Medicine and Health Sciences Commons^™

Gene Expression Analysis Of A Murine Model With Pulmonary Vascular Remodeling Compared To End-Stage Ipah Lungs, Kayoko Shimodaira, Yoichiro Okubo, Eri Ochiai, Haruo Nakayama, Harutaka Katano, Megumi Wakayama, Minoru Shinozaki, Takao Ishiwatari, Daisuke Sasai, Naobumi Tochigi, Tetsuo Nemoto, Tsutomu Saji, Katsuhiko Kamei, Kazutoshi Shibuya

Microbiology, Immunology, and Molecular Genetics Faculty Publications

BACKGROUND: Idiopathic pulmonary arterial hypertension (IPAH) continues to be one of the most serious intractable diseases that might start with activation of several triggers representing the genetic susceptibility of a patient. To elucidate what essentially contributes to the onset and progression of IPAH, we investigated factors playing an important role in IPAH by searching discrepant or controversial expression patterns between our murine model and those previously published for human IPAH. We employed the mouse model, which induced muscularization of pulmonary artery leading to hypertension by repeated intratracheal injection of Stachybotrys chartarum, a member of nonpathogenic and ubiquitous fungus in our …

Latexin Is Down-Regulated In Hematopoietic Malignancies And Restoration Of Expression Inhibits Lymphoma Growth, Yi Liu, Dianna Howard, Kyle Rector, Carol Swiderski, Jason Brandon, Lawrence Schook, Jayesh Mehta, J. Scott Bryson, Subbarao Bondada, Ying Liang

Internal Medicine Faculty Publications

Latexin is a negative regulator of hematopoietic stem cell number in mice. Its dysregulated expression in other tumors led us to hypothesize that latexin may have tumor suppressor properties in hematological malignancies. We found that latexin was down-regulated in a variety of leukemia and lymphoma cell lines as well as in CD34+ cells from the blood and marrow of patients with these malignancies. 5-aza-2'-deoxycytodine treatment and bisulfite sequencing revealed hypermethylation of latexin promoter in tumor cells. Retrovirus-mediated latexin overexpression in A20 mouse lymphoma cells inhibited their in vitro growth by 16 fold and in vivo tumor volume by 2 fold. …

Expression Of Muc17 Is Regulated By Hif1Α-Mediated Hypoxic Responses And Requires A Methylation-Free Hypoxia Responsible Element In Pancreatic Cancer., Sho Kitamoto, Seiya Yokoyama, Michiyo Higashi, Norishige Yamada, Shyuichiro Matsubara, Sonshin Takao, Surinder K. Batra, Suguru Yonezawa

Journal Articles: Biochemistry & Molecular Biology

MUC17 is a type 1 membrane-bound glycoprotein that is mainly expressed in the digestive tract. Recent studies have demonstrated that the aberrant overexpression of MUC17 is correlated with the malignant potential of pancreatic ductal adenocarcinomas (PDACs); however, the exact regulatory mechanism of MUC17 expression has yet to be identified. Here, we provide the first report of the MUC17 regulatory mechanism under hypoxia, an essential feature of the tumor microenvironment and a driving force of cancer progression. Our data revealed that MUC17 was significantly induced by hypoxic stimulation through a hypoxia-inducible factor 1α (HIF1α)-dependent pathway in some pancreatic cancer cells (e.g., …

Global Cellular Regulation Including Cardiac Function By Post-Translational Protein Arginylation., Hideko Kaji, Akira Kaji

Department of Biochemistry and Molecular Biology Faculty Papers

In this issue a very significant contribution to cardiology describing critical roles of ATE1 appears by Kurosaka et al. [1]. In view of this paper, as the discoverers of ATE1, we have been asked to contribute an article (editorial) regarding ATE1 (enzyme which transfers arginine from arginyl tRNA to protein acceptors). This short article consists of three sections: 1) a historical anecdote describing how ATE1 was discovered; 2) its possible role in aging and cellular transformation, and most importantly; 3) its role in the development and maintenance of cardiac activity. The last section has direct bearing to the Kurosaka …

Exosome-Mediated Shuttling Of Microrna-29 Regulates Hiv Tat And Morphine-Mediated Neuronal Dysfunction., Guoku Hu, H Yao, A D. Chaudhuri, Sowmya V. Yelamanchili, H Wen, P D. Cheney, Howard S. Fox, Shilpa J. Buch

Journal Articles: Pharmacology & Experimental Neuroscience

Neuronal damage is a hallmark feature of HIV-associated neurological disorders (HANDs). Opiate drug abuse accelerates the incidence and progression of HAND; however, the mechanisms underlying the potentiation of neuropathogenesis by these drugs remain elusive. Opiates such as morphine have been shown to enhance HIV transactivation protein Tat-mediated toxicity in both human neurons and neuroblastoma cells. In the present study, we demonstrate reduced expression of the tropic factor platelet-derived growth factor (PDGF)-B with a concomitant increase in miR-29b in the basal ganglia region of the brains of morphine-dependent simian immunodeficiency virus (SIV)-infected macaques compared with the SIV-infected controls. In vitro relevance …

Mammalian Alteration/Deficiency In Activation 3 (Ada3) Is Essential For Embryonic Development And Cell Cycle Progression., Shakur Mohibi, Channabasavaiah B. Gurumurthy, Alo Nag, Jun Wang, Sameer Mirza, Yousaf Mian, Meghan Quinn, Bryan J. Katafiasz, James D. Eudy, Sanjit Pandey, Chittibabu Guda, Mayumi Naramura, Hamid Band, Vimla Band

Journal Articles: Genetics, Cell Biology & Anatomy

Ada3 protein is an essential component of histone acetyl transferase containing coactivator complexes conserved from yeast to human. We show here that germline deletion of Ada3 in mouse is embryonic lethal, and adenovirus-Cre mediated conditional deletion of Ada3 in Ada3(FL/FL) mouse embryonic fibroblasts leads to a severe proliferation defect which was rescued by ectopic expression of human Ada3. A delay in G(1) to S phase of cell cycle was also seen that was due to accumulation of Cdk inhibitor p27 which was an indirect effect of c-myc gene transcription control by Ada3. We further showed that this defect could be …

Visualizing Spatiotemporal Dynamics Of Apoptosis After G1 Arrest By Human T Cell Leukemia Virus Type 1 Tax And Insights Into Gene Expression Changes Using Microarray-Based Gene Expression Analysis., Mariluz Araínga, Hironobu Murakami, Yoko Aida

Journal Articles: Pharmacology & Experimental Neuroscience

BACKGROUND: Human T cell leukemia virus type 1 (HTLV-1) Tax is a potent activator of viral and cellular gene expression that interacts with a number of cellular proteins. Many reports show that Tax is capable of regulating cell cycle progression and apoptosis both positively and negatively. However, it still remains to understand why the Tax oncoprotein induces cell cycle arrest and apoptosis, or whether Tax-induced apoptosis is dependent upon its ability to induce G1 arrest. The present study used time-lapse imaging to explore the spatiotemporal patterns of cell cycle dynamics in Tax-expressing HeLa cells containing the fluorescent ubiquitination-based cell cycle …

Inhibition Of Soluble Tumor Necrosis Factor Ameliorates Synaptic Alterations And Ca2+ Dysregulation In Aged Rats, Diana M. Sama, Hafiz Mohmmad Abdul, Jennifer L. Furman, Irina A. Artiushin, David E. Szymkowski, Stephen W. Scheff, Christopher M. Norris

Graduate Center for Gerontology Faculty Publications

The role of tumor necrosis factor α (TNF) in neural function has been investigated extensively in several neurodegenerative conditions, but rarely in brain aging, where cognitive and physiologic changes are milder and more variable. Here, we show that protein levels for TNF receptor 1 (TNFR1) are significantly elevated in the hippocampus relative to TNF receptor 2 (TNFR2) in aged (22 months) but not young adult (6 months) Fischer 344 rats. To determine if altered TNF/TNFR1 interactions contribute to key brain aging biomarkers, aged rats received chronic (4-6 week) intracranial infusions of XPro1595: a soluble dominant negative TNF that preferentially inhibits …

Transcriptional Regulatory Network Analysis During Epithelial-Mesenchymal Transformation Of Retinal Pigment Epithelium., Craig H Pratt, Rajanikanth Vadigepalli, Praveen Chakravarthula, Gregory E Gonye, Nancy J Philp, Gerald B Grunwald

Rajanikanth Vadigepalli

PURPOSE: Phenotypic transformation of retinal pigment epithelial (RPE) cells contributes to the onset and progression of ocular proliferative disorders such as proliferative vitreoretinopathy (PVR). The formation of epiretinal membranes in PVR may involve an epithelial-mesenchymal transformation (EMT) of RPE cells as part of an aberrant wound healing response. While the underlying mechanism remains unclear, this likely involves changes in RPE cell gene expression under the control of specific transcription factors (TFs). Thus, the purpose of the present study was to identify TFs that may play a role in this process. METHODS: Regulatory regions of genes that are differentially regulated during …

Nicotine, Ifn-Γ And Retinoic Acid Mediated Induction Of Muc4 In Pancreatic Cancer Requires E2f1 And Stat-1 Transcription Factors And Utilize Different Signaling Cascades., Sateesh Kunigal, Moorthy P. Ponnusamy, Navneet Momi, Surinder K. Batra, Srikumar P. Chellappan

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: The membrane-bound mucins are thought to play an important biological role in cell-cell and cell-matrix interactions, in cell signaling and in modulating biological properties of cancer cell. MUC4, a transmembrane mucin is overexpressed in pancreatic tumors, while remaining undetectable in the normal pancreas, thus indicating a potential role in pancreatic cancer pathogenesis. The molecular mechanisms involved in the regulation of MUC4 gene are not yet fully understood. Smoking is strongly correlated with pancreatic cancer and in the present study; we elucidate the molecular mechanisms by which nicotine as well as agents like retinoic acid (RA) and interferon-γ (IFN-γ) induce …

Pathobiological Implications Of The Expression Of Egfr, Pakt, Nf-Κb And Mic-1 In Prostate Cancer Stem Cells And Their Progenies., Murielle Mimeault, Sonny L. Johansson, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

The progression of prostate cancers (PCs) to locally invasive, androgen-independent and metastatic disease states is generally associated with treatment resistance and disease relapse. The present study was undertaken to establish the possibility of using a combination of specific oncogenic products, including epidermal growth factor receptor (EGFR), pAkt, nuclear factor-kappaB (NF-κB) and macrophage inhibitory cytokine-1 (MIC-1) as biomarkers and therapeutic targets for optimizing the management of patients with localized PC at earlier disease stages. The immunohistochemical and immunofluorescence data have revealed that the expression levels of EGFR, Ser(473)-pAkt, NF-κB p65 and MIC-1 proteins were significantly enhanced in the same subset of …

Gucy2c Opposes Systemic Genotoxic Tumorigenesis By Regulating Akt-Dependent Intestinal Barrier Integrity, Jieru Egeria Lin, Adam Eugene Snook, Peng Li, Brian Arthur Stoecker, Gilbert Won Kim, Michael Sullivan Magee, Alex Vladimir Mejia Garcia, Michael Anthony Valentino, Terry Hyslop, Stephanie Schulz, Scott Arthur Waldman

Department of Pharmacology and Experimental Therapeutics Faculty Papers

The barrier separating mucosal and systemic compartments comprises epithelial cells, annealed by tight junctions, limiting permeability. GUCY2C recently emerged as an intestinal tumor suppressor coordinating AKT1-dependent crypt-villus homeostasis. Here, the contribution of GUCY2C to barrier integrity opposing colitis and systemic tumorigenesis is defined. Mice deficient in GUCY2C (Gucy2c^−/−) exhibited barrier hyperpermeability associated with reduced junctional proteins. Conversely, activation of GUCY2C in mice reduced barrier permeability associated with increased junctional proteins. Further, silencing GUCY2C exacerbated, while activation reduced, chemical barrier disruption and colitis. Moreover, eliminating GUCY2C amplified, while activation reduced, systemic oxidative DNA damage. This genotoxicity was associated …

Regulation Of A Duplicated Locus: Drosophila Sloppy Paired Is Replete With Functionally Overlapping Enhancers., Miki Fujioka, James B Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

In order to investigate regulation and redundancy within the sloppy paired (slp) locus, we analyzed 30 kilobases of DNA encompassing the tandem, coordinately regulated slp1 and slp2 transcription units. We found a remarkable array of stripe enhancers with overlapping activities surrounding the slp1 transcription unit, and, unexpectedly, glial cell enhancers surrounding slp2. The slp stripe regulatory region generates 7 stripes at blastoderm, and later 14 stripes that persist throughout embryogenesis. Phylogenetic analysis among drosophilids suggests that the multiplicity of stripe enhancers did not evolve through recent duplication. Most of the direct integration among cis-regulatory modules appears to be simply additive, …

Mir-25 Targets Tnf-Related Apoptosis Inducing Ligand (Trail) Death Receptor-4 And Promotes Apoptosis Resistance In Cholangiocarcinoma., Nataliya Razumilava, Steve F. Bronk, Rory L. Smoot, Christian D. Fingas, Nathan W. Werneburg, Lewis R. Roberts, Justin L. Mott

Journal Articles: Biochemistry & Molecular Biology

It has been established that microRNA expression and function contribute to phenotypic features of malignant cells, including resistance to apoptosis. Although targets and functional roles for a number of microRNAs have been described in cholangiocarcinoma, many additional microRNAs dysregulated in this tumor have not been assigned functional roles. In this study, we identify elevated miR-25 expression in malignant cholangiocarcinoma cell lines as well as patient samples. In cultured cells, treatment with the Smoothened inhibitor, cyclopamine, reduced miR-25 expression, suggesting Hedgehog signaling stimulates miR-25 production. Functionally, miR-25 was shown to protect cells against TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. Correspondingly, antagonism of …

Interferon-Α Regulates Glutaminase 1 Promoter Through Stat1 Phosphorylation: Relevance To Hiv-1 Associated Neurocognitive Disorders., Lixia Zhao, Yunlong Huang, Changhai Tian, Lynn Taylor, Norman Curthoys, Yi Wang, Hamilton Vernon, Jialin C. Zheng

Journal Articles: Pharmacology & Experimental Neuroscience

HIV-1 associated neurocognitive disorders (HAND) develop during progressive HIV-1 infection and affect up to 50% of infected individuals. Activated microglia and macrophages are critical cell populations that are involved in the pathogenesis of HAND, which is specifically related to the production and release of various soluble neurotoxic factors including glutamate. In the central nervous system (CNS), glutamate is typically derived from glutamine by mitochondrial enzyme glutaminase. Our previous study has shown that glutaminase is upregulated in HIV-1 infected monocyte-derived-macrophages (MDM) and microglia. However, how HIV-1 leads to glutaminase upregulation, or how glutaminase expression is regulated in general, remains unclear. In …

Decorin Protein Core Affects The Global Gene Expression Profile Of The Tumor Microenvironment In A Triple-Negative Orthotopic Breast Carcinoma Xenograft Model., Simone Buraschi, Thomas Neill, Rick T Owens, Leonardo A Iniguez, George Purkins, Rajanikanth Vadigepalli, Barry Evans, Liliana Schaefer, Stephen C Peiper, Zi-Xuan Wang, Renato V Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Decorin, a member of the small leucine-rich proteoglycan gene family, exists and functions wholly within the tumor microenvironment to suppress tumorigenesis by directly targeting and antagonizing multiple receptor tyrosine kinases, such as the EGFR and Met. This leads to potent and sustained signal attenuation, growth arrest, and angiostasis. We thus sought to evaluate the tumoricidal benefits of systemic decorin on a triple-negative orthotopic breast carcinoma xenograft model. To this end, we employed a novel high-density mixed expression array capable of differentiating and simultaneously measuring gene signatures of both Mus musculus (stromal) and Homo sapiens (epithelial) tissue origins. We found that …

Myd88-Dependent Signaling Influences Fibrosis And Alternative Macrophage Activation During Staphylococcus Aureus Biofilm Infection., Mark L. Hanke, Amanda Angle, Tammy Kielian

Journal Articles: Pathology and Microbiology

Bacterial biofilms represent a significant therapeutic challenge based on their ability to evade host immune and antibiotic-mediated clearance. Recent studies have implicated IL-1β in biofilm containment, whereas Toll-like receptors (TLRs) had no effect. This is intriguing, since both the IL-1 receptor (IL-1R) and most TLRs impinge on MyD88-dependent signaling pathways, yet the role of this key adaptor in modulating the host response to biofilm growth is unknown. Therefore, we examined the course of S. aureus catheter-associated biofilm infection in MyD88 knockout (KO) mice. MyD88 KO animals displayed significantly increased bacterial burdens on catheters and surrounding tissues during early infection, which …

Blood-Brain Barrier Abnormalities Caused By Hiv-1 Gp120: Mechanistic And Therapeutic Implications., Jean-Pierre Louboutin, David S Strayer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The blood-brain barrier (BBB) is compromised in many systemic and CNS diseases, including HIV-1 infection of the brain. We studied BBB disruption caused by HIV-1 envelope glycoprotein 120 (gp120) as a model. Exposure to gp120, whether acute [by direct intra-caudate-putamen (CP) injection] or chronic [using SV(gp120), an experimental model of ongoing production of gp120] disrupted the BBB, and led to leakage of vascular contents. Gp120 was directly toxic to brain endothelial cells. Abnormalities of the BBB reflect the activity of matrix metalloproteinases (MMPs). These target laminin and attack the tight junctions between endothelial cells and BBB basal laminae. MMP-2 and …

Emergence Of Bimodal Cell Population Responses From The Interplay Between Analog Single-Cell Signaling And Protein Expression Noise., Marc R Birtwistle, Jens Rauch, Anatoly Kiyatkin, Edita Aksamitiene, Maciej Dobrzyński, Jan B. Hoek, Walter Kolch, Babatunde A Ogunnaike, Boris N Kholodenko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Cell-to-cell variability in protein expression can be large, and its propagation through signaling networks affects biological outcomes. Here, we apply deterministic and probabilistic models and biochemical measurements to study how network topologies and cell-to-cell protein abundance variations interact to shape signaling responses.

RESULTS: We observe bimodal distributions of extracellular signal-regulated kinase (ERK) responses to epidermal growth factor (EGF) stimulation, which are generally thought to indicate bistable or ultrasensitive signaling behavior in single cells. Surprisingly, we find that a simple MAPK/ERK-cascade model with negative feedback that displays graded, analog ERK responses at a single cell level can explain the experimentally …