
Asunto(s)
Decidua/metabolismo , Enzimas/genética , Regulación del Desarrollo de la Expresión Génica , Lisofosfolípidos/metabolismo , Tercer Trimestre del Embarazo , Esfingosina/análogos & derivados , Adulto , Decidua/enzimología , Activación Enzimática , Enzimas/metabolismo , Femenino , Humanos , Fosfatidato Fosfatasa/genética , Fosfatidato Fosfatasa/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Embarazo , Tercer Trimestre del Embarazo/genética , Tercer Trimestre del Embarazo/metabolismo , Tercer Trimestre del Embarazo/fisiología , Transducción de Señal/genética , Transducción de Señal/fisiología , Esfingosina/metabolismo , Regulación hacia Arriba , Adulto JovenRESUMEN
Extracellular lysophosphatidate (LPA) signalling is regulated by the balance of LPA formation by autotaxin (ATX) versus LPA degradation by lipid phosphate phosphatases (LPP) and by the relative expressions of six G-protein-coupled LPA receptors. These receptors increase cell proliferation, migration, survival and angiogenesis. Acute inflammation produced by tissue damage stimulates ATX production and LPA signalling as a component of wound healing. If inflammation does not resolve, LPA signalling becomes maladaptive in conditions including arthritis, neurologic pain, obesity and cancers. Furthermore, LPA signalling through LPA1 receptors promotes fibrosis in skin, liver, kidneys and lungs. LPA also promotes the spread of tumours to other organs (metastasis) and the pro-survival properties of LPA explain why LPA counteracts the effects of chemotherapeutic agents and radiotherapy. ATX is secreted in response to radiation-induced DNA damage during cancer treatments and this together with increased LPA1 receptor expression leads to radiation-induced fibrosis. The anti-inflammatory agent, dexamethasone, decreases levels of inflammatory cytokines/chemokines. This is linked to a coordinated decrease in the production of ATX and LPA1/2 receptors and increased LPA degradation through LPP1. These effects explain why dexamethasone attenuates radiation-induced fibrosis. Increased LPA signalling is also associated with cardiovascular disease including atherosclerosis and deranged LPA signalling is associated with pregnancy complications including preeclampsia and intrahepatic cholestasis of pregnancy. LPA contributes to chronic inflammation because it stimulates the secretion of inflammatory cytokines/chemokines, which increase further ATX production and LPA signalling. Attenuating maladaptive LPA signalling provides a novel means of treating inflammatory diseases that underlie so many important medical conditions.
Asunto(s)
Enfermedades Cardiovasculares/metabolismo , Fibrosis Pulmonar Idiopática/metabolismo , Lisofosfolípidos/metabolismo , Neoplasias/metabolismo , Complicaciones del Embarazo/metabolismo , Transducción de Señal , Cicatrización de Heridas/fisiología , Animales , Femenino , Humanos , Inflamación/metabolismo , Fosfatidato Fosfatasa/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Embarazo , Receptores Acoplados a Proteínas G/metabolismoRESUMEN
Cytomegalovirus (CMV) infects 40â»70% of women, but infection has been reported in >95% of breast cancer patients. We investigated the consequences of these observations by infecting mice with mCMV or a negative control medium for 4 days, 11 days or 10 weeks to establish active, intermediate or latent infections, respectively. Syngeneic 4T1 or E0771 breast cancer cells were then injected into a mammary fat pad of BALB/c or C57BL/6 mice, respectively. Infection did not affect tumor growth in these conditions, but latently infected BALB/c mice developed more lung metastases. The latent mCMV infection of MMTV-PyVT mice, which develop spontaneous breast tumors, also did not affect the number or sizes of breast tumors. However, there were more tumors that were multilobed with greater blood content, which had enhanced vasculature and decreased collagen content. Most significantly, mCMV infection also increased the number and size of lung metastases, which showed a higher cell proliferation. Viral DNA was detected in breast tumors and lung nodules although viral mRNA was not. These novel results have important clinical implications since an increased metastasis is prognostic of decreased survival. This work provides evidence that treating or preventing HCMV infections may increase the life expectancy of breast cancer patients by decreasing metastasis.
RESUMEN
OBJECTIVE: Neonatal morbidity and mortality can be influenced by maternal health status. Information on maternal and fetal biomarkers of adverse health outcomes is limited. This work aims at identifying maternal biomarkers associated with low and high birth weight for gestational age groups. DESIGN AND SETTINGS: Population-based prospective cohort study of the potential adverse health effects of exposure to environmental contaminants on pregnancy and infant health. METHODS: Third trimester maternal plasma samples (n = 1588) from a pregnancy cohort (Maternal-Infant Research on Environmental Chemicals Study, MIREC) were analyzed for changes in a target spectrum of biomarkers of vascular health (e.g., matrix metalloproteinases MMPs, vascular endothelial cell growth factor VEGF), inflammation (e.g. cellular adhesion molecules CAMs, cytokines, chemokines) by affinity-based multiplex protein array analyses. Multivariate logistic regression analyses were done to examine associations between target plasma biomarkers, maternal-infant characteristics, and birth weight outcomes assessed as small for gestational age (SGA) ≤10th percentile and large for gestational age (LGA) ≥90th percentile groups. RESULTS AND OUTCOMES: Our results revealed that maternal plasma biomarkers monocyte chemoattractant protein-1 MCP-1 (p<0.05, +ve) and VEGF (p<0.05, -ve) along with parity = 1 (p<0.01, -ve) and gestational hypertension (p<0.05, +ve) were associated with SGA births. Meanwhile, LGA was associated with maternal plasma VEGF (p<0.05, +ve) and MMP-9 (p<0.05, -ve) and gestational hypertension (p<0.01, +ve), pre-pregnancy body mass index (p<0.01, +ve), parity (p<0.05, +ve) and education (p<0.05, -ve). CONCLUSIONS: Third trimester maternal plasma biomarkers in combination with maternal health and socioeconomic characteristics can be useful in predicting SGA and LGA outcomes. Maternal vascular health and inflammatory status may contribute to both SGA and LGA births through distinct molecular mechanisms.