Medicine and Health Sciences Commons^™

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 …

Ngo's Bpa Report Intended To Frighten, Not Enlighten., Robert L. Brent Dr.

The Selected Works of Robert Brent

None

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 …

Characterization Of The Nicotine-Induced Endoplasmic Reticulum Stress Response In The Rat Placenta In Vivo And In Vitro, Michael Ka Chun Wong

Electronic Thesis and Dissertation Repository

Nicotine exposure during pregnancy leads to adverse health outcomes, including compromised placental development. Although the molecular mechanisms remain elusive, recent studies identified that endoplasmic reticulum (ER) stress may underlie poor placentation. Therefore, we were interested in investigating the effects of nicotine exposure on the ER stress response in the placenta. A well-established maternal nicotine exposure rat model and Rcho-1 trophoblast giant cell model were utilized to address the research questions. Maternal nicotine exposure in vivo led to elevated ER stress in association with impaired disulfide bond formation and hypoxia. Nicotine exposure in vitro further differentiated that ER stress may be …

Modern Study Of Environmental Pollution From The Emission Of Alpha Particles In Human Blood Samples In The City Of Najaf, Iraq, Basim A. Almayahi

21st International Conference on Environmental Indicators (ICEI 2015)

No abstract provided.

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 …

Antidepressant Effects In Hybrid Striped Bass: Moving From External Exposures To Internal Doses, Lauren Sweet

All Dissertations

Over 47 percent of Americans take at least one prescription drug per month and of these pharmaceuticals, antidepressants are the third most prescribed drug. Their widespread and prolonged use coupled with incomplete removal during wastewater treatment processes has made them one of the most commonly detected pharmaceuticals in the aquatic environment. Antidepressants are intended to modify human behavior by altering brain chemistry and the neurotransmitter receptor targets of these chemicals are highly conserved in many vertebrate species; thus, aquatic organisms may be at risk. Previous research in our lab has shown that exposure of hybrid striped bass (HSB) (Morone saxatilis …

Regulated Phosphorylation Of The K-Cl Cotransporter Kcc3 Is A Molecular Switch Of Intracellular Potassium Content And Cell Volume Homeostasis, Norma C. Adragna, Nagendra B. Ravilla, Peter K. Lauf, Gulnaz Begum, Arjun R. Khanna, Dandan Sun, Kristopher K. Kahle

Pharmacology and Toxicology Faculty Publications

The defense of cell volume against excessive shrinkage or swelling is a requirement for cell function and organismal survival. Cell swelling triggers a coordinated homeostatic response termed regulatory volume decrease (RVD), resulting in K+ and Cl− efflux via activation of K+ channels, volume-regulated anion channels (VRACs), and the K+-Cl− cotransporters, including KCC3. Here, we show genetic alanine (Ala) substitution at threonines (Thr) 991 and 1048 in the KCC3a isoform carboxyl-terminus, preventing inhibitory phosphorylation at these sites, not only significantly up-regulates KCC3a activity up to 25-fold in normally inhibitory isotonic conditions, but is also accompanied by reversal of activity of the …

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 …

Prepubertal Organochlorine Pesticide Concentrations And Age Of Pubertal Onset Among Russian Boys, Thuy Lam, Paige Williams, Mary Lee, Susan Korrick, Linda Birnbaum, Jane Burns, Oleg Sergeyev, Boris Revich, Larisa Altshul, Donald Patterson, Wayman Turner, Russ Hauser

Mary M. Lee

BACKGROUND: In animal studies, organochlorine pesticide (OCP) exposure alters pubertal development; however, epidemiological data are limited and inconsistent. OBJECTIVE: To evaluate the associations of serum OCP concentrations [hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE)] with male pubertal onset. METHODS: In Chapaevsk, Russia, a town environmentally contaminated with OCPs, 350 8-9 year old boys with measured OCPs were enrolled during 2003-2005 and were followed annually for eight years. We evaluated three measures of pubertal onset: testicular volume (TV) > 3 mL in either testis, or stage 2 or greater for genitalia (G2+), or pubic hair (P2+). We used multivariable interval-censored models to …

Association Between Chlorinated Pesticides In The Serum Of Prepubertal Russian Boys And Longitudinal Biomarkers Of Metabolic Function, Jane Burns, Paige Williams, Susan Korrick, Russ Hauser, Oleg Sergeyev, Boris Revich, Thuy Lam, Mary Lee

Mary M. Lee

Organochlorine pesticides (OCPs) have been linked to adult metabolic disorders; however, few studies have examined these associations in childhood. We prospectively evaluated the associations of baseline serum OCPs (hexachlorobenzene, beta-hexachlorocyclohexane, and p,p'-dichlorodiphenyldichloroethylene) in Russian boys with subsequent repeated measurements of serum glucose, insulin, lipids, leptin, and calculated homeostatic model assessment of insulin resistance (IR). During 2003-2005, we enrolled 499 boys aged 8-9 years in a prospective cohort; 318 had baseline serum OCPs and serum biomarkers measured at ages 10-13 years. Multivariable generalized estimating equation and mediation regression models were used to examine associations and direct and indirect (via body mass …

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. …

Preliminary Analysis Of In Utero Low-Level Arsenic Exposure And Fetal Growth Using Biometric Measurements Extracted From Fetal Ultrasound Reports, Matthew A. Davis, John Higgins, Zhigang Li, Diane Gilbert-Diamond, Emily R. Baker, Amar Das, Margaret R. Karagas

Dartmouth Scholarship

Background: Early life exposure to arsenic is associated with decreased birth weight in highly exposed populations but little is known about effects of low-level arsenic exposure on growth in utero.

Methods: Using a sample of 272 pregnancies from New Hampshire we obtained biometric measurements directly from fetal ultrasound reports commonly found in electronic medical records. We used information extraction methods to develop and validate an automated approach for mining biometric measurements from the text of clinical reports. As a preliminary analysis, we examined associations between in utero low-level arsenic exposure (as measured by maternal urinary arsenic concentration) and fetal growth …

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 …

Loss Of Prolyl Carboxypeptidase In Two-Kidney, One-Clip Goldblatt Hypertensive Mice, Nadja Grobe, Orly Leiva, Mariana Morris, Khalid M. Elased

Pharmacology and Toxicology Faculty Publications

It is well documented that angiotensin (Ang) II contributes to kidney disease progression. The protease prolyl carboxypeptidase (PRCP) is highly expressed in the kidney and may be renoprotective by degrading Ang II to Ang-(1-7). The aim of the study was to investigate whether renal PRCP protein expression and activity are altered in two-kidney, one-clip (2K1C) Goldblatt hypertensive mice. Left renal artery was constricted by using 0.12 mm silver clips. Blood pressure was measured using telemetry over the eleven weeks of study period and revealed an immediate increase in 2K1C animals during the first week of clip placement which was followed …

Hidden Formaldehyde In E-Cigarette Aerosols, R. Paul Jensen, Wentai Luo, James F. Pankow, Robert M. Strongin, David H. Peyton

Chemistry Faculty Publications and Presentations

This letter reports a chemical analysis of vapor from electronic cigarettes that shows high levels of formaldehyde, a known carcinogen. The authors project that the associated incremental lifetime risk of cancer could be higher than that from long-term smoking.

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. …

The Association Between Environmental Cadmium Exposure And All-Cause Mortality And Cardiovascular Disease In A Cohort Of Elderly Western Australian Women, Kane Deering

Theses : Honours

Introduction: Recent research suggests an association between environmental cadmium exposure and increased risk of, and death from, cardiovascular disease, the number one cause of mortality in Australia and worldwide. However, the research to date is neither comprehensive nor have there been any studies conducted on an Australian population. This study identified whether increasing concentrations of urinary cadmium in elderly West Australian women was associated with an increased odds of incidence of, and deaths from CVD, as well as all-cause mortality.

Method: Cadmium excretion was measured in urine samples collected at baseline (1998) from 1359 women from Perth who …

Investigating The Effect Of Arsenic On Chromium(Vi)-Induced Genotoxicity In Human Lung Fibroblasts, Jason Stewart Ms

All Student Scholarship

Hexavalent chromium (Cr(VI)) compounds are well-established human lung carcinogens. Arsenic (As) is a well documented human carcinogen with long term exposure to AS in drinking water being linked to lung, kidney and liver cancer, among others. Co-exposure studies are now becoming more common as humans are not exposed to just one toxicant at a time. This is the first study to investigate the effects of co-exposure with arsenic and soluble or particulate Cr(Vi) compounds in human lung fibroblasts.

Loss Of Multidrug Resistance-Associated Protein 1 (Mrp1/Abcc1) Potentiates Doxorubicin-Induced Cardiotoxicity In Mice, Wei Zhang

Theses and Dissertations--Toxicology and Cancer Biology

Doxorubicin (DOX) is a broad-spectrum and effective chemotherapeutic agent, but its use in oncologic practice is limited by dose-dependent cumulative cardiotoxicity. DOX-induced cardiotoxicity is in large part due to its ability to cause oxidative stress. Multidrug resistance associated protein 1 (MRP1/ABCC1) is a member of the ATP-binding cassette (ABC) transporter superfamily. By effluxing a wide variety of endogenous and exogenous substrates, Mrp1 plays important physiological roles in multiple tissues and also protects normal tissues against toxicants. However, the role of MRP1 in heart is largely unknown.

The role of Mrp1 in DOX-induced cardiotoxicity was investigated in Mrp1 null (Mrp1-/-) and …