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This study assessed the impact of product particle sizes (fine: 106-500 µm; coarse: 500-1000 µm) on oxycodone pharmacokinetics (PK) following nasal insufflation of milled oxycodone extended-release (ER) abuse-deterrent (AD) tablets using immediate-release (IR) non-AD product as reference. Additionally, this study assessed the effects of different excipient to drug ratio (EDR) by comparing two products with fine particle size but different EDRs, again using IR non-AD as the control. Thirty milligrams of oxycodone were administered in each treatment. Coarsely milled 30 mg ER tablets demonstrated significantly lower maximum plasma concentration (Cmax ) and partial areas under the concentration-time curve (AUCs) than those of the finely milled IR tablets. Finely milled ER tablets demonstrated similar Cmax and partial AUCs but higher total systemic exposures than those of finely milled IR tablets. Finely milled 80 mg ER tablets were bioequivalent to IR tablet on all parameters. The finely milled 30 mg ER tablet was not bioequivalent to the coarsely milled 30 mg ER tablet and had higher values for all parameters. The finely milled 30 mg ER tablets (EDR 6.9) showed no PK differences with finely milled 80 mg ER tablets (EDR 4.9). No serious adverse events were reported. The study demonstrated a significant effect of particle sizes (106-1000 µm) on PK of milled and insufflated oxycodone ER AD tablets. EDR difference did not have any significant effects on the PK of finely milled oxycodone ER AD tablets. Particle size distribution should be considered when nasal AD properties of opioid drug products are investigated during drug development.
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Analgésicos Opioides/farmacocinética , Trastornos Relacionados con Opioides/etiología , Oxicodona/farmacocinética , Formulaciones Disuasorias del Abuso , Administración Intranasal , Adolescente , Adulto , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/efectos adversos , Área Bajo la Curva , Estudios Cruzados , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/efectos adversos , Preparaciones de Acción Retardada/farmacocinética , Femenino , Voluntarios Sanos , Humanos , Insuflación , Masculino , Persona de Mediana Edad , Oxicodona/administración & dosificación , Oxicodona/efectos adversos , Tamaño de la Partícula , Comprimidos , Adulto JovenRESUMEN
Purpose:fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) is present in 30% of acute myeloid leukemia (AML), and these patients have short disease-free survival. FLT3 inhibitors have limited and transient clinical activity, and concurrent treatment with inhibitors of parallel or downstream signaling may improve responses. The oncogenic serine/threonine kinase Pim-1 is upregulated downstream of FLT3-ITD and also promotes its signaling in a positive feedback loop, suggesting benefit of combined Pim and FLT3 inhibition.Experimental Design: Combinations of clinically active Pim and FLT3 inhibitors were studied in vitro and in vivoResults: Concurrent treatment with the pan-Pim inhibitor AZD1208 and FLT3 inhibitors at clinically applicable concentrations abrogated in vitro growth of FLT3-ITD, but not wild-type FLT3 (FLT3-WT), cell lines. AZD1208 cotreatment increased FLT3 inhibitor-induced apoptosis of FLT3-ITD, but not FLT3-WT, cells measured by sub-G1 fraction, annexin V labeling, mitochondrial membrane potential, and PARP and caspase-3 cleavage. Concurrent treatment with AZD1208 and the FLT3 inhibitor quizartinib decreased growth of MV4-11 cells, with FLT3-ITD, in mouse xenografts, and prolonged survival, enhanced apoptosis of FLT3-ITD primary AML blasts, but not FLT3-WT blasts or remission marrow cells, and decreased FLT3-ITD AML blast colony formation. Mechanistically, AZD1208 and quizartinib cotreatment decreased expression of the antiapoptotic protein Mcl-1. Decrease in Mcl-1 protein expression was abrogated by treatment with the proteasome inhibitor MG132, and was preceded by downregulation of the Mcl-1 deubiquitinase USP9X, a novel mechanism of Mcl-1 regulation in AML.Conclusions: The data support clinical testing of Pim and FLT3 inhibitor combination therapy for FLT3-ITD AML. Clin Cancer Res; 24(1); 234-47. ©2017 AACR.
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Apoptosis/genética , Duplicación de Gen , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogénicas c-pim-1/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/genética , Animales , Benzotiazoles/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Potencial de la Membrana Mitocondrial , Ratones , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Procesamiento Proteico-Postraduccional , Proteolisis , Proteoma/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Internal tandem duplication of fms-like tyrosine kinase-3 (FLT3-ITD) is frequent (30 percent) in acute myeloid leukemia (AML), and is associated with short disease-free survival following chemotherapy. The serine threonine kinase Pim-1 is a pro-survival oncogene transcriptionally upregulated by FLT3-ITD that also promotes its signaling in a positive feedback loop. Thus inhibiting Pim-1 represents an attractive approach in targeting FLT3-ITD cells. Indeed, co-treatment with the pan-Pim kinase inhibitor AZD1208 or expression of a kinase-dead Pim-1 mutant sensitized FLT3-ITD cell lines to apoptosis triggered by chemotherapy drugs including the topoisomerase 2 inhibitors daunorubicin, etoposide and mitoxantrone, but not the nucleoside analog cytarabine. AZD1208 sensitized primary AML cells with FLT3-ITD to topoisomerase 2 inhibitors, but did not sensitize AML cells with wild-type FLT3 or remission bone marrow cells, supporting a favorable therapeutic index. Mechanistically, the enhanced apoptosis observed with AZD1208 and topoisomerase 2 inhibitor combination treatment was associated with increased DNA double-strand breaks and increased levels of reactive oxygen species (ROS), and co-treatment with the ROS scavenger N-acetyl cysteine rescued FLT3-ITD cells from AZD1208 sensitization to topoisomerase 2 inhibitors. Our data support testing of Pim kinase inhibitors with topoisomerase 2 inhibitors, but not with cytarabine, to improve treatment outcomes in AML with FLT3-ITD.
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Daño del ADN , Leucemia Mieloide Aguda/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-pim-1/antagonistas & inhibidores , Inhibidores de Topoisomerasa II/farmacología , Tirosina Quinasa 3 Similar a fms/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/administración & dosificación , Compuestos de Bifenilo/farmacología , Citarabina/farmacología , Sinergismo Farmacológico , Humanos , Leucemia Mieloide Aguda/enzimología , Leucemia Mieloide Aguda/genética , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-pim-1/genética , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Tiazolidinas/administración & dosificación , Tiazolidinas/farmacología , Inhibidores de Topoisomerasa II/administración & dosificaciónRESUMEN
Gene expression in different tissues is often controlled by alternative promoters that result in the synthesis of mRNA with unique - usually untranslated - first exons. Bcrp1 (Abcg2), the murine orthologue of the ABC transporter Breast Cancer Resistance Protein (BCRP, ABCG2), has at least four alternative promoters that are designated by the corresponding four alternative first exons produced: E1U, E1A, E1B, and E1C. Herein, in-silico protocols are presented to predict alternative promoter usage for Bcrp1. Furthermore, reporter assay methods are described to produce reporter constructs for alternative promoters and to determine the functionality of putative promoters upstream of the alternative first exons that are identified.
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Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Regiones Promotoras Genéticas , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/biosíntesis , Animales , Secuencia de Bases , Exones , Regulación de la Expresión Génica , Humanos , Ratones , ARN Mensajero/biosíntesis , ARN Mensajero/genéticaRESUMEN
Selective targeting of the oxidative state, which is a tightly balanced fundamental cellular property, is an attractive strategy for developing novel anti-leukemic chemotherapeutics with potential applications in the treatment of acute myeloid leukemia (AML), a molecularly heterogeneous disease. Dimeric naphthoquinones (BiQs) with the ability to undergo redox cycling and to generate reactive oxygen species (ROS) in cancer cells are a novel class of compounds with unique characteristics that make them excellent candidates to be tested against AML cells. We evaluated the effect of two BiQ analogues and one monomeric naphthoquinone in AML cell lines and primary cells from patients. All compounds possess one halogen and one hydroxyl group on the quinone cores. Dimeric, but not monomeric, naphthoquinones demonstrated significant anti-AML activity in the cell lines and primary cells from patients with favorable therapeutic index compared to normal hematopoietic cells. BiQ-1 effectively inhibited clonogenicity and induced apoptosis as measured by Western blotting and Annexin V staining and mitochondrial membrane depolarization by flow cytometry. BiQ-1 significantly enhances intracellular ROS levels in AML cells and upregulates expression of key anti-oxidant protein, Nrf2. Notably, systemic exposure to BiQ-1 was well tolerated in mice. In conclusion, we propose that BiQ-induced therapeutic augmentation of ROS in AML cells with dysregulation of antioxidants kill leukemic cells while normal cells remain relatively intact. Further studies are warranted to better understand this class of potential chemotherapeutics.
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BACKGROUND: Hair strength depends on various factors such as nutrition, environmental factors, sunlight, oiling, aging, conditioner, etc. AIM: To compare the tensile strength and breaking point of the hair shaft between (1) vegetarian and nonvegetarian. (2) Those who regularly apply and those who do not apply oil. (3) Pigmented and nonpigmented hair, (4) childhood and elderly. MATERIALS AND METHODS: Hair fibers were mounted in tensile strength testing machine Zwick/Roell Z010 and gradual force was administered. The elongation of hair fiber in mm and the maximum force required to break the hair strand were recorded for each fiber. RESULTS: Elasticity of the children's hair was more than the elasticity of adult (P = 0.05) although tensile strength in children hair was not statistically significant (>0.05). Similarly, the tensile strength was more among those who regularly consumed nonvegetarian food but the difference was not statistically significant (P > 0.05). There was no statistically significant difference in other groups (P > 0.05). CONCLUSION: Elasticity in children hair is statistically more than elderly hair although there is no significant change in tensile strength.
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Phosphorylated cyclic-AMP (cAMP) response element binding protein (p-CREB) is a downstream effector of a variety of important signaling pathways. We investigated whether the human BCRP promoter contains a functional cAMP response element (CRE). 8Br-cAMP, a cAMP analogue, increased the activity of a BCRP promoter reporter construct and BCRP mRNA in human carcinoma cells. Epidermal growth factor receptor (EGFR) pathway activation also led to an increase in p-CREB and in BCRP promoter reporter activity via two major downstream EGFR signaling pathways: the phosphotidylinositol-3-kinase (PI3K)/AKT pathway and the mitogen-activated protein kinase (MAPK) pathway. EGF treatment increased the phosphorylation of EGFR, AKT, ERK and CREB, while simultaneously enhancing BCRP mRNA and functional protein expression. EGF-stimulated CREB phosphorylation and BCRP induction were diminished by inhibition of EGFR, PI3K/AKT or RAS/MAPK signaling. CREB silencing using RNA interference reduced basal levels of BCRP mRNA and diminished the induction of BCRP by EGF. Chromatin immunoprecipitation assays confirmed that a putative CRE site on the BCRP promoter bound p-CREB by a point mutation of the CRE site abolished EGF-induced stimulation of BCRP promoter reporter activity. Furthermore, the CREB co-activator, cAMP-regulated transcriptional co-activator (CRTC2), is involved in CREB-mediated BCRP transcription: androgen depletion of LNCaP human prostate cancer cells increased both CREB phosphorylation and CRTC2 nuclear translocation, and enhanced BCRP expression. Silencing CREB or CRTC2 reduced basal BCRP expression and BCRP induction under androgen-depletion conditions. This novel CRE site plays a central role in mediating BCRP gene expression in several human cancer cell lines following activation of multiple cancer-relevant signaling pathways.
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Transportadoras de Casetes de Unión a ATP/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , AMP Cíclico/genética , Receptores ErbB/genética , Proteínas de Neoplasias/genética , Transcripción Genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Andrógenos/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/antagonistas & inhibidores , Receptores ErbB/biosíntesis , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Fosforilación , Regiones Promotoras Genéticas , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Background Crenolanib (crenolanib besylate, 4-piperidinamine, 1-[2-[5-[(3-methyl-3-oxetanyl)methoxy]-1H-benzimidazol-1-yl]-8-quinolinyl]-, monobenzenesulfonate) is a potent and specific type I inhibitor of fms-like tyrosine kinase 3 (FLT3) that targets the active kinase conformation and is effective against FLT3 with internal tandem duplication (ITD) with point mutations induced by, and conferring resistance to, type II FLT3 inhibitors in acute myeloid leukemia (AML) cells. Crenolanib is also an inhibitor of platelet-derived growth factor receptor alpha and beta and is in clinical trials in both gastrointestinal stromal tumors and gliomas. Methods We tested crenolanib interactions with the multidrug resistance-associated ATP-binding cassette proteins ABCB1 (P-glycoprotein), ABCG2 (breast cancer resistance protein) and ABCC1 (multidrug resistance-associated protein 1), which are expressed on AML cells and other cancer cells and are important components of the blood-brain barrier. Results We found that crenolanib is a substrate of ABCB1, as evidenced by approximate five-fold resistance of ABCB1-overexpressing cells to crenolanib, reversal of this resistance by the ABCB1-specific inhibitor PSC-833 and stimulation of ABCB1 ATPase activity by crenolanib. In contrast, crenolanib was not a substrate of ABCG2 or ABCC1. Additionally, it did not inhibit substrate transport by ABCB1, ABCG2 or ABCC1, at pharmacologically relevant concentrations. Finally, incubation of the FLT3-ITD AML cell lines MV4-11 and MOLM-14 with crenolanib at a pharmacologically relevant concentration of 500 nM did not induce upregulation of ABCB1 cell surface expression. Conclusions Thus ABCB1 expression confers resistance to crenolanib and likely limits crenolanib penetration of the central nervous system, but crenolanib at therapeutic concentrations should not alter cellular exposure to ABC protein substrate chemotherapy drugs.
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Transportadoras de Casetes de Unión a ATP/metabolismo , Antineoplásicos/farmacología , Bencimidazoles/farmacología , Piperidinas/farmacología , Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transporte Biológico/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Ciclosporinas/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/metabolismo , Células Tumorales CultivadasRESUMEN
Alternative promoter usage is typically associated with mRNAs with differing first exons that contain or consist entirely of a 5' untranslated region. The murine Bcrp1 (Abcg2) transporter has three alternative promoters associated with mRNAs containing alternative untranslated first exons designated as E1A, E1B, and E1C. The E1B promoter regulates Bcrp1 transcription in mouse intestine. Here, we report the identification and characterization of a novel Bcrp1 promoter and first exon, E1U, located upstream from the other Bcrp1 promoters/first exons, which is the predominant alternative promoter utilized in murine testis. Using in silico analysis we identified a putative steroidogenic factor-1 (SF-1) response element that was unique to the Bcrp1 E1U alternative promoter. Overexpression of SF-1 in murine TM4 Sertoli cells enhanced Bcrp1 E1U mRNA expression and increased Bcrp1 E1U alternative promoter activity in a reporter assay, whereas mutation of the SF-1 binding site totally eliminated Bcrp1 E1U alternative promoter activity. Moreover, expression of Bcrp1 E1U and total mRNA and Bcrp1 protein was markedly diminished in the testes from adult Sertoli cell-specific SF-1 knockout mice, in comparison to the testes from wild-type mice. Binding of SF-1 to the SF-1 response element in the E1U promoter was demonstrated by chromatin immunoprecipitation assays. In conclusion, nuclear transcription factor SF-1 is involved with the regulation of a novel promoter of Bcrp1 that governs transcription of the E1U mRNA isoform in mice. The present study furthers understanding of the complex regulation of Bcrp1 expression in specific tissues of a mammalian model.
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Transportadoras de Casetes de Unión a ATP/genética , Proteínas de Unión al ADN/fisiología , Exones/genética , Regulación de la Expresión Génica , Regiones Promotoras Genéticas/genética , Células de Sertoli/metabolismo , Testículo/metabolismo , Factores de Transcripción/fisiología , Regiones no Traducidas 5' , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Western Blotting , Células Cultivadas , Inmunoprecipitación de Cromatina , Luciferasas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación/genética , Especificidad de Órganos , Factores de Empalme de ARN , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Elementos de Respuesta/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células de Sertoli/citología , Transcripción Genética/genética , TransfecciónRESUMEN
The type III receptor tyrosine kinase fms-like tyrosine kinase 3 (FLT3) is expressed on both normal hematopoietic stem cells and acute myeloid leukemia (AML) cells and regulates their proliferation. Internal tandem duplication (ITD) mutation of FLT3 is present in a third of AML cases, results in constitutive activation and aberrant signaling of FLT3, and is associated with adverse treatment outcomes. While wild-type (WT) FLT3 is predominantly a 150 kDa complex glycosylated cell surface protein, FLT3-ITD is partially retained in the endoplasmic reticulum as a 130 kDa underglycosylated species associated with the chaperones calnexin and heat shock protein (HSP) 90, and mediates aberrant STAT5 signaling, which upregulates the oncogenic serine/threonine kinase Pim-1. FLT3 contains a Pim-1 substrate consensus serine phosphorylation site, and we hypothesized that it might be a Pim-1 substrate. Pim-1 was indeed found to directly interact with and serine-phosphorylate FLT3. Pim-1 inhibition decreased the expression and half-life of 130 kDa FLT3, with partial abrogation by proteasome inhibition, in association with decreased FLT3 binding to calnexin and HSP90, and increased 150 kDa FLT3 expression and half-life, with abrogation by inhibition of glycosylation. These findings were consistent with Pim-1 stabilizing FLT3-ITD as a 130 kDa species associated with calnexin and HSP90 and inhibiting its glycosylation to form the 150 kDa species. Pim-1 knockdown effects were similar. Pim-1 inhibition also decreased phosphorylation of FLT3 at tyrosine 591 and of STAT5, and expression of Pim-1 itself, consistent with inhibition of the FLT3-ITD-STAT5 signaling pathway. Finally, Pim-1 inhibition synergized with FLT3 inhibition in inducing apoptosis of FLT3-ITD cells. This is, to our knowledge, the first demonstration of a role of Pim-1 in a positive feedback loop promoting aberrant signaling in malignant cells.
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Leucemia Mieloide Aguda/metabolismo , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal , Tirosina Quinasa 3 Similar a fms/metabolismo , Animales , Apoptosis , Calnexina/metabolismo , Línea Celular , Proliferación Celular , Retículo Endoplásmico/metabolismo , Glicosilación , Proteínas de Choque Térmico/metabolismo , Humanos , Ratones , Mutación , Fosforilación , Complejo de la Endopetidasa Proteasomal/metabolismo , Serina/metabolismo , Tirosina/metabolismoRESUMEN
The oral second-generation bis-aryl urea fms-like tyrosine kinase 3 (FLT3) inhibitor quizartinib (AC220) has favorable kinase selectivity and pharmacokinetics. It inhibits mutant and wild-type FLT3 in vivo at 0.1 and 0.5 µM, respectively, and has shown favorable activity and tolerability in phase I and II trials in acute myeloid leukemia, with QT prolongation as the dose-limiting toxicity. Co-administration with chemotherapy is planned. We characterized interactions of quizartinib with the ATP-binding cassette (ABC) proteins ABCB1 (P-glycoprotein) and ABCG2 (breast cancer resistance protein). Its effects on uptake of fluorescent substrates and apoptosis were measured by flow cytometry, binding to ABCB1 and ABCG2 drug-binding sites by effects on [¹²5I]iodoarylazidoprazosin ([¹²5I]-IAAP) photolabeling and ATPase activity, and cell viability by the WST-1 colorimetric assay. Quizartinib inhibited transport of fluorescent ABCG2 and ABCB1 substrates in ABCG2- and ABCB1-overexpressing cells in a concentration-dependent manner, from 0.1 to 5 µM and from 0.5 to 10 µM, respectively, and inhibited [¹²5I]-IAAP photolabeling of ABCG2 and ABCB1 with IC50 values of 0.07 and 3.3 µM, respectively. Quizartinib at higher concentrations decreased ABCG2, but not ABCB1, ATPase activity. Co-incubation with quizartinib at 0.1 to 1 µM sensitized ABCG2-overexpressing K562/ABCG2 and 8226/MR20 cells to ABCG2 substrate chemotherapy drugs in a concentration-dependent manner in cell viability and apoptosis assays. Additionally, quizartinib increased cellular uptake of the ABCG2 substrate fluoroquinolone antibiotic ciprofloxacin, which also prolongs the QT interval, in a concentration-dependent manner, predicting altered ciprofloxacin pharmacokinetics and pharmacodynamics when co-administered with quizartinib. Thus quizartinib inhibits ABCG2 at pharmacologically relevant concentrations, with implications for both chemosensitization and adverse drug interactions. These interactions should be considered in the design of treatment regimens combining quizartinib and chemotherapy drugs and in choice of concomitant medications to be administered with quizartinib.
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Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Benzotiazoles/efectos adversos , Benzotiazoles/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Compuestos de Fenilurea/efectos adversos , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacología , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/metabolismo , Absorción/efectos de los fármacos , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Benzotiazoles/administración & dosificación , Transporte Biológico/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Fluoroquinolonas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Corazón/efectos de los fármacos , Corazón/fisiología , Humanos , Proteínas de Neoplasias/metabolismo , Compuestos de Fenilurea/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificaciónRESUMEN
We report a 2-week-old neonate with a large congenital melanocytic nevus over face treated with surgical curettage followed by a combination of carbon dioxide laser and Q-switched neodymium-doped yttrium aluminum garnet lasers. The results were satisfactory with near complete resolution after 1 year of age. This case is reported to emphasize the timely management and the importance of curettage prior to development of rete ridges.
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Medical treatments for acne vulgaris include a variety of topical and oral medications. Poor compliance, lack of durable remission, and potential side effects are common drawbacks to these treatments. Therefore, there is a growing demand for a fast, safe, and side-effect-free novel therapy. Acne often improves after exposure to sunlight, and this has led to the development of laser and other light therapies resulting in the overall ease of treatment, with minimal adverse effects. A variety of light and laser devices has been used for the treatment of acne, including the potassium titanyl phosphate laser, the 585- and 595-nm pulsed dye lasers, the 1450-nm diode laser, radiofrequency devices, intense pulsed light sources, and photodynamic therapy using 5-aminolevulinic acid and indocyanine green. These devices are thought to target the underlying pathogenic factors such as propionibacterium acnes colonization, increased sebaceous gland activity, and the cutaneous inflammatory response. In this article, we review the current status of light- and laser-based treatment of acne.
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Acné Vulgar/tratamiento farmacológico , Acné Vulgar/terapia , Terapia por Láser/métodos , Fotoquimioterapia/métodos , HumanosRESUMEN
Overexpression of the ATP-binding cassette (ABC) drug efflux proteins P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2) on malignant cells is associated with inferior chemotherapy outcomes. Both, ABCB1 and ABCG2, are substrates of the serine/threonine kinase Pim-1; Pim-1 knockdown decreases their cell surface expression, but SGI-1776, the first clinically tested Pim inhibitor, was shown to reverse drug resistance by directly inhibiting ABCB1-mediated transport. We sought to characterize Pim-1-dependent and -independent effects of SGI-1776 on drug resistance. SGI-1776 at the Pim-1-inhibitory and non-cytotoxic concentration of 1 µM decreased the IC(50)s of the ABCG2 and ABCB1 substrate drugs in cytotoxicity assays in resistant cells, with no effect on the IC(50) of non-substrate drug, nor in parental cells. SGI-1776 also increased apoptosis of cells overexpressing ABCG2 or ABCB1 exposed to substrate chemotherapy drugs and decreased their colony formation in the presence of substrate, but not non-substrate, drugs, with no effect on parental cells. SGI-1776 decreased ABCB1 and ABCG2 surface expression on K562/ABCB1 and K562/ABCG2 cells, respectively, with Pim-1 overexpression, but not HL60/VCR and 8226/MR20 cells, with lower-level Pim-1 expression. Finally, SGI-1776 inhibited uptake of ABCG2 and ABCB1 substrates in a concentration-dependent manner irrespective of Pim-1 expression, inhibited ABCB1 and ABCG2 photoaffinity labeling with the transport substrate [(125)I]iodoarylazidoprazosin ([(125)I]IAAP) and stimulated ABCB1 and ABCG2 ATPase activity. Thus SGI-1776 decreases cell surface expression of ABCB1 and ABCG2 and inhibits drug transport by Pim-1-dependent and -independent mechanisms, respectively. Decrease in ABCB1 and ABCG2 cell surface expression mediated by Pim-1 inhibition represents a novel mechanism of chemosensitization.
Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Imidazoles/farmacología , Proteínas de Neoplasias/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Piridazinas/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Antineoplásicos/farmacología , Transporte Biológico/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Estructura Molecular , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas c-pim-1/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-pim-1/genéticaRESUMEN
Ponatinib is a novel tyrosine kinase inhibitor with potent activity against BCR-ABL with mutations, including T315I, and also against fms-like tyrosine kinase 3. We tested interactions between ponatinib at pharmacologically relevant concentrations of 50 to 200 nmol/L and the MDR-associated ATP-binding cassette (ABC) proteins ABCB1, ABCC1, and ABCG2. Ponatinib enhanced uptake of substrates of ABCG2 and ABCB1, but not ABCC1, in cells overexpressing these proteins, with a greater effect on ABCG2 than on ABCB1. Ponatinib potently inhibited [(125)I]-IAAP binding to ABCG2 and ABCB1, indicating binding to their drug substrate sites, with IC(50) values of 0.04 and 0.63 µmol/L, respectively. Ponatinib stimulated ABCG2 ATPase activity in a concentration-dependent manner and stimulated ABCB1 ATPase activity at low concentrations, consistent with it being a substrate of both proteins at pharmacologically relevant concentrations. The ponatinib IC(50) values of BCR-ABL-expressing K562 cells transfected with ABCB1 and ABCG2 were approximately the same as and 2-fold higher than that of K562, respectively, consistent with ponatinib being a substrate of both proteins, but inhibiting its own transport, and resistance was also attenuated to a small degree by ponatinib-induced downregulation of ABCB1 and ABCG2 cell-surface expression on resistant K562 cells. Ponatinib at pharmacologically relevant concentrations produced synergistic cytotoxicity with ABCB1 and ABCG2 substrate chemotherapy drugs and enhanced apoptosis induced by these drugs, including daunorubicin, mitoxantrone, topotecan, and flavopiridol, in cells overexpressing these transport proteins. Combinations of ponatinib and chemotherapy drugs warrant further testing.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Imidazoles/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Piridazinas/farmacología , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/metabolismo , Apoptosis/efectos de los fármacos , Carbocianinas/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clorofila/análogos & derivados , Clorofila/metabolismo , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Humanos , Concentración 50 Inhibidora , Mitoxantrona/farmacología , Proteínas de Neoplasias/metabolismo , Unión Proteica , Rodamina 123/metabolismo , Topotecan/farmacologíaRESUMEN
Since cloning of the ATP-binding cassette (ABC) family member breast cancer resistance protein (BCRP/ABCG2) and its characterization as a multidrug resistance efflux transporter in 1998, BCRP has been the subject of more than two thousand scholarly articles. In normal tissues, BCRP functions as a defense mechanism against toxins and xenobiotics, with expression in the gut, bile canaliculi, placenta, blood-testis and blood-brain barriers facilitating excretion and limiting absorption of potentially toxic substrate molecules, including many cancer chemotherapeutic drugs. BCRP also plays a key role in heme and folate homeostasis, which may help normal cells survive under conditions of hypoxia. BCRP expression appears to be a characteristic of certain normal tissue stem cells termed "side population cells," which are identified on flow cytometric analysis by their ability to exclude Hoechst 33342, a BCRP substrate fluorescent dye. Hence, BCRP expression may contribute to the natural resistance and longevity of these normal stem cells. Malignant tissues can exploit the properties of BCRP to survive hypoxia and to evade exposure to chemotherapeutic drugs. Evidence is mounting that many cancers display subpopulations of stem cells that are responsible for tumor self-renewal. Such stem cells frequently manifest the "side population" phenotype characterized by expression of BCRP and other ABC transporters. Along with other factors, these transporters may contribute to the inherent resistance of these neoplasms and their failure to be cured.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/fisiología , Resistencia a Antineoplásicos , Proteínas de Neoplasias/fisiología , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Barrera Hematoencefálica/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Resistencia a Múltiples Medicamentos , Femenino , Humanos , Proteínas de Neoplasias/antagonistas & inhibidores , Neoplasias/patologíaRESUMEN
Mouse models are often used to predict drug absorption in humans. Mouse Bcrp1 protein exhibits sequence and functional homology with human BCRP protein. Additionally, BCRP/Bcrp1 expression is regulated by alternative promoter usage in humans and mice; however, the precise intestine-specific alternative promoter utilized in either species is yet to be determined. Therefore we sought to identify and characterize the mouse intestinal Bcrp1 promoter. Using real-time quantitative RT-PCR and 5' RACE PCR we first established the predominance of a single Bcrp1 first exon (E1b) in the Bcrp1 mRNA isolated throughout the mouse intestine. Simultaneously using 5' RACE PCR we identified E1C as the predominant BCRP 5' UTR expressed in the human intestine. Next we established functional activity for the murine promoter upstream of E1b using reporter assays. Subsequently using deletion-construct analysis we found the core promoter region to span -231 to -42bps from the transcriptional start site of E1b. We then predicted a cAMP response element (CRE) as a transcription factor binding site unique only to the E1b promoter region, using in silico methods. We finally established functional interaction of phospho-CREB (p-CREB) protein with the CRE on the E1b promoter using both functional assays and chromatin immunoprecipitation assays. In conclusion, mouse intestinal Bcrp1 expression is regulated by a single alternative promoter upstream of E1b, the predominant Bcrp1 mRNA isoform expressed in the mouse intestine. Furthermore, Bcrp1 E1b mRNA expression is regulated by binding of p-CREB to its cis site on the mouse E1b promoter region.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/biosíntesis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Regulación de la Expresión Génica/fisiología , ARN Mensajero/biosíntesis , Elementos de Respuesta/fisiología , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Animales , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Exones/fisiología , Humanos , Ratones , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Especificidad de Órganos/fisiología , ARN Mensajero/genética , Especificidad de la EspecieRESUMEN
Extra ocular Sebaceous Carcinoma is a rare malignancy when compared to Peri ocular variant and these are derived from sebaceous gland epithelium. The aggressive types of extra ocular sebaceous neoplasm are reported with lymph node and visceral metastasis associated with poor prognosis. Here we report a case of extensive cutaneous extra ocular sebaceous cell carcinoma confined to large area of scalp proven by Immunohistochemistry without intra cranial involvement, distant metastases or evidence of Muir-Torre syndrome.