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1.
Hematol Oncol ; 41(2): 248-256, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34472655

RESUMEN

This retrospective cohort study aimed to evaluate primary treatment and recent survival trends in patients with primary diffuse large B-cell lymphoma of central nervous system (CNS) from 1995 to 2016. Using the SEER data, patients diagnosed with non-HIV-associated primary central nervous system lymphoma (PCNSL)-diffuse large B-cell lymphoma (DLBCL) aged ⩾18 years between 1995 and 2016 were identified. The year of diagnosis was divided into the time period-1 (1995-2002), the time period-2 (2003-2012), and the time period-3 (2013-2016). Chi-square tests, the Kaplan-Meier method, log-rank test, and Cox regression model were used in the analysis. Overall, 3760 patients were included. Both the use of radiotherapy alone and the application of combined chemoradiotherapy decreased significantly, following the wider use of chemotherapy alone during 1995-2016. There was a significant improvement in PCNSL cause-specific survival (CSS) (period-1: 13 months vs. period-2: 19 months vs. period-3: 41 months, p < 0.001). Survival of patients aged above 70 years did not change from the time period-1 to the time period-2 (p = 0.101). However, there was an increase in CSS from the time period-2 to the time period-3 in the elderly patients (period-2: 5 months vs. period-3: 9 months, p < 0.001). On multivariable analyses, diagnosed in the time period-3 was significantly and independently associated with better CSS (hazard ratio 0.577, 95% confidence interval 0.506-0.659, p < 0.001). Our analysis shows the use of radiotherapy in the treatment of PCNSL has waned over the study span. There was a significant improvement in CSS during 1995-2016, which reflected developments in treatment over time. The elderly patient population also gained a significant CSS benefit in the most recent period.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Linfoma de Células B Grandes Difuso , Linfoma no Hodgkin , Anciano , Humanos , Estudios Retrospectivos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Sistema Nervioso Central/patología
2.
J Org Chem ; 88(6): 3499-3508, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36891880

RESUMEN

Rh(III)-catalyzed C-H/N-H annulation and C-H allylation of phenylindazolones have been realized by employing 5-methylene-1,3-dioxan-2-one and 4-vinyl-1,3-dioxolan-2-one as scalable cross-coupling partners, delivering functionalized indazolone fused heterocycles and branched and linear allyl indazolones respectively in moderate to high yield. These divergent synthesis protocols showcase mild conditions, broad substrate scope, and high functional-group compatibility. In addition, scale-up synthesis and preliminary mechanistic exploratory were also accomplished.

3.
J Org Chem ; 88(9): 5512-5519, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37011236

RESUMEN

The indole-substituted trifluoromethyl sulfonium ylide has been developed via Cp*Rh(III)-catalyzed diazo-carbenoid addition to trifluoromethylthioether and is the first example of an Rh(III)-catalyzed diazo-carbenoid addition reaction with trifluoromethylthioether. Several kinds of indole-substituted trifluoromethyl sulfonium ylide were constructed under mild reaction conditions. The reported method exhibited high functional group compatibility and broad substrate scope. In addition, the protocol was found to be complementary to the method disclosed by a Rh(II) catalyst.

4.
Org Biomol Chem ; 20(25): 5055-5059, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35695281

RESUMEN

Herein, we report a Rh(III)-catalyzed C4-selective activation of indoles by using iodonium ylides as carbene precursors. This protocol proceeded under redox neutral reaction conditions and provided important coupling products with good tolerance of functional groups and high yields. In addition, one-pot synthesis and scale-up and mechanistic studies were also conducted.


Asunto(s)
Rodio , Catálisis , Indoles , Oxidación-Reducción
5.
J Org Chem ; 86(23): 17063-17070, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34797073

RESUMEN

A tandem rhodium(III)-catalyzed system was established to access 3,4-dihydroisoquinolin-1(2H)-one by coupling of N-methoxy-3-methylbenzamide with 2-methylidenetrimethylene carbonate. This one-pot synthesis protocol processed smoothly under mild reaction conditions. Moreover, a total of 28 examples, broad substrate scope, and high functional-group compatibility were observed. Preliminary mechanism studies were also conducted and demonstrated that the rhodium(III) catalyst played a vital role in the C-H-allylation and N-alkylation cyclization process.


Asunto(s)
Rodio , Alquilación , Carbonatos , Catálisis , Ciclización
6.
Acta Pharmacol Sin ; 40(4): 522-529, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29921888

RESUMEN

Silkworm cocoon was recorded to cure carbuncle in the Compendium of Materia Medica. Previous studies have demonstrated that the supplemental silk protein sericin exhibits anticancer activity. In the present study, we investigated the effects of silk fibroin peptide (SFP) extracted from silkworm cocoons against human lung cancer cells in vitro and in vivo and its possible anticancer mechanisms. SFP that we prepared had high content of glycine (~ 30%) and showed a molecular weight of ~ 10 kDa. Intragastric administration of SFP (30 g/kg/d) for 14 days did not affect the weights, vital signs, routine blood indices, and blood biochemical parameters in mice. MTT assay showed that SFP dose-dependently inhibited the growth of human lung cancer A549 and H460 cells in vitro with IC50 values of 9.921 and 9.083 mg/mL, respectively. SFP also dose-dependently suppressed the clonogenic activity of the two cell lines. In lung cancer H460 xenograft mice, intraperitoneal injection of SFP (200 or 500 mg/kg/d) for 40 days significantly suppressed the tumor growth, but did not induce significant changes in the body weight. We further examined the effects of SFP on cell cycle and apoptosis in H460 cells using flow cytometry, which revealed that SFP-induced cell cycle arrest at the S phase, and then promoted cell apoptosis. We demonstrated that SFP (20-50 mg/mL) dose-dependently downregulates Bcl-2 protein expression and upregulates Bax protein in H460 cells during cell apoptosis. The results suggest that SFP should be studied further as a novel therapeutic agent for the treatment of lung cancer.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Fibroínas/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Péptidos/farmacología , Células A549 , Animales , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Fibroínas/química , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Péptidos/química , Relación Estructura-Actividad
7.
Org Lett ; 25(28): 5185-5190, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37439552

RESUMEN

Cp*Rh(III)-catalyzed nitro-directed C-H alkylation/alkenylation of nitroarenes has been reported for the first time. This protocol is associated with the features of high efficiency, broad substrate scope, and good functional group compatibility. Additionally, gram-scale experiments and synthetic applications proved the practicability of the method. Moreover, preliminary mechanistic investigations consistently revealed C-H bond cleavage as the rate-limiting step.

8.
Org Lett ; 25(23): 4286-4291, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37265108

RESUMEN

Two categories of tetrasubstituted phenols were prepared via the cycloaddition reaction of vinyl sulfoxonnium ylides with cyclopropenones in a switchable manner. Copper carbenoid was proposed as the active intermediate in the process of 2,3,4,5-tetrasubstituted phenols formation, while 2,3,5,6-tetrasubstituted phenols were generated via the direct [3 + 3] annulation of vinyl sulfoxonnium ylides with cyclopropenones under metal-free conditions. Further synthetic applications were also demonstrated.


Asunto(s)
Cobre , Metales , Catálisis , Reacción de Cicloadición
9.
Org Lett ; 25(28): 5179-5184, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37415264

RESUMEN

Rh (III)-catalyzed dienylation and cyclopropylation of 1,2,3-benzotriazinones with alkylidenecyclopropanes (ACPs) has been achieved. Different from the previous reports of 1,2,3-benzotriazinones, the triazinone ring remained intact in this C-H bond functionlization reaction. Also, the denitrogenative cyclopropylation could also be realized by changing the reaction temperature. This protocol is featured with high E selectivity, wide substrate scope, and divergent structures of products.

10.
Org Lett ; 23(15): 5719-5723, 2021 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-34286981

RESUMEN

A rhodium(III)-catalyzed C-H allylation of (hetero)arenes by using 2-methylidenetrimethylene carbonate as an efficient allylic source has been developed for the first time. Five different directing groups including oxime, N-nitroso, purine, pyridine, and pyrimidine were compatible, delivering various branched allylarenes bearing an allylic hydroxyl group in moderate to excellent yields.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(9): 2413-6, 2010 Sep.
Artículo en Zh | MEDLINE | ID: mdl-21105408

RESUMEN

The optical characteristics of chromophoric dissolved organic matter (CDOM) were determined in rain samples collected in Xiamen Island, during a rainy season in 2007, using fluorescence excitation-emission matrix spectroscopy associated with UV-Vis absorbance spectra. Results showed that the absorbance spectra of CDOM in rain samples decreased exponentially with wavelength. The absorbance coefficient at 300 nm [a(300)] ranged from 0.27 to 3.45 m(-1), which would be used as an index of CDOM abundance, and the mean value was 1.08 m(-1). The content of earlier stage of precipitation events was higher than that of later stage of precipitation events, which implied that anthropogenic sources or atmospheric pollution or air mass types were important contributors to CDOM levels in precipitation. EEMs spectra showed 4 types of fluorescence signals (2 humic-like fluorescence peaks and 2 protein-like fluorescence peaks) in rainwater samples, and there were significant positive correlations of peak A with C and peak B with S, showing their same sources or some relationship of the two humic-like substance and the two protein-like substance. The strong positive correlations of the two humic-like fluorescence peaks with a(300), suggested that the chromophores responsible for absorbance might be the same as fluorophores responsible for fluorescence. Results showed that the presence of highly absorbing and fluorescing CDOM in rainwater is of significant importance in atmospheric chemistry and might play a previously unrecognized role in the wavelength dependent spectral attenuation of solar radiation by atmospheric waters.

12.
Cell Rep ; 32(12): 108181, 2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32966797

RESUMEN

Hemopexin (Hx) is a scavenger of labile heme. Herein, we present data defining the role of tumor stroma-expressed Hx in suppressing cancer progression. Labile heme and Hx levels are inversely correlated in the plasma of patients with prostate cancer (PCa). Further, low expression of Hx in PCa biopsies characterizes poorly differentiated tumors and correlates with earlier time to relapse. Significantly, heme promotes tumor growth and metastases in an orthotopic murine model of PCa, with the most aggressive phenotype detected in mice lacking Hx. Mechanistically, labile heme accumulates in the nucleus and modulates specific gene expression via interacting with guanine quadruplex (G4) DNA structures to promote PCa growth. We identify c-MYC as a heme:G4-regulated gene and a major player in heme-driven cancer progression. Collectively, these results reveal that sequestration of labile heme by Hx may block heme-driven tumor growth and metastases, suggesting a potential strategy to prevent and/or arrest cancer dissemination.


Asunto(s)
Hemo/metabolismo , Hemopexina/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Ciclo Celular , Línea Celular Tumoral , Núcleo Celular/metabolismo , Proliferación Celular , ADN/genética , Progresión de la Enfermedad , G-Cuádruplex , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Metástasis de la Neoplasia , Fenotipo , Regiones Promotoras Genéticas/genética , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Resultado del Tratamiento , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
13.
Mol Cell Biol ; 26(3): 929-39, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16428447

RESUMEN

Androgen receptor (AR) interacts with beta-catenin and can suppress its coactivation of T cell factor 4 (Tcf4) in prostate cancer (PCa) cells. Pin1 is a peptidyl-prolyl cis/trans isomerase that stabilizes beta-catenin by inhibiting its binding to the adenomatous polyposis coli gene product and subsequent glycogen synthase kinase 3beta (GSK-3beta)-dependent degradation. Higher Pin1 expression in primary PCa is correlated with disease recurrence, and this study found that Pin1 expression was markedly increased in metastatic PCa. Consistent with this result, increased expression of Pin1 in transfected LNCaP PCa cells strongly accelerated tumor growth in vivo in immunodeficient mice. Pin1 expression in LNCaP cells enhanced beta-catenin/Tcf4 transcriptional activity, as assessed using Tcf4-regulated reporter genes, and increased expression of endogenous Tcf4 and c-myc. However, in contrast to results in cells with intact PTEN and active GSK-3beta, Pin1 expression in LNCaP PCa cells, which are PTEN deficient, did not increase beta-catenin. Instead, Pin1 expression markedly inhibited the beta-catenin interaction with AR, and Pin1 abrogated the ability of AR to antagonize beta-catenin/Tcf4 binding and transcriptional activity. These findings demonstrate that AR can suppress beta-catenin signaling, that the AR-beta-catenin interaction can be regulated by Pin1, and that abrogation of this interaction can enhance beta-catenin/Tcf4 signaling and contribute to aggressive biological behavior in PCa.


Asunto(s)
Antagonistas de Receptores Androgénicos , Isomerasa de Peptidilprolil/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , beta Catenina/antagonistas & inhibidores , Animales , Genes Reporteros , Humanos , Luciferasas/análisis , Luciferasas/genética , Masculino , Ratones , Ratones SCID , Mutación , Peptidilprolil Isomerasa de Interacción con NIMA , Metástasis de la Neoplasia , Fosfohidrolasa PTEN/genética , Isomerasa de Peptidilprolil/genética , Estructura Terciaria de Proteína , Receptores Androgénicos/metabolismo , Transducción de Señal , Factores de Transcripción TCF/metabolismo , Proteína 2 Similar al Factor de Transcripción 7 , Transcripción Genética , Transfección , beta Catenina/metabolismo
14.
Mol Endocrinol ; 21(8): 1835-46, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17505060

RESUMEN

Androgens and the androgen receptor (AR) act in cells by modulating gene expression. Through gene microarray studies, we have identified Ets Variant Gene 1 (ETV1) as a novel androgen-regulated gene. Our data demonstrate that ETV1 mRNA and protein are up-regulated in response to ligand-activated AR in androgen-dependent LNCaP cells, but there is no detectable ETV1 expression in normal prostate cells. The ETV1 promoter is induced by androgens and recruits the AR in the context of chromatin. ETV1-regulated endogenous matrix metalloproteinase genes can be induced by ligand-activated AR. In contrast to the hormone-induced expression in androgen-dependent LNCaP cells, ETV1 expression in androgen-independent LNCaP cells is high and unresponsive to androgen. This androgen-independent ETV1 expression contrasts with the hormone-dependent expression observed for TMPRSS2 in these androgen-independent prostate cancer cells. ETV1 is overexpressed in prostate cancer independent of the TMPRSS2:ETV1 translocation. Disruption of ETV1 expression in both androgen-dependent and androgen-independent prostate cancer cells significantly compromises the invasion capacity of these cells, suggesting an important role for ETV1 in prostate cancer metastasis. Collectively, these results demonstrate that ETV1 expression transitions from androgen-induced to androgen-independent as prostate cancer cells switch from hormone-dependent to hormone-refractory and suggest that this transition may be in part responsible for the elevated levels of ETV1 observed in prostate tumors. Additionally, our data provide an indirect mechanism of AR regulation of gene expression, via the transactivation of the transcription factor ETV1.


Asunto(s)
Proteínas de Unión al ADN/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Receptores Androgénicos/fisiología , Factores de Transcripción/genética , Andrógenos/fisiología , Línea Celular Tumoral , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/fisiología , Dihidrotestosterona/metabolismo , Humanos , Masculino , Invasividad Neoplásica , Regiones Promotoras Genéticas , Neoplasias de la Próstata/genética , Transducción de Señal/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/fisiología
15.
Cancer Res ; 66(15): 7783-92, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16885382

RESUMEN

Androgen receptor (AR) plays a central role in prostate cancer, with most tumors responding to androgen deprivation therapies, but the molecular basis for this androgen dependence has not been determined. Androgen [5alpha-dihydrotestosterone (DHT)] stimulation of LNCaP prostate cancer cells, which have constitutive phosphatidylinositol 3-kinase (PI3K)/Akt pathway activation due to PTEN loss, caused increased expression of cyclin D1, D2, and D3 proteins, retinoblastoma protein hyperphosphorylation, and cell cycle progression. However, cyclin D1 and D2 message levels were unchanged, indicating that the increases in cyclin D proteins were mediated by a post-transcriptional mechanism. This mechanism was identified as mammalian target of rapamycin (mTOR) activation. DHT treatment increased mTOR activity as assessed by phosphorylation of the downstream targets p70 S6 kinase and 4E-BP1, and mTOR inhibition with rapamycin blocked the DHT-stimulated increase in cyclin D proteins. Significantly, DHT stimulation of mTOR was not mediated through activation of the PI3K/Akt or mitogen-activated protein kinase/p90 ribosomal S6 kinase pathways and subsequent tuberous sclerosis complex 2/tuberin inactivation or by suppression of AMP-activated protein kinase. In contrast, mTOR activation by DHT was dependent on AR-stimulated mRNA synthesis. Oligonucleotide microarrays showed that DHT-stimulated rapid increases in multiple genes that regulate nutrient availability, including transporters for amino acids and other organic ions. These results indicate that a critical function of AR in PTEN-deficient prostate cancer cells is to support the pathologic activation of mTOR, possibly by increasing the expression of proteins that enhance nutrient availability and thereby prevent feedback inhibition of mTOR.


Asunto(s)
Ciclinas/biosíntesis , Dihidrotestosterona/farmacología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Quinasas/metabolismo , Receptores Androgénicos/metabolismo , Proteínas Quinasas Activadas por AMP , Procesos de Crecimiento Celular/fisiología , Línea Celular Tumoral , Ciclina D , Activación Enzimática , Humanos , Masculino , Complejos Multienzimáticos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteínas Quinasas S6 Ribosómicas , Serina-Treonina Quinasas TOR
17.
Mol Endocrinol ; 18(10): 2388-401, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15256534

RESUMEN

Prostate cancers respond to treatments that suppress androgen receptor (AR) function, with bicalutamide, flutamide, and cyproterone acetate (CPA) being AR antagonists in clinical use. As CPA has substantial agonist activity, it was examined to identify AR coactivator/corepressor interactions that may mediate androgen-stimulated prostate cancer growth. The CPA-liganded AR was coactivated by steroid receptor coactivator-1 (SRC-1) but did not mediate N-C terminal interactions or recruit beta-catenin, indicating a nonagonist conformation. Nonetheless, CPA did not enhance AR interaction with nuclear receptor corepressor, whereas the AR antagonist RU486 (mifepristone) strongly stimulated AR-nuclear receptor corepressor binding. The role of coactivators was further assessed with a T877A AR mutation, found in LNCaP prostate cancer cells, which converts hydroxyflutamide (HF, the active flutamide metabolite) into an agonist that stimulates LNCaP cell growth. The HF and CPA-liganded T877A ARs were coactivated by SRC-1, but only the HF-liganded T877A AR was coactivated by beta-catenin. L-39, a novel AR antagonist that transcriptionally activates the T877A AR, but still inhibits LNCaP growth, similarly mediated recruitment of SRC-1 and not beta-catenin. In contrast, beta-catenin coactivated a bicalutamide-responsive mutant AR (W741C) isolated from a bicalutamide-stimulated LNCaP subline, further implicating beta-catenin recruitment in AR-stimulated growth. Androgen-stimulated prostate-specific antigen gene expression in LNCaP cells could be modulated by beta-catenin, and endogenous c-myc expression was repressed by dihydrotestosterone, but not CPA. These results indicate that interactions between AR and beta-catenin contribute to prostate cell growth in vivo, although specific growth promoting genes positively regulated by AR recruitment of beta-catenin remain to be identified.


Asunto(s)
Proteínas del Citoesqueleto/fisiología , Neoplasias de la Próstata/patología , Receptores Androgénicos/fisiología , Transactivadores/fisiología , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular Tumoral , Proteínas del Citoesqueleto/genética , Dihidrotestosterona/farmacología , Humanos , Masculino , Reacción en Cadena de la Polimerasa/métodos , ARN Interferente Pequeño/genética , Receptores Androgénicos/genética , Transactivadores/genética , Transfección , beta Catenina
18.
PLoS One ; 8(11): e79573, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24260253

RESUMEN

Taxane based chemotherapy is the standard of care treatment in castration resistant prostate cancer (CRPC). There is convincing evidence that taxane therapy affects androgen receptor (AR) but the exact mechanisms have to be further elucidated. Our studies identified c-jun as a crucial key player which interacts with AR and thus determines the outcome of the taxane therapy given. Docetaxel (Doc) and paclitaxel (Pac) agents showed different effects on LNCaP and LNb4 evidenced by alteration in the protein and mRNA levels of c-jun, AR and PSA. Docetaxel-induced phophorylation of c-jun occurred before JNK phosphorylation which suggests that c-jun phosphorylation is independent of JNK pathways in prostate cancer cells. A xenograft study showed that mice treated with Pac and bicalutamide showed worse outcome supporting our hypothesis that upregulation of c-jun might act as a potent antiapoptotic factor. We observed in our in vitro studies an inverse regulation of PSA- and AR-mRNA levels in Doc treated LNb4 cells. This was also seen for kallikrein 2 (KLK 2) which followed the same pattern. Given the fact that response to taxane therapy is measured by PSA decrease we have to consider that this might not reflect the true activity of AR in CRPC patients.


Asunto(s)
Hidrocarburos Aromáticos con Puentes/farmacología , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-jun/metabolismo , Receptores Androgénicos/metabolismo , Taxoides/farmacología , Taxoides/uso terapéutico , Anilidas/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citometría de Flujo , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Desnudos , Nitrilos/uso terapéutico , Unión Proteica , Proteínas Proto-Oncogénicas c-jun/genética , ARN Interferente Pequeño , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Androgénicos/genética , Compuestos de Tosilo/uso terapéutico
19.
J Mol Endocrinol ; 41(1): 13-23, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18469090

RESUMEN

Cellular changes that affect the androgen receptor (AR) can cause prostate cancer to transition from androgen dependent to androgen independent, which is usually lethal. One common change in prostate tumors is overexpression of the AR, which has been shown to lead to androgen-independent growth of prostate cancer cells. This led us to hypothesize that expression of a hyperactive AR would be sufficient for androgen-independent growth of prostate cancer cells. To test this hypothesis, stable lune cancer prostate (LNCaP) cell lines were generated, which express a virion phosphoprotein (VP)16-AR hybrid protein that contains full-length AR fused to the strong viral transcriptional activation domain VP16. This fusion protein elicited as much as a 20-fold stronger transcriptional activity than the natural AR. Stable expression of VP16-AR in LNCaP cells yielded androgen-independent cell proliferation, while under the same growth conditions the parental LNCaP cells exhibited only androgen-dependent growth. These results show that expression of a hyperactive AR is sufficient for androgen-independent growth of prostate cancer cells. To study the molecular basis of this enhanced growth, we measured the expression of soluble guanylyl cyclase-alpha1 (sGCalpha1), a subunit of the sGC, an androgen-regulated gene that has been shown to be involved in prostate cancer cell growth. Interestingly, the expression of sGCalpha1 is androgen independent in VP16-AR-expressing cells, in contrast to its androgen-induced expression in control LNCaP cells. RNA(I)-dependent inhibition of sGCalpha1 expression resulted in significantly reduced proliferation of VP16-AR cells, implicating an important role for sGCalpha1 in the androgen-independent growth of these cells.


Asunto(s)
Andrógenos/fisiología , Proliferación Celular , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Receptores Androgénicos/biosíntesis , Receptores Androgénicos/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Masculino , Receptores Androgénicos/fisiología , Transcripción Genética
20.
Huan Jing Ke Xue ; 28(8): 1788-95, 2007 Aug.
Artículo en Zh | MEDLINE | ID: mdl-17926412

RESUMEN

Mussels have been proposed as appropriate biomonitors of marine pollution, especially for monitoring metallic pollution based on variations of metallothionein as biomarkers. Under 2 exposure levels (12.7 microg/L, 63.5 microg/L), Cu accumulation and metallothionein-like protein (MTLP) induction by mussel (Perna viridis) digestive glands were investigated and simulated into dynamic models in the present work, and the soluble and total Cu burden of digestive glands were also determined. Calculated mean Cu uptake rates by mussel target organ were 2.045 and 7.028 microg x (g x d)(-1) respectively, and the theoretical equilibrium kinetic BCFs of Cu were 2074 and 1619 correspondingly. And within the exposure duration, different changing trends of ratio of soluble Cu to total Cu in digestive glands were observed in the two groups. The MTLP level of control samples was (0.551 +/- 0.037) mg/g, and the counterparts are 0.407 - 0.699 mg/g, 0.826 - 0.942 mg/g respectively when mussels were exposed to 12.7 microg/L and 63.5 microg/L Cu solutions. Statistically significant MTLP induction (p < 0.001) was observed under higher exposure level. MTLP contents in digestive glands increased with the exposure Cu concentration and body accumulation of metal. There is a significantly negative exponential rise relationship (p < 0.000 1) between MTLP and Cu concentrations accumulated in the digestive glands of mussels.


Asunto(s)
Bivalvos/metabolismo , Cobre/farmacocinética , Metalotioneína/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Animales , Bivalvos/efectos de los fármacos , Cobre/metabolismo , Cobre/toxicidad , Sistema Digestivo/efectos de los fármacos , Sistema Digestivo/metabolismo , Exposición a Riesgos Ambientales/análisis , Distribución Tisular , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad
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