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1.
Artículo en Inglés | MEDLINE | ID: mdl-32990356

RESUMEN

Deep-penetration fluorescence imaging in the second near-infrared (NIR-II) window heralds a new era of clinical surgery, in which high-resolution vascular/lymphatic anatomy and detailed cancerous tissues can be visualized in real time. Described here is a series of polymethine-based semiconducting polymers with intrinsic emission maxima in the NIR-IIa (1300-1400 nm) window and absorption maxima ranging from 1082 to 1290 nm. These polymers were prepared as semiconducting polymer dots (Pdots) in aqueous solutions with fluorescence quantum yields of 0.05-0.18 %, and they demonstrate promising applications in noninvasive through-skull brain imaging in live mice with remarkable spatial resolution as well as signal-to-background contrast. This study offers a platform for future design of NIR-IIa or even NIR-IIb emitting Pdots.

2.
Anal Chem ; 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31815438

RESUMEN

There have been enormous efforts for developing the next generations of fluorometric lateral flow immunochromatographic strip (ICTS) owing to the great advances in fluorescent materials in these years. Here we developed one type of fluorometric ICTS based on ultrabright semiconducting polymer dots (Pdots) in which the traffic light-like signals were created by energy transfer depending on the target concentration. This platform was successfully applied for qualitatively rapid screening and quantitatively precise analysis of prostate-specific antigen (PSA) in 10 min from merely one drop of the whole blood sample. This FRET-created traffic light ICTS possesses excellent specificity and an outstanding detection sensitivity of 0.32 ng/mL for PSA. Moreover, we conducted proof-of-concept experiments to demonstrate its potential for multiplexed detection of cancer biomarkers at the same time in an individual test strip by taking advantage of the traffic light signals. To the best of our knowledge, it is the first model of a traffic light-like immunoassay test strip based on Pdots with multiplexing ability. These results would pave an avenue for designing the next generation of point-of-care diagnostics.

3.
ACS Pharmacol Transl Sci ; 2(6): 453-467, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-32259077

RESUMEN

Inhibition of the androgen receptor (AR) is the mainstay treatment for advanced prostate cancer. Ralaniten (formally EPI-002) prevents AR transcriptional activity by binding to its N-terminal domain (NTD) which is essential for transcriptional activity. Ralaniten acetate (EPI-506) the triacetate pro-drug of ralaniten, remains the only AR-NTD inhibitor to have entered clinical trials (NCT02606123). While well tolerated, the trial was ultimately terminated due to poor pharmacokinetic properties and resulting pill burden. Here we discovered that ralaniten was glucuronidated which resulted in decreased potency. Long-term treatment of prostate cancer cells with ralaniten results in upregulation of UGT2B enzymes with concomitant loss of potency. This has proven to be a useful model with which to facilitate the development of more potent second-generation AR-NTD inhibitors. Glucuronidated metabolites of ralaniten were also detected in the serum of patients in Phase 1 clinical trials. Therefore, we tested an analogue of ralaniten (EPI-045) which was resistant to glucuronidation and demonstrated superiority to ralaniten in our resistant model. These data support that analogues of ralaniten designed to mitigate glucuronidation may optimize clinical responses to AR-NTD inhibitors.

4.
Cancer Cell ; 32(4): 474-489.e6, 2017 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-29017058

RESUMEN

Androgen receptor (AR) signaling is a distinctive feature of prostate carcinoma (PC) and represents the major therapeutic target for treating metastatic prostate cancer (mPC). Though highly effective, AR antagonism can produce tumors that bypass a functional requirement for AR, often through neuroendocrine (NE) transdifferentiation. Through the molecular assessment of mPCs over two decades, we find a phenotypic shift has occurred in mPC with the emergence of an AR-null NE-null phenotype. These "double-negative" PCs are notable for elevated FGF and MAPK pathway activity, which can bypass AR dependence. Pharmacological inhibitors of MAPK or FGFR repressed the growth of double-negative PCs in vitro and in vivo. Our results indicate that FGF/MAPK blockade may be particularly efficacious against mPCs with an AR-null phenotype.


Asunto(s)
Factores de Crecimiento de Fibroblastos/fisiología , Neoplasias de la Próstata/patología , Receptores Androgénicos/fisiología , Transducción de Señal/fisiología , Antagonistas de Andrógenos/uso terapéutico , Animales , Diferenciación Celular , Línea Celular Tumoral , Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Humanos , Proteína 1 Inhibidora de la Diferenciación/fisiología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Metástasis de la Neoplasia , Neoplasias de la Próstata/tratamiento farmacológico , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptores de Factores de Crecimiento de Fibroblastos/fisiología
5.
PLoS One ; 12(3): e0173632, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28328957

RESUMEN

Helicobacter pylori neutrophil-activating protein (HP-NAP) is involved in H. pylori-associated gastric inflammation. HP-NAP is also a vaccine candidate, a possible drug target, and a potential diagnostic marker for H. pylori-associated diseases. Previously, we purified recombinant HP-NAP by one-step diethylaminoethyl (DEAE) negative mode chromatography by collecting the unbound fraction at pH 8.0 at 4°C. It remains unclear why HP-NAP does not bind to DEAE resins at the pH above its isoelectric point during the purification. To investigate how pH affects the surface net charge of HP-NAP and its binding to DEAE resins during the purification, recombinant HP-NAP expressed in Escherichia coli was subjected to DEAE negative mode chromatography at pH ranging from 7.0 to 9.0 at 25°C and the surface charge of purified HP-NAP was determined by capillary electrophoresis. A minimal amount of HP-NAP was detected in the elution fraction of DEAE Sepharose resin at pH 8.5, whereas recombinant HP-NAP was detected in the elution fraction of DEAE Sephadex resin only at pH 7.0 and 8.0. The purified recombinant HP-NAP obtained from the unbound fractions was not able to bind to DEAE resins at pH 7.0 to 9.0. In addition, the surface charge of the purified HP-NAP was neutral at pH 7.0 to 8.0 and was either neutral or slightly negative at pH 8.5 and 9.0. However, recombinant HP-NAP purified from gel-filtration chromatography was able to bind to DEAE Sepharose resin at pH 7.0 to 9.0 and DEAE Sephadex resin at pH 7.0. At pH 8.5 and 9.0, only the negatively charged species of HP-NAP were found. Thus, recombinant HP-NAP with different charge status can be differentially purified by DEAE negative mode chromatography and gel-filtration chromatography. Furthermore, the charge distribution on the surface of HP-NAP, the presence of impure proteins, and the overall net charge of the resins all affect the binding of HP-NAP to DEAE resins during the negative purification.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Helicobacter pylori/química , Proteínas Bacterianas/inmunología , Cromatografía en Gel , Cromatografía por Intercambio Iónico , DEAE Dextrano , Electroquímica , Electroforesis Capilar , Etanolaminas , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Helicobacter pylori/patogenicidad , Humanos , Concentración de Iones de Hidrógeno , Resinas de Intercambio Iónico , Neutrófilos/inmunología , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Sefarosa
6.
J Biol Chem ; 291(42): 22231-22243, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27576691

RESUMEN

Androgen receptor (AR) is a validated drug target for all stages of prostate cancer including metastatic castration-resistant prostate cancer (CRPC). All current hormone therapies for CRPC target the C-terminal ligand-binding domain of AR and ultimately all fail with resumed AR transcriptional activity. Within the AR N-terminal domain (NTD) is activation function-1 (AF-1) that is essential for AR transcriptional activity. Inhibitors of AR AF-1 would potentially block most AR mechanisms of resistance including constitutively active AR splice variants that lack the ligand-binding domain. Here we provide evidence that sintokamide A (SINT1) binds AR AF-1 region to specifically inhibit transactivation of AR NTD. Consistent with SINT1 targeting AR AF-1, it attenuated transcriptional activities of both full-length AR and constitutively active AR splice variants, which correlated with inhibition of growth of enzalutamide-resistant prostate cancer cells expressing AR splice variants. In vivo, SINT1 caused regression of CRPC xenografts and reduced expression of prostate-specific antigen, a gene transcriptionally regulated by AR. Inhibition of AR activity by SINT1 was additive to EPI-002, a known AR AF-1 inhibitor that is in clinical trials (NCT02606123). This implies that SINT1 binds to a site on AF-1 that is unique from EPI. Consistent with this suggestion, these two compounds showed differences in blocking AR interaction with STAT3. This work provides evidence that the intrinsically disordered NTD of AR is druggable and that SINT1 analogs may provide a novel scaffold for drug development for the treatment of prostate cancer or other diseases of the AR axis.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas de Neoplasias , Neoplasias de la Próstata , Pirrolidinonas/farmacología , Receptores Androgénicos/biosíntesis , Activación Transcripcional/efectos de los fármacos , Animales , Línea Celular Tumoral , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Dominios Proteicos , Pirrolidinonas/farmacocinética , Factor de Transcripción STAT3/metabolismo
7.
J Vis Exp ; (112)2016 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-27404433

RESUMEN

Helicobacter pylori neutrophil-activating protein (HP-NAP) is a major virulence factor of Helicobacter pylori (H. pylori). It plays a critical role in H. pylori-induced gastric inflammation by activating several innate leukocytes including neutrophils, monocytes, and mast cells. The immunogenic and immunomodulatory properties of HP-NAP make it a potential diagnostic and vaccine candidate for H. pylori and a new drug candidate for cancer therapy. In order to obtain substantial quantities of purified HP-NAP used for its clinical applications, an efficient method to purify this protein with high yield and purity needs to be established. In this protocol, we have described a method for one-step negative chromatographic purification of recombinant HP-NAP overexpressed in Escherichia coli (E. coli) by using diethylaminoethyl (DEAE) ion-exchange resins (e.g., Sephadex) in batch mode. Recombinant HP-NAP constitutes nearly 70% of the total protein in E. coli and is almost fully recovered in the soluble fraction upon cell lysis at pH 9.0. Under the optimal condition at pH 8.0, the majority of HP-NAP is recovered in the unbound fraction while the endogenous proteins from E. coli are efficiently removed by the resin. This purification method using negative mode batch chromatography with DEAE ion-exchange resins yields functional HP-NAP from E. coli in its native form with high yield and purity. The purified HP-NAP could be further utilized for the prevention, treatment, and prognosis of H. pylori-associated diseases as well as cancer therapy.


Asunto(s)
Helicobacter pylori , Neutrófilos , Proteínas Bacterianas , Cromatografía , Escherichia coli , Monocitos
8.
Clin Cancer Res ; 22(17): 4466-77, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27140928

RESUMEN

PURPOSE: Persistent androgen receptor (AR) transcriptional activity is clinically evident in castration-resistant prostate cancer (CRPC). Therefore, AR remains as a viable therapeutic target for CRPC. All current hormonal therapies target the C-terminus ligand-binding domain (LBD) of AR. By using EPI to target AR activation function-1 (AF-1), in the N-terminal domain that is essential for AR transactivation, we evaluate the ability of EPI to overcome several clinically relevant AR-related mechanisms of resistance. EXPERIMENTAL DESIGN: To study the effect of EPI on AR transcriptional activity against overexpressed coactivators, such as SRC1-3 and p300, luciferase reporter assays were performed using LNCaP cells. AR-negative COS-1 cells were employed for reporter assays to examine whether the length of polyglutamine tract affects inhibition by EPI. The effect of EPI on constitutively active AR splice variants was studied in LNCaP95 cells, which express AR-V7 variant. To evaluate the effect of EPI on the proliferation of LNCaP95 cells, we performed in vitro BrdUrd incorporation assay and in vivo studies using xenografts in mice. RESULTS: EPI effectively overcame several molecular alterations underlying aberrant AR activity, including overexpressed coactivators, AR gain-of-function mutations, and constitutively active AR-V7. EPI inhibited AR transcriptional activity regardless of the length of polyglutamine tract. Importantly, EPI significantly inhibited the in vitro and in vivo proliferation of LNCaP95 prostate cancer cells, which are androgen independent and enzalutamide resistant. CONCLUSIONS: These findings support EPI as a promising therapeutic agent to treat CRPC, particularly against tumors driven by constitutively active AR splice variants that are resistant to LBD-targeting drugs. Clin Cancer Res; 22(17); 4466-77. ©2016 AACRSee related commentary by Sharp et al., p. 4280.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Compuestos de Bencidrilo/farmacología , Clorhidrinas/farmacología , Resistencia a Antineoplásicos , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Mutación , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Unión Proteica , Empalme del ARN , Receptores Androgénicos/genética , Transducción de Señal/efectos de los fármacos , Activación Transcripcional , Ensayos Antitumor por Modelo de Xenoinjerto
9.
J Endod ; 42(5): 711-6, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26975415

RESUMEN

INTRODUCTION: CD44 is a cell-surface glycoprotein involved in various cellular functions. Recent studies have suggested that CD44 is involved in early mineralization of odontoblasts. Hyaluronic acid (HA) is the principal ligand for receptor CD44. Whether and how HA regulated the mineralization process of dental pulp cells were investigated. METHODS: The effects of high-molecular-weight HA on differentiation and mineral deposition of dental pulp cells were tested by using alkaline phosphatase (ALP) activity assay and alizarin red S staining. Osteogenesis real-time polymerase chain reaction array, quantitative polymerase chain reaction, and Western blotting were performed to identify downstream molecules involved in the mineralization induction of HA. CD44 was knocked down and examined to confirm whether the mineralization effect of HA was mediated by receptor CD44. Immunohistochemistry was used to understand the localization patterns of CD44 and the identified downstream proteins in vivo. RESULTS: Pulse treatment of HA enhanced ALP activity and mineral deposition in dental pulp cells. Tissue-nonspecific ALP, bone morphogenetic protein 7 (BMP7), and type XV collagen (Col15A1) were upregulated via the HA-CD44 pathway in vitro. Immunohistochemistry of tooth sections showed that the staining pattern of BMP7 was very similar to that of CD44. CONCLUSIONS: Results of this study indicated that high-molecular-weight HA enhanced early mineralization of dental pulp cells mediated via CD44. The process involved important mineralization-associated molecules including tissue-nonspecific ALP, BMP7, and Col15A1. The findings may help develop new strategies in regenerative endodontics.


Asunto(s)
Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Pulpa Dental/metabolismo , Receptores de Hialuranos/farmacología , Ácido Hialurónico/farmacología , Calcificación de Dientes/efectos de los fármacos , Adulto , Fosfatasa Alcalina/efectos de los fármacos , Fosfatasa Alcalina/metabolismo , Antraquinonas , Western Blotting , Proteína Morfogenética Ósea 7/efectos de los fármacos , Proteína Morfogenética Ósea 7/metabolismo , Calcificación Fisiológica/efectos de los fármacos , Técnicas de Cultivo de Célula , Diferenciación Celular/efectos de los fármacos , Colágeno/efectos de los fármacos , Colágeno/metabolismo , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/administración & dosificación , Sialoproteína de Unión a Integrina/efectos de los fármacos , Sialoproteína de Unión a Integrina/metabolismo , Metaloproteinasa 13 de la Matriz/efectos de los fármacos , Metaloproteinasa 13 de la Matriz/metabolismo , Tercer Molar/citología , Odontoblastos/efectos de los fármacos , Osteogénesis , Reacción en Cadena en Tiempo Real de la Polimerasa , Regulación hacia Arriba
10.
Biomedicine (Taipei) ; 5(3): 15, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26264479

RESUMEN

(-)-Epigallocatechin-3-gallate (EGCG) is the most abundant catechin with various biological activities found in tea. In this study, the effects of EGCG on the metabolism and toxicity of acetaminophen in rat liver were investigated. Male Sprague-Dawley rats were fed a controlled diet without or with EGCG (0.54 %, w/w) for 1 week and were then intraperitoneally injected with acetaminophen (1 g/kg body weight) and killed after 12 h. Concentrations of acetaminophen and its conjugates in plasma and liver were then determined. The cytochrome P450 (CYP) and phase II enzymes activities were also evaluated. Rats fed the EGCG diet had lower plasma alanine aminotransferase and aspartate aminotransferase activities, as indices of hepatotoxicity, after acetaminophen treatment. Morphological damage by acetaminophen was lower in rats fed the EGCG diet. In addition, EGCG significantly reduced hepatic activities of midazolam 1-hydroxylation (CYP3A), nitrophenol 6-hydroxylase (CYP2E1), UDP-glucurosyltransferase, and sulfotransferase. Finally, EGCG feeding reduced acetaminophen-glucuronate and acetaminophen-glutathione contents in plasma and liver. These results indicate that EGCG feeding may reduce the metabolism and toxicity of acetaminophen in rats.

11.
BMC Biotechnol ; 15: 23, 2015 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-25880121

RESUMEN

BACKGROUND: Helicobacter pylori neutrophil-activating protein (HP-NAP) is involved in H. pylori-induced gastric inflammation. Due to its immunogenic and immunomodulatory properties, HP-NAP has been used for developing vaccines against H. pylori infection and new drugs for cancer therapy. RESULTS: Here, we provide a simple process for high-yield production of HP-NAP by applying one-step negative chromatography to purify recombinant HP-NAP expressed in Escherichia coli (E. coli). In our E. coli expression system, recombinant HP-NAP constitutes nearly 70% of the total protein. Overexpressed recombinant HP-NAP is almost completely soluble upon cell lysis at pH 9.5. Under the optimal condition at pH 8.0, recombinant HP-NAP with purity higher than 95% can be obtained from E. coli by collecting the unbound fraction using diethylaminoethyl (DEAE) Sephadex resin in batch mode. The overall yield of HP-NAP from a 50-ml E. coli culture is ~19 mg. The purified HP-NAP folds into a multimer with a secondary structure of α-helix and is able to trigger the production of reactive oxygen species by neutrophils. CONCLUSIONS: Purification of recombinant HP-NAP overexpressed in E. coli using DEAE Sephadex negative mode batch chromatography is an efficient method for high-yield production of highly pure HP-NAP in its native state. The purified HP-NAP is useful for various clinical applications including vaccine development, diagnosis, and new drug development.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Helicobacter pylori/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Cromatografía , Helicobacter pylori/química , Concentración de Iones de Hidrógeno , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Solubilidad
12.
PLoS One ; 9(9): e107991, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25268119

RESUMEN

Androgen ablation therapy causes a temporary reduction in tumor burden in patients with advanced prostate cancer. Unfortunately the malignancy will return to form lethal castration-recurrent prostate cancer (CRPC). The androgen receptor (AR) remains transcriptionally active in CRPC in spite of castrate levels of androgens in the blood. AR transcriptional activity resides in its N-terminal domain (NTD). Possible mechanisms of continued AR transcriptional activity may include, at least in part, expression of constitutively active splice variants of AR that lack the C-terminal ligand-binding domain (LBD). Current therapies that target the AR LBD, would not be effective against these AR variants. Currently no drugs are clinically available that target the AR NTD which should be effective against these AR variants as well as full-length AR. Niphatenones were originally isolated and identified in active extracts from Niphates digitalis marine sponge. Here we begin to characterize the mechanism of niphatenones in blocking AR transcriptional activity. Both enantiomers had similar IC50 values of 6 µM for inhibiting the full-length AR in a functional transcriptional assay. However, (S)-niphatenone had significantly better activity against the AR NTD compared to (R)-niphatenone. Consistent with niphatenones binding to and inhibiting transactivation of AR NTD, niphatenones inhibited AR splice variant. Niphatenone did not affect the transcriptional activity of the related progesterone receptor, but slightly decreased glucocorticoid receptor (GR) activity and covalently bound to GR activation function-1 (AF-1) region. Niphatenone blocked N/C interactions of AR without altering either AR protein levels or its intracellular localization in response to androgen. Alkylation with glutathione suggests that niphatenones are not a feasible scaffold for further drug development.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Antineoplásicos Hormonales/farmacología , Éteres de Glicerilo/farmacología , Línea Celular Tumoral , Humanos , Concentración 50 Inhibidora , Masculino , Metribolona/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Estructura Terciaria de Proteína , Receptores Androgénicos/química , Receptores Androgénicos/fisiología , Estereoisomerismo , Activación Transcripcional/efectos de los fármacos
13.
Res Dev Disabil ; 35(8): 1878-84, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24802054

RESUMEN

Poor writing is common in children with Attention Deficit Hyperactivity Disorder (ADHD). However, the writing performance of children with ADHD has been rarely formally explored in Taiwan, so the purpose of this study was to investigate writing features of children with ADHD in Taiwan. There were 25 children with ADHD and 25 normal children involved in a standardization writing assessment - Written Language Test for Children, to assess their performance at the dictation, sentence combination, adding/deducting redical, cloze and sentence making subtests. The results showed that except for the score of the sentence combining subtest, the score of children with ADHD was lower than the normal student in the rest of the subtests. Almost 60% of ADHD children's scores were below the 25th percentile numbers, but only 20% for normal children. Thus, writing problems were common for children with ADHD in Taiwan, too. First, children with ADHD performed worse than normal children on the dictation and cloze subtests, showing the weaker abilities of retrieving correct characters from their mental lexicon. Second, children with ADHD performed worse on the adding/deducting redical subtest than normal children did. Finally, at the language level, the score of children with ADHD on the sentence combination subtest was not lower than normal children, implicating their normal grammatic competence. It is worth mentioning that Taiwanese children with ADHD ignore the details of characters when they are writing, a finding that is common across languages.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Escritura Manual , Lectura , Semántica , Escritura , Grupo de Ascendencia Continental Asiática/psicología , Trastorno por Déficit de Atención con Hiperactividad/rehabilitación , Niño , Femenino , Humanos , Conducta Impulsiva , Trastornos del Desarrollo del Lenguaje/psicología , Trastornos del Desarrollo del Lenguaje/rehabilitación , Masculino , Motivación , Desempeño Psicomotor , Taiwán , Escalas de Wechsler
14.
J Clin Invest ; 123(7): 2948-60, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23722902

RESUMEN

Hormone therapies for advanced prostate cancer target the androgen receptor (AR) ligand-binding domain (LBD), but these ultimately fail and the disease progresses to lethal castration-resistant prostate cancer (CRPC). The mechanisms that drive CRPC are incompletely understood, but may involve constitutively active AR splice variants that lack the LBD. The AR N-terminal domain (NTD) is essential for AR activity, but targeting this domain with small-molecule inhibitors is complicated by its intrinsic disorder. Here we investigated EPI-001, a small-molecule antagonist of AR NTD that inhibits protein-protein interactions necessary for AR transcriptional activity. We found that EPI analogs covalently bound the NTD to block transcriptional activity of AR and its splice variants and reduced the growth of CRPC xenografts. These findings suggest that the development of small-molecule inhibitors that bind covalently to intrinsically disordered proteins is a promising strategy for development of specific and effective anticancer agents.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Antineoplásicos Hormonales/farmacología , Compuestos de Bencidrilo/farmacología , Clorhidrinas/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/química , Animales , Antineoplásicos Hormonales/química , Compuestos de Bencidrilo/química , Células COS , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Clorhidrinas/química , Química Clic , Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes Reporteros , Humanos , Luciferasas/biosíntesis , Luciferasas/genética , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Orquiectomía , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Unión Proteica , Estructura Terciaria de Proteína , Receptores Androgénicos/química , Receptores Androgénicos/genética , Estereoisomerismo , Activación Transcripcional/efectos de los fármacos , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
15.
PLoS One ; 8(4): e60786, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23577158

RESUMEN

Helicobacter pylori neutrophil-activating protein (HP-NAP), a major virulence factor of Helicobacter pylori (H. pylori), is capable of activating human neutrophils to produce reactive oxygen species (ROS) and secrete inammatory mediators. HP-NAP is a vaccine candidate, a possible drug target, and a potential in vitro diagnostic marker for H. pylori infection. HP-NAP has also been shown to be a novel therapeutic agent for the treatment of allergic asthma and bladder cancer. Hence, an efficient way to obtain pure HP-NAP needs to be developed. In this study, one-step anion-exchange chromatography in negative mode was applied to purify the recombinant HP-NAP expressed in Bacillus subtilis (B. subtilis). This purification technique was based on the binding of host cell proteins and/or impurities other than HP-NAP to DEAE Sephadex resins. At pH 8.0, almost no other proteins except HP-NAP passed through the DEAE Sephadex column. More than 60% of the total HP-NAP with purity higher than 91% was recovered in the flow-through fraction from this single-step DEAE Sephadex chromatography. The purified recombinant HP-NAP was further demonstrated to be a multimeric protein with a secondary structure of α-helix and capable of activating human neutrophils to stimulate ROS production. Thus, this one-step negative chromatography using DEAE Sephadex resin can efficiently yield functional HP-NAP from B. subtilis in its native form with high purity. HP-NAP purified by this method could be further utilized for the development of new drugs, vaccines, and diagnostics for H. pylori infection.


Asunto(s)
Bacillus subtilis/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Cromatografía por Intercambio Iónico/métodos , Proteínas Bacterianas/química , Proteínas Bacterianas/farmacología , Expresión Génica , Humanos , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/farmacología
16.
Mol Cancer Ther ; 12(5): 621-31, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23443807

RESUMEN

Androgen receptor is a ligand-activated transcription factor and a validated drug target for all stages of prostate cancer. Antiandrogens compete with physiologic ligands for androgen receptor ligand-binding domain (LBD). High-throughput screening of a marine natural product library for small molecules that inhibit androgen receptor transcriptional activity yielded the furanoditerpenoid spongia-13(16),-14-dien-19-oic acid, designated terpene 1 (T1). Characterization of T1 and the structurally related semisynthetic analogues (T2 and T3) revealed that these diterpenoids have antiandrogen properties that include inhibition of both androgen-dependent proliferation and androgen receptor transcriptional activity by a mechanism that involved competing with androgen for androgen receptor LBD and blocking essential N/C interactions required for androgen-induced androgen receptor transcriptional activity. Structure-activity relationship analyses revealed some chemical features of T1 that are associated with activity and yielded T3 as the most potent analogue. In vivo, T3 significantly reduced the weight of seminal vesicles, which are an androgen-dependent tissue, thereby confirming the on-target activity of T3. The ability to create analogues of diterpenoids that have varying antiandrogen activity represents a novel class of chemical compounds for the analysis of androgen receptor ligand-binding properties and therapeutic development.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Diterpenos/farmacología , Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/química , Andrógenos/metabolismo , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diterpenos/química , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Receptores Androgénicos/química , Transcripción Genética
17.
Cancer Lett ; 307(2): 191-9, 2011 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-21536374

RESUMEN

Overexpression of Id family proteins inhibits cell differentiation and enhances cell proliferation and invasiveness. Although Id1 is the Id family member mostly linked to tumorigenesis, its role in lung cancer is unclear. An elevated Id1 expression was observed in lung cancer cell lines as well as lung cancer tissues. Id1 overexpression increased cell proliferation while Id1 knockdown decreased cell proliferation, mostly through Akt-related pathway. Nude mice study further confirmed an increased tumor growth in Id1-overexpressing cells and a decreased tumor growth in Id1-knockdowned cells. In conclusion, inactivation of Id1 may provide a novel strategy for treatment of lung cancer patients.


Asunto(s)
Proliferación Celular , Proteína 1 Inhibidora de la Diferenciación/fisiología , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Secuencia de Bases , Línea Celular Tumoral , Cartilla de ADN , Técnicas de Silenciamiento del Gen , Humanos , Proteína 1 Inhibidora de la Diferenciación/genética , Neoplasias Pulmonares/enzimología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos
18.
Cancer Cell ; 17(6): 535-46, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20541699

RESUMEN

Castration-recurrent prostate cancer (CRPC) is suspected to depend on androgen receptor (AR). The AF-1 region in the amino-terminal domain (NTD) of AR contains most, if not all, of the transcriptional activity. Here we identify EPI-001, a small molecule that blocked transactivation of the NTD and was specific for inhibition of AR without attenuating transcriptional activities of related steroid receptors. EPI-001 interacted with the AF-1 region, inhibited protein-protein interactions with AR, and reduced AR interaction with androgen-response elements on target genes. Importantly, EPI-001 blocked androgen-induced proliferation and caused cytoreduction of CRPC in xenografts dependent on AR for growth and survival without causing toxicity.


Asunto(s)
Antagonistas de Receptores Androgénicos , Antineoplásicos Hormonales/uso terapéutico , Compuestos de Bencidrilo/uso terapéutico , Castración , Clorhidrinas/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Andrógenos/farmacología , Animales , Antineoplásicos Hormonales/efectos adversos , Antineoplásicos Hormonales/farmacología , Apoptosis/efectos de los fármacos , Compuestos de Bencidrilo/efectos adversos , Compuestos de Bencidrilo/farmacología , Proteína de Unión a CREB/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Clorhidrinas/efectos adversos , Clorhidrinas/farmacología , ADN/genética , ADN/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Ligandos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Estructura Molecular , Recurrencia Local de Neoplasia/patología , Próstata/anatomía & histología , Próstata/efectos de los fármacos , Próstata/patología , Antígeno Prostático Específico/sangre , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Unión Proteica/efectos de los fármacos , Unión Proteica/genética , Conformación Proteica/efectos de los fármacos , Dominios y Motivos de Interacción de Proteínas/efectos de los fármacos , Multimerización de Proteína/efectos de los fármacos , Receptores Androgénicos/metabolismo , Receptores de Esteroides/efectos de los fármacos , Elementos de Respuesta/genética , Serina Endopeptidasas/genética , Activación Transcripcional/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
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