Chemicals and Drugs Commons^™

Immunoactive Signatures Of Circulating Trna- And Rrna-Derived Rnas In Chronic Obstructive Pulmonary Disease, Megumi Shigematsu, Takuya Kawamura, Deepak Deshpande, Yohei Kirino

Computational Medicine Center Faculty Papers

Chronic obstructive pulmonary disease (COPD) is the most prevalent lung disease, and macrophages play a central role in the inflammatory response in COPD. We here report a comprehensive characterization of circulating short non-coding RNAs (sncRNAs) in plasma from patients with COPD. While circulating sncRNAs are increasingly recognized for their regulatory roles and biomarker potential in various diseases, the conventional RNA sequencing (RNA-seq) method cannot fully capture these circulating sncRNAs due to their heterogeneous terminal structures. By pre-treating the plasma RNAs with T4 polynucleotide kinase, which converts all RNAs to those with RNA-seq susceptible ends (5′-phosphate and 3′-hydroxyl), we comprehensively sequenced …

Design, Synthesis, And Evaluation Of Oleyl-Wrh Peptides For Sirna Delivery, Mrigank Shekhar Rai, Muhammad Imran Sajid, Jonathan Moreno, Keykavous Parang, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

Delivering nucleic acid therapeutics across cell membranes is a significant challenge. Cell-penetrating peptides (CPPs) containing arginine (R), tryptophan (W), and histidine (H) show promise for siRNA delivery. To improve siRNA delivery and silence a model STAT3 gene, we hypothesized that oleyl acylation to CPPs, specifically (WRH)n, would enhance STAT3 silencing efficiency in breast and ovarian cancer cells. Using Fmoc/tBu solid-phase peptide chemistry, we synthesized, purified, and characterized the oleyl-conjugated (WRH)n (n = 1–4) peptides. The peptide/siRNA complexes were non-cytotoxic at N/P 40 (~20 μM) against MDA-MB-231, MCF-7, SK-OV-3, and HEK-293 cells after 72 h incubation. All peptide/siRNA complexes showed serum …

Stress Granule Formation Helps To Mitigate Neurodegeneration, M. Rebecca Glineburg, Evrim Yildirim, Nicolas Gomez, Genesis Rodriguez, Jaclyn Pak, Xingli Li, Christopher Altheim, Jacob Waksmacki, Gerald M. Mcinerney, Sami J. Barmada, Peter K. Todd

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Cellular stress pathways that inhibit translation initiation lead to transient formation of cytoplasmic RNA/protein complexes known as stress granules. Many of the proteins found within stress granules and the dynamics of stress granule formation and dissolution are implicated in neurodegenerative disease. Whether stress granule formation is protective or harmful in neurodegenerative conditions is not known. To address this, we took advantage of the alphavirus protein nsP3, which selectively binds dimers of the central stress granule nucleator protein G3BP and markedly reduces stress granule formation without directly impacting the protein translational inhibitory pathways that trigger stress granule formation. In Drosophila and …

Computational Analysis Of O6-Methylated Guanine And Thioguanine Complexes, Kirsten Stinson, Michael Bowman

Lux et Fides: A Journal for Undergraduate Christian Scholars

DNA methylation occurring on the O⁶ position of guanine has been linked to the formation of cancer. DNA complexes with O⁶-methylated guanine have been studied experimentally, yet questions remain concerning the carcinogenic properties of O⁶-methylguanine. This present research explored the interaction between O⁶-methylguanine and its potential nucleobase pairs of cytosine and adenine in hopes of elucidating the mutagenic characteristics of O⁶-methylguanine. A variety of computational methods including Density Functional Theory (DFT), Symmetry Adapted Perturbation Theory (SAPT), Noncovalent Interaction (NCI) analysis, and Natural Bond Orbital (NBO) analysis were employed to comprehensively probe …

Hyperoxia-Induced Mir-195 Causes Bronchopulmonary Dysplasia In Neonatal Mice, Patrick Philpot, Fred Graumuller, Nicole Melchiorre, Varsha Prahaladan, Xander Takada, Srinarmadha Chandran, Melissa Guillermo, David Dickler, Zubair H Aghai, Pragnya Das, Vineet Bhandari

Department of Pediatrics Faculty Papers

Background: Exposure to hyperoxia is an important factor in the development of bronchopulmonary dysplasia (BPD) in preterm newborns. MicroRNAs (miRs) have been implicated in the pathogenesis of BPD and provide a potential therapeutic target. Methods: This study was conducted utilizing a postnatal animal model of experimental hyperoxia-induced murine BPD to investigate the expression and function of miR-195 as well as its molecular signaling targets within developing mouse lung tissue. Results: miR-195 expression levels increased in response to hyperoxia in male and female lungs, with the most significant elevation occurring in 40% O₂ (mild) and 60% O₂ (moderate) BPD. …

Repurposing Clinically Relevant Metabolic Inhibitor Drugs, Difluoromethylornithine (Dfmo) And Orlistat, For Gammaherpesvirus Replication, Lay Paw

Honors Projects

Viruses, including herpesviruses, contribute up to 15% of all human cancers. Murine gammaherpesvirus-68 (MHV-68), a pathogen commonly found in mice, is studied due to its shared homology with several human herpesviruses. Studies done in the Delgado lab via metabolomics analysis show MHV-68 infected cells increase host cell metabolism. Clinically relevant metabolic inhibitor drugs, ɑ-Difluoromethylornithine (DFMO) and Orlistat, respectively block polyamine and lipid production demonstrated a reduction in MHV-68 viral production. Repurposing clinically relevant drugs through the exploration of a different target shows great promise in reducing oncogenic viral titer.

The Diet As Medicine: The Power Of Lifestyle Habits To Control Autoimmune Diseases, Jacob Huber

University Honors College

Autoimmune diseases are a family of conditions that result from a malfunction in the immune system. The immune system mistakenly targets healthy tissue in the body, causing severe inflammation and pain in the part that it targets. While research of the diseases has come a long way, there are still a lot of questions unanswered about their origins and treatments. There are no known cures for any of the over 80 identified diseases, and treatment involves reducing the conditions activity to as low as possible. Still, autoimmune patients often live with constant levels of discomfort and impaired quality of life. …

Impact Of Fads Genotype On Polyunsaturated Fatty Acid Content In Human Milk Extracellular Vesicles: A Genetic Association Study, John J. Miklavcic, Natalie Paterson, Jennifer Hahn-Holbrook, Laura M. Glynn

Food Science Faculty Articles and Research

Background

Extracellular vesicles in human milk are critical in supporting newborn growth and development. Bioavailability of dietary extracellular vesicles may depend on the composition of membrane lipids. Single-nucleotide polymorphisms (SNPs) in the fatty acid desaturase gene cluster impact the content of long-chain polyunsaturated fatty acids in human milk phospholipids. This study investigated the relation between variation in FADS1 and FADS2 with the content of polyunsaturated fatty acids in extracellular vesicles from human milk.

Methods

Milk was obtained from a cohort of mothers (N = 70) at 2–4 weeks of lactation. SNPs in the FADS gene locus were determined using …

Single Dual-Specific Anti-Pd-L1/Tgf-Β Antibody Synergizes With Chemotherapy As Neoadjuvant Treatment For Pancreatic Ductal Adenocarcinoma: A Preclinical Experimental Study, Haoxiang Zhang, Jiaoshun Chen, Jianwei Bai, Jing Zhang, Shaoyi Huang, Liang Zeng, Pengfei Zhou, Qiang Shen, Tao Yin

School of Medicine Faculty Publications

AIMS: Chemotherapy resistance is an important cause of neoadjuvant therapy failure in pancreatic ductal adenocarcinoma (PDAC). BiTP is a single antibody that can simultaneously and dually target transforming growth factor-beta (TGF-β) and programmed cell death 1 ligand 1 (PD-L1). We attempted in this study to investigate the efficacy of BiTP in combination with first-line chemotherapy in PDAC. METHODS: Preclinical assessments of BiTP plus gemcitabine and nab-paclitaxel were completed through a resectable KPC mouse model (C57BL/6J). Spectral flow cytometry, tissue section staining, enzyme-linked immunosorbent assays, Counting Kit-8, transwell, and Western blot assays were used to investigate the synergistic effects. RESULTS: BiTP …

Modifying Peptide/Lipid-Associated Nucleic Acids (Planas) For Crispr/Cas9 Ribonucleoprotein Delivery, Abdulelah Alhazza, Parvin Mahdipoor, Ryley Hall, Arthur Manda, Sandeep Lohan, Keykavous Parang, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

With the first reports on the possibility of genome editing by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated protein (Cas)9 surfacing in 2005, the enthusiasm for protein silencing via nucleic acid delivery experienced a resurgence following a period of diminished enthusiasm due to challenges in delivering small interfering RNAs (siRNA), especially in vivo. However, delivering the components necessary for this approach into the nucleus is challenging, maybe even more than the cytoplasmic delivery of siRNA. We previously reported the birth of peptide/lipid-associated nucleic acids (PLANAs) for siRNA delivery. This project was designed to investigate the efficiency of …

Minrbase: A Comprehensive Database Of Nuclear- And Mitochondrial-Ribosomal-Rna-Derived Fragments (Rrfs), Venetia Pliatsika, Tess Cherlin, Phillipe Loher, Panagiotis Vlantis, Parth Nagarkar, Stepan Nersisyan, Isidore Rigoutsos

Computational Medicine Center Faculty Papers

We describe the Mitochondrial and Nuclear rRNA fragment database (MINRbase), a knowledge repository aimed at facilitating the study of ribosomal RNA-derived fragments (rRFs). MINRbase provides interactive access to the profiles of 130 238 expressed rRFs arising from the four human nuclear rRNAs (18S, 5.8S, 28S, 5S), two mitochondrial rRNAs (12S, 16S) or four spacers of 45S pre-rRNA. We compiled these profiles by analyzing 11 632 datasets, including the GEUVADIS and The Cancer Genome Atlas (TCGA) repositories. MINRbase offers a user-friendly interface that lets researchers issue complex queries based on one or more criteria, such as parental rRNA identity, nucleotide sequence, …

Chemical Synthesis Of Sensitive Dna, Komal Chillar

Dissertations, Master's Theses and Master's Reports

Over the past decades, researchers have tried various chemical methods to synthesize modified oligodeoxynucleotides (ODNs, i.e. short segments of DNAs). Traditional ODN synthesis methods require strong basic, and nucleophilic conditions for the deprotection and cleavage of the ODN from the solid support. However, the sensitive ODNs containing labile functionalities are vulnerable to such harsh conditions. Sensitive ODNs have a wide range of applications in research and pharmaceuticals. To synthesize sensitive ODNs, researchers devised different strategies but no practical methods have been developed. To overcome these challenges, we developed alkyl Dim alkyl Dmoc technology. This innovative technology uses weakly basic and …

Chemical Synthesis And Biological Application Of Sensitive Rna, Alexander T. Apostle

Dissertations, Master's Theses and Master's Reports

In the field of epigenetics - the dynamic collection of chemical modifications that overlay DNA/RNA - there is increasing interest in the potential for therapeutic and research-based utilization of the epitranscriptomics: those epigenetic modifications specific to RNA. Epitranscriptomics can give us a new approach to understanding and treating RNA viruses, like SARS-CoV-2. Given viruses are often found modified by human epitranscriptomic machinery, understanding how these modifications can modulate virulence is of high interest. We have shown that the N1-methyladensoine modification causes RNA synthesis termination in the SARS-CoV-2 replication complex, and thus may explain the differences in symptoms observed in individuals. …

Hybridization Kinetics Of Four-Way Junctions Localized On A Dna Scaffold, Katherine N. Taylor

Honors Undergraduate Theses

DNA computing is an ever-growing field with scientists trying to design structures that optimize logic gate communication to develop fast, biologically compatible, computational structures. We hypothesize that by using the principles of DNA computing, it is possible to design a DNA tile capable of studying localized DNA hybridization that can differentiate between oligonucleotides of different structural conformations. This includes synthetically manipulating DNA into a nanostructure that can perform Boolean logic functions to calculate the different rates of hybridization. To test our hypothesis, we designed a DNA Tile that incorporated a 4WJ using YES logic. Linear and hairpin single-stranded (ss) DNA …

Elucidating Mechanisms Of Enhanced Dsrna-Nanophytoglycogen Innate Immune Responses In Healthy Human Cells, Nicholas Jadaa

Theses and Dissertations (Comprehensive)

Immunostimulatory nucleic acids, such as long double-stranded RNA (ds)RNA, can stimulate innate immune responses in a non-sequence specific manner. These molecules are recognized by pattern-recognition receptors in the cytoplasm, endosome, and on the cell surface. Activation leads to the production of mediators of innate immune pathways, including type I interferon and proinflammatory cytokines. Although these receptors are present in all cells, their role in non-immune cells is often overlooked due to their lower level of responsiveness. Nanocarriers can enhance these nucleic acid-mediated responses, allowing for exploration of innate immune pathways in non-immune cells. Nanoparticles as carriers of nucleic acids can …

Advancing Small Molecule Therapies For Myotonic Dystrophy Type 1, Sawyer M. Hicks

Electronic Theses & Dissertations (2024 - present)

Myotonic dystrophy type 1 (DM1) is a multisystemic disorder caused by the expression of expanded CUG (CUG^exp) repeat RNA from the myotonic dystrophy protein kinase (DMPK) gene. This CUG^exp repeat RNA’s gain-of-function mechanism leads to the sequestration of muscleblind-like (MBNL) proteins, resulting in widespread alternative splicing dysregulation across tissues. Despite significant research, there are currently no approved therapeutics targeting the underlying causes of DM1. This dissertation explores the development and optimization of a novel class of small molecules, Modified Polycyclic Compounds (MPCs), designed to address splicing dysregulation in DM1. MPCs were designed from previously published …

Environmental Exposures And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

In recent years, research into air pollution has shown that exposure to certain components in air pollution, primarily PM2.5 can accelerate biological aging and thereby lead to increased susceptibility to multiple diseases. We hypothesize that prolonged exposure to air pollutants can result in premature aging leading to extensive tissue dysfunction and susceptibility to diseases. To examine this, we exposed mice to PM2.5 for 9, 15, and 21 days, then measured the telomere lengths, cellular senescence, and histone methylation patterns of multiple cell types. We found consistently increased telomere attrition, cellular senescence and advanced age-consistent histone methylation patterns in groups exposed …

Purification And Biochemical Characterization Of The Dna Binding Domain Of The Nitrogenase Transcriptional Activator Nifa From Gluconacetobacter Diazotrophicus, Heidi G. Standke, Lois Kim, Cedric P. Owens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

NifA is a σ⁵⁴ activator that turns on bacterial nitrogen fixation under reducing conditions and when fixed cellular nitrogen levels are low. The redox sensing mechanism in NifA is poorly understood. In α- and β-proteobacteria, redox sensing involves two pairs of Cys residues within and immediately following the protein’s central AAA⁺ domain. In this work, we examine if an additional Cys pair that is part of a C(X)5 C motif and located immediately upstream of the DNA binding domain of NifA from the α-proteobacterium Gluconacetobacter diazotrophicus (Gd) is involved in redox sensing. We hypothesize that the …

Mirnas Signature As Potential Biomarkers For Cervical Precancerous Lesions In Human Papillomavirus Positive Women, Martha I. González-Ramírez, Yurley T. Cardona, María C. Agudelo, Carolina López, Juan J. Florez-Acosta, Samuel Agudelo-Gamboa, Jone Garai, Li Li, Carlos A. Orozco-Castaño, Jovanny Zabaleta, Gloria I. Sánchez

School of Medicine Faculty Publications

Biomarkers to identify women at risk of cervical cancer among those with high-risk HPV infection (hrHPV+) are needed. Deregulated expression of microRNAs (miRNAs) contributes to hrHPV-induced cervical carcinogenesis. We aimed at identifying miRNAs with the capacity to distinguish high (CIN2+) and low (≤ CIN1) grade cervical lesions. We sequenced miRNA libraries from Formalin-Fixed Paraffin-Embedded (FFPE) tissues from women with CIN2+ (n = 10) and age-matched women with ≤ CIN1 (n = 10), randomly and retrospectively selected from a trial that followed women for 24 months after a hrHPV+ test at the screening visit. Five miRNAs differentially expressed were validated by …

Multi-Target Ligand-Guided Selection (Ligs) Against B-Cell Specific Antigens Expressed In A Single Lymphoma Cell Population, Nicole B. Williams

Dissertations, Theses, and Capstone Projects

Nucleic acid ligands called aptamers are single-stranded DNA or RNA molecules which fold into functional three-dimensional structures to facilitate their target binding with high affinity and specificity. The method used to generate aptamers is an in vitro process called Systematic Evolution of Ligands by Exponential enrichment (SELEX). A variant of SELEX, cell-SELEX has been used to select aptamers against cell-surface proteins in their native state. We recently introduced a novel method called Ligand-Guided Selection (LIGS) to identify aptamers against cell-surface markers. Herein, we expanded LIGS method into a multiplexing platform to partition multiple aptamers against B-cell-specific antigens, CD19 and CD20, …

Development Of Non-Viral Nano-Carriers For Gene Delivery And Covid-19 Vaccines, Zhongyu Li

Dissertations

Gene therapy is one of the most promising medical fields with the potential to effectively advance the treatment of difficult diseases by producing therapeutic proteins or repairing defective gene sequences. However, gene therapy presents severe challenges in delivery including renal clearance, phagocytosis, enzymatic degradation, protein absorption, and cellular internalization barriers, which have been barriers for translation into the clinic. Naked nucleic acids, with their intrinsic negative charge, electrostatically repulse the anionic cell membrane, preventing cellular uptake. Also, they are considered foreign genetic material when introduced into the body and are rapidly cleared by the reticuloendothelial system or degraded by nucleases, …

Microrna (Mirna) Complexity In Alzheimer’S Disease (Ad), Walter J. Lukiw

School of Medicine Faculty Publications

AD is a complex, progressive, age-related neurodegenerative disorder representing the most common cause of senile dementia and neurological dysfunction in our elderly domestic population. The widely observed heterogeneity of AD is a reflection of the complexity of the AD process itself and the altered molecular-genetic mechanisms operating in the diseased human brain and CNS. One of the key players in this complex regulation of gene expression in human pathological neurobiology are microRNAs (miRNAs) that, through their actions, shape the transcriptome of brain cells that normally associate with very high rates of genetic activity, gene transcription and messenger RNA (mRNA) generation. …

Synthesis, Characterization And Biological Evaluation Of Polyarginine Derived Bone-Targeting Peptides, Gina L. Antuono

Seton Hall University Dissertations and Theses (ETDs)

Osteoblast-targeting peptides in the treatment of bone disease is a new and novel approach to offering effective treatment of various cancers and can be used in bio-medical, medicinal chemistry and biotechnology applications. By targeting adhesion proteins produced by osteoblast cells, certain cancers which migrate and metastasize to the bone may be more effectively treated. An osteoblast-targeting peptide composed of Ser-Asp-Ser-Ser-Asp (SDSSD) which selectively binds to osteoblast cells via periostin has recently been identified. This peptide was functionalized with polyurethane, generating nanomicelles which encapsulated RNA for the therapeutic treatment of osteoporosis. This study has served as the basis for the research …

The Developing Effects Of Potassium Ferricyanide On Tetrahymena, Katelyn Coronell

Whittier Scholars Program

Potassium Cyanide is a highly toxic chemical asphyxiant that interferes with the body's ability to use oxygen, typically by directly affecting the body by ingestion, inhalation, skin contact, or eye contact(CDC, 2011). Due to its high toxicity, the main effect that leads to the downfall of the organism begins with the cessation of aerobic metabolism; it does this by cyanide binding to the ferric ions and inhibiting cytochrome oxidase within the mitochondria (Zhang, 2015). There are no physical dangers the substance causes. Although, there are many chemical dangers. If used at temperatures higher than 70℉ The substance may produce toxic …

Vitamin C Contributes To Epigenetic Regulation Of Genes Related To Diabetic Retinopathy In Retinal Endothelial Cells, Elizabeth L. Turner, Jonathon Reynolds, Walker Kay, Marianne Becnel, Matthew Conway, Alexander Kim, John A. Kriak, Kyle B. Bills, David W. Sant

Annual Research Symposium

No abstract provided.

Modified Linear Peptides Effectively Silence Stat-3 In Breast Cancer And Ovarian Cancer Cell Lines, Dindyal Mandal, Sandeep Lohan, Muhammad Imran Sajid, Abdulelah Alhazza, Rakesh Kumar Tiwari, Keykavous Parang, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

RNA interference (RNAi) has drawn enormous attention as a powerful tool because of its capability to interfere with mRNA and protein production. However, designing a safe and efficient delivery system in RNAi therapeutics remains challenging. Herein, we have designed and synthesized several linear peptides containing tryptophan (W) and arginine (R) residues separated by the β-alanine (βA) spacer and attached to a lipophilic fatty acyl chain, cholesterol, or PEG. The peptide backbone sequences were: Ac-C-βA-βA-W4-βA-βA-R4-CO-NH2 and Ac-K-βA-βA-W4-βA-βA-R4-CO-NH2, with only a difference in N-terminal amino acid. The cysteine side chain in the first sequence was used for the conjugation with PEG2000 and …

Endogenous Mirna-Based Innate-Immunity Against Sars-Cov-2 Invasion Of The Brain, Walter J. Lukiw, Aileen I. Pogue

School of Medicine Faculty Publications

The severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19, possesses an unusually large positive-sense, single-stranded viral RNA (ssvRNA) genome of about ~29,903 nucleotides (nt). In many respects, this ssvRNA resembles a very large, polycistronic messenger RNA (mRNA) possessing a 5′-methyl cap (m7GpppN), a 3′- and 5′-untranslated region (3′-UTR, 5′-UTR), and a poly-adenylated (poly-A+) tail. As such, the SARS-CoV-2 ssvRNA is susceptible to targeting by small non-coding RNA (sncRNA) and/or microRNA (miRNA), as well as neutralization and/or inhibition of its infectivity via the human body’s natural complement of about ~2650 miRNA species. Depending on host cell and tissue …

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh

UROP Posters

Human Immunodeficiency Virus (HIV) is a retrovirus that infects CD4+ T cell lymphocytes in humans, leading to the development of Acquired Immunodeficiency Syndrome (AIDS) if left untreated. While current treatment methods, including antiretroviral combination treatments, effectively limit HIV replication, HIV can evade these treatments due to its high mutation rate. Long-term antiretroviral treatment can also be toxic to patients, meaning patients would benefit from a new mechanism of HIV treatment. RNA interference (RNAi) is an antiviral pathway found in mammals, plants, and insects that involves a small-interfering RNA that is incorporated into a protein complex called the RNA-induced Silencing Complex …

Interactions Between Hiv And Opioids On Antiretroviral Accumulation, The Blood Brain Barrier, And The Inflammatory Response In The Brain., Kara Rademeyer

Theses and Dissertations

The complex mechanisms related to HIV infection, neurodegeneration, and chronic neuroinflammation collectively describe neuroHIV (Hauser et al. 2007; Chang et al. 2014; Smith et al. 2014). Specifically, opioid abuse, poor penetration of antiretroviral (ARV) drugs, chronic inflammation and neuronal injury/degeneration are all implicated in neuroHIV (Fantuzzi et al. 2003; Letendre et al. 2004; Verani et al. 2005; Duncan and Sattentau 2011; Hong and Banks 2015; Simoes and Justino 2015; Olivier et al. 2018; Murphy et al. 2019; Osborne et al. 2020). For the first time, we demonstrate that morphine, fentanyl, and methadone in vivo alter the brain accumulation of ARVs, …

Enhancing Dna-Damaging Therapy Through The Inhibition Of Dntp Synthesis Using A Synergistic Drug Combination To Treat Pancreatic Neuroendocrine Neoplasms, Jennifer Castle Md

Theses and Dissertations--Clinical and Translational Science

Despite clinical advances, pancreatic neuroendocrine neoplasms (pNEN) remain a difficult clinical entity to treat and can carry a poor prognosis. Systemic therapy is used to treat pNENs which are not amenable to surgical resection. Peptide receptor radionuclide therapy, a form of radiation therapy (RT) and cisplatin are two different forms of DNA-damaging therapy in current use to treat pNENs. However, their efficacy remains poor as single agents. This study aimed to increase the sensitivity of pNENs to the DNA-damaging agents, RT and cisplatin, by inhibiting deoxynucleotide triphosphate (dNTP) synthesis. Triapine, a ribonucleotide reductase inhibitor (RNRi), and ataxia telangiectasia and Rad3-related …