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1.
Molecules ; 26(1)2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33406699

RESUMEN

Conventional chemotherapies used for breast cancer (BC) treatment are non-selective, attacking both healthy and cancerous cells. Therefore, new technologies that enhance drug efficacy and ameliorate the off-target toxic effects exhibited by currently used anticancer drugs are urgently needed. Here we report the design and synthesis of novel mesoporous silica nanoparticles (MSNs) equipped with the hormonal drug tamoxifen (TAM) to facilitate guidance towards estrogen receptors (ERs) which are upregulated in breast tumours. TAM is linked to the MSNs using a poly-ʟ-histidine (PLH) polymer as a pH-sensitive gatekeeper, to ensure efficient delivery of encapsulated materials within the pores. XRD, HR-TEM, DLS, SEM, FT-IR and BET techniques were used to confirm the successful fabrication of MSNs. The MSNs have a high surface area (>1000 m2/g); and a mean particle size of 150 nm, which is an appropriate size to allow the penetration of premature blood vessels surrounding breast tumours. Successful surface functionalization was supported by FT-IR, XPS and TGA techniques, with a grafting ratio of approximately 29%. The outcomes of this preliminary work could be used as practical building blocks towards future formulations.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Dióxido de Silicio/química , Tamoxifeno/farmacología , Antineoplásicos Hormonales/química , Composición de Medicamentos , Diseño de Fármacos , Descubrimiento de Drogas , Liberación de Fármacos , Femenino , Humanos , Nanopartículas/química , Porosidad , Tamoxifeno/química
2.
Pharm Res ; 37(10): 193, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32914377

RESUMEN

PURPOSE: The incidence of breast cancer worldwide has been on the rise since the late 1970s, and it has become a common tumor that threatens women's health. Aminoglutethimide (AG) is a common treatment of breast cancer. However, current treatments require frequent dosing that results in unstable plasma concentration and low bioavailability, risking serious adverse reactions. Our goal was to develop a molecularly imprinted polymer (MIP) based delivery system to control the release of AG and demonstrate the availability of this drug delivery system (DDS), which was doped with carbon nanotube with aid of metal-organic gel. METHODS: Preparation of MIP was optimized by key factors including composition of formula, ratio of monomers and drug loading concentration. RESULTS: By using multi-walled carbon nanotubes (MWCNT) and metal-organic gels (MOGs), MIP doubled the specific surface area, pore volume tripled and the IF was 1.6 times than the reference. Compared with commercial tablets, the relative bioavailability was 143.3% and a more stable release appeared. CONCLUSIONS: The results highlight the influence of MWCNT and MOGs on MIP, which has great potential as a DDS.


Asunto(s)
Aminoglutetimida/química , Antineoplásicos Hormonales/química , Complejos de Coordinación/química , Sistemas de Liberación de Medicamentos/métodos , Nanotubos de Carbono/química , Aminoglutetimida/administración & dosificación , Aminoglutetimida/farmacocinética , Animales , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/farmacocinética , Complejos de Coordinación/administración & dosificación , Compuestos Férricos/química , Geles/administración & dosificación , Geles/química , Humanos , Células MCF-7 , Masculino , Impresión Molecular/métodos , Ratas , Ácidos Tricarboxílicos/química
3.
Breast Cancer Res ; 22(1): 80, 2020 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-32727562

RESUMEN

BACKGROUND: The estrogen receptor (ER)-positive breast cancer represents over 80% of all breast cancer cases. Even though adjuvant hormone therapy with tamoxifen (TMX) is saving lives of patients with ER-positive breast cancer, the acquired resistance to TMX anti-estrogen therapy is the main hurdle for successful TMX therapy. Here we address the mechanism for TMX resistance and explore the ways to eradicate TMX-resistant breast cancer in both in vitro and ex vivo experiments. EXPERIMENTAL DESIGN: To identify compounds able to overcome TMX resistance, we used short-term and long-term viability assays in cancer cells in vitro and in patient samples in 3D ex vivo, analysis of gene expression profiles and cell line pharmacology database, shRNA screen, CRISPR-Cas9 genome editing, real-time PCR, immunofluorescent analysis, western blot, measurement of oxidative stress using flow cytometry, and thioredoxin reductase 1 enzymatic activity. RESULTS: Here, for the first time, we provide an ample evidence that a high level of the detoxifying enzyme SULT1A1 confers resistance to TMX therapy in both in vitro and ex vivo models and correlates with TMX resistance in metastatic samples in relapsed patients. Based on the data from different approaches, we identified three anticancer compounds, RITA (Reactivation of p53 and Induction of Tumor cell Apoptosis), aminoflavone (AF), and oncrasin-1 (ONC-1), whose tumor cell inhibition activity is dependent on SULT1A1. We discovered thioredoxin reductase 1 (TrxR1, encoded by TXNRD1) as a target of bio-activated RITA, AF, and ONC-1. SULT1A1 depletion prevented the inhibition of TrxR1, induction of oxidative stress, DNA damage signaling, and apoptosis triggered by the compounds. Notably, RITA efficiently suppressed TMX-unresponsive patient-derived breast cancer cells ex vivo. CONCLUSION: We have identified a mechanism of resistance to TMX via hyperactivated SULT1A1, which renders selective vulnerability to anticancer compounds RITA, AF, and ONC-1, and provide a rationale for a new combination therapy to overcome TMX resistance in breast cancer patients. Our novel findings may provide a strategy to circumvent TMX resistance and suggest that this approach could be developed further for the benefit of relapsed breast cancer patients.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/farmacología , Tamoxifeno/farmacología , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacología , Apoptosis , Arilsulfotransferasa/genética , Arilsulfotransferasa/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Femenino , Humanos , Tamoxifeno/química , Células Tumorales Cultivadas
4.
Talanta ; 208: 120286, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31816809

RESUMEN

Tumor markers play an important role in the early diagnosis and therapeutic effect monitoring of tumors. An electrochemical biosensor was developed based on multi-branched gold nanoshells (BGSs) and octreotide (OCT) functionalized Pt nano-flakes (PtNFs) modified electrodes, which was used for detection of tumor-specific markers to evaluate tumor cells. Sandwich-type nano-hybrid materials were prepared by layer-by-layer modification. First, reduced graphene oxide (RGO) and BGSs were modified as electronic materials onto glassy carbon electrodes (GCE). This modified electrode has strong electron transfer capability and large electrode surface area. The OCT was then anchored to the surface of BGSs to sensitively detect Somatostatin receptors (SSTRs) on the surface of HeLa cells. In addition, PtNFs were synthesized using a dual-template method, and OCT template on the surface of PtNFs, as an adsorption bioprobe, was used to reduce the H2O2 and amplify the electrochemical signal of biosensor. The proposed biosensor can be applied to the quantitative broad linear range of HeLa cells covering from 10 to 1 × 106 cells mL-1 (R2 = 0.9998) and the limit of detection (LOD) was 2 cells mL-1. The experimental results also show that the sensor has good stability, biocompatibility and high selectivity, which has great potential for clinical application.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Nanopartículas del Metal/química , Octreótido/administración & dosificación , Platino (Metal)/química , Receptores de Somatostatina/metabolismo , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/química , Electrodos , Oro/química , Células HeLa , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología , Octreótido/química
5.
Biomed Chromatogr ; 34(3): e4776, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31826297

RESUMEN

Mitotane is a key drug for the treatment of adrenal cortical carcinoma. Due to its narrow therapeutic window, 14-20 µg/mL, monitoring its concentration is crucially important. In this study, a simplified method for measuring mitotane in plasma using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) was developed. Through deproteination and liquid-liquid extraction, mitotane and an internal standard (IS) were extracted from plasma samples. GC-EI-MS yielded retention times of 8.2 and 8.7 min, for mitotane and the IS, respectively, with a total run time of 12 min. Selectivity and intra-/inter-batch accuracy and precision analyses provided a lower limit of quantification of 0.25 µg/mL, and a calibration curve between 0.25 and 40 µg/mL had good linearity (coefficient of determination = 0.992). The matrix effect factor and percent recovery of the method had good precision. Additionally, long-term sample stability was observed below 4°C. In a clinical setting, mitotane levels in plasma from an adrenal cortical carcinoma patient were within calibration range. Therefore, this simplified method can be applied to routine therapeutic drug monitoring of mitotane, which may contribute to improved treatment of adrenal cortical carcinoma.


Asunto(s)
Antineoplásicos Hormonales/sangre , Monitoreo de Drogas/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Mitotano/sangre , Neoplasias de la Corteza Suprarrenal/tratamiento farmacológico , Carcinoma Corticosuprarrenal/tratamiento farmacológico , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacocinética , Antineoplásicos Hormonales/uso terapéutico , Humanos , Límite de Detección , Modelos Lineales , Mitotano/química , Mitotano/farmacocinética , Mitotano/uso terapéutico , Reproducibilidad de los Resultados
6.
Colloids Surf B Biointerfaces ; 184: 110549, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31610417

RESUMEN

Designing biomimetic scaffolds is an intellectual challenge of the realm of regenerative medicine and tissue engineering. An electroactive substrate should meet multidisciplinary mimicking the mechanical, electrical, and electrochemical properties of neural tissues. Hydrogels have been known platforms to regulate neural interface modulus, but the lack of conductivity always hampered their applications; hence, developing conductive hydrogels with on-demand drug release has become a concern of tissue engineering. In this work, electroactive hydrogels based on chitosan-aniline oligomer and agarose with self-gelling properties were synthesized, and their electrical, thermal, and electrochemical properties were characterized by Fourier transform infrared (FTIR), cyclic voltammetry (CV), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA), and four probe method . The conductivity of the as-prepared aniline oligomer-based hydrogel was ∼10-4 S/cm; which fell within the range of conductivities appropriate for applications in tissue engineering. The aniline oligomer played a key role in controlling the hydrogel properties by regulating the glass transition temperature and thermal properties. In addition, the swelling and degradation rates were decreased because of the hydrophobic properties of the aniline oligomer. The swelling capacity of the pristine hydrogel was ∼800%, while that of the conductive hydrogel decreased to ∼300%. The conductivity of the hydrogel was regulated by modifying the macromolecular architecture through aniline oligomer incorporation thanks to its conductivity on-demand drug release was observed by electrical stimulation, in which a large amount of the drug was released by voltage application. Biocompatibility analysis of the designed hydrogel was indicative of the conductivity enhancement, as reflected in the growth and proliferation of cellular activity.


Asunto(s)
Compuestos de Anilina/química , Antineoplásicos Hormonales/química , Quitosano/química , Dexametasona/química , Hidrogeles/química , Sefarosa/química , Ingeniería de Tejidos , Animales , Antineoplásicos Hormonales/farmacología , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dexametasona/farmacología , Liberación de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Conductividad Eléctrica , Técnicas Electroquímicas , Hidrogeles/síntesis química , Hidrogeles/farmacología , Estructura Molecular , Células PC12 , Tamaño de la Partícula , Ratas , Propiedades de Superficie , Células Tumorales Cultivadas
7.
J Pharm Pharmacol ; 71(12): 1839-1853, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31588558

RESUMEN

OBJECTIVES: To study anticancer effects, underlying mechanism and safety of ethoxy mansonone G (EMG) which is the potent derivative of mansonone G (MG) in breast cancer cells. METHODS: Anticancer, antimigration, anti-invasion effects and anchorage-independent growth were investigated by MTT, scratch, matrigel invasion and soft agar assays. Estrogen receptor (ER)-targeted genes and endocrine-resistant genes were assessed by RT-PCR and Western blot. KEY FINDINGS: Ethoxy mansonone G is the most potent MG derivative and has anticancer effects in ER-positive, endocrine-resistant and ER-negative breast cancer cells. Our results demonstrated that EMG can significantly inhibit estrogen-induced cell proliferation and the expression of ER-targeted genes in ER-positive breast cancer cells, suggesting the anti-estrogenic property of EMG which is consisting with the virtual molecular docking that EMG could possibly bind to the ERα. Moreover, EMG has synergistic effect with tamoxifen in endocrine-resistant cells. EMG also inhibited cell proliferation, invasion and anchorage-independent growth by reducing expression of genes involved in endocrine resistance and invasive factors during the metastatic process. CONCLUSION: Ethoxy mansonone G has an anticancer effect in breast cancer cells and is possible to use as a therapeutic agent in patients with breast cancer.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Naftoquinonas/administración & dosificación , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/química , Neoplasias de la Mama/patología , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Receptor alfa de Estrógeno/metabolismo , Éteres de Etila/administración & dosificación , Éteres de Etila/química , Éteres de Etila/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Células MCF-7 , Simulación del Acoplamiento Molecular , Naftoquinonas/química , Naftoquinonas/farmacología , Receptores Estrogénicos/metabolismo , Tamoxifeno/administración & dosificación , Tamoxifeno/farmacología
8.
Org Biomol Chem ; 17(19): 4892-4905, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-31041982

RESUMEN

A series of 2,3,4-triaryl-substituted 1,2,4-oxadiazole-5-ones have been prepared as fixed-ring analogues of tamoxifen (TAM), a drug inhibitor of Estradiol Receptor (ER) used in breast cancer therapy, by an efficient synthetic protocol based on a 1,3-dipolar cycloaddition of nitrones to isocyanates. Some of the newly synthesized compounds (14d-f, 14h and 14k) show a significant cytotoxic effect in a human breast cancer cell line (MCF-7) possessing IC50 values between 15.63 and 31.82 µM. In addition, compounds 14d-f, 14h and 14k are able to increase the p53 expression levels, activating also the apoptotic pathway. Molecular modeling studies of novel compounds performed on the crystal structure of ER reveal the presence of strong hydrophobic interactions with the aromatic rings of the ligands similar to TAM. These data suggest that 1,2,4-oxadiazole-5-ones can be considered analogues of TAM, and that their anticancer activity might be partially due to ER inhibition.


Asunto(s)
Antineoplásicos Hormonales/síntesis química , Antineoplásicos Hormonales/farmacología , Oxadiazoles/síntesis química , Oxadiazoles/farmacología , Tamoxifeno/análogos & derivados , Antineoplásicos Hormonales/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 , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Células MCF-7 , Estructura Molecular , Oxadiazoles/química , Teoría Cuántica , Relación Estructura-Actividad , Tamoxifeno/química , Células Tumorales Cultivadas
9.
Int J Pharm ; 560: 273-281, 2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-30731258

RESUMEN

Studies have shown that the N-terminus and lysine side residue of peptides are prone to acylation in poly(d,l-lactide-co-glycolide) (PLGA) microspheres. Peptides such as leuprorelin lack a free N-terminus or lysine and only contain serine, arginine, and tyrosine as nucleophilic residues. The purpose of this study was to detect potential acylation impurities and determine their corresponding acylation sites in commercial leuprorelin-loaded PLGA microspheres. Commercial samples from three vendors were selected as targets for our study. The high-performance liquid chromatography (HPLC) conditions of the European Pharmacopoeia were used to separate and collect impurities. HPLC-tandem mass spectrometry (HPLC-MS/MS) was applied to confirm both the structure and acylation sites of the impurities. Our study demonstrated that impurities originating from both degradation of microspheres and synthesis of leuprorelin were well separated and identified using these HPLC conditions. HPLC-MS/MS analysis of acylated leuprorelin showed that diglycoyl, lactoyl-glycoyl, dilactoyl, and monolactoyl groups were conjugated to serine in leuprorelin-loaded PLGA microspheres. This is the first report showing serine to be the acylation site in peptide-loaded PLGA microspheres. Separation and identification of acylated leuprorelin derivatives will assist in minimising acylation and guiding the development of quality control for commercial leuprorelin-loaded PLGA microspheres.


Asunto(s)
Química Farmacéutica/métodos , Portadores de Fármacos/química , Leuprolida/administración & dosificación , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Acilación , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/normas , Cromatografía Líquida de Alta Presión/métodos , Contaminación de Medicamentos/prevención & control , Leuprolida/química , Leuprolida/normas , Microesferas , Control de Calidad , Espectrometría de Masas en Tándem/métodos
10.
Molecules ; 24(3)2019 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-30678347

RESUMEN

A series of estrone derivatives 3⁻8 was designed and synthesized using estrone arylmethylenes 2a,b as starting materials and their structures were confirmed by different spectral data and elemental analyses. All the newly synthesized compounds exhibited potent in vitro and in vivo cytotoxic activities against breast cancer cell lines. In addition, all compounds were subjected to in vitro and in vivo inhibition assays for EGFR and VEGFR-2 kinases as well as p53 ubiquitination activity to obtain more details about their mechanism of action. Based on the promising results, a molecular docking study was investigated for the most representative compound 5a against the two targets, EGFR and VEGFR-2 kinases, to assess its binding affinity, hoping to rationalize and obtain potent anticancer agents in the future.


Asunto(s)
Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacología , Diseño de Fármacos , Estrógenos/química , Estrógenos/farmacología , Modelos Moleculares , Animales , Antineoplásicos Hormonales/síntesis química , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Técnicas de Química Sintética , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Estrógenos/análogos & derivados , Estrógenos/síntesis química , Femenino , Humanos , Concentración 50 Inhibidora , Ratones , Estructura Molecular , Unión Proteica , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Relación Estructura-Actividad Cuantitativa , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitinación/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Arch Pharm (Weinheim) ; 352(3): e1800295, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30600539

RESUMEN

Nomegestrol acetate (NOMAc) is a synthetic progesterone analog and classified as a fourth-generation progestin. It has been approved in many countries for oral contraception, hormonal replacement therapy (HRT), and treatment of various gynecological disorders. There are several synthetic routes reported for the synthesis of NOMAc and they all share the very similar last three to five steps toward the conversion of 6-methylene to 6-methyl-6,7-unsaturated structure. Therefore the final product from different processing routes may have similar impurity profiles. In the analysis of NOMAc, we identified two impurities, impurity A (listed in EP 8.0) and impurity B (not specified in EP 8.0). Both impurities were further confirmed by synthesis. In addition, both impurities and NOMAc were evaluated for their in vitro cytotoxicities against L02 liver cells, mesenchymal stem cells, MCF-7 breast cancer cells, and C33A cervical cancer cells. These three analogs are not cytotoxic to the four cell lines at low concentrations (<20 µM). NOMAc and impurity A showed cytotoxicity to L02, MCF-7, and C33A cells at high concentrations, while impurity B did not show significant cytotoxicity to any of the cell lines tested.


Asunto(s)
Antineoplásicos Hormonales/síntesis química , Descubrimiento de Drogas/métodos , Megestrol/síntesis química , Norpregnadienos/síntesis química , Congéneres de la Progesterona/síntesis química , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Contaminación de Medicamentos , Humanos , Megestrol/química , Megestrol/farmacología , Estructura Molecular , Norpregnadienos/química , Norpregnadienos/farmacología , Congéneres de la Progesterona/química , Congéneres de la Progesterona/farmacología
12.
J Mol Graph Model ; 87: 240-249, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30594032

RESUMEN

The present study is aimed to analyze lipophilicity and ADMET profiles, and to develop field based 3D-QSAR and ligand-based pharmacophore hypothesis for a series of 17α-picolyl and 17(E)-picolinylidene androstane derivatives in order to give detailed structural insights and to highlight important binding features of novel androstane derivatives, as compounds with antiproliferative activity toward breast adenocarcinoma cells. This study can provide guidelines for the rational design of novel potent compounds. Sum of ranking differences (SRD), as a non-parametric method, was applied for compounds ranking. 3D-QSAR methods, including comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA), were applied to predict the antiproliferative effect on breast adenocarcinoma cells and provide the regions in space where interactive fields may influence the activity. The compounds are ranked so the compounds with the most favorable ADME and lipophilicity features together with significant anticancer activity can be distinguished. The established 3D-QSAR model could be used for design of new compounds with antiproliferative activity on the human ER- breast adenocarcinoma cells. The pharmacophore model is able to accurately predict antiproliferative activity. Generally, the present study provides significant guidelines for further selection, synthesis and rational design of new highly potential androstane derivatives as anticancer drugs.


Asunto(s)
Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacología , Relación Estructura-Actividad Cuantitativa , Esteroides/química , Esteroides/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Modelos Moleculares , Relación Estructura-Actividad
13.
Biomed Chromatogr ; 33(4): e4462, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30536934

RESUMEN

To date, several methods for the quantification of tamoxifen and its metabolites have been developed, most of which employ liquid chromatography tandem-mass spectrometry (LC-MS/MS). These methods are highly sensitive and reproducible, but are also time-consuming and require expensive equipment; one of their main disadvantages is matrix ionization effects. A more viable option, particularly in developing countries, is high-performance liquid chromatography coupled with UV or fluorescence detection. We developed and validated a method for simultaneous quantification of tamoxifen, endoxifen and 4-hydroxytamoxifen based on high-performance liquid chromatography with fluorescence detection in a reverse-phase column. The method is rapid (16 min plus 5 min of column re-equilibrium), accurate (80-100%) and precise (0.23-6.00%), and does not require any additional irradiation process. Sample pretreatment consists of protein precipitation with acetonitrile under alkaline conditions, employing only 200 µL plasma. The validated method's wide range allowed quantification of steady-state levels in patients under standard tamoxifen treatment (20 mg/day). This assay is ready for application in clinical studies and routine quantification of tamoxifen, endoxifen and 4-hydroxytamoxifen in healthcare institutions.


Asunto(s)
Antineoplásicos Hormonales/sangre , Neoplasias de la Mama/tratamiento farmacológico , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Fluorescencia/métodos , Tamoxifeno/sangre , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/uso terapéutico , Monitoreo de Drogas/métodos , Femenino , Humanos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Tamoxifeno/análogos & derivados , Tamoxifeno/química , Tamoxifeno/uso terapéutico
15.
J Biol Chem ; 294(2): 453-460, 2019 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-30425102

RESUMEN

Human cytochrome P450 11B1 (CYP11B1) is responsible for the final step generating the steroid hormone cortisol, which controls stress and immune responses and glucose homeostasis. CYP11B1 is a promising drug target to manage Cushing's disease, a disorder arising from excessive cortisol production. However, the design of selective inhibitors has been hampered because structural information for CYP11B1 is unavailable and the enzyme has high amino acid sequence identity (93%) to a closely related enzyme, the aldosterone-producing CYP11B2. Here we report the X-ray crystal structure of human CYP11B1 (at 2.1 Å resolution) in complex with fadrozole, a racemic compound normally used to treat breast cancer by inhibiting estrogen-producing CYP19A1. Comparison of fadrozole-bound CYP11B1 with fadrozole-bound CYP11B2 revealed that despite conservation of the active-site residues, the overall structures and active sites had structural rearrangements consistent with distinct protein functions and inhibition. Whereas fadrozole binds to both CYP11B enzymes by coordinating the heme iron, CYP11B2 binds to the R enantiomer of fadrozole, and CYP11B1 binds to the S enantiomer, each with distinct orientations and interactions. These results provide insights into the cross-reactivity of drugs across multiple steroidogenic cytochrome P450 enzymes, provide a structural basis for understanding human steroidogenesis, and pave the way for the design of more selective inhibitors of each human CYP11B enzyme.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Fadrozol/farmacología , Hidrocortisona/metabolismo , Esteroide 11-beta-Hidroxilasa/antagonistas & inhibidores , Esteroide 11-beta-Hidroxilasa/metabolismo , Antineoplásicos Hormonales/química , Neoplasias de la Mama/metabolismo , Dominio Catalítico/efectos de los fármacos , Cristalografía por Rayos X , Diseño de Fármacos , Fadrozol/química , Femenino , Humanos , Simulación del Acoplamiento Molecular , Conformación Proteica/efectos de los fármacos , Esteroide 11-beta-Hidroxilasa/química
16.
J Mol Cell Biol ; 11(8): 649-664, 2019 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-30383247

RESUMEN

Acquired drug resistance is the major reason why patients fail to respond to cancer therapies. It is a challenging task to determine the tipping point of endocrine resistance and detect the associated molecules. Derived from new systems biology theory, the dynamic network biomarker (DNB) method is designed to quantitatively identify the tipping point of a drastic system transition and can theoretically identify DNB genes that play key roles in acquiring drug resistance. We analyzed time-course mRNA sequence data generated from the tamoxifen-treated estrogen receptor (ER)-positive MCF-7 cell line, and identified the tipping point of endocrine resistance with its leading molecules. The results show that there is interplay between gene mutations and DNB genes, in which the accumulated mutations eventually affect the DNB genes that subsequently cause the change of transcriptional landscape, enabling full-blown drug resistance. Survival analyses based on clinical datasets validated that the DNB genes were associated with the poor survival of breast cancer patients. The results provided the detection for the pre-resistance state or early signs of endocrine resistance. Our predictive method may greatly benefit the scheduling of treatments for complex diseases in which patients are exposed to considerably different drugs and may become drug resistant.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Células MCF-7 , Mutación/genética , Biología de Sistemas , Tamoxifeno/química , Tamoxifeno/farmacología
17.
J Mol Model ; 24(12): 336, 2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30413890

RESUMEN

Here, we report theoretical research into the interaction of the drug tamoxifen drug with tripeptides found in the tumor environment-specifically, asparagine-glycine-arginine (NGR) and arginine-glycine-aspartic acid (RGD). Reactivity parameters of these tripeptides were calculated and their intrinsic reactivities and cross-reactivities were analyzed. The interactions of the tripeptides with the nanodiamond-tamoxifen (ND-TAM) complex where the nanodiamond acts as a nanocarrier were also examined theoretically. In addition, their intestinal absorption was predicted based on the polar surface area. The results showed that tamoxifen interacts with RGD, and this interaction remained after the addition of the nanodiamond. An analysis of the chemical hardnesses of the tripeptides was carried out to explore their possible use as synthetic vectors when joined to the nanodiamond. Results indicated that NGR is the most stable of the tripeptides and could be used for active targeting. All calculations were implemented using the conceptual framework of density functional theory.


Asunto(s)
Teoría Funcional de la Densidad , Oligopéptidos/química , Tamoxifeno/química , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/metabolismo , Antineoplásicos Hormonales/farmacocinética , Supervivencia Celular/efectos de los fármacos , Liberación de Fármacos/efectos de los fármacos , Humanos , Modelos Moleculares , Nanodiamantes/administración & dosificación , Nanodiamantes/química , Neoplasias/química , Neoplasias/metabolismo , Neoplasias/patología , Oligopéptidos/metabolismo , Oligopéptidos/farmacocinética , Unión Proteica/efectos de los fármacos , Tamoxifeno/metabolismo , Tamoxifeno/farmacocinética , Termodinámica , Microambiente Tumoral/efectos de los fármacos
18.
AAPS J ; 20(6): 105, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30280294

RESUMEN

The 1-month Lupron Depot® (LD) encapsulating water-soluble leuprolide in poly(lactic-co-glycolic acid) (PLGA) microspheres is a benchmark product upon which modern long-acting release products are often compared. Despite expiration of patent coverage, no generic product for the LD has been approved in the USA, likely due to the complexity of components and manufacturing processes involved in the product. Here, we describe the reverse engineering of the LD composition and important product attributes. Specific attributes analyzed for microspheres were as follows: leuprolide content by three methods; gelatin content, type, and molecular weight distribution; PLGA content, lactic acid/glycolic acid ratio, and molecular weight distribution; mannitol content; in vitro drug release; residual solvent and moisture content; particle size distribution and morphology; and glass transition temperature. For the diluent, composition, viscosity, and specific gravity were analyzed. Analyzed contents of the formulation and the determined PLGA characteristics matched well with the official numbers stated in the package insert and those found in literature, respectively. The gelatin was identified as type B consistent with ~ 300 bloom. The 11-µm volume-median microspheres in the LD slowly released the drug in vitro in a zero-order manner after ~ 23% initial burst release. Very low content of residual moisture (< 0.5%) and methylene chloride (< 1 ppm) in the product indicates in-water drying is capable of removing solvents to extremely low levels during manufacturing. The rigorous approach of reverse engineering described here may be useful for development of generic leuprolide-PLGA microspheres as well as other new and generic PLGA microsphere formulations.


Asunto(s)
Antineoplásicos Hormonales/química , Ingeniería Química/métodos , Química Farmacéutica/métodos , Portadores de Fármacos/química , Medicamentos Genéricos/química , Leuprolida/química , Antineoplásicos Hormonales/farmacocinética , Ingeniería Química/legislación & jurisprudencia , Química Farmacéutica/legislación & jurisprudencia , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Liberación de Fármacos , Medicamentos Genéricos/farmacocinética , Excipientes/química , Leuprolida/farmacocinética , Microesferas , Peso Molecular , Tamaño de la Partícula , Patentes como Asunto , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Viscosidad
19.
ACS Nano ; 12(10): 9866-9880, 2018 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-30189128

RESUMEN

Injectable hydrogels present several advantages over prefabricated scaffolds including ease of delivery, shear-thinning property, and broad applicability in the fields of drug delivery and tissue engineering. Here, we report an approach to develop injectable hydrogels with sustained drug release properties, exploiting the chemical nature of the DNA backbone and silicate nanodisks. A two-step gelation method is implemented for generating a combination of noncovalent network points, leading to a physically cross-linked hydrogel. The first step initiates the development of an interconnected structure by utilizing DNA denaturation and rehybridization mechanism to form hydrogen bonds between complementary base pairs of neighboring DNA strands. The anisotropic charge distribution of two-dimensional silicate nanodisks (nSi) makes them an active center in the second step of the gelation process. Silicate nanodisks create additional network points via attractive electrostatic interactions with the DNA backbone, thereby enhancing the mechanical resilience of the formulated hydrogel. The thermally stable hydrogels displayed an increase in elasticity and yield stress as a function of nSi concentration. They were able to form self-supporting structures post injection due to their rapid recovery after removal of cyclic stress. Moreover, the presence of nanosilicate was shown to modulate the release of a model osteogenic drug dexamethasone (Dex). The bioactivity of released Dex was confirmed from in vitro osteogenic differentiation of human adipose stem cells and in vivo bone formation in a rat cranial bone defect model. Overall, our DNA-based nanocomposite hydrogel obtained from a combination of noncovalent network points can serve as an injectable material for bone regeneration and carrier for sustained release of therapeutics.


Asunto(s)
Antineoplásicos Hormonales/farmacología , ADN/química , Dexametasona/farmacología , Hidrogeles/farmacología , Nanoestructuras/química , Silicatos/química , Tejido Adiposo/efectos de los fármacos , Animales , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/química , Regeneración Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Dexametasona/administración & dosificación , Dexametasona/química , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Hidrogeles/administración & dosificación , Hidrogeles/química , Inflamación/tratamiento farmacológico , Inflamación/patología , Osteogénesis/efectos de los fármacos , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Ratas , Ratas Sprague-Dawley , Reología , Propiedades de Superficie
20.
Clin Cancer Res ; 24(24): 6509-6522, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30185422

RESUMEN

PURPOSE: Testosterone suppression in prostate cancer is limited by serious side effects and resistance via restoration of androgen receptor (AR) functionality. ELK1 is required for AR-dependent growth in various hormone-dependent and castration-resistant prostate cancer models. The amino-terminal domain of AR docks at two sites on ELK1 to coactivate essential growth genes. This study explores the ability of small molecules to disrupt the ELK1-AR interaction in the spectrum of prostate cancer, inhibiting AR activity in a manner that would predict functional tumor selectivity. EXPERIMENTAL DESIGN: Small-molecule drug discovery and extensive biological characterization of a lead compound. RESULTS: We have discovered a lead molecule (KCI807) that selectively disrupts ELK1-dependent promoter activation by wild-type and variant ARs without interfering with ELK1 activation by ERK. KCI807 has an obligatory flavone scaffold and functional hydroxyl groups on C5 and C3'. KCI807 binds to AR, blocking ELK1 binding, and selectively blocks recruitment of AR to chromatin by ELK1. KCI807 primarily affects a subset of AR target growth genes selectively suppressing AR-dependent growth of prostate cancer cell lines with a better inhibitory profile than enzalutamide. KCI807 also inhibits in vivo growth of castration/enzalutamide-resistant cell line-derived and patient-derived tumor xenografts. In the rodent model, KCI807 has a plasma half-life of 6 hours, and maintenance of its antitumor effect is limited by self-induced metabolism at its 3'-hydroxyl. CONCLUSIONS: The results offer a mechanism-based therapeutic paradigm for disrupting the AR growth-promoting axis in the spectrum of prostate tumors while reducing global suppression of testosterone actions. KCI807 offers a good lead molecule for drug development.


Asunto(s)
Antagonistas de Receptores Androgénicos/farmacología , Antineoplásicos Hormonales/farmacología , Neoplasias de la Próstata/metabolismo , Receptores Androgénicos/metabolismo , Antagonistas de Receptores Androgénicos/química , Antagonistas de Receptores Androgénicos/uso terapéutico , Animales , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/uso terapéutico , Línea Celular Tumoral , Modelos Animales de Enfermedad , Descubrimiento de Drogas/métodos , Ensayos de Selección de Medicamentos Antitumorales , Perfilación de la Expresión Génica , Ensayos Analíticos de Alto Rendimiento , Humanos , Masculino , Ratones , Regiones Promotoras Genéticas , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Unión Proteica , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína Elk-1 con Dominio ets/metabolismo
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