Publications by authors named "Daniel R O' Brien"

Article Synopsis
  • High-grade follicular cell-derived non-anaplastic thyroid carcinomas are rare tumors, particularly in patients under 21, and are more commonly diagnosed in older adults.
  • A study focused on 15 patients aged 9-20 revealed various classifications of thyroid carcinoma, including poorly differentiated and differentiated high-grade types, with specific genetic alterations noted, especially in the DICER1 and TP53 genes.
  • Immunohistochemistry tests indicated the presence of BRAF V600E mutations and PTEN alterations, highlighting the molecular complexity of these thyroid cancers in younger populations.
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Chronic lymphocytic leukemia (CLL) is characterized by multiple copy number alterations (CNAs) and somatic mutations that are central to disease prognosis, risk stratification, and mechanisms of therapy resistance. Fluorescence in situ hybridization (FISH) panels are widely used in clinical applications as the gold standard for screening prognostic chromosomal abnormalities in CLL. DNA sequencing is an alternative approach to identifying CNAs but is not an established method for clinical CNA screening.

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Article Synopsis
  • Upamostat is a potent oral serine protease inhibitor that targets trypsin enzymes and uPA, which are linked to cancer invasion, while opaganib selectively inhibits sphingosine kinase 2 involved in cancer growth.
  • The study aimed to evaluate the antitumor effects of upamostat and opaganib, both separately and together, on cholangiocarcinoma tumors in nude mice.
  • Results indicated that treatments with upamostat, opaganib, or their combination significantly reduced tumor volumes compared to the control group.
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  • Cholangiocarcinoma (CCA) is a challenging type of cancer with poor immune response and survival rates, necessitating advanced mouse models to study its tumor microenvironment and immune evasion strategies.
  • The study developed new immunocompetent mouse models of intrahepatic CCA (iCCA) that accurately replicate human disease, allowing researchers to analyze tumor genomics and immune characteristics.
  • Results showed that different genetic mouse models exhibited unique tumor mutation patterns and immune responses, highlighting the need for varied preclinical models to effectively test immunotherapy treatments.
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Background & Aims: The PTEN-AKT pathway is frequently altered in extrahepatic cholangiocarcinoma (eCCA). We aimed to evaluate the role of PTEN in the pathogenesis of eCCA and identify novel therapeutic targets for this disease.

Methods: The Pten gene was genetically deleted using the Cre-loxp system in biliary epithelial cells.

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Key Points: In heme protein–mediated AKI (HP-AKI), a senescence phenotype promptly occurs, and increased expression of p16 contributes to HP-AKI. Renal p16 expression is induced by hemoglobin, myoglobin, and heme and in renal epithelial cells exposed to heme . Impairing the binding or degradation of heme by hemopexin deficiency or heme oxygenase-1 deficiency, respectively, further upregulates p16.

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High-count monoclonal B-cell lymphocytosis (HCMBL) is a precursor condition to chronic lymphocytic leukemia (CLL). We have shown that among individuals with HCMBL, the CLL-International Prognostic Index (CLL-IPI) is prognostic for time-to-first therapy (TTFT). Little is known about the prognostic impact of somatically mutated genes among individuals with HCMBL.

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Background & Aims: The prevalence of non-alcoholic steatohepatitis (NASH)-driven hepatocellular carcinoma (HCC) is rising rapidly, yet its underlying mechanisms remain unclear. Herein, we aim to determine the role of hypoxia-inducible lipid droplet associated protein (HILPDA)/hypoxia-inducible gene 2 (HIG2), a selective inhibitor of intracellular lipolysis, in NASH-driven HCC.

Methods: The clinical significance of HILPDA was assessed in human NASH-driven HCC specimens by immunohistochemistry and transcriptomics analyses.

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TP53 aberrations, including mutations and deletion of 17p13, are important adverse prognostic markers in chronic lymphocytic leukemia (CLL) but are less studied in high count monoclonal B-cell lymphocytosis (HCMBL), an asymptomatic pre-malignant stage of CLL. Here we estimated the prevalence and impact of TP53 aberrations in 1,230 newly diagnosed treatment-naïve individuals (849 CLL, 381 HCMBL). We defined TP53 state as: wild-type (no TP53 mutations and normal 17p), single-hit (del(17p) or one TP53 mutation), or multi-hit (TP53 mutation and del(17p), TP53 mutation and loss of heterozygosity, or multiple TP53 mutations).

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Gene editing for the cure of inborn errors of metabolism (IEMs) has been limited by inefficiency of adult hepatocyte targeting. Here, we demonstrate that in utero CRISPR/Cas9-mediated gene editing in a mouse model of hereditary tyrosinemia type 1 provides stable cure of the disease. Following this, we performed an extensive gene expression analysis to explore the inherent characteristics of fetal/neonatal hepatocytes that make them more susceptible to efficient gene editing than adult hepatocytes.

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Context: SARS-CoV-2 infects the gastrointestinal tract and may be associated with symptoms that resemble diabetic gastroparesis. Why patients with diabetes who contract COVID-19 are more likely to have severe disease is unknown.

Objective: We aimed to compare the duodenal mucosal expression of SARS-CoV-2 and inflammation-related genes in diabetes gastroenteropathy (DGE), functional dyspepsia (FD), and healthy controls.

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Introduction: Serum α-fetoprotein (AFP), agglutinin-reactive AFP (AFP-L3), and des-γ-carboxy-pro-thrombin (DCP) are useful biomarkers of hepatocellular carcinoma (HCC). However, associations among molecular characteristics and serum biomarkers are unclear. We analyzed RNA expression and DNA variant data from The Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA-LIHC) to examine their associations with serum biomarker levels and clinical data.

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Background & Aims: In addition to gastric sensorimotor dysfunctions, functional dyspepsia (FD) is also variably associated with duodenal micro-inflammation and epithelial barrier dysfunction, the pathogenesis and clinical significance of which are unknown. Our hypothesis was that miRNAs and/or inflammation degrade epithelial barrier proteins, resulting in increased duodenal mucosal permeability in FD.

Methods: We compared the duodenal mucosal gene expression and miRNAs, in vivo permeability (lactulose-mannitol excretion between 0 and 60 and 60 and 120 minutes after saccharide ingestion), ex vivo assessments (transmucosal resistance, fluorescein isothiocyanate [FITC]-dextran flux, and basal ion transport), and duodenal histology (light and electron microscopy) in 40 patients with FD and 24 controls.

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Beta-catenin (CTNNB1) is commonly mutated in hepatocellular carcinoma (HCC). CTNNB1-mutated HCC has important clinical correlates, such as being immune cold and less likely to respond to immune checkpoint inhibitor therapies. It remains unclear, however, if they are a morphologically homogenous group of tumors.

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Background And Aims: Existing therapeutic approaches to treat cholangiocarcinoma (CCA) have limited effectiveness, prompting further study to develop therapies for CCA. We report a mechanistic role for the heparan sulfate editing enzyme sulfatase 2 (SULF2) in CCA pathogenesis.

Approach And Results: In silico analysis revealed elevated SULF2 expression in human CCA samples, occurring partly through gain of SULF2 copy number.

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The Hippo pathway effector Yes-associated protein (YAP) is localized to the nucleus and transcriptionally active in a number of tumor types, including a majority of human cholangiocarcinomas. YAP activity has been linked to chemotherapy resistance and has been shown to rescue KRAS and BRAF inhibition in RAS/RAF-driven cancers; however, the underlying mechanisms of YAP-mediated chemoresistance have yet to be elucidated. Herein, we report that the tyrosine phosphatase SHP2 directly regulates the activity of YAP by dephosphorylating pYAP even in the setting of RAS/RAF mutations, and that diminished SHP2 phosphatase activity is associated with chemoresistance in cholangiocarcinomas.

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Next-generation sequencing identified about 60 genes recurrently mutated in chronic lymphocytic leukemia (CLL). We examined the additive prognostic value of the total number of recurrently mutated CLL genes (i.e.

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A 16-year-old male was admitted to the paediatric ICU with acute onset of vomiting, somnolence, and chest pain, and electrocardiogram showing 2nd degree heart block after ingesting an Aleurites moluccana (Candlenut) seed as a herbal weight loss supplement. Electrocardiogram showed progressively worsening heart block with down-sloping of the ST segments, resembling digoxin toxicity. After 2 days of ICU observation, his symptoms began to improve and eventually resolved.

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Reduced BRCA1 expression causes homologous recombination (HR) repair defects in high-grade serous ovarian cancers (HGSOCs). Here, we demonstrate that BRCA1 is transcriptionally activated by a previously unknown function of ZC3H18. We show that ZC3H18 is a DNA-binding protein that interacts with an E2F site in the BRCA1 promoter where it facilitates recruitment of E2F4 to an adjacent E2F site to promote BRCA1 transcription.

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IL-33, an IL-1 family cytokine, is constitutively expressed in mucosal tissues and other organs in healthy humans and animals, and expression levels increase in inflammatory conditions. Although IL-33-mediated promotion of type 2 immune responses has been well established, a gap in our knowledge regarding the functional diversity of this pleiotropic cytokine remains. To address this gap, we developed a new IL-33 transgenic mouse model in which overexpression of full-length IL-33 is induced in lung epithelial cells under conditional control.

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Prostate cancer (PrCa) is highly heritable; 284 variants have been identified to date that are associated with increased prostate cancer risk, yet few genes contributing to its development are known. Expression quantitative trait loci (eQTL) studies link variants with affected genes, helping to determine how these variants might regulate gene expression and may influence prostate cancer risk. In the current study, we performed eQTL analysis on 471 normal prostate epithelium samples and 249 PrCa-risk variants in 196 risk loci, utilizing RNA sequencing transcriptome data based on ENSEMBL gene definition and genome-wide variant data.

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Background & Aims: The CCNE1 locus, which encodes cyclin E1, is amplified in many types of cancer cells and is activated in hepatocellular carcinomas (HCCs) from patients infected with hepatitis B virus or adeno-associated virus type 2, due to integration of the virus nearby. We investigated cell-cycle and oncogenic effects of cyclin E1 overexpression in tissues of mice.

Methods: We generated mice with doxycycline-inducible expression of Ccne1 (Ccne1 mice) and activated overexpression of cyclin E1 from age 3 weeks onward.

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Background: Mesenchymal stem cells (MSCs) perform paracrine functions by releasing extracellular vesicles (EVs) containing microRNA, mRNA, and proteins. We investigated the mRNA content of EVs in metabolic syndrome (MetS) and tested hypothesis that comorbidities interfere with the paracrine functionality of MSCs.

Methods: Mesenchymal stem cells were collected from swine abdominal adipose tissue after 16 weeks of a low- (Lean) or high-calorie (MetS) diet (n = 5 each).

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