Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Pediatr Dev Pathol ; : 10935266241264161, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39056566

RESUMEN

Umbilical cord hemangiomas are rare lesions, for which data on pregnancy outcome is lacking. This study combines a multi-institution 4-case series with a systematic literature search (n = 52) to determine possible pathologic lesion parameters which may have an effect on pregnancy outcome. Of all 56 pregnancies, lesion size ranged from 0.2 to 23.0 cm with pregnancy outcomes ranging from healthy liveborns (58.9%), liveborns with severe complications largely due to prematurity and/or fluid overload (12.5%), intrauterine/neonatal demise (25.0%), and pregnancy termination (3.6%). Of the 52 cases included for statistical analysis, there was no significant association between fetal outcome and vascular lesion location (P = .12) or fetal outcome and single umbilical artery involvement versus involvement of other vasculature (P = .29). The mean length of vascular lesions that resulted in healthy liveborns did not significantly differ from those resulting in severe fetal complications and/or demise (P = .72). Cases resulting in severe complications and/or demise were significantly earlier at delivery than those resulting in healthy liveborns (P < .001). Combined findings suggest that functional lesion characteristics, such as the degree of turbulent flow generated, have more significance than size, especially in early gestation losses. Moving forward, standardized reporting of pathologic lesion characteristics is paramount to better predict pregnancy prognosis.

2.
bioRxiv ; 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38559147

RESUMEN

Uterine natural killer cells (uNKs) are a tissue resident lymphocyte population that are critical for pregnancy success. Although mouse models have demonstrated that NK deficiency results in abnormal placentation and poor pregnancy outcomes, the generalizability of this knowledge to humans remains unclear. Here we identify uterus transplant (UTx) recipients as a human population with reduced endometrial NK cells and altered pregnancy phenotypes. We further show that the NK reduction in UTx is due to impaired transcriptional programming of NK tissue residency due to blockade of the transcription factor nuclear factor of activated T cells (NFAT). NFAT-dependent genes played a role in multiple molecular circuits governing tissue residency in uNKs, including early residency programs involving AP-1 transcription factors as well as TGFß-mediated upregulation of surface integrins. Collectively, our data identify a previously undescribed role for NFAT in uterine NK tissue residency and provide novel mechanistic insights into the biologic basis of pregnancy complications due to alteration of tissue resident NK subsets in humans. One Sentence Summary: Role of NFAT in uterine NK cell tissue residency.

3.
Placenta ; 139: 127-133, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37390516

RESUMEN

INTRODUCTION: Prenatal exposure to stress has been associated with poor pregnancy outcomes, yet evidence linking stress and placental size is limited. Asthma is associated with worse pregnancy outcomes and women with asthma may be more susceptible to stress. Using the asthma-enriched B-WELL-Mom cohort, we examined the association between perceived stress and placental size. METHODS: Placental measures of weight, length, width, and thickness were available for 345 women (262 with asthma) via placental pathology report. Perceived Stress Scale (PSS) scores were obtained in each trimester of pregnancy and categorized into quartiles (low quartile as reference). For associations between PSS and placental size, generalized estimating equations adjusted for maternal and infant factors were used to estimate regression coefficients (ß) and 95% confidence intervals (95% CI). Full models and models stratified by asthma status were run. RESULTS: Compared to Quartile 1, high levels of stress (Quartile 4) were associated with smaller placental weight (-20.63 95% CI: -37.01,-4.26) and length (-0.55 95% CI: -0.96,-0.15), but not width or thickness. Results by asthma status show a stronger association between perceived stress and shorter placental length in those with asthma and a stronger association between perceived stress and smaller placental thickness in those without asthma. Findings were robust to sensitivity analyses DISCUSSION: Higher levels of perceived stress were associated with smaller placental size. Additional research is warranted to understand the relationship between stress and placental size.


Asunto(s)
Asma , Efectos Tardíos de la Exposición Prenatal , Embarazo , Humanos , Femenino , Placenta/patología , Efectos Tardíos de la Exposición Prenatal/patología , Resultado del Embarazo , Asma/patología , Estrés Psicológico , Exposición Materna
5.
Am J Obstet Gynecol ; 228(5): 497-508.e4, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36549567

RESUMEN

Pathologic examination of the placenta can provide insight into likely (and unlikely) causes of antepartum and intrapartum events, diagnoses with urgent clinical relevance, prognostic information for mother and infant, support for practice evaluation and improvement, and insight into advancing the sciences of obstetrics and neonatology. Although it is true that not all placentas require pathologic examination (although alternative opinions have been expressed), prioritization of placentas for pathologic examination should be based on vetted indications such as maternal comorbidities or pregnancy complications in which placental pathology is thought to be useful for maternal or infant care, understanding pathophysiology, or practice modifications. Herein we provide placental triage criteria for the obstetrical and neonatal provider based on publications and expert opinion of 16 placental pathologists and a pathologists' assistant, formulated using a modified Delphi approach. These criteria include indications in which placental pathology has clinical relevance, such as pregnancy loss, maternal infection, suspected abruption, fetal growth restriction, preterm birth, nonreassuring fetal heart testing requiring urgent delivery, preeclampsia with severe features, or neonates with early evidence of multiorgan system failure including neurologic compromise. We encourage a focused gross examination by the provider or an attendant at delivery for all placentas and provide guidance for this examination. We recommend that any placenta that is abnormal on gross examination undergo a complete pathology examination. In addition, we suggest practice criteria for placental pathology services, including a list of critical values to be used by the relevant provider. We hope that these sets of triage indications, criteria, and practice suggestions will facilitate appropriate submission of placentas for pathologic examination and improve its relevance to clinical care.


Asunto(s)
Obstetricia , Complicaciones del Embarazo , Nacimiento Prematuro , Embarazo , Recién Nacido , Femenino , Humanos , Placenta/patología , Retardo del Crecimiento Fetal/patología
6.
Pediatr Dev Pathol ; 25(3): 278-284, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34958254

RESUMEN

INTRODUCTION: Ornithine transcarbamylase (OTC) deficiency is the most common urea cycle disorder, inherited in an X-linked manner. Males are severely affected. Female phenotypes vary from asymptomatic to severe, and symptoms may be triggered by high metabolic states like childbirth. Literature on OTC deficiency in pregnancy and placental pathology is limited. METHODS: Pathology records were searched at a single referral center from 2000-2020 and identified three placental cases from two mothers heterozygous for OTC deficiency. Placental pathology and maternal and neonatal history were reviewed in detail. RESULTS: The placenta from one symptomatic mother carrying an affected male fetus showed widespread high-grade fetal vascular malperfusion (FVM) lesions of varying age. These lesions were not seen in the two placentas from the asymptomatic mother. DISCUSSION: In cases of symptomatic maternal OTC deficiency, our findings highlight the need for placental examination. Since thrombotic events in the placenta have the potential to associate with fetal and neonatal endothelial damage, a high index of suspicion for neonatal thrombosis may be warranted.


Asunto(s)
Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa , Femenino , Heterocigoto , Humanos , Masculino , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/diagnóstico , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/genética , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/patología , Placenta/patología , Embarazo
7.
Pediatr Dev Pathol ; 23(2): 115-120, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31362580

RESUMEN

BACKGROUND: Antitumor necrosis alpha (TNFα) therapy is often used in the management of patients with inflammatory bowel disease (IBD) and may have effects on lymphoid tissue architecture and function. The goal of our study was to characterize the effects of TNFα inhibitors on mesenteric lymph node and mucosa-associated lymphoid tissue in patients with IBD. METHODS: We examined lymphoid tissue morphology in IBD patients treated with TNFα inhibitors compared to untreated controls. Intestinal resections from 19 patients (10 anti-TNFα treated and 9 controls) were reviewed. Immunohistochemistry for CD21, CD20, and CD3 was performed on ileocecal valve lymphoid tissue and mesenteric lymph nodes from the resection specimens to assess follicular architecture. RESULTS: Relative to control groups, TNFα-treated groups showed less preserved germinal center architecture, evidenced by lower overall semiquantitative scores for follicular architecture. Likewise, the percentage of secondary follicles to total follicles was decreased in patients treated with TNFα blockade. CONCLUSIONS: Our results suggest that TNFα inhibitors may play a role in disruption of lymphoid germinal center architecture in patients with IBD. Awareness of this disrupted lymphoid morphology when examining histologic sections from patients with IBD treated with TNFα inhibitors may prevent unnecessary studies to exclude a lymphoproliferative disorder.


Asunto(s)
Antiinflamatorios/administración & dosificación , Enfermedades Inflamatorias del Intestino/patología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab/administración & dosificación , Adolescente , Niño , Células Dendríticas/patología , Femenino , Humanos , Válvula Ileocecal/patología , Inmunohistoquímica , Infliximab/administración & dosificación , Mucosa Intestinal/patología , Intestino Delgado/patología , Ganglios Linfáticos/patología , Tejido Linfoide/patología , Masculino
8.
Ann Neurol ; 86(1): 42-54, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31074527

RESUMEN

OBJECTIVE: To test whether systemic cytokine release is associated with central nervous system inflammatory responses and glial injury in immune effector cell-associated neurotoxicity syndrome (ICANS) after chimeric antigen receptor (CAR)-T cell therapy in children and young adults. METHODS: We performed a prospective cohort study of clinical manifestations as well as imaging, pathology, CSF, and blood biomarkers on 43 subjects ages 1 to 25 who received CD19-directed CAR/T cells for acute lymphoblastic leukemia (ALL). RESULTS: Neurotoxicity occurred in 19 of 43 (44%) subjects. Nine subjects (21%) had CTCAE grade 3 or 4 neurological symptoms, with no neurotoxicity-related deaths. Reversible delirium, headache, decreased level of consciousness, tremor, and seizures were most commonly observed. Cornell Assessment of Pediatric Delirium (CAPD) scores ≥9 had 94% sensitivity and 33% specificity for grade ≥3 neurotoxicity, and 91% sensitivity and 72% specificity for grade ≥2 neurotoxicity. Neurotoxicity correlated with severity of cytokine release syndrome, abnormal past brain magnetic resonance imaging (MRI), and higher peak CAR-T cell numbers in blood, but not cerebrospinal fluid (CSF). CSF levels of S100 calcium-binding protein B and glial fibrillary acidic protein increased during neurotoxicity, indicating astrocyte injury. There were concomitant increases in CSF white blood cells, protein, interferon-γ (IFNγ), interleukin (IL)-6, IL-10, and granzyme B (GzB), with concurrent elevation of serum IFNγ IL-10, GzB, granulocyte macrophage colony-stimulating factor, macrophage inflammatory protein 1 alpha, and tumor necrosis factor alpha, but not IL-6. We did not find direct evidence of endothelial activation. INTERPRETATION: Our data are most consistent with ICANS as a syndrome of systemic inflammation, which affects the brain through compromise of the neurovascular unit and astrocyte injury. ANN NEUROL 2019.


Asunto(s)
Antígenos CD19/efectos adversos , Inmunoterapia Adoptiva/efectos adversos , Neuroglía/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico por imagen , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Antígenos CD19/administración & dosificación , Antígenos CD19/inmunología , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Inmunoterapia Adoptiva/tendencias , Lactante , Masculino , Neuroglía/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Estudios Prospectivos , Adulto Joven
9.
Pediatr Dev Pathol ; 21(6): 522-527, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29490565

RESUMEN

Malignant rhabdoid tumors (MRT; atypical teratoid/rhabdoid tumor [ATRT] in the central nervous system) are aggressive tumors in infants and children which can overlap with other sarcomas, such as synovial sarcoma (SS). The gold standard for SS diagnosis is characterization of the t(X;18) chromosomal translocation. However, stratification of cases for molecular analysis is not always straightforward or feasible. Recent literature suggests transducer-like enhancer of split 1 (TLE1) protein expression may distinguish SS from certain histologic mimics; however, this has not been investigated in MRT and ATRT. We stained whole-tissue sections of 18 archived cases of MRT and ATRT with TLE1. Nuclear expression was scored using a 4-tiered (0, 1+, 2+, and 3+) scale describing staining intensity, extent, or combination of both. The majority of MRT and ATRT cases showed some TLE1 immunoreactivity (n = 16; 89% for ≥1 + staining); 14 (78%) of total cases showed ≥2 + positivity using any of the 3 scoring systems. Over half (n = 10; 56%) of cases showed ≥2 + staining; 4 (22%) cases showed 3 + strong and diffuse TLE1 staining measured by all scoring systems in agreement. Although still of potential use, we urge caution in the interpretation of TLE1 when the differential diagnosis includes both SS and MRT or ATRT.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Complejas y Mixtas/diagnóstico , Proteínas Represoras/metabolismo , Tumor Rabdoide/diagnóstico , Neoplasias de los Tejidos Blandos/diagnóstico , Teratoma/diagnóstico , Adolescente , Niño , Preescolar , Proteínas Co-Represoras , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Masculino , Neoplasias Complejas y Mixtas/metabolismo , Tumor Rabdoide/metabolismo , Neoplasias de los Tejidos Blandos/metabolismo , Teratoma/metabolismo
10.
Bioorg Med Chem Lett ; 27(3): 675-678, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28043798

RESUMEN

Our initial discovery of 8-hydroxyquinoline inhibitors of BoNT/A and separation/testing of enantiomers of one of the more active leads indicated considerable flexibility in the binding site. We designed a limited study to investigate this flexibility and probe structure-activity relationships; utilizing the Betti reaction, a 36 compound matrix of quinolinol BoNT/A LC inhibitors was developed using three 8-hydroxyquinolines, three heteroaromatic amines, and four substituted benzaldehydes. This study has revealed some of the most effective quinolinol-based BoNT/A inhibitors to date, with 7 compounds displaying IC50 values ⩽1µM and 11 effective at ⩽2µM in an ex vivo assay.


Asunto(s)
Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Hidroxiquinolinas/química , Animales , Sitios de Unión , Toxinas Botulínicas Tipo A/metabolismo , Hidroxiquinolinas/metabolismo , Hidroxiquinolinas/toxicidad , Concentración 50 Inhibidora , Ratones , Nervio Frénico/efectos de los fármacos , Nervio Frénico/metabolismo , Unión Proteica , Serogrupo , Relación Estructura-Actividad
11.
Leuk Lymphoma ; 58(1): 179-184, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27184221

RESUMEN

Runt-related transcription factor-3 (RUNX3) is an apoptotic factor correlated with tumorigenesis and cancer progression. Enhancer of zeste homolog-2 (EZH2), a histone methyltransferase, has been shown to mediate silencing of RUNX3. We investigated RUNX3 and EZH2 expression in diffuse large B-cell lymphoma (DLBCL). A chart review was conducted and tissue-microarray (TMA) was constructed using archived tissue from 83 DLBCL cases. RUNX3 and EZH2 protein expression was correlated with immunophenotypic subtypes and survival. Loss of RUNX3 was observed in 20 cases; EZH2 expression was observed in 59 cases. RUNX3-negative tumors had significantly lower overall and recurrence-free survival (log-rank test, p < 0.0001 for each). No correlation was found between RUNX3 and EZH2 staining (r = 0.14; p = 0.2). Results suggest a role for the RUNX3 gene in the pathogenesis of DLBCL. Loss of RUNX3 expression strongly correlated with adverse prognosis, independent of subtype. Further studies are warranted to elucidate the biology and prognostic utility of RUNX3 in DLBCL.


Asunto(s)
Biomarcadores de Tumor , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Linfoma de Células B Grandes Difuso/genética , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia
12.
Int J Surg Pathol ; 24(8): 753-756, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27422470

RESUMEN

Intrasellar rhabdomyosarcoma is rare, and when arising in collusion with an unrelated entity, can present a diagnostic pitfall. We describe a case of a 56-year-old woman who presented with right eye ptosis and a pituitary mass, which was resected and diagnosed as atypical pituitary adenoma. Because of residual disease and atypical pathology, the patient received adjuvant radiation. Tumor recurrence was noted after 5 months, and a second resection was performed. Nests of atypical pituitary adenoma cells within an exuberant spindle cell stroma were noted, with areas of presumed radiation necrosis. A second recurrence prompted a third resection. After expert consultation and additional immunohistochemical stains for muscle markers, a diagnosis was rendered of primary rhabdomyosarcoma arising in association with a pituitary adenoma. Despite its rarity, a high index of suspicion for rhabdomyosarcoma arising within a pituitary adenoma should be maintained in cases of atypical pituitary adenoma with a stromal response.


Asunto(s)
Adenoma/patología , Neoplasias Primarias Múltiples/patología , Neoplasias Hipofisarias/patología , Rabdomiosarcoma/patología , Adenoma/diagnóstico , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/patología , Neoplasias Primarias Múltiples/diagnóstico , Neoplasias Hipofisarias/diagnóstico , Rabdomiosarcoma/diagnóstico
13.
Int J Surg Pathol ; 24(7): 653-5, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27422471

RESUMEN

We report a case of a 53-year-old woman who presented with rectal bleeding and a 9.5 cm hemicircumferential ascending colon mass. Histology revealed adenosquamous carcinoma (ASC), a rare subtype comprised of malignant squamous and glandular elements. Immunohistochemistry revealed loss of MLH1/PMS2 expression and retained MSH2/MSH6 expression in squamous and glandular components, indicative of microsatellite instability (MSI). MSI is caused by loss-of-function defects in DNA mismatch repair genes, leading to increased susceptibility to a variety of neoplasms; the role of MSI in colorectal ASC is unknown. The tumor was negative for MLH1 gene promoter hypermethylation, the patient had a germline MLH1 mutation, and met criteria for Lynch syndrome. To our knowledge this is the first report of a MSI-high colorectal carcinoma (CRC) showing adenosquamous histology. Further evaluation of MSI status in colorectal ASC may be warranted as this may be another histologic type of CRC associated with MSI.


Asunto(s)
Carcinoma Adenoescamoso/patología , Neoplasias del Colon/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Biomarcadores de Tumor/análisis , Carcinoma Adenoescamoso/diagnóstico , Neoplasias del Colon/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Femenino , Mutación de Línea Germinal , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL/genética , Reacción en Cadena de la Polimerasa
15.
Toxicon ; 98: 12-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25707753

RESUMEN

Two small molecular weight inhibitors, compounds CB7969312 and CB7967495, that displayed inhibition of botulinum neurotoxin serotype A in a previous study, were evaluated for inhibition of botulinum neurotoxin serotypes B, C, E, and F. The small molecular weight inhibitors were assessed by molecular modeling, UPLC-based peptide cleavage assay; and an ex vivo assay, the mouse phrenic nerve - hemidiaphragm assay (MPNHDA). While both compounds were inhibitors of botulinum neurotoxin (BoNT) serotypes B, C, and F in the MPNHDA, compound CB7969312 was effective at lower molar concentrations than compound CB7967495. However, compound CB7967495 was significantly more effective at preventing BoNTE intoxication than compound CB7969312. In the UPLC-based peptide cleavage assay, CB7969312 was also more effective against LcC. Both compounds inhibited BoNTE, but not BoNTF, LcE, or LcF in the UPLC-based peptide cleavage assay. Molecular modeling studies predicted that both compounds would be effective inhibitors of BoNTs B, C, E, and F. But CB7967495 was predicted to be a more effective inhibitor of the four serotypes (B, C, E, and F) than CB7969312. This is the first report of a small molecular weight compound that inhibits serotypes B, C, E, and F in the ex vivo assay.


Asunto(s)
Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Toxinas Botulínicas/antagonistas & inhibidores , Clostridium botulinum/química , Aminopiridinas/química , Animales , Toxinas Botulínicas/química , Toxinas Botulínicas Tipo A/química , Células Cultivadas , Hidroxiquinolinas/química , Ratones , Estructura Molecular , Peso Molecular , Nervio Frénico/efectos de los fármacos , Conformación Proteica
16.
ACS Med Chem Lett ; 3(5): 387-91, 2012 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-24900483

RESUMEN

An in silico screen of the NIH Molecular Library Small Molecule Repository (MLSMR) of ∼350000 compounds and confirmatory bioassays led to identification of chaetochromin A (1) as an inhibitor of botulinum neurotoxin serotype A (BoNT A). Subsequent acquisition and testing of analogues of 1 uncovered two compounds, talaroderxines A (2) and B (3), with improved activity. These are the first fungal metabolites reported to exhibit BoNT/A inhibitory activity.

17.
ACS Med Chem Lett ; 2(5): 396-401, 2011 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-22102940

RESUMEN

The racemic product of the Betti reaction of 5-chloro-8-hydroxyquinoline, benzaldehyde and 2-aminopyridine was separated by chiral HPLC to determine which enantiomer inhibited botulinum neurotoxin serotype A. When the enantiomers unexpectedly proved to have comparable activity, the absolute structures of (+)-(R)-1 and (-)-(S)-1 were determined by comparison of calculated and observed circular dichroism spectra. Molecular modeling studies were undertaken in an effort to understand the observed bioactivity and revealed different ensembles of binding modes, with roughly equal binding energies, for the two enantiomers.

18.
Arch Biochem Biophys ; 491(1-2): 75-84, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19772855

RESUMEN

Quinolinol derivatives were found to be effective inhibitors of botulinum neurotoxin serotype A (BoNT/A). Studies of the inhibition and binding of 7-(phenyl(8-quinolinylamino)methyl)-8-quinolinol (QAQ) to the light chain domain (BoNT/A LC) showed that QAQ is a non-competitive inhibitor for the zinc protease activity. Binding and molecular modeling studies reveal that QAQ binds to a hydrophobic pocket near the active site. Its inhibitor effect does not involve the removal of zinc ion from the light chain. A 24-mer SNAP-25 peptide containing E183 to G206 with Q197C mutation (Peptide C) binds to BoNT/A LC with an unusually slow second order binding rate constant of 76.7M(-1)s(-1). QAQ binds to Zn(2+)-free BoNT/A LC with a K(D) of 0.67microM and to Peptide C-BoNT/A LC complex with a K(D) of 2.33microM. The insights of the interactions of quinolinols and peptides with the zinc protease of BoNT/A should aid in the development of inhibitors of metalloproteases.


Asunto(s)
Aminoquinolinas/farmacología , Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Hidroxiquinolinas/farmacología , Metaloendopeptidasas/antagonistas & inhibidores , Péptidos/farmacología , Inhibidores de Proteasas/farmacología , Zinc/metabolismo , Secuencia de Aminoácidos , Aminoquinolinas/química , Aminoquinolinas/metabolismo , Toxinas Botulínicas Tipo A/química , Toxinas Botulínicas Tipo A/metabolismo , Dominio Catalítico , Quelantes/química , Quelantes/metabolismo , Quelantes/farmacología , Concentración de Iones de Hidrógeno , Hidroxiquinolinas/química , Hidroxiquinolinas/metabolismo , Cinética , Metaloendopeptidasas/química , Metaloendopeptidasas/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Péptidos/química , Péptidos/metabolismo , Inhibidores de Proteasas/química , Inhibidores de Proteasas/metabolismo , Estructura Terciaria de Proteína , Espectrometría de Fluorescencia , Temperatura
19.
Antimicrob Agents Chemother ; 53(8): 3478-86, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19528275

RESUMEN

An integrated strategy that combined in silico screening and tiered biochemical assays (enzymatic, in vitro, and ex vivo) was used to identify and characterize effective small-molecule inhibitors of Clostridium botulinum neurotoxin serotype A (BoNT/A). Virtual screening was initially performed by computationally docking compounds of the National Cancer Institute (NCI) database into the active site of BoNT/A light chain (LC). A total of 100 high-scoring compounds were evaluated in a high-performance liquid chromatography (HPLC)-based protease assay using recombinant full-length BoNT/A LC. Seven compounds that significantly inhibited the BoNT/A protease activity were selected. Database search queries of the best candidate hit [7-((4-nitro-anilino)(phenyl)methyl)-8-quinolinol (NSC 1010)] were performed to mine its nontoxic analogs. Fifty-five analogs of NSC 1010 were synthesized and examined by the HPLC-based assay. Of these, five quinolinol derivatives that potently inhibited both full-length BoNT/A LC and truncated BoNT/A LC (residues 1 to 425) were selected for further inhibition studies in neuroblastoma (N2a) cell-based and tissue-based mouse phrenic nerve hemidiaphragm assays. Consistent with enzymatic assays, in vitro and ex vivo studies revealed that these five quinolinol-based analogs effectively neutralized BoNT/A toxicity, with CB 7969312 exhibiting ex vivo protection at 0.5 microM. To date, this is the most potent BoNT/A small-molecule inhibitor that showed activity in an ex vivo assay. The reduced toxicity and high potency demonstrated by these five compounds at the biochemical, cellular, and tissue levels are distinctive among the BoNT/A small-molecule inhibitors reported thus far. This study demonstrates the utility of a multidisciplinary approach (in silico screening coupled with biochemical testing) for identifying promising small-molecule BoNT/A inhibitors.


Asunto(s)
Antitoxinas/farmacología , Toxinas Botulínicas Tipo A/antagonistas & inhibidores , Toxinas Botulínicas Tipo A/metabolismo , Clostridium botulinum/metabolismo , Hidroxiquinolinas/farmacología , Nervio Frénico/efectos de los fármacos , Animales , Antitoxinas/química , Toxinas Botulínicas Tipo A/genética , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Bases de Datos Factuales , Femenino , Hidroxiquinolinas/síntesis química , Hidroxiquinolinas/química , Técnicas In Vitro , Ratones , Estructura Molecular
20.
Cancer Microenviron ; 2(1): 9-21, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19308679

RESUMEN

Stromal fibroblasts influence the behavior of breast epithelial cells. Fibroblasts derived from normal breast (NAF) inhibit epithelial growth, whereas fibroblasts from breast carcinomas (CAF) have less growth inhibitory capacity and can promote epithelial growth. We sought to identify molecules that are differentially expressed in NAF versus CAF and potentially responsible for their different growth regulatory abilities. To determine the contribution of soluble molecules to fibroblast-epithelial interactions, NAF were grown in 3D, transwell or direct contact co-cultures with MCF10AT epithelial cells. NAF suppressed proliferation of MCF10AT in both direct contact and transwell co-cultures, but this suppression was significantly greater in direct co-cultures, indicating involvement of both soluble and contact factors. Gene expression profiling of early passage fibroblast cultures identified 420 genes that were differentially expressed in NAF versus CAF. Of the eight genes selected for validation by real-time PCR, FIBULIN 1, was overexpressed in NAF, and DICKKOPF 1, NEUREGULIN 1, PLASMINOGEN ACTIVATOR INHIBITOR 2, and TISSUE PLASMINOGEN ACTIVATOR were overexpressed in CAF. A higher expression of FIBULIN 1 in normal- than cancer-associated fibroblastic stroma was confirmed by immunohistochemistry of breast tissues. Among breast cancers, stromal expression of Fibulin 1 protein was higher in estrogen receptor alpha-positive cancers and low stromal expression of Fibulin 1 correlated with a higher proliferation of cancer epithelial cells. In conclusion, expression profiling of NAF and CAF cultures identified many genes with potential relevance to fibroblast-epithelial interactions in breast cancer. Furthermore, these early passage fibroblast cultures can be representative of gene expression in stromal fibroblasts in vivo.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...