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1.
Int J Obes (Lond) ; 46(12): 2128-2136, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36167764

RESUMEN

BACKGROUND AND OBJECTIVES: A2A adenosine receptor (A2AAR)-mediated signaling in adipose tissues has been investigated as a potential target for obesity-related metabolic diseases. LJ-4378 has been developed as a dual-acting ligand with A2AAR agonist and A3 adenosine receptor (A3AR) antagonist activity. The current study aimed to investigate the anti-obesity effects of LJ-4378 and its underlying molecular mechanisms. METHODS: Immortalized brown adipocytes were used for in vitro analysis. A high-fat diet (HFD)-induced obesity and cell death-inducing DFFA-like effector A reporter mouse models were used for in vivo experiments. The effects of LJ-4378 on lipolysis and mitochondrial metabolism were evaluated using immunoblotting, mitochondrial staining, and oxygen consumption rate analyses. The in vivo anti-obesity effects of LJ-4378 were evaluated using indirect calorimetry, body composition analyses, glucose tolerance tests, and histochemical analyses. RESULTS: In vitro LJ-4378 treatment increased the levels of brown adipocyte markers and mitochondrial proteins, including uncoupling protein 1. The effects of LJ-4378 on lipolysis of adipocytes were more potent than those of the A2AAR agonist or A3AR antagonist. In vivo, LJ-4378 treatment increased energy expenditure by 17.0% (P value < 0.0001) compared to vehicle controls. LJ-4378 (1 mg/kg, i.p.) treatment for 10 days reduced body weight and fat content by 8.24% (P value < 0.0001) and 24.2% (P value = 0.0044), respectively, and improved glucose tolerance in the HFD-fed mice. LJ-4378 increased the expression levels of brown adipocyte markers and mitochondrial proteins in interscapular brown and inguinal white adipose tissue. CONCLUSION: These findings support the in vivo anti-obesity effects of LJ-4378, and suggest a novel therapeutic approach to combat obesity and related metabolic diseases.


Asunto(s)
Adenosina , Enfermedades Metabólicas , Animales , Ratones , Adenosina/metabolismo , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Dieta Alta en Grasa , Ligandos , Enfermedades Metabólicas/metabolismo , Ratones Endogámicos C57BL , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Proteína Desacopladora 1/metabolismo , Receptores Purinérgicos P1/metabolismo
2.
Microb Pathog ; 168: 105605, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35636692

RESUMEN

The global spread of H5N1 highly pathogenic avian influenza virus (HPAIV) in poultry has caused great economic loss to the poultry farmers and industry with significant pandemic threat. The current study involved production of recombinant HA1 protein of clade 2.3.2.1a H5N1 HPAIV (rH5HA1) in E.coli and evaluation of its protective efficacy in chickens. Purification under denaturing conditions and refolding by dialysis against buffers containing decreasing concentrations of urea was found to preserve the biological activity of the expressed recombinant protein as assessed by hemagglutination assay, Western blot and ELISA. The Montanide ISA 71 VGA adjuvanted rH5HA1 protein was used for immunization of chickens. Humoral response was maintained at a minimum of 4log2 hemagglutination inhibition (HI) titre till 154 days post 2nd booster. We evaluated the protective efficacy of rH5HA1 protein in immunized chickens by challenging them with homologous (2.3.2.1a) and heterologous (2.3.2.1c) clades of H5N1 HPAIV. In both the groups, the HI titre significantly increased (P < 0.05) after challenge and the virus shedding significantly (P < 0.05) reduced between 3rd and 14th day post challenge. The virus shedding ratio in oro-pharyngeal swabs did not differ significantly between both the groups except on 7 days post challenge and during the entire experimental period in cloacal swabs. These results indicate that rH5HA1 was able to induce homologous and cross protective immune response in chickens and could be a potential vaccine candidate used for combating the global spread of H5N1 HPAIV threat. To our knowledge, this is the first study to report immunogenicity and protective efficacy of prokaryotic recombinant H5HA1 protein in chicken.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Aviar , Animales , Pollos , Escherichia coli/genética , Subtipo H5N1 del Virus de la Influenza A/genética , Vacunas contra la Influenza/genética , Aceite Mineral , Proteínas Recombinantes/genética , Diálisis Renal
4.
Clin Cancer Res ; 28(1): 227-237, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34667030

RESUMEN

PURPOSE: Mutations in STK11 (LKB1) occur in 17% of lung adenocarcinoma (LUAD) and drive a suppressive (cold) tumor immune microenvironment (TIME) and resistance to immunotherapy. The mechanisms underpinning the establishment and maintenance of a cold TIME in LKB1-mutant LUAD remain poorly understood. In this study, we investigated the role of the LKB1 substrate AMPK in immune evasion in human non-small cell lung cancer (NSCLC) and mouse models and explored the mechanisms involved. EXPERIMENTAL DESIGN: We addressed the role of AMPK in immune evasion in NSCLC by correlating AMPK phosphorylation and immune-suppressive signatures and by deleting AMPKα1 (Prkaa1) and AMPKα2 (Prkaa2) in a KrasG12D -driven LUAD. Furthermore, we dissected the molecular mechanisms involved in immune evasion by comparing gene-expression signatures, AMPK activity, and immune infiltration in mouse and human LUAD and gain or loss-of-function experiments with LKB1- or AMPK-deficient cell lines. RESULTS: Inactivation of both AMPKα1 and AMPKα2 together with Kras activation accelerated tumorigenesis and led to tumors with reduced infiltration of CD8+/CD4+ T cells and gene signatures associated with a suppressive TIME. These signatures recapitulate those in Lkb1-deleted murine LUAD and in LKB1-deficient human NSCLC. Interestingly, a similar signature is noted in human NSCLC with low AMPK activity. In mechanistic studies, we find that compromised LKB1 and AMPK activity leads to attenuated antigen presentation in both LUAD mouse models and human NSCLC. CONCLUSIONS: The results provide evidence that the immune evasion noted in LKB1-inactivated lung cancer is due to subsequent inactivation of AMPK and attenuation of antigen presentation.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Adenocarcinoma del Pulmón/genética , Animales , Presentación de Antígeno , Carcinoma de Pulmón de Células no Pequeñas/genética , Humanos , Evasión Inmune , Neoplasias Pulmonares/patología , Ratones , Microambiente Tumoral
5.
Pharmaceuticals (Basel) ; 14(12)2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34959689

RESUMEN

The development of anticancer drugs remains challenging owing to the potential for drug resistance. The simultaneous inhibition of multiple targets involved in cancer could overcome resistance, and these agents would exhibit higher potency than single-target inhibitors. Protein kinases represent a promising target for the development of anticancer agents. As most multi-kinase inhibitors are heterocycles occupying only the hinge and hydrophobic region in the ATP binding site, we aimed to design multi-kinase inhibitors that would occupy the ribose pocket, along with the hinge and hydrophobic region, based on ATP-kinase interactions. Herein, we report the discovery of a novel 4'-thionucleoside template as a multi-kinase inhibitor with potent anticancer activity. The in vitro evaluation revealed a lead 1g (7-acetylene-7-deaza-4'-thioadenosine) with potent anticancer activity, and marked inhibition of TRKA, CK1δ, and DYRK1A/1B kinases in the kinome scan assay. We believe that these findings will pave the way for developing anticancer drugs.

6.
Int J Mol Sci ; 22(11)2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-34073488

RESUMEN

Kidney fibrosis is the final outcome of chronic kidney disease (CKD). Adenosine plays a significant role in protection against cellular damage by activating four subtypes of adenosine receptors (ARs), A1AR, A2AAR, A2BAR, and A3AR. A2AAR agonists protect against inflammation, and A3AR antagonists effectively inhibit the formation of fibrosis. Here, we showed for the first time that LJ-4459, a newly synthesized dual-acting ligand that is an A2AAR agonist and an A3AR antagonist, prevents the progression of tubulointerstitial fibrosis. Unilateral ureteral obstruction (UUO) surgery was performed on 6-week-old male C57BL/6 mice. LJ-4459 (1 and 10 mg/kg) was orally administered for 7 days, started at 1 day before UUO surgery. Pretreatment with LJ-4459 improved kidney morphology and prevented the progression of tubular injury as shown by decreases in urinary kidney injury molecular-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) excretion. Obstruction-induced tubulointerstitial fibrosis was attenuated by LJ-4459, as shown by a decrease in fibrotic protein expression in the kidney. LJ-4459 also inhibited inflammation and oxidative stress in the obstructed kidney, with reduced macrophage infiltration, reduced levels of pro-inflammatory cytokines, as well as reduced levels of reactive oxygen species (ROS). These data demonstrate that LJ-4459 has potential as a therapeutic agent against the progression of tubulointerstitial fibrosis.


Asunto(s)
Agonistas del Receptor de Adenosina A3/farmacología , Enfermedades Renales/tratamiento farmacológico , Receptor de Adenosina A2A/metabolismo , Receptor de Adenosina A3/metabolismo , Obstrucción Ureteral/tratamiento farmacológico , Agonistas del Receptor de Adenosina A3/síntesis química , Agonistas del Receptor de Adenosina A3/química , Animales , Fibrosis , Enfermedades Renales/etiología , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Ligandos , Masculino , Ratones , Obstrucción Ureteral/complicaciones , Obstrucción Ureteral/metabolismo , Obstrucción Ureteral/patología
7.
Can J Urol ; 28(2): 10596-10602, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33872557

RESUMEN

INTRODUCTION Accurate staging of urothelial bladder cancer (UBC) with imaging, which guides effective bladder cancer treatment, remains challenging. This investigation is to validate a hypothesis that targeting Vasoactive intestinal and pituitary adenylate cyclase activating peptide (VPAC) receptors using 64Cu-TP3805 can PET image UBC efficiently. MATERIALS AND METHODS: Nineteen patients (44-84 years of age) scheduled for radical cystectomy, underwent VPAC positron emission tomography (PET) imaging prior to surgery. Sixteen had completed neoadjuvant chemotherapy prior to imaging. All 19 received 64Cu-TP3805 (148 % ± 10% MBq) intravenously, and were imaged 60 to 90 minutes later. Standard uptake value (SUV)max for malignant lesions and SUVmean for normal tissues were determined and mean +/-SEM recorded. Following radical cystoprostatectomy, pelvic lymphadenectomy and urinary diversion imaging, results were compared with final surgical pathology. RESULTS: 64Cu-TP3805 had no adverse events, negligible urinary excretion and rapid blood clearance. UBC PET images for residual disease were true positive in 11 patients and true negative in four. Of remaining 4, one had false positive and 3 had false negative scans, equating to 79% sensitivity (95%, CI 49%-95%), 80% specificity (95%, CI 28%-100%), 92% positive predictive value (95%, CI 62%-100%) and 57% negative predictive value (95%, CI 18%-90%). CONCLUSIONS: These first in man results, in a group, heavily pretreated with neoadjuvant chemotherapy, indicate that VPAC PET imaging can identify UBC effeiciently and suggest, that VPAC PET can diagnose UBC in a treatment naïve cohort for accurate staging, guide biopsy and treatment in patients with suspected metastasis and determine response to therapy. Further investigation of this molecular imaging approach is warranted.


Asunto(s)
Carcinoma de Células Transicionales/diagnóstico por imagen , Complejos de Coordinación , Péptidos , Tomografía Computarizada por Rayos X/métodos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/cirugía , Cistectomía , Humanos , Persona de Mediana Edad , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Neoplasias de la Vejiga Urinaria/cirugía , Péptido Intestinal Vasoactivo
8.
Gastroenterology ; 158(5): 1389-1401.e10, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31930988

RESUMEN

BACKGROUND & AIMS: In addition to the Notch and Wnt signaling pathways, energy metabolism also regulates intestinal stem cell (ISC) function. Tumor suppressor and kinase STK11 (also called LKB1) regulates stem cells and cell metabolism. We investigated whether loss of LKB1 alters ISC homeostasis in mice. METHODS: We deleted LKB1 from ISCs in mice using Lgr5-regulated CRE-ERT2 (Lkb1Lgr5-KO mice) and the traced lineages by using a CRE-dependent TdTomato reporter. Intestinal tissues were collected and analyzed by immunohistochemical and immunofluorescence analyses. We purified ISCs and intestinal progenitors using flow cytometry and performed RNA-sequencing analysis. We measured organoid-forming capacity and ISC percentages using intestinal tissues from Lkb1Lgr5-KO mice. We analyzed human Ls174t cells with knockdown of LKB1 or other proteins by immunoblotting, real-time quantitative polymerase chain reaction, and the Seahorse live-cell metabolic assay. RESULTS: Some intestinal crypts from Lkb1Lgr5-KO mice lost ISCs compared with crypts from control mice. However, most crypts from Lkb1Lgr5-KO mice contained functional ISCs that expressed increased levels of Atoh1 messenger RNA (mRNA), acquired a gene expression signature associated with secretory cells, and generated more cells in the secretory lineage compared with control mice. Knockdown of LKB1 in Ls174t cells induced expression of Atoh1 mRNA and a phenotype of increased mucin production; knockdown of ATOH1 prevented induction of this phenotype. The increased expression of Atoh1 mRNA after LKB1 loss from ISCs or Ls174t cells did not involve Notch or Wnt signaling. Knockdown of pyruvate dehydrogenase kinase 4 (PDK4) or inhibition with dichloroacetate reduced the up-regulation of Atoh1 mRNA after LKB1 knockdown in Ls174t cells. Cells with LKB1 knockdown had a reduced rate of oxygen consumption, which was partially restored by PDK4 inhibition with dichloroacetate. ISCs with knockout of LKB1 increased the expression of PDK4 and had an altered metabolic profile. CONCLUSIONS: LKB1 represses transcription of ATOH1, via PDK4, in ISCs, restricting their differentiation into secretory lineages. These findings provide a connection between metabolism and the fate determination of ISCs.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Metabolismo Energético/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Células Madre/fisiología , Quinasas de la Proteína-Quinasa Activada por el AMP , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Línea Celular Tumoral , Ácido Dicloroacético/farmacología , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Mucosa Intestinal/citología , Intestino Delgado/citología , Ratones , Ratones Noqueados , Cultivo Primario de Células , Proteínas Serina-Treonina Quinasas/genética , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/antagonistas & inhibidores , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , RNA-Seq , Transcripción Genética , Regulación hacia Arriba/efectos de los fármacos
9.
Mol Imaging Biol ; 22(2): 293-302, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31292914

RESUMEN

PURPOSE: Scintigraphic imaging of malignant glioblastoma (MG) continues to be challenging. We hypothesized that VPAC1 cell surface receptors can be targeted for positron emission tomography (PET) imaging of orthotopically implanted MG in a mouse model, using a VPAC1-specific peptide [64Cu]TP3805. PROCEDURES: The expression of VPAC1 in mouse GL261 and human U87 glioma cell lines was determined by western blot. The ability of [64Cu]TP3805 to bind to GL261 and U87 cells was studied by cell-binding. Receptor-blocking studies were performed to validate receptor specificity. GL261 tumors were implanted orthotopically in syngeneic T-bet knockout C57BL/6 mouse brain (N = 15) and allowed to grow for 2-3 weeks. Mice were injected i.v., first with ~ 150 µCi of 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) then 24 h later with ~ 200 µCi of [64Cu]TP3805. In another set of tumor-bearing mice, (N = 5), ionic [64Cu]Cl2 was injected as a control. Mice were imaged at a 2-h post-injection using an Inveon micro-PET/CT, sacrificed and % ID/g of [64Cu]TP3805 and [64Cu]Cl2 were calculated in a tumor, normal brain, and other tissues. For histologic tissue examination, 3-µm thick sections of the tumors and normal brain were prepared, digital autoradiography (DAR) was performed, and then the sections were H&E stained for histologic examination. RESULTS: Western blots showed a strong signal for VPAC1 on both cell lines. [64Cu]TP3805 cell-binding was 87 ± 1.5 %. Receptor-blocking reduced cell-binding to 24.3 ± 1.5 % (P < 0.01). PET imaging revealed remarkable accumulation of [64Cu]TP3805 in GL261 MG with a negligible background in the normal brain, as compared to [18F]FDG. Micro-PET/CT image analyses and tissue distribution showed that the brain tumor uptake for [64Cu]TP3805 was 8.2 ± 1.7 % ID/g and for [64Cu]Cl2 2.1 ± 0.5 % ID/g as compared to 1.0 ± 0.3 % ID/g and 1.4 ± 0.3 % ID/g for normal mouse brains, respectively. The high tumor/normal brain ratio for [64Cu]TP3805 (8.1 ± 1.1) allowed tumors to be visualized unequivocally. Histology and [64Cu]TP3805 DAR differentiated malignant tumors from healthy brain and confirmed PET findings. CONCLUSION: Targeting VPAC1 receptors using [64Cu]TP3805 for PET imaging of MG is a promising novel approach and calls for further investigation.


Asunto(s)
Radioisótopos de Cobre/farmacología , Glioblastoma/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Receptores de Tipo I del Polipéptido Intestinal Vasoactivo/genética , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Neoplasias Encefálicas/diagnóstico por imagen , Línea Celular Tumoral , Fluorodesoxiglucosa F18 , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Trasplante de Neoplasias , Péptidos/química , Radiofármacos , Distribución Tisular
10.
Matrix Biol ; 77: 41-57, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30098419

RESUMEN

The αvß3 integrin has been shown to promote aggressive phenotypes in many types of cancers, including prostate cancer. We show that GFP-labeled αvß3 derived from cancer cells circulates in the blood and is detected in distant lesions in NOD scid gamma (NSG) mice. We, therefore, hypothesized that αvß3 travels through exosomes and tested its levels in pools of vesicles, which we designate extracellular vesicles highly enriched in exosomes (ExVs), and in exosomes isolated from the plasma of prostate cancer patients. Here, we show that the αvß3 integrin is found in patient blood exosomes purified by sucrose or iodixanol density gradients. In addition, we provide evidence that the αvß3 integrin is transferred through ExVs isolated from prostate cancer patient plasma to ß3-negative recipient cells. We also demonstrate the intracellular localization of ß3-GFP transferred via cancer cell-derived ExVs. We show that the ExVs present in plasma from prostate cancer patients contain higher levels of αvß3 and CD9 as compared to plasma ExVs from age-matched subjects who are not affected by cancer. Furthermore, using PSMA antibody-bead mediated immunocapture, we show that the αvß3 integrin is expressed in a subset of exosomes characterized by PSMA, CD9, CD63, and an epithelial-specific marker, Trop-2. Finally, we present evidence that the levels of αvß3, CD63, and CD9 remain unaltered in ExVs isolated from the blood of prostate cancer patients treated with enzalutamide. Our results suggest that detecting exosomal αvß3 integrin in prostate cancer patients could be a clinically useful and non-invasive biomarker to follow prostate cancer progression. Moreover, the ability of αvß3 integrin to be transferred from ExVs to recipient cells provides a strong rationale for further investigating the role of αvß3 integrin in the pathogenesis of prostate cancer and as a potential therapeutic target.


Asunto(s)
Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Exosomas/metabolismo , Integrina alfaVbeta3/genética , Neoplasias de la Próstata/genética , Adenocarcinoma/sangre , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antineoplásicos/farmacología , Benzamidas , Biomarcadores de Tumor/sangre , Exosomas/química , Expresión Génica , Humanos , Integrina alfaVbeta3/sangre , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Nitrilos , Células PC-3 , Feniltiohidantoína/análogos & derivados , Feniltiohidantoína/farmacología , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Tetraspanina 29/sangre , Tetraspanina 29/genética , Tetraspanina 30/sangre , Tetraspanina 30/genética , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Mol Imaging Biol ; 21(1): 130-139, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29802552

RESUMEN

PURPOSE: In recent years, considerable progress has been made in the use of gallium-68 labeled receptor-specific peptides for imaging oncologic diseases. The objective was to examine the stability and pharmacokinetics of [68Ga]NODAGA and DOTA-peptide conjugate targeting VPAC [combined for vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP)] receptors on tumor cells. PROCEDURES: A VPAC receptor-specific peptide was chosen as a model peptide and conjugated to NODAGA and DOTA via solid-phase synthesis. The conjugates were characterized by HPLC and MALDI-TOF. Following Ga-68 chelation, the radiochemical purity of Ga-68 labeled peptide conjugate was determined by radio-HPLC. The stability was tested against transmetallation using 100 nM Fe3+/Zn2+/Ca2+ ionic solution and against transchelation using 200 µM DTPA solution. The ex vivo and in vivo stability of the Ga-68 labeled peptide conjugate was tested in mouse plasma and urine. Receptor specificity was determined ex vivo by cell binding assays using human breast cancer BT474 cells. Positron emission tomography (PET)/X-ray computed tomography (CT) imaging, tissue distribution, and blocking studies were performed in mice bearing BT474 xenografts. RESULTS: The chemical and radiochemical purity was greater than 95 % and both conjugates were stable against transchelation and transmetallation. Ex vivo stability at 60 min showed that the NODAGA-peptide-bound Ga-68 reduced to 42.1 ± 3.7 % (in plasma) and 37.4 ± 2.9 % (in urine), whereas the DOTA-peptide-bound Ga-68 was reduced to 1.2 ± 0.3 % (in plasma) and 4.2 ± 0.4 % (in urine) at 60 min. Similarly, the in vivo stability for [68Ga]NODAGA-peptide was decreased to 2.1 ± 0.2 % (in plasma) and 2.2 ± 0.4 % (in urine). For [68Ga]DOTA-peptide, it was decreased to 1.4 ± 0.3 % (in plasma) and 1.2 ± 0.4 % (in urine) at 60 min. The specific BT474 cell binding was 53.9 ± 0.8 % for [68Ga]NODAGA-peptide, 25.8 ± 1.4 % for [68Ga]-DOTA-peptide, and 18.8 ± 2.5 % for [68Ga]GaCl3 at 60 min. Inveon microPET/CT imaging at 1 h post-injection showed significantly (p < 0.05) higher tumor to muscle (T/M) ratio for [68Ga]NODAGA-peptide (3.4 ± 0.3) as compared to [68Ga]DOTA-peptide (1.8 ± 0.6). For [68Ga]GaCl3 and blocked mice, their ratios were 1.5 ± 0.6 and 1.5 ± 0.3 respectively. The tissue distributions data were similar to the PET imaging data. CONCLUSION: NODAGA is superior to DOTA in terms of radiolabeling kinetics. The method of radiolabeling was reproducible and yielded higher specific activity. Although both agents have relatively low in vivo stability, PET/CT imaging studies delineated BC tumors with [68Ga]NODAGA-peptide, but not with [68Ga]DOTA-peptide.


Asunto(s)
Acetatos/farmacocinética , Radioisótopos de Galio/farmacocinética , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Péptidos/farmacocinética , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Receptores de Tipo II del Péptido Intestinal Vasoactivo/metabolismo , Receptores de Tipo I del Polipéptido Intestinal Vasoactivo/metabolismo , Acetatos/química , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Estabilidad de Medicamentos , Femenino , Radioisótopos de Galio/química , Compuestos Heterocíclicos con 1 Anillo/química , Xenoinjertos , Humanos , Ratones , Ratones Desnudos , Péptidos/química , Distribución Tisular
12.
EMBO Mol Med ; 11(1)2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30518636

RESUMEN

Though congenital hydrocephalus is heritable, it has been linked only to eight genes, one of which is MPDZ Humans and mice that carry a truncated version of MPDZ incur severe hydrocephalus resulting in acute morbidity and lethality. We show by magnetic resonance imaging that contrast medium penetrates into the brain ventricles of mice carrying a Mpdz loss-of-function mutation, whereas none is detected in the ventricles of normal mice, implying that the permeability of the choroid plexus epithelial cell monolayer is abnormally high. Comparative proteomic analysis of the cerebrospinal fluid of normal and hydrocephalic mice revealed up to a 53-fold increase in protein concentration, suggesting that transcytosis through the choroid plexus epithelial cells of Mpdz KO mice is substantially higher than in normal mice. These conclusions are supported by ultrastructural evidence, and by immunohistochemistry and cytology data. Our results provide a straightforward and concise explanation for the pathophysiology of Mpdz-linked hydrocephalus.


Asunto(s)
Permeabilidad Capilar , Proteínas Portadoras/genética , Plexo Coroideo/patología , Plexo Coroideo/fisiopatología , Hidrocefalia/patología , Hidrocefalia/fisiopatología , Animales , Medios de Contraste/análisis , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Imagen por Resonancia Magnética , Proteínas de la Membrana , Ratones
14.
Sci Rep ; 8(1): 12878, 2018 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-30150631

RESUMEN

Astrocytes are involved in various brain pathologies including trauma, stroke, neurodegenerative disorders such as Alzheimer's and Parkinson's diseases, or chronic pain. Determining cell density in a complex tissue environment in microscopy images and elucidating the temporal characteristics of morphological and biochemical changes is essential to understand the role of astrocytes in physiological and pathological conditions. Nowadays, manual stereological cell counting or semi-automatic segmentation techniques are widely used for the quantitative analysis of microscopy images. Detecting astrocytes automatically is a highly challenging computational task, for which we currently lack efficient image analysis tools. We have developed a fast and fully automated software that assesses the number of astrocytes using Deep Convolutional Neural Networks (DCNN). The method highly outperforms state-of-the-art image analysis and machine learning methods and provides precision comparable to those of human experts. Additionally, the runtime of cell detection is significantly less than that of other three computational methods analysed, and it is faster than human observers by orders of magnitude. We applied our DCNN-based method to examine the number of astrocytes in different brain regions of rats with opioid-induced hyperalgesia/tolerance (OIH/OIT), as morphine tolerance is believed to activate glia. We have demonstrated a strong positive correlation between manual and DCNN-based quantification of astrocytes in rat brain.


Asunto(s)
Astrocitos/fisiología , Modelos Biológicos , Redes Neurales de la Computación , Animales , Área Bajo la Curva , Humanos , Procesamiento de Imagen Asistido por Computador , Aprendizaje Automático , Ratas , Programas Informáticos
15.
Infect Genet Evol ; 61: 20-23, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29530659

RESUMEN

The recent reports of human infection due to H6 subtype avian influenza viruses (AIV), which are prevalent in terrestrial poultry, indicate evolution of the virus to a possible pandemic strain. Here, we report antigenic and genetic characterization of two H6N2 viruses isolated from apparently healthy domestic ducks in Kerala and Assam, India during 2014 and 2015, respectively. Hemagglutination inhibition assay revealed antigenic divergence between the two isolates, which was corroborated by amino acid differences at 55 positions (15.98%) between their hemagglutinin (HA) 1.The sequence analyses indicated that both the viruses are avian origin with avian receptor specificity, low pathogenic to poultry and sensitive to oseltamivir. However, Kerala14 had V27I mutation marker for amantadine resistance in M2. The Assam15 virus had an additional N-linked glycosylation on HA2 (position 557) compared to Kerala14 virus. Phylogenetic analysis of the HA gene revealed that both the viruses belonged to distinct lineages (Eurasian and Asia II). Phylogeny of neuraminidase and internal gene segments revealed that both the viruses are novel reassortants and are genetically distinct with different gene constellations. The results suggest independent introductions of the two H6N2 viruses into India and migratory wild birds in the Central Asian flyway might be the source of H6N2 viruses in ducks in India. Therefore, continued AIV surveillance in poultry and wild birds is essential for early detection of emergence of novel strains with pandemic potential and control of their spread.


Asunto(s)
Patos/virología , Virus de la Influenza A/genética , Gripe Aviar/virología , Virus Reordenados/genética , Animales , India , Filogenia
16.
J Clin Invest ; 128(1): 402-414, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29202476

RESUMEN

Germline mutations in the gene encoding tumor suppressor kinase LKB1 lead to gastrointestinal tumorigenesis in Peutz-Jeghers syndrome (PJS) patients and mouse models; however, the cell types and signaling pathways underlying tumor formation are unknown. Here, we demonstrated that mesenchymal progenitor- or stromal fibroblast-specific deletion of Lkb1 results in fully penetrant polyposis in mice. Lineage tracing and immunohistochemical analyses revealed clonal expansion of Lkb1-deficient myofibroblast-like cell foci in the tumor stroma. Loss of Lkb1 in stromal cells was associated with induction of an inflammatory program including IL-11 production and activation of the JAK/STAT3 pathway in tumor epithelia concomitant with proliferation. Importantly, treatment of LKB1-defcient mice with the JAK1/2 inhibitor ruxolitinib dramatically decreased polyposis. These data indicate that IL-11-mediated induction of JAK/STAT3 is critical in gastrointestinal tumorigenesis following Lkb1 mutations and suggest that targeting this pathway has therapeutic potential in Peutz-Jeghers syndrome.


Asunto(s)
Transformación Celular Neoplásica , Interleucina-11/metabolismo , Neoplasias Intestinales/metabolismo , Janus Quinasa 1/metabolismo , Janus Quinasa 2/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Serina-Treonina Quinasas/deficiencia , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Neoplasias Gástricas/metabolismo , Proteínas Quinasas Activadas por AMP , Animales , Interleucina-11/genética , Neoplasias Intestinales/genética , Neoplasias Intestinales/patología , Janus Quinasa 1/genética , Janus Quinasa 2/genética , Ratones , Ratones Noqueados , Mutación , Proteínas de Neoplasias/genética , Factor de Transcripción STAT3/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología
17.
Nucl Med Biol ; 51: 55-61, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28577428

RESUMEN

INTRODUCTION: Previously, our laboratory has shown that 64Cu-TP3805 can specifically target VPAC1 receptors and be used for positron emission tomography (PET) imaging of breast (BC) and prostate cancer (PC) in humans. Present work is aimed at the formulation of a freeze-dried diaminedithiol-peptide (N2S2-TP3805) kit and it's evaluation for the preparation of 64Cu labeled TP3805. Parameters such as pH, temperature and incubation time were examined that influenced the radiolabeling efficiency and stability of the product. METHODS: Kits were prepared under different conditions and radiolabeling efficiency of TP3805 kit was evaluated for a range of pH3.5-8.5, after addition of 64Cu in 30µl, 0.1M HCl. Incubation temperature (37-90°C) and time (30-120min.) were also investigated. Kits were stored at -10°C and their long term stability was determined as a function of their radiolabeling efficiency. Further, stability of 64Cu-TP3805 complex was evaluated in presence of fetal bovine serum and bovine serum albumin by using SDS polyacrylamide gel electrophoresis. Kits were then used for PET imaging of BC and PC following eIND (101550) and institutional approvals. Specificity of 64Cu-TP3805 for VPAC1 was examined with digital autoradiography (DAR) of prostate tissues obtained after prostatectomy, benign prostatic hyperplasia (BPH) tissue, and benign and malignant lymph nodes. Results were compared with corresponding tissue histology. RESULTS: Radiolabeling efficiency was ≥95% at final pH ~7.2 when incubated at 50°C for 90min. Kits were stable up to 18months when stored at -10°C, and 64Cu-TP3805 complex exhibited excellent stability for up to 4h at room temperature. 64Cu-TP3805 complex did not show any transchelation even after 2h incubation at 37°C in 10% FBS as well as in BSA as determined by SDS PAGE analysis. DAR identified ≥95% of malignant lesions 11 new PC lesions, 20 high grade prostatic intraepithelial neoplasia, 2/2 ejaculatory ducts and 5/5 urethra verumontanum not previously identified The malignant lymph nodes were correctly identified by DAR and for 3/3 BPH patients, and 5/5 cysts, DAR was negative. In human BC (n=19) and PC (n=26) were imaged with 100% sensitivity. CONCLUSION: Availability of ready to use N2S2-peptide kits for 64Cu labeling is convenient and eliminates possible day to day variation during its routine preparation for clinical use.


Asunto(s)
Complejos de Coordinación/química , Marcaje Isotópico/métodos , Péptidos/química , Receptores de Tipo I del Polipéptido Intestinal Vasoactivo/metabolismo , Animales , Bovinos , Complejos de Coordinación/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Masculino , Péptidos/metabolismo , Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico por imagen , Radioquímica , Albúmina Sérica Bovina/metabolismo , Temperatura
18.
Emerg Infect Dis ; 23(4): 717-719, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28117031

RESUMEN

Highly pathogenic avian influenza (H5N8) viruses were detected in waterfowl at 2 zoos in India in October 2016. Both viruses were different 7:1 reassortants of H5N8 viruses isolated in May 2016 from wild birds in the Russian Federation and China, suggesting virus spread during southward winter migration of birds.


Asunto(s)
Animales de Zoológico , Subtipo H5N8 del Virus de la Influenza A/genética , Gripe Aviar/virología , Virus Reordenados , Animales , Aves , India/epidemiología , Gripe Aviar/epidemiología , Filogenia
19.
BJU Int ; 119(6): 885-895, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28075510

RESUMEN

OBJECTIVE: To validate a hypothesis that prostate cancer can be detected non-invasively by a simple and reliable assay by targeting genomic VPAC receptors expressed on malignant prostate cancer cells shed in voided urine. PATIENTS/SUBJECTS AND METHODS: VPAC receptors were targeted with a specific biomolecule, TP4303, developed in our laboratory. With an Institutional Review Board exempt approval of use of de-identified discarded samples, an aliquot of urine collected as a standard of care, from patients presenting to the urology clinic (207 patients, 176 men and 31 women, aged ≥21 years) was cytospun. The cells were fixed and treated with TP4303 and 4,6-diamidino-2-phenylindole (DAPI). The cells were then observed under a microscope and cells with TP4303 orange fluorescence around the blue (DAPI) nucleus were considered 'malignant' and those only with a blue nucleus were regarded as 'normal'. VPAC presence was validated using receptor blocking assay and cell malignancy was confirmed by prostate cancer gene profile examination. RESULTS: The urine specimens were labelled only with gender and presenting diagnosis, with no personal health identifiers or other clinical data. The assay detected VPAC positive cells in 98.6% of the men with a prostate cancer diagnosis (141), and none of the 10 men with benign prostatic hyperplasia. Of the 56 'normal' patients, 62.5% (35 patients, 10 men and 25 women) were negative for VPAC cells; 19.6% (11, 11 men and no women) had VPAC positive cells; and 17.8% (10, four men and six women) were uninterpretable due to excessive crystals in the urine. Although data are limited, the sensitivity of the assay was 99.3% with a confidence interval (CI) of 96.1-100% and the specificity was 100% with a CI of 69.2-100%. Receptor blocking assay and fluorescence-activated cell sorting (FACS) analyses demonstrated the presence of VPAC receptors and gene profiling examinations confirmed that the cells expressing VPAC receptors were malignant prostate cancer cells. CONCLUSION: These preliminary data are highly encouraging and warrant further evaluation of the assay to serve as a simple and reliable tool to detect prostate cancer non-invasively.


Asunto(s)
Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/orina , Receptores de Tipo II del Péptido Intestinal Vasoactivo/análisis , Receptores de Tipo I del Polipéptido Intestinal Vasoactivo/análisis , Adulto , Femenino , Humanos , Masculino , Proyectos Piloto , Urinálisis/métodos , Adulto Joven
20.
Artículo en Inglés | MEDLINE | ID: mdl-27270715

RESUMEN

A large gap remains between the amount of knowledge in scientific literature and the fraction that gets curated into standardized databases, despite many curation initiatives. Yet the availability of comprehensive knowledge in databases is crucial for exploiting existing background knowledge, both for designing follow-up experiments and for interpreting new experimental data. Structured resources also underpin the computational integration and modeling of regulatory pathways, which further aids our understanding of regulatory dynamics. We argue how cooperation between the scientific community and professional curators can increase the capacity of capturing precise knowledge from literature. We demonstrate this with a project in which we mobilize biological domain experts who curate large amounts of DNA binding transcription factors, and show that they, although new to the field of curation, can make valuable contributions by harvesting reported knowledge from scientific papers. Such community curation can enhance the scientific epistemic process.Database URL: http://www.tfcheckpoint.org.


Asunto(s)
Biología Computacional/métodos , Proteínas de Unión al ADN/genética , Curaduría de Datos/métodos , Bases de Datos Genéticas , Regulación de la Expresión Génica/genética , Factores de Transcripción/genética , Animales , Minería de Datos , Humanos , Mamíferos , Ratones , Ratas
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