Angiosarcomas are rare, malignant soft tissue tumors in children that arise in a wide range of anatomical locations and have limited targeted therapies available. Here, we report a rare case of a pediatric angiosarcoma (pAS) with Li-Fraumeni syndrome (LFS) expressing a novel gene fusion. Although both and are established proto-oncogenes, our study is the first to describe the mechanistic role of - fusion arising via intrachromosomal rearrangement.
View Article and Find Full Text PDFBackground:: The ganglioside G is a potential circulating tumor biomarker for the childhood cancer neuroblastoma. Interpreting the levels of a circulating tumor biomarker depends in part on a knowledge of the biomarker’s clinical pharmacology.
Methods:: We studied the plasma and cerebrospinal fluid (CSF) pharmacokinetics of the C lipoform of G in two nonhuman primates with indwelling subcutaneous CSF lateral ventricular reservoir systems.
This study scrutinizes management and clinical presentation of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) in pediatric inpatient care and evaluates the utilization of pediatric healthcare capacity during the pandemic. Within this retrospective cohort study, we systematically reviewed data of all 16,785 pediatric patients (<18 years admitted to our clinical center between January 2018 and June 2021). Data on SARS-CoV-2 test numbers, hospital admissions and clinical characteristics of infected patients were collected.
View Article and Find Full Text PDFPediatr Blood Cancer
January 2020
Background: G is a ganglioside that is ubiquitously expressed in the plasma membrane of neuroblastoma and is shed into the circulation.
Procedure: G was measured with a high-pressure liquid chromatography/tandem mass spectrometry assay in serum or plasma from 40 children without cancer (controls) and in biobanked samples from 128 (73 high-risk) children with neuroblastic tumors at diagnosis, 56 children with relapsed neuroblastoma, 14 children with high-risk neuroblastoma after treatment, and 8 to 12 children each with 10 other common childhood cancers at diagnosis.
Results: The C (18 carbon fatty acid) lipoform was the predominant circulating form of G in controls and in patients with neuroblastoma.
Pediatric low-grade gliomas (PLGGs) are frequently associated with activating gene fusions, such as KIAA1549-BRAF, that aberrantly drive the mitogen activated protein kinase (MAPK) pathway. Although RAF inhibitors (RAFi) have been proven effective in BRAF-V600E mutant tumors, we have previously shown how the KIAA1549-BRAF fusion can be paradoxically activated by RAFi. While newer classes of RAFi, such as PLX8394, have now been shown to inhibit MAPK activation by KIAA1549-BRAF, we sought to identify alternative MAPK pathway targeting strategies using clinically relevant MEK inhibitors (MEKi), along with potential escape mechanisms of acquired resistance to single-agent MAPK pathway therapies.
View Article and Find Full Text PDFBisphenol A (BPA) is an endocrine disrupting chemical with ubiquitous environmental exposure. Animal studies have demonstrated that in utero BPA exposure leads to increased adult body weight. Our aim was to characterize human fetal BPA exposure by measuring BPA concentration in second trimester amniotic fluid (AF) samples and to study its relationship with birth weight (BW) in full term infants.
View Article and Find Full Text PDFA multiplexed quantitative method for the analysis of three major unconjugated steroids in human serum by stable isotope dilution liquid chromatography-high resolution mass spectrometry (LC-HRMS) was developed and validated on a Q Exactive Plus hybrid quadrupole/Orbitrap mass spectrometer. This quantification utilized isotope dilution and Girard P derivatization on the keto-groups of testosterone (T), androstenedione (AD) and dehydroepiandrosterone (DHEA) to improve ionization efficiency using electrospray ionization. Major isomeric compounds to T and DHEA; the inactive epimer of testosterone (epiT), and the metabolite of AD, 5α-androstanedione (5α-AD) were completely resolved on a biphenyl column within an 18min method.
View Article and Find Full Text PDFHumans perceive the world from an egocentric perspective, while being able to mentally take a third person's perspective. Graphesthesia tasks revealed that letters written on the back of one's own head are consistently perceived from an embodied perspective, while the perspective on one's front is less consistent and often disembodied. We developed a cutaneous gap bisection task as a more discrete measure of the perspective on the body.
View Article and Find Full Text PDFBackground: Absolute quantification of protein biomarkers such as serum apolipoprotein A1 by both immunoassays and LC-MS can provide misleading results.
Results: Recombinant ApoA-1 internal standard was prepared using stable isotope labeling by amino acids in cell culture with [(13)C6(15)N2]-lysine and [(13)C9(15)N1]-tyrosine in human cells. A stable isotope dilution LC-MS method for serum ApoA-1 was validated and levels analyzed for 50 nonsmokers and 50 smokers.
A novel approach to pancreatic cancer biomarker discovery has been developed, which employs a stable isotope labeled proteome (SILAP) standard coupled with extensive multidimensional separation coupled with tandem mass spectrometry (MS/MS). Secreted proteins from CAPAN-2 human pancreatic cancer derived cells were collected after conducting stable isotope labeling by amino acids in cell culture (SILAC). The resulting SILAP standard contained <0.
View Article and Find Full Text PDFTranslocations and other aberrations involving the MLL (mixed lineage leukemia) gene result in aggressive forms of leukemias. Heterogeneity in partner genes, in chromosomal breakpoints, in MLL itself, and in the different partner genes results in heterogeneous fusion transcripts that can be alternatively spliced, which complicates deciphering a unifying mechanism of leukemogenesis. However, recent microarray studies completed with clinical leukemia specimens have uncovered several distinct mRNA signatures within MLL leukemia that differ from other types of leukemia.
View Article and Find Full Text PDFThe purpose of this study was to identify isozyme-specific antibodies and use them to determine the expression levels of four P450 3A enzymes in the livers of vehicle- and pregnenolone 16alpha-carbonitrile (PCN)-treated rats of both sexes, since previous work on mRNA levels has shown considerable sexual dimorphism. Using Western blot analysis with four isozyme-specific antibodies, we show that P450 3A1, 3A2, and 3A9 were expressed in vehicle-treated adult female rats at very low levels whereas P450 3A18 was not detected. PCN treatment of females strongly induced the expression of P450 3A1 in the livers with protein product increases of 214-, 3-, and 5-fold for P450 3A1, 3A2, and 3A9, respectively, and P450 3A18 was induced to 3.
View Article and Find Full Text PDFIn this study we describe the mapping of epitopes on CYP3A4/5 recognized by a panel of monoclonal antibodies (MAbs). CYP3A4 and CYP3A5 cDNAs were cloned in GST expression vectors and the fusion proteins were subjected to Western blot. Eight MAbs reacted with the full-length GST-3A4 fusion protein as well as baculovirus cDNA-expressed CYP3A4, while six of these reacted with baculovirus cDNA-expressed CYP3A5.
View Article and Find Full Text PDFObjective: Our objective was to characterize the oxidative metabolism of estradiol by human term placenta and its modulation by cigarette smoking.
Methods: Placental microsomes were prepared from term placentas obtained from 13 cigarette smokers (20 to 30 cigarettes per day until the time of delivery) and 13 control subjects who were nonsmokers. Estrogen metabolism was studied by incubation of 250 nmol/L [(3)H]estradiol with placental microsomes and NADPH, and the estrogen metabolites were determined by HPLC and gas chromatography-mass spectrometry.