RESUMEN
Background Treatment related problems are any event or circumstance involving patient treatment that actually or potentially interferes with an optimum outcome for a patient. Hemodialysis patients have on average 5-6 comorbid conditions and require 8-12 medications each day making them vulnerable to treatment related problems. Objective This study aimed to investigate treatment related problems affecting Jordanian hemodialysis patients, as well as assessing the factors associated with them. Setting Three hemodialysis centers in Jordan. Method A cross sectional multi-centered study was conducted. Direct interviews and patient files were used to collect patient information. A validated data collection form was used. Main outcome measure The average number of treatment related problems per patient. Results 160 patients from three different Jordanian dialysis centers were included. The cohort was 53 ± 15.2 years old, been on dialysis for 5.9 ± 5.3 years, had 3.9 ± 1.8 comorbid conditions and took 10.2 ± 2.8 different medications. There were a total of 1018 treatment related problems, a treatment related problem occurred once every 1.47 drug exposures. Adverse events were the most commonly occurring treatment related problems (27%), followed by indication related errors and dosing errors (24% and 21%, respectively). The number of treatment related problems is positively associated with age, the number of comorbid conditions, the number of hospital admissions in the previous year and the number of medications taken by the patient. Conclusion In the Jordanian hemodialysis population, treatment related problems affect virtually all patients. Most patients suffered adverse drug events and/or had drug indication problems. The number of treatment related problems correlated positively with age and the number of medications taken by the patient. Those with more treatment related problems also had higher hospital admissions and longer admission periods. Serious measures should be made in order to reduce the number of treatment related problems affecting this vulnerable population.
Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Fallo Renal Crónico , Atención Ambulatoria , Estudios Transversales , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/diagnóstico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Humanos , Diálisis Renal/efectos adversosRESUMEN
BACKGROUND AND PURPOSE: Selective androgen receptor modulators are of great value in the treatment of prostate cancer. The purpose of this study was to provide a preliminary characterization of a new class of non-steroidal androgen receptor modulators discovered in a high-throughput screening campaign. EXPERIMENTAL APPROACH: Competitive receptor binding, luciferase-based reporter methods, cell proliferation and in vivo assays were employed to evaluate an initial set of compounds from chemistry efforts. KEY RESULTS: Forty-nine analogues from the chemistry efforts showed high affinity binding to androgen receptors, agonist and/or antagonist activities in both CV-1 and MDA-MB-453 transfection assays. A proliferation assay in LNCaP cells also exhibited this profile. A representative of these non-steroidal compounds (compound 21) was devoid of activity at other nuclear receptors (oestrogen, progesterone, glucocorticoid and mineralocorticoid receptors) in the CV-1 co-transfection assay. At the same time, in an immature castrated rat model, it behaved as an androgen receptor antagonist against the growth of prostate, seminal vesicles and levator ani induced by exogenous androgen. Separation of compound 21 into its enantiomers showed that nearly all the androgen receptor modulating activity and binding resided in the dextrorotatory compound (23) while the laevorotatory isomer (22) possessed weak or little effect depending on the cell type studied. CONCLUSIONS AND IMPLICATIONS: These non-steroidal compounds may represent a new class of androgen receptor modulators for the treatment of not only prostate cancer but other clinical conditions where androgens and androgen receptors are involved in the pathological processes.
Asunto(s)
Antagonistas de Andrógenos/farmacología , Antagonistas de Receptores Androgénicos , Antineoplásicos Hormonales/farmacología , Diseño de Fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Antagonistas de Andrógenos/química , Antagonistas de Andrógenos/metabolismo , Antagonistas de Andrógenos/uso terapéutico , Anilidas/farmacología , Animales , Antineoplásicos Hormonales/química , Antineoplásicos Hormonales/metabolismo , Antineoplásicos Hormonales/uso terapéutico , Unión Competitiva , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Genes Reporteros , Humanos , Masculino , Ratones , Modelos Moleculares , Estructura Molecular , Nitrilos/farmacología , Orquiectomía , Proyectos Piloto , Próstata/efectos de los fármacos , Próstata/crecimiento & desarrollo , Próstata/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Unión Proteica , Ratas , Ratas Sprague-Dawley , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Reproducibilidad de los Resultados , Vesículas Seminales/efectos de los fármacos , Vesículas Seminales/crecimiento & desarrollo , Vesículas Seminales/metabolismo , Bibliotecas de Moléculas Pequeñas , Estereoisomerismo , Relación Estructura-Actividad , Testosterona/metabolismo , Compuestos de Tosilo/farmacología , Activación Transcripcional/efectos de los fármacos , TransfecciónRESUMEN
Benzofused heterocyclic analogs of the RXR selective modulator 1 (LG101506) were synthesized, and tested for their ability to bind RXRalpha and activate RXR homo and heterodimers. Potency and efficacy were observed to be dependent upon the choice of heterocycle as well as the sidechain employed.
Asunto(s)
Compuestos Heterocíclicos con 3 Anillos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/farmacología , Receptores X Retinoide/química , Animales , Benceno/química , Línea Celular , Chlorocebus aethiops , Diseño de Fármacos , Humanos , PPAR gamma , Unión Proteica , Receptor alfa X Retinoide/agonistas , Receptor alfa X Retinoide/antagonistas & inhibidores , Receptor alfa X Retinoide/química , Receptor gamma X Retinoide/agonistas , Receptor gamma X Retinoide/antagonistas & inhibidores , Receptor gamma X Retinoide/química , Receptores X Retinoide/agonistas , Receptores X Retinoide/antagonistas & inhibidores , Relación Estructura-Actividad , Activación Transcripcional/efectos de los fármacosRESUMEN
Fluorinated trienoic acid analogues of the RXR selective modulator 1 (LG101506) were synthesized, and tested for their ability to bind RXRalpha and activate RXR homo and heterodimers. Potency and efficacy were observed to be dependent upon the position of fluorination, and improvement in pharmacological profile was demonstrated in some cases.
Asunto(s)
Compuestos de Flúor/síntesis química , Compuestos de Flúor/metabolismo , Receptores de Ácido Retinoico/metabolismo , Factores de Transcripción/metabolismo , Tretinoina/síntesis química , Tretinoina/metabolismo , Animales , Diseño de Fármacos , Compuestos de Flúor/farmacología , Masculino , Ratones , Ratones Endogámicos ICR , Receptores X Retinoide , Retinoides/síntesis química , Retinoides/metabolismo , Retinoides/farmacología , Tretinoina/farmacologíaRESUMEN
Previous data have shown that RXR-selective agonists (e.g., 3 and 4) are insulin sensitizers in rodent models of non-insulin-dependent diabetes mellitus (NIDDM). Unfortunately, they also produce dramatic increases in triglycerides and profound suppression of the thyroid hormone axis. Here we describe the design and synthesis of new RXR modulators that retain the insulin-sensitizing activity of RXR agonists but produce substantially reduced side effects. These molecules bind selectively and with high affinity to RXR and, unlike RXR agonists, do not activate RXR homodimers. To further evaluate the antidiabetic activity of these RXR modulators, we have designed a concise and systematic structure-activity relationship around the 2E,4E,6Z-7-aryl-3-methylocta-2,4,6-trienoic acid scaffold. Selected compounds have been evaluated using insulin-resistant rodents (db/db mice) to characterize effects on glucose homeostasis. Our studies demonstrate the effectiveness of RXR modulators in lowering plasma glucose in the db/db mouse model.
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Caprilatos/síntesis química , Diabetes Mellitus Tipo 2/sangre , Hipoglucemiantes/síntesis química , Receptores de Ácido Retinoico/efectos de los fármacos , Factores de Transcripción/efectos de los fármacos , Animales , Glucemia/análisis , Caprilatos/química , Caprilatos/farmacología , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Resistencia a la Insulina , Masculino , Ratones , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley , Receptores de Ácido Retinoico/metabolismo , Receptores X Retinoide , Relación Estructura-Actividad , Factores de Transcripción/metabolismoRESUMEN
Novel 6-aryl benzimidazolones and benzothiazolones were prepared and examined as bioisosteres of the recently reported 6-aryl dihydroquinolines (1) for progesterone receptor (PR) antagonist activities. PR antagonist activities increased when compounds 9c-f possessed a more lipophilic group at position-1 and pendent aryl moiety para to NH moiety. Furthermore, conversion of carbonyl moiety of 9e,f to the thio-carbonyl led to benzoimidazolethiones 15a,b with significantly improved potency and binding affinity.
Asunto(s)
Bencimidazoles/síntesis química , Receptores de Progesterona/antagonistas & inhibidores , Bencimidazoles/química , Bencimidazoles/farmacología , Relación Estructura-ActividadRESUMEN
To review a population-controlled single institution experience with intraductal papillary mucinous tumors (IPMTs) of the pancreas treated in the United States and generate an incidence of this recently described disease process.First decribed in 1982, mucin-secreting pancreatic cancer constituted a newly recognized category of pancreatic exocrine tumors distinct from mucinous cystic neoplasms. Since that time, several small series of IPMTs of the pancreas have been reported. Most studies come from Asia and Europe, with limited data from American institutions and no description of the incidence.The authors retrospectively reviewed all patients who underwent pancreatic resections at Madigan Army Medical Center from October 1992 through November 1999. Cases suggestive of IPMTs underwent re-examination by a staff pathologist. Clinical presentation, imaging studies, treatment, histopathology, and outcomes were reviewed for those with IPMTs. The data base of all patients eligible for care was evaluated to obtain a population denominator and determine an incidence for this neoplasm.Over 7 years, 78 patients underwent pancreatic resections. Forty-two had pancreatic neoplasms and, of those, 8 (19%) had IPMTs. The mean age was 67 years, with equal numbers of males and females. All patients were symptomatic (abdominal pain, 75%; jaundice, 25%; weight loss, 25%). Abnormal computed tomography scans were noted in 7/8 (88%) cases. Mucin was visualized during endoscopic retrograde cholangiopancreatography in 5/7 (71%) patients. Preoperative diagnosis of IPMT was made in 5 (62%) cases. The locations of the tumors were head (63%), tail (12%), head and body (12%), and body and tail (12%). All lesions were resectable, and procedures included 5 pancreatoduodenectomies, 2 distal pancreatectomies, and 1 total pancreatectomy. Main duct tumors were noted in 63%, whereas the remainder had both main and branch duct lesions. Tumor invasion was discovered in 2 (25%) cases. Mean follow-up was 29 months. Those without invasion were all alive (follow-up, 6 to 86 months). One patient with tumor invasion died 4 months after surgery and the other was living 20 months later. The incidence of IPMTs was 1 case/281,000 patients/year.The incidence of IPMTs of the pancreas may be higher than previously recognized. Aggressive resection is warranted based on the favorable prognosis of patients without tumor invasion.
RESUMEN
Peroxisome proliferator-activated receptor-gamma (PPARgamma) agonists such as the thiazolidinediones are insulin sensitizers used in the treatment of type 2 diabetes. These compounds induce adipogenesis in cell culture models and increase weight gain in rodents and humans. We have identified a novel PPARgamma ligand, LG100641, that does not activate PPARgamma but selectively and competitively blocks thiazolidinedione-induced PPARgamma activation and adipocyte conversion. It also antagonizes target gene activation as well as repression in agonist-treated 3T3-L1 adipocytes. This novel PPARgamma antagonist does not block adipocyte differentiation induced by a ligand for the retinoid X receptor (RXR), the heterodimeric partner for PPARgamma, or by a differentiation cocktail containing insulin, dexamethasone, and 1-methyl-3-isobutylxanthine. Surprisingly, LG100641, like the PPARgamma agonist rosiglitazone, increases glucose uptake in 3T3-L1 adipocytes. Such selective PPARgamma antagonists may help determine whether insulin sensitization by thiazolidinediones is mediated solely through PPARgamma activation, and whether there are PPARgamma-ligand-independent pathways for adipocyte differentiation. If selective PPARgamma modulators block adipogenesis in vivo, they may prevent obesity, lower insulin resistance, and delay the onset of type 2 diabetes.
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Adipocitos/citología , Adipocitos/fisiología , Benzoatos/farmacología , Glucosa/metabolismo , Naftalenos/farmacología , Receptores Citoplasmáticos y Nucleares/fisiología , Tiazoles/farmacología , Tiazolidinedionas , Factores de Transcripción/fisiología , 1-Metil-3-Isobutilxantina/farmacología , Células 3T3 , Adipocitos/efectos de los fármacos , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Dexametasona/farmacología , Humanos , Hipoglucemiantes/farmacología , Insulina/farmacología , Cinética , Ligandos , Ratones , Proteínas Nucleares/fisiología , Receptores Citoplasmáticos y Nucleares/agonistas , Receptores Citoplasmáticos y Nucleares/antagonistas & inhibidores , Receptores de Ácido Retinoico/efectos de los fármacos , Receptores de Ácido Retinoico/fisiología , Proteínas Recombinantes/metabolismo , Receptores X Retinoide , Rosiglitazona , Factores de Transcripción/agonistas , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/efectos de los fármacos , Transfección , Triglicéridos/metabolismo , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Synthesis and biological evaluation of 6-thiophene 1,2-dihydro or 1,2,3,4-tetrahydroquinoline derivatives resulted in a number of potent nonsteroidal antiprogestins.
Asunto(s)
Quinolinas/síntesis química , Receptores de Progesterona/antagonistas & inhibidores , Tiofenos/síntesis química , Animales , Neoplasias de la Mama/metabolismo , Línea Celular , Reacciones Cruzadas , Fibroblastos , Haplorrinos , Humanos , Ratones , Quinolinas/farmacología , Receptores de Progesterona/genética , Relación Estructura-Actividad , Tiofenos/farmacología , Transfección , Células Tumorales CultivadasRESUMEN
The nm23 gene has been implicated as a suppressor gene involved in the control of the metastatic process of malignant cells. Reduced levels of nm23 gene product have been found in tumor cells with high metastatic potential such as several types of rodent tumors and human breast, colorectal, and lung carcinoma. This pilot study examines the expression of the nm23 gene product compared with nodal status in 70 consecutive patients with squamous cell carcinomas of the head and neck. Immunohistochemical staining was carried out on these tumor tissues with a monoclonal antibody to nm23-H1 peptide sequence. The tissues were scored from 0 to 2 by 2 independent observers. Reduced immunoreactivity, grades 0 and 1, was observed in 30 patients with positive nodal status (N = 34, 88%). Strong immunoreactivity, grade 2, was observed in 20 patients with negative nodal status (N = 36, 56%). Reduced expression of nm23 gene product was observed in patients with positive lymph node metastasis (P = 0. 0006, chi(2)). However, no significant differences in survival of these groups based on nm23 expression could be shown with the Kaplan-Meier analysis. This initial finding in the difference of nm23 gene product expression in patients with differing lymph node status is exciting but must be further validated with future studies.
Asunto(s)
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/secundario , Genes Supresores de Tumor , Neoplasias de Cabeza y Cuello/genética , Proteínas de Unión al GTP Monoméricas/análisis , Nucleósido-Difosfato Quinasa , Factores de Transcripción/análisis , Carcinoma de Células Escamosas/mortalidad , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Humanos , Inmunohistoquímica , Metástasis Linfática , Nucleósido Difosfato Quinasas NM23 , Proyectos Piloto , Tasa de SupervivenciaRESUMEN
Autoimmune enteropathy is an increasingly recognized cause of severe protracted diarrhea, usually affecting infants and children predisposed to autoimmune phenomena. Although this may be a common cause of diarrheal illness, it is scarcely recognized in the American literature. In association with thymoma, a case of so-called graft-vs-host-like colitis and 2 cases of chronic diarrhea associated with thymoma were reported, but, to our knowledge, no cases of autoimmune enteropathy have been reported as such. We describe 2 adults with autoimmune enteropathy found in association with a thymoma.
Asunto(s)
Enfermedades Autoinmunes/inmunología , Enfermedades Intestinales/inmunología , Timoma/inmunología , Neoplasias del Timo/inmunología , Apoptosis , Enfermedades Autoinmunes/patología , Biopsia , Diarrea/inmunología , Coagulación Intravascular Diseminada/etiología , Resultado Fatal , Femenino , Humanos , Enfermedades Intestinales/patología , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Nutrición Parenteral Total , Síndrome de Dificultad Respiratoria/etiología , Timectomía , Timoma/cirugía , Neoplasias del Timo/cirugía , Pérdida de PesoRESUMEN
BACKGROUND: The secosteroid 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) acts through the vitamin D receptor (VDR) to elicit many activities that make it a promising drug candidate for the treatment of a number of diseases, including cancer and psoriasis. Clinical use of 1,25(OH)2D3 has been limited by hypercalcemia elicited by pharmacologically effective doses. We hypothesized that structurally distinct, nonsecosteroidal mimics of 1,25(OH)2D3 might have different activity profiles from vitamin D analogs, and set out to discover such compounds by screening small-molecule libraries. RESULTS: A bis-phenyl derivative was found to activate VDR in a transactivation screening assay. Additional related compounds were synthesized that mimicked various activities of 1,25(OH)2D3, including growth inhibition of cancer cells and keratinocytes, as well as induction of leukemic cell differentiation. In contrast to 1, 25(OH)2D3, these synthetic compounds did not demonstrate appreciable binding to serum vitamin D binding protein, a property that is correlated with fewer calcium effects in vivo. Two mimics tested in mice showed greater induction of a VDR target gene with less elevation of serum calcium than 1,25(OH)2D3. CONCLUSIONS: These novel VDR modulators may have potential as therapeutics for cancer, leukemia and psoriasis with less calcium mobilization side effects than are associated with secosteroidal 1,25(OH)2D3 analogs.
Asunto(s)
Antineoplásicos/farmacología , Calcio/metabolismo , Receptores de Calcitriol/fisiología , Vitamina D/farmacología , Animales , Transporte Biológico , Neoplasias de la Mama/patología , Calcitriol/farmacología , Agonistas de los Canales de Calcio/farmacología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Femenino , Células HL-60 , Humanos , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Cetonas/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Imitación Molecular , Éteres Fenílicos/farmacología , Neoplasias de la Próstata/patología , Ratas , Receptores de Calcitriol/metabolismo , Activación Transcripcional , Vitamina D/análogos & derivados , Vitamina D/síntesis química , Proteína de Unión a Vitamina D/metabolismoRESUMEN
Optimization of the 1,2-dihydroquinoline A-ring of a nonsteroidal human progesterone receptor (hPR) agonist pharmacophore (1) was performed by using the cotransfection and receptor binding assays as guides. The 3-keto group was discovered to regain the potent agonist activity which was lost upon removal of the 3,4-olefin, and it led to a novel hPR agonist series, 5-aryl-1,2,3,4-tetrahydrochromeno[3, 4-f]quinolin-3-ones. The new progestins demonstrated potent hPR agonist activity in the cotransfection assay and high binding affinity similar to progesterone. T47D human breast cancer cell line was employed for further characterization of the new progestins and a number of reference analogues. It was found that the new 3-keto analogues showed full agonist activity in the T47D assay, while the reference compounds from other related nonsteroidal hPR agonist series exhibited only partial agonist activity.
Asunto(s)
Quinolonas/síntesis química , Receptores de Progesterona/agonistas , Animales , Unión Competitiva , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular , Chlorocebus aethiops , Humanos , Ligandos , Quinolonas/química , Quinolonas/farmacología , Receptores de Progesterona/biosíntesis , Relación Estructura-Actividad , Células Tumorales CultivadasRESUMEN
We have identified two novel compounds (RTI 3021-012 and RTI 3021-022) that demonstrate similar affinities for human progesterone receptor (PR) and display equivalent antiprogestenic activity. As with most antiprogestins, such as RU486, RTI 3021-012, and RTI 3021-022 also bind to the glucocorticoid receptor (GR) with high affinity. Unexpectedly, when compared with RU486, the RTI antagonists manifest significantly less GR antagonist activity. This finding indicates that, with respect to antiglucocorticoid function, receptor binding affinity is not a good predictor of biological activity. We have determined that the lack of a clear correlation between the GR binding affinity of the RTI compounds and their antagonist activity reflects the unique manner in which they modulate GR signaling. Previously, we proposed a two step "active inhibition" model to explain steroid receptor antagonism: 1) competitive inhibition of agonist binding; and 2) competition of the antagonist bound receptor with that activated by agonists for DNA response elements within target gene promoters. Accordingly, we observed that RU486, RTI 3021-012, and RTI 3021-022, when assayed for PR antagonist activity, accomplished both of these steps. Thus, all three compounds are "active antagonists" of PR function. When assayed on GR, however, RU486 alone functioned as an active antagonist. RTI 3021-012 and RTI 3021-022, on the other hand, functioned solely as "competitive antagonists" since they were capable of high affinity GR binding, but the resulting ligand receptor complex was unable to bind DNA. These results have important pharmaceutical implications supporting the use of mechanism based approaches to identify nuclear receptor modulators. Of equal importance, RTI 3021-012 and RTI 3021-022 are two new antiprogestins that may have clinical utility and are likely to be useful as research reagents with which to separate the effects of antiprogestins and antiglucocorticoids in physiological systems.
Asunto(s)
Estrenos/farmacología , Antagonistas de Hormonas/farmacología , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Progesterona/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Línea Celular , Células HeLa , Humanos , Ligandos , Mifepristona/farmacología , Regiones Promotoras Genéticas , Receptores de Glucocorticoides/genética , Receptores de Progesterona/genética , Transcripción GenéticaRESUMEN
Human estrogen receptor-alpha (hERalpha) or -beta (hERbeta) transfected into Hep G2 or COS1 cells each responded to estrogen to increase transcription from an estrogen-responsive element (ERE)-driven reporter vector with similar fold induction through a classical mechanism involving direct receptor binding to DNA. ER antagonists inhibited this estrogen induction through both hERalpha and hERbeta, although raloxifene was more potent through ERalpha than ERbeta, and tamoxifen was more potent via ERbeta than ERalpha. We have shown previously that estrogen stimulated the human retinoic acid receptor-alpha-1 (hRARalpha-1) promoter through nonclassical EREs by a mechanism that was ERalpha dependent, but that did not involve direct receptor binding to DNA. We show here that in contrast to hERalpha, hERbeta did not induce reporter activity driven by the hRARalpha-1 promoter in the presence of estrogen. While hERbeta did not confer estrogen responsiveness on this promoter, it did elicit transcriptional activation in the presence of 4-hydroxytamoxifen (4-OH-Tam). Additionally, this 4-OH-Tam agonist activity via ERbeta was completely blocked by estrogen. Like ERalpha, transcriptional activation of this promoter by ERbeta was not mediated by direct receptor binding to DNA. While hERalpha was shown to act through two estrogen-responsive sequences within the promoter, hERbeta acted only at the 3'-region, through two Sp1 sites, in response to 4-OH-Tam. Other ER antagonists including raloxifene, ICI-164,384 and ICI-182,780 also acted as agonists through ERbeta via the hRARalpha-1 promoter. Through the use of mutant and chimeric receptors, it was shown that the 4-OH-Tam activity via ERbeta from the hRARalpha-1 promoter in Hep G2 cells required the amino-terminal region of ERbeta, a region that was not necessary for estrogen-induced ERbeta activity from an ERE in Hep G2 cells. Additionally, the progesterone receptor (PR) antagonist RU486 acted as a weak (IC50 >1 microM) antagonist via hERalpha and as a fairly potent (IC50 approximately 200 nM) antagonist via hERbeta from an ERE-driven reporter in cells that do not express PR. Although RU486 bound only weakly to ERalpha or ERbeta in vitro, it did bind to ERbeta in whole-cell binding assays, and therefore, it is likely metabolized to an ERbeta-interacting compound in the cell. Interestingly, RU486 acted as an agonist through ERbeta to stimulate the hRARalpha-1 promoter in Hep G2 cells. These findings may have ramifications in breast cancer treatment regimens utilizing tamoxifen or other ER antagonists and may explain some of the known estrogenic or antiestrogenic biological actions of RU486.
Asunto(s)
Antagonistas de Estrógenos/farmacología , Estrógenos/farmacología , Receptores de Estrógenos/metabolismo , Receptores de Ácido Retinoico/genética , Tamoxifeno/farmacología , Animales , Secuencia de Bases , Sitios de Unión , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Receptor alfa de Estrógeno , Receptor beta de Estrógeno , Vectores Genéticos , Humanos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Receptores de Estrógenos/genética , Receptores de Ácido Retinoico/metabolismo , Elementos de Respuesta , Receptor alfa de Ácido Retinoico , Factor de Transcripción Sp1/metabolismo , Tamoxifeno/análogos & derivados , Transcripción Genética , Activación TranscripcionalRESUMEN
Thromboxane A2 (TxA2) receptors belong to the class of G-protein-coupled receptors. Knowledge of the relationship of structure to function for TxA2 receptors is limited because of their low levels of expression, lengthy purification procedures and poor recoveries. A C-terminal hexahistidine-tag (C-His) was ligated to the alpha-isoform of TxA2 receptors and expressed in COS-7 and Chinese hamster ovary cells. The C-His-TxA2 receptors bound the radioligands 125I-7-[(1R,2S,3S,5R)-6, 6-dimethyl-3-(4-benzenesulfonylamino)bicyclo[3.1. 1]hept-2-yl]-5(Z)-heptenoic acid, an antagonist, and 125I-[1S-1alpha, 2beta(5Z),3alpha(1E,3S*), 4alpha]-7-[3[(3-hydroxy-4-(4'-phenoxy)-1butenyl)-7-oxabicycl o-[2.2. 1]heptan-2-yl]-5-heptanoic acid, an agonist, with affinities not significantly different from those of the wild type (wt)-TxA2 receptors. LipofectAMINE transfection of the cDNAs resulted in high levels of expression (Bmax = 95 +/- 6 pmol/mg) of the C-His-TxA2 receptors. In competition binding studies the IC50 values of five different ligands were not significantly different between C-His-TxA2 and wt-TxA2 receptors. Agonist-induced stimulation of cAMP and total inositol phosphate formation were not significantly different between the two receptors. Purification on a Ni2+-NTA column resulted in a rapid (within 4 h) purification with a 36 +/- 2% recovery and a 30 +/- 6-fold purification (n = 5). The partially purified receptors were resolved on SDS-polyacrylamide gel electrophoresis, transferred to a nitrocellulose membrane, dissolved in acetone/trifluoroacetic acid/hexafluoroisopropanol/sinapinic acid, and successfully subjected to matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis. The results suggest that the combination of a high level of expression of C-His-TxA2 receptors and a rapid purification procedure followed by SDS- polyacrylamide gel electrophoresis may provide a useful approach for mass-spectrometry based structure-function and other studies of TxA2 receptors.
Asunto(s)
Histidina/metabolismo , Receptores de Tromboxanos/genética , Marcadores de Afinidad , Animales , Unión Competitiva , Western Blotting , Células CHO , Células COS , Cricetinae , AMP Cíclico/biosíntesis , ADN Complementario , Electroforesis en Gel de Poliacrilamida , Inositol 1,4,5-Trifosfato/biosíntesis , Ensayo de Unión Radioligante , Receptores de Tromboxanos/aislamiento & purificación , Receptores de Tromboxanos/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
The development of a novel class of nonsteroidal human progesterone receptor (hPR) agonists, 5-aryl-1,2-dihydro-5H-chromeno[3,4-f]quinolines 2, is described. The introduction of a 5-aryl group into the 1,2-dihydrocoumarino[3,4-f]quinoline core 1 is the key for progestational activities. The structure-activity relationship (SAR) studies of the 5-aryl substituents generated a series of potent hPR agonists, which exhibited similar biological activity (EC50 = 8-30 nM) to the natural hormone progesterone (EC50 = 2.9 nM) in cell-based assays with efficacies ranging from 28% to 96%. Most of the analogues displayed similar or greater binding affinity (Ki = 0.41-3.6 nM) than progesterone (Ki = 3.5 nM). Three representative analogues (13, 15, and 24) demonstrated in vivo activities in mammary gland morphology/uterine wet weight assay in ovariectomized rats.
Asunto(s)
Quinolinas/farmacología , Receptores de Progesterona/agonistas , Animales , Unión Competitiva , Femenino , Humanos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Glándulas Mamarias Animales/efectos de los fármacos , Glándulas Mamarias Animales/metabolismo , Quinolinas/química , Quinolinas/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Relación Estructura-Actividad , Útero/efectos de los fármacos , Útero/metabolismoRESUMEN
Several 5-(4-chlorophenyl)-1,2-dihydro-5H-chromeno[3,4-f]quinolines were prepared to determine the effects of substitution at C(8) and C(9) on the progestational activity of this pharmacophore. In combination with a halogen (F or Cl) at C(9), replacement of the C(5) aryl group with variously substituted aryl groups resulted in optimization of the progestational activity, affording compounds with in vitro activity greater than that of progesterone as measured by a cotransfection assay using human progesterone receptor subtype-B (hPR-B). Binding affinities (Ki) to hPR-A were subnanomolar in many cases. These in vitro effects were verified in vivo using a rodent model. Compound 10 (LG120794, 9-chloro-5-(4-chlorophenyl)-1,2-dihydro-2,2,4-trimethyl-5H-chromeno++ +[3,4-f] quinoline) was more potent than medroxyprogesterone acetate at counterpoising the effects of estradiol benzoate in the uterine wet weight assay using immature rats.
Asunto(s)
Quinolinas/farmacología , Receptores de Progesterona/agonistas , Animales , Línea Celular , Femenino , Humanos , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Quinolinas/química , Quinolinas/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Progesterona/metabolismo , Relación Estructura-Actividad , Útero/efectos de los fármacos , Útero/metabolismoRESUMEN
A series of nonsteroidal human progesterone receptor (hPR) agonists, 5-alkyl 1,2-dihydrochromeno[3,4-f]quinolines, was synthesized and evaluated in cotransfection and competitive receptor binding assays. The 5-alkyl substitution was shown to be responsible for the agonist activity and substitution at C9 dramatically enhanced the potency. A number of analogues in this series showed activities similar to or better than progesterone in the cotransfection and binding assays and analogue 15 exhibited similar in vivo activity as medroxyprogesterone acetate (MPA) in murine uterine wet weight/mammary gland morphology assays.
Asunto(s)
Quinolinas/síntesis química , Receptores de Progesterona/efectos de los fármacos , Animales , Humanos , Quinolinas/farmacología , Ratas , Receptores de Progesterona/agonistas , Receptores de Progesterona/antagonistas & inhibidores , Relación Estructura-ActividadRESUMEN
A novel series of oxazolecarboxamide-substituted omega-phenyl-omega-(3-pyridyl)alkenoic acid derivatives was discovered as potent dual-acting agents to block the TXA2 receptor and to inhibit the thromboxane synthase (TRA/TSI). Synthesis, structure-activity relationship (SAR), and in vitro and in vivo pharmacology of this series of compounds are described. Modification of the series revolved around the oxazole moiety to increase the hydrophilicity of the compounds and to correlate the biological activity with lipophilicity of the compounds. The most potent in the series was (E)-7-[4-[4-[[(4-cyclohexylbutyl)amino]carbonyl]-2-oxazolyl] phenyl]-7 -(3-pyridyl)hept-6-enoic acid (14) with Kd = 9.9 +/- 0.4 nM for the thromboxane receptor antagonism and IC50 = 55.0 +/- 17.9 nM for thromboxane synthase inhibition. The compound 14 was a selective TRA/TSI which exhibited desirable characteristics for oral activity, "shunt" effect to elevate PGI2 level, and absence of agonist activity.