Cell and Developmental Biology Commons^™

Distinct Transcriptome Profiles Of Gag-Specific Cd8+ T Cells Temporally Correlated With The Protection Elicited By Sivδnef Live Attenuated Vaccine, Wuxun Lu, Yanmin Wu, Fangrui Ma, R. Paul Johnson, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The live attenuated vaccine (LAV) SIVmac239Δnef (SIVΔnef) confers the best protection among all the vaccine modalities tested in rhesus macaque model of HIV-1 infection. This vaccine has a unique feature of time-dependent protection: macaques are not protected at 3±5 weeks post vaccination (WPV), whereas immune protection emerges between 15 and 20 WPV. Although the exact mechanisms of the time-dependent protection remain incompletely understood, studies suggested that both cellular and humoral immunities contribute to this time-dependent protection. To further elucidate the mechanisms of protection induced by SIVΔnef, we longitudinally compared the global gene expression profiles of SIV Gag-CM9+ CD8+ (Gag-specific CD8+) …

Chloroviruses Have A Sweet Tooth, James L. Van Etten, Irina V. Agarkova, David D. Dunigan, Michela Tonetti, Cristina De Castro, Garry A. Duncan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large double-stranded DNA (dsDNA) viruses that infect certain isolates of chlorella-like green algae. They contain up to approximately 400 protein-encoding genes and 16 transfer RNA (tRNA) genes. This review summarizes the unexpected finding that many of the chlorovirus genes encode proteins involved in manipulating carbohydrates. These include enzymes involved in making extracellular polysaccharides, such as hyaluronan and chitin, enzymes that make nucleotide sugars, such as GDP-L-fucose and GDP-D-rhamnose and enzymes involved in the synthesis of glycans attached to the virus major capsid proteins. This latter process differs from that of all other glycoprotein containing viruses that traditionally use …

Tryptophan 375 Stabilizes The Outer-Domain Core Of Gp120 For Hiv Vaccine Immunogen Design, Duoyi Hu, Dane Bowder, Wenzhong Wei, Jesse Thompson, Mark A. Wilson, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

The outer-domain core of gp120 may serve as a better HIV vaccine immunogen than the full-length gp120 because of its greater stability and immunogenicity. In our previous report, we introduced two disulfide bonds to the outer-domain core of gp120 to fix its conformation into a CD4-bound state, which resulted in a significant increase in its immunogenicity when compared to the wild-type outer-domain core. In this report, to further improve the immunogenicity of the outer-domain core based immunogen, we have introduced a Tryptophan residue at gp120 amino acid sequence position 375 (375S/W). Our data from immunized guinea pigs indeed shows a …

Towards The Complete Proteinaceous Regulome Of Acinetobacter Baumannii, Leila G. Casella, Andy Weiss, Ernesto Pérez-Rueda, J Antonio Ibarra, Lindsey N. Shaw

Molecular Biosciences Faculty Publications

The emergence of Acinetobacter baumannii strains, with broad multidrug-resistance phenotypes and novel virulence factors unique to hypervirulent strains, presents a major threat to human health worldwide. Although a number of studies have described virulence-affecting entities for this organism, very few have identified regulatory elements controlling their expression. Previously, our group has documented the global identification and curation of regulatory RNAs in A. baumannii. As such, in the present study, we detail an extension of this work, the performance of an extensive bioinformatic analysis to identify regulatory proteins in the recently annotated genome of the highly virulent AB5075 strain. In so …

Genetic Analysis Of Serf Gene Function In Drosophila Melanogaster And Its Contribution To A Fly Model Of Spinal Muscular Atrophy, Swagata Ghosh

Theses and Dissertations--Biology

The Serf gene is evolutionarily highly conserved but its biological function is not known in any organism. In human, SERF1/H4F5 was first identified as a modifier of the disease Spinal Muscular Atrophy (SMA). SMA is caused by mutations in the Survival Motor Neuron 1(SMN1) gene leading to diminished levels of the Smn protein. More than 90% of patients with the most severe form of SMA have deletions that remove SERF1 as well as mutaions within SMN1. Hence, loss of Serf activity is hypothesized to exacerbate SMA disease progression. The primary motivation of this thesis was to test …

Dynamics Of Gene Networks In Cancer Research, Paul Scott

College of Graduate Studies: Theses & Dissertations

Cancer prevention treatments are being researched to see if an optimized treatment schedule would decrease the likelihood of a person being diagnosed with cancer. To do this we are looking at genes involved in the cell cycle and how they interact with one another. Through each gene expression during the life of a normal cell we get an understanding of the gene interactions and test these against those of a cancerous cell. First we construct a simplified network model of the normal gene network. Once we have this model we translate it into a transition matrix and force changes on …

The Role Of Klf1 In Regulating Γ-Globin Gene Repressors, Anna P. Kovilakath

Theses and Dissertations

Sickle cell disease and β-thalassemia affect millions of people worldwide. γ-globin is the fetal counterpart to the adult β-globin. Research has shown that affected patients with higher than normal γ-globin show less severe symptoms. Therefore, reversing or preventing the hemoglobin switch from γ- to β- globin is a promising avenue of research for treating these diseases. KLF1 is an erythroid transcription factor involved in hemoglobin switching. Herein, we show that KLF1 directly regulates the γ-globin repressor gene LRF in both the mouse and human systems. KLF1 may also directly activate γ-globin expression by binding the promoter. In human HUDEP-2 cells, …

In Vitro Three-Dimensional Skin Tissue Constructs, Tinashe Dereck Gombedza

Theses

Human skin provides fortification against peripheral threats which may compromise the integrity and health of the human body. Its presence as the largest human organ forms a protective barrier making it an effective first line of defence against pathogenic, chemical and physical damage. Tissue engineering technology has enabled the development of in vitro three-dimensional (3D) organotypic skin cultures in order to understand the skin's physiology and architecture. This advancement has enabled the use of 3D skin model platforms to study skin diseases and conditions as well as facilitate drug discovery, clinical research and cosmetic product development.

In this study, an …

Effects Of Posttranslational Modification Of Transcription Factor Gli-Similar 3 By Sumoylation On Insulin Transcription In Pancreatic Β Cells, Tyler M. Hoard

Murray State Theses and Dissertations

The ability to control blood glucose levels is a fundamental component of vertebrates. In these organisms, blood glucose homeostasis is achieved through a fine-tuned mechanism that largely involves the secretion of hormones from the endocrine pancreas into the bloodstream. These hormones include glucagon, which is secreted by the α cells of the pancreas and initiates the release of glucose into the bloodstream through gluconeogenesis in the liver, and insulin, which is secreted from the β cells and signals the uptake of excess blood glucose by the peripheral tissue. Gli-similar 3 (Glis3) is a transcription factor that has previously been shown …

Macropinosome Maturation Is A Clathrin Dependent Process In Bone Marrow Macrophages, Susmita Poudel

Electronic Theses and Dissertations

Macrophages nonspecifically take up extracellular fluids, solutes and macromolecules by macropinocytosis. Understanding the mechanisms of macropinosome maturation will inform the study of lipid uptake, viral entry, antigen processing and presentation, as well as regulation of cell growth. Colony stimulating factor-1 receptor (CSF-1R) is internalized by small vesicle endocytosis, trafficked to nascent macropinosomes and degraded. These CSF-1R positive macropinosomes mature through a sequence similar to endosomes, progressing from EEA1 and Rab5 to Rab7 positive vesicles before fusing with lysosomes. Here we report the assembly of clathrin on internalized macropinosomes shown both by live-cell microscopy of cells expressing clathrin light chain-yellow fluorescent …

Lipid-Laden Macrophages Downregulate Akt Phosphorylation And Metabolize Lipid Droplets Via Autophagy, Rifat Sultana

Electronic Theses and Dissertations

Macrophages contribute to plaque formation in atherosclerosis. Macrophages take up modified low-density lipoproteins and store excess cholesterol and triglycerides in lipid droplet organelles. Evidence of lipid-laden macrophages or “foam cells” is apparent on histology sections of diseased arteries, and this lipid-laden appearance can be recreated in cell culture upon exposure of cultured macrophages to acetylated LDL (Ac-LDL). Under nutrient stress, neutral lipids in lipid droplets are hydrolyzed by lipolysis, autophagy, or both. However, these processes are not well understood in macrophages. We created lipidladen macrophages by 24-h exposure to Ac-LDL and analyzed dynamics of lipid droplet metabolism following removal of …

Nanosecond Pulsed Electric Field Induced Changes In Cell Surface Charge Density, Diganta Dutta, Xavier-Lewis Palmer, Anthony Asmar, Michael Stacey, Shizhi Qian

Bioelectrics Publications

This study reports that the surface charge density changes in Jurkat cells with the application of single 60 nanosecond pulse electric fields, using atomic force microscopy. Using an atomic force microscope tip and Jurkat cells on silica in a 0.01 M KCl ionic concentration, we were able to measure the interfacial forces, while also predicting surface charge densities of both Jurkat cell and silica surfaces. The most important finding is that the pulsing conditions varyingly reduced the cells' surface charge density. This offers a novel way in which to examine cellular effects of pulsed electric fields that may lead to …

Vein Patterning During Juvenile Wing Development In Oncopeltus Fasciatus And Jadera Haematoloma, William R. Simmons

Honors Theses

Wings are a defining characteristic of all pterygote insects and are agreed to originate from a single common winged ancestor. However, essentially nothing is known about the molecular mechanisms that regulate wing development and patterning outside of Endopterygota, and the vast majority of this knowledge comes solely from Drosophila melanogaster. There is reason to suspect that the drastic developmental differences that exist between Endopterygota and Exopterygota have resulted in changes in the mechanisms, timings, or even genes that govern wing development. This study examined the roles of several genes known to be involved in D. melanogaster wing development and patterning …

Metabolic And Morphologic Shifts In Neuro2a Cells Cultured In Galactose Medium, Leah Welker

Masters Theses

It has been observed that highly-proliferating cells, such as cancer cells, rely mainly on glycolysis for ATP production, regardless of presence of oxygen. This effect, however, can be reversed by changing the main energy substrate in the medium from glucose to galactose. The oxidation of galactose in glycolysis yields less net ATP, presumably forcing the cell into OXPHOS. This has been established in many cell lines, including HeLA, HepG2, and skeletal muscle cells. As of yet, this has not been reproduced in neuronal cells. Using Neuro2a, a murine neuroblastoma cell line, this study exposes neuronal cells to galactose medium, and …

Progesterone Receptor And Prostaglandins Mediate Luteinizing Hormone-Induced Changes In Messenger Rnas For Adamts Proteases In Theca Cells Of Bovine Periovulatory Follicles, Erin L. Willis, Phillip J. Bridges, Joanne E. Fortune

Animal and Food Sciences Faculty Publications

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non‐rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin‐releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle‐stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post‐GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, ‐2, …

Differential Activity And Content Of High-Affinity Glutamate Transporters, Content Of Their Regulatory Proteins, And Capacity For Glutamine And Glutathione Synthesis In Tissues Of Finished Versus Growing Steers, Jing Huang

Theses and Dissertations--Animal and Food Sciences

Improvement of feeding regimens for production animals has been hindered by a lack of fundamental knowledge about how the capacity to regulate nutrient absorption across cell membranes affects the function of nutrient metabolizing enzymes. The objective is to determine if the activities and protein content of system X^-_AG glutamate transporter, its regulatory protein (GTRAP3-18 and ARL6IP1), glutamine synthetase (GS) and glutathione (GSH) content, changes in liver (Experiment 1), longissimus dorsi (LM) and subcutaneous adipose tissue (SF) (Experiment 2) as beef steers transitioned from predominantly-lean (growing) to -lipid (finished) tissue accretion phases. In liver (Experiment 1), system X^{- …}

Salvianolic Acid B For Pulmonary Delivery Towards Reversal Of Emphysema, Sneha Dhapare

Theses and Dissertations

A new pathobiologic hypothesis has recently emerged that the alveolar structural destruction and loss in emphysema are caused by the deficiency of vascular endothelial growth factor (VEGF). Therefore, this project hypothesized that such pathobiologic VEGF deficiency of emphysematous lungs can be recovered with a natural caffeic acid tetramer, salvianolic acid B (SalB), through activation of signal transducer and activator of transcription 3 (STAT3), so that emphysema can be reversed as a result of inhibition of induced cell death, stimulation of cell proliferation and migration, and promotion of stem cell recruitment to the lungs.

SalB was first shown to be potently …

The Role Of N-Myc Downstream Regulated Gene 1 In Breast Cancer Lipid Metabolism, Christopher James Sevinsky

Legacy Theses & Dissertations (2009 - 2024)

Altered carbohydrate and lipid metabolism are increasingly well characterized hallmarks of aggressive breast cancers. While aerobic glycolysis, or “the Warburg effect”, is a well-established metabolic adaptation exploited by tumor cells, the understanding of unique aspects of cancer lipid metabolism lags behind. This is especially true regarding the coordination of complex lipid synthesis and trafficking pathways, which remains poorly understood. N-Myc Downstream Regulated Gene1 (NDRG1) is overexpressed in many solid tumors, but its function is unclear. The importance of NDRG1 is best exemplified by the effect of null mutations on human physiology: inactivating mutations give rise to the severe autosomal recessive …

Understanding The Genotoxicity Of Silver Nanoparticles And The Chemoprevention Of Pomegranate Extract, Sameera Nallanthighal

Legacy Theses & Dissertations (2009 - 2024)

The use of silver nanoparticles (AgNPs) in a wide variety of consumer products (i.e. toothpastes, food containers, dietary supplements and garments) for their antimicrobial properties can lead to potential oral exposure in humans. To enhance their stability, AgNPs are coated with capping agents such as citrate and polyvinylpyrrolidone (PVP). Despite the lack of significant general toxicity based on hematology, blood chemistry and histology evaluations, the potential genotoxic effects of AgNPs cannot be ruled out and have to be addressed. Studies examining the genotoxic risks of AgNPs are needed because genotoxicity is a strong indicator of cancer risk. Here we examined …

Detoxification Of Mitochondrial Oxidants And Apoptotic Signaling Are Facilitated By Thioredoxin-2 And Peroxiredoxin-3 During Hyperoxic Injury, Benjamin J. Forred, Darwin R. Daugaard, Brianna K. Titus, Ryan R. Wood, Miranda J. Floen, Michelle L. Booze, Peter F. Vitiello

School of Veterinary and Biomedical Sciences: Faculty Publications

Mitochondria play a fundamental role in the regulation of cell death during accumulation of oxidants. High concentrations of atmospheric oxygen (hyperoxia), used clinically to treat tissue hypoxia in premature newborns, is known to elicit oxidative stress and mitochondrial injury to pulmonary epithelial cells. A consequence of oxidative stress in mitochondria is the accumulation of peroxides which are detoxified by the dedicated mitochondrial thioredoxin system. This system is comprised of the oxidoreductase activities of peroxiredoxin-3 (Prx3), thioredoxin-2 (Trx2), and thioredoxin reductase-2 (TrxR2). The goal of this study was to understand the role of the mitochondrial thioredoxin system and mitochondrial injuries during …

Maternal Inflammation At Mid-Gestation In Pregnant Rats Impairs Fetal Muscle Growth And Development At Term, C. N. Cadaret, K. A. Beede, E. M. Merrick, T. L. Barnes, J. D. Loy, D. T. Yates

School of Veterinary and Biomedical Sciences: Faculty Publications

Intrauterine growth restriction (IUGR) is a leading cause of perinatal morbidity and mortality. Low birth weight resulting from preterm birth and/or IUGR is an underlying factor in 60–80% of perinatal death worldwide, and is particularly common in developing countries (UNICEF, 2008). Furthermore, studies have linked IUGR and the associated fetal malnutrition to increased incidence of metabolic syndrome in adult life (Barker et al., 1993; Godfrey and Barker, 2000). The “thrifty phenotype hypothesis” developed by David Barker (Hales et al., 1991) states that IUGR-associated fetal malnutrition forces the fetus to spare nutrients by altering tissue-specific metabolism in order to survive. In …

A Parapoxviral Virion Protein Targets The Retinoblastoma Protein To Inhibit Nf-Κb Signaling, Ponnuraj Nagendraprabhu, Sushil Khatiwada, Sabal Chaulagain, Gustavo A. Delhon, Daniel L. Rock

School of Veterinary and Biomedical Sciences: Faculty Publications

Poxviruses have evolved multiple strategies to subvert signaling by Nuclear Factor κB (NF-κB), a crucial regulator of host innate immune responses. Here, we describe an orf virus (ORFV) virion-associated protein, ORFV119, which inhibits NF-κB signaling very early in infection (≤30 min post infection). ORFV119 NF-κB inhibitory activity was found unimpaired upon translation inhibition, suggesting that virion ORFV119 alone is responsible for early interference in signaling. A C-terminal LxCxE motif in ORFV119 enabled the protein to interact with the retinoblastoma protein (pRb) a multifunctional protein best known for its tumor suppressor activity. Notably, experiments using a recombinant virus containing an ORFV119 …

Characterization Of A New Chlorovirus Type With Permissive And Non-Permissive Features On Phylogenetically Related Algal Strains, Cristian F. Quispe, Ahmed Esmael, Olivia Sonderman, Michelle Mcquinn, Irina Agarkova, Mohammed Battah, Garry A. Duncan, David D. Dunigan, Timothy P. L. Smith, Cristina Decastro, Immacolata Speciale, Fangrui Ma, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

A previous report indicated that prototype chlorovirus PBCV-1 replicated in two Chlorella variabilis algal strains, NC64A and Syngen 2-3, that are ex-endosymbionts isolated from the protozoan Paramecium bursaria. Surprisingly, plaque-forming viruses on Syngen 2-3 lawns were often higher than on NC64A lawns from indigenous water samples. These differences led to the discovery of viruses that exclusively replicate in Syngen 2-3 cells, named Only Syngen (OSy) viruses. OSy-NE5, the prototype virus for the proposed new species, had a linear dsDNA genome of 327 kb with 44-nucleotide-long, incompletely base-paired, covalently closed hairpin ends. Each hairpin structure was followed by an identical …

Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel

Wayne State University Dissertations

Clinically available treatments are insufficient to achieve full functional recovery in large (>3cm) peripheral nerve injuries (PNI). The objectives in this thesis were 1) to study often overlooked elements of intrinsic PNI repair including release of inhibitory CSPGs and post-injury responses of inflammatory macrophages and dedifferentiated Schwann cells; 2) to create biomaterial scaf-folds featuring topographical and adhesive cues to enhance neurite outgrowth; and 3) to test the ability of those cues to direct macrophages and Schwann cells towards a pro-regenerative phe-notype. It is hypothesized that recapitulating the positive and negative cues of the PNI microenvi-ronment can better improve regeneration. …

Pioglitazone, Neet Family Proteins, And Galactose Modulation Of Liver Cell Bioenergetics, David F. Grimm

Undergraduate Honors Theses

MitoNEET was discovered through interactions with a labeled and photoactive derivative of pioglitazone (pio), a drug used to increase peripheral insulin sensitivity. Its unique coordination of a [2Fe-2S] cluster by three cysteine residues (Cys-72, Cys-74, and Cys-83) and one histidine (His-87) gives this cluster both stability and the ability to be donated to acceptor proteins. These qualities allow mitoNEET to participate in a diversity of biological functions. Functions of mitoNEET and the consequences of pioglitazone (pio) treatment in human hepatocellular carcinoma (HepG2) cells cultured in glucose or galactose-based medium were examined by respiration and proliferation studies. Pio treatment decreased complex …

The Localization And Function Of Novel Tetrahymena Thermophila Cytoskeletal Genes Bbc29 And Bbc39, Emily K. Moore, Nicole C. Zanolli

Undergraduate Research Symposium Posters

Ciliary function is known to play an important role in many human conditions, including chronic sinus and pulmonary diseases and problems with infertility. Cilia are cytoskeletal structures that protrude from the cell body to facilitate movement. Ciliary structure is conserved throughout eukaryotes, from unicellular to multicellular organisms, including humans. A clear understanding the proteins that compose cilia and how they interact with one another will increase our knowledge about important cytoskeletal elements. Because cilia are difficult to study in multicellular organisms, the unicellular eukaryote Tetrahymena thermophila serves as a useful model for the study of cytoskeletal genes, due to their …

Identifying The Effects Of A Human Dynein Mutation On Gfp-Rab7 Axonal Transport In Embryonic Mouse Neurons, Natalie E. Wilson

Honors Undergraduate Theses

The first dynein mutation found in humans that caused disease was a cytoplasmic dynein 1 heavy chain (DYNC1H1 in humans) p.His306Arg mutation, first described by Weedon et al. in 2011. This mutation caused Charcot-Marie-Tooth (CMT) subtype 2O. CMT has a prevalence of approximately 1 in 2500 people, making it the most common hereditary neuromuscular disorder. Cytoplasmic dynein 1 is used by eukaryotic cells for minus-end directed microtubule-based transport of cargo. One such cargo is Rab7, a late endosomal marker. The purpose of this study is to identify the effects of this mutation on the transport of GFP-tagged Rab7 cargo in …

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …

Chaperonin Containing Tcp1 (Cct) As A Target For Cancer Therapy, Ana Carr

Electronic Theses and Dissertations

Treatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the CCT2 subunit is highly expressed in breast cancer and could be therapeutically targeted. To determine whether CCT is a marker of disease progression in other cancers, we analyzed CCT2 gene …

Novel Cytokine Signaling And Molecular Therapeutic Strategy In Pancreatic Cancer, Sarah Gitto

Electronic Theses and Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is highly chemo-resistant and has a five year survival rate of < 8%. Risk factors of pancreatic cancer, such as chronic pancreatitis, help to elicit a pro-tumor immune response, and highly fibrotic environment that promotes tumorigenesis. To study how chronic pancreatitis promotes cancer initiation, traditional KRasG12D mice and double mutant Akt1Myr/KrasG12D mice were used to model microenvironment changes. Akt1Myr/KrasG12D mice were more susceptible to chronic tissue damage, accelerated tumor development and metastatic disease. These mice exhibited histological changes consistent with immune cell privilege, where M2 macrophages and non-cytotoxic eosinophils were co-localized with fibrotic regions. IL-5 expression was up regulated in pancreatic cells undergoing acinar to ductal metaplasia and then diminished in advanced lesions. Tumor cells treated with IL-5 exhibit increased migration and activation through STAT5 signaling. Collectively, the results suggest that eosinophils, which are responsive to IL-5, are key mediators in the pancreatic environment subjected to chronic inflammation and injury. Current therapeutics fall short in increasing patient survival. There remains an urgent need for innovative treatments and thus we tested difluoromethylornithine (DFMO) in combination with a novel polyamine transport inhibitor, Trimer44NMe, against Gemcitabine-resistant PDAC cells. Prior clinical failures when targeting polyamine biosynthesis with DFMO monotherapy may be due to tumor escape via an undefined polyamine transport system. In pancreatic tumor cells DFMO alone and with Trimer44NMe significantly reduced PDAC cell viability by inducing apoptosis or cell cycle arrest. In vivo orthotopic PDAC growth with DFMO treatment resulted in decreased c-Myc expression, a readout of polyamine pathway dysfunction. Moreover, dual inhibition significantly prolonged survival of tumor-bearing mice, and increased M1 macrophage infiltration and reduced FoxP3 expression. Collectively, these studies demonstrate that targeting polyamine pathways in PDAC is a promising immunomodulating therapy that increases survival.