Medical Cell Biology Commons^™

Role And Mechanism Of Arsenic In Regulating Angiogenesis., Ling-Zhi Liu, Yue Jiang, Richard L Carpenter, Yi Jing, Stephen C Peiper, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Arsenic is a wide spread carcinogen associated with several kinds of cancers including skin, lung, bladder, and liver cancers. Lung is one of the major targets of arsenic exposure. Angiogenesis is the pivotal process during carcinogenesis and chronic pulmonary diseases, but the role and mechanism of arsenic in regulating angiogenesis remain to be elucidated. In this study we show that short time exposure of arsenic induces angiogenesis in both human immortalized lung epithelial cells BEAS-2B and adenocarcinoma cells A549. To study the molecular mechanism of arsenic-inducing angiogenesis, we find that arsenic induces reactive oxygen species (ROS) generation, which activates AKT …

Mitochondrial Oxidative Stress Drives Tumor Progression And Metastasis: Should We Use Antioxidants As A Key Component Of Cancer Treatment And Prevention?, Federica Sotgia, Ubaldo E Martinez-Outschoorn, Michael P Lisanti

Department of Stem Cell Biology and Regenerative Medicine Faculty Papers & Presentations

The functional role of oxidative stress in cancer pathogenesis has long been a hotly debated topic. A study published this month in BMC Cancer by Goh et al., directly addresses this issue by using a molecular genetic approach, via an established mouse animal model of human breast cancer. More specifically, alleviation of mitochondrial oxidative stress, via transgenic over-expression of catalase (an anti-oxidant enzyme) targeted to mitochondria, was sufficient to lower tumor grade (from high-to-low) and to dramatically reduce metastatic tumor burden by >12-fold. Here, we discuss these new findings and place them in the context of several other recent studies …

The Interplay Between Nf-Kappab And E2f1 Coordinately Regulates Inflammation And Metabolism In Human Cardiac Cells., Xavier Palomer, David Álvarez-Guardia, Mercy M Davidson, Tung O Chan, Arthur M Feldman, Manuel Vázquez-Carrera

Department of Medicine Faculty Papers

Pyruvate dehydrogenase kinase 4 (PDK4) inhibition by nuclear factor-κB (NF-κB) is related to a shift towards increased glycolysis during cardiac pathological processes such as cardiac hypertrophy and heart failure. The transcription factors estrogen-related receptor-α (ERRα) and peroxisome proliferator-activated receptor (PPAR) regulate PDK4 expression through the potent transcriptional coactivator PPARγ coactivator-1α (PGC-1α). NF-κB activation in AC16 cardiac cells inhibit ERRα and PPARβ/δ transcriptional activity, resulting in reduced PGC-1α and PDK4 expression, and an enhanced glucose oxidation rate. However, addition of the NF-κB inhibitor parthenolide to these cells prevents the downregulation of PDK4 expression but not ERRα and PPARβ/δ DNA binding activity, …

Microarray-Based Analysis Of Differential Gene Expression Between Infective And Noninfective Larvae Of Strongyloides Stercoralis., Roshan Ramanathan, Sudhir Varma, José M C Ribeiro, Timothy G Myers, Thomas J Nolan, David Abraham, James B Lok, Thomas B Nutman

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: Differences between noninfective first-stage (L1) and infective third-stage (L3i) larvae of parasitic nematode Strongyloides stercoralis at the molecular level are relatively uncharacterized. DNA microarrays were developed and utilized for this purpose.

METHODS AND FINDINGS: Oligonucleotide hybridization probes for the array were designed to bind 3,571 putative mRNA transcripts predicted by analysis of 11,335 expressed sequence tags (ESTs) obtained as part of the Nematode EST project. RNA obtained from S. stercoralis L3i and L1 was co-hybridized to each array after labeling the individual samples with different fluorescent tags. Bioinformatic predictions of gene function were developed using a novel cDNA Annotation …

Comparison Of Human Memory Cd8 T Cell Responses To Adenoviral Early And Late Proteins In Peripheral Blood And Lymphoid Tissue., Amita Joshi, Biwei Zhao, Cara Romanowski, David Rosen, Phyllis Flomenberg

Department of Microbiology and Immunology Faculty Papers

Treatment of invasive adenovirus (Ad) disease in hematopoietic stem cell transplant (SCT) recipients with capsid protein hexon-specific donor T cells is under investigation. We propose that cytotoxic T cells (CTLs) targeted to the late protein hexon may be inefficient in vivo because the early Ad protein E3-19K downregulates HLA class I antigens in infected cells. In this study, CD8+ T cells targeted to highly conserved HLA A2-restricted epitopes from the early regulatory protein DNA polymerase (P-977) and late protein hexon (H-892) were compared in peripheral blood (PB) and tonsils of naturally infected adults. In tonsils, epitope-specific pentamers detected a significantly …

Mitostatin Is Down-Regulated In Human Prostate Cancer And Suppresses The Invasive Phenotype Of Prostate Cancer Cells., Matteo Fassan, Domenico D'Arca, Juraj Letko, Andrea Vecchione, Marina P Gardiman, Peter Mccue, Bernadette Wildemore, Massimo Rugge, Dolores Shupp-Byrne, Leonard G Gomella, Andrea Morrione, Renato V Iozzo, Raffaele Baffa

Kimmel Cancer Center Faculty Papers

MITOSTATIN, a novel putative tumor suppressor gene induced by decorin overexpression, is expressed in most normal human tissues but is markedly down-regulated in advanced stages of mammary and bladder carcinomas. Mitostatin negatively affects cell growth, induces cell death and regulates the expression and activation levels of Hsp27. In this study, we demonstrated that ectopic expression of Mitostatin in PC3, DU145, and LNCaP prostate cancer cells not only induced a significant reduction in cell growth, but also inhibited migration and invasion. Moreover, Mitostatin inhibited colony formation in soft-agar of PC3 and LNCaP cells as well as tumorigenicity of LNCaP cells in …

The Variable Presentations Of Anaplastic Spindle Cell Squamous Carcinoma Associated With Tall Cell Variant Of Papillary Thyroid Carcinoma., Pallavi P Gopal, Kathleen T Montone, Zubair Baloch, Madalina Tuluc, Virginia Livolsi

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: In 1976, Hawk and Hazard described the tall cell variant (TCV) of papillary thyroid carcinoma (PTC). While the lesions they described had cytologic features of papillary carcinoma, they showed more aggressive behavior with a greater propensity for extrathyroid extension and lymphovascular invasion than classic PTC. In 1991, Bronner and LiVolsi described a series of patients with TCV that progressed to spindle cell squamous carcinoma (SCSC), a unique form of anaplastic thyroid carcinoma. This study describes the variable clinical and pathologic presentations in 31 patients with anaplastic SCSC arising in association with TCV.

METHODS: The surgical pathology archives as well …

A Compact Guide To The Diagnosis And Management Of Neurofibromatosis Type 1, Timothy Beer, David Strayer, Md, Phd

Department of Pathology, Anatomy, and Cell Biology Resident's Posters

Brief Introduction

Neurofibromatosis type 1 (NF-1) is a multisystem neurocutaneous disorder resulting from mutations in the NF-1 gene on chromosome 17 (q11.2). Mutations in NF-1 result in deficient activity of the tumor suppresor protein neurofibromin, allowing for uncontrolled constitutive activity of the proliferative Raspathway in several neural cell types, including neurons, oligodendrocytes, astrocytes and Schawnn cells. Half of NF-1 cases are inherited in autosomal dominant fashion, while half develop sporadically. The syndrome has 100% penetrance but highly variable expressivity. The prevalence of this syndrome is 1/3,000, making it common enough to warrant YOU, the physician, taking a moment to learn …

Mir-21 Induced Angiogenesis Through Akt And Erk Activation And Hif-1Α Expression., Ling-Zhi Liu, Chongyong Li, Qi Chen, Yi Jing, Richard Carpenter, Yue Jiang, Hsiang-Fu Kung, Lihui Lai, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

MicroRNAs (miRNAs) are endogenous, small noncoding RNAs that play important roles in various cellular functions and tumor development. Recent studies have indicated that miR-21 is one of the important miRNAs associated with tumor growth and metastasis, but the role and molecular mechanism of miR-21 in regulating tumor angiogenesis remain to be elucidated. In this study, miR-21 was overexpressed by transfecting pre-miR-21 into human prostate cancer cells and tumor angiogenesis was assayed using chicken chorioallantoic membrane (CAM). We found that overexpression of miR-21 in DU145 cells increased the expression of HIF-1α and VEGF, and induced tumor angiogenesis. AKT and extracellular regulated …

Aging Enhances Serum Cytokine Response But Not Task-Induced Grip Strength Declines In A Rat Model Of Work-Related Musculoskeletal Disorders., Dong L Xin, Michelle Y Harris, Christine K Wade, Mamta Amin, Ann E Barr, Mary F Barbe

Department of Physical Therapy Faculty Papers

BACKGROUND: We previously reported early tissue injury, increased serum and tissue inflammatory cytokines and decreased grip in young rats performing a moderate demand repetitive task. The tissue cytokine response was transient, the serum response and decreased grip were still evident by 8 weeks. Thus, here, we examined their levels at 12 weeks in young rats. Since aging is known to enhance serum cytokine levels, we also examined aged rats.

METHODS: Aged and young rats, 14 mo and 2.5 mo of age at onset, respectfully, were trained 15 min/day for 4 weeks, and then performed a high repetition, low force (HRLF) …

Fus Transgenic Rats Develop The Phenotypes Of Amyotrophic Lateral Sclerosis And Frontotemporal Lobar Degeneration., Cao Huang, Hongxia Zhou, Jianbin Tong, Han Chen, Yong-Jian Liu, Dian Wang, Xiaotao Wei, Xu-Gang Xia

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Fused in Sarcoma (FUS) proteinopathy is a feature of frontotemporal lobar dementia (FTLD), and mutation of the fus gene segregates with FTLD and amyotrophic lateral sclerosis (ALS). To study the consequences of mutation in the fus gene, we created transgenic rats expressing the human fus gene with or without mutation. Overexpression of a mutant (R521C substitution), but not normal, human FUS induced progressive paralysis resembling ALS. Mutant FUS transgenic rats developed progressive paralysis secondary to degeneration of motor axons and displayed a substantial loss of neurons in the cortex and hippocampus. This neuronal loss was accompanied by ubiquitin aggregation and …

Prolactin-Induced Mouse Mammary Carcinomas Model Estrogen Resistant Luminal Breast Cancer., Lisa M Arendt, Debra E Rugowski, Tara A Grafwallner-Huseth, Maria Jose Garcia-Barchino, Hallgeir Rui, Linda A Schuler

Kimmel Cancer Center Faculty Papers

INTRODUCTION: Tumors that express estrogen receptor alpha (ERα+) comprise 75% of breast cancers in women. While treatments directed against this receptor have successfully lowered mortality rates, many primary tumors initially or later exhibit resistance. The paucity of murine models of this "luminal" tumor subtype has hindered studies of factors that promote their pathogenesis and modulate responsiveness to estrogen-directed therapeutics. Since epidemiologic studies closely link prolactin and the development of ERα+ tumors in women, we examined characteristics of the aggressive ERα+ and ERα- carcinomas which develop in response to mammary prolactin in a murine transgenic model (neu-related lipocalin- prolactin (NRL-PRL)). To …

Evidence-Based Genomic Diagnosis Characterized Chromosomal And Cryptic Imbalances In 30 Elderly Patients With Myelodysplastic Syndrome And Acute Myeloid Leukemia., Renu Bajaj, Fang Xu, Bixia Xiang, Katherine Wilcox, Autumn J Diadamo, Rachana Kumar, Alexandra Pietraszkiewicz, Stephanie Halene, Peining Li

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: To evaluate the clinical validity of genome-wide oligonucleotide array comparative genomic hybridization (aCGH) for detecting somatic abnormalities, we have applied this genomic analysis to 30 cases (13 MDS and 17 AML) with clonal chromosomal abnormalities detected in more than 50% of analyzed metaphase cells.

RESULTS: The aCGH detected all numerical chromosomal gains and losses from the mainline clones and 113 copy number alterations (CNAs) ranging from 0.257 to 102.519 megabases (Mb). Clinically significant recurrent deletions of 5q (involving the RPS14 gene), 12p12.3 (ETV6 gene), 17p13 (TP53 gene), 17q11.2 (NF1 gene) and 20q, double minutes containing the MYC gene and …

Phosphorylation Meets Nuclear Import: A Review., Jonathan D Nardozzi, Kaylen Lott, Gino Cingolani

Department of Biochemistry and Molecular Biology Faculty Papers

Phosphorylation is the most common and pleiotropic modification in biology, which plays a vital role in regulating and finely tuning a multitude of biological pathways. Transport across the nuclear envelope is also an essential cellular function and is intimately linked to many degeneration processes that lead to disease. It is therefore not surprising that phosphorylation of cargos trafficking between the cytoplasm and nucleus is emerging as an important step to regulate nuclear availability, which directly affects gene expression, cell growth and proliferation. However, the literature on phosphorylation of nucleocytoplasmic trafficking cargos is often confusing. Phosphorylation, and its mirror process dephosphorylation, …

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 …

Biological Rationale For The Use Of Dna Methyltransferase Inhibitors As New Strategy For Modulation Of Tumor Response To Chemotherapy And Radiation., Giovanni L Gravina, Claudio Festuccia, Francesco Marampon, Vladimir M Popov, Richard G Pestell, Bianca M Zani, Vincenzo Tombolini

Kimmel Cancer Center Faculty Papers

Epigenetic modifications play a key role in the patho-physiology of many tumors and the current use of agents targeting epigenetic changes has become a topic of intense interest in cancer research. DNA methyltransferase (DNMT) inhibitors represent a promising class of epigenetic modulators. Research performed yielded promising anti-tumorigenic activity for these agents in vitro and in vivo against a variety of hematologic and solid tumors. These epigenetic modulators cause cell cycle and growth arrest, differentiation and apoptosis. Rationale for combining these agents with cytotoxic therapy or radiation is straightforward since the use of DNMT inhibitor offers greatly improved access for cytotoxic …

A Role For The Histone Deacetylase Hdac4 In The Life-Cycle Of Hiv-1-Based Vectors., Johanna A Smith, Jennifer Yeung, Gary D Kao, René Daniel

Department of Medicine Faculty Papers

HIV-1 integration is mediated by the HIV-1 integrase protein, which joins 3'-ends of viral DNA to host cell DNA. To complete the integration process, HIV-1 DNA has to be joined to host cell DNA also at the 5'-ends. This process is called post-integration repair (PIR). Integration and PIR involve a number of cellular co-factors. These proteins exhibit different degrees of involvement in integration and/or PIR. Some are required for efficient integration or PIR. On the other hand, some reduce the efficiency of integration. Finally, some are involved in integration site selection. We have studied the role of the histone deacetylase …

Physiologically Based Pharmacokinetics Of Molecular Imaging Nanoparticles For Mrna Detection Determined In Tumor-Bearing Mice., Armin W Opitz, Eric Wickstrom, Mathew L Thakur, Norman J Wagner

Kimmel Cancer Center Faculty Papers

Disease detection and management might benefit from external imaging of disease gene mRNAs. Previously we designed molecular imaging nanoparticles (MINs) based on peptide nucleic acids complementary to cancer gene mRNAs. The MINs included contrast agents and analogs of insulin-like growth factor 1 (IGF-1). Analysis of MIN tumor uptake data showed stronger binding in tumors than in surrounding tissues. We hypothesized that MINs with an IGF-1 analog stay in circulation by binding to IGF-binding proteins. To test that hypothesis, we fit the tissue distribution results of several MINs in xenograft-bearing mice to a physiological pharmacokinetics model. Fitting experimental tissue distribution data …

Assessment Of Epidermal Growth Factor Receptor (Egfr) Expression In Human Meningioma., A Gabriella Wernicke, Adam P Dicker, Michal Whiton, Jana Ivanidze, Terry Hyslop, Elizabeth H Hammond, Arie Perry, David W Andrews, Lawrence Kenyon

Kimmel Cancer Center Faculty Papers

PURPOSE: This study explores whether meningioma expresses epidermal growth factor receptor (EGFR) and determines if there is a correlation between the WHO grade of this tumor and the degree of EGFR expression.

METHODS: Following institutional review board approval, 113 meningioma specimens from 89 patients were chosen. Of these, 85 were used for final analysis. After a blinded review, immunohistochemical stains for EGFR were performed. Staining intensity (SI) was scored on a scale 0-3 (from no staining to strong staining). Staining percentage of immunoreactive cells (SP) was scored 1-5 (from the least to the maximum percent of the specimen staining). Immunohistochemical …

Transgenic Rat Model Of Neurodegeneration Caused By Mutation In The Tdp Gene., Hongxia Zhou, Cao Huang, Han Chen, Dian Wang, Carlisle P Landel, Pedro Yuxing Xia, Robert Bowser, Yong-Jian Liu, Xu Gang Xia

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

TDP-43 proteinopathies have been observed in a wide range of neurodegenerative diseases. Mutations in the gene encoding TDP-43 (i.e., TDP) have been identified in amyotrophic lateral sclerosis (ALS) and in frontotemporal lobe degeneration associated with motor neuron disease. To study the consequences of TDP mutation in an intact system, we created transgenic rats expressing normal human TDP or a mutant form of human TDP with a M337V substitution. Overexpression of mutant, but not normal, TDP caused widespread neurodegeneration that predominantly affected the motor system. TDP mutation reproduced ALS phenotypes in transgenic rats, as seen by progressive degeneration of motor neurons …

Differential Impact Of Tumor Suppressor Pathways On Dna Damage Response And Therapy-Induced Transformation In A Mouse Primary Cell Model., A Kathleen Mcclendon, Jeffry L Dean, Adam Ertel, Erik S Knudsen

Department of Cancer Biology Faculty Papers

The RB and p53 tumor suppressors are mediators of DNA damage response, and compound inactivation of RB and p53 is a common occurrence in human cancers. Surprisingly, their cooperation in DNA damage signaling in relation to tumorigenesis and therapeutic response remains enigmatic. In the context of individuals with heritable retinoblastoma, there is a predilection for secondary tumor development, which has been associated with the use of radiation-therapy to treat the primary tumor. Furthermore, while germline mutations of the p53 gene are critical drivers for cancer predisposition syndromes, it is postulated that extrinsic stresses play a major role in promoting varying …

Imaging Spontaneous Mmtvneu Transgenic Murine Mammary Tumors: Targeting Metabolic Activity Versus Genetic Products., Mathew L Thakur, Devakumar Devadhas, Kaijun Zhang, Richard G Pestell, Chenguang Wang, Peter Mccue, Eric Wickstrom

Department of Radiology Faculty Papers

INTRODUCTION: Despite the great strides made in imaging breast cancer (BC) in humans, the current imaging modalities miss up to 30% of BC, do not distinguish malignant lesions from benign ones, and require histologic examinations for which invasive biopsy must be performed. Annually in the United States, approximately 5.6 million biopsies find benign lesions. More than 50% of human BCs overexpress cyclin D1, and all BCs exhibit VPAC1 oncogene products. Together, these gene products may provide an excellent biomarker for the early and accurate detection of BC. We have evaluated 4 biologically active peptide analogs that have high affinity for …

The Production Of Antibody By Invading B Cells Is Required For The Clearance Of Rabies Virus From The Central Nervous System., D Craig Hooper, Timothy W Phares, Marzena J Fabis, Anirban Roy

Department of Cancer Biology Faculty Papers

BACKGROUND: The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus.

METHODOLOGY/PRINCIPAL FINDINGS: Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell-deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies …

Intracellular Bacteria Encode Inhibitory Snare-Like Proteins., Fabienne Paumet, Jordan Wesolowski, Alejandro Garcia-Diaz, Cedric Delevoye, Nathalie Aulner, Howard A Shuman, Agathe Subtil, James E Rothman

Department of Microbiology and Immunology Faculty Papers

Pathogens use diverse molecular machines to penetrate host cells and manipulate intracellular vesicular trafficking. Viruses employ glycoproteins, functionally and structurally similar to the SNARE proteins, to induce eukaryotic membrane fusion. Intracellular pathogens, on the other hand, need to block fusion of their infectious phagosomes with various endocytic compartments to escape from the degradative pathway. The molecular details concerning the mechanisms underlying this process are lacking. Using both an in vitro liposome fusion assay and a cellular assay, we showed that SNARE-like bacterial proteins block membrane fusion in eukaryotic cells by directly inhibiting SNARE-mediated membrane fusion. More specifically, we showed that …

N-Glycosylation Status Of E-Cadherin Controls Cytoskeletal Dynamics Through The Organization Of Distinct Β-Catenin- And Γ-Catenin-Containing Ajs., Basem T Jamal, Mihai Nita-Lazar, Zhennan Gao, Bakr Amin, Janice Walker, Maria A Kukuruzinska

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

N-glycosylation of E-cadherin has been shown to inhibit cell-cell adhesion. Specifically, our recent studies have provided evidence that the reduction of E-cadherin N-glycosylation promoted the recruitment of stabilizing components, vinculin and serine/threonine protein phosphatase 2A (PP2A), to adherens junctions (AJs) and enhanced the association of AJs with the actin cytoskeleton. Here, we examined the details of how N-glycosylation of E-cadherin affected the molecular organization of AJs and their cytoskeletal interactions. Using the hypoglycosylated E-cadherin variant, V13, we show that V13/β-catenin complexes preferentially interacted with PP2A and with the microtubule motor protein dynein. This correlated with dephosphorylation of the microtubule-associated protein …

Intra-Tumor Heterogeneity Of Mlh1 Promoter Methylation Revealed By Deep Single Molecule Bisulfite Sequencing., Katherine E Varley, David G Mutch, Tina B Edmonston, Paul J Goodfellow, Robi D Mitra

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

A single tumor may contain cells with different somatic mutations. By characterizing this genetic heterogeneity within tumors, advances have been made in the prognosis, treatment and understanding of tumorigenesis. In contrast, the extent of epigenetic intra-tumor heterogeneity and how it influences tumor biology is under-explored. We have characterized epigenetic heterogeneity within individual tumors using next-generation sequencing. We used deep single molecule bisulfite sequencing and sample-specific DNA barcodes to determine the spectrum of MLH1 promoter methylation across an average of 1000 molecules in each of 33 individual samples in parallel, including endometrial cancer, matched blood and normal endometrium. This first glimpse, …

Nerve Injection Of Viral Vectors Efficiently Transfers Transgenes Into Motor Neurons And Delivers Rnai Therapy Against Als., Rui Wu, Hongyan Wang, Xugang Xia, Hongxia Zhou, Chunyan Liu, Maria Castro, Zuoshang Xu

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

RNA interference (RNAi) mediates sequence-specific gene silencing, which can be harnessed to silencing disease-causing genes for therapy. Particularly suitable diseases are those caused by dominant, gain-of-function type of gene mutations. In these diseases, the mutant gene generates a mutant protein or RNA product, which possesses toxic properties that harm cells. By silencing the mutant gene, the toxicity can be lessened because the amount of the toxic product is lowered in cells. In this report, we tested RNAi therapy in a mouse model for amyotrophic lateral sclerosis (ALS), which causes motor neuron degeneration, paralysis, and death. We used a transgenic model …

Interaction With Lc8 Is Required For Pak1 Nuclear Import And Is Indispensable For Zebrafish Development., Christine M Lightcap, Gabor Kari, Luis E Arias-Romero, Jonathan Chernoff, Ulrich Rodeck, John C Williams

Department of Biochemistry and Molecular Biology Faculty Papers

Pak1 (p21 activated kinase 1) is a serine/threonine kinase implicated in regulation of cell motility and survival and in malignant transformation of mammary epithelial cells. In addition, the dynein light chain, LC8, has been described to cooperate with Pak1 in malignant transformation of breast cancer cells. Pak1 itself may aid breast cancer development by phosphorylating nuclear proteins, including estrogen receptor alpha. Recently, we showed that the LC8 binding site on Pak1 is adjacent to the nuclear localization sequence (NLS) required for Pak1 nuclear import. Here, we demonstrate that the LC8-Pak1 interaction is necessary for epidermal growth factor (EGF)-induced nuclear import …

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 …