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1.
Hum Reprod ; 34(7): 1291-1301, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31188433

RESUMO

STUDY QUESTION: Can of Clinical Genetics, Maastricht University Medical Centre, Maastricht kisspeptin and its analogues regulate the motility of human decidual stromal cells and what intracellular signaling pathways are involved? SUMMARY ANSWER: Kisspeptin analogue-mediated cell motility in human decidual stromal cells via the focal adhesion kinase (FAK)-steroid receptor coactivator (Src) pathway suggesting that kisspeptin may modulate embryo implantation and decidual programming in human pregnancy. WHAT IS KNOWN ALREADY: The extravillous trophoblast invades the maternal decidua during embryo implantation and placentation. The motile behavior and invasive potential of decidual stromal cells regulate embryo implantation and programming of human pregnancy. STUDY DESIGN, SIZE, DURATION: Human decidual stromal cells were isolated from healthy women undergoing elective termination of a normal pregnancy at 6- to 12-week gestation, after informed consent. PARTICIPANTS/MATERIALS, SETTING, METHODS: Kisspeptin analogues were synthetic peptides. Cell motility was estimated by an invasion and migration assay. Immunoblot analysis was performed to investigate the expression of kisspeptin receptor and the effects of kisspeptin analogues on the phosphorylation of FAK and Src. Small interfering RNAs (siRNAs) were used to knock down the expression of kisspeptin receptor, FAK, Src, matrix metallo-proteinases (MMPs) 2 and 9, and extracellular signal-regulated protein kinase (ERK) 1/2. MAIN RESULTS AND THE ROLE OF CHANCE: The kisspeptin receptor was expressed in human decidual stromal cells. Kisspeptin agonist decreased, but antagonist increased, cell motility. Kisspeptin agonist decreased the phosphorylation of FAK and Src tyrosine kinases, whereas antagonist increased it. These effects on phosphorylation were abolished by kisspeptin receptor siRNA. The activation of cell motility by kisspeptin analogues was suppressed by siRNA knockdown of endogenous FAK (decreased 66%), Src (decreased 60%), kisspeptin receptor (decreased 26%), MMP-2 (decreased 36%), MMP-9 (decreased 23%), and ERK 1/2 inhibitor (decreased 27%). LIMITATIONS, REASONS FOR CAUTION: Human decidual stromal cells were obtained from women having terminations after 6-12 weeks of pregnancy and differences in timing could affect their properties. WIDER IMPLICATIONS OF THE FINDINGS: Kisspeptin acting within the endometrium has a potential modulatory role on embryo implantation and decidual programming of human pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grant NSC-104-2314-B-182A-146-MY2 (to H.-M.W.) from the Ministry of Science and Technology, Taiwan, and grants CMRPG3E0401 and CMRPG3E0402 (to H.-M.W.). This work was also supported by grants from the Canadian Institutes of Health Research to P.C.K.L. P.C.K.L. is the recipient of a Child & Family Research Institute Distinguished Investigator Award. The authors have no conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Movimento Celular , Decídua/citologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Kisspeptinas/fisiologia , Quinases da Família src/metabolismo , Adulto , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Cultura Primária de Células , Células Estromais/fisiologia
2.
BJOG ; 117(1): 99-108, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20002372

RESUMO

OBJECTIVE: Pre-eclampsia involves a maternal inflammatory response that differs from both normal pregnancy and normotensive intrauterine growth restriction (IUGR). Our objective was to examine neutrophil Toll-like receptor (TLR), cryopyrin, nuclear factor-kappaB (NF-kappaB) subunit and interleukin-1beta (IL-1beta), and inflammatory cytokine profiles in women with pre-eclampsia or normotensive IUGR, as well as in normal pregnancy and non-pregnancy controls. DESIGN AND METHOD: A case-control study was performed. We examined the messenger RNA (mRNA) and protein expressions of TLR4 and TLR2, mRNA levels of cryopyrin, IL-1beta, NF-kappaB subunits p50 and p65, as well as maternal serum inflammatory cytokine profiles (IL-2, IL-6, tumour necrosis factor-alpha [TNF-alpha], interferon-gamma [IFN-gamma] and IL-10) in women with and without pre-eclampsia using real-time reverse transcription polymerase chain reactions, flow cytometry and multiplex immunoassays. SETTING: A single tertiary maternity hospital in Vancouver, Canada. POPULATION: Women with early-onset pre-eclampsia (<34 weeks of gestation, n = 25), women with late-onset pre-eclampsia (>or=34(+0) weeks of gestation, n = 25), women with normotensive IUGR (n = 25), women with normal pregnancy (n = 75) and non-pregnancy (n = 25) controls. RESULTS: Women with pre-eclampsia (as a single combined group of early- and late-onset, and particularly in women with early-onset pre-eclampsia) had increased TLR2 and TLR4 mRNA and protein expressions elevated cryopyrin, NF-kappaB subunit, and IL-1beta mRNA expression, and TNF-alpha:IL-10 and IL-6:IL-10 ratios compared with other groups. CONCLUSIONS: These data suggest that TLRs and cryopyrin may modulate the innate immune response of the maternal syndrome of pre-eclampsia, and might also trigger the differential inflammatory response existing between early onset pre-eclampsia and normotensive IUGR.


Assuntos
Proteínas de Transporte/metabolismo , Pré-Eclâmpsia/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Retardo do Crescimento Fetal/imunologia , Humanos , Imunidade Inata , Interleucinas/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Neutrófilos/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Regulação para Cima
3.
Int J Gynecol Cancer ; 18(6): 1234-47, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18217967

RESUMO

Serous borderline ovarian tumors (SBOTs) are differentiated, slow growing, noninvasive, and have a better prognosis than their invasive counterparts, but recurrence and progression to invasive carcinomas are common, and unlike high-grade serous carcinomas, they tend to be nonresponsive to chemotherapy. However, due to a lack of culture systems and animal models, information about the properties of SBOT and their changes with neoplastic progression is extremely limited. Our objective was to establish a cell culture model for SBOTs and to characterize their phenotype and genotype. We compared cultures derived from two SBOTs, one of which was a short-term culture containing a BRAF mutation but few other cytogenetic changes while the other culture developed into a spontaneously immortalized permanent cell line and had numerical and structural chromosomal abnormalities but lacked RAS/BRAF mutations. Both cultures formed whorl-like epithelial colonies and resembled low-grade invasive carcinomas by their secretion of CA125 and oviduct-specific glycoprotein, production of matrix metalloproteinases, E-cadherin expression, and telomerase activity. Other characteristics associated with neoplastic transformation, including invasiveness, anchorage-independent growth, and tumorigenicity, were not observed. Importantly, cell motility was reduced in both lines, likely contributing to the lack of invasiveness. The results reveal a striking phenotypic similarity between the two cell lines, regardless of their cytogenetic diversity, which suggests that their characteristic phenotype is regulated to a large degree by epigenetic and environmental factors. In conclusion, we have established the first permanent SBOT cell line, which provides a new model to elucidate the undefined relationship of SBOTs to invasive ovarian carcinomas.


Assuntos
Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Adulto , Animais , Sequência de Bases , Biomarcadores , Diferenciação Celular , Movimento Celular , Feminino , Dosagem de Genes/genética , Genótipo , Saúde , Humanos , Camundongos , Mutação/genética , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Fatores de Tempo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Curr Mol Med ; 16(3): 299-311, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26917260

RESUMO

Although GHRH and GHRH-R are recognized as key factors in placental development, little is known about the mechanism(s) of the regulation in trophoblastic cells during placental development. The objective of this study is to determine the potential relationship between the expression levels of GHRH-R and the placental and JEG-3 cell function. Furthermore, we aim to investigate the downstream pathways of GHRH/GHRH-R axis in the control of the JEG-3 cell viability and apoptosis. In this study, we detected the expression pattern of GHRH-R in human chorionic villous tissues and JEG-3 cell. Then, we evaluated the effects of GHRH/GHRH-R and the downstream pathways by using GHRH antagonist (JMR-132) on JEG-3 cell. Our present study found the expressions of GHRH-R in placental villous tissues and JEG-3 cell, and the expression levels of GHRH-R was significantly lower in villous tissues of early pregnancy loss when compared to normal controls. JMR-132 inhibited cellular viability and induced apoptosis in JEG-3 cell in a time and dosedependent manners through activation of caspase-3, p38, and p53, as well as inhibition of phosphorylation of Akt. Interestingly, ER stress markers such as GRP78, ubiquitinated proteins and phospho-eIF2α were significantly increased in JEG-3 cell after being treated with JMR-132. Conversely, pretreated with salubrinal (a selective inhibition of protein phosphatase 1-mediated eIF2α dephosphorylation), JEG-3 cells were rescued from JMR-132-mediated cell growth inhibition, and abolished JMR-132-induced cleaved caspase-3, CHOP, phospho-p53, and ubiquitinated proteins accumulation. Knockdown of endogenous GHRH-R significantly abolished the JMR-132-induced cleaved caspase-3 and activation of p38. In conclusion, our results, for the first time, demonstrated the expression levels of GHRH-R were closely related to the placental function. Inhibition of GHRH-R by using GHRH antagonist in JEG-3 cell may reduce cell viability and induce apoptosis through inactivation of Akt and ER stress via phosphorylation of eIF2α. These observations have enriched our understanding on the function of GHRH/GHRH-R axis and the downstream pathways in the control of the placental development. The Most Important Aspect of the Paper: Our present study for the first time provided evidences that GHRH and GHRH-R loops involve in JEG-3 cell viability and apoptosis through Akt and eIF2α pathways.


Assuntos
Vilosidades Coriônicas/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Hormônio Liberador de Hormônio do Crescimento/genética , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Trofoblastos/metabolismo , Aborto Espontâneo/genética , Aborto Espontâneo/metabolismo , Aborto Espontâneo/patologia , Adulto , Apoptose , Estudos de Casos e Controles , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Vilosidades Coriônicas/efeitos dos fármacos , Vilosidades Coriônicas/patologia , Cinamatos/farmacologia , Chaperona BiP do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Regulação da Expressão Gênica , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Humanos , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Sermorelina/análogos & derivados , Sermorelina/antagonistas & inibidores , Sermorelina/farmacologia , Transdução de Sinais , Tioureia/análogos & derivados , Tioureia/farmacologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Anim Reprod Sci ; 88(1-2): 95-113, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15982835

RESUMO

Gonadotropin releasing hormone (GnRH) is a hypothalamic neuronal secretory decapeptide that plays a pivotal role in mammalian reproduction. GnRH and its analogues are used extensively in the treatment of hormone dependent diseases and assisted reproductive technology. Fourteen structural variants and three different forms of GnRH, named as hypothalamic GnRH or GnRH-I, mid brain GnRH or GnRH-II and GnRH-III across various species of protochordates and vertebrates have been recognised. The hormone acts by binding to cell surface transmembrane G protein coupled receptors (GPCRs) and activates Gq/11 subfamily of G proteins. Although hypothalamus and pituitary are the principal source and target sites for GnRH, several reports have recently suggested extra-hypothalamic GnRH and GnRH receptors in various reproductive tissues such as ovaries, placenta, endometrium, oviducts, testes, prostrate, and mammary glands. GnRH-II appears to be predominantly expressed in extra pituitary reproductive tissues where it produces its effect by PLC, PKA2, PLD, and AC cell signalling pathways. In these tissues, GnRH is considered to act by autocrine or paracrine manner and regulate ovarian steroidogenesis by having stimulatory as well as inhibitory effect on the production of steroid hormones and apoptosis in ovarian follicle and corpus luteum. In male gonads, GnRH has been shown to cause a direct stimulatory effect on basal steroidogenesis and an inhibitory effect on gonadotropin-stimulated androgen biosynthesis. Recent studies have shown that GnRH is more abundantly present in ovarian, endometrial and prostrate carcinomas. The presence of type-II GnRH receptors in reproductive tissues (e.g. gonads, prostrate, endometrium, oviduct, placenta, and mammary glands) suggests existence of distinct role(s) for type-II GnRH molecule in these tissues. The existence of different GnRH forms indicates the presence of distinctive cognate receptors types in vertebrates and is a productive area of research and may contribute to the development of new generation of GnRH analogues with highly selective and controlled action on different reproductive tissues and the target-specific GnRH analogues could be developed.


Assuntos
Hormônio Liberador de Gonadotropina/análise , Hormônio Liberador de Gonadotropina/fisiologia , Reprodução , Animais , Apoptose , Feminino , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Humanos , Hipotálamo/química , Masculino , Especificidade de Órgãos , Ovário/química , Ovário/citologia , Ovário/efeitos dos fármacos , Hipófise/química , Hipófise/fisiologia , Placenta/química , Gravidez , Receptores LHRH/análise , Receptores LHRH/genética , Receptores LHRH/fisiologia , Testículo/química
6.
Cell Death Dis ; 6: e1864, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-26313915

RESUMO

Ovarian high-grade serous carcinomas (HGSCs) and invasive low-grade serous carcinomas (LGSCs) are considered to be distinct entities. In particular, LGSCs are thought to arise from non-invasive serous borderline ovarian tumors (SBOTs) and show poor responsiveness to conventional chemotherapy. The pro-apoptotic effects of CD40 ligand (CD40L) have been demonstrated in HGSC, though the underlying mechanisms are not fully understood. Conversely, the therapeutic potential of the CD40L-CD40 system has yet to be evaluated in LGSC. We now show that CD40 protein is focally expressed on tumor cells in two of five primary LGSCs compared with no expression in eight primary SBOTs. Treatment with CD40L or agonistic CD40 antibody decreased the viability of LGSC-derived MPSC1 and VOA1312 cells, but not SBOT3.1 cells. Small interfering RNA (siRNA) targeting CD40 was used to show that it is required for these reductions in cell viability. CD40L treatment increased cleaved caspase-3 levels in MPSC1 cells though, surprisingly, neither pan-caspase inhibitor nor caspase-3 siRNA reversed or even attenuated CD40L-induced cell death. In addition, CD40-induced cell death was not affected by knockdown of the mitochondrial proteins apoptosis-inducing factor (AIF) and endonuclease G (EndoG). Interestingly, CD40L-induced cell death was blocked by necrostatin-1, an inhibitor of receptor-interacting protein 1 (RIP1), and attenuated by inhibitors of RIP3 (GSK'872) or MLKL (mixed lineage kinase domain-like; necrosulfonamide). Our results indicate that the upregulation of CD40 may be relatively common in LGSC and that CD40 activation induces RIP1-dependent, necroptosis-like cell death in LGSC cells.


Assuntos
Antígenos CD40/genética , Ligante de CD40/farmacologia , Cistadenocarcinoma Seroso/genética , Regulação Neoplásica da Expressão Gênica , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/genética , Acrilamidas/farmacologia , Anticorpos/farmacologia , Fator de Indução de Apoptose/antagonistas & inibidores , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Antígenos CD40/agonistas , Antígenos CD40/antagonistas & inibidores , Antígenos CD40/metabolismo , Ligante de CD40/genética , Ligante de CD40/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patologia , Progressão da Doença , Endodesoxirribonucleases/antagonistas & inibidores , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Feminino , Humanos , Imidazóis/farmacologia , Indóis/farmacologia , Gradação de Tumores , Complexo de Proteínas Formadoras de Poros Nucleares/antagonistas & inibidores , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais , Sulfonamidas/farmacologia
7.
Endocr Relat Cancer ; 10(2): 169-77, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12790779

RESUMO

Gonadotrophin-releasing hormone (GnRH) functions as a key neuroendocrine regulator of the hypothalamic-pituitary-gonadal axis. In addition to the hypothalamus and pituitary gland, GnRH and its receptor have been detected in other reproductive tissues including the gonads, placenta and tumours arising from these tissues. Recently, a second form of GnRH (GnRH-II) and type II GnRH receptor have been found in normal ovarian surface epithelium and neoplastic counterparts. The two types of GnRH may play an important role as an autocrine/paracrine regulator of reproductive functions and ovarian tumour growth. In this review, the distribution and potential roles of GnRH-I/-II and their GnRH receptors in the ovarian cells and ovarian cancer will be discussed.


Assuntos
Neoplasias Ovarianas/metabolismo , Ovário/fisiologia , Receptores LHRH/fisiologia , Feminino , Humanos
8.
Oncogene ; 32(8): 1041-9, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22508482

RESUMO

Loss of the cell adhesion protein E-cadherin increases the invasive capability of ovarian cancer cells. We have previously shown that epidermal growth factor (EGF) downregulates E-cadherin and induces ovarian cancer cell invasion through the H(2)O(2)/p38 MAPK-mediated upregulation of the E-cadherin transcriptional repressor Snail. However, the molecular mechanisms underlying the EGF-induced downregulation of E-cadherin are not fully understood. In the current study, we demonstrated that treatment of two ovarian cancer cell lines, SKOV3 and OVCAR5, with EGF induced the expression of the transcription factor Egr-1, and this induction was abolished by small interfering RNA (siRNA)-mediated depletion of the EGF receptor. EGF-induced Egr-1 expression required the activation of the ERK1/2 and PI3K/Akt signaling pathways and was unrelated to EGF-induced H(2)O(2) production and activation of the p38 MAPK pathway. Moreover, depletion of Egr-1 with siRNA abolished the EGF-induced downregulation of E-cadherin and increased cell invasion. Interestingly, siRNA depletion of Egr-1 attenuated the EGF-induced expression of Slug, but not that of Snail. Moreover, chromatin immunoprecipitation (ChIP) analysis showed that Slug is a target gene of Egr-1. These results provide evidence that Egr-1 is a mediator that is involved in the EGF-induced downregulation of E-cadherin and increased cell invasion. Our results also demonstrate that EGF activates two independent signaling pathways, which are the H(2)O(2)/p38 MAPK-mediated upregulation of Snail expression and the Egr-1-mediated upregulation of Slug expression. These two signaling pathways contribute to the EGF-induced downregulation of E-cadherin, which subsequently increases the invasive capability of ovarian cancer cells.


Assuntos
Caderinas/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Neoplasias Ovarianas/metabolismo , Fatores de Transcrição/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Ovarianas/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Transfecção
9.
Oncogene ; 30(9): 1020-31, 2011 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-20972462

RESUMO

Serous borderline ovarian tumors (SBOTs) are slow-growing, non-invasive ovarian epithelial neoplasms. SBOTs are considered to be distinct entities that give rise to invasive low-grade serous carcinomas (LGCs), which have a relatively poor prognosis and are unrelated to high-grade serous carcinomas (HGCs). The mechanisms underlying the progression of non-invasive SBOTs to invasive epithelial ovarian carcinomas are not understood. We recently established short-term cultures of SBOT cells from tumor biopsies and showed that inactivation of p53, retinoblastoma (Rb) and/or PP2A by the simian virus 40 (SV40) large (LT) and small T antigens extends the life span of the cells and endows them with the ability to invade Matrigel-coated transwells. In this study, we show that concurrent inhibition of p53 and Rb by the SV40 LT produces cells (referred to as SBOT4-LT) with increased life span and cell invasion. To distinguish the roles of p53 and Rb in the progression from SBOTs to invasive ovarian carcinomas, we performed small interfering RNA-mediated knockdown of endogenous p53 in a spontaneously immortalized SBOT cell line, SBOT3.1, which increased cell invasion. This increased invasive activity was associated with the transcriptional downregulation of E-cadherin, correlated with an increase in PIK3CA levels and the increased activation of Akt. Conversely, in invasive LGC-derived MPSC1 cells, enhancing the levels of p53 decreased cell invasion and diminished the phosphatidylinositol 3-kinase (PI3K)/Akt-mediated downregulation of E-cadherin. Inhibition of Rb also enhanced invasiveness, but did not affect the levels of PIK3CA and E-cadherin in SBOT3.1 cells, suggesting that it functions by a different pathway. To our knowledge, this study is the first to show that p53 has an important role in the progression from SBOTs to invasive carcinomas. In addition, our findings suggest that downregulation of E-cadherin by the PI3K/Akt pathway contributes to this progression.


Assuntos
Caderinas/antagonistas & inibidores , Cistadenocarcinoma Seroso/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Antígenos Virais de Tumores/metabolismo , Western Blotting , Carcinoma Epitelial do Ovário , Sobrevivência Celular/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases , Cistadenocarcinoma Seroso/genética , Feminino , Imunofluorescência , Técnicas de Silenciamento de Genes , Humanos , Hibridização In Situ , Invasividade Neoplásica , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , RNA Interferente Pequeno/genética , Proteína do Retinoblastoma/antagonistas & inibidores , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus 40 dos Símios/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
10.
Oncogene ; 30(37): 3930-42, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21478913

RESUMO

The mechanisms underlying the progression of noninvasive serous borderline ovarian tumors (SBOT) to low-grade invasive carcinomas are poorly understood. We recently showed that inhibition of p53 induces SBOT invasion by activating the PI3K/Akt pathway and transcriptionally repressing E-cadherin. In human cancers, aberrant DNA methylation is a common phenomenon, and it is thought to be involved in the progression from noninvasive to invasive ovarian carcinomas. In this study, we tested the hypothesis that inhibition of p53 downregulates E-cadherin by regulating the methylation of its promoter in SBOT cells. Here, we show that DNA methyltransferase-1 (DNMT1), but not DNMT3a or DNMT3b, was increased in SV40 LT-infected SBOT4 cells, SBOT4-LT and the low-grade invasive serous ovarian carcinoma-derived cell line MPSC1. Treatment with 5-Aza-dC, a DNMT1 inhibitor, restored E-cadherin promoter methylation and expression, and inhibited cell invasion in both invasive SBOT4-LT and MPSC1 cells. Moreover, knockdown of endogenous p53 using siRNA in SBOT3.1 cells induced DNMT1 expression and led to an increase in E-cadherin promoter methylation. Additionally, activation of the PI3K/Akt pathway is required for p53 inhibition-induced DNMT1 expression. The increase in DNMT1 was associated with the inhibition of p53-induced downregulation of E-cadherin and cell invasion. Our findings show an important role for p53 in the progression of SBOT to an invasive carcinoma, and suggest that downregulation of E-cadherin by DNMT1-mediated promoter methylation contributes to this process.


Assuntos
Caderinas/genética , Carcinoma/patologia , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/patologia , Proteína Supressora de Tumor p53/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Caderinas/antagonistas & inibidores , Carcinoma/metabolismo , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Decitabina , Feminino , Técnicas de Silenciamento de Genes , Humanos , Invasividade Neoplásica , Neoplasias Ovarianas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , DNA Metiltransferase 3B
11.
Oncogene ; 30(24): 2753-66, 2011 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-21297666

RESUMO

E-cadherin is a cell-cell adhesion protein and tumor suppressor that is silenced in many malignancies. E-cadherin is thought to suppress tumor cell growth by antagonizing ß-catenin signaling. However, the role of E-cadherin in ovarian cancer progression is still controversial. In this study, we showed that loss of E-cadherin induced ovarian cancer cell growth and constitutive activation of phosphoinositide 3-kinase (PI3K)/Akt signaling by the inhibition of phosphatase and tensin homolog (PTEN) transcription through the downregulation of early growth response gene 1 (Egr1). In addition, immunofluorescence microscopy and T-cell factor promoter/luciferase reporter assays showed that E-cadherin loss was associated with enhanced nuclear ß-catenin signaling. Constitutive activation of PI3K/Akt signaling reinforced nuclear ß-catenin signaling by inactivating glycogen synthase kinase-3ß indicating cross-talk between the PI3K/Akt and ß-catenin signaling pathways. Finally, we found that E-cadherin negatively regulates tumor cell growth, in part, by positively regulating PTEN expression via ß-catenin-mediated Egr1 regulation, thus influencing PI3K/Akt signaling. In summary, endogenous E-cadherin inhibits PI3K/Akt signaling by antagonizing ß-catenin-Egr1-mediated repression of PTEN expression. Thus, the loss of E-cadherin itself may contribute to dysregulated PI3K/Akt signaling through its effects on PTEN, or it may exacerbate the frequent activation of PI3K/Akt signaling that occurs as a result of overexpression, mutation and/or amplification.


Assuntos
Caderinas/fisiologia , Proteína 1 de Resposta de Crescimento Precoce/fisiologia , Neoplasias Ovarianas/patologia , PTEN Fosfo-Hidrolase/genética , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , beta Catenina/fisiologia , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , PTEN Fosfo-Hidrolase/fisiologia , Transdução de Sinais , Transcrição Gênica
12.
Oncogene ; 30(26): 2964-74, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21317933

RESUMO

Gonadotropin-releasing hormone (GnRH) is a potent prometastatic factor in ovarian cancer, but the intracellular signaling events are not well understood. The classical Gα(q)-phospholipase C signal transduction pathway known to operate in the pituitary is not involved in GnRH actions at non-pituitary targets. Here we showed that GnRH treatment of ovarian cancer cells led to a rapid and remarkable tyrosine phosphorylation of p120 catenin (p120(ctn)), which was mediated by P-cadherin. The use of P-cadherin small interfering RNA or neutralizing antibodies to inhibit P-cadherin expression and function resulted in diminished p120(ctn) activation, confirming that the effect was P-cadherin specific. On exploring how P-cadherin, which lacks intrinsic kinase activity, might regulate the activation of p120(ctn), we found that P-cadherin could induce the ligand-independent activation of insulin-like growth factor-1 receptor (IGF-1R). Inhibition of IGF-1R expression or its activity significantly inhibited GnRH-induced p120(ctn) activation, and the subsequent cell migration and invasion. In addition, we showed that IGF-1R regulation by P-cadherin was associated with complex formation between IGF-1R and P-cadherin, and this regulation was also observed to be in vivo correlated with metastasis. Furthermore, using a mouse model of ovarian cancer metastasis, GnRH receptor knockdown was shown to diminish peritoneal dissemination of tumors and ascites formation. These findings suggest for the first time that GnRH can initiate an outside-in p120(ctn) signal transduction through the cross-talk between P-cadherin and IGF-1R, thus providing a novel molecular mechanism by which GnRH may control the high level of aggressiveness and invasion and metastasis potential that are characteristic of ovarian cancer.


Assuntos
Caderinas/fisiologia , Carcinoma/patologia , Cateninas/fisiologia , Hormônio Liberador de Gonadotropina/farmacologia , Neoplasias Ovarianas/patologia , Receptor IGF Tipo 1/fisiologia , Animais , Caderinas/antagonistas & inibidores , Caderinas/genética , Carcinoma/genética , Cateninas/genética , Cateninas/metabolismo , Células Cultivadas , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/efeitos adversos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Neoplasias Ovarianas/genética , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/genética , Receptores LHRH/antagonistas & inibidores , Receptores LHRH/genética , Receptores LHRH/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , delta Catenina
13.
Oncogene ; 29(16): 2427-40, 2010 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20118984

RESUMO

Gonadotropin-releasing hormone (GnRH) receptor expression is often elevated in ovarian cancer, but its potential role in ovarian cancer metastasis has just begun to be revealed. Cadherin switching is a crucial step during tumorigenesis, particularly in metastasis. Here, we showed that GnRH is an inducer of E- to P-cadherin switching, which is reminiscent of that seen during ovarian tumor progression. Overexpression of P-cadherin significantly enhanced, whereas knockdown of P-cadherin reduced migration and invasion regardless of E-cadherin expression, suggesting that inappropriate expression of P-cadherin contributes to the invasive phenotype. These effects of P-cadherin were mediated by activation of the Rho GTPases, Rac1, and Cdc42, through accumulation of p120 catenin (p120(ctn)) in the cytoplasm. The use of p120(ctn) small interfering RNA or chimeric cadherin construct to inhibit p120(ctn) expression and cytoplasmic localization, respectively, resulted in significant inhibition of cell migration and invasion, with a concomitant reduction in Rac1 and Cdc42 activation, confirming that the effect was p120(ctn) specific. Similarly, the migratory/invasive phenotype could be reversed by expression of dominant-negative Rac1 and Cdc42. These results identify for the first time cadherin switching and p120(ctn) signaling as important targets of GnRH function and as novel mediators of invasiveness and tumor progression in ovarian cancer.


Assuntos
Caderinas/fisiologia , Cateninas/fisiologia , Hormônio Liberador de Gonadotropina/fisiologia , Neoplasias Ovarianas/patologia , Transdução de Sinais/fisiologia , Proteínas rac1 de Ligação ao GTP/fisiologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Invasividade Neoplásica , Proteína cdc42 de Ligação ao GTP/fisiologia , delta Catenina
14.
Hum Reprod ; 22(1): 63-74, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17067994

RESUMO

BACKGROUND: The restricted expression of ADAMTS-5 (A Disintegrin And Metalloproteinase with ThromboSpondin repeats-5) to the maternal-fetal interface in mice has led to this novel metalloproteinase being assigned the trivial name 'implantin'. METHODS: As a first step in determining whether ADAMTS-5 also contributes to the implantation process in humans, we have examined the spatiotemporal expression of this ADAMTS subtype in the endometrium during the menstrual cycle and pregnancy by immunohistochemical analysis. A quantitative competitive PCR (QC-PCR) strategy and western blotting were subsequently used to determine whether interleukin (IL)-1beta and transforming growth factor (TGF)-beta1, two cytokines involved in the formation of the maternal-fetal interface, were capable of regulating ADAMTS-5 messenger RNA (mRNA) and protein levels in primary cultures of stromal cells isolated from first trimester decidual tissues. RESULTS: ADAMTS-5 expression in the stroma of the human endometrium correlates with decidualization of this cellular compartment in vivo. IL-1beta was found to increase (P < 0.05) whereas TGF-beta1 decreased (P < 0.05) ADAMTS-5 mRNA and protein levels in decidual stromal cell cultures in a concentration- and time-dependent manner. These regulatory effects were attenuated by function-perturbing antibodies directed against either cytokine. CONCLUSIONS: ADAMTS-5 expression is restricted to decidualized stromal cells of the human endometrium in vivo and is subject to regulation by cytokines in vitro.


Assuntos
Proteínas ADAM/biossíntese , Decídua/metabolismo , Interleucina-1beta/farmacologia , Células Estromais/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Proteína ADAMTS5 , Decídua/citologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Ciclo Menstrual , Gravidez , RNA Mensageiro/metabolismo
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