Medical Toxicology Commons^™

Latexin Inactivation Enhances Survival And Long-Term Engraftment Of Hematopoietic Stem Cells And Expands The Entire Hematopoietic System In Mice, Yi Liu, Cuiping Zhang, Zhenyu Li, Chi Wang, Jianhang Jia, Tianyan Gao, Gerhard C. Hildebrandt, Daohong Zhou, Subbarao Bondada, Peng Ji, Daret K. St. Clair, Jinze Liu, Chang-Guo Zhan, Hartmut Geiger, Shuxia Wang, Ying Liang

Toxicology and Cancer Biology Faculty Publications

Natural genetic diversity offers an important yet largely untapped resource to decipher the molecular mechanisms regulating hematopoietic stem cell (HSC) function. Latexin (Lxn) is a negative stem cell regulatory gene identified on the basis of genetic diversity. By using an Lxn knockout mouse model, we found that Lxn inactivation in vivo led to the physiological expansion of the entire hematopoietic hierarchy. Loss of Lxn enhanced the competitive repopulation capacity and survival of HSCs in a cell-intrinsic manner. Gene profiling of Lxn-null HSCs showed altered expression of genes enriched in cell-matrix and cell-cell interactions. Thrombospondin 1 (Thbs1 …

Relb Expression Determines The Differential Effects Of Ascorbic Acid In Normal And Cancer Cells, Xiaowei Wei, Yong Xu, Fang Fang Xu, Luksana Chaiswing, David M. Schnell, Teresa Noel, Chi Wang, Jinfei Chen, Daret K. St. Clair, William H. St. Clair

Toxicology and Cancer Biology Faculty Publications

Cancer cells typically experience higher oxidative stress than normal cells, such that elevating pro-oxidant levels can trigger cancer cell death. Although pre-exposure to mild oxidative agents will sensitize cancer cells to radiation, this pre-exposure may also activate the adaptive stress defense system in normal cells. Ascorbic acid is a prototype redox modulator that when infused intravenously appears to kill cancers without injury to normal tissues; however, the mechanisms involved remain elusive. In this study, we show how ascorbic acid kills cancer cells and sensitizes prostate cancer to radiation therapy while also conferring protection upon normal prostate epithelial cells against radiation-induced …

A Novel Redox Regulator, Mntnbuoe-2-Pyp5+, Enhances Normal Hematopoietic Stem/Progenitor Cell Function, Yanming Zhao, Dustin W. Carroll, Y. You, Luksana Chaiswing, R. Wen, I. Batinic-Haberle, Subbarao Bondada, Ying Liang, Daret K. St Clair

Toxicology and Cancer Biology Faculty Publications

The signaling of reactive oxygen species (ROS) is essential for the maintenance of normal cellular function. However, whether and how ROS regulate stem cells are unclear. Here, we demonstrate that, in transgenic mice expressing the human manganese superoxide dismutase (MnSOD) gene, a scavenger of ROS in mitochondria, the number and function of mouse hematopoietic stem/progenitor cells (HSPC) under physiological conditions are enhanced. Importantly, giving MnTnBuOE-2-PyP⁵⁺(MnP), a redox- active MnSOD mimetic, to mouse primary bone marrow cells or to C57B/L6 mice significantly enhances the number of HSPCs. Mechanistically, MnP reduces superoxide to hydrogen peroxide, which activates intracellular Nrf2 signaling …

Polyubiquitination Of Apurinic/Apyrimidinic Endonuclease 1 By Parkin, Timothy L. Scott, Christina A. Wicker, Rangaswamy Suganya, Bithika Dhar, Thomas A. Pittman, Craig Horbinski, Tadahide Izumi

Toxicology and Cancer Biology Faculty Publications

Apurinic/apyrimidinic endonuclease 1 (APE1) is an essential protein crucial for repair of oxidized DNA damage not only in genomic DNA but also in mitochondrial DNA. Parkin, a tumor suppressor and Parkinson's disease (PD) associated gene, is an E3 ubiquitin ligase crucial for mitophagy. Although DNA damage is known to induce mitochondrial stress, Parkin's role in regulating DNA repair proteins has not been elucidated. In this study, we examined the possibility of Parkin‐dependent ubiquitination of APE1. Ectopically expressed APE1 was degraded by Parkin and PINK1 via polyubiquitination in mouse embryonic fibroblast cells. PD‐causing mutations in Parkin and PINK1 abrogated APE1 ubiquitination. …

Changes In Mitochondrial Homeostasis And Redox Status In Astronauts Following Long Stays In Space, Hiroko P. Indo, Hideyuki J. Majima, Masahiro Terada, Shigeaki Suenaga, Kazuo Tomita, Shin Yamada, Akira Higashibata, Noriaki Ishioka, Takuro Kanekura, Ikuya Nonaka, Clare L. Hawkins, Michael J. Davies, Daret K. St Clair, Chiaki Mukai

Toxicology and Cancer Biology Faculty Publications

The effects of long-term exposure to extreme space conditions on astronauts were investigated by analyzing hair samples from ten astronauts who had spent six months on the International Space Station (ISS). Two samples were collected before, during and after their stays in the ISS; hereafter, referred to as Preflight, Inflight and Postflight, respectively. The ratios of mitochondrial (mt) to nuclear (n) DNA and mtRNA to nRNA were analyzed via quantitative PCR. The combined data of Preflight, Inflight and Postflight show a significant reduction in the mtDNA/nDNA in Inflight, and significant reductions in the mtRNA/nRNA ratios in both the Inflight and …

Analysis Of Rna Expression Of Normal And Cancer Tissues Reveals High Correlation Of Cop9 Gene Expression With Respiratory Chain Complex Components, Christina A. Wicker, Tadahide Izumi

Toxicology and Cancer Biology Faculty Publications

BACKGROUND: The COP9 signalosome, composed of eight subunits, is implicated in cancer genetics with its deneddylase activity to modulate cellular concentration of oncogenic proteins such as IkB and TGFβ. However, its function in the normal cell physiology remains elusive. Primarily focusing on gene expression data of the normal tissues of the head and neck, the cancer genome atlas (TCGA) database was used to identify groups of genes that were expressed synergistically with the COP9 genes, particularly with the COPS5 (CSN5), which possesses the catalytic activity of COP9.

RESULTS: Expressions of seven of the COP9 genes (COPS2, COPS3, COPS4, COPS5, COPS6, …

Simultaneous Quantitation Of Oxidized And Reduced Glutathione Via Lc-Ms/Ms: An Insight Into The Redox State Of Hematopoietic Stem Cells, Dustin W. Carroll, Diana Howard, Haining Zhu, Christian M. Paumi, Mary Vore, Subbarao Bondada, Ying Liang, Chi Wang, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

Cellular redox balance plays a significant role in the regulation of hematopoietic stem-progenitor cell (HSC/MPP) self-renewal and differentiation. Unregulated changes in cellular redox homeostasis are associated with the onset of most hematological disorders. However, accurate measurement of the redox state in stem cells is difficult because of the scarcity of HSC/MPPs. Glutathione (GSH) constitutes the most abundant pool of cellular antioxidants. Thus, GSH metabolism may play a critical role in hematological disease onset and progression. A major limitation to studying GSH metabolism in HSC/MPPs has been the inability to measure quantitatively GSH concentrations in small numbers of HSC/MPPs. Current methods …

Exposure Of Human Lung Cells To Tobacco Smoke Condensate Inhibits The Nucleotide Excision Repair Pathway, Nathaniel C. Holcomb, Mamta Goswami, Sung Gu Han, Samuel Clark, David K. Orren, C. Gary Gairola, Isabel Mellon

Toxicology and Cancer Biology Faculty Publications

Exposure to tobacco smoke is the number one risk factor for lung cancer. Although the DNA damaging properties of tobacco smoke have been well documented, relatively few studies have examined its effect on DNA repair pathways. This is especially true for the nucleotide excision repair (NER) pathway which recognizes and removes many structurally diverse DNA lesions, including those introduced by chemical carcinogens present in tobacco smoke. The aim of the present study was to investigate the effect of tobacco smoke on NER in human lung cells. We studied the effect of cigarette smoke condensate (CSC), a surrogate for tobacco smoke, …

Ubiquitin-Specific Peptidase 10 (Usp10) Deubiquitinates And Stabilizes Muts Homolog 2 (Msh2) To Regulate Cellular Sensitivity To Dna Damage, Mu Zhang, Chen Hu, Dan Tong, Shengyan Xiang, Kendra Williams, Wenlong Bai, Guo-Min Li, Gerold Bepler, Xiaohong Zhang

Toxicology and Cancer Biology Faculty Publications

MSH2 is a key DNA mismatch repair protein, which plays an important role in genomic stability. In addition to its DNA repair function, MSH2 serves as a sensor for DNA base analogs-provoked DNA replication errors and binds to various DNA damage-induced adducts to trigger cell cycle arrest or apoptosis. Loss or depletion of MSH2 from cells renders resistance to certain DNA-damaging agents. Therefore, the level of MSH2 determines DNA damage response. Previous studies showed that the level of MSH2 protein is modulated by the ubiquitin-proteasome pathway, and histone deacetylase 6 (HDAC6) serves as an ubiquitin E3 ligase. However, the deubiquitinating …

Stable Isotope Resolved Metabolomics Studies In Ex Vivo Tissue Slices, Teresa W-M Fan, Andrew N. Lane, Richard M. Higashi

Toxicology and Cancer Biology Faculty Publications

An important component of this methodology is to assess the role of the tumor microenvironment on tumor growth and survival. To tackle this problem, we have adapted the original approach of Warburg (Warburg, 1923), by combining thin tissue slices with Stable Isotope Resolved Metabolomics (SIRM) to determine detailed metabolic activity of human tissues. SIRM enables the tracing of metabolic transformations of source molecules such as glucose or glutamine over defined time periods, and is a requirement for detailed pathway tracing and flux analysis. In our approach, we maintain freshly resected tissue slices (both cancerous and non- cancerous from the same …

H2ax Deficiency Is Associated With Erythroid Dysplasia And Compromised Haematopoietic Stem Cell Function, Baobing Zhao, Timothy L. Tan, Yang Mei, Jing Yang, Yiting Yu, Amit Verma, Ying Liang, Juehua Gao, Peng Ji

Toxicology and Cancer Biology Faculty Publications

Myelodysplastic syndromes (MDS) are clonal disorders of haematopoiesis characterised by dysplastic changes of major myeloid cell lines. However, the mechanisms underlying these dysplastic changes are poorly understood. Here, we used a genetically modified mouse model and human patient data to examine the physiological roles of H2AX in haematopoiesis and how the loss of H2AX contributes to dyserythropoiesis in MDS. H2AX knockout mice showed cell-autonomous anaemia and erythroid dysplasia, mimicking dyserythropoiesis in MDS. Also, dyserythropoiesis was increased in MDS patients with the deletion of chromosome 11q23, where H2AX is located. Although loss of H2AX did not affect the early stage of …

Metabolomics Workbench: An International Repository For Metabolomics Data And Metadata, Metabolite Standards, Protocols, Tutorials And Training, And Analysis Tools, Manish Sud, Eoin Fahy, Dawn Cotter, Kenan Azam, Ilango Vadivelu, Charles Burant, Arthur Edison, Oliver Fiehn, Richard M. Higashi, K. Sreekumaran Nair, Susan Sumner, Shankar Subramaniam

Toxicology and Cancer Biology Faculty Publications

The Metabolomics Workbench, available at www.metabolomicsworkbench.org, is a public repository for metabolomics metadata and experimental data spanning various species and experimental platforms, metabolite standards, metabolite structures, protocols, tutorials, and training material and other educational resources. It provides a computational platform to integrate, analyze, track, deposit and disseminate large volumes of heterogeneous data from a wide variety of metabolomics studies including mass spectrometry (MS) and nuclear magnetic resonance spectrometry (NMR) data spanning over 20 different species covering all the major taxonomic categories including humans and other mammals, plants, insects, invertebrates and microorganisms. Additionally, a number of protocols are provided for …

The Nobel Prize In Chemistry 2015: Exciting Discoveries In Dna Repair By Aziz Sancar, David K. Orren

Toxicology and Cancer Biology Faculty Publications

On October 7, 2015, the Nobel Prize in Chemistry for 2015 was awarded to three deserving scientists for their pioneering research on DNA repair. Tomas Lindahl was recognized for studies that uncovered the inherent instability of DNA as well as the mechanism of the base excision repair pathway, Paul Modrich for characterization of the mismatch repair pathway, and Aziz Sancar for mechanistic elucidation of the nucleotide excision repair (NER) pathway. For me, the announcement of these awards in my area of research was extremely gratifying, particularly so because Aziz was my mentor during my Ph.D. studies that examined the steps …

Methylseleninic Acid Promotes Antitumour Effects Via Nuclear Foxo3a Translocation Through Akt Inhibition, Míriam Tarrado-Castellarnau, Roldán Cortés, Miriam Zanuy, Josep Tarragó-Celada, Ibrahim H. Polat, Richard Hill, Teresa W-M Fan, Wolfgang Link, Marta Cascante

Toxicology and Cancer Biology Faculty Publications

Selenium supplement has been shown in clinical trials to reduce the risk of different cancers including lung carcinoma. Previous studies reported that the antiproliferative and pro-apoptotic activities of methylseleninic acid (MSA) in cancer cells could be mediated by inhibition of the PI3K pathway. A better understanding of the downstream cellular targets of MSA will provide information on its mechanism of action and will help to optimize its use in combination therapies with PI3K inhibitors. For this study, the effects of MSA on viability, cell cycle, metabolism, apoptosis, protein and mRNA expression, and reactive oxygen species production were analysed in A549 …

13C Tracer Studies Of Metabolism In Mouse Tumor Xenografts, Andrew N. Lane, Jun Yan, Teresa W-M Fan

Toxicology and Cancer Biology Faculty Publications

Mice are widely used for human tumor xenograft studies of cancer development and drug efficacy and toxicity. Stable isotope tracing coupled with metabolomic analysis is an emerging approach for assaying metabolic network activity. In mouse models there are several routes of tracer introduction, which have particular advantages and disadvantages that depend on the model and the questions addressed. This protocol describes the bolus i.v. route via repeated tail vein injections of solutions of stable isotope enriched tracers including ¹³C₆-glucose and ¹³C₅,¹⁵N₂-glutamine. Repeated injections give higher enrichments and over longer labeling …

Phytochemicals In Cancer Prevention And Therapy, Poyil Pratheeshkumar, Young-Ok Son, Preethi Korangath, Kanjoormana Aryan Manu, Kodappully Sivaraman Siveen

Toxicology and Cancer Biology Faculty Publications

Despite advances in modern medicine, cancer is still the major cause of mortality in both developing and developed countries. Search for safer and more effective chemoprevention and treatment strategy is a need for the improvement of patient care in the field. Prevention may be more effective and less costly because cancer is largely a preventable disease which could be attributed to a greater extent to lifestyle. Dietary phytochemicals have been used for the treatment of cancer throughout history due to their safety, low toxicity, and general availability. Population based studies suggest that a reduced risk of cancer is associated with …

The Dna Structure And Sequence Preferences Of Wrn Underlie Its Function In Telomeric Recombination Events, Deanna N. Edwards, Amrita Machwe, Li Chen, Vilhelm A. Bohr, David K. Orren

Toxicology and Cancer Biology Faculty Publications

Telomeric abnormalities caused by loss of function of the RecQ helicase WRN are linked to the multiple premature ageing phenotypes that characterize Werner syndrome. Here we examine WRN's role in telomeric maintenance, by comparing its action on a variety of DNA structures without or with telomeric sequences. Our results show that WRN clearly prefers to act on strand invasion intermediates in a manner that favours strand invasion and exchange. Moreover, WRN unwinding of these recombination structures is further enhanced when the invading strand contains at least three G-rich single-stranded telomeric repeats. These selectivities are most pronounced at NaCl concentrations within …

The C-Terminal Domain (Ctd) Of Human Dna Glycosylaseneil1 Is Required For Forming Berosome Repair Complex With Dna Replication Proteins At The Replicating Genome: Dominant Negative Function Of The Ctd, Pavana M. Hegde, Arijit Dutta, Shiladitya Sengupta, Joy Mitra, Sanjay Adhikari, Alan E. Tomkinson, Guo-Min Li, Istvan Boldogh, Tapas K. Hazra, Sankar Mitra, Muralidhar L. Hegde

Toxicology and Cancer Biology Faculty Publications

The human DNA glycosylase NEIL1 was recently demonstrated to initiate prereplicative base excision repair (BER) of oxidized bases in the replicating genome, thus preventing mutagenic replication. A significant fraction of NEIL1 in cells is present in large cellular complexes containing DNA replication and other repair proteins, as shown by gel filtration. However, how the interaction of NEIL1 affects its recruitment to the replication site for prereplicative repair was not investigated. Here, we show that NEIL1 binarily interacts with the proliferating cell nuclear antigen clamp loader replication factor C, DNA polymerase δ, and DNA ligase I in the absence of DNA …

Truncating Mutation In The Autophagy Gene Uvrag Confers Oncogenic Properties And Chemosensitivity In Colorectal Cancers, Shanshan He, Zhen Zhao, Yongfei Yang, Douglas O'Connell, Xiaowei Zhang, Soohwan Oh, Binyun Ma, Joo-Hyung Lee, Tian Zhang, Bino Varghese, Janae Yip, Sara Dolatshahi Pirooz, Ming Li, Yong Zhang, Guo-Min Li, Sue Ellen Martin, Keigo Machida, Chengyu Liang

Toxicology and Cancer Biology Faculty Publications

Autophagy-related factors are implicated in metabolic adaptation and cancer metastasis. However, the role of autophagy factors in cancer progression and their effect in treatment response remain largely elusive. Recent studies have shown that UVRAG, a key autophagic tumour suppressor, is mutated in common human cancers. Here we demonstrate that the cancer-related UVRAG frameshift (FS), which does not result in a null mutation, is expressed as a truncated UVRAG^FS in colorectal cancer (CRC) with microsatellite instability (MSI), and promotes tumorigenesis. UVRAG^FS abrogates the normal functions of UVRAG, including autophagy, in a dominant-negative manner. Furthermore, expression of UVRAG^FS can …

A Genetic Porcine Model Of Cancer, Lawrence B. Schook, Tiago V. Collares, Wenping Hu, Ying Liang, Fernanda M. Rodrigues, Laurie A. Rund, Kyle M. Schachtschneider, Fabiana K. Seixas, Kuldeep Singh, Kevin D. Wells, Eric M. Walters, Randall S. Prather, Christopher M. Counter

Toxicology and Cancer Biology Faculty Publications

The large size of the pig and its similarity in anatomy, physiology, metabolism, and genetics to humans make it an ideal platform to develop a genetically defined, large animal model of cancer. To this end, we created a transgenic "oncopig" line encoding Cre recombinase inducible porcine transgenes encoding KRAS^G12D and TP^53R167H, which represent a commonly mutated oncogene and tumor suppressor in human cancers, respectively. Treatment of cells derived from these oncopigs with the adenovirus encoding Cre (AdCre) led to KRAS^G12D and TP^53R167H expression, which rendered the cells transformed in culture and tumorigenic when engrafted into …

Arsenic Inhibits Dna Mismatch Repair By Promoting Egfr Expression And Pcna Phosphorylation, Dan Tong, Janice Ortega, Christine Kim, Jian Huang, Liya Gu, Guo-Min Li

Toxicology and Cancer Biology Faculty Publications

Both genotoxic and non-genotoxic chemicals can act as carcinogens. However, while genotoxic compounds lead directly to mutations that promote unregulated cell growth, the mechanism by which non-genotoxic carcinogens lead to cellular transformation is poorly understood. Using a model non-genotoxic carcinogen, arsenic, we show here that exposure to arsenic inhibits mismatch repair (MMR) in human cells, possibly through its ability to stimulate epidermal growth factor receptor (EGFR)-dependent tyrosine phosphorylation of proliferating cellular nuclear antigen (PCNA). HeLa cells exposed to exogenous arsenic demonstrate a dose- and time-dependent increase in the levels of EGFR and tyrosine 211-phosphorylated PCNA. Cell extracts derived from arsenic-treated …

Human Dna Exonuclease Trex1 Is Also An Exoribonuclease That Acts On Single-Stranded Rna, Fenghua Yuan, Tanmay Dutta, Ling Wang, Lei Song, Liya Gu, Liangyue Qian, Anaid Benitez, Shunbin Ning, Arun Malhotra, Murray P. Deutscher, Yanbin Zhang

Toxicology and Cancer Biology Faculty Publications

3' repair exonuclease 1 (TREX1) is a known DNA exonuclease involved in autoimmune disorders and the antiviral response. In this work, we show that TREX1 is also a RNA exonuclease. Purified TREX1 displays robust exoribonuclease activity that degrades single-stranded, but not double-stranded, RNA. TREX1-D200N, an Aicardi-Goutieres syndrome disease-causing mutant, is defective in degrading RNA. TREX1 activity is strongly inhibited by a stretch of pyrimidine residues as is a bacterial homolog, RNase T. Kinetic measurements indicate that the apparent K_m of TREX1 for RNA is higher than that for DNA. Like RNase T, human TREX1 is active in degrading native …

Chemoselective Detection And Discrimination Of Carbonyl-Containing Compounds In Metabolite Mixtures By 1H-Detected 15N Nuclear Magnetic Resonance, Andrew N. Lane, Sengodagounder Arumugam, Pawel Lorkiewicz, Richard M. Higashi, Sébastien Laulhé, Michael H. Nantz, Hunter N. B. Moseley, Teresa W-M Fan

Toxicology and Cancer Biology Faculty Publications

NMR spectra of mixtures of metabolites extracted from cells or tissues are extremely complex, reflecting the large number of compounds that are present over a wide range of concentrations. Although multidimensional NMR can greatly improve resolution as well as improve reliability of compound assignments, lower abundance metabolites often remain hidden. We have developed a carbonyl-selective aminooxy probe that specifically reacts with free keto and aldehyde functions, but not carboxylates. By incorporating ¹⁵N in the aminooxy functional group, ¹⁵N-edited NMR was used to select exclusively those metabolites that contain a free carbonyl function while all other metabolites are rejected. …

Regulation Of Mammalian Nucleotide Metabolism And Biosynthesis, Andrew N. Lane, Teresa W-M Fan

Toxicology and Cancer Biology Faculty Publications

Nucleotides are required for a wide variety of biological processes and are constantly synthesized de novo in all cells. When cells proliferate, increased nucleotide synthesis is necessary for DNA replication and for RNA production to support protein synthesis at different stages of the cell cycle, during which these events are regulated at multiple levels. Therefore the synthesis of the precursor nucleotides is also strongly regulated at multiple levels. Nucleotide synthesis is an energy intensive process that uses multiple metabolic pathways across different cell compartments and several sources of carbon and nitrogen. The processes are regulated at the transcription level by …

Pyruvate Carboxylase Is Critical For Non-Small-Cell Lung Cancer Proliferation, Katherine Sellers, Matthew P. Fox, Michael Bousamra Ii, Stephen P. Slone, Richard M. Higashi, Donald M. Miller, Yali Wang, Jun Yan, Mariia O. Yuneva, Rahul Deshpande, Andrew N. Lane, Teresa W-M Fan

Toxicology and Cancer Biology Faculty Publications

Anabolic biosynthesis requires precursors supplied by the Krebs cycle, which in turn requires anaplerosis to replenish precursor intermediates. The major anaplerotic sources are pyruvate and glutamine, which require the activity of pyruvate carboxylase (PC) and glutaminase 1 (GLS1), respectively. Due to their rapid proliferation, cancer cells have increased anabolic and energy demands; however, different cancer cell types exhibit differential requirements for PC- and GLS-mediated pathways for anaplerosis and cell proliferation. Here, we infused patients with early-stage non-small-cell lung cancer (NSCLC) with uniformly 13C-labeled glucose before tissue resection and determined that the cancerous tissues in these patients had enhanced PC activity. …

Latexin Sensitizes Leukemogenic Cells To Gamma-Irradiation-Induced Cell-Cycle Arrest And Cell Death Through Rps3 Pathway, Y. You, R. Wen, R. Pathak, A. Li, W. Li, D. St. Clair, M. Hauer-Jensen, D. Zhou, Ying Liang

Toxicology and Cancer Biology Faculty Publications

Leukemia is a leading cause of cancer death. Recently, the latexin (Lxn) gene was identified as a potential tumor suppressor in several types of solid tumors and lymphoma, and Lxn expression was found to be absent or downregulated in leukemic cells. Whether Lxn functions as a tumor suppressor in leukemia and what molecular and cellular mechanisms are involved are unknown. In this study, the myeloid leukemogenic FDC-P1 cell line was used as a model system and Lxn was ectopically expressed in these cells. Using the protein pull-down assay and mass spectrometry, ribosomal protein subunit 3 (Rps3) was identified as a …

Expression Of Peroxiredoxin 1 And 4 Promotes Human Lung Cancer Malignancy, Hong Jiang, Lisha Wu, Murli Mishra, Hedy A. Chawsheen, Qiou Wei

Toxicology and Cancer Biology Faculty Publications

Members of the Peroxiredoxin (Prx) family are major cellular antioxidants that scavenge hydrogen peroxide and play essential roles in oxidative stress and cell signaling. 2-Cys Prxs, including Prx1, 2, 3 and 4, have been indicated in multiple oncogenic signaling pathways and thus may contribute to various processes of cancer development. The significance of 2-Cys Prxs in lung cancer development and their biological function in signal transduction have not been fully investigated. In this study we analyzed the expression of 2-Cys Prxs in lung cancer, and examined their levels of expression in a variety of cell lines established from human lung …

Redox Proteomic Identification Of Hne-Bound Mitochondrial Proteins In Cardiac Tissues Reveals A Systemic Effect On Energy Metabolism After Doxorubicin Treatment, Y. Zhao, Sumitra Miriyala, L. Miao, Mihail I. Mitov, David M. Schnell, Sanjit Kumar Dhar, J. Cai, J. B. Klein, Rukhsana Sultana, D. Allan Butterfield, Mary Vore, I. Batinic-Haberle, Subbarao Bondada, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

Doxorubicin (DOX), one of the most effective anticancer drugs, is known to generate progressive cardiac damage, which is due, in part, to DOX-induced reactive oxygen species (ROS). The elevated ROS often induce oxidative protein modifications that result in alteration of protein functions. This study demonstrates that the level of proteins adducted by 4-hydroxy-2-nonenal (HNE), a lipid peroxidation product, is significantly increased in mouse heart mitochondria after DOX treatment. A redox proteomics method involving two-dimensional electrophoresis followed by mass spectrometry and investigation of protein databases identified several HNE-modified mitochondrial proteins, which were verified by HNE-specific immunoprecipitation in cardiac mitochondria from the …

Profiling Thiol Metabolites And Quantification Of Cellular Glutathione Using Ft-Icr-Ms Spectrometry, Sadakatali S. Gori, Pawel Lorkiewicz, Daniel S. Ehringer, Alex C. Belshoff, Richard M. Higashi, Teresa W-M Fan, Michael H. Nantz

Toxicology and Cancer Biology Faculty Publications

We describe preparation and use of the quaternary ammonium-based α-iodoacetamide QDE and its isotopologue *QDE as reagents for chemoselective derivatization of cellular thiols. Direct addition of the reagents to live cells followed by adduct extraction into n-butanol and analysis by FT-ICR-MS provided a registry of matched isotope peaks from which molecular formulae of thiol metabolites were derived. Acidification to pH 4 during cell lysis and adduct formation further improves the chemoselectivity for thiol derivatization. Examination of A549 human lung adenocarcinoma cells using this approach revealed cysteine, cysteinylglycine, glutathione, and homocysteine as principal thiol metabolites as well as the sulfinic acid …

Targeting Lactate Dehydrogenase-A Inhibits Tumorigenesis And Tumor Progression In Mouse Models Of Lung Cancer And Impacts Tumor-Initiating Cells, Han Xie, Jun-Ichi Hanai, Jian-Guo Ren, Lev Kats, Kerri Burgess, Parul Bhargava, Sabina Signoretti, Julia Billiard, Kevin J. Duffy, Aaron Grant, Xiaoen Wang, Pawel Lorkiewicz, Sabrina Schatzman, Michael Bousamra, Andrew N. Lane, Richard M. Higashi, Teresa W-M Fan, Pier Paolo Pandolfi, Vikas P. Sukhatme, Pankaj Seth

Toxicology and Cancer Biology Faculty Publications

The lactate dehydrogenase-A (LDH-A) enzyme catalyzes the interconversion of pyruvate and lactate, is upregulated in human cancers, and is associated with aggressive tumor outcomes. Here we use an inducible murine model and demonstrate that inactivation of LDH-A in mouse models of NSCLC driven by oncogenic K-RAS or EGFR leads to decreased tumorigenesis and disease regression in established tumors. We also show that abrogation of LDH-A results in reprogramming of pyruvate metabolism, with decreased lactic fermentation in vitro, in vivo, and ex vivo. This was accompanied by reactivation of mitochondrial function in vitro, but not in vivo …