Cancers coopt stress-response pathways to drive oncogenesis, dodge immune surveillance, and resist cytotoxic therapies. Several of these provide protection from ferroptosis, iron-mediated oxidative cell death. Here, we found dramatic sensitization to ferroptosis upon disruption of cap-dependent translation in diffuse large B-cell lymphoma (DLBCL).
View Article and Find Full Text PDFBackground: An alternative surgical approach for hypoplastic left heart syndrome is the Hybrid pathway, which delays the risk of acute kidney injury outside of the newborn period. We sought to determine the incidence, and associated morbidity, of acute kidney injury after the comprehensive stage 2 and the cumulative incidence after the first two operations in the Hybrid pathway.
Design: A single centre, retrospective study was conducted of hypoplastic left heart patients completing the second-stage palliation in the Hybrid pathway from 2009 to 2018.
Here, we present a protocol using MATRIX (mass spectrometry analysis of active translation factors using ribosome density fractionation and isotopic labeling experiments) platform to investigate changes of the protein synthesis machinery in U87MG glioblastoma cells in response to the rocaglate silvestrol. This protocol describes steps to perform SILAC (stable isotope labeling by amino acids in cell culture), ribosome density fractionation, protein isolation, and mass spectrometry analysis. This approach can be applied to study any adaptive remodeling of protein synthesis machineries.
View Article and Find Full Text PDFIncreased protein synthesis is a requirement for malignant growth, and as a result, translation has become a pharmaceutical target for cancer. The initiation of cap-dependent translation is enzymatically driven by the eukaryotic initiation factor (eIF)4A, an ATP-powered DEAD-box RNA-helicase that unwinds the messenger RNA secondary structure upstream of the start codon, enabling translation of downstream genes. A screen for inhibitors of eIF4A ATPase activity produced an intriguing hit that, surprisingly, was not ATP-competitive.
View Article and Find Full Text PDFTactical disruption of protein synthesis is an attractive therapeutic strategy, with the first-in-class eIF4A-targeting compound zotatifin in clinical evaluation for cancer and COVID-19. The full cellular impact and mechanisms of these potent molecules are undefined at a proteomic level. Here, we report mass spectrometry analysis of translational reprogramming by rocaglates, cap-dependent initiation disruptors that include zotatifin.
View Article and Find Full Text PDFeIF4A1 is an ATP-dependent RNA helicase whose overexpression and activity have been tightly linked to oncogenesis in a number of malignancies. An understanding of the complex kinetics and conformational changes of this translational enzyme is necessary to map out all targetable binding sites and develop novel, chemically tractable inhibitors. We herein present a comprehensive quantitative analysis of eIF4A1 conformational changes using protein-ligand docking, homology modeling, and extended molecular dynamics simulations.
View Article and Find Full Text PDFObjective: Acute kidney injury leads to worse outcomes following paediatric cardiac surgery. There is a lack of literature focusing on acute kidney injury after the Hybrid stage 1 palliation for single ventricle physiology. Patients undergoing the Hybrid Stage 1, as a primary option, may have a lower incidence of kidney injury than previously reported.
View Article and Find Full Text PDFAn 8-year-old boy with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals status post complete repair including a fenestrated ventricular septal defect patch presented to the catheterization laboratory for fenestration closure. During the procedure, the catheterization wire was found to have an unusual intracardiac loop and was unable to be straightened within the heart. Three-dimensional transesophageal echocardiography revealed the wire was looped around a right ventricular papillary muscle.
View Article and Find Full Text PDFMoxetumomab pasudotox is a fusion protein of a CD22-targeting antibody and exotoxin. Minutes of exposure to Moxetumomab achieves similar cell killing than hours of exposure to a novel deimmunized variant against some acute lymphoblastic leukemia (ALL). Because blood levels fall quickly, Moxetumomab is more than 1000-fold more active than the deimmunized variant in vivo.
View Article and Find Full Text PDFMoxetumomab pasudotox (Moxe) is a chimeric protein composed of an anti-CD22 Fv fused to a portion of exotoxin A and kills CD22-expressing leukemia cells. It is very active in hairy-cell leukemia, but many children with relapsed/refractory acute lymphoblastic leukemia (ALL) either respond transiently or are initially resistant. Resistance to Moxe in cultured cells is due to low expression of diphthamide genes (DPH), but only two of six ALL blast samples from resistant patients had low DPH expression.
View Article and Find Full Text PDFObjective: Left ventricular (LV) hypertrophy (LVH) predicts adverse cardiac events in adults. We sought to determine the risk factors and prognostic significance of altered LV geometry in preterm infants.
Study Design: In an echocardiographic, single-center, retrospective case-control study we investigated the risk factors and outcomes in patients with altered LV geometry (either increased left ventricular mass index (LVMI) or increased relative wall thickness (RWT)) from a cohort of 503 preterm infants ≤2 kg.
Background: There is a paucity of normative echocardiographic data in preterm infants. The objectives of this study were to (1) derive left ventricular (LV) M-mode reference values and (2) compare the performance of alternative methods of indexing LV dimensions and LV mass (LVM) in preterm infants. The authors propose that indexing LV measures to weight in preterm infants is a practical approach given the variability associated with tape-measure length measurement in infants.
View Article and Find Full Text PDFCD22-targeted recombinant immunotoxins (rIT) are active in hairy cell leukemia or acute lymphoblastic leukemia (ALL), but not in mantle cell lymphoma (MCL) patients. The goal was to enhance rIT efficacy in vivo and to define a strong combination treatment. Activity of Moxetumomab pasudotox (Moxe) and LR combined with paclitaxel was tested against MCL cell lines in vitro and as bolus doses or continuous infusion in xenograft models.
View Article and Find Full Text PDFPurpose: Recombinant immunotoxins (rITs) targeting CD22 are highly active in hairy cell leukemia, but less so in acute lymphoblastic leukemia (ALL). This study aims to understand the variable activity of an rIT against ALL toward improving responses in clinical application.
Experimental Design: We determined in vitro activity of rITs by WST-8 assays and the time needed to kill ALL cell lines and patient-derived ALL blasts by flow cytometry.
Objective: Hereditary hemorrhagic telangiectasia is a genetic disorder characterized by visceral and mucocutaneous arteriovenous malformations (AVMs). Clinically indistinguishable hereditary hemorrhagic telangiectasia 1 and hereditary hemorrhagic telangiectasia 2 are caused by mutations in ENG and ALK1, respectively. In this study, we have compared the development of visceral and mucocutaneous AVMs in adult stages between Eng- and Alk1-inducible knockout (iKO) models.
View Article and Find Full Text PDFOrganisms must make important decisions on how to allocate resources to reproduction. We investigated allocation decisions in the social wasp Vespula maculifrons to understand how social insects make reproductive choices. We first determined how annual colonies apportioned resources to growth and reproduction by analysing developing brood.
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