Biological Phenomena, Cell Phenomena, and Immunity Commons^™

Activation Of Crtc2/Creb1 In Skeletal Muscle Enhances Weight Loss During Intermittent Fasting, Nelson E Bruno, Jerome C Nwachukwu, David C Hughes, Sathish Srinivasan, Richard Hawkins, David Sturgill, Gordon L Hager, Stephen Hurst, Shey-Shing Sheu, Sue C Bodine, Michael D Conkright, Kendall W Nettles

Department of Medicine Faculty Papers

The Creb-Regulated Transcriptional Coactivator (Crtc) family of transcriptional coregulators drive Creb1-mediated transcription effects on metabolism in many tissues, but the in vivo effects of Crtc2/Creb1 transcription on skeletal muscle metabolism are not known. Skeletal muscle-specific overexpression of Crtc2 (Crtc2 mice) induced greater mitochondrial activity, metabolic flux capacity for both carbohydrates and fats, improved glucose tolerance and insulin sensitivity, and increased oxidative capacity, supported by upregulation of key metabolic genes. Crtc2 overexpression led to greater weight loss during alternate day fasting (ADF), selective loss of fat rather than lean mass, maintenance of higher energy expenditure during the fast and reduced binge-eating …

Immune Phenotype Of Patients With Stage Iv Metastatic Inflammatory Breast Cancer., Sandra V Fernandez, Alexander W Macfarlane, Mowafaq Jillab, Maria F Arisi, Jennifer Yearley, Lakshmanan Annamalai, Yulan Gong, Kathy Q Cai, R Katherine Alpaugh, Massimo Cristofanilli, Kerry S Campbell

Student Papers, Posters & Projects

BACKGROUND: Inflammatory breast cancer (IBC) is a rare but aggressive carcinoma characterized by severe erythema and edema of the breast, with many patients presenting in advanced metastatic disease. The "inflammatory" nature is not due to classic immune-mediated inflammation, but instead results from tumor-mediated blockage of dermal lymphatic ducts. Previous work has shown that expression of PD-L1 on tumor cells can suppress T cell activation in triple-negative (TN) non-IBC breast cancer. In the present work, we investigated immune parameters in peripheral blood of metastatic IBC patients to determine whether cellular components of the immune system are altered, thereby contributing to pathogenesis …

Cyclin D1 Integrates G9a-Mediated Histone Methylation., Zhiping Li, Xuanmao Jiao, Gabriele Di Sante, Adam Ertel, Mathew C. Casimiro, Min Wang, Sanjay Katiyar, Xiaoming Ju, D. V. Klopfenstein, Aydin Tozeren, William Dampier, Iouri Chepelev, Albert Jeltsch, Richard G. Pestell

Department of Cancer Biology Faculty Papers

Lysine methylation of histones and non-histone substrates by the SET domain containing protein lysine methyltransferase (KMT) G9a/EHMT2 governs transcription contributing to apoptosis, aberrant cell growth, and pluripotency. The positioning of chromosomes within the nuclear three-dimensional space involves interactions between nuclear lamina (NL) and the lamina-associated domains (LAD). Contact of individual LADs with the NL are dependent upon H3K9me2 introduced by G9a. The mechanisms governing the recruitment of G9a to distinct subcellular sites, into chromatin or to LAD, is not known. The cyclin D1 gene product encodes the regulatory subunit of the holoenzyme that phosphorylates pRB and NRF1 thereby governing cell-cycle …

Potential Role Of Csf Cytokine Profiles In Discriminating Infectious From Non-Infectious Cns Disorders., Danielle Fortuna, D. Craig Hooper, Amity L. Roberts, Larry A. Harshyne, Michelle Nagurney, Mark T. Curtis

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Current laboratory testing of cerebrospinal fluid (CSF) does not consistently discriminate between different central nervous system (CNS) disease states. Rapidly distinguishing CNS infections from other brain and spinal cord disorders that share a similar clinical presentation is critical. New approaches focusing on aspects of disease biology, such as immune response profiles that can have stimulus-specific attributes, may be helpful. We undertook this preliminary proof-of-concept study using multiplex ELISA to measure CSF cytokine levels in various CNS disorders (infections, autoimmune/demyelinating diseases, lymphomas, and gliomas) to determine the potential utility of cytokine patterns in differentiating CNS infections from other CNS diseases. Both …

Saturation Mutagenesis Reveals Manifold Determinants Of Exon Definition., Shengdong Ke, Vincent Anquetil, Jorge Rojas Zamalloa, Alisha Maity, Anthony Yang, Mauricio A. Arias, Sergey Kalachikov, James J Russo, Jingyue Ju, Lawrence A. Chasin

Student Papers, Posters & Projects

To illuminate the extent and roles of exonic sequences in the splicing of human RNA transcripts, we conducted saturation mutagenesis of a 51-nt internal exon in a three-exon minigene. All possible single and tandem dinucleotide substitutions were surveyed. Using high-throughput genetics, 5560 minigene molecules were assayed for splicing in human HEK293 cells. Up to 70% of mutations produced substantial (greater than twofold) phenotypes of either increased or decreased splicing. Of all predicted secondary structural elements, only a single 15-nt stem-loop showed a strong correlation with splicing, acting negatively. The in vitro formation of exon-protein complexes between the mutant molecules and …

A Simple And Accurate Rule-Based Modeling Framework For Simulation Of Autocrine/Paracrine Stimulation Of Glioblastoma Cell Motility And Proliferation By L1cam In 2-D Culture., Justin Caccavale, David Fiumara, Michael Stapf, Liedeke Sweitzer, Hannah J. Anderson, Jonathan Gorky, Prasad Dhurjati, Deni S. Galileo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Glioblastoma multiforme (GBM) is a devastating brain cancer for which there is no known cure. Its malignancy is due to rapid cell division along with high motility and invasiveness of cells into the brain tissue. Simple 2-dimensional laboratory assays (e.g., a scratch assay) commonly are used to measure the effects of various experimental perturbations, such as treatment with chemical inhibitors. Several mathematical models have been developed to aid the understanding of the motile behavior and proliferation of GBM cells. However, many are mathematically complicated, look at multiple interdependent phenomena, and/or use modeling software not freely available to the research …

Mdm2 Is Required For Survival And Growth Of P53-Deficient Cancer Cells., Kyle P Feeley, Clare M. Adams, Ramkrishna Mitra, Christine M. Eischen

Department of Cancer Biology Faculty Papers

p53 deletion prevents the embryonic lethality of normal tissues lacking Mdm2, suggesting that cells can survive without Mdm2 if p53 is also absent. Here we report evidence challenging this view, with implications for therapeutically targeting Mdm2. Deletion of Mdm2 in T-cell lymphomas or sarcomas lacking p53 induced apoptosis and G₂ cell-cycle arrest, prolonging survival of mice with these tumors. p53^-/- fibroblasts showed similar results, indicating that the effects of Mdm2 loss extend to pre-malignant cells. Mdm2 deletion in p53^-/- cells upregulated p53 transcriptional target genes that induce apoptosis and cell-cycle arrest. Mdm2 deletion also increased levels of …

Identification Of Early Gene Expression Changes In Primary Cultured Neurons Treated With Topoisomerase I Poisons., Sharyn L. Rossi, Casey J. Lumpkin, Ashlee W. Harris, Jennifer Holbrook, Cinsley Gentillon, Suzanne M. Mccahan, Wenlan Wang, Matthew E.R. Butchbach

Department of Pediatrics Faculty Papers

Topoisomerase 1 (TOP1) poisons like camptothecin (CPT) are currently used in cancer chemotherapy but these compounds can have damaging, off-target effects on neurons leading to cognitive, sensory and motor deficits. To understand the molecular basis for the enhanced sensitivity of neurons to CPT, we examined the effects of compounds that inhibit TOP1-CPT, actinomycin D (ActD) and β-lapachone (β-Lap)-on primary cultured rat motor (MN) and cortical (CN) neurons as well as fibroblasts. Neuronal cells expressed higher levels of Top1 mRNA than fibroblasts but transcript levels are reduced in all cell types after treatment with CPT. Microarray analysis was performed to identify …

Mitochondrial Akt Regulation Of Hypoxic Tumor Reprogramming., Young Chan Chae, Valentina Vaira, M. Cecilia Caino, Hsin-Yao Tang, Jae Ho Seo, Andrew V. Kossenkov, Luisa Ottobrini, Cristina Martelli, Giovanni Lucignani, Irene Bertolini, Marco Locatelli, Kelly G. Bryant, Jagadish C. Ghosh, Sofia Lisanti, Bonsu Ku, Silvano Bosari, Lucia R. Languino, David W. Speicher, Dario C. Altieri

Department of Cancer Biology Faculty Papers

Hypoxia is a universal driver of aggressive tumor behavior, but the underlying mechanisms are not completely understood. Using a phosphoproteomics screen, we now show that active Akt accumulates in the mitochondria during hypoxia and phosphorylates pyruvate dehydrogenase kinase 1 (PDK1) on Thr346 to inactivate the pyruvate dehydrogenase complex. In turn, this pathway switches tumor metabolism toward glycolysis, antagonizes apoptosis and autophagy, dampens oxidative stress, and maintains tumor cell proliferation in the face of severe hypoxia. Mitochondrial Akt-PDK1 signaling correlates with unfavorable prognostic markers and shorter survival in glioma patients and may provide an "actionable" therapeutic target in cancer.

Dna-Pkcs-Mediated Transcriptional Regulation Drives Prostate Cancer Progression And Metastasis., Jonathan F Goodwin, Vishal Kothari, Justin M Drake, Shuang Zhao, Emanuela Dylgjeri, Jeffry L. Dean, Matthew J. Schiewer, Christopher Mcnair, Jennifer K. Jones, Alvaro Aytes, Michael S. Magee, Adam E. Snook, Ziqi Zhu, Robert Den, Ruth C. Birbe, Leonard G. Gomella, Nicholas A. Graham, Ajay A. Vashisht, James A. Wohlschlegel, Thomas G. Graeber, R. Jeffrey Karnes, Mandeep Takhar, Elai Davicioni, Scott A. Tomlins, Cory Abate-Shen, Nima Sharifi, Owen N. Witte, Felix Y. Feng, Karen E. Knudsen

Department of Cancer Biology Faculty Papers

Emerging evidence demonstrates that the DNA repair kinase DNA-PKcs exerts divergent roles in transcriptional regulation of unsolved consequence. Here, in vitro and in vivo interrogation demonstrate that DNA-PKcs functions as a selective modulator of transcriptional networks that induce cell migration, invasion, and metastasis. Accordingly, suppression of DNA-PKcs inhibits tumor metastases. Clinical assessment revealed that DNA-PKcs is significantly elevated in advanced disease and independently predicts for metastases, recurrence, and reduced overall survival. Further investigation demonstrated that DNA-PKcs in advanced tumors is highly activated, independent of DNA damage indicators. Combined, these findings reveal unexpected DNA-PKcs functions, identify DNA-PKcs as a potent driver …

Epitope Characterization Of Sero-Specific Monoclonal Antibody To Clostridium Botulinum Neurotoxin Type A., Cindi R Corbett, Erin Ballegeer, Kelly A Weedmark, M D Elias, Fetweh H Al-Saleem, Denise M Ancharski, Lance L Simpson, Jody D Berry

Department of Medicine Faculty Papers

Botulinum neurotoxins (BoNTs) are extremely potent toxins that can contaminate foods and are a public health concern. Anti-BoNT antibodies have been described that are capable of detecting BoNTs; however there still exists a need for accurate and sensitive detection capabilities for BoNTs. Herein, we describe the characterization of a panel of eight monoclonal antibodies (MAbs) generated to the non-toxic receptor-binding domain of BoNT/A (H(C)50/A) developed using a high-throughput screening approach. In two independent hybridoma fusions, two groups of four IgG MAbs were developed against recombinant H(C)50/A. Of these eight, only a single MAb, F90G5-3, bound to the whole BoNT/A protein …

Acetate Causes Alcohol Hangover Headache In Rats., Christina R Maxwell, Rebecca Jay Spangenberg, Jan B Hoek, Stephen D Silberstein, Michael L Oshinsky

Department of Neurology Faculty Papers

BACKGROUND: The mechanism of veisalgia cephalgia or hangover headache is unknown. Despite a lack of mechanistic studies, there are a number of theories positing congeners, dehydration, or the ethanol metabolite acetaldehyde as causes of hangover headache.

METHODS: We used a chronic headache model to examine how pure ethanol produces increased sensitivity for nociceptive behaviors in normally hydrated rats.

RESULTS: Ethanol initially decreased sensitivity to mechanical stimuli on the face (analgesia), followed 4 to 6 hours later by inflammatory pain. Inhibiting alcohol dehydrogenase extended the analgesia whereas inhibiting aldehyde dehydrogenase decreased analgesia. Neither treatment had nociceptive effects. Direct administration of acetate …

Pp32 (Anp32a) Expression Inhibits Pancreatic Cancer Cell Growth And Induces Gemcitabine Resistance By Disrupting Hur Binding To Mrnas., Timothy K Williams, Christina L Costantino, Nikolai A Bildzukewicz, Nathan G Richards, David W Rittenhouse, Lisa Einstein, Joseph A Cozzitorto, Judith C Keen, Abhijit Dasgupta, Myriam Gorospe, Gregory E Gonye, Charles J Yeo, Agnieszka K Witkiewicz, Jonathan R Brody

Department of Surgery Faculty Papers

The expression of protein phosphatase 32 (PP32, ANP32A) is low in poorly differentiated pancreatic cancers and is linked to the levels of HuR (ELAV1), a predictive marker for gemcitabine response. In pancreatic cancer cells, exogenous overexpression of pp32 inhibited cell growth, supporting its long-recognized role as a tumor suppressor in pancreatic cancer. In chemotherapeutic sensitivity screening assays, cells overexpressing pp32 were selectively resistant to the nucleoside analogs gemcitabine and cytarabine (ARA-C), but were sensitized to 5-fluorouracil; conversely, silencing pp32 in pancreatic cancer cells enhanced gemcitabine sensitivity. The cytoplasmic levels of pp32 increased after cancer cells are treated with certain stressors, …

Asymmetric Deactivation Of Hiv-1 Gp41 Following Fusion Inhibitor Binding., Kristen M Kahle, H Kirby Steger, Michael J Root

Department of Biochemistry and Molecular Biology Faculty Papers

Both equilibrium and nonequilibrium factors influence the efficacy of pharmaceutical agents that target intermediate states of biochemical reactions. We explored the intermediate state inhibition of gp41, part of the HIV-1 envelope glycoprotein complex (Env) that promotes viral entry through membrane fusion. This process involves a series of gp41 conformational changes coordinated by Env interactions with cellular CD4 and a chemokine receptor. In a kinetic window between CD4 binding and membrane fusion, the N- and C-terminal regions of the gp41 ectodomain become transiently susceptible to inhibitors that disrupt Env structural transitions. In this study, we sought to identify kinetic parameters that …

Positional Information Generated By Spatially Distributed Signaling Cascades., Javier Muñoz-García, Zoltan Neufeld, Boris N Kholodenko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The temporal and stationary behavior of protein modification cascades has been extensively studied, yet little is known about the spatial aspects of signal propagation. We have previously shown that the spatial separation of opposing enzymes, such as a kinase and a phosphatase, creates signaling activity gradients. Here we show under what conditions signals stall in the space or robustly propagate through spatially distributed signaling cascades. Robust signal propagation results in activity gradients with long plateaus, which abruptly decay at successive spatial locations. We derive an approximate analytical solution that relates the maximal amplitude and propagation length of each activation profile …

Stat5 Regulation Of Bcl10 Parallels Constitutive Nfkappab Activation In Lymphoid Tumor Cells., Zsuzsanna S Nagy, Matthew J Lebaron, Jeremy A Ross, Abhisek Mitra, Hallgeir Rui, Robert A Kirken

Department of Cancer Biology Faculty Papers

BACKGROUND: Signal Transducer and Activator of Transcription 5 A and B (STAT5) are key survival factors in cells of the lymphoid lineage. Identification of novel, tissue-specific STAT5 regulated genes would advance the ability to combat diseases due to aberrant STAT5 signaling. In the present work a library of human STAT5 bound genomic elements was created and validated. RESULTS: Of several STAT5 responsive genomic regulatory elements identified, one was located within the first intron of the human BCL10 gene. Chromatin immuno-precipitation reactions confirmed constitutive in vivo STAT5 binding to this intronic fragment in various human lymphoid tumor cell lines. Interestingly, non-phosphorylated …

Immune Evasion By Rabies Viruses Through The Maintenance Of Blood-Brain Barrier Integrity., Anirban Roy, Douglas C. Hooper

Department of Cancer Biology Faculty Papers

The attenuated rabies virus (RV) strain Challenge Virus Standard (CVS)-F3 and a highly pathogenic strain associated with the silver-haired bats (SHBRV) can both be cleared from the central nervous system (CNS) tissues by appropriate antiviral immune mechanisms if the effectors are provided access across the blood-brain barrier (BBB). In the case of SHBRV infection, antiviral immunity develops normally in the periphery but fails to open the BBB, generally resulting in a lethal outcome. To determine whether or not an absence in the CNS targeted immune response is associated with the infection with other pathogenic RV strains, we have assessed the …

Inhibition Of Oncogene-Induced Inflammatory Chemokines Using A Farnesyltransferase Inhibitor., Katharine C Degeorge, Brent R Degeorge, James S Testa, Jay L Rothstein

Department of Microbiology and Immunology Faculty Papers

ABSTRACT: BACKGROUND: Farnesyltransferase inhibitors (FTI) are small molecule agents originally formulated to inhibit the oncogenic functions of Ras. Although subsequent analysis of FTI activity revealed wider effects on other pathways, the drug has been demonstrated to reduce Ras signaling by direct measurements. The purpose of the current study was to determine if FTI could be used to inhibit the inflammatory activities of a known Ras-activating human oncoprotein, RET/PTC3. RET/PTC3 is a fusion oncoprotein expressed in the thyroid epithelium of patients afflicted with thyroid autoimmune disease and/or differentiated thyroid carcinoma. Previous studies have demonstrated that RET/PTC3 signals through Ras and can …

Concave Pit-Containing Scaffold Surfaces Improve Stem Cell-Derived Osteoblast Performance And Lead To Significant Bone Tissue Formation., Antonio Graziano, Riccardo D'Aquino, Maria Gabriella Cusella-De Angelis, Gregorio Laino, Adriano Piattelli, Maurizio Pacifici, Alfredo De Rosa, Gianpaolo Papaccio

Department of Orthopaedic Surgery Faculty Papers

BACKGROUND: Scaffold surface features are thought to be important regulators of stem cell performance and endurance in tissue engineering applications, but details about these fundamental aspects of stem cell biology remain largely unclear.

METHODOLOGY AND FINDINGS: In the present study, smooth clinical-grade lactide-coglyolic acid 85:15 (PLGA) scaffolds were carved as membranes and treated with NMP (N-metil-pyrrolidone) to create controlled subtractive pits or microcavities. Scanning electron and confocal microscopy revealed that the NMP-treated membranes contained: (i) large microcavities of 80-120 microm in diameter and 40-100 microm in depth, which we termed primary; and (ii) smaller microcavities of 10-20 microm in diameter …

Smc3 Knockdown Triggers Genomic Instability And P53-Dependent Apoptosis In Human And Zebrafish Cells., Giancarlo Ghiselli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: The structural maintenance of chromosome 3 (SMC3) protein is a constituent of a number of nuclear multimeric protein complexes that are involved in DNA recombination and repair in addition to chromosomal segregation. Overexpression of SMC3 activates a tumorigenic cascade through which mammalian cells acquire a transformed phenotype. This has led us to examine in depth how SMC3 level affects cell growth and genomic stability. In this paper the effect of SMC3 knockdown has been investigated. RESULTS: Mammalian cells that are SMC3 deficient fail to expand in a clonal population. In order to shed light on the underlying mechanism, experiments …

Hinderin, A Five-Domains Protein Including Coiled-Coil Motifs That Binds To Smc3., Chirag A Patel, Giancarlo Ghiselli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: The structural maintenance of chromosome proteins SMC1 and SMC3 play an important role in the maintenance of chromosomal integrity by preventing the premature separation of the sister chromatids at the onset of anaphase. The two proteins are constitutive components of the multimeric complex cohesin and form dimers by interacting at their central globular regions. RESULTS: In order to identify proteins that by binding to SMC3 may interfere with the protein dimerization process, a human cDNA library was screened by the yeast two-hybrid system by using the hinge region of SMC3 as bait. This has lead to the identification of …

The Use Of Time-Resolved Fluorescence Imaging In The Study Of Protein Kinase C Localisation In Cells., Christopher D Stubbs, Stanley W Botchway, Simon J Slater, Anthony W Parker

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Two-photon-excitation fluorescence lifetime imaging (2P-FLIM) was used to investigate the association of protein kinase C alpha (PKCalpha) with caveolin in CHO cells. PKCalpha is found widely in the cytoplasm and nucleus in most cells. Upon activation, as a result of increased intracellular Ca2+ and production of DAG, through G-protein coupled-phospholipase C signalling, PKC translocates to a variety of regions in the cell where it phosphorylates and interacts with many signalling pathways. Due to its wide distribution, discerning a particular interaction from others within the cell is extremely difficult. RESULTS: Fluorescence energy transfer (FRET), between GFP-PKCalpha and DsRed-caveolin, was used …

Characterization Of Subcellular Localization And Stability Of A Splice Variant Of G Alpha I2., Philip B Wedegaertner

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: Alternative mRNA splicing of alpha(i2), a heterotrimeric G protein alpha subunit, has been shown to produce an additional protein, termed salpha(i2). In the salpha(i2) splice variant, 35 novel amino acids replace the normal C-terminal 24 amino acids of alpha(i2). Whereas alpha(i2) is found predominantly at cellular plasma membranes, salpha(i2) has been localized to intracellular Golgi membranes, and the unique 35 amino acids of salpha(i2) have been suggested to constitute a specific targeting signal. RESULTS: This paper proposes and examines an alternative hypothesis: disruption of the normal C-terminus of alpha(i2) produces an unstable protein that fails to localize to plasma …