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1.
Eur J Cancer Care (Engl) ; 27(2): e12696, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28440587

RESUMO

Helping breast cancer patients who desire a pregnancy after cancer treatment is a vital issue. Little is known about the complex context of the decision to become pregnant after breast cancer treatment. The purpose of this study was to understand the risk-benefit perception of choosing conception or contraception after treatment in Taiwan. We applied grounded theory to guide this exploratory qualitative study. Data were collected through in-depth interviews with 16 breast cancer patients. Pregnancy was addressed in the context of cancer as a potentially life-threatening diagnosis and its treatment. The verbatim transcriptions were analysed using constant comparative analysis and methods of open, axial and selective coding. The core theme that described the risk perception of pregnancy among patients with breast cancer after treatment focused on "reaching the balance of life." Seven dimensions of risk-benefit perception of pregnancy, including perceived health status, safety, expected gain, harm, loading, support and time were explored among women treated for breast cancer. We found that women treated for breast cancer applied risk-benefit perceptions to decide whether to become pregnant. Implementing contextual counselling could help to decrease perceived barriers to choose pregnancy and increase the quality of pregnancy care.


Assuntos
Neoplasias da Mama/psicologia , Saúde Reprodutiva , Medição de Risco , Sobreviventes , Adulto , Tomada de Decisões , Feminino , Teoria Fundamentada , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Taiwan , Adulto Jovem
2.
J Nutr Health Aging ; 25(1): 134-140, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33367474

RESUMO

OBJECTIVES: The study aimed to develop a brief geriatric assessment (BGA) tool for the general practitioner to evaluate geriatric syndromes in community-dwelling older adults. DESIGN: A cross-sectional study. SETTING: 58 communities from four aging cities in Taiwan. PARTICIPANTS: 1,258 community-dwelling older adults aged 65 years and above. MEASUREMENTS: The BGA targeted physical function impairment, cognitive impairment, and mood impairment. The cutoff values of physical function tests (handgrip strength and 6-meter walk test [6MWT]) were estimated by receiver operating characteristic analysis. Second, the diagnostic validity of the BGA was calculated in terms of sensitivity, specificity, and predictive values, which were compared to corresponding comprehensive geriatric assessment (CGA) items. Third, the associated risk factors of geriatric syndromes were selected using stepwise logistic regression. Finally, we combined items selected from literature and CGA and then proposed a practical BGA framework. RESULTS: The proposed BGA comprised dominant handgrip strength, 6MWT, self-report personal birthday, address, and telephone number, question 'Do you have depressive mood for the past two weeks?', Rinne tuning-fork tests, Snellen scale, and body mass index. It evaluated multidimensional aspects of geriatrics syndromes including physical, cognitive, mood, and sensory impairment, sarcopenia, and nutrition status. Sensitivities in the Taiwan BGA items ranged from 48% for dominant handgrip strength to 97.6% for 6MWT corresponding to physical impairment; 58.3% for cognitive impairment corresponding to Short Portable Mental Status Questionnaire; 62.7% for mood impairment corresponding to Geriatric Depression Scale. The Taiwan BGA for the general practitioner takes less than 10 minutes and is suitable in the community setting. CONCLUSION: Early management of geriatric syndromes in the community is important. The current study demonstrated a practical BGA tool for the general practitioner to comprehensively assess geriatric syndromes in community-dwelling older adults.


Assuntos
Clínicos Gerais/normas , Avaliação Geriátrica/métodos , Vida Independente/normas , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino
3.
J Int Med Res ; 38(4): 1354-64, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20926008

RESUMO

Pilocytic astrocytomas are usually cystic; cyst formation within these tumours may result in increased intracranial pressure, due to the effect of their mass, and contribute to cerebral damage. Eosinophilic granular bodies (EGBs) are produced abundantly in pilocytic astrocytomas but their role in disease progression remains unknown. Immunohistochemistry studies showed EGBs to exhibit pronounced reactivity to antibodies against lysosome-associated membrane proteins (LAMP)-1 and LAMP-2, and the lysosomal enzyme cathepsin D. Both LAMP-1 and LAMP-2 showed peripheral rim and granular staining patterns. The EGBs were scattered widely across cysts and, where EGBs aggregated in clusters, were usually close to areas of fluid in the cysts. Most EGBs had nuclei either attached or close by, indicating that the EGBs may be derived from anucleated astrocytes. The results suggest that EGBs, together with other factors, may play a role in the development of cysts in pilocytic astrocytomas.


Assuntos
Astrocitoma/complicações , Catepsina D/metabolismo , Cistos/complicações , Grânulos Citoplasmáticos/enzimologia , Eosinófilos/enzimologia , Proteínas de Membrana Lisossomal/metabolismo , Adolescente , Adulto , Astrocitoma/enzimologia , Astrocitoma/patologia , Cistos/enzimologia , Cistos/patologia , Grânulos Citoplasmáticos/patologia , Feminino , Humanos , Imuno-Histoquímica , Proteína 2 de Membrana Associada ao Lisossomo , Masculino , Adulto Jovem
4.
B-ENT ; 6(1): 53-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20420081

RESUMO

Pleomorphic adenoma of the nasal septum presents a clinical diagnostic challenge. We report a rare case of pleomorphic adenoma of the nasal septum in a 39-year-old woman with a 1-month history of nasal obstruction. Wide surgical excision is the recommended treatment for this tumour.


Assuntos
Adenoma Pleomorfo/cirurgia , Septo Nasal , Neoplasias Nasais/cirurgia , Adenoma Pleomorfo/patologia , Adulto , Feminino , Humanos , Neoplasias Nasais/patologia
5.
Endocrinology ; 142(4): 1554-60, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11250936

RESUMO

ATP has been shown to activate the phospholipase C/diacylglycerol/protein kinase C (PKC) pathway. However, little is known about the downstream signaling events. The present study was designed to examine the effect of ATP on activation of the mitogen-activated protein kinase (MAPK) signaling pathway and its physiological role in human granulosa-luteal cells. Western blot analysis, using a monoclonal antibody that detected the phosphorylated forms of extracellular signal-regulated kinase-1 and -2 (p42(mapk) and p44 (mapk), respectively), demonstrated that ATP activated MAPK in a dose- and time-dependent manner. Treatment of the cells with suramin (a P2 purinoceptor antagonist), neomycin (a phospholipase C inhibitor), staurosporin (a PKC inhibitor), or PD98059 (an MAPK/ERK kinase inhibitor) significantly attenuated the ATP-induced activation of MAPK. In contrast, ATP-induced MAPK activation was not significantly affected by pertussis toxin (a G(i) inhibitor). To examine the role of G(s) protein, the intracellular cAMP level was determined after treatment with ATP or hCG. No significant elevation of intracellular cAMP was noted after ATP treatment. To determine the role of MAPK in steroidogenesis, human granulosa-luteal cells were treated with ATP, hCG, or ATP plus hCG in the presence or absence of PD98059. RIA revealed that ATP alone did not significantly affect the basal progesterone concentration. However, hCG-induced progesterone production was reduced by ATP treatment. PD98059 reversed the inhibitory effect of ATP on hCG-induced progesterone production. To our knowledge, this is the first demonstration of ATP-induced activation of the MAPK signaling pathway in the human ovary. These results support the idea that the MAPK signaling pathway is involved in mediating ATP actions in the human ovary.


Assuntos
Trifosfato de Adenosina/fisiologia , Corpo Lúteo/enzimologia , Células da Granulosa/enzimologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Adulto , Western Blotting , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/citologia , AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Toxina Pertussis , Gravidez , Progesterona/metabolismo , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Antagonistas do Receptor Purinérgico P2 , Radioimunoensaio , Receptores Purinérgicos P2/metabolismo , Fatores de Virulência de Bordetella/farmacologia
6.
Endocrinology ; 142(6): 2351-60, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356682

RESUMO

Most epithelial ovarian tumors appear to arise from the ovarian surface epithelium (OSE). Even though it has been suggested that estrogen may be associated with ovarian tumorigenesis, the exact role of estrogen in the regulation of apoptosis in neoplastic OSE cells remains uncertain. Immortalized OSE (IOSE) cell lines were generated from human normal OSE. These cell lines represent early neoplastic (IOSE-29), tumorigenic (IOSE-29EC), and late neoplastic (IOSE-29EC/T4 and IOSE-29EC/T5) transformation stages from human normal OSE. The present studies demonstrated that both mRNAs and proteins of estrogen receptor (ER) alpha and beta were expressed in IOSE cell lines. No difference was observed in normal OSE and IOSE-29 cells, whereas treatment with 17beta-estradiol (E(2); 10(-8)-10(-6) M) resulted in an increased thymidine incorporation and DNA content per culture in IOSE-29EC cells. This effect of E(2) was attenuated with tamoxifen treatment (10(-6) M), the estrogen antagonist, suggesting that the effect of E(2) is mediated through specific ERs. There was no stimulatory effect on thymidine incorporation before day 6, but after 6 days of E(2) treatment, thymidine incorporation was significantly increased. Because the ratio of thymidine incorporation to DNA content per culture did not change, this E(2) effect does not appear to indicate stimulation of proliferation but, rather, inhibition of apoptosis. In addition, treatment with tamoxifen (10(-6) M) induced apoptosis up to 3-fold in IOSE-29EC cells, whereas cotreatment with E(2) (10(-8)-10(-6) M) plus tamoxifen attenuated tamoxifen-induced apoptosis in a dose-dependent manner. Both proapoptotic bax and antiapoptotic bcl-2 at messenger RNA (mRNA) and protein levels were expressed in IOSE cell lines. Interestingly, treatments with E(2) resulted in a significant increase of bcl-2 mRNA and protein levels (2- and 1.7-fold, respectively), whereas no difference was observed in bax mRNA level. Thus, E(2) may enhance survival of IOSE-29EC by up-regulating bcl-2, and antiapoptotic bcl-2 may be a dominant regulator of apoptotic pathway in these cells. In conclusion, the present study indicates that early neoplastic (IOSE-29), tumorigenic (IOSE-29EC), and late neoplastic (IOSE-29EC/T4 and T5) OSE cells expressed both ERalpha and ERbeta at the mRNA and protein levels. In addition, E(2) prevented tamoxifen induced-apoptosis through ERs. The mechanism of E(2) action may be associated with up-regulation of bcl-2 gene at mRNA and protein levels. These results suggest that estrogen may play a role in ovarian tumorigenesis by preventing apoptosis in tumorigenic OSE cells.


Assuntos
Apoptose/genética , Estradiol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Neoplasias Ovarianas/química , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/genética , Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Células Epiteliais/química , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Feminino , Humanos , Neoplasias Ovarianas/patologia , RNA Mensageiro/análise , Receptores de Estrogênio/análise , Receptores de Estrogênio/genética , Células Tumorais Cultivadas
7.
Endocrinology ; 142(1): 182-92, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11145581

RESUMO

Until recently, the primate brain was thought to contain only one form of GnRH known as mammalian GnRH (GnRH-I). The recent cloning of a second form of GnRH (GnRH-II) with characteristics of chicken GnRH-II in the primate brain has prompted a reevaluation of the role of GnRH in reproductive functions. In the present study, we investigated the hormonal regulation of GnRH-II messenger RNA (mRNA) and its functional role in the human granulosa-luteal cells (hGLCs), and we provided novel evidence for differential hormonal regulation of GnRH-II vs. GnRH-I mRNA expression. Human GLCs were treated with various concentrations of GnRH-II, GnRH-II agonist (GnRH-II-a), or GnRH-I agonist (GnRH-I-a; leuprolide) in the absence or presence of FSH or human CG (hCG). The expression levels of GnRH-II, GnRH-I, and GnRH receptor (GnRHR) mRNA were investigated using semiquantitative or competitive RT-PCR. A significant decrease in GnRH-II and GnRHR mRNA levels was observed in cells treated with GnRH-II or GnRH-II-a. In contrast, GnRH-I-a revealed a biphasic effect (up- and down-regulation) of GnRH-I and GnRHR mRNA, suggesting that GnRH-I and GnRH-II may differentially regulate GnRHR and their ligands (GnRH-I and GnRH-II). Treatment with FSH or hCG increased GnRH-II mRNA levels but decreased GnRH-I mRNA levels, further indicating that GnRH-I and GnRH-II mRNA levels are differentially regulated. To investigate the physiological role of GnRH-II, hGLCs were treated with GnRH-II or GnRH-II-a in the presence or absence of hCG, for 24 h, and progesterone secretion was measured by RIA. Both GnRH-II and GnRH-II-a inhibited basal and hCG-stimulated progesterone secretion, effects which were similar to the effects of GnRH-I treatment on ovarian steroidogenesis. Next, hGLCs were treated with various concentrations of GnRH-II, GnRH-II-a, or GnRH-I-a; and the expression levels of FSH receptor and LH receptor were investigated using semiquantitative RT-PCR. A significant down-regulation of FSH receptor and LH receptor was observed in cells treated with GnRH-II, GnRH-II-a, and GnRH-I-a, demonstrating that GnRH-II and GnRH-I may exert their antigonadotropic effect by down-regulating gonadotropin receptors. Interestingly, GnRH-II and GnRH-II-a did not affect basal and hCG-stimulated intracellular cAMP accumulation, suggesting that the antigonadotropic effect of GnRH-II may be independent of modulation of cAMP levels. Taken together, these results suggest that GnRH-II may have biological effects similar to those of GnRH-I but is under differential hormonal regulation in the human ovary.


Assuntos
Corpo Lúteo/fisiologia , Regulação da Expressão Gênica , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/genética , Células da Granulosa/fisiologia , Transcrição Gênica , Animais , Células Cultivadas , Galinhas , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/citologia , Corpo Lúteo/efeitos dos fármacos , Feminino , Células da Granulosa/citologia , Células da Granulosa/efeitos dos fármacos , Humanos , Progesterona/metabolismo , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Receptores do FSH/genética , Receptores LHRH/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Endocrinology ; 142(2): 580-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159828

RESUMO

In the present study, we investigated the expression of estrogen receptors (ERalpha and ERbeta) in human ovarian surface epithelial (hOSE) cells and the ovarian cancer cell line, OVCAR-3, and provided novel evidence that estrogen may have a growth regulatory effect in these cells. Expression levels of ERalpha messenger RNA (mRNA) were 1.5-fold higher in OVCAR-3 cells than in hOSE cells, as revealed by semiquantitative RT-PCR and Southern blot analysis. A significant increase (3.3-fold) in ERss mRNA levels was observed in OVCAR-3 cells compared with hOSE cells. In parallel with mRNA levels, expression levels of ERalpha and ERbeta proteins were also higher in OVCAR-3 cells compared with hOSE cells. We recently proposed that GnRH and its receptor may have an autocrine role in hOSE and ovarian cancer cells. To determine whether estrogen regulates GnRH and GnRH receptor (GnRHR), hOSE and OVCAR-3 cells were treated with various concentrations of 17beta-estradiol for 24 h. Expression levels of GnRH and GnRHR mRNA were examined using quantitative and competitive RT-PCR, respectively. Treatment with 17beta-estradiol induced a significant down-regulation of GnRH mRNA in OVCAR-3 cells, but not in hOSE cells and of GnRHR mRNA in both hOSE and OVCAR-3 cells. Tamoxifen, an estrogen antagonist, prevented the effects of 17ssestradiol, suggesting that estradiol action is mediated via the ER. Finally, the effect of estrogen on the growth of hOSE and OVCAR-3 cells was investigated. The cells were treated with various concentrations of 17ss-estradiol, and the proliferative index of cells was measured using [(3)H]thymidine incorporation and DNA fluorometric assays. 17beta-Estradiol stimulated the growth of OVCAR-3 cells in a dose- and time-dependent manner. In contrast, 17beta-estradiol failed to stimulate the growth of hOSE cells. As estrogen down-regulated GnRH and GnRHR mRNA, we investigated whether estrogen treatment blocks the growth inhibitory effect of a GnRH agonist in OVCAR-3 and hOSE cells. Cells were treated with 17beta-estradiol (10(-7) M) together with (D-Ala(6))-GnRH (10(-7) M), and the proliferative index of cells was measured. Pre- or cotreatment of cells with 17beta-estradiol significantly attenuated the growth inhibitory effect of the GnRH agonist in OVCAR-3 cells, whereas no effect of 17ss-estradiol treatment was observed in hOSE cells. To our knowledge, these results provide the first demonstration of a potential interaction between the estradiol/ER and GnRH/GnRHR systems, which may be important in the growth regulation of normal and neoplastic hOSE cells.


Assuntos
Estradiol/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Inibidores do Crescimento/farmacologia , Neoplasias Ovarianas/patologia , Ovário/citologia , Receptores LHRH/metabolismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/genética , Inibidores do Crescimento/antagonistas & inibidores , Humanos , Neoplasias Ovarianas/genética , Ovário/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores LHRH/genética
9.
Endocrinology ; 142(2): 671-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159838

RESUMO

The present study investigated the activation of mitogen-activated protein kinases (MAPKs) by a GnRH agonist (GnRHa) in human granulosa-luteal cells (hGLCs). The phosphorylation state of p44 and p42 MAPK was examined using antibodies that distinguish phospho-p44/42 MAPK (Thr(202)/Tyr(204)) from total p44/42 MAPK (activated plus inactivated). Activation of MAPK by GnRHa was observed within 5 min and was sustained for 60 min after treatment. GnRHa stimulated MAPK activation in a dose-dependent manner, with maximum stimulation (6.7-fold over basal levels) at 10(-7) M. Pretreatment with a protein kinase C (PKC) inhibitor, GF109203X, completely blocked GnRHa-induced MAPK activation. In addition, pretreatment with a PKC activator, phorbol-12-myristate 13-acetate, potentiated GnRH-induced MAPK activation. These results indicate that GnRHa stimulates MAPK activation through a PKC-dependent pathway in hGLCs, possibly coupled to G(q)alpha protein. MAPK activation was also observed in response to 8-bromo-cAMP or cholera toxin, but not pertussis toxin. Forskolin (50 microM) substantially stimulated a rapid cAMP accumulation, whereas GnRHa (10(-7) M) or pertussis toxin (100 mg/ml) did not affect basal intracellular cAMP levels. Cotreatment of GnRHa (10(-7) M) did not attenuate forskolin- or hCG-stimulated cAMP accumulation. These results suggest that the GnRH receptor is probably not coupled to G(s)alpha or G(i)alpha in hGLCs. Finally, GnRHa (10(-7) M) stimulated a significant increase in Elk-1 phosphorylation and c-fos messenger RNA expression, as revealed by an in vitro kinase assay and Northern blot analysis, respectively. These results clearly demonstrate that GnRH activates the MAPK cascade through a PKC-dependent pathway in the human ovary.


Assuntos
Corpo Lúteo/enzimologia , Proteínas de Ligação a DNA , Hormônio Liberador de Gonadotropina/farmacologia , Células da Granulosa/enzimologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fatores de Transcrição , Células Cultivadas , Toxina da Cólera/farmacologia , Colforsina/farmacologia , Corpo Lúteo/citologia , AMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Antagonistas de Hormônios/farmacologia , Humanos , Oligopeptídeos/farmacologia , Toxina Pertussis , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Virulência de Bordetella/farmacologia , Proteínas Elk-1 do Domínio ets
10.
J Clin Endocrinol Metab ; 86(2): 773-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158045

RESUMO

ATP has been shown to modulate progesterone production in human granulosa-luteal cells (hGLCs) in vitro. After binding to a G protein-coupled P2 purinergic receptor, ATP stimulates phospholipase C. The resultant production of diacylglycerol and inositol triphosphate activates protein kinase C (PKC) and intracellular calcium [Ca(2+)](i) mobilization, respectively. In the present study, we examined the potential cross-talk between the PKC and Ca(2+) pathway in ATP signal transduction. Specifically, the effect of PKC on regulating ATP-evoked [Ca(2+)](i) oscillations were examined in hGLCs. Using microspectrofluorimetry, [Ca(2+)](i) oscillations were detected in Fura-2 loaded hGLCs in primary culture. The amplitudes of the ATP-triggered [Ca(2+)](i) oscillations were reduced in a dose-dependent manner by pretreating the cells with various concentrations (1 nM to 10 microM) of the PKC activator, phorbol-12-myristate-13-acetate (PMA). A 10 microM concentration of PMA completely suppressed 10 microM ATP-induced oscillations. The inhibitory effect occurred even when PMA was given during the plateau phase of ATP evoked [Ca(2+)](i) oscillations, suggesting that extracellular calcium influx was inhibited. The role of PKC was further substantiated by the observation that, in the presence of a PKC inhibitor, bisindolylmaleimide I, ATP-induced [Ca(2+)](i) oscillations were not completely suppressed by PMA. Furthermore, homologous desensitization of ATP-induced calcium oscillations was partially reversed by bisindolylmaleimide I, suggesting that activated PKC may be involved in the mechanism of desensitization. These results demonstrate that PKC negatively regulates the ATP-evoked [Ca(2+)](i) mobilization from both intracellular stores and extracellular influx in hGLCs and further support a modulatory role of ATP and P2 purinoceptor in ovarian steroidogenesis.


Assuntos
Trifosfato de Adenosina/farmacologia , Cálcio/fisiologia , Corpo Lúteo/fisiologia , Células da Granulosa/fisiologia , Proteína Quinase C/metabolismo , Células Cultivadas , Corpo Lúteo/citologia , Citosol/metabolismo , Diglicerídeos/metabolismo , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Cinética , Modelos Biológicos , Oscilometria , Acetato de Tetradecanoilforbol/farmacologia
11.
J Clin Endocrinol Metab ; 86(7): 3237-42, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11443195

RESUMO

The presence of P2U purinoceptor in human granulosa-luteal cells (hGLCs) indicates a potential role of ATP in regulating ovarian function. In this study an inhibitory effect of ATP on hCG-induced cAMP production was observed. Extracellular ATP has been shown to activate protein kinase C (PKC) after binding to a purinoceptor. To understand the role of PKC in mediating ATP action, hCG-stimulated cAMP level was examined in the presence of the PKC activator, 1 micromol/L phorbol 12-myristate 13-acetate (PMA), or the PKC inhibitor, 1 micromol/L staurosporin or 1 micromol/L bisindolylmaleimide I. PMA, like 10 micromol/L ATP, significantly reduced hCG-evoked cAMP production. In addition, the inhibitory effect of ATP was reversed by staurosporin and bisindolylmaleimide I. To further investigate the involvement of PKC isoforms in mediating the inhibitory effect of ATP, the presence of PKC isoforms in cultured hGLCs was examined by Western blot using monoclonal antibodies against specific isoforms. Translocation of PKC isoforms from cytosolic fraction to membrane fraction was studied to identify the active PKC isozymes subsequent to ATP treatment. The change in PKC isoform in PKC-depleted cells (achieved by exposure to PMA for 18 h) was also examined. Our results demonstrated the presence of PKCalpha, -delta, -iota, and -lambda isoforms in hGLCs and the translocation of PKCalpha subsequent to ATP treatment. In PKC-depleted cells the PKCalpha level was reduced, and no significant effect of ATP on hCG-stimulated cAMP production was observed. To our knowledge, this is the first demonstration of PKC isoforms in hGLCs and the involvement of activated PKC in mediating the antigonadotropic effect of extracellular ATP. Taken together, these results further support a role of this neurotransmitter in regulating human ovarian function.


Assuntos
Trifosfato de Adenosina/farmacologia , Gonadotropina Coriônica/antagonistas & inibidores , Células da Granulosa/metabolismo , Isoenzimas/metabolismo , Células Lúteas/metabolismo , Proteína Quinase C/metabolismo , Western Blotting , Membrana Celular/enzimologia , Células Cultivadas , Gonadotropina Coriônica/farmacologia , AMP Cíclico/metabolismo , Citosol/enzimologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Indóis/farmacologia , Células Lúteas/efeitos dos fármacos , Maleimidas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Estaurosporina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia
12.
J Clin Endocrinol Metab ; 86(5): 2125-35, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11344217

RESUMO

Most ovarian neoplasms arise from the ovarian surface epithelium (OSE), and multiple growth factors have been implicated to influence the transformation from OSE. The present study was performed to investigate the role of activin and transforming growth factor-beta (TGFbeta) in normal and neoplastic OSE cells. An immortalized OSE cell line (IOSE-29) was generated from normal OSE by transfecting simian virus 40 large T antigen and was rendered tumorigenic after subsequent transfection with the E-cadherin gene (IOSE-29EC). The activin/inhibin subunits and activin receptors were expressed at both messenger ribonucleic acids and protein levels in these cells, suggesting that activin may have an autocrine role in neoplastic OSE cells. Treatments with activin (1-100 ng/mL) resulted in a significant decrease in cell proliferation in both IOSE-29 and IOSE-29EC cells, although we have shown that it stimulated the growth of ovarian cancer cells and had no effect on normal OSE. This inhibitory effect was attenuated with cotreatment with follistatin. Treatment with TGFbeta (0.1-10 ng/mL) also significantly decreased the proliferation of normal, IOSE-29, and IOSE-29EC cells in a dose-dependent manner. In addition, treatments with both activin and TGFbeta resulted in an increase in DNA fragmentation in IOSE-29EC cells in a dose-dependent manner. This apoptotic effect of activin was attenuated by cotreatment with follistatin. Treatment with TGFbeta (1 and 10 ng/mL) resulted in a significant decrease in Bcl-2 protein (up to 50%) in IOSE-29EC, whereas no difference was observed in Bax protein levels. Therefore, down-regulated Bcl-2 by TGFbeta may eventually induce apoptosis in IOSE-29EC cells. In contrast, no difference was observed in Bax and Bcl-2 protein expression after treatment with activin. In conclusion, the present study indicates that activin and TGFbeta inhibited growth and induced apoptosis in early neoplastic (IOSE-29) and tumorigenic OSE (IOSE-29EC) cells. Furthermore, antiapoptotic Bcl-2 protein was down-regulated by TGFbeta, whereas no difference was produced in Bax protein by activin or TGFbeta treatment or in Bcl-2 protein by activin. These results suggest that activin and TGFbeta may play a role in growth inhibition and induction of apoptosis in early neoplastic and tumorigenic stage of ovarian cancer.


Assuntos
Apoptose/efeitos dos fármacos , Inibinas/farmacologia , Neoplasias Ovarianas/patologia , Fator de Crescimento Transformador beta/farmacologia , Receptores de Ativinas , Ativinas , Linhagem Celular , Feminino , Humanos , Inibinas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , RNA Mensageiro/análise , Receptores de Fatores de Crescimento/análise , Receptores de Fatores de Crescimento/genética , Fator de Crescimento Transformador beta/genética , Proteína X Associada a bcl-2
13.
J Clin Endocrinol Metab ; 86(1): 375-80, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11232027

RESUMO

In the ovary it has been demonstrated that PGF(2alpha) activates the phospholipase C (PLC)/diacylglycerol/protein kinase C pathway. However, little is known about the downstream signaling events that mediate subsequent cellular responses such as steroidogenesis. The present study was designed to examine the effect of PGF(2alpha) on activation of the mitogen-activated protein kinase (MAPK) signaling pathway and its physiological role in human granulosa-luteal cells (hGLCs). Human GLCs, obtained from women undergoing in vitro fertilization-embryo transfer, were treated with increasing concentrations of PGF(2alpha) (10 nmol/L to 10 micromol/L) for 5 min. For time-course experiments, hGLCs were treated with 1 micromol/L PGF(2alpha) for 1, 5, 10, or 20 min. Western blot analysis, using a monoclonal antibody that detected the phosphorylated forms of extracellular signal-regulated kinases 1 and 2 (p42(mapk) and p44(mapk), respectively), demonstrated that PGF(2alpha) activated MAPK in hGLCs in a dose- and time-dependent manner. Treatment of the cells with neomycin (10 mmol/L; a PLC inhibitor), bisindolylmaleimide I (5 micromol/L; a PKC inhibitor), or PD98059 (50 micromol/L; a MEK inhibitor and a MAPK kinase inhibitor) significantly attenuated the PGF(2alpha)-induced activation of MAPK. In contrast, MAPK activation was not significantly affected by pertussis toxin (200 ng/mL; a G(i) inhibitor) pretreatment. To determine the role of MAPK in steroidogenesis, hGLCs were treated with PGF(2alpha) (1 micromol/L), hCG (1 IU/mL), or PGF(2alpha) plus hCG in the presence or absence of PD98059. Progesterone levels in the culture medium were examined by RIA. Treatment of hGLCs with PGF(2alpha) significantly inhibited hCG-induced progesterone production. The presence of the MEK inhibitor, PD98059, reversed the inhibitory effect of PGF(2alpha) on hCG-induced progesterone production. To our knowledge, it is the first demonstration of PGF(2alpha)-induced activation of the MAPK signaling pathway in the human ovary. These results indicated that PGF(2alpha) activated MAPK subsequent to PLC and PKC activation through pertussis toxin-insensitive G protein in hGLCs. Further, we demonstrated that PGF(2alpha)-induced MAPK activation is associated with modulation of progesterone production. These results support the idea that the MAPK signaling pathway is involved in mediating PGF(2alpha) actions in the human ovary.


Assuntos
Corpo Lúteo/efeitos dos fármacos , Dinoprosta/farmacologia , Células da Granulosa/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/citologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Feminino , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Toxina Pertussis , Progesterona/biossíntese , Proteína Quinase C/fisiologia , Fosfolipases Tipo C/fisiologia , Fatores de Virulência de Bordetella/farmacologia
14.
J Clin Endocrinol Metab ; 86(10): 4789-97, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11600542

RESUMO

The direct involvement of melatonin in modulation of ovarian steroidogenesis, the high levels of melatonin found in human follicular fluid, and the presence of melatonin binding sites in the ovary led us to hypothesize that melatonin acts as a modulator of ovarian function. In contrast to the hypothalamus and pituitary, the mechanism of melatonin action at the level of the ovary is still poorly understood. In the present study, we investigated the gene expression of the two different forms of melatonin receptors in human granulosa-luteal cells, using RT-PCR. PCR products corresponding to the expected sizes of the melatonin receptor subtypes, mt(1)-R and MT(2)-R, were obtained from granulosa-luteal cells, and the authenticity of the PCR products was confirmed by Southern blot hybridization with cDNA probes. Subsequent cloning and sequence analysis revealed that the ovarian mt(1)-R and MT(2)-R cDNAs are identical to their brain counterparts. Because gonadotropins and GnRH acting through specific receptors in the human ovary regulate cellular functions, we investigated the role of melatonin in the regulation of FSH receptor, LH receptor, GnRH, and GnRH receptor levels. Treatment with melatonin (10 pM-100 nM) significantly increased LH receptor mRNA levels without altering the expression of the FSH receptor gene. Both GnRH and GnRH receptor mRNA levels were significantly decreased, to 61% and 45% of control levels, respectively, after melatonin treatment. Melatonin treatment alone had no effect on basal progesterone production but enhanced the effects of human CG-stimulated progesterone production. Because MAPKs are activated in response to a diverse array of extracellular stimuli leading to the regulation of cell growth, division, and differentiation, and because melatonin has been shown to modulate cellular proliferation and differentiation, in this study, we demonstrated that melatonin activated MAPK in a dose- and time-dependent manner. In summary, our studies demonstrate, for the first time, that melatonin can regulate progesterone production, LH receptor, GnRH, and GnRH receptor gene expression through melatonin receptors in human granulosa-luteal cells, which may be mediated via the MAPK pathway and activation of Elk-1. Our results support the notion that melatonin plays a direct role in regulating ovarian function.


Assuntos
Proteínas de Ligação a DNA , Células da Granulosa/efeitos dos fármacos , Melatonina/farmacologia , Fatores de Transcrição , Células Cultivadas , Feminino , Hormônio Liberador de Gonadotropina/análise , Hormônio Liberador de Gonadotropina/genética , Células da Granulosa/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Reação em Cadeia da Polimerase , Progesterona/biossíntese , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/análise , Receptores de Superfície Celular/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores do FSH/análise , Receptores do FSH/genética , Receptores do LH/análise , Receptores do LH/genética , Receptores LHRH/análise , Receptores LHRH/genética , Receptores de Melatonina , Transdução de Sinais , Proteínas Elk-1 do Domínio ets
15.
J Clin Endocrinol Metab ; 85(4): 1591-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10770202

RESUMO

The P2U purinoceptor (P2UR) has been identified pharmacologically in the ovary. However, the expression and regulation of the P2UR messenger RNA (mRNA) in human ovarian cells are still poorly characterized. The present study was designed to examine the expression and regulation of the P2UR in human granulosa-luteal cells (hGLCs) by RT-PCR and Northern blot analysis. A PCR product corresponding to the expected 599-bp P2UR complementary DNA was obtained from hGLCs. Molecular cloning and sequencing of the PCR product revealed an identical sequence to the reported P2UR complementary DNA. Two mRNA transcripts of 2.0 kb and 4.6 kb were identified in hGLCs using Northern blot analysis. The expression of the P2UR mRNA was down-regulated by human CG in a dose- and time-dependent manner. Treatment with 8-bromo-cAMP and forskolin also attenuated P2UR mRNA levels. Calcium signaling following the activation of the P2UR in single hGLCs was studied using microspectrofluorimetry. It revealed that, like ATP, uridine triphosphate (UTP) also induced cytosolic calcium mobilization in a dose-dependent manner. These results demonstrate for the first time that the P2UR mRNA is expressed in hGLCs and that P2UR mRNA is regulated by human CG, cAMP, and forskolin. The P2UR expressed in hGLCs functional because activation of the P2UR by ATP or UTP resulted in rapid and transient mobilization of cytosolic calcium at the single cell level. These findings further support a potential role of this neurotransmitter receptor in the human ovary.


Assuntos
Regulação da Expressão Gênica , Células da Granulosa/metabolismo , Células Lúteas/metabolismo , Receptores Purinérgicos P2/genética , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Trifosfato de Adenosina/farmacologia , Northern Blotting , Cálcio/metabolismo , Gonadotropina Coriônica/farmacologia , Clonagem Molecular , Colforsina/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , RNA Mensageiro/análise , Receptores Purinérgicos P2Y2 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Transdução de Sinais , Uridina Trifosfato/farmacologia
16.
Mol Cell Endocrinol ; 170(1-2): 143-51, 2000 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-11162898

RESUMO

Considering that the action of gonadotropin-releasing hormone (GnRH) may be mediated via different signaling pathways in extrapituitary tissues, in the present study we investigated the role of the human GnRH receptor (GnRHR) in activating mitogen-activated protein kinases (MAPKs), which regulate cell growth, division, and differentiation. The phosphorylation state of p44 and p42 MAPKs was examined using antibodies that distinguish phospho-p44/42 MAPK (P-MAPK, Thr(202)/Tyr(204)) from total p44/42 MAPK (T-MAPK, activated plus inactivated) in human ovarian and placental cells. Cell cultures were treated with various concentrations of a GnRH agonist, (D-Ala(6))-GnRH, for 5 min. (D-Ala(6))-GnRH stimulated a rapid activation of P-MAPK in human granulosa-luteal cells (hGLCs) and immortalized extravillous trophoblast (IEVT) cells. Interestingly, (D-Ala(6))-GnRH treatment of ovarian cancer (OVCAR-3) and placental carcinoma (JEG-3) cells induced a biphasic regulatory pattern in P-MAPK activity. In contrast, no change of T-MAPK levels was observed following addition of the GnRH agonist in the ovarian and placental cells examined. The physiological implication of MAPK activation by GnRH in the ovarian and placental cells was also investigated. Human GLCs were treated with (D-Ala(6))-GnRH for 24 h, and progesterone secretion was measured by an established RIA. (D-Ala(6))-GnRH induced a significant decrease in progesterone secretion with maximum inhibition (a 45% decrease over basal level) at 10(-7) M. This inhibitory effect was completely reversed by pretreatment with MAPK/ERK kinase 1 (MEK1) inhibitor (PD98059), suggesting the involvement of the MAPK pathway in hGLCs. Placental JEG-3 cells were treated with (D-Ala(6))-GnRH for 24 h, and betahCG mRNA level was measured using Northern blot analysis. (D-Ala(6))-GnRH stimulated the expression of betahCG mRNA to 160% of control value in JEG-3 cells. In contrast to the ovarian cells, pretreatment of JEG-3 cells with PD98059 failed to block the stimulatory effect of GnRH on betahCG mRNA level, suggesting that other signaling pathway(s) may play a more dominant role in GnRH-induced betahCG mRNA expression. To our knowledge, this is the first demonstration that (1) GnRH induces activation of the MAPK signaling pathway in normal and carcinoma cells of the human ovary and placenta, and (2) MAPK mediates the direct action of GnRH on progesterone production in hGLCs.


Assuntos
Hormônio Liberador de Gonadotropina/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ovário/citologia , Placenta/citologia , Animais , Gonadotropina Coriônica/efeitos dos fármacos , Gonadotropina Coriônica/genética , Relação Dose-Resposta a Droga , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Humanos , Immunoblotting , Camundongos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Ovário/enzimologia , Ovário/metabolismo , Hipófise/citologia , Placenta/enzimologia , Placenta/metabolismo , Progesterona/metabolismo , RNA Mensageiro/efeitos dos fármacos , Trofoblastos/citologia , Células Tumorais Cultivadas
17.
Leuk Lymphoma ; 42(1-2): 207-14, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11699208

RESUMO

Lymphomas of mucosa-associated lymphoid tissue (MALT) are a distinct subgroup of extranodal B-cell non-Hodgkin's lymphomas. Most studies have failed to demonstrate the clonal rearrangement of BCL-1, BCL-2 or c-MYC genes for MALT lymphomas. Further, alteration of the p53 gene is rarely demonstrated in low-grade MALT lymphomas, but can be detected in high-grade disease. Lymphomas of the ocular adnexa represent approximately eight percent of all extranodal lymphomas, most of which are MALT lymphomas, but few studies had explored the alterations of BCL-1, BCL-2, c-MYC and p53 genes specifically for ocular MALT lymphomas. We investigated the changes to BCL-1, BCL-2, c-MYC and p53 genes in these lymphomas for Taiwanese patients. Clonal rearrangement for immunoglobulin heavy-chain (IgH), BCL-1, BCL-2, c-MYC and p53 genes was examined for 16 cases of ocular MALT lymphoma. Restriction-length polymorphism and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) of the DNA, corresponding to exons 5 through 9, followed by DNA sequencing, were utilized to analyze the possible mutations of the p53 gene for these tumors. Thirteen of the cases revealed rearranged IgH genes using Southern blotting or PCR. No rearrangement of BCL-1, BCL-2, c-MYC or p53 genes was discovered, with point mutation of the p53 gene in one case. As for other types of MALT lymphomas, BCL-1, BCL-2 and c-MYC genes are not implicated in the pathogenesis of the ocular sub-group. Although alteration of the p53 gene is rare for low-grade ocular MALT lymphoma, its role in disease progression merits further research.


Assuntos
Neoplasias Oculares/genética , Linfoma de Zona Marginal Tipo Células B/genética , Adolescente , Adulto , Idoso , Análise Mutacional de DNA , Neoplasias Oculares/etiologia , Feminino , Rearranjo Gênico , Genes de Imunoglobulinas , Genes bcl-1 , Genes bcl-2 , Genes myc , Genes p53 , Humanos , Linfoma de Zona Marginal Tipo Células B/etiologia , Masculino , Pessoa de Meia-Idade , Taiwan
18.
Neoplasma ; 49(4): 251-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12382024

RESUMO

We compared the effectiveness technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) of head and neck in evaluating cervical lymph node (LN) metastasis in nasopharyngeal carcinomas (NPC). Forty NPC patients with cervical LN metastases confirmed histopathologically underwent Te-99m MIBI SPECT and MRI of the head and neck to evaluate cervical LN metastases. For 16 LN lesions with discordant results between Tc-99m MIBI SPECT and MRI, Tc-99m MIBI SPECT could correctly detect 1 metastatic and 10 benign LN lesions as well as MRI could correctly detect 3 metastatic and 2 benign LN lesions. Agreement positive results of Tc-99m MIBI SPECT and MRI could correctly detect all of the remaining 24 metastatic LN lesions. Tc-99m MIBI SPECT has a better specificity but a lower sensitivity for detecting cervical LN metastases in NPC when compared with MRI. The combined use of Tc-99m MIBI SPECT and MRI could increase the accuracy compared with the single use of either Te-99m MIBI SPECT or MRI to detect cervical LN metastases in NPC.


Assuntos
Carcinoma/diagnóstico , Carcinoma/secundário , Imageamento por Ressonância Magnética/métodos , Neoplasias Nasofaríngeas/patologia , Tecnécio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Carcinoma/diagnóstico por imagem , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Pescoço/diagnóstico por imagem , Pescoço/patologia , Nitrilas
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