Medical Toxicology Commons^™

An Optimized Solid-Phase Reduction And Capture Strategy For The Study Of Reversibly-Oxidized Cysteines And Its Application To Metal Toxicity, John Andrew Hitron

Theses and Dissertations--Toxicology and Cancer Biology

The reversible oxidation of cysteine by reactive oxygen species (ROS) is both a mechanism for cellular protein signaling as well as a cause of cellular injury and death through the generation of oxidative stress. The study of cysteine oxidation is complicated by the methodology currently available to isolate and enrich oxidized-cysteine containing proteins. We sought to simplify this process by reducing the time needed to process samples and reducing sample loss and contamination risk.

We accomplished this by eliminating precipitation steps needed for the protocol by (a) introducing an in-solution NEM-quenching step prior to reduction and (b) replacing soluble dithiothreitol …

Targeting Ribosome Assembly Factors Selectively Protects P53 Positive Cells From Chemotherapeutic Agents, Russell T. Sapio, Anastasiya Nezdyur, Matthew Krevetski, Leonid Anikin, Vincent J. Manna, N. Minkovsky, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Many chemotherapeutic agents act in a nondiscriminatory fashion, targeting both cancerous and noncancerous cells in Sphase and Mphase. One approach to reduce the toxic side effects in normal tissue is to exploit the differences in p53 functionality between cancerous and noncancerous cells. For example, activating p53 signaling by nongenotoxic means can transiently arrest noncancerous p53 positive cells in G1 phase and protect them from the cytotoxic effects of chemotherapeutic drugs. However, since most cancerous cells have faulty p53 signaling, they will proceed to cycle, and continue to be affected by the drug. In this study we asked if this G1‐phase …

Tumor Suppressor Pdcd4 Attenuates Sin1 Translation To Inhibit Invasion In Colon Carcinoma, Qing Wang, Jiang Zhu, Ya-Wen Wang, Yong Dai, Yanlei Wang, Chi Wang, Jinpeng Liu, Alyson Baker, Nancy H. Colburn, Hsin-Sheng Yang

Toxicology and Cancer Biology Faculty Publications

Programmed cell death 4 (Pdcd4), a tumor invasion suppressor, is frequently downregulated in colorectal cancer and other cancers. In this study, we find that loss of Pdcd4 increases the activity of mammalian target of rapamycin complex 2 (mTORC2) and thereby upregulates Snail expression. Examining the components of mTORC2 showed that Pdcd4 knockdown increased the protein but not mRNA level of stress-activated-protein kinase interacting protein 1 (Sin1), which resulted from enhanced Sin1 translation. To understand how Pdcd4 regulates Sin1 translation, the SIN1 5′ untranslated region (5′UTR) was fused with luciferase reporter and named as 5′Sin1-Luc. Pdcd4 knockdown/knockout significantly increased the translation …

Parallelization Of A Three-Dimensional Full Multigrid Algorithm To Simulate Tumor Growth, Dylan Goodin, Chin F. Ng, Hermann B. Frieboes

Commonwealth Computational Summit

We present the performance gains of an openMP implementation of a fully adaptive nonlinear full multigrid (FMG) algorithm to simulate three-dimensional multispecies desmoplastic tumor growth on computer systems of varying processing capabilities. The FMG algorithm is applied to solve a recently published thermodynamic mixture model that uses a diffuse interface approach with fourth-order reaction-advection-diffusion PDEs (Cahn-Hilliard-type equations) that are coupled, nonlinear, and numerically stiff. The model includes multiple cell species and extracellular matrix (ECM), with adhesive and elastic energy contributions in chemical potential terms, as well as including blood and lymphatic vessels represented as continuous vasculatures. Advection-reaction-diffusion PDEs are employed …

Glycolytic Reprogramming Through Pck2 Regulates Tumor Initiation Of Prostate Cancer Cells, Jiangsha Zhao, Jieran Li, Teresa W.M. Fan, Steven X. Hou

Toxicology and Cancer Biology Faculty Publications

Tumor-initiating cells (TICs) play important roles in tumor progression and metastasis. Identifying the factors regulating TICs may open new avenues in cancer therapy. Here, we show that TIC-enriched prostate cancer cell clones use more glucose and secrete more lactate than TIC-low clones. We determined that elevated levels of phosphoenolpyruvate carboxykinase isoform 2 (PCK2) are critical for the metabolic switch and the maintenance of TICs in prostate cancer. Information from prostate cancer patient databases revealed that higher PCK2 levels correlated with more aggressive tumors and lower survival rates. PCK2 knockdown resulted in low TIC numbers, increased cytosolic acetyl-CoA and cellular protein …

Analytics For Non-Invasive Skin Imaging And Actinic Damage, Christina E. Borchers

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Mutsβ Abundance And Msh3 Atp Hydrolysis Activity Are Important Drivers Of Ctg•Cag Repeat Expansions, Norma Keogh, Kara Y. Chan, Guo-Min Li, Robert S. Lahue

Toxicology and Cancer Biology Faculty Publications

CTG•CAG repeat expansions cause at least twelve inherited neurological diseases. Expansions require the presence, not the absence, of the mismatch repair protein MutSβ (Msh2-Msh3 heterodimer). To evaluate properties of MutSβ that drive expansions, previous studies have tested under-expression, ATPase function or polymorphic variants of Msh2 and Msh3, but in disparate experimental systems. Additionally, some variants destabilize MutSβ, potentially masking the effects of biochemical alterations of the variations. Here, human Msh3 was mutated to selectively inactivate MutSβ. Msh3^−/− cells are severely defective for CTG•CAG repeat expansions but show full activity on contractions. Msh3^−/− cells provide a single, isogenic system …

Chemotherapy-Induced Tissue Injury: An Insight Into The Role Of Extracellular Vesicles-Mediated Oxidative Stress Responses, Chontida Yarana, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

The short- and long-term side effects of chemotherapy limit the maximum therapeutic dose and impair quality of life of survivors. Injury to normal tissues, especially chemotherapy-induced cardiomyopathy, is an unintended outcome that presents devastating health impacts. Approximately half of the drugs approved by the Food and Drug Administration for cancer treatment are associated with the generation of reactive oxygen species, and Doxorubicin (Dox) is one of them. Dox undergoes redox cycling by involving its quinone structure in the production of superoxide free radicals, which are thought to be instrumental to the role it plays in cardiomyopathy. Dox-induced protein oxidation changes …

Loss Of Fructose-1,6-Bisphosphatase Induces Glycolysis And Promotes Apoptosis Resistance Of Cancer Stem-Like Cells: An Important Role In Hexavalent Chromium-Induced Carcinogenesis, Jin Dai, Yanli Ji, Wei Wang, Donghern Kim, Leonard Yenwong Fai, Lei Wang, Jia Luo, Zhuo Zhang

Toxicology and Cancer Biology Faculty Publications

Hexavalent chromium (Cr(VI)) compounds are confirmed human carcinogens for lung cancer. Our previous studies has demonstrated that chronic exposure of human bronchial epithelial BEAS-2B cells to low dose of Cr(VI) causes malignant cell transformation. The acquisition of cancer stem cell-like properties is involved in the initiation of cancers. The present study has observed that a small population of cancer stem-like cells (BEAS-2B-Cr-CSC) exists in the Cr(VI)-transformed cells (BEAS-2B-Cr). Those BEAS-2B-Cr-CSC exhibit extremely reduced capability of generating reactive oxygen species (ROS) and apoptosis resistance. BEAS-2B-Cr-CSC are metabolic inactive as evidenced by reductions in oxygen consumption, glucose uptake, ATP production, and lactate …

The Role Of Sodium Bicarbonate In The Management Of Some Toxic Ingestions, Aibek E. Mirrakhimov, Taha Ayach, Aram Barbaryan, Goutham Talari, Romil Chadha, Adam Gray

Internal Medicine Faculty Publications

Adverse reactions to commonly prescribed medications and to substances of abuse may result in severe toxicity associated with increased morbidity and mortality. According to the Center for Disease Control, in 2013, at least 2113 human fatalities attributed to poisonings occurred in the United States of America. In this article, we review the data regarding the impact of systemic sodium bicarbonate administration in the management of certain poisonings including sodium channel blocker toxicities, salicylate overdose, and ingestion of some toxic alcohols and in various pharmacological toxicities. Based on the available literature and empiric experience, the administration of sodium bicarbonate appears to …

Clinical And Experimental Studies Of A Novel P525r Fus Mutation In Amyotrophic Lateral Sclerosis, Lisha Kuang, Marisa Kamelgarn, Alexandra Arenas, Jozsef Gal, Deborah Taylor, Weiming Gong, Martin Brown, Daret St. Clair, Edward J. Kasarskis, Haining Zhu

Molecular and Cellular Biochemistry Faculty Publications

Objective: To describe the clinical features of a novel fused in sarcoma (FUS) mutation in a young adult female amyotrophic lateral sclerosis (ALS) patient with rapid progression of weakness and to experimentally validate the consequences of the P525R mutation in cellular neuronal models.

Methods: We conducted sequencing of genomic DNA from the index patient and her family members. Immunocytochemistry was performed in various cellular models to determine whether the newly identified P525R mutant FUS protein accumulated in cytoplasmic inclusions. Clinical features of the index patient were compared with 19 other patients with ALS carrying the P525L mutation in the same …

Multiple Path Particle Dosimetry For Prediction Of Mouse Lung Deposition Of Nanoaerosol Particles, Mohammed Ali

Technology Faculty Publications and Presentations

Nanoaerosolized particle (dia.<200 >nm) antibiotic inhalation therapy was tested to treat pneumonic tularemia in mice caused by Francisella novicida infection. Very limited experimental techniques are available to properly estimate inhaled doses and distribution of the drug inside the mouse lungs. To overcome this problem, computational simulation of particle deposition based on the Multiple Path Particle Dosimetry (MPPD) model was employed to simulate in vivo experimental conditions which included nasal breathing with whole body exposure to the antibiotic in the form of nano-aerosolized medicine. The deposition results were compared with several in vivo experimental data reported in literature; and satisfactory agreements …

Injury-Induced Microvesicle Particle Release In Human Skin Explant Tissue, Katherine E. Fahy, Langni Liu, Christine M. Rapp, Eric J. Romer, Christina E. Borchers, Richard Simman, Ji C. Bihl, Jeffrey B. Travers

Pharmacology and Toxicology Faculty Publications

Microvesicle particles (MVP) are 100-1000 nm vesicles that bud from the cell membrane and transmit intercellular signals locally and systemically via their bioactive cargo (e.g. cytokines).

Injury-Induced Microvesicle Particle Release In Human Skin Explant Tissue, Katherine E. Fahy, Langni Liu, Christina E. Borchers, Richard Simman, Ji C. Bihl, Jeffrey B. Travers

Pharmacology and Toxicology Faculty Publications

Microvesicle particles (MVP) are 100-1000 nm vesicles that bud from the cell membrane and transmit intercellular signals locally and systemically via their bioactive cargo (e.g. cytokines). We have previously shown that thermal burn injury or UVB radiation result in the formation Platelet Activating Factor (PAF), and UVB or a PAF agonist (CPAF) can promote MVP formation in keratinocytes. Thermal burn and UVB radiation can result in systemic effects, even though their injury is localized to the skin. We therefore propose that PAF-producing injuries, UVB irradiation or thermal burn injury, result in the formation of MVPs that can potentially transport cytokines …

Characterization Of A Mutant Oncolytic Adenovirus And The Role Of Jnk In Enhancing Virotherapy., Stephen L. Wechman

Electronic Theses and Dissertations

Oncolytic adenoviruses (Ads) have great therapeutic potential for lung cancer treatment. Cancer selective E1b-deleted Ads are safe; however, their clinical cancer therapeutic efficacy remains limited. The limited efficacy of Ad virotherapy is due to many factors including inefficient cancer cell lysis, Ad release and spread. Progress in overcoming these barriers to Ad virotherapy are hampered by limited knowledge of the genes associated with enhanced Ad release and spread and the dearth of understanding of the mechanisms by which E1b-deleted Ads cause cancer cell lysis. The role of c-JNK n- terminal kinase (JNK) phosphorylation in this process remains unknown. …

The Interaction Of Homoserine Lactones And Paraoxonase 2 Modulates Cell Death Signaling And Cell Proliferation., Aaron Mackallan Neely

Electronic Theses and Dissertations

Pseudomonas aeruginosa produces N-(3-oxododecanoyl)-homoserine lactone (C12) as a quorum-sensing molecule that functions to facilitate bacteria-bacteria communication. C12 has also been reported to affect many aspects of human host cell physiology, including evoking cell death in various types of cells. However, the signaling pathway(s) leading to C12-triggerred cell death remains unclear. To clarify cell death signaling induced by C12, we examined mouse embryonic fibroblasts (MEFs) deficient in one or more caspases. Our data indicate that, unlike most apoptotic inducers, C12 evokes a novel form of apoptosis in cells, probably through the direct induction of mitochondrial membrane permeabilization. Importantly, C12 induces apoptosis …

The Effects Of Moderate Alcohol Consumption And Inflammation On The Hepatic Matrisome And The Renal Cortex Proteome., Christine E. Dolin

Electronic Theses and Dissertations

Background. The association of chronic ethanol (EtOH) consumption with extracellular matrix (ECM) changes in alcoholic liver disease (ALD) is well established in the context of hepatic fibrosis. However, it is becoming increasingly understood that the hepatic ECM responds dynamically to stress well before fibrosis. The term “transitional tissue remodeling” describes qualitative and quantitative ECM changes in response to injury that do not alter the overall architecture of the organ; these ECM changes may contribute to early disease initiation and/or progression. The nature and magnitude of these changes to the ECM are currently poorly understood. In contrast to the liver, EtOH …

Melatonin And Its Metabolites Protect Human Melanocytes Against Uvb-Induced Damage: Involvement Of Nrf2-Mediated Pathways, Zorica Janjetovic, Stuart G. Jarrett, Elizabeth F. Lee, Cory Duprey, Russel J. Reiter, Andrzej T. Slominski

Toxicology and Cancer Biology Faculty Publications

Ultraviolet light (UV) is an inducer of reactive oxygen species (ROS) as well as 6-4-photoproducts and cyclobutane pyrimidine dimers (CPD) in the skin, which further cause damage to the skin cells. Irradiation of cultured human melanocytes with UVB stimulated ROS production, which was reduced in cells treated with melatonin or its metabolites: 6-hydroxymelatonin (6-OHM), N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK), N-acetylserotonin (NAS), and 5-methoxytryptamine (5-MT). Melatonin and its derivatives also stimulated the expression of NRF2 (nuclear factor erythroid 2 [NF-E2]-related factor 2) and its target enzymes and proteins that play an important role in cell protection from different damaging factors including UVB. Silencing …

Lkb1 Inactivation Drives Lung Cancer Lineage Switching Governed By Polycomb Repressive Complex 2, Haikuo Zhang, Christine Fillmore Brainson, Shohei Koyama, Amanda J. Redig, Ting Chen, Shuai Li, Manav Gupta, Carolina Garcia-De-Alba, Margherita Paschini, Grit S. Herter-Sprie, Gang Lu, Xin Zhang, Bryan P. Marsh, Stephanie J. Tuminello, Chunxiao Xu, Zhao Chen, Xiaoen Wang, Esra A. Akbay, Mei Zheng, Sangeetha Palakurthi, Lynette M. Sholl, Anil K. Rustgi, David J. Kwiatkowski, J. Alan Diehl, Adam J. Bass, Norman E. Sharpless, Glenn Dranoff, Peter S. Hammerman, Hongbin Ji, Nabeel Bardeesy, Dieter Saur, Hideo Watanabe, Carla F. Kim, Kwok-Kin Wong

Toxicology and Cancer Biology Faculty Publications

Adenosquamous lung tumours, which are extremely poor prognosis, may result from cellular plasticity. Here, we demonstrate lineage switching of KRAS+ lung adenocarcinomas (ADC) to squamous cell carcinoma (SCC) through deletion of Lkb1 (Stk11) in autochthonous and transplant models. Chromatin analysis reveals loss of H3K27me3 and gain of H3K27ac and H3K4me3 at squamous lineage genes, including Sox2, ΔNp63 and Ngfr. SCC lesions have higher levels of the H3K27 methyltransferase EZH2 than the ADC lesions, but there is a clear lack of the essential Polycomb Repressive Complex 2 (PRC2) subunit EED in the SCC lesions. The pattern of high EZH2, but …

Glioma Stem Cells-Derived Exosomes Promote The Angiogenic Ability Of Endothelial Cells Through Mir-21/Vegf Signal, Xu Sun, Xiaotang Ma, Jinju Wang, Yuhui Zhao, Yue Wang, Ji C. Bihl, Yanfang Chen, Chuanlu Jiang

Pharmacology and Toxicology Faculty Publications

Glioma stem cells (GSCs) play an important role in glioblastoma prognosis. Exosomes (EXs) mediate cell communication by delivering microRNAs (miRs). Glioblastoma has a high level of miR-21 which could upregulate vascular endothelial growth factor (VEGF) expression. We hypothesized GSC-EXs can promote the angiogenic ability of endothelial cells (ECs) through miR-21/VEGF signal. GSCs were isolated from U-251 cells with stem cell marker CD133. GSCs transfected without or with scramble or miR-21 mimics were used to produce GSC-^EXscon, GSC-EXs^sc and GSC-EXs^miR-21. Human brain ECs were co-cultured with vehicle, GSC-EXs^con, GSC-EXs^sc or GSC-EXs^miR-21 plus …