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1.
Clin Infect Dis ; 70(7): 1519-1520, 2020 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-31211838
2.
Clin Infect Dis ; 70(2): 193-199, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-30874791

RESUMEN

BACKGROUND: Cancer patients are at a higher risk for developing influenza (flu)- related complications. It is unclear if the flu vaccine exacerbates immune events in patients treated with immune checkpoint inhibitors (ICIs). METHODS: We conducted an institutional review board-IRB-approved retrospective review of advanced cancer patients on ICIs who received the flu vaccine during three 3 consecutive seasons: 2014-2015, 2015-2016, and 2016-2017. The primary outcome assessed was any "new onset" immune-related adverse event (IRAE). A subset analysis of vaccinated patients newly treated with anti-programmed cell death protein 1 (PD-1) agents (nivolumab or pembrolizumab) was conducted to assess overall IRAE rates for comparison with published clinical trials. RESULTS: During the three 3 seasons, 370 patients met criteria for ICI and vaccination within ~ twoapproximately 2 months (65 days). The most common underlying cancers were lung (46%) and melanoma (19%); 61% of patients received an anti-PD-1 agent only. In the entire cohort, 20% experienced an IRAE (any grade); incidence of grade 3 or 4 toxicity was 8%. No grade 5 events occurred. In the subset of 170 patients newly treated with anti-PD-1 agents, the overall IRAE rate was 18% and, grade 3/4 events occurred in 7.6%. Influenza was diagnosed in 2 patients. CONCLUSIONS: No increase in incidence or severity of IRAEs was detected in patients on ICIs who received the inactivated influenza vaccine within ~ approximately 2 months of ICI. For newly treated patients on anti-PDI-1 agents, IRAE rates were comparable to those from published clinical trials and did not vary with order of administration. Routine seasonal flu vaccination is encouraged in patients on ICIs.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Neoplasias , Humanos , Inhibidores de Puntos de Control Inmunológico , Vacunas contra la Influenza/efectos adversos , Gripe Humana/prevención & control , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Estudios Retrospectivos , Vacunas de Productos Inactivados
4.
Clin Cancer Res ; 23(1): 204-213, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27370605

RESUMEN

PURPOSE: Efforts to discover drugs that overcome resistance to targeted therapies in patients with rare oncogenic alterations, such as NTRK1 and ROS1 rearrangements, are complicated by the cost and protracted timeline of drug discovery. EXPERIMENTAL DESIGN: In an effort to identify inhibitors of NTRK1 and ROS1, which are aberrantly activated in some patients with non-small cell lung cancer (NSCLC), we created and screened a library of existing targeted drugs against Ba/F3 cells transformed with these oncogenes. RESULTS: This screen identified the FDA-approved drug cabozantinib as a potent inhibitor of CD74-ROS1-transformed Ba/F3, including the crizotinib-resistant mutants G2032R and L2026M (IC50 = 9, 26, and 11 nmol/L, respectively). Cabozantinib inhibited CD74-ROS1-transformed Ba/F3 cells more potently than brigatinib (wild-type/G2032R/L2026M IC50 = 30/170/200 nmol/L, respectively), entrectinib (IC50 = 6/2,200/3,500 nmol/L), and PF-06463922 (IC50 = 1/270/2 nmol/L). Cabozantinib inhibited ROS1 autophosphorylation and downstream ERK activation in transformed Ba/F3 cells and in patient-derived tumor cell lines. The IGF-1R inhibitor BMS-536924 potently inhibited CD74-NTRK1-transformed compared with parental Ba/F3 cells (IC50 = 19 nmol/L vs. > 470 nmol/L). A patient with metastatic ROS1-rearranged NSCLC with progression on crizotinib was treated with cabozantinib and experienced a partial response. CONCLUSIONS: While acquired resistance to targeted therapies is challenging, this study highlights that existing agents may be repurposed to overcome drug resistance and identifies cabozantinib as a promising treatment of ROS1-rearranged NSCLC after progression on crizotinib. Clin Cancer Res; 23(1); 204-13. ©2016 AACR.


Asunto(s)
Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Reordenamiento Génico , Neoplasias Pulmonares/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/genética , Receptor trkA/antagonistas & inhibidores , Receptor trkA/genética , Animales , Antineoplásicos/química , Línea Celular Tumoral , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Modelos Moleculares , Conformación Molecular , Terapia Molecular Dirigida , Mutación , Fosforilación , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas/química , Proteínas Tirosina Quinasas Receptoras/química , Receptor trkA/química , Transducción de Señal/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas , Relación Estructura-Actividad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
5.
Tuberculosis (Edinb) ; 101S: S73-S77, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27856197

RESUMEN

Mycobacterium tuberculosis (Mtb) and the Human Immunodeficiency Virus (HIV) pose a major public health threat. The 2015 World Health Organization (WHO) report estimates that one in three HIV deaths is due to Mtb, the causative agent of Tuberculosis (TB). The lethal synergy between these two pathogens leads to a decline in the immune function of infected individuals as well as a rise in morbidity and mortality rates. The deadly interaction between TB and HIV, along with the heightened emergence of drug resistance, drug-drug interactions, reduced drug efficacy and increased drug toxicity, has made the therapeutic management of co-infected individuals a major challenge. Hence, the development of new drug targets and/or new drug leads are imperative for the effective therapeutic management of co-infected patients. Here, we report the characterization of 2-hydroxy-1-naphthaldehyde isonicotinoyl hydrazone (311), a known inhibitor of HIV-1 replication and transcription as a new inhibitor of methionine aminopeptidases (MetAPs) from Mycobacterium tuberculosis: MtMetAP1a and MtMetAP1c. MetAP is a metalloprotease that removes the N-terminal methionine during protein synthesis. The essential role of MetAP in microbes makes it a promising chemotherapeutic target. We demonstrated that 311 is a potent and selective inhibitor of MtMetAP1a and MtMetAP1c. Furthermore, we found that 311 is active against replicating and aged non-growing Mtb at low micromolar concentrations. These results suggest that 311 is a promising lead for the development of novel class of therapeutic agents with dual inhibition of TB and HIV for the treatment of TB-HIV co-infection.


Asunto(s)
Aminopeptidasas/antagonistas & inhibidores , Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , Aminopeptidasas/metabolismo , Fármacos Anti-VIH/farmacología , Proteínas Bacterianas/metabolismo , Coinfección , Relación Dosis-Respuesta a Droga , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Ensayos Analíticos de Alto Rendimiento , Humanos , Isoniazida/farmacología , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/crecimiento & desarrollo , Tuberculosis/microbiología
6.
Cancer Immunol Res ; 4(4): 289-93, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26865455

RESUMEN

The recent approval of two PD-1 inhibitors for the treatment of non-small cell lung cancer (NSCLC) has rapidly led to the widespread use of these agents in oncology practices. Pneumonitis has been recognized as a potentially life-threatening adverse event among NSCLC patients treated with PD-1 inhibitors; however, the detailed clinical and radiographic manifestations of this entity remain to be described. We report on two cases of anti-PD-1 pneumonitis in advanced NSCLC patients treated with nivolumab after its FDA approval. Both patients presented with ground-glass and reticular opacities and consolidations in a peripheral distribution on CT, demonstrating a radiographic pattern of cryptogenic organizing pneumonia. Consolidations were extensive and rapidly developed within 8 weeks of therapy in both cases. Both patients were treated with corticosteroids with subsequent improvement of respiratory symptoms and radiographic findings. One patient experienced recurrent pneumonitis after completing corticosteroid taper, or a "pneumonitis flare," in the absence of nivolumab retreatment, with subsequent improvement upon corticosteroid readministration. With the increasing use of immune checkpoint inhibitors in a growing number of tumor types, awareness of the radiographic and clinical manifestations of PD-1 inhibitor-related pneumonitis will be critical for the prompt diagnosis and management of this potentially serious adverse event.


Asunto(s)
Antineoplásicos/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Neoplasias Pulmonares/complicaciones , Neumonía/etiología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Estadificación de Neoplasias , Nivolumab , Neumonía/diagnóstico , Neumonía/tratamiento farmacológico , Prednisolona/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
7.
Oncotarget ; 6(31): 31018-29, 2015 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-26427042

RESUMEN

The constant presence of the viral genome in Epstein-Barr virus (EBV)-associated gastric cancers (EBVaGCs) suggests the applicability of novel EBV-targeted therapies. The antiviral nucleoside drug, ganciclovir (GCV), is effective only in the context of the viral lytic cycle in the presence of EBV-encoded thymidine kinase (TK)/protein kinase (PK) expression. In this study, screening of the Johns Hopkins Drug Library identified gemcitabine as a candidate for combination treatment with GCV. Pharmacological induction of EBV-TK or PK in EBVaGC-originated tumor cells were used to study combination treatment with GCV in vitro and in vivo. Gemcitabine was found to be a lytic inducer via activation of the ataxia telangiectasia-mutated (ATM)/p53 genotoxic stress pathway in EBVaGC. Using an EBVaGC mouse model and a [125I] fialuridine (FIAU)-based lytic activation imaging system, we evaluated gemcitabine-induced lytic activation in an in vivo system and confirmed the efficacy of gemcitabine-GCV combination treatment. This viral enzyme-targeted anti-tumor strategy may provide a new therapeutic approach for EBVaGCs.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Antivirales/farmacología , Carcinoma/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Infecciones por Virus de Epstein-Barr/tratamiento farmacológico , Ganciclovir/farmacología , Herpesvirus Humano 4/efectos de los fármacos , Terapia Molecular Dirigida , Neoplasias Gástricas/tratamiento farmacológico , Animales , Carcinoma/diagnóstico , Carcinoma/genética , Carcinoma/virología , Línea Celular Tumoral , Desoxicitidina/farmacología , Relación Dosis-Respuesta a Droga , Reposicionamiento de Medicamentos , Inducción Enzimática , Infecciones por Virus de Epstein-Barr/diagnóstico , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/enzimología , Herpesvirus Humano 4/patogenicidad , Humanos , Ratones Endogámicos NOD , Ratones SCID , Proteínas Quinasas/biosíntesis , Interferencia de ARN , Transducción de Señal/efectos de los fármacos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/virología , Timidina Quinasa/biosíntesis , Factores de Tiempo , Transfección , Carga Tumoral/efectos de los fármacos , Proteínas Virales/biosíntesis , Activación Viral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Gemcitabina
8.
Lung Cancer ; 86(2): 241-6, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25218177

RESUMEN

OBJECTIVES: The optimal management of locally advanced and metastatic pulmonary carcinoid tumors remains to be determined. MATERIALS AND METHODS: A retrospective review was conducted on patients with typical and atypical pulmonary carcinoid tumors treated at our institutions between 1990 and 2012. RESULTS: 300 patients were identified with pulmonary carcinoid, (80 patients with atypical carcinoid), of whom 29 presented with metastatic disease (16 atypical). Of evaluable patients, 26 (41%) with stages I-III atypical carcinoid tumors recurred at a median time of 3.7 years (range, 0.4-32), compared to 3 (1%) patients with typical carcinoid (range, 8-12.3). 39 patients were treated with chemotherapy, including 30 patients with metastatic disease (27 atypical), and 7 patients were treated with adjuvant platinum-etoposide chemoradiation (6 atypical, 1 typical, 6 stage IIIA, 1 stage IIB). At a median follow-up of 2 years there were 2 recurrences in the 7 patients receiving adjuvant treatment. Median survival after diagnosis of metastatic disease for patients with atypical pulmonary carcinoid was 3.3 years with a 5-year survival of 24%. Treatment regimens showing efficacy in pulmonary carcinoid include 15 patients treated with octreotide-based therapies (10% response rate (RR), 70% disease control rate (DCR), 15 month median progression-free survival (PFS)), 13 patients treated with etoposide+platinum (23% RR, 69% DCR, 7 month median PFS), and 14 patients treated with temozolomide-based therapies (14% RR, 57% DCR, 10 month median PFS). 8 of 10 patients with octreotide-avid disease treated with an octreotide-based regimen experienced disease control (1 partial response, 7 stable disease) for a median of 18 months (range 6-72 months). CONCLUSIONS: These results support our previous finding that a subset of pulmonary carcinoid tumors are responsive to chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Tumor Carcinoide/tratamiento farmacológico , Tumor Carcinoide/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Adulto , Anciano , Anciano de 80 o más Años , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/mortalidad , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
9.
Nat Med ; 19(11): 1389-400, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24202392

RESUMEN

All patients with metastatic lung, colorectal, pancreatic or head and neck cancers who initially benefit from epidermal growth factor receptor (EGFR)-targeted therapies eventually develop resistance. An increasing understanding of the number and complexity of resistance mechanisms highlights the Herculean challenge of killing tumors that are resistant to EGFR inhibitors. Our growing knowledge of resistance pathways provides an opportunity to develop new mechanism-based inhibitors and combination therapies to prevent or overcome therapeutic resistance in tumors. We present a comprehensive review of resistance pathways to EGFR-targeted therapies in lung, colorectal and head and neck cancers and discuss therapeutic strategies that are designed to circumvent resistance.


Asunto(s)
Receptores ErbB/antagonistas & inhibidores , Terapia Molecular Dirigida/tendencias , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Resistencia a Antineoplásicos/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Modelos Biológicos , Mutación , Neoplasias/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Transducción de Señal
10.
Cancer Discov ; 1(1): 68-77, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22140654

RESUMEN

UNLABELLED: Identification of novel indications for commonly prescribed drugs could accelerate translation of therapies. We investigated whether any clinically-used drugs might have utility for treating prostate cancer by coupling an efficient, high-throughput laboratory-based screen and a large, prospective cohort study. In stage 1, we conducted an in vitro prostate cancer cell cytotoxicity screen of 3,187 compounds. Digoxin emerged as the leading candidate given its potency in inhibiting proliferation in vitro (mean IC50=163 nM) and common use. In stage 2, we evaluated the association between the leading candidate drug from stage 1 and prostate cancer risk in 47,884 men followed 1986-2006. Regular digoxin users (versus nonusers: RR=0.76, 95% CI 0.61-0.95), especially users for ≥ 10 years (RR=0.54, 95% CI 0.37-0.79, P-trend<0.001), had a lower prostate cancer risk. Digoxin was highly potent in inhibiting prostate cancer cell growth in vitro and its use was associated with a 25% lower prostate cancer risk. SIGNIFICANCE: Our two-stage transdisciplinary approach for drug repositioning provides compelling justification for further mechanistic and possibly clinical testing of the leading nonchemotherapy candidate, digoxin, a cardiac glycoside, as a drug for prostate cancer treatment. Perhaps of equal importance, our study illustrates the power of the transdisciplinary approach in translational cancer research. By coupling laboratory and epidemiologic methods and thinking, we reduced the probability of identifying false-positive candidate drugs for the next steps in testing.


Asunto(s)
Digoxina/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Neoplasias de la Próstata/patología , Factores de Riesgo , Encuestas y Cuestionarios
11.
J Natl Cancer Inst ; 102(24): 1855-73, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-21088277

RESUMEN

BACKGROUND: Angiogenesis plays an important role in tumor growth and metastasis; therefore, inhibition of angiogenesis is a promising strategy for developing new anticancer drugs. Type 2 methionine aminopeptidase (MetAP2) protein is likely a molecular target of angiogenesis inhibitors. METHODS: Nitroxoline, an antibiotic used to treat urinary tract infections, was identified from a high-throughput screen of a library of 175,000 compounds for MetAP2 inhibitors and from a parallel screen using the Johns Hopkins Drug Library to identify currently used clinical drugs that can also inhibit human umbilical vein endothelial cells (HUVEC) proliferation. To investigate the mechanism of action of nitroxoline, inhibition of MetAP2 activity and induction of senescence were assessed in HUVEC. To test the antiangiogenic activity of nitroxoline, endothelial tube formation in Matrigel and microvessel formation in Matrigel plugs in vivo were assessed. Antitumor efficacy of nitroxoline was evaluated in mouse models of human breast cancer xenograft (n = 10) and bladder cancer orthotopic xenograft (n = 11). Furthermore, the mechanism of action of nitroxoline was investigated in vivo. RESULTS: Nitroxoline inhibited MetAP2 activity in vitro (half maximal inhibitory concentration [IC(50)] = 54.8 nM, 95% confidence interval [CI] = 22.6 to 132.8 nM) and HUVEC proliferation (IC(50) = 1.9 µM, 95% CI = 1.54 to 2.39 µM). Nitroxoline inhibited MetAP2 activity in HUVEC in a dose-dependent manner and induced premature senescence in a biphasic manner. Nitroxoline inhibited endothelial tube formation in Matrigel and reduced microvessel density in vivo. Mice (five per group) treated with nitroxoline showed a 60% reduction in tumor volume in breast cancer xenografts (tumor volume on day 30, vehicle vs nitroxoline, mean = 215.4 vs 86.5 mm(3), difference = 128.9 mm(3), 95% CI = 32.9 to 225.0 mm(3), P = .012) and statistically significantly inhibited growth of bladder cancer in an orthotopic mouse model (tumor bioluminescence intensities of vehicle [n = 5] vs nitroxoline [n = 6], P = .045). CONCLUSION: Nitroxoline shows promise as a potential therapeutic antiangiogenic agent.


Asunto(s)
Aminopeptidasas/antagonistas & inhibidores , Inhibidores de la Angiogénesis/farmacología , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/tratamiento farmacológico , Glicoproteínas/antagonistas & inhibidores , Neovascularización Patológica/prevención & control , Nitroquinolinas/farmacología , Sirtuina 1/antagonistas & inhibidores , Neoplasias de la Vejiga Urinaria/irrigación sanguínea , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Acetilación/efectos de los fármacos , Aminopeptidasas/metabolismo , Animales , Antiinfecciosos Urinarios/farmacología , Proliferación Celular/efectos de los fármacos , Colágeno , Ciclohexanos/farmacología , Modelos Animales de Enfermedad , Combinación de Medicamentos , Sinergismo Farmacológico , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Femenino , Glicoproteínas/metabolismo , Humanos , Immunoblotting , Inmunohistoquímica , Laminina , Metionil Aminopeptidasas , Ratones , Ratones Desnudos , O-(Cloroacetilcarbamoil) Fumagilol , Proteoglicanos , ARN Interferente Pequeño , Proteínas Recombinantes , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sesquiterpenos/farmacología , Sirtuina 1/metabolismo , Transfección , Venas Umbilicales/metabolismo , Venas Umbilicales/patología , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Cancer Cell ; 17(4): 388-99, 2010 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-20385363

RESUMEN

In a screen of drugs previously tested in humans we identified itraconazole, a systemic antifungal, as a potent antagonist of the Hedgehog (Hh) signaling pathway that acts by a mechanism distinct from its inhibitory effect on fungal sterol biosynthesis. Systemically administered itraconazole, like other Hh pathway antagonists, can suppress Hh pathway activity and the growth of medulloblastoma in a mouse allograft model and does so at serum levels comparable to those in patients undergoing antifungal therapy. Mechanistically, itraconazole appears to act on the essential Hh pathway component Smoothened (SMO) by a mechanism distinct from that of cyclopamine and other known SMO antagonists, and prevents the ciliary accumulation of SMO normally caused by Hh stimulation.


Asunto(s)
Antineoplásicos/uso terapéutico , Proteínas Hedgehog/antagonistas & inhibidores , Itraconazol/uso terapéutico , Transducción de Señal/efectos de los fármacos , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Carcinoma Basocelular/tratamiento farmacológico , División Celular/efectos de los fármacos , Ciclodextrinas/farmacología , Proteínas Hedgehog/química , Proteínas Hedgehog/efectos de los fármacos , Proteínas Hedgehog/fisiología , Humanos , Itraconazol/farmacología , Cinética , Lipoproteínas LDL/fisiología , Ratones , Modelos Moleculares
15.
PLoS One ; 3(12): e4009, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19104661

RESUMEN

The Kv1.3 potassium channel plays an essential role in effector memory T cells and has been implicated in several important autoimmune diseases including multiple sclerosis, psoriasis and type 1 diabetes. A number of potent small molecule inhibitors of Kv1.3 channel have been reported, some of which were found to be effective in various animal models of autoimmune diseases. We report herein the identification of clofazimine, a known anti-mycobacterial drug, as a novel inhibitor of human Kv1.3. Clofazimine was initially identified as an inhibitor of intracellular T cell receptor-mediated signaling leading to the transcriptional activation of human interleukin-2 gene in T cells from a screen of the Johns Hopkins Drug Library. A systematic mechanistic deconvolution revealed that clofazimine selectively blocked the Kv1.3 channel activity, perturbing the oscillation frequency of the calcium-release activated calcium channel, which in turn led to the inhibition of the calcineurin-NFAT signaling pathway. These effects of clofazimine provide the first line of experimental evidence in support of a causal relationship between Kv1.3 and calcium oscillation in human T cells. Furthermore, clofazimine was found to be effective in blocking human T cell-mediated skin graft rejection in an animal model in vivo. Together, these results suggest that clofazimine is a promising immunomodulatory drug candidate for treating a variety of autoimmune disorders.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Clofazimina/farmacología , Canal de Potasio Kv1.3/antagonistas & inhibidores , Linfocitos T/efectos de los fármacos , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Señalización del Calcio/inmunología , Células Cultivadas , Clofazimina/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Factores Inmunológicos/metabolismo , Factores Inmunológicos/farmacología , Interleucina-2/metabolismo , Células Jurkat , Canal de Potasio Kv1.3/genética , Canal de Potasio Kv1.3/metabolismo , Ratones , Modelos Biológicos , Factores de Transcripción NFATC/metabolismo , Unión Proteica , Multimerización de Proteína/efectos de los fármacos , Trasplante de Piel/inmunología , Linfocitos T/metabolismo , Transfección
16.
Antimicrob Agents Chemother ; 52(9): 3106-12, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18591280

RESUMEN

No effective approved drug therapy exists for Cryptosporidium infection of immunocompromised patients. Here we investigated the nonabsorbed anthelmintic drug pyrvinium pamoate for inhibition of the growth of the intestinal protozoan parasite Cryptosporidium parvum. The concentration of pyrvinium that effected 50% growth inhibition in human enterocytic HCT-8 cells by a quantitative alkaline phosphatase immunoassay was 354 nM. For comparison, in the same assay, 50% growth inhibition was obtained with 711 microM paromomycin or 27 microM chloroquine. We used a neonatal mouse model to measure the anti-Cryptosporidium activity of pyrvinium pamoate in vivo. Beginning 3 days after infection, pyrvinium at 5 or 12.5 mg/kg of body weight/day was administered to the treatment group mice for 4 or 6 consecutive days. Nine days after infection, the mice were sacrificed, and drug efficacy was determined by comparing the numbers of oocysts in the fecal smears of treated versus untreated mice. The intensities of trophozoite infection in the ileocecal intestinal regions were also compared using hematoxylin-and-eosin-stained histological slides. We observed a >90% reduction in infection intensity in pyrvinium-treated mice relative to that in untreated controls, along with a substantial reduction in tissue pathology. Based on these results, pyrvinium pamoate is a potential drug candidate for the treatment of cryptosporidiosis in both immunocompetent and immunocompromised individuals.


Asunto(s)
Antiprotozoarios/uso terapéutico , Criptosporidiosis/tratamiento farmacológico , Cryptosporidium parvum/efectos de los fármacos , Modelos Animales de Enfermedad , Compuestos de Pirvinio/uso terapéutico , Animales , Animales Recién Nacidos , Antiprotozoarios/farmacología , Línea Celular , Criptosporidiosis/parasitología , Cryptosporidium parvum/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Ratones Endogámicos BALB C , Compuestos de Pirvinio/farmacología , Resultado del Tratamiento
17.
Pediatr Dev Pathol ; 11(5): 405-15, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17990935

RESUMEN

Idiopathic infantile arterial calcification (IIAC) is a rare disorder characterized by extensive calcification of medium and large arteries. We report the case of a 32-week-old infant with hydrops fetalis and heart failure who died at 4 days of age. At autopsy the infant was found to have cardiomegaly, myocardial infarctions and multifocal calcifications of the aorta and arteries in the lungs, heart, thyroid, spleen, and testis. Calcification extended from the internal elastic lamina into the intima and media and was associated with a giant-cell reaction and smooth muscle proliferation. A search of the English language medical literature identified 161 IIAC case reports. Of these, 48% of cases presented in utero or at birth with hydrops fetalis, maternal hydramnios, heart failure, or respiratory distress and 52% present later, at a median age of 3 months, with sudden onset of fever, vomiting, irritability, or respiratory distress in a previously healthy infant. Significantly, 19 of 22 IIAC survivors presented at less than 2 weeks of age, and 15 survivors were treated with diphosphonates.


Asunto(s)
Arterias/diagnóstico por imagen , Calcinosis , Enfermedades Vasculares , Calcinosis/complicaciones , Calcinosis/diagnóstico por imagen , Cardiomegalia/patología , Resultado Fatal , Insuficiencia Cardíaca/patología , Humanos , Hidropesía Fetal/diagnóstico por imagen , Recién Nacido , Masculino , Infarto del Miocardio/patología , Radiografía , Ultrasonografía , Enfermedades Vasculares/complicaciones , Enfermedades Vasculares/diagnóstico por imagen
18.
J Med Chem ; 50(22): 5524-7, 2007 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-17918925

RESUMEN

The antiarthritis drug D-penicillamine (D-PEN) catalyzes zinc(II) transfer from carboxypeptidase A to chelators such as thionein and EDTA at a rate constant up to 400-fold faster than the uncatalyzed release. Once D-PEN releases zinc(II) from enzyme stronger chelators can tightly bind zinc(II) leading to complete and essentially irreversible inhibition. D-PEN is the first drug to inhibit a zinc protease by catalyzing metal removal, and the name "catalytic chelation" is proposed for this mechanism.


Asunto(s)
Carboxipeptidasas A/antagonistas & inhibidores , Quelantes/química , Ácido Edético/química , Ergotioneína/química , Penicilamina/química , Zinc/química , Animales , Carboxipeptidasas A/química , Catálisis , Bovinos , Sinergismo Farmacológico , Cinética
20.
N Engl J Med ; 356(25): 2614-21, 2007 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-17582071

RESUMEN

Entecavir, a drug approved by the Food and Drug Administration for the treatment of chronic hepatitis B virus (HBV) infection, is not believed to inhibit replication of human immunodeficiency virus type 1 (HIV-1) at clinically relevant doses. We observed that entecavir led to a consistent 1-log(10) decrease in HIV-1 RNA in three persons with HIV-1 and HBV coinfection, and we obtained supportive in vitro evidence that entecavir is a potent partial inhibitor of HIV-1 replication. Detailed analysis showed that in one of these patients, entecavir monotherapy led to an accumulation of HIV-1 variants with the lamivudine-resistant mutation, M184V. In vitro experiments showed that M184V confers resistance to entecavir. Until more is known about HIV-1-resistance patterns and their selection by entecavir, caution is needed with the use of entecavir in persons with HIV-1 and HBV coinfection who are not receiving fully suppressive antiretroviral regimens.


Asunto(s)
Antivirales/farmacología , Guanina/análogos & derivados , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Hepatitis B/tratamiento farmacológico , Inhibidores de la Transcriptasa Inversa/farmacología , Replicación Viral/efectos de los fármacos , Adulto , Antivirales/uso terapéutico , Recuento de Linfocito CD4 , Farmacorresistencia Viral , Guanina/farmacología , Guanina/uso terapéutico , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , Transcriptasa Inversa del VIH/genética , VIH-1/genética , VIH-1/fisiología , Hepatitis B/complicaciones , Virus de la Hepatitis B , Humanos , Lamivudine/uso terapéutico , Masculino , Persona de Mediana Edad , Mutación , Filogenia , ARN Viral/sangre , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Transcripción Reversa/efectos de los fármacos , Zidovudina/uso terapéutico
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